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1 /*
2  * Copyright 2011 Christoph Bumiller
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice shall be included in
12  * all copies or substantial portions of the Software.
13  *
14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
17  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
18  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20  * OTHER DEALINGS IN THE SOFTWARE.
21  */
22 
23 #include "codegen/nv50_ir.h"
24 #include "codegen/nv50_ir_target.h"
25 #include "codegen/nv50_ir_build_util.h"
26 
27 extern "C" {
28 #include "util/u_math.h"
29 }
30 
31 namespace nv50_ir {
32 
33 bool
isNop() const34 Instruction::isNop() const
35 {
36    if (op == OP_PHI || op == OP_SPLIT || op == OP_MERGE || op == OP_CONSTRAINT)
37       return true;
38    if (terminator || join) // XXX: should terminator imply flow ?
39       return false;
40    if (op == OP_ATOM)
41       return false;
42    if (!fixed && op == OP_NOP)
43       return true;
44 
45    if (defExists(0) && def(0).rep()->reg.data.id < 0) {
46       for (int d = 1; defExists(d); ++d)
47          if (def(d).rep()->reg.data.id >= 0)
48             WARN("part of vector result is unused !\n");
49       return true;
50    }
51 
52    if (op == OP_MOV || op == OP_UNION) {
53       if (!getDef(0)->equals(getSrc(0)))
54          return false;
55       if (op == OP_UNION)
56          if (!def(0).rep()->equals(getSrc(1)))
57             return false;
58       return true;
59    }
60 
61    return false;
62 }
63 
isDead() const64 bool Instruction::isDead() const
65 {
66    if (op == OP_STORE ||
67        op == OP_EXPORT ||
68        op == OP_ATOM ||
69        op == OP_SUSTB || op == OP_SUSTP || op == OP_SUREDP || op == OP_SUREDB ||
70        op == OP_WRSV)
71       return false;
72 
73    for (int d = 0; defExists(d); ++d)
74       if (getDef(d)->refCount() || getDef(d)->reg.data.id >= 0)
75          return false;
76 
77    if (terminator || asFlow())
78       return false;
79    if (fixed)
80       return false;
81 
82    return true;
83 };
84 
85 // =============================================================================
86 
87 class CopyPropagation : public Pass
88 {
89 private:
90    virtual bool visit(BasicBlock *);
91 };
92 
93 // Propagate all MOVs forward to make subsequent optimization easier, except if
94 // the sources stem from a phi, in which case we don't want to mess up potential
95 // swaps $rX <-> $rY, i.e. do not create live range overlaps of phi src and def.
96 bool
visit(BasicBlock * bb)97 CopyPropagation::visit(BasicBlock *bb)
98 {
99    Instruction *mov, *si, *next;
100 
101    for (mov = bb->getEntry(); mov; mov = next) {
102       next = mov->next;
103       if (mov->op != OP_MOV || mov->fixed || !mov->getSrc(0)->asLValue())
104          continue;
105       if (mov->getPredicate())
106          continue;
107       if (mov->def(0).getFile() != mov->src(0).getFile())
108          continue;
109       si = mov->getSrc(0)->getInsn();
110       if (mov->getDef(0)->reg.data.id < 0 && si && si->op != OP_PHI) {
111          // propagate
112          mov->def(0).replace(mov->getSrc(0), false);
113          delete_Instruction(prog, mov);
114       }
115    }
116    return true;
117 }
118 
119 // =============================================================================
120 
121 class MergeSplits : public Pass
122 {
123 private:
124    virtual bool visit(BasicBlock *);
125 };
126 
127 // For SPLIT / MERGE pairs that operate on the same registers, replace the
128 // post-merge def with the SPLIT's source.
129 bool
visit(BasicBlock * bb)130 MergeSplits::visit(BasicBlock *bb)
131 {
132    Instruction *i, *next, *si;
133 
134    for (i = bb->getEntry(); i; i = next) {
135       next = i->next;
136       if (i->op != OP_MERGE || typeSizeof(i->dType) != 8)
137          continue;
138       si = i->getSrc(0)->getInsn();
139       if (si->op != OP_SPLIT || si != i->getSrc(1)->getInsn())
140          continue;
141       i->def(0).replace(si->getSrc(0), false);
142       delete_Instruction(prog, i);
143    }
144 
145    return true;
146 }
147 
148 // =============================================================================
149 
150 class LoadPropagation : public Pass
151 {
152 private:
153    virtual bool visit(BasicBlock *);
154 
155    void checkSwapSrc01(Instruction *);
156 
157    bool isCSpaceLoad(Instruction *);
158    bool isImmdLoad(Instruction *);
159    bool isAttribOrSharedLoad(Instruction *);
160 };
161 
162 bool
isCSpaceLoad(Instruction * ld)163 LoadPropagation::isCSpaceLoad(Instruction *ld)
164 {
165    return ld && ld->op == OP_LOAD && ld->src(0).getFile() == FILE_MEMORY_CONST;
166 }
167 
168 bool
isImmdLoad(Instruction * ld)169 LoadPropagation::isImmdLoad(Instruction *ld)
170 {
171    if (!ld || (ld->op != OP_MOV) ||
172        ((typeSizeof(ld->dType) != 4) && (typeSizeof(ld->dType) != 8)))
173       return false;
174 
175    // A 0 can be replaced with a register, so it doesn't count as an immediate.
176    ImmediateValue val;
177    return ld->src(0).getImmediate(val) && !val.isInteger(0);
178 }
179 
180 bool
isAttribOrSharedLoad(Instruction * ld)181 LoadPropagation::isAttribOrSharedLoad(Instruction *ld)
182 {
183    return ld &&
184       (ld->op == OP_VFETCH ||
185        (ld->op == OP_LOAD &&
186         (ld->src(0).getFile() == FILE_SHADER_INPUT ||
187          ld->src(0).getFile() == FILE_MEMORY_SHARED)));
188 }
189 
190 void
checkSwapSrc01(Instruction * insn)191 LoadPropagation::checkSwapSrc01(Instruction *insn)
192 {
193    const Target *targ = prog->getTarget();
194    if (!targ->getOpInfo(insn).commutative) {
195       if (insn->op != OP_SET && insn->op != OP_SLCT &&
196           insn->op != OP_SUB && insn->op != OP_XMAD)
197          return;
198       // XMAD is only commutative if both the CBCC and MRG flags are not set.
199       if (insn->op == OP_XMAD &&
200           (insn->subOp & NV50_IR_SUBOP_XMAD_CMODE_MASK) == NV50_IR_SUBOP_XMAD_CBCC)
201          return;
202       if (insn->op == OP_XMAD && (insn->subOp & NV50_IR_SUBOP_XMAD_MRG))
203          return;
204    }
205    if (insn->src(1).getFile() != FILE_GPR)
206       return;
207    // This is the special OP_SET used for alphatesting, we can't reverse its
208    // arguments as that will confuse the fixup code.
209    if (insn->op == OP_SET && insn->subOp)
210       return;
211 
212    Instruction *i0 = insn->getSrc(0)->getInsn();
213    Instruction *i1 = insn->getSrc(1)->getInsn();
214 
215    // Swap sources to inline the less frequently used source. That way,
216    // optimistically, it will eventually be able to remove the instruction.
217    int i0refs = insn->getSrc(0)->refCount();
218    int i1refs = insn->getSrc(1)->refCount();
219 
220    if ((isCSpaceLoad(i0) || isImmdLoad(i0)) && targ->insnCanLoad(insn, 1, i0)) {
221       if ((!isImmdLoad(i1) && !isCSpaceLoad(i1)) ||
222           !targ->insnCanLoad(insn, 1, i1) ||
223           i0refs < i1refs)
224          insn->swapSources(0, 1);
225       else
226          return;
227    } else
228    if (isAttribOrSharedLoad(i1)) {
229       if (!isAttribOrSharedLoad(i0))
230          insn->swapSources(0, 1);
231       else
232          return;
233    } else {
234       return;
235    }
236 
237    if (insn->op == OP_SET || insn->op == OP_SET_AND ||
238        insn->op == OP_SET_OR || insn->op == OP_SET_XOR)
239       insn->asCmp()->setCond = reverseCondCode(insn->asCmp()->setCond);
240    else
241    if (insn->op == OP_SLCT)
242       insn->asCmp()->setCond = inverseCondCode(insn->asCmp()->setCond);
243    else
244    if (insn->op == OP_SUB) {
245       insn->src(0).mod = insn->src(0).mod ^ Modifier(NV50_IR_MOD_NEG);
246       insn->src(1).mod = insn->src(1).mod ^ Modifier(NV50_IR_MOD_NEG);
247    } else
248    if (insn->op == OP_XMAD) {
249       // swap h1 flags
250       uint16_t h1 = (insn->subOp >> 1 & NV50_IR_SUBOP_XMAD_H1(0)) |
251                     (insn->subOp << 1 & NV50_IR_SUBOP_XMAD_H1(1));
252       insn->subOp = (insn->subOp & ~NV50_IR_SUBOP_XMAD_H1_MASK) | h1;
253    }
254 }
255 
256 bool
visit(BasicBlock * bb)257 LoadPropagation::visit(BasicBlock *bb)
258 {
259    const Target *targ = prog->getTarget();
260    Instruction *next;
261 
262    for (Instruction *i = bb->getEntry(); i; i = next) {
263       next = i->next;
264 
265       if (i->op == OP_CALL) // calls have args as sources, they must be in regs
266          continue;
267 
268       if (i->op == OP_PFETCH) // pfetch expects arg1 to be a reg
269          continue;
270 
271       if (i->srcExists(1))
272          checkSwapSrc01(i);
273 
274       for (int s = 0; i->srcExists(s); ++s) {
275          Instruction *ld = i->getSrc(s)->getInsn();
276 
277          if (!ld || ld->fixed || (ld->op != OP_LOAD && ld->op != OP_MOV))
278             continue;
279          if (!targ->insnCanLoad(i, s, ld))
280             continue;
281 
282          // propagate !
283          i->setSrc(s, ld->getSrc(0));
284          if (ld->src(0).isIndirect(0))
285             i->setIndirect(s, 0, ld->getIndirect(0, 0));
286 
287          if (ld->getDef(0)->refCount() == 0)
288             delete_Instruction(prog, ld);
289       }
290    }
291    return true;
292 }
293 
294 // =============================================================================
295 
296 class IndirectPropagation : public Pass
297 {
298 private:
299    virtual bool visit(BasicBlock *);
300 
301    BuildUtil bld;
302 };
303 
304 bool
visit(BasicBlock * bb)305 IndirectPropagation::visit(BasicBlock *bb)
306 {
307    const Target *targ = prog->getTarget();
308    Instruction *next;
309 
310    for (Instruction *i = bb->getEntry(); i; i = next) {
311       next = i->next;
312 
313       bld.setPosition(i, false);
314 
315       for (int s = 0; i->srcExists(s); ++s) {
316          Instruction *insn;
317          ImmediateValue imm;
318          if (!i->src(s).isIndirect(0))
319             continue;
320          insn = i->getIndirect(s, 0)->getInsn();
321          if (!insn)
322             continue;
323          if (insn->op == OP_ADD && !isFloatType(insn->dType)) {
324             if (insn->src(0).getFile() != targ->nativeFile(FILE_ADDRESS) ||
325                 !insn->src(1).getImmediate(imm) ||
326                 !targ->insnCanLoadOffset(i, s, imm.reg.data.s32))
327                continue;
328             i->setIndirect(s, 0, insn->getSrc(0));
329             i->setSrc(s, cloneShallow(func, i->getSrc(s)));
330             i->src(s).get()->reg.data.offset += imm.reg.data.u32;
331          } else if (insn->op == OP_SUB && !isFloatType(insn->dType)) {
332             if (insn->src(0).getFile() != targ->nativeFile(FILE_ADDRESS) ||
333                 !insn->src(1).getImmediate(imm) ||
334                 !targ->insnCanLoadOffset(i, s, -imm.reg.data.s32))
335                continue;
336             i->setIndirect(s, 0, insn->getSrc(0));
337             i->setSrc(s, cloneShallow(func, i->getSrc(s)));
338             i->src(s).get()->reg.data.offset -= imm.reg.data.u32;
339          } else if (insn->op == OP_MOV) {
340             if (!insn->src(0).getImmediate(imm) ||
341                 !targ->insnCanLoadOffset(i, s, imm.reg.data.s32))
342                continue;
343             i->setIndirect(s, 0, NULL);
344             i->setSrc(s, cloneShallow(func, i->getSrc(s)));
345             i->src(s).get()->reg.data.offset += imm.reg.data.u32;
346          } else if (insn->op == OP_SHLADD) {
347             if (!insn->src(2).getImmediate(imm) ||
348                 !targ->insnCanLoadOffset(i, s, imm.reg.data.s32))
349                continue;
350             i->setIndirect(s, 0, bld.mkOp2v(
351                OP_SHL, TYPE_U32, bld.getSSA(), insn->getSrc(0), insn->getSrc(1)));
352             i->setSrc(s, cloneShallow(func, i->getSrc(s)));
353             i->src(s).get()->reg.data.offset += imm.reg.data.u32;
354          }
355       }
356    }
357    return true;
358 }
359 
360 // =============================================================================
361 
362 // Evaluate constant expressions.
363 class ConstantFolding : public Pass
364 {
365 public:
366    bool foldAll(Program *);
367 
368 private:
369    virtual bool visit(BasicBlock *);
370 
371    void expr(Instruction *, ImmediateValue&, ImmediateValue&);
372    void expr(Instruction *, ImmediateValue&, ImmediateValue&, ImmediateValue&);
373    /* true if i was deleted */
374    bool opnd(Instruction *i, ImmediateValue&, int s);
375    void opnd3(Instruction *, ImmediateValue&);
376 
377    void unary(Instruction *, const ImmediateValue&);
378 
379    void tryCollapseChainedMULs(Instruction *, const int s, ImmediateValue&);
380 
381    CmpInstruction *findOriginForTestWithZero(Value *);
382 
383    bool createMul(DataType ty, Value *def, Value *a, int64_t b, Value *c);
384 
385    unsigned int foldCount;
386 
387    BuildUtil bld;
388 };
389 
390 // TODO: remember generated immediates and only revisit these
391 bool
foldAll(Program * prog)392 ConstantFolding::foldAll(Program *prog)
393 {
394    unsigned int iterCount = 0;
395    do {
396       foldCount = 0;
397       if (!run(prog))
398          return false;
399    } while (foldCount && ++iterCount < 2);
400    return true;
401 }
402 
403 bool
visit(BasicBlock * bb)404 ConstantFolding::visit(BasicBlock *bb)
405 {
406    Instruction *i, *next;
407 
408    for (i = bb->getEntry(); i; i = next) {
409       next = i->next;
410       if (i->op == OP_MOV || i->op == OP_CALL)
411          continue;
412 
413       ImmediateValue src0, src1, src2;
414 
415       if (i->srcExists(2) &&
416           i->src(0).getImmediate(src0) &&
417           i->src(1).getImmediate(src1) &&
418           i->src(2).getImmediate(src2)) {
419          expr(i, src0, src1, src2);
420       } else
421       if (i->srcExists(1) &&
422           i->src(0).getImmediate(src0) && i->src(1).getImmediate(src1)) {
423          expr(i, src0, src1);
424       } else
425       if (i->srcExists(0) && i->src(0).getImmediate(src0)) {
426          if (opnd(i, src0, 0))
427             continue;
428       } else
429       if (i->srcExists(1) && i->src(1).getImmediate(src1)) {
430          if (opnd(i, src1, 1))
431             continue;
432       }
433       if (i->srcExists(2) && i->src(2).getImmediate(src2))
434          opnd3(i, src2);
435    }
436    return true;
437 }
438 
439 CmpInstruction *
findOriginForTestWithZero(Value * value)440 ConstantFolding::findOriginForTestWithZero(Value *value)
441 {
442    if (!value)
443       return NULL;
444    Instruction *insn = value->getInsn();
445    if (!insn)
446       return NULL;
447 
448    if (insn->asCmp() && insn->op != OP_SLCT)
449       return insn->asCmp();
450 
451    /* Sometimes mov's will sneak in as a result of other folding. This gets
452     * cleaned up later.
453     */
454    if (insn->op == OP_MOV)
455       return findOriginForTestWithZero(insn->getSrc(0));
456 
457    /* Deal with AND 1.0 here since nv50 can't fold into boolean float */
458    if (insn->op == OP_AND) {
459       int s = 0;
460       ImmediateValue imm;
461       if (!insn->src(s).getImmediate(imm)) {
462          s = 1;
463          if (!insn->src(s).getImmediate(imm))
464             return NULL;
465       }
466       if (imm.reg.data.f32 != 1.0f)
467          return NULL;
468       /* TODO: Come up with a way to handle the condition being inverted */
469       if (insn->src(!s).mod != Modifier(0))
470          return NULL;
471       return findOriginForTestWithZero(insn->getSrc(!s));
472    }
473 
474    return NULL;
475 }
476 
477 void
applyTo(ImmediateValue & imm) const478 Modifier::applyTo(ImmediateValue& imm) const
479 {
480    if (!bits) // avoid failure if imm.reg.type is unhandled (e.g. b128)
481       return;
482    switch (imm.reg.type) {
483    case TYPE_F32:
484       if (bits & NV50_IR_MOD_ABS)
485          imm.reg.data.f32 = fabsf(imm.reg.data.f32);
486       if (bits & NV50_IR_MOD_NEG)
487          imm.reg.data.f32 = -imm.reg.data.f32;
488       if (bits & NV50_IR_MOD_SAT) {
489          if (imm.reg.data.f32 < 0.0f)
490             imm.reg.data.f32 = 0.0f;
491          else
492          if (imm.reg.data.f32 > 1.0f)
493             imm.reg.data.f32 = 1.0f;
494       }
495       assert(!(bits & NV50_IR_MOD_NOT));
496       break;
497 
498    case TYPE_S8: // NOTE: will be extended
499    case TYPE_S16:
500    case TYPE_S32:
501    case TYPE_U8: // NOTE: treated as signed
502    case TYPE_U16:
503    case TYPE_U32:
504       if (bits & NV50_IR_MOD_ABS)
505          imm.reg.data.s32 = (imm.reg.data.s32 >= 0) ?
506             imm.reg.data.s32 : -imm.reg.data.s32;
507       if (bits & NV50_IR_MOD_NEG)
508          imm.reg.data.s32 = -imm.reg.data.s32;
509       if (bits & NV50_IR_MOD_NOT)
510          imm.reg.data.s32 = ~imm.reg.data.s32;
511       break;
512 
513    case TYPE_F64:
514       if (bits & NV50_IR_MOD_ABS)
515          imm.reg.data.f64 = fabs(imm.reg.data.f64);
516       if (bits & NV50_IR_MOD_NEG)
517          imm.reg.data.f64 = -imm.reg.data.f64;
518       if (bits & NV50_IR_MOD_SAT) {
519          if (imm.reg.data.f64 < 0.0)
520             imm.reg.data.f64 = 0.0;
521          else
522          if (imm.reg.data.f64 > 1.0)
523             imm.reg.data.f64 = 1.0;
524       }
525       assert(!(bits & NV50_IR_MOD_NOT));
526       break;
527 
528    default:
529       assert(!"invalid/unhandled type");
530       imm.reg.data.u64 = 0;
531       break;
532    }
533 }
534 
535 operation
getOp() const536 Modifier::getOp() const
537 {
538    switch (bits) {
539    case NV50_IR_MOD_ABS: return OP_ABS;
540    case NV50_IR_MOD_NEG: return OP_NEG;
541    case NV50_IR_MOD_SAT: return OP_SAT;
542    case NV50_IR_MOD_NOT: return OP_NOT;
543    case 0:
544       return OP_MOV;
545    default:
546       return OP_CVT;
547    }
548 }
549 
550 void
expr(Instruction * i,ImmediateValue & imm0,ImmediateValue & imm1)551 ConstantFolding::expr(Instruction *i,
552                       ImmediateValue &imm0, ImmediateValue &imm1)
553 {
554    struct Storage *const a = &imm0.reg, *const b = &imm1.reg;
555    struct Storage res;
556    DataType type = i->dType;
557 
558    memset(&res.data, 0, sizeof(res.data));
559 
560    switch (i->op) {
561    case OP_SGXT: {
562       int bits = b->data.u32;
563       if (bits) {
564          uint32_t data = a->data.u32 & (0xffffffff >> (32 - bits));
565          if (bits < 32 && (data & (1 << (bits - 1))))
566             data = data - (1 << bits);
567          res.data.u32 = data;
568       }
569       break;
570    }
571    case OP_BMSK:
572       res.data.u32 = ((1 << b->data.u32) - 1) << a->data.u32;
573       break;
574    case OP_MAD:
575    case OP_FMA:
576    case OP_MUL:
577       if (i->dnz && i->dType == TYPE_F32) {
578          if (!isfinite(a->data.f32))
579             a->data.f32 = 0.0f;
580          if (!isfinite(b->data.f32))
581             b->data.f32 = 0.0f;
582       }
583       switch (i->dType) {
584       case TYPE_F32:
585          res.data.f32 = a->data.f32 * b->data.f32 * exp2f(i->postFactor);
586          break;
587       case TYPE_F64: res.data.f64 = a->data.f64 * b->data.f64; break;
588       case TYPE_S32:
589          if (i->subOp == NV50_IR_SUBOP_MUL_HIGH) {
590             res.data.s32 = ((int64_t)a->data.s32 * b->data.s32) >> 32;
591             break;
592          }
593          /* fallthrough */
594       case TYPE_U32:
595          if (i->subOp == NV50_IR_SUBOP_MUL_HIGH) {
596             res.data.u32 = ((uint64_t)a->data.u32 * b->data.u32) >> 32;
597             break;
598          }
599          res.data.u32 = a->data.u32 * b->data.u32; break;
600       default:
601          return;
602       }
603       break;
604    case OP_DIV:
605       if (b->data.u32 == 0)
606          break;
607       switch (i->dType) {
608       case TYPE_F32: res.data.f32 = a->data.f32 / b->data.f32; break;
609       case TYPE_F64: res.data.f64 = a->data.f64 / b->data.f64; break;
610       case TYPE_S32: res.data.s32 = a->data.s32 / b->data.s32; break;
611       case TYPE_U32: res.data.u32 = a->data.u32 / b->data.u32; break;
612       default:
613          return;
614       }
615       break;
616    case OP_ADD:
617       switch (i->dType) {
618       case TYPE_F32: res.data.f32 = a->data.f32 + b->data.f32; break;
619       case TYPE_F64: res.data.f64 = a->data.f64 + b->data.f64; break;
620       case TYPE_S32:
621       case TYPE_U32: res.data.u32 = a->data.u32 + b->data.u32; break;
622       default:
623          return;
624       }
625       break;
626    case OP_SUB:
627       switch (i->dType) {
628       case TYPE_F32: res.data.f32 = a->data.f32 - b->data.f32; break;
629       case TYPE_F64: res.data.f64 = a->data.f64 - b->data.f64; break;
630       case TYPE_S32:
631       case TYPE_U32: res.data.u32 = a->data.u32 - b->data.u32; break;
632       default:
633          return;
634       }
635       break;
636    case OP_POW:
637       switch (i->dType) {
638       case TYPE_F32: res.data.f32 = pow(a->data.f32, b->data.f32); break;
639       case TYPE_F64: res.data.f64 = pow(a->data.f64, b->data.f64); break;
640       default:
641          return;
642       }
643       break;
644    case OP_MAX:
645       switch (i->dType) {
646       case TYPE_F32: res.data.f32 = MAX2(a->data.f32, b->data.f32); break;
647       case TYPE_F64: res.data.f64 = MAX2(a->data.f64, b->data.f64); break;
648       case TYPE_S32: res.data.s32 = MAX2(a->data.s32, b->data.s32); break;
649       case TYPE_U32: res.data.u32 = MAX2(a->data.u32, b->data.u32); break;
650       default:
651          return;
652       }
653       break;
654    case OP_MIN:
655       switch (i->dType) {
656       case TYPE_F32: res.data.f32 = MIN2(a->data.f32, b->data.f32); break;
657       case TYPE_F64: res.data.f64 = MIN2(a->data.f64, b->data.f64); break;
658       case TYPE_S32: res.data.s32 = MIN2(a->data.s32, b->data.s32); break;
659       case TYPE_U32: res.data.u32 = MIN2(a->data.u32, b->data.u32); break;
660       default:
661          return;
662       }
663       break;
664    case OP_AND:
665       res.data.u64 = a->data.u64 & b->data.u64;
666       break;
667    case OP_OR:
668       res.data.u64 = a->data.u64 | b->data.u64;
669       break;
670    case OP_XOR:
671       res.data.u64 = a->data.u64 ^ b->data.u64;
672       break;
673    case OP_SHL:
674       res.data.u32 = a->data.u32 << b->data.u32;
675       break;
676    case OP_SHR:
677       switch (i->dType) {
678       case TYPE_S32: res.data.s32 = a->data.s32 >> b->data.u32; break;
679       case TYPE_U32: res.data.u32 = a->data.u32 >> b->data.u32; break;
680       default:
681          return;
682       }
683       break;
684    case OP_SLCT:
685       if (a->data.u32 != b->data.u32)
686          return;
687       res.data.u32 = a->data.u32;
688       break;
689    case OP_EXTBF: {
690       int offset = b->data.u32 & 0xff;
691       int width = (b->data.u32 >> 8) & 0xff;
692       int rshift = offset;
693       int lshift = 0;
694       if (width == 0) {
695          res.data.u32 = 0;
696          break;
697       }
698       if (width + offset < 32) {
699          rshift = 32 - width;
700          lshift = 32 - width - offset;
701       }
702       if (i->subOp == NV50_IR_SUBOP_EXTBF_REV)
703          res.data.u32 = util_bitreverse(a->data.u32);
704       else
705          res.data.u32 = a->data.u32;
706       switch (i->dType) {
707       case TYPE_S32: res.data.s32 = (res.data.s32 << lshift) >> rshift; break;
708       case TYPE_U32: res.data.u32 = (res.data.u32 << lshift) >> rshift; break;
709       default:
710          return;
711       }
712       break;
713    }
714    case OP_POPCNT:
715       res.data.u32 = util_bitcount(a->data.u32 & b->data.u32);
716       break;
717    case OP_PFETCH:
718       // The two arguments to pfetch are logically added together. Normally
719       // the second argument will not be constant, but that can happen.
720       res.data.u32 = a->data.u32 + b->data.u32;
721       type = TYPE_U32;
722       break;
723    case OP_MERGE:
724       switch (i->dType) {
725       case TYPE_U64:
726       case TYPE_S64:
727       case TYPE_F64:
728          res.data.u64 = (((uint64_t)b->data.u32) << 32) | a->data.u32;
729          break;
730       default:
731          return;
732       }
733       break;
734    default:
735       return;
736    }
737    ++foldCount;
738 
739    i->src(0).mod = Modifier(0);
740    i->src(1).mod = Modifier(0);
741    i->postFactor = 0;
742 
743    i->setSrc(0, new_ImmediateValue(i->bb->getProgram(), res.data.u32));
744    i->setSrc(1, NULL);
745 
746    i->getSrc(0)->reg.data = res.data;
747    i->getSrc(0)->reg.type = type;
748    i->getSrc(0)->reg.size = typeSizeof(type);
749 
750    switch (i->op) {
751    case OP_MAD:
752    case OP_FMA: {
753       ImmediateValue src0, src1 = *i->getSrc(0)->asImm();
754 
755       // Move the immediate into position 1, where we know it might be
756       // emittable. However it might not be anyways, as there may be other
757       // restrictions, so move it into a separate LValue.
758       bld.setPosition(i, false);
759       i->op = OP_ADD;
760       i->dnz = 0;
761       i->setSrc(1, bld.mkMov(bld.getSSA(type), i->getSrc(0), type)->getDef(0));
762       i->setSrc(0, i->getSrc(2));
763       i->src(0).mod = i->src(2).mod;
764       i->setSrc(2, NULL);
765 
766       if (i->src(0).getImmediate(src0))
767          expr(i, src0, src1);
768       else
769          opnd(i, src1, 1);
770       break;
771    }
772    case OP_PFETCH:
773       // Leave PFETCH alone... we just folded its 2 args into 1.
774       break;
775    default:
776       i->op = i->saturate ? OP_SAT : OP_MOV;
777       if (i->saturate)
778          unary(i, *i->getSrc(0)->asImm());
779       break;
780    }
781    i->subOp = 0;
782 }
783 
784 void
expr(Instruction * i,ImmediateValue & imm0,ImmediateValue & imm1,ImmediateValue & imm2)785 ConstantFolding::expr(Instruction *i,
786                       ImmediateValue &imm0,
787                       ImmediateValue &imm1,
788                       ImmediateValue &imm2)
789 {
790    struct Storage *const a = &imm0.reg, *const b = &imm1.reg, *const c = &imm2.reg;
791    struct Storage res;
792 
793    memset(&res.data, 0, sizeof(res.data));
794 
795    switch (i->op) {
796    case OP_LOP3_LUT:
797       for (int n = 0; n < 32; n++) {
798          uint8_t lut = ((a->data.u32 >> n) & 1) << 2 |
799                        ((b->data.u32 >> n) & 1) << 1 |
800                        ((c->data.u32 >> n) & 1);
801          res.data.u32 |= !!(i->subOp & (1 << lut)) << n;
802       }
803       break;
804    case OP_PERMT:
805       if (!i->subOp) {
806          uint64_t input = (uint64_t)c->data.u32 << 32 | a->data.u32;
807          uint16_t permt = b->data.u32;
808          for (int n = 0 ; n < 4; n++, permt >>= 4)
809             res.data.u32 |= ((input >> ((permt & 0xf) * 8)) & 0xff) << n * 8;
810       } else
811          return;
812       break;
813    case OP_INSBF: {
814       int offset = b->data.u32 & 0xff;
815       int width = (b->data.u32 >> 8) & 0xff;
816       unsigned bitmask = ((1 << width) - 1) << offset;
817       res.data.u32 = ((a->data.u32 << offset) & bitmask) | (c->data.u32 & ~bitmask);
818       break;
819    }
820    case OP_MAD:
821    case OP_FMA: {
822       switch (i->dType) {
823       case TYPE_F32:
824          res.data.f32 = a->data.f32 * b->data.f32 * exp2f(i->postFactor) +
825             c->data.f32;
826          break;
827       case TYPE_F64:
828          res.data.f64 = a->data.f64 * b->data.f64 + c->data.f64;
829          break;
830       case TYPE_S32:
831          if (i->subOp == NV50_IR_SUBOP_MUL_HIGH) {
832             res.data.s32 = ((int64_t)a->data.s32 * b->data.s32 >> 32) + c->data.s32;
833             break;
834          }
835          /* fallthrough */
836       case TYPE_U32:
837          if (i->subOp == NV50_IR_SUBOP_MUL_HIGH) {
838             res.data.u32 = ((uint64_t)a->data.u32 * b->data.u32 >> 32) + c->data.u32;
839             break;
840          }
841          res.data.u32 = a->data.u32 * b->data.u32 + c->data.u32;
842          break;
843       default:
844          return;
845       }
846       break;
847    }
848    case OP_SHLADD:
849       res.data.u32 = (a->data.u32 << b->data.u32) + c->data.u32;
850       break;
851    default:
852       return;
853    }
854 
855    ++foldCount;
856    i->src(0).mod = Modifier(0);
857    i->src(1).mod = Modifier(0);
858    i->src(2).mod = Modifier(0);
859 
860    i->setSrc(0, new_ImmediateValue(i->bb->getProgram(), res.data.u32));
861    i->setSrc(1, NULL);
862    i->setSrc(2, NULL);
863 
864    i->getSrc(0)->reg.data = res.data;
865    i->getSrc(0)->reg.type = i->dType;
866    i->getSrc(0)->reg.size = typeSizeof(i->dType);
867 
868    i->op = OP_MOV;
869 }
870 
871 void
unary(Instruction * i,const ImmediateValue & imm)872 ConstantFolding::unary(Instruction *i, const ImmediateValue &imm)
873 {
874    Storage res;
875 
876    if (i->dType != TYPE_F32)
877       return;
878    switch (i->op) {
879    case OP_NEG: res.data.f32 = -imm.reg.data.f32; break;
880    case OP_ABS: res.data.f32 = fabsf(imm.reg.data.f32); break;
881    case OP_SAT: res.data.f32 = SATURATE(imm.reg.data.f32); break;
882    case OP_RCP: res.data.f32 = 1.0f / imm.reg.data.f32; break;
883    case OP_RSQ: res.data.f32 = 1.0f / sqrtf(imm.reg.data.f32); break;
884    case OP_LG2: res.data.f32 = log2f(imm.reg.data.f32); break;
885    case OP_EX2: res.data.f32 = exp2f(imm.reg.data.f32); break;
886    case OP_SIN: res.data.f32 = sinf(imm.reg.data.f32); break;
887    case OP_COS: res.data.f32 = cosf(imm.reg.data.f32); break;
888    case OP_SQRT: res.data.f32 = sqrtf(imm.reg.data.f32); break;
889    case OP_PRESIN:
890    case OP_PREEX2:
891       // these should be handled in subsequent OP_SIN/COS/EX2
892       res.data.f32 = imm.reg.data.f32;
893       break;
894    default:
895       return;
896    }
897    i->op = OP_MOV;
898    i->setSrc(0, new_ImmediateValue(i->bb->getProgram(), res.data.f32));
899    i->src(0).mod = Modifier(0);
900 }
901 
902 void
tryCollapseChainedMULs(Instruction * mul2,const int s,ImmediateValue & imm2)903 ConstantFolding::tryCollapseChainedMULs(Instruction *mul2,
904                                         const int s, ImmediateValue& imm2)
905 {
906    const int t = s ? 0 : 1;
907    Instruction *insn;
908    Instruction *mul1 = NULL; // mul1 before mul2
909    int e = 0;
910    float f = imm2.reg.data.f32 * exp2f(mul2->postFactor);
911    ImmediateValue imm1;
912 
913    assert(mul2->op == OP_MUL && mul2->dType == TYPE_F32);
914 
915    if (mul2->getSrc(t)->refCount() == 1) {
916       insn = mul2->getSrc(t)->getInsn();
917       if (!mul2->src(t).mod && insn->op == OP_MUL && insn->dType == TYPE_F32)
918          mul1 = insn;
919       if (mul1 && !mul1->saturate) {
920          int s1;
921 
922          if (mul1->src(s1 = 0).getImmediate(imm1) ||
923              mul1->src(s1 = 1).getImmediate(imm1)) {
924             bld.setPosition(mul1, false);
925             // a = mul r, imm1
926             // d = mul a, imm2 -> d = mul r, (imm1 * imm2)
927             mul1->setSrc(s1, bld.loadImm(NULL, f * imm1.reg.data.f32));
928             mul1->src(s1).mod = Modifier(0);
929             mul2->def(0).replace(mul1->getDef(0), false);
930             mul1->saturate = mul2->saturate;
931          } else
932          if (prog->getTarget()->isPostMultiplySupported(OP_MUL, f, e)) {
933             // c = mul a, b
934             // d = mul c, imm   -> d = mul_x_imm a, b
935             mul1->postFactor = e;
936             mul2->def(0).replace(mul1->getDef(0), false);
937             if (f < 0)
938                mul1->src(0).mod *= Modifier(NV50_IR_MOD_NEG);
939             mul1->saturate = mul2->saturate;
940          }
941          return;
942       }
943    }
944    if (mul2->getDef(0)->refCount() == 1 && !mul2->saturate) {
945       // b = mul a, imm
946       // d = mul b, c   -> d = mul_x_imm a, c
947       int s2, t2;
948       insn = (*mul2->getDef(0)->uses.begin())->getInsn();
949       if (!insn)
950          return;
951       mul1 = mul2;
952       mul2 = NULL;
953       s2 = insn->getSrc(0) == mul1->getDef(0) ? 0 : 1;
954       t2 = s2 ? 0 : 1;
955       if (insn->op == OP_MUL && insn->dType == TYPE_F32)
956          if (!insn->src(s2).mod && !insn->src(t2).getImmediate(imm1))
957             mul2 = insn;
958       if (mul2 && prog->getTarget()->isPostMultiplySupported(OP_MUL, f, e)) {
959          mul2->postFactor = e;
960          mul2->setSrc(s2, mul1->src(t));
961          if (f < 0)
962             mul2->src(s2).mod *= Modifier(NV50_IR_MOD_NEG);
963       }
964    }
965 }
966 
967 void
opnd3(Instruction * i,ImmediateValue & imm2)968 ConstantFolding::opnd3(Instruction *i, ImmediateValue &imm2)
969 {
970    switch (i->op) {
971    case OP_MAD:
972    case OP_FMA:
973       if (imm2.isInteger(0)) {
974          i->op = OP_MUL;
975          i->setSrc(2, NULL);
976          foldCount++;
977          return;
978       }
979       break;
980    case OP_SHLADD:
981       if (imm2.isInteger(0)) {
982          i->op = OP_SHL;
983          i->setSrc(2, NULL);
984          foldCount++;
985          return;
986       }
987       break;
988    default:
989       return;
990    }
991 }
992 
993 bool
createMul(DataType ty,Value * def,Value * a,int64_t b,Value * c)994 ConstantFolding::createMul(DataType ty, Value *def, Value *a, int64_t b, Value *c)
995 {
996    const Target *target = prog->getTarget();
997    int64_t absB = llabs(b);
998 
999    //a * (2^shl) -> a << shl
1000    if (b >= 0 && util_is_power_of_two_or_zero64(b)) {
1001       int shl = util_logbase2_64(b);
1002 
1003       Value *res = c ? bld.getSSA(typeSizeof(ty)) : def;
1004       bld.mkOp2(OP_SHL, ty, res, a, bld.mkImm(shl));
1005       if (c)
1006          bld.mkOp2(OP_ADD, ty, def, res, c);
1007 
1008       return true;
1009    }
1010 
1011    //a * (2^shl + 1) -> a << shl + a
1012    //a * -(2^shl + 1) -> -a << shl + a
1013    //a * (2^shl - 1) -> a << shl - a
1014    //a * -(2^shl - 1) -> -a << shl - a
1015    if (typeSizeof(ty) == 4 &&
1016        (util_is_power_of_two_or_zero64(absB - 1) ||
1017         util_is_power_of_two_or_zero64(absB + 1)) &&
1018        target->isOpSupported(OP_SHLADD, TYPE_U32)) {
1019       bool subA = util_is_power_of_two_or_zero64(absB + 1);
1020       int shl = subA ? util_logbase2_64(absB + 1) : util_logbase2_64(absB - 1);
1021 
1022       Value *res = c ? bld.getSSA() : def;
1023       Instruction *insn = bld.mkOp3(OP_SHLADD, TYPE_U32, res, a, bld.mkImm(shl), a);
1024       if (b < 0)
1025          insn->src(0).mod = Modifier(NV50_IR_MOD_NEG);
1026       if (subA)
1027          insn->src(2).mod = Modifier(NV50_IR_MOD_NEG);
1028 
1029       if (c)
1030          bld.mkOp2(OP_ADD, TYPE_U32, def, res, c);
1031 
1032       return true;
1033    }
1034 
1035    if (typeSizeof(ty) == 4 && b >= 0 && b <= 0xffff &&
1036        target->isOpSupported(OP_XMAD, TYPE_U32)) {
1037       Value *tmp = bld.mkOp3v(OP_XMAD, TYPE_U32, bld.getSSA(),
1038                               a, bld.mkImm((uint32_t)b), c ? c : bld.mkImm(0));
1039       bld.mkOp3(OP_XMAD, TYPE_U32, def, a, bld.mkImm((uint32_t)b), tmp)->subOp =
1040          NV50_IR_SUBOP_XMAD_PSL | NV50_IR_SUBOP_XMAD_H1(0);
1041 
1042       return true;
1043    }
1044 
1045    return false;
1046 }
1047 
1048 bool
opnd(Instruction * i,ImmediateValue & imm0,int s)1049 ConstantFolding::opnd(Instruction *i, ImmediateValue &imm0, int s)
1050 {
1051    const int t = !s;
1052    const operation op = i->op;
1053    Instruction *newi = i;
1054    bool deleted = false;
1055 
1056    switch (i->op) {
1057    case OP_SPLIT: {
1058       bld.setPosition(i, false);
1059 
1060       uint8_t size = i->getDef(0)->reg.size;
1061       uint8_t bitsize = size * 8;
1062       uint32_t mask = (1ULL << bitsize) - 1;
1063       assert(bitsize <= 32);
1064 
1065       uint64_t val = imm0.reg.data.u64;
1066       for (int8_t d = 0; i->defExists(d); ++d) {
1067          Value *def = i->getDef(d);
1068          assert(def->reg.size == size);
1069 
1070          newi = bld.mkMov(def, bld.mkImm((uint32_t)(val & mask)), TYPE_U32);
1071          val >>= bitsize;
1072       }
1073       delete_Instruction(prog, i);
1074       deleted = true;
1075       break;
1076    }
1077    case OP_MUL:
1078       if (i->dType == TYPE_F32 && !i->precise)
1079          tryCollapseChainedMULs(i, s, imm0);
1080 
1081       if (i->subOp == NV50_IR_SUBOP_MUL_HIGH) {
1082          assert(!isFloatType(i->sType));
1083          if (imm0.isInteger(1) && i->dType == TYPE_S32) {
1084             bld.setPosition(i, false);
1085             // Need to set to the sign value, which is a compare.
1086             newi = bld.mkCmp(OP_SET, CC_LT, TYPE_S32, i->getDef(0),
1087                              TYPE_S32, i->getSrc(t), bld.mkImm(0));
1088             delete_Instruction(prog, i);
1089             deleted = true;
1090          } else if (imm0.isInteger(0) || imm0.isInteger(1)) {
1091             // The high bits can't be set in this case (either mul by 0 or
1092             // unsigned by 1)
1093             i->op = OP_MOV;
1094             i->subOp = 0;
1095             i->setSrc(0, new_ImmediateValue(prog, 0u));
1096             i->src(0).mod = Modifier(0);
1097             i->setSrc(1, NULL);
1098          } else if (!imm0.isNegative() && imm0.isPow2()) {
1099             // Translate into a shift
1100             imm0.applyLog2();
1101             i->op = OP_SHR;
1102             i->subOp = 0;
1103             imm0.reg.data.u32 = 32 - imm0.reg.data.u32;
1104             i->setSrc(0, i->getSrc(t));
1105             i->src(0).mod = i->src(t).mod;
1106             i->setSrc(1, new_ImmediateValue(prog, imm0.reg.data.u32));
1107             i->src(1).mod = 0;
1108          }
1109       } else
1110       if (imm0.isInteger(0)) {
1111          i->op = OP_MOV;
1112          i->setSrc(0, new_ImmediateValue(prog, 0u));
1113          i->src(0).mod = Modifier(0);
1114          i->postFactor = 0;
1115          i->setSrc(1, NULL);
1116       } else
1117       if (!i->postFactor && (imm0.isInteger(1) || imm0.isInteger(-1))) {
1118          if (imm0.isNegative())
1119             i->src(t).mod = i->src(t).mod ^ Modifier(NV50_IR_MOD_NEG);
1120          i->op = i->src(t).mod.getOp();
1121          if (s == 0) {
1122             i->setSrc(0, i->getSrc(1));
1123             i->src(0).mod = i->src(1).mod;
1124             i->src(1).mod = 0;
1125          }
1126          if (i->op != OP_CVT)
1127             i->src(0).mod = 0;
1128          i->setSrc(1, NULL);
1129       } else
1130       if (!i->postFactor && (imm0.isInteger(2) || imm0.isInteger(-2))) {
1131          if (imm0.isNegative())
1132             i->src(t).mod = i->src(t).mod ^ Modifier(NV50_IR_MOD_NEG);
1133          i->op = OP_ADD;
1134          i->dnz = 0;
1135          i->setSrc(s, i->getSrc(t));
1136          i->src(s).mod = i->src(t).mod;
1137       } else
1138       if (!isFloatType(i->dType) && !i->src(t).mod) {
1139          bld.setPosition(i, false);
1140          int64_t b = typeSizeof(i->dType) == 8 ? imm0.reg.data.s64 : imm0.reg.data.s32;
1141          if (createMul(i->dType, i->getDef(0), i->getSrc(t), b, NULL)) {
1142             delete_Instruction(prog, i);
1143             deleted = true;
1144          }
1145       } else
1146       if (i->postFactor && i->sType == TYPE_F32) {
1147          /* Can't emit a postfactor with an immediate, have to fold it in */
1148          i->setSrc(s, new_ImmediateValue(
1149                       prog, imm0.reg.data.f32 * exp2f(i->postFactor)));
1150          i->postFactor = 0;
1151       }
1152       break;
1153    case OP_FMA:
1154    case OP_MAD:
1155       if (imm0.isInteger(0)) {
1156          i->setSrc(0, i->getSrc(2));
1157          i->src(0).mod = i->src(2).mod;
1158          i->setSrc(1, NULL);
1159          i->setSrc(2, NULL);
1160          i->op = i->src(0).mod.getOp();
1161          if (i->op != OP_CVT)
1162             i->src(0).mod = 0;
1163       } else
1164       if (i->subOp != NV50_IR_SUBOP_MUL_HIGH &&
1165           (imm0.isInteger(1) || imm0.isInteger(-1))) {
1166          if (imm0.isNegative())
1167             i->src(t).mod = i->src(t).mod ^ Modifier(NV50_IR_MOD_NEG);
1168          if (s == 0) {
1169             i->setSrc(0, i->getSrc(1));
1170             i->src(0).mod = i->src(1).mod;
1171          }
1172          i->setSrc(1, i->getSrc(2));
1173          i->src(1).mod = i->src(2).mod;
1174          i->setSrc(2, NULL);
1175          i->dnz = 0;
1176          i->op = OP_ADD;
1177       } else
1178       if (!isFloatType(i->dType) && !i->subOp && !i->src(t).mod && !i->src(2).mod) {
1179          bld.setPosition(i, false);
1180          int64_t b = typeSizeof(i->dType) == 8 ? imm0.reg.data.s64 : imm0.reg.data.s32;
1181          if (createMul(i->dType, i->getDef(0), i->getSrc(t), b, i->getSrc(2))) {
1182             delete_Instruction(prog, i);
1183             deleted = true;
1184          }
1185       }
1186       break;
1187    case OP_SUB:
1188       if (imm0.isInteger(0) && s == 0 && typeSizeof(i->dType) == 8 &&
1189           !isFloatType(i->dType))
1190          break;
1191       /* fallthrough */
1192    case OP_ADD:
1193       if (i->usesFlags())
1194          break;
1195       if (imm0.isInteger(0)) {
1196          if (s == 0) {
1197             i->setSrc(0, i->getSrc(1));
1198             i->src(0).mod = i->src(1).mod;
1199             if (i->op == OP_SUB)
1200                i->src(0).mod = i->src(0).mod ^ Modifier(NV50_IR_MOD_NEG);
1201          }
1202          i->setSrc(1, NULL);
1203          i->op = i->src(0).mod.getOp();
1204          if (i->op != OP_CVT)
1205             i->src(0).mod = Modifier(0);
1206       }
1207       break;
1208 
1209    case OP_DIV:
1210       if (s != 1 || (i->dType != TYPE_S32 && i->dType != TYPE_U32))
1211          break;
1212       bld.setPosition(i, false);
1213       if (imm0.reg.data.u32 == 0) {
1214          break;
1215       } else
1216       if (imm0.reg.data.u32 == 1) {
1217          i->op = OP_MOV;
1218          i->setSrc(1, NULL);
1219       } else
1220       if (i->dType == TYPE_U32 && imm0.isPow2()) {
1221          i->op = OP_SHR;
1222          i->setSrc(1, bld.mkImm(util_logbase2(imm0.reg.data.u32)));
1223       } else
1224       if (i->dType == TYPE_U32) {
1225          Instruction *mul;
1226          Value *tA, *tB;
1227          const uint32_t d = imm0.reg.data.u32;
1228          uint32_t m;
1229          int r, s;
1230          uint32_t l = util_logbase2(d);
1231          if (((uint32_t)1 << l) < d)
1232             ++l;
1233          m = (((uint64_t)1 << 32) * (((uint64_t)1 << l) - d)) / d + 1;
1234          r = l ? 1 : 0;
1235          s = l ? (l - 1) : 0;
1236 
1237          tA = bld.getSSA();
1238          tB = bld.getSSA();
1239          mul = bld.mkOp2(OP_MUL, TYPE_U32, tA, i->getSrc(0),
1240                          bld.loadImm(NULL, m));
1241          mul->subOp = NV50_IR_SUBOP_MUL_HIGH;
1242          bld.mkOp2(OP_SUB, TYPE_U32, tB, i->getSrc(0), tA);
1243          tA = bld.getSSA();
1244          if (r)
1245             bld.mkOp2(OP_SHR, TYPE_U32, tA, tB, bld.mkImm(r));
1246          else
1247             tA = tB;
1248          tB = s ? bld.getSSA() : i->getDef(0);
1249          newi = bld.mkOp2(OP_ADD, TYPE_U32, tB, mul->getDef(0), tA);
1250          if (s)
1251             bld.mkOp2(OP_SHR, TYPE_U32, i->getDef(0), tB, bld.mkImm(s));
1252 
1253          delete_Instruction(prog, i);
1254          deleted = true;
1255       } else
1256       if (imm0.reg.data.s32 == -1) {
1257          i->op = OP_NEG;
1258          i->setSrc(1, NULL);
1259       } else {
1260          LValue *tA, *tB;
1261          LValue *tD;
1262          const int32_t d = imm0.reg.data.s32;
1263          int32_t m;
1264          int32_t l = util_logbase2(static_cast<unsigned>(abs(d)));
1265          if ((1 << l) < abs(d))
1266             ++l;
1267          if (!l)
1268             l = 1;
1269          m = ((uint64_t)1 << (32 + l - 1)) / abs(d) + 1 - ((uint64_t)1 << 32);
1270 
1271          tA = bld.getSSA();
1272          tB = bld.getSSA();
1273          bld.mkOp3(OP_MAD, TYPE_S32, tA, i->getSrc(0), bld.loadImm(NULL, m),
1274                    i->getSrc(0))->subOp = NV50_IR_SUBOP_MUL_HIGH;
1275          if (l > 1)
1276             bld.mkOp2(OP_SHR, TYPE_S32, tB, tA, bld.mkImm(l - 1));
1277          else
1278             tB = tA;
1279          tA = bld.getSSA();
1280          bld.mkCmp(OP_SET, CC_LT, TYPE_S32, tA, TYPE_S32, i->getSrc(0), bld.mkImm(0));
1281          tD = (d < 0) ? bld.getSSA() : i->getDef(0)->asLValue();
1282          newi = bld.mkOp2(OP_SUB, TYPE_U32, tD, tB, tA);
1283          if (d < 0)
1284             bld.mkOp1(OP_NEG, TYPE_S32, i->getDef(0), tB);
1285 
1286          delete_Instruction(prog, i);
1287          deleted = true;
1288       }
1289       break;
1290 
1291    case OP_MOD:
1292       if (s == 1 && imm0.isPow2()) {
1293          bld.setPosition(i, false);
1294          if (i->sType == TYPE_U32) {
1295             i->op = OP_AND;
1296             i->setSrc(1, bld.loadImm(NULL, imm0.reg.data.u32 - 1));
1297          } else if (i->sType == TYPE_S32) {
1298             // Do it on the absolute value of the input, and then restore the
1299             // sign. The only odd case is MIN_INT, but that should work out
1300             // as well, since MIN_INT mod any power of 2 is 0.
1301             //
1302             // Technically we don't have to do any of this since MOD is
1303             // undefined with negative arguments in GLSL, but this seems like
1304             // the nice thing to do.
1305             Value *abs = bld.mkOp1v(OP_ABS, TYPE_S32, bld.getSSA(), i->getSrc(0));
1306             Value *neg, *v1, *v2;
1307             bld.mkCmp(OP_SET, CC_LT, TYPE_S32,
1308                       (neg = bld.getSSA(1, prog->getTarget()->nativeFile(FILE_PREDICATE))),
1309                       TYPE_S32, i->getSrc(0), bld.loadImm(NULL, 0));
1310             Value *mod = bld.mkOp2v(OP_AND, TYPE_U32, bld.getSSA(), abs,
1311                                     bld.loadImm(NULL, imm0.reg.data.u32 - 1));
1312             bld.mkOp1(OP_NEG, TYPE_S32, (v1 = bld.getSSA()), mod)
1313                ->setPredicate(CC_P, neg);
1314             bld.mkOp1(OP_MOV, TYPE_S32, (v2 = bld.getSSA()), mod)
1315                ->setPredicate(CC_NOT_P, neg);
1316             newi = bld.mkOp2(OP_UNION, TYPE_S32, i->getDef(0), v1, v2);
1317 
1318             delete_Instruction(prog, i);
1319             deleted = true;
1320          }
1321       } else if (s == 1) {
1322          // In this case, we still want the optimized lowering that we get
1323          // from having division by an immediate.
1324          //
1325          // a % b == a - (a/b) * b
1326          bld.setPosition(i, false);
1327          Value *div = bld.mkOp2v(OP_DIV, i->sType, bld.getSSA(),
1328                                  i->getSrc(0), i->getSrc(1));
1329          newi = bld.mkOp2(OP_ADD, i->sType, i->getDef(0), i->getSrc(0),
1330                           bld.mkOp2v(OP_MUL, i->sType, bld.getSSA(), div, i->getSrc(1)));
1331          // TODO: Check that target supports this. In this case, we know that
1332          // all backends do.
1333          newi->src(1).mod = Modifier(NV50_IR_MOD_NEG);
1334 
1335          delete_Instruction(prog, i);
1336          deleted = true;
1337       }
1338       break;
1339 
1340    case OP_SET: // TODO: SET_AND,OR,XOR
1341    {
1342       /* This optimizes the case where the output of a set is being compared
1343        * to zero. Since the set can only produce 0/-1 (int) or 0/1 (float), we
1344        * can be a lot cleverer in our comparison.
1345        */
1346       CmpInstruction *si = findOriginForTestWithZero(i->getSrc(t));
1347       CondCode cc, ccZ;
1348       if (imm0.reg.data.u32 != 0 || !si)
1349          return false;
1350       cc = si->setCond;
1351       ccZ = (CondCode)((unsigned int)i->asCmp()->setCond & ~CC_U);
1352       // We do everything assuming var (cmp) 0, reverse the condition if 0 is
1353       // first.
1354       if (s == 0)
1355          ccZ = reverseCondCode(ccZ);
1356       // If there is a negative modifier, we need to undo that, by flipping
1357       // the comparison to zero.
1358       if (i->src(t).mod.neg())
1359          ccZ = reverseCondCode(ccZ);
1360       // If this is a signed comparison, we expect the input to be a regular
1361       // boolean, i.e. 0/-1. However the rest of the logic assumes that true
1362       // is positive, so just flip the sign.
1363       if (i->sType == TYPE_S32) {
1364          assert(!isFloatType(si->dType));
1365          ccZ = reverseCondCode(ccZ);
1366       }
1367       switch (ccZ) {
1368       case CC_LT: cc = CC_FL; break; // bool < 0 -- this is never true
1369       case CC_GE: cc = CC_TR; break; // bool >= 0 -- this is always true
1370       case CC_EQ: cc = inverseCondCode(cc); break; // bool == 0 -- !bool
1371       case CC_LE: cc = inverseCondCode(cc); break; // bool <= 0 -- !bool
1372       case CC_GT: break; // bool > 0 -- bool
1373       case CC_NE: break; // bool != 0 -- bool
1374       default:
1375          return false;
1376       }
1377 
1378       // Update the condition of this SET to be identical to the origin set,
1379       // but with the updated condition code. The original SET should get
1380       // DCE'd, ideally.
1381       i->op = si->op;
1382       i->asCmp()->setCond = cc;
1383       i->setSrc(0, si->src(0));
1384       i->setSrc(1, si->src(1));
1385       if (si->srcExists(2))
1386          i->setSrc(2, si->src(2));
1387       i->sType = si->sType;
1388    }
1389       break;
1390 
1391    case OP_AND:
1392    {
1393       Instruction *src = i->getSrc(t)->getInsn();
1394       ImmediateValue imm1;
1395       if (imm0.reg.data.u32 == 0) {
1396          i->op = OP_MOV;
1397          i->setSrc(0, new_ImmediateValue(prog, 0u));
1398          i->src(0).mod = Modifier(0);
1399          i->setSrc(1, NULL);
1400       } else if (imm0.reg.data.u32 == ~0U) {
1401          i->op = i->src(t).mod.getOp();
1402          if (t) {
1403             i->setSrc(0, i->getSrc(t));
1404             i->src(0).mod = i->src(t).mod;
1405          }
1406          i->setSrc(1, NULL);
1407       } else if (src->asCmp()) {
1408          CmpInstruction *cmp = src->asCmp();
1409          if (!cmp || cmp->op == OP_SLCT || cmp->getDef(0)->refCount() > 1)
1410             return false;
1411          if (!prog->getTarget()->isOpSupported(cmp->op, TYPE_F32))
1412             return false;
1413          if (imm0.reg.data.f32 != 1.0)
1414             return false;
1415          if (cmp->dType != TYPE_U32)
1416             return false;
1417 
1418          cmp->dType = TYPE_F32;
1419          if (i->src(t).mod != Modifier(0)) {
1420             assert(i->src(t).mod == Modifier(NV50_IR_MOD_NOT));
1421             i->src(t).mod = Modifier(0);
1422             cmp->setCond = inverseCondCode(cmp->setCond);
1423          }
1424          i->op = OP_MOV;
1425          i->setSrc(s, NULL);
1426          if (t) {
1427             i->setSrc(0, i->getSrc(t));
1428             i->setSrc(t, NULL);
1429          }
1430       } else if (prog->getTarget()->isOpSupported(OP_EXTBF, TYPE_U32) &&
1431                  src->op == OP_SHR &&
1432                  src->src(1).getImmediate(imm1) &&
1433                  i->src(t).mod == Modifier(0) &&
1434                  util_is_power_of_two_or_zero(imm0.reg.data.u32 + 1)) {
1435          // low byte = offset, high byte = width
1436          uint32_t ext = (util_last_bit(imm0.reg.data.u32) << 8) | imm1.reg.data.u32;
1437          i->op = OP_EXTBF;
1438          i->setSrc(0, src->getSrc(0));
1439          i->setSrc(1, new_ImmediateValue(prog, ext));
1440       } else if (src->op == OP_SHL &&
1441                  src->src(1).getImmediate(imm1) &&
1442                  i->src(t).mod == Modifier(0) &&
1443                  util_is_power_of_two_or_zero(~imm0.reg.data.u32 + 1) &&
1444                  util_last_bit(~imm0.reg.data.u32) <= imm1.reg.data.u32) {
1445          i->op = OP_MOV;
1446          i->setSrc(s, NULL);
1447          if (t) {
1448             i->setSrc(0, i->getSrc(t));
1449             i->setSrc(t, NULL);
1450          }
1451       }
1452    }
1453       break;
1454 
1455    case OP_SHL:
1456    {
1457       if (s != 1 || i->src(0).mod != Modifier(0))
1458          break;
1459       // try to concatenate shifts
1460       Instruction *si = i->getSrc(0)->getInsn();
1461       if (!si)
1462          break;
1463       ImmediateValue imm1;
1464       switch (si->op) {
1465       case OP_SHL:
1466          if (si->src(1).getImmediate(imm1)) {
1467             bld.setPosition(i, false);
1468             i->setSrc(0, si->getSrc(0));
1469             i->setSrc(1, bld.loadImm(NULL, imm0.reg.data.u32 + imm1.reg.data.u32));
1470          }
1471          break;
1472       case OP_SHR:
1473          if (si->src(1).getImmediate(imm1) && imm0.reg.data.u32 == imm1.reg.data.u32) {
1474             bld.setPosition(i, false);
1475             i->op = OP_AND;
1476             i->setSrc(0, si->getSrc(0));
1477             i->setSrc(1, bld.loadImm(NULL, ~((1 << imm0.reg.data.u32) - 1)));
1478          }
1479          break;
1480       case OP_MUL:
1481          int muls;
1482          if (isFloatType(si->dType))
1483             return false;
1484          if (si->src(1).getImmediate(imm1))
1485             muls = 1;
1486          else if (si->src(0).getImmediate(imm1))
1487             muls = 0;
1488          else
1489             return false;
1490 
1491          bld.setPosition(i, false);
1492          i->op = OP_MUL;
1493          i->setSrc(0, si->getSrc(!muls));
1494          i->setSrc(1, bld.loadImm(NULL, imm1.reg.data.u32 << imm0.reg.data.u32));
1495          break;
1496       case OP_SUB:
1497       case OP_ADD:
1498          int adds;
1499          if (isFloatType(si->dType))
1500             return false;
1501          if (si->op != OP_SUB && si->src(0).getImmediate(imm1))
1502             adds = 0;
1503          else if (si->src(1).getImmediate(imm1))
1504             adds = 1;
1505          else
1506             return false;
1507          if (si->src(!adds).mod != Modifier(0))
1508             return false;
1509          // SHL(ADD(x, y), z) = ADD(SHL(x, z), SHL(y, z))
1510 
1511          // This is more operations, but if one of x, y is an immediate, then
1512          // we can get a situation where (a) we can use ISCADD, or (b)
1513          // propagate the add bit into an indirect load.
1514          bld.setPosition(i, false);
1515          i->op = si->op;
1516          i->setSrc(adds, bld.loadImm(NULL, imm1.reg.data.u32 << imm0.reg.data.u32));
1517          i->setSrc(!adds, bld.mkOp2v(OP_SHL, i->dType,
1518                                      bld.getSSA(i->def(0).getSize(), i->def(0).getFile()),
1519                                      si->getSrc(!adds),
1520                                      bld.mkImm(imm0.reg.data.u32)));
1521          break;
1522       default:
1523          return false;
1524       }
1525    }
1526       break;
1527 
1528    case OP_ABS:
1529    case OP_NEG:
1530    case OP_SAT:
1531    case OP_LG2:
1532    case OP_RCP:
1533    case OP_SQRT:
1534    case OP_RSQ:
1535    case OP_PRESIN:
1536    case OP_SIN:
1537    case OP_COS:
1538    case OP_PREEX2:
1539    case OP_EX2:
1540       unary(i, imm0);
1541       break;
1542    case OP_BFIND: {
1543       int32_t res;
1544       switch (i->dType) {
1545       case TYPE_S32: res = util_last_bit_signed(imm0.reg.data.s32) - 1; break;
1546       case TYPE_U32: res = util_last_bit(imm0.reg.data.u32) - 1; break;
1547       default:
1548          return false;
1549       }
1550       if (i->subOp == NV50_IR_SUBOP_BFIND_SAMT && res >= 0)
1551          res = 31 - res;
1552       bld.setPosition(i, false); /* make sure bld is init'ed */
1553       i->setSrc(0, bld.mkImm(res));
1554       i->setSrc(1, NULL);
1555       i->op = OP_MOV;
1556       i->subOp = 0;
1557       break;
1558    }
1559    case OP_BREV: {
1560       uint32_t res = util_bitreverse(imm0.reg.data.u32);
1561       i->setSrc(0, new_ImmediateValue(i->bb->getProgram(), res));
1562       i->op = OP_MOV;
1563       break;
1564    }
1565    case OP_POPCNT: {
1566       // Only deal with 1-arg POPCNT here
1567       if (i->srcExists(1))
1568          break;
1569       uint32_t res = util_bitcount(imm0.reg.data.u32);
1570       i->setSrc(0, new_ImmediateValue(i->bb->getProgram(), res));
1571       i->setSrc(1, NULL);
1572       i->op = OP_MOV;
1573       break;
1574    }
1575    case OP_CVT: {
1576       Storage res;
1577 
1578       // TODO: handle 64-bit values properly
1579       if (typeSizeof(i->dType) == 8 || typeSizeof(i->sType) == 8)
1580          return false;
1581 
1582       // TODO: handle single byte/word extractions
1583       if (i->subOp)
1584          return false;
1585 
1586       bld.setPosition(i, true); /* make sure bld is init'ed */
1587 
1588 #define CASE(type, dst, fmin, fmax, imin, imax, umin, umax) \
1589    case type: \
1590       switch (i->sType) { \
1591       case TYPE_F64: \
1592          res.data.dst = util_iround(i->saturate ? \
1593                                     CLAMP(imm0.reg.data.f64, fmin, fmax) : \
1594                                     imm0.reg.data.f64); \
1595          break; \
1596       case TYPE_F32: \
1597          res.data.dst = util_iround(i->saturate ? \
1598                                     CLAMP(imm0.reg.data.f32, fmin, fmax) : \
1599                                     imm0.reg.data.f32); \
1600          break; \
1601       case TYPE_S32: \
1602          res.data.dst = i->saturate ? \
1603                         CLAMP(imm0.reg.data.s32, imin, imax) : \
1604                         imm0.reg.data.s32; \
1605          break; \
1606       case TYPE_U32: \
1607          res.data.dst = i->saturate ? \
1608                         CLAMP(imm0.reg.data.u32, umin, umax) : \
1609                         imm0.reg.data.u32; \
1610          break; \
1611       case TYPE_S16: \
1612          res.data.dst = i->saturate ? \
1613                         CLAMP(imm0.reg.data.s16, imin, imax) : \
1614                         imm0.reg.data.s16; \
1615          break; \
1616       case TYPE_U16: \
1617          res.data.dst = i->saturate ? \
1618                         CLAMP(imm0.reg.data.u16, umin, umax) : \
1619                         imm0.reg.data.u16; \
1620          break; \
1621       default: return false; \
1622       } \
1623       i->setSrc(0, bld.mkImm(res.data.dst)); \
1624       break
1625 
1626       switch(i->dType) {
1627       CASE(TYPE_U16, u16, 0, UINT16_MAX, 0, UINT16_MAX, 0, UINT16_MAX);
1628       CASE(TYPE_S16, s16, INT16_MIN, INT16_MAX, INT16_MIN, INT16_MAX, 0, INT16_MAX);
1629       CASE(TYPE_U32, u32, 0, UINT32_MAX, 0, INT32_MAX, 0, UINT32_MAX);
1630       CASE(TYPE_S32, s32, INT32_MIN, INT32_MAX, INT32_MIN, INT32_MAX, 0, INT32_MAX);
1631       case TYPE_F32:
1632          switch (i->sType) {
1633          case TYPE_F64:
1634             res.data.f32 = i->saturate ?
1635                SATURATE(imm0.reg.data.f64) :
1636                imm0.reg.data.f64;
1637             break;
1638          case TYPE_F32:
1639             res.data.f32 = i->saturate ?
1640                SATURATE(imm0.reg.data.f32) :
1641                imm0.reg.data.f32;
1642             break;
1643          case TYPE_U16: res.data.f32 = (float) imm0.reg.data.u16; break;
1644          case TYPE_U32: res.data.f32 = (float) imm0.reg.data.u32; break;
1645          case TYPE_S16: res.data.f32 = (float) imm0.reg.data.s16; break;
1646          case TYPE_S32: res.data.f32 = (float) imm0.reg.data.s32; break;
1647          default:
1648             return false;
1649          }
1650          i->setSrc(0, bld.mkImm(res.data.f32));
1651          break;
1652       case TYPE_F64:
1653          switch (i->sType) {
1654          case TYPE_F64:
1655             res.data.f64 = i->saturate ?
1656                SATURATE(imm0.reg.data.f64) :
1657                imm0.reg.data.f64;
1658             break;
1659          case TYPE_F32:
1660             res.data.f64 = i->saturate ?
1661                SATURATE(imm0.reg.data.f32) :
1662                imm0.reg.data.f32;
1663             break;
1664          case TYPE_U16: res.data.f64 = (double) imm0.reg.data.u16; break;
1665          case TYPE_U32: res.data.f64 = (double) imm0.reg.data.u32; break;
1666          case TYPE_S16: res.data.f64 = (double) imm0.reg.data.s16; break;
1667          case TYPE_S32: res.data.f64 = (double) imm0.reg.data.s32; break;
1668          default:
1669             return false;
1670          }
1671          i->setSrc(0, bld.mkImm(res.data.f64));
1672          break;
1673       default:
1674          return false;
1675       }
1676 #undef CASE
1677 
1678       i->setType(i->dType); /* Remove i->sType, which we don't need anymore */
1679       i->op = OP_MOV;
1680       i->saturate = 0;
1681       i->src(0).mod = Modifier(0); /* Clear the already applied modifier */
1682       break;
1683    }
1684    default:
1685       return false;
1686    }
1687 
1688    // This can get left behind some of the optimizations which simplify
1689    // saturatable values.
1690    if (newi->op == OP_MOV && newi->saturate) {
1691       ImmediateValue tmp;
1692       newi->saturate = 0;
1693       newi->op = OP_SAT;
1694       if (newi->src(0).getImmediate(tmp))
1695          unary(newi, tmp);
1696    }
1697 
1698    if (newi->op != op)
1699       foldCount++;
1700    return deleted;
1701 }
1702 
1703 // =============================================================================
1704 
1705 // Merge modifier operations (ABS, NEG, NOT) into ValueRefs where allowed.
1706 class ModifierFolding : public Pass
1707 {
1708 private:
1709    virtual bool visit(BasicBlock *);
1710 };
1711 
1712 bool
visit(BasicBlock * bb)1713 ModifierFolding::visit(BasicBlock *bb)
1714 {
1715    const Target *target = prog->getTarget();
1716 
1717    Instruction *i, *next, *mi;
1718    Modifier mod;
1719 
1720    for (i = bb->getEntry(); i; i = next) {
1721       next = i->next;
1722 
1723       if (0 && i->op == OP_SUB) {
1724          // turn "sub" into "add neg" (do we really want this ?)
1725          i->op = OP_ADD;
1726          i->src(0).mod = i->src(0).mod ^ Modifier(NV50_IR_MOD_NEG);
1727       }
1728 
1729       for (int s = 0; s < 3 && i->srcExists(s); ++s) {
1730          mi = i->getSrc(s)->getInsn();
1731          if (!mi ||
1732              mi->predSrc >= 0 || mi->getDef(0)->refCount() > 8)
1733             continue;
1734          if (i->sType == TYPE_U32 && mi->dType == TYPE_S32) {
1735             if ((i->op != OP_ADD &&
1736                  i->op != OP_MUL) ||
1737                 (mi->op != OP_ABS &&
1738                  mi->op != OP_NEG))
1739                continue;
1740          } else
1741          if (i->sType != mi->dType) {
1742             continue;
1743          }
1744          if ((mod = Modifier(mi->op)) == Modifier(0))
1745             continue;
1746          mod *= mi->src(0).mod;
1747 
1748          if ((i->op == OP_ABS) || i->src(s).mod.abs()) {
1749             // abs neg [abs] = abs
1750             mod = mod & Modifier(~(NV50_IR_MOD_NEG | NV50_IR_MOD_ABS));
1751          } else
1752          if ((i->op == OP_NEG) && mod.neg()) {
1753             assert(s == 0);
1754             // neg as both opcode and modifier on same insn is prohibited
1755             // neg neg abs = abs, neg neg = identity
1756             mod = mod & Modifier(~NV50_IR_MOD_NEG);
1757             i->op = mod.getOp();
1758             mod = mod & Modifier(~NV50_IR_MOD_ABS);
1759             if (mod == Modifier(0))
1760                i->op = OP_MOV;
1761          }
1762 
1763          if (target->isModSupported(i, s, mod)) {
1764             i->setSrc(s, mi->getSrc(0));
1765             i->src(s).mod *= mod;
1766          }
1767       }
1768 
1769       if (i->op == OP_SAT) {
1770          mi = i->getSrc(0)->getInsn();
1771          if (mi &&
1772              mi->getDef(0)->refCount() <= 1 && target->isSatSupported(mi)) {
1773             mi->saturate = 1;
1774             mi->setDef(0, i->getDef(0));
1775             delete_Instruction(prog, i);
1776          }
1777       }
1778    }
1779 
1780    return true;
1781 }
1782 
1783 // =============================================================================
1784 
1785 // MUL + ADD -> MAD/FMA
1786 // MIN/MAX(a, a) -> a, etc.
1787 // SLCT(a, b, const) -> cc(const) ? a : b
1788 // RCP(RCP(a)) -> a
1789 // MUL(MUL(a, b), const) -> MUL_Xconst(a, b)
1790 // EXTBF(RDSV(COMBINED_TID)) -> RDSV(TID)
1791 class AlgebraicOpt : public Pass
1792 {
1793 private:
1794    virtual bool visit(BasicBlock *);
1795 
1796    void handleABS(Instruction *);
1797    bool handleADD(Instruction *);
1798    bool tryADDToMADOrSAD(Instruction *, operation toOp);
1799    void handleMINMAX(Instruction *);
1800    void handleRCP(Instruction *);
1801    void handleSLCT(Instruction *);
1802    void handleLOGOP(Instruction *);
1803    void handleCVT_NEG(Instruction *);
1804    void handleCVT_CVT(Instruction *);
1805    void handleCVT_EXTBF(Instruction *);
1806    void handleSUCLAMP(Instruction *);
1807    void handleNEG(Instruction *);
1808    void handleEXTBF_RDSV(Instruction *);
1809 
1810    BuildUtil bld;
1811 };
1812 
1813 void
handleABS(Instruction * abs)1814 AlgebraicOpt::handleABS(Instruction *abs)
1815 {
1816    Instruction *sub = abs->getSrc(0)->getInsn();
1817    DataType ty;
1818    if (!sub ||
1819        !prog->getTarget()->isOpSupported(OP_SAD, abs->dType))
1820       return;
1821    // expect not to have mods yet, if we do, bail
1822    if (sub->src(0).mod || sub->src(1).mod)
1823       return;
1824    // hidden conversion ?
1825    ty = intTypeToSigned(sub->dType);
1826    if (abs->dType != abs->sType || ty != abs->sType)
1827       return;
1828 
1829    if ((sub->op != OP_ADD && sub->op != OP_SUB) ||
1830        sub->src(0).getFile() != FILE_GPR || sub->src(0).mod ||
1831        sub->src(1).getFile() != FILE_GPR || sub->src(1).mod)
1832          return;
1833 
1834    Value *src0 = sub->getSrc(0);
1835    Value *src1 = sub->getSrc(1);
1836 
1837    if (sub->op == OP_ADD) {
1838       Instruction *neg = sub->getSrc(1)->getInsn();
1839       if (neg && neg->op != OP_NEG) {
1840          neg = sub->getSrc(0)->getInsn();
1841          src0 = sub->getSrc(1);
1842       }
1843       if (!neg || neg->op != OP_NEG ||
1844           neg->dType != neg->sType || neg->sType != ty)
1845          return;
1846       src1 = neg->getSrc(0);
1847    }
1848 
1849    // found ABS(SUB))
1850    abs->moveSources(1, 2); // move sources >=1 up by 2
1851    abs->op = OP_SAD;
1852    abs->setType(sub->dType);
1853    abs->setSrc(0, src0);
1854    abs->setSrc(1, src1);
1855    bld.setPosition(abs, false);
1856    abs->setSrc(2, bld.loadImm(bld.getSSA(typeSizeof(ty)), 0));
1857 }
1858 
1859 bool
handleADD(Instruction * add)1860 AlgebraicOpt::handleADD(Instruction *add)
1861 {
1862    Value *src0 = add->getSrc(0);
1863    Value *src1 = add->getSrc(1);
1864 
1865    if (src0->reg.file != FILE_GPR || src1->reg.file != FILE_GPR)
1866       return false;
1867 
1868    bool changed = false;
1869    // we can't optimize to MAD if the add is precise
1870    if (!add->precise && prog->getTarget()->isOpSupported(OP_MAD, add->dType))
1871       changed = tryADDToMADOrSAD(add, OP_MAD);
1872    if (!changed && prog->getTarget()->isOpSupported(OP_SAD, add->dType))
1873       changed = tryADDToMADOrSAD(add, OP_SAD);
1874    return changed;
1875 }
1876 
1877 // ADD(SAD(a,b,0), c) -> SAD(a,b,c)
1878 // ADD(MUL(a,b), c) -> MAD(a,b,c)
1879 bool
tryADDToMADOrSAD(Instruction * add,operation toOp)1880 AlgebraicOpt::tryADDToMADOrSAD(Instruction *add, operation toOp)
1881 {
1882    Value *src0 = add->getSrc(0);
1883    Value *src1 = add->getSrc(1);
1884    Value *src;
1885    int s;
1886    const operation srcOp = toOp == OP_SAD ? OP_SAD : OP_MUL;
1887    const Modifier modBad = Modifier(~((toOp == OP_MAD) ? NV50_IR_MOD_NEG : 0));
1888    Modifier mod[4];
1889 
1890    if (src0->refCount() == 1 &&
1891        src0->getUniqueInsn() && src0->getUniqueInsn()->op == srcOp)
1892       s = 0;
1893    else
1894    if (src1->refCount() == 1 &&
1895        src1->getUniqueInsn() && src1->getUniqueInsn()->op == srcOp)
1896       s = 1;
1897    else
1898       return false;
1899 
1900    src = add->getSrc(s);
1901 
1902    if (src->getUniqueInsn() && src->getUniqueInsn()->bb != add->bb)
1903       return false;
1904 
1905    if (src->getInsn()->saturate || src->getInsn()->postFactor ||
1906        src->getInsn()->dnz || src->getInsn()->precise)
1907       return false;
1908 
1909    if (toOp == OP_SAD) {
1910       ImmediateValue imm;
1911       if (!src->getInsn()->src(2).getImmediate(imm))
1912          return false;
1913       if (!imm.isInteger(0))
1914          return false;
1915    }
1916 
1917    if (typeSizeof(add->dType) != typeSizeof(src->getInsn()->dType) ||
1918        isFloatType(add->dType) != isFloatType(src->getInsn()->dType))
1919       return false;
1920 
1921    mod[0] = add->src(0).mod;
1922    mod[1] = add->src(1).mod;
1923    mod[2] = src->getUniqueInsn()->src(0).mod;
1924    mod[3] = src->getUniqueInsn()->src(1).mod;
1925 
1926    if (((mod[0] | mod[1]) | (mod[2] | mod[3])) & modBad)
1927       return false;
1928 
1929    add->op = toOp;
1930    add->subOp = src->getInsn()->subOp; // potentially mul-high
1931    add->dnz = src->getInsn()->dnz;
1932    add->dType = src->getInsn()->dType; // sign matters for imad hi
1933    add->sType = src->getInsn()->sType;
1934 
1935    add->setSrc(2, add->src(s ? 0 : 1));
1936 
1937    add->setSrc(0, src->getInsn()->getSrc(0));
1938    add->src(0).mod = mod[2] ^ mod[s];
1939    add->setSrc(1, src->getInsn()->getSrc(1));
1940    add->src(1).mod = mod[3];
1941 
1942    return true;
1943 }
1944 
1945 void
handleMINMAX(Instruction * minmax)1946 AlgebraicOpt::handleMINMAX(Instruction *minmax)
1947 {
1948    Value *src0 = minmax->getSrc(0);
1949    Value *src1 = minmax->getSrc(1);
1950 
1951    if (src0 != src1 || src0->reg.file != FILE_GPR)
1952       return;
1953    if (minmax->src(0).mod == minmax->src(1).mod) {
1954       if (minmax->def(0).mayReplace(minmax->src(0))) {
1955          minmax->def(0).replace(minmax->src(0), false);
1956          delete_Instruction(prog, minmax);
1957       } else {
1958          minmax->op = OP_CVT;
1959          minmax->setSrc(1, NULL);
1960       }
1961    } else {
1962       // TODO:
1963       // min(x, -x) = -abs(x)
1964       // min(x, -abs(x)) = -abs(x)
1965       // min(x, abs(x)) = x
1966       // max(x, -abs(x)) = x
1967       // max(x, abs(x)) = abs(x)
1968       // max(x, -x) = abs(x)
1969    }
1970 }
1971 
1972 // rcp(rcp(a)) = a
1973 // rcp(sqrt(a)) = rsq(a)
1974 void
handleRCP(Instruction * rcp)1975 AlgebraicOpt::handleRCP(Instruction *rcp)
1976 {
1977    Instruction *si = rcp->getSrc(0)->getUniqueInsn();
1978 
1979    if (!si)
1980       return;
1981 
1982    if (si->op == OP_RCP) {
1983       Modifier mod = rcp->src(0).mod * si->src(0).mod;
1984       rcp->op = mod.getOp();
1985       rcp->setSrc(0, si->getSrc(0));
1986    } else if (si->op == OP_SQRT) {
1987       rcp->op = OP_RSQ;
1988       rcp->setSrc(0, si->getSrc(0));
1989       rcp->src(0).mod = rcp->src(0).mod * si->src(0).mod;
1990    }
1991 }
1992 
1993 void
handleSLCT(Instruction * slct)1994 AlgebraicOpt::handleSLCT(Instruction *slct)
1995 {
1996    if (slct->getSrc(2)->reg.file == FILE_IMMEDIATE) {
1997       if (slct->getSrc(2)->asImm()->compare(slct->asCmp()->setCond, 0.0f))
1998          slct->setSrc(0, slct->getSrc(1));
1999    } else
2000    if (slct->getSrc(0) != slct->getSrc(1)) {
2001       return;
2002    }
2003    slct->op = OP_MOV;
2004    slct->setSrc(1, NULL);
2005    slct->setSrc(2, NULL);
2006 }
2007 
2008 void
handleLOGOP(Instruction * logop)2009 AlgebraicOpt::handleLOGOP(Instruction *logop)
2010 {
2011    Value *src0 = logop->getSrc(0);
2012    Value *src1 = logop->getSrc(1);
2013 
2014    if (src0->reg.file != FILE_GPR || src1->reg.file != FILE_GPR)
2015       return;
2016 
2017    if (src0 == src1) {
2018       if ((logop->op == OP_AND || logop->op == OP_OR) &&
2019           logop->def(0).mayReplace(logop->src(0))) {
2020          logop->def(0).replace(logop->src(0), false);
2021          delete_Instruction(prog, logop);
2022       }
2023    } else {
2024       // try AND(SET, SET) -> SET_AND(SET)
2025       Instruction *set0 = src0->getInsn();
2026       Instruction *set1 = src1->getInsn();
2027 
2028       if (!set0 || set0->fixed || !set1 || set1->fixed)
2029          return;
2030       if (set1->op != OP_SET) {
2031          Instruction *xchg = set0;
2032          set0 = set1;
2033          set1 = xchg;
2034          if (set1->op != OP_SET)
2035             return;
2036       }
2037       operation redOp = (logop->op == OP_AND ? OP_SET_AND :
2038                          logop->op == OP_XOR ? OP_SET_XOR : OP_SET_OR);
2039       if (!prog->getTarget()->isOpSupported(redOp, set1->sType))
2040          return;
2041       if (set0->op != OP_SET &&
2042           set0->op != OP_SET_AND &&
2043           set0->op != OP_SET_OR &&
2044           set0->op != OP_SET_XOR)
2045          return;
2046       if (set0->getDef(0)->refCount() > 1 &&
2047           set1->getDef(0)->refCount() > 1)
2048          return;
2049       if (set0->getPredicate() || set1->getPredicate())
2050          return;
2051       // check that they don't source each other
2052       for (int s = 0; s < 2; ++s)
2053          if (set0->getSrc(s) == set1->getDef(0) ||
2054              set1->getSrc(s) == set0->getDef(0))
2055             return;
2056 
2057       set0 = cloneForward(func, set0);
2058       set1 = cloneShallow(func, set1);
2059       logop->bb->insertAfter(logop, set1);
2060       logop->bb->insertAfter(logop, set0);
2061 
2062       set0->dType = TYPE_U8;
2063       set0->getDef(0)->reg.file = FILE_PREDICATE;
2064       set0->getDef(0)->reg.size = 1;
2065       set1->setSrc(2, set0->getDef(0));
2066       set1->op = redOp;
2067       set1->setDef(0, logop->getDef(0));
2068       delete_Instruction(prog, logop);
2069    }
2070 }
2071 
2072 // F2I(NEG(SET with result 1.0f/0.0f)) -> SET with result -1/0
2073 // nv50:
2074 //  F2I(NEG(I2F(ABS(SET))))
2075 void
handleCVT_NEG(Instruction * cvt)2076 AlgebraicOpt::handleCVT_NEG(Instruction *cvt)
2077 {
2078    Instruction *insn = cvt->getSrc(0)->getInsn();
2079    if (cvt->sType != TYPE_F32 ||
2080        cvt->dType != TYPE_S32 || cvt->src(0).mod != Modifier(0))
2081       return;
2082    if (!insn || insn->op != OP_NEG || insn->dType != TYPE_F32)
2083       return;
2084    if (insn->src(0).mod != Modifier(0))
2085       return;
2086    insn = insn->getSrc(0)->getInsn();
2087 
2088    // check for nv50 SET(-1,0) -> SET(1.0f/0.0f) chain and nvc0's f32 SET
2089    if (insn && insn->op == OP_CVT &&
2090        insn->dType == TYPE_F32 &&
2091        insn->sType == TYPE_S32) {
2092       insn = insn->getSrc(0)->getInsn();
2093       if (!insn || insn->op != OP_ABS || insn->sType != TYPE_S32 ||
2094           insn->src(0).mod)
2095          return;
2096       insn = insn->getSrc(0)->getInsn();
2097       if (!insn || insn->op != OP_SET || insn->dType != TYPE_U32)
2098          return;
2099    } else
2100    if (!insn || insn->op != OP_SET || insn->dType != TYPE_F32) {
2101       return;
2102    }
2103 
2104    Instruction *bset = cloneShallow(func, insn);
2105    bset->dType = TYPE_U32;
2106    bset->setDef(0, cvt->getDef(0));
2107    cvt->bb->insertAfter(cvt, bset);
2108    delete_Instruction(prog, cvt);
2109 }
2110 
2111 // F2I(TRUNC()) and so on can be expressed as a single CVT. If the earlier CVT
2112 // does a type conversion, this becomes trickier as there might be range
2113 // changes/etc. We could handle those in theory as long as the range was being
2114 // reduced or kept the same.
2115 void
handleCVT_CVT(Instruction * cvt)2116 AlgebraicOpt::handleCVT_CVT(Instruction *cvt)
2117 {
2118    Instruction *insn = cvt->getSrc(0)->getInsn();
2119 
2120    if (!insn ||
2121        insn->saturate ||
2122        insn->subOp ||
2123        insn->dType != insn->sType ||
2124        insn->dType != cvt->sType)
2125       return;
2126 
2127    RoundMode rnd = insn->rnd;
2128    switch (insn->op) {
2129    case OP_CEIL:
2130       rnd = ROUND_PI;
2131       break;
2132    case OP_FLOOR:
2133       rnd = ROUND_MI;
2134       break;
2135    case OP_TRUNC:
2136       rnd = ROUND_ZI;
2137       break;
2138    case OP_CVT:
2139       break;
2140    default:
2141       return;
2142    }
2143 
2144    if (!isFloatType(cvt->dType) || !isFloatType(insn->sType))
2145       rnd = (RoundMode)(rnd & 3);
2146 
2147    cvt->rnd = rnd;
2148    cvt->setSrc(0, insn->getSrc(0));
2149    cvt->src(0).mod *= insn->src(0).mod;
2150    cvt->sType = insn->sType;
2151 }
2152 
2153 // Some shaders extract packed bytes out of words and convert them to
2154 // e.g. float. The Fermi+ CVT instruction can extract those directly, as can
2155 // nv50 for word sizes.
2156 //
2157 // CVT(EXTBF(x, byte/word))
2158 // CVT(AND(bytemask, x))
2159 // CVT(AND(bytemask, SHR(x, 8/16/24)))
2160 // CVT(SHR(x, 16/24))
2161 void
handleCVT_EXTBF(Instruction * cvt)2162 AlgebraicOpt::handleCVT_EXTBF(Instruction *cvt)
2163 {
2164    Instruction *insn = cvt->getSrc(0)->getInsn();
2165    ImmediateValue imm;
2166    Value *arg = NULL;
2167    unsigned width, offset;
2168    if ((cvt->sType != TYPE_U32 && cvt->sType != TYPE_S32) || !insn)
2169       return;
2170    if (insn->op == OP_EXTBF && insn->src(1).getImmediate(imm)) {
2171       width = (imm.reg.data.u32 >> 8) & 0xff;
2172       offset = imm.reg.data.u32 & 0xff;
2173       arg = insn->getSrc(0);
2174 
2175       if (width != 8 && width != 16)
2176          return;
2177       if (width == 8 && offset & 0x7)
2178          return;
2179       if (width == 16 && offset & 0xf)
2180          return;
2181    } else if (insn->op == OP_AND) {
2182       int s;
2183       if (insn->src(0).getImmediate(imm))
2184          s = 0;
2185       else if (insn->src(1).getImmediate(imm))
2186          s = 1;
2187       else
2188          return;
2189 
2190       if (imm.reg.data.u32 == 0xff)
2191          width = 8;
2192       else if (imm.reg.data.u32 == 0xffff)
2193          width = 16;
2194       else
2195          return;
2196 
2197       arg = insn->getSrc(!s);
2198       Instruction *shift = arg->getInsn();
2199       offset = 0;
2200       if (shift && shift->op == OP_SHR &&
2201           shift->sType == cvt->sType &&
2202           shift->src(1).getImmediate(imm) &&
2203           ((width == 8 && (imm.reg.data.u32 & 0x7) == 0) ||
2204            (width == 16 && (imm.reg.data.u32 & 0xf) == 0))) {
2205          arg = shift->getSrc(0);
2206          offset = imm.reg.data.u32;
2207       }
2208       // We just AND'd the high bits away, which means this is effectively an
2209       // unsigned value.
2210       cvt->sType = TYPE_U32;
2211    } else if (insn->op == OP_SHR &&
2212               insn->sType == cvt->sType &&
2213               insn->src(1).getImmediate(imm)) {
2214       arg = insn->getSrc(0);
2215       if (imm.reg.data.u32 == 24) {
2216          width = 8;
2217          offset = 24;
2218       } else if (imm.reg.data.u32 == 16) {
2219          width = 16;
2220          offset = 16;
2221       } else {
2222          return;
2223       }
2224    }
2225 
2226    if (!arg)
2227       return;
2228 
2229    // Irrespective of what came earlier, we can undo a shift on the argument
2230    // by adjusting the offset.
2231    Instruction *shift = arg->getInsn();
2232    if (shift && shift->op == OP_SHL &&
2233        shift->src(1).getImmediate(imm) &&
2234        ((width == 8 && (imm.reg.data.u32 & 0x7) == 0) ||
2235         (width == 16 && (imm.reg.data.u32 & 0xf) == 0)) &&
2236        imm.reg.data.u32 <= offset) {
2237       arg = shift->getSrc(0);
2238       offset -= imm.reg.data.u32;
2239    }
2240 
2241    // The unpackSnorm lowering still leaves a few shifts behind, but it's too
2242    // annoying to detect them.
2243 
2244    if (width == 8) {
2245       cvt->sType = cvt->sType == TYPE_U32 ? TYPE_U8 : TYPE_S8;
2246    } else {
2247       assert(width == 16);
2248       cvt->sType = cvt->sType == TYPE_U32 ? TYPE_U16 : TYPE_S16;
2249    }
2250    cvt->setSrc(0, arg);
2251    cvt->subOp = offset >> 3;
2252 }
2253 
2254 // SUCLAMP dst, (ADD b imm), k, 0 -> SUCLAMP dst, b, k, imm (if imm fits s6)
2255 void
handleSUCLAMP(Instruction * insn)2256 AlgebraicOpt::handleSUCLAMP(Instruction *insn)
2257 {
2258    ImmediateValue imm;
2259    int32_t val = insn->getSrc(2)->asImm()->reg.data.s32;
2260    int s;
2261    Instruction *add;
2262 
2263    assert(insn->srcExists(0) && insn->src(0).getFile() == FILE_GPR);
2264 
2265    // look for ADD (TODO: only count references by non-SUCLAMP)
2266    if (insn->getSrc(0)->refCount() > 1)
2267       return;
2268    add = insn->getSrc(0)->getInsn();
2269    if (!add || add->op != OP_ADD ||
2270        (add->dType != TYPE_U32 &&
2271         add->dType != TYPE_S32))
2272       return;
2273 
2274    // look for immediate
2275    for (s = 0; s < 2; ++s)
2276       if (add->src(s).getImmediate(imm))
2277          break;
2278    if (s >= 2)
2279       return;
2280    s = s ? 0 : 1;
2281    // determine if immediate fits
2282    val += imm.reg.data.s32;
2283    if (val > 31 || val < -32)
2284       return;
2285    // determine if other addend fits
2286    if (add->src(s).getFile() != FILE_GPR || add->src(s).mod != Modifier(0))
2287       return;
2288 
2289    bld.setPosition(insn, false); // make sure bld is init'ed
2290    // replace sources
2291    insn->setSrc(2, bld.mkImm(val));
2292    insn->setSrc(0, add->getSrc(s));
2293 }
2294 
2295 // NEG(AND(SET, 1)) -> SET
2296 void
handleNEG(Instruction * i)2297 AlgebraicOpt::handleNEG(Instruction *i) {
2298    Instruction *src = i->getSrc(0)->getInsn();
2299    ImmediateValue imm;
2300    int b;
2301 
2302    if (isFloatType(i->sType) || !src || src->op != OP_AND)
2303       return;
2304 
2305    if (src->src(0).getImmediate(imm))
2306       b = 1;
2307    else if (src->src(1).getImmediate(imm))
2308       b = 0;
2309    else
2310       return;
2311 
2312    if (!imm.isInteger(1))
2313       return;
2314 
2315    Instruction *set = src->getSrc(b)->getInsn();
2316    if ((set->op == OP_SET || set->op == OP_SET_AND ||
2317        set->op == OP_SET_OR || set->op == OP_SET_XOR) &&
2318        !isFloatType(set->dType)) {
2319       i->def(0).replace(set->getDef(0), false);
2320    }
2321 }
2322 
2323 // EXTBF(RDSV(COMBINED_TID)) -> RDSV(TID)
2324 void
handleEXTBF_RDSV(Instruction * i)2325 AlgebraicOpt::handleEXTBF_RDSV(Instruction *i)
2326 {
2327    Instruction *rdsv = i->getSrc(0)->getUniqueInsn();
2328    if (rdsv->op != OP_RDSV ||
2329        rdsv->getSrc(0)->asSym()->reg.data.sv.sv != SV_COMBINED_TID)
2330       return;
2331    // Avoid creating more RDSV instructions
2332    if (rdsv->getDef(0)->refCount() > 1)
2333       return;
2334 
2335    ImmediateValue imm;
2336    if (!i->src(1).getImmediate(imm))
2337       return;
2338 
2339    int index;
2340    if (imm.isInteger(0x1000))
2341       index = 0;
2342    else
2343    if (imm.isInteger(0x0a10))
2344       index = 1;
2345    else
2346    if (imm.isInteger(0x061a))
2347       index = 2;
2348    else
2349       return;
2350 
2351    bld.setPosition(i, false);
2352 
2353    i->op = OP_RDSV;
2354    i->setSrc(0, bld.mkSysVal(SV_TID, index));
2355    i->setSrc(1, NULL);
2356 }
2357 
2358 bool
visit(BasicBlock * bb)2359 AlgebraicOpt::visit(BasicBlock *bb)
2360 {
2361    Instruction *next;
2362    for (Instruction *i = bb->getEntry(); i; i = next) {
2363       next = i->next;
2364       switch (i->op) {
2365       case OP_ABS:
2366          handleABS(i);
2367          break;
2368       case OP_ADD:
2369          handleADD(i);
2370          break;
2371       case OP_RCP:
2372          handleRCP(i);
2373          break;
2374       case OP_MIN:
2375       case OP_MAX:
2376          handleMINMAX(i);
2377          break;
2378       case OP_SLCT:
2379          handleSLCT(i);
2380          break;
2381       case OP_AND:
2382       case OP_OR:
2383       case OP_XOR:
2384          handleLOGOP(i);
2385          break;
2386       case OP_CVT:
2387          handleCVT_NEG(i);
2388          handleCVT_CVT(i);
2389          if (prog->getTarget()->isOpSupported(OP_EXTBF, TYPE_U32))
2390              handleCVT_EXTBF(i);
2391          break;
2392       case OP_SUCLAMP:
2393          handleSUCLAMP(i);
2394          break;
2395       case OP_NEG:
2396          handleNEG(i);
2397          break;
2398       case OP_EXTBF:
2399          handleEXTBF_RDSV(i);
2400          break;
2401       default:
2402          break;
2403       }
2404    }
2405 
2406    return true;
2407 }
2408 
2409 // =============================================================================
2410 
2411 // ADD(SHL(a, b), c) -> SHLADD(a, b, c)
2412 // MUL(a, b) -> a few XMADs
2413 // MAD/FMA(a, b, c) -> a few XMADs
2414 class LateAlgebraicOpt : public Pass
2415 {
2416 private:
2417    virtual bool visit(Instruction *);
2418 
2419    void handleADD(Instruction *);
2420    void handleMULMAD(Instruction *);
2421    bool tryADDToSHLADD(Instruction *);
2422 
2423    BuildUtil bld;
2424 };
2425 
2426 void
handleADD(Instruction * add)2427 LateAlgebraicOpt::handleADD(Instruction *add)
2428 {
2429    Value *src0 = add->getSrc(0);
2430    Value *src1 = add->getSrc(1);
2431 
2432    if (src0->reg.file != FILE_GPR || src1->reg.file != FILE_GPR)
2433       return;
2434 
2435    if (prog->getTarget()->isOpSupported(OP_SHLADD, add->dType))
2436       tryADDToSHLADD(add);
2437 }
2438 
2439 // ADD(SHL(a, b), c) -> SHLADD(a, b, c)
2440 bool
tryADDToSHLADD(Instruction * add)2441 LateAlgebraicOpt::tryADDToSHLADD(Instruction *add)
2442 {
2443    Value *src0 = add->getSrc(0);
2444    Value *src1 = add->getSrc(1);
2445    ImmediateValue imm;
2446    Instruction *shl;
2447    Value *src;
2448    int s;
2449 
2450    if (add->saturate || add->usesFlags() || typeSizeof(add->dType) == 8
2451        || isFloatType(add->dType))
2452       return false;
2453 
2454    if (src0->getUniqueInsn() && src0->getUniqueInsn()->op == OP_SHL)
2455       s = 0;
2456    else
2457    if (src1->getUniqueInsn() && src1->getUniqueInsn()->op == OP_SHL)
2458       s = 1;
2459    else
2460       return false;
2461 
2462    src = add->getSrc(s);
2463    shl = src->getUniqueInsn();
2464 
2465    if (shl->bb != add->bb || shl->usesFlags() || shl->subOp || shl->src(0).mod)
2466       return false;
2467 
2468    if (!shl->src(1).getImmediate(imm))
2469       return false;
2470 
2471    add->op = OP_SHLADD;
2472    add->setSrc(2, add->src(!s));
2473    // SHL can't have any modifiers, but the ADD source may have had
2474    // one. Preserve it.
2475    add->setSrc(0, shl->getSrc(0));
2476    if (s == 1)
2477       add->src(0).mod = add->src(1).mod;
2478    add->setSrc(1, new_ImmediateValue(shl->bb->getProgram(), imm.reg.data.u32));
2479    add->src(1).mod = Modifier(0);
2480 
2481    return true;
2482 }
2483 
2484 // MUL(a, b) -> a few XMADs
2485 // MAD/FMA(a, b, c) -> a few XMADs
2486 void
handleMULMAD(Instruction * i)2487 LateAlgebraicOpt::handleMULMAD(Instruction *i)
2488 {
2489    // TODO: handle NV50_IR_SUBOP_MUL_HIGH
2490    if (!prog->getTarget()->isOpSupported(OP_XMAD, TYPE_U32))
2491       return;
2492    if (isFloatType(i->dType) || typeSizeof(i->dType) != 4)
2493       return;
2494    if (i->subOp || i->usesFlags() || i->flagsDef >= 0)
2495       return;
2496 
2497    assert(!i->src(0).mod);
2498    assert(!i->src(1).mod);
2499    assert(i->op == OP_MUL ? 1 : !i->src(2).mod);
2500 
2501    bld.setPosition(i, false);
2502 
2503    Value *a = i->getSrc(0);
2504    Value *b = i->getSrc(1);
2505    Value *c = i->op == OP_MUL ? bld.mkImm(0) : i->getSrc(2);
2506 
2507    Value *tmp0 = bld.getSSA();
2508    Value *tmp1 = bld.getSSA();
2509 
2510    Instruction *insn = bld.mkOp3(OP_XMAD, TYPE_U32, tmp0, b, a, c);
2511    insn->setPredicate(i->cc, i->getPredicate());
2512 
2513    insn = bld.mkOp3(OP_XMAD, TYPE_U32, tmp1, b, a, bld.mkImm(0));
2514    insn->setPredicate(i->cc, i->getPredicate());
2515    insn->subOp = NV50_IR_SUBOP_XMAD_MRG | NV50_IR_SUBOP_XMAD_H1(1);
2516 
2517    Value *pred = i->getPredicate();
2518    i->setPredicate(i->cc, NULL);
2519 
2520    i->op = OP_XMAD;
2521    i->setSrc(0, b);
2522    i->setSrc(1, tmp1);
2523    i->setSrc(2, tmp0);
2524    i->subOp = NV50_IR_SUBOP_XMAD_PSL | NV50_IR_SUBOP_XMAD_CBCC;
2525    i->subOp |= NV50_IR_SUBOP_XMAD_H1(0) | NV50_IR_SUBOP_XMAD_H1(1);
2526 
2527    i->setPredicate(i->cc, pred);
2528 }
2529 
2530 bool
visit(Instruction * i)2531 LateAlgebraicOpt::visit(Instruction *i)
2532 {
2533    switch (i->op) {
2534    case OP_ADD:
2535       handleADD(i);
2536       break;
2537    case OP_MUL:
2538    case OP_MAD:
2539    case OP_FMA:
2540       handleMULMAD(i);
2541       break;
2542    default:
2543       break;
2544    }
2545 
2546    return true;
2547 }
2548 
2549 // =============================================================================
2550 
2551 // Split 64-bit MUL and MAD
2552 class Split64BitOpPreRA : public Pass
2553 {
2554 private:
2555    virtual bool visit(BasicBlock *);
2556    void split64MulMad(Function *, Instruction *, DataType);
2557 
2558    BuildUtil bld;
2559 };
2560 
2561 bool
visit(BasicBlock * bb)2562 Split64BitOpPreRA::visit(BasicBlock *bb)
2563 {
2564    Instruction *i, *next;
2565    Modifier mod;
2566 
2567    for (i = bb->getEntry(); i; i = next) {
2568       next = i->next;
2569 
2570       DataType hTy;
2571       switch (i->dType) {
2572       case TYPE_U64: hTy = TYPE_U32; break;
2573       case TYPE_S64: hTy = TYPE_S32; break;
2574       default:
2575          continue;
2576       }
2577 
2578       if (i->op == OP_MAD || i->op == OP_MUL)
2579          split64MulMad(func, i, hTy);
2580    }
2581 
2582    return true;
2583 }
2584 
2585 void
split64MulMad(Function * fn,Instruction * i,DataType hTy)2586 Split64BitOpPreRA::split64MulMad(Function *fn, Instruction *i, DataType hTy)
2587 {
2588    assert(i->op == OP_MAD || i->op == OP_MUL);
2589    assert(!isFloatType(i->dType) && !isFloatType(i->sType));
2590    assert(typeSizeof(hTy) == 4);
2591 
2592    bld.setPosition(i, true);
2593 
2594    Value *zero = bld.mkImm(0u);
2595    Value *carry = bld.getSSA(1, FILE_FLAGS);
2596 
2597    // We want to compute `d = a * b (+ c)?`, where a, b, c and d are 64-bit
2598    // values (a, b and c might be 32-bit values), using 32-bit operations. This
2599    // gives the following operations:
2600    // * `d.low = low(a.low * b.low) (+ c.low)?`
2601    // * `d.high = low(a.high * b.low) + low(a.low * b.high)
2602    //           + high(a.low * b.low) (+ c.high)?`
2603    //
2604    // To compute the high bits, we can split in the following operations:
2605    // * `tmp1   = low(a.high * b.low) (+ c.high)?`
2606    // * `tmp2   = low(a.low * b.high) + tmp1`
2607    // * `d.high = high(a.low * b.low) + tmp2`
2608    //
2609    // mkSplit put lower bits at index 0 and higher bits at index 1
2610 
2611    Value *op1[2];
2612    if (i->getSrc(0)->reg.size == 8)
2613       bld.mkSplit(op1, 4, i->getSrc(0));
2614    else {
2615       op1[0] = i->getSrc(0);
2616       op1[1] = zero;
2617    }
2618    Value *op2[2];
2619    if (i->getSrc(1)->reg.size == 8)
2620       bld.mkSplit(op2, 4, i->getSrc(1));
2621    else {
2622       op2[0] = i->getSrc(1);
2623       op2[1] = zero;
2624    }
2625 
2626    Value *op3[2] = { NULL, NULL };
2627    if (i->op == OP_MAD) {
2628       if (i->getSrc(2)->reg.size == 8)
2629          bld.mkSplit(op3, 4, i->getSrc(2));
2630       else {
2631          op3[0] = i->getSrc(2);
2632          op3[1] = zero;
2633       }
2634    }
2635 
2636    Value *tmpRes1Hi = bld.getSSA();
2637    if (i->op == OP_MAD)
2638       bld.mkOp3(OP_MAD, hTy, tmpRes1Hi, op1[1], op2[0], op3[1]);
2639    else
2640       bld.mkOp2(OP_MUL, hTy, tmpRes1Hi, op1[1], op2[0]);
2641 
2642    Value *tmpRes2Hi = bld.mkOp3v(OP_MAD, hTy, bld.getSSA(), op1[0], op2[1], tmpRes1Hi);
2643 
2644    Value *def[2] = { bld.getSSA(), bld.getSSA() };
2645 
2646    // If it was a MAD, add the carry from the low bits
2647    // It is not needed if it was a MUL, since we added high(a.low * b.low) to
2648    // d.high
2649    if (i->op == OP_MAD)
2650       bld.mkOp3(OP_MAD, hTy, def[0], op1[0], op2[0], op3[0])->setFlagsDef(1, carry);
2651    else
2652       bld.mkOp2(OP_MUL, hTy, def[0], op1[0], op2[0]);
2653 
2654    Instruction *hiPart3 = bld.mkOp3(OP_MAD, hTy, def[1], op1[0], op2[0], tmpRes2Hi);
2655    hiPart3->subOp = NV50_IR_SUBOP_MUL_HIGH;
2656    if (i->op == OP_MAD)
2657       hiPart3->setFlagsSrc(3, carry);
2658 
2659    bld.mkOp2(OP_MERGE, i->dType, i->getDef(0), def[0], def[1]);
2660 
2661    delete_Instruction(fn->getProgram(), i);
2662 }
2663 
2664 // =============================================================================
2665 
2666 static inline void
updateLdStOffset(Instruction * ldst,int32_t offset,Function * fn)2667 updateLdStOffset(Instruction *ldst, int32_t offset, Function *fn)
2668 {
2669    if (offset != ldst->getSrc(0)->reg.data.offset) {
2670       if (ldst->getSrc(0)->refCount() > 1)
2671          ldst->setSrc(0, cloneShallow(fn, ldst->getSrc(0)));
2672       ldst->getSrc(0)->reg.data.offset = offset;
2673    }
2674 }
2675 
2676 // Combine loads and stores, forward stores to loads where possible.
2677 class MemoryOpt : public Pass
2678 {
2679 private:
2680    class Record
2681    {
2682    public:
2683       Record *next;
2684       Instruction *insn;
2685       const Value *rel[2];
2686       const Value *base;
2687       int32_t offset;
2688       int8_t fileIndex;
2689       uint8_t size;
2690       bool locked;
2691       Record *prev;
2692 
2693       bool overlaps(const Instruction *ldst) const;
2694 
2695       inline void link(Record **);
2696       inline void unlink(Record **);
2697       inline void set(const Instruction *ldst);
2698    };
2699 
2700 public:
2701    MemoryOpt();
2702 
2703    Record *loads[DATA_FILE_COUNT];
2704    Record *stores[DATA_FILE_COUNT];
2705 
2706    MemoryPool recordPool;
2707 
2708 private:
2709    virtual bool visit(BasicBlock *);
2710    bool runOpt(BasicBlock *);
2711 
2712    Record **getList(const Instruction *);
2713 
2714    Record *findRecord(const Instruction *, bool load, bool& isAdjacent) const;
2715 
2716    // merge @insn into load/store instruction from @rec
2717    bool combineLd(Record *rec, Instruction *ld);
2718    bool combineSt(Record *rec, Instruction *st);
2719 
2720    bool replaceLdFromLd(Instruction *ld, Record *ldRec);
2721    bool replaceLdFromSt(Instruction *ld, Record *stRec);
2722    bool replaceStFromSt(Instruction *restrict st, Record *stRec);
2723 
2724    void addRecord(Instruction *ldst);
2725    void purgeRecords(Instruction *const st, DataFile);
2726    void lockStores(Instruction *const ld);
2727    void reset();
2728 
2729 private:
2730    Record *prevRecord;
2731 };
2732 
MemoryOpt()2733 MemoryOpt::MemoryOpt() : recordPool(sizeof(MemoryOpt::Record), 6)
2734 {
2735    for (int i = 0; i < DATA_FILE_COUNT; ++i) {
2736       loads[i] = NULL;
2737       stores[i] = NULL;
2738    }
2739    prevRecord = NULL;
2740 }
2741 
2742 void
reset()2743 MemoryOpt::reset()
2744 {
2745    for (unsigned int i = 0; i < DATA_FILE_COUNT; ++i) {
2746       Record *it, *next;
2747       for (it = loads[i]; it; it = next) {
2748          next = it->next;
2749          recordPool.release(it);
2750       }
2751       loads[i] = NULL;
2752       for (it = stores[i]; it; it = next) {
2753          next = it->next;
2754          recordPool.release(it);
2755       }
2756       stores[i] = NULL;
2757    }
2758 }
2759 
2760 bool
combineLd(Record * rec,Instruction * ld)2761 MemoryOpt::combineLd(Record *rec, Instruction *ld)
2762 {
2763    int32_t offRc = rec->offset;
2764    int32_t offLd = ld->getSrc(0)->reg.data.offset;
2765    int sizeRc = rec->size;
2766    int sizeLd = typeSizeof(ld->dType);
2767    int size = sizeRc + sizeLd;
2768    int d, j;
2769 
2770    if (!prog->getTarget()->
2771        isAccessSupported(ld->getSrc(0)->reg.file, typeOfSize(size)))
2772       return false;
2773    // no unaligned loads
2774    if (((size == 0x8) && (MIN2(offLd, offRc) & 0x7)) ||
2775        ((size == 0xc) && (MIN2(offLd, offRc) & 0xf)))
2776       return false;
2777    // for compute indirect loads are not guaranteed to be aligned
2778    if (prog->getType() == Program::TYPE_COMPUTE && rec->rel[0])
2779       return false;
2780 
2781    assert(sizeRc + sizeLd <= 16 && offRc != offLd);
2782 
2783    // lock any stores that overlap with the load being merged into the
2784    // existing record.
2785    lockStores(ld);
2786 
2787    for (j = 0; sizeRc; sizeRc -= rec->insn->getDef(j)->reg.size, ++j);
2788 
2789    if (offLd < offRc) {
2790       int sz;
2791       for (sz = 0, d = 0; sz < sizeLd; sz += ld->getDef(d)->reg.size, ++d);
2792       // d: nr of definitions in ld
2793       // j: nr of definitions in rec->insn, move:
2794       for (d = d + j - 1; j > 0; --j, --d)
2795          rec->insn->setDef(d, rec->insn->getDef(j - 1));
2796 
2797       if (rec->insn->getSrc(0)->refCount() > 1)
2798          rec->insn->setSrc(0, cloneShallow(func, rec->insn->getSrc(0)));
2799       rec->offset = rec->insn->getSrc(0)->reg.data.offset = offLd;
2800 
2801       d = 0;
2802    } else {
2803       d = j;
2804    }
2805    // move definitions of @ld to @rec->insn
2806    for (j = 0; sizeLd; ++j, ++d) {
2807       sizeLd -= ld->getDef(j)->reg.size;
2808       rec->insn->setDef(d, ld->getDef(j));
2809    }
2810 
2811    rec->size = size;
2812    rec->insn->getSrc(0)->reg.size = size;
2813    rec->insn->setType(typeOfSize(size));
2814 
2815    delete_Instruction(prog, ld);
2816 
2817    return true;
2818 }
2819 
2820 bool
combineSt(Record * rec,Instruction * st)2821 MemoryOpt::combineSt(Record *rec, Instruction *st)
2822 {
2823    int32_t offRc = rec->offset;
2824    int32_t offSt = st->getSrc(0)->reg.data.offset;
2825    int sizeRc = rec->size;
2826    int sizeSt = typeSizeof(st->dType);
2827    int s = sizeSt / 4;
2828    int size = sizeRc + sizeSt;
2829    int j, k;
2830    Value *src[4]; // no modifiers in ValueRef allowed for st
2831    Value *extra[3];
2832 
2833    if (!prog->getTarget()->
2834        isAccessSupported(st->getSrc(0)->reg.file, typeOfSize(size)))
2835       return false;
2836    // no unaligned stores
2837    if (size == 8 && MIN2(offRc, offSt) & 0x7)
2838       return false;
2839    // for compute indirect stores are not guaranteed to be aligned
2840    if (prog->getType() == Program::TYPE_COMPUTE && rec->rel[0])
2841       return false;
2842 
2843    // There's really no great place to put this in a generic manner. Seemingly
2844    // wide stores at 0x60 don't work in GS shaders on SM50+. Don't combine
2845    // those.
2846    if (prog->getTarget()->getChipset() >= NVISA_GM107_CHIPSET &&
2847        prog->getType() == Program::TYPE_GEOMETRY &&
2848        st->getSrc(0)->reg.file == FILE_SHADER_OUTPUT &&
2849        rec->rel[0] == NULL &&
2850        MIN2(offRc, offSt) == 0x60)
2851       return false;
2852 
2853    // remove any existing load/store records for the store being merged into
2854    // the existing record.
2855    purgeRecords(st, DATA_FILE_COUNT);
2856 
2857    st->takeExtraSources(0, extra); // save predicate and indirect address
2858 
2859    if (offRc < offSt) {
2860       // save values from @st
2861       for (s = 0; sizeSt; ++s) {
2862          sizeSt -= st->getSrc(s + 1)->reg.size;
2863          src[s] = st->getSrc(s + 1);
2864       }
2865       // set record's values as low sources of @st
2866       for (j = 1; sizeRc; ++j) {
2867          sizeRc -= rec->insn->getSrc(j)->reg.size;
2868          st->setSrc(j, rec->insn->getSrc(j));
2869       }
2870       // set saved values as high sources of @st
2871       for (k = j, j = 0; j < s; ++j)
2872          st->setSrc(k++, src[j]);
2873 
2874       updateLdStOffset(st, offRc, func);
2875    } else {
2876       for (j = 1; sizeSt; ++j)
2877          sizeSt -= st->getSrc(j)->reg.size;
2878       for (s = 1; sizeRc; ++j, ++s) {
2879          sizeRc -= rec->insn->getSrc(s)->reg.size;
2880          st->setSrc(j, rec->insn->getSrc(s));
2881       }
2882       rec->offset = offSt;
2883    }
2884    st->putExtraSources(0, extra); // restore pointer and predicate
2885 
2886    delete_Instruction(prog, rec->insn);
2887    rec->insn = st;
2888    rec->size = size;
2889    rec->insn->getSrc(0)->reg.size = size;
2890    rec->insn->setType(typeOfSize(size));
2891    return true;
2892 }
2893 
2894 void
set(const Instruction * ldst)2895 MemoryOpt::Record::set(const Instruction *ldst)
2896 {
2897    const Symbol *mem = ldst->getSrc(0)->asSym();
2898    fileIndex = mem->reg.fileIndex;
2899    rel[0] = ldst->getIndirect(0, 0);
2900    rel[1] = ldst->getIndirect(0, 1);
2901    offset = mem->reg.data.offset;
2902    base = mem->getBase();
2903    size = typeSizeof(ldst->sType);
2904 }
2905 
2906 void
link(Record ** list)2907 MemoryOpt::Record::link(Record **list)
2908 {
2909    next = *list;
2910    if (next)
2911       next->prev = this;
2912    prev = NULL;
2913    *list = this;
2914 }
2915 
2916 void
unlink(Record ** list)2917 MemoryOpt::Record::unlink(Record **list)
2918 {
2919    if (next)
2920       next->prev = prev;
2921    if (prev)
2922       prev->next = next;
2923    else
2924       *list = next;
2925 }
2926 
2927 MemoryOpt::Record **
getList(const Instruction * insn)2928 MemoryOpt::getList(const Instruction *insn)
2929 {
2930    if (insn->op == OP_LOAD || insn->op == OP_VFETCH)
2931       return &loads[insn->src(0).getFile()];
2932    return &stores[insn->src(0).getFile()];
2933 }
2934 
2935 void
addRecord(Instruction * i)2936 MemoryOpt::addRecord(Instruction *i)
2937 {
2938    Record **list = getList(i);
2939    Record *it = reinterpret_cast<Record *>(recordPool.allocate());
2940 
2941    it->link(list);
2942    it->set(i);
2943    it->insn = i;
2944    it->locked = false;
2945 }
2946 
2947 MemoryOpt::Record *
findRecord(const Instruction * insn,bool load,bool & isAdj) const2948 MemoryOpt::findRecord(const Instruction *insn, bool load, bool& isAdj) const
2949 {
2950    const Symbol *sym = insn->getSrc(0)->asSym();
2951    const int size = typeSizeof(insn->sType);
2952    Record *rec = NULL;
2953    Record *it = load ? loads[sym->reg.file] : stores[sym->reg.file];
2954 
2955    for (; it; it = it->next) {
2956       if (it->locked && insn->op != OP_LOAD && insn->op != OP_VFETCH)
2957          continue;
2958       if ((it->offset >> 4) != (sym->reg.data.offset >> 4) ||
2959           it->rel[0] != insn->getIndirect(0, 0) ||
2960           it->fileIndex != sym->reg.fileIndex ||
2961           it->rel[1] != insn->getIndirect(0, 1))
2962          continue;
2963 
2964       if (it->offset < sym->reg.data.offset) {
2965          if (it->offset + it->size >= sym->reg.data.offset) {
2966             isAdj = (it->offset + it->size == sym->reg.data.offset);
2967             if (!isAdj)
2968                return it;
2969             if (!(it->offset & 0x7))
2970                rec = it;
2971          }
2972       } else {
2973          isAdj = it->offset != sym->reg.data.offset;
2974          if (size <= it->size && !isAdj)
2975             return it;
2976          else
2977          if (!(sym->reg.data.offset & 0x7))
2978             if (it->offset - size <= sym->reg.data.offset)
2979                rec = it;
2980       }
2981    }
2982    return rec;
2983 }
2984 
2985 bool
replaceLdFromSt(Instruction * ld,Record * rec)2986 MemoryOpt::replaceLdFromSt(Instruction *ld, Record *rec)
2987 {
2988    Instruction *st = rec->insn;
2989    int32_t offSt = rec->offset;
2990    int32_t offLd = ld->getSrc(0)->reg.data.offset;
2991    int d, s;
2992 
2993    for (s = 1; offSt != offLd && st->srcExists(s); ++s)
2994       offSt += st->getSrc(s)->reg.size;
2995    if (offSt != offLd)
2996       return false;
2997 
2998    for (d = 0; ld->defExists(d) && st->srcExists(s); ++d, ++s) {
2999       if (ld->getDef(d)->reg.size != st->getSrc(s)->reg.size)
3000          return false;
3001       if (st->getSrc(s)->reg.file != FILE_GPR)
3002          return false;
3003       ld->def(d).replace(st->src(s), false);
3004    }
3005    ld->bb->remove(ld);
3006    return true;
3007 }
3008 
3009 bool
replaceLdFromLd(Instruction * ldE,Record * rec)3010 MemoryOpt::replaceLdFromLd(Instruction *ldE, Record *rec)
3011 {
3012    Instruction *ldR = rec->insn;
3013    int32_t offR = rec->offset;
3014    int32_t offE = ldE->getSrc(0)->reg.data.offset;
3015    int dR, dE;
3016 
3017    assert(offR <= offE);
3018    for (dR = 0; offR < offE && ldR->defExists(dR); ++dR)
3019       offR += ldR->getDef(dR)->reg.size;
3020    if (offR != offE)
3021       return false;
3022 
3023    for (dE = 0; ldE->defExists(dE) && ldR->defExists(dR); ++dE, ++dR) {
3024       if (ldE->getDef(dE)->reg.size != ldR->getDef(dR)->reg.size)
3025          return false;
3026       ldE->def(dE).replace(ldR->getDef(dR), false);
3027    }
3028 
3029    delete_Instruction(prog, ldE);
3030    return true;
3031 }
3032 
3033 bool
replaceStFromSt(Instruction * restrict st,Record * rec)3034 MemoryOpt::replaceStFromSt(Instruction *restrict st, Record *rec)
3035 {
3036    const Instruction *const ri = rec->insn;
3037    Value *extra[3];
3038 
3039    int32_t offS = st->getSrc(0)->reg.data.offset;
3040    int32_t offR = rec->offset;
3041    int32_t endS = offS + typeSizeof(st->dType);
3042    int32_t endR = offR + typeSizeof(ri->dType);
3043 
3044    rec->size = MAX2(endS, endR) - MIN2(offS, offR);
3045 
3046    st->takeExtraSources(0, extra);
3047 
3048    if (offR < offS) {
3049       Value *vals[10];
3050       int s, n;
3051       int k = 0;
3052       // get non-replaced sources of ri
3053       for (s = 1; offR < offS; offR += ri->getSrc(s)->reg.size, ++s)
3054          vals[k++] = ri->getSrc(s);
3055       n = s;
3056       // get replaced sources of st
3057       for (s = 1; st->srcExists(s); offS += st->getSrc(s)->reg.size, ++s)
3058          vals[k++] = st->getSrc(s);
3059       // skip replaced sources of ri
3060       for (s = n; offR < endS; offR += ri->getSrc(s)->reg.size, ++s);
3061       // get non-replaced sources after values covered by st
3062       for (; offR < endR; offR += ri->getSrc(s)->reg.size, ++s)
3063          vals[k++] = ri->getSrc(s);
3064       assert((unsigned int)k <= ARRAY_SIZE(vals));
3065       for (s = 0; s < k; ++s)
3066          st->setSrc(s + 1, vals[s]);
3067       st->setSrc(0, ri->getSrc(0));
3068    } else
3069    if (endR > endS) {
3070       int j, s;
3071       for (j = 1; offR < endS; offR += ri->getSrc(j++)->reg.size);
3072       for (s = 1; offS < endS; offS += st->getSrc(s++)->reg.size);
3073       for (; offR < endR; offR += ri->getSrc(j++)->reg.size)
3074          st->setSrc(s++, ri->getSrc(j));
3075    }
3076    st->putExtraSources(0, extra);
3077 
3078    delete_Instruction(prog, rec->insn);
3079 
3080    rec->insn = st;
3081    rec->offset = st->getSrc(0)->reg.data.offset;
3082 
3083    st->setType(typeOfSize(rec->size));
3084 
3085    return true;
3086 }
3087 
3088 bool
overlaps(const Instruction * ldst) const3089 MemoryOpt::Record::overlaps(const Instruction *ldst) const
3090 {
3091    Record that;
3092    that.set(ldst);
3093 
3094    // This assumes that images/buffers can't overlap. They can.
3095    // TODO: Plumb the restrict logic through, and only skip when it's a
3096    // restrict situation, or there can implicitly be no writes.
3097    if (this->fileIndex != that.fileIndex && this->rel[1] == that.rel[1])
3098       return false;
3099 
3100    if (this->rel[0] || that.rel[0])
3101       return this->base == that.base;
3102 
3103    return
3104       (this->offset < that.offset + that.size) &&
3105       (this->offset + this->size > that.offset);
3106 }
3107 
3108 // We must not eliminate stores that affect the result of @ld if
3109 // we find later stores to the same location, and we may no longer
3110 // merge them with later stores.
3111 // The stored value can, however, still be used to determine the value
3112 // returned by future loads.
3113 void
lockStores(Instruction * const ld)3114 MemoryOpt::lockStores(Instruction *const ld)
3115 {
3116    for (Record *r = stores[ld->src(0).getFile()]; r; r = r->next)
3117       if (!r->locked && r->overlaps(ld))
3118          r->locked = true;
3119 }
3120 
3121 // Prior loads from the location of @st are no longer valid.
3122 // Stores to the location of @st may no longer be used to derive
3123 // the value at it nor be coalesced into later stores.
3124 void
purgeRecords(Instruction * const st,DataFile f)3125 MemoryOpt::purgeRecords(Instruction *const st, DataFile f)
3126 {
3127    if (st)
3128       f = st->src(0).getFile();
3129 
3130    for (Record *r = loads[f]; r; r = r->next)
3131       if (!st || r->overlaps(st))
3132          r->unlink(&loads[f]);
3133 
3134    for (Record *r = stores[f]; r; r = r->next)
3135       if (!st || r->overlaps(st))
3136          r->unlink(&stores[f]);
3137 }
3138 
3139 bool
visit(BasicBlock * bb)3140 MemoryOpt::visit(BasicBlock *bb)
3141 {
3142    bool ret = runOpt(bb);
3143    // Run again, one pass won't combine 4 32 bit ld/st to a single 128 bit ld/st
3144    // where 96 bit memory operations are forbidden.
3145    if (ret)
3146       ret = runOpt(bb);
3147    return ret;
3148 }
3149 
3150 bool
runOpt(BasicBlock * bb)3151 MemoryOpt::runOpt(BasicBlock *bb)
3152 {
3153    Instruction *ldst, *next;
3154    Record *rec;
3155    bool isAdjacent = true;
3156 
3157    for (ldst = bb->getEntry(); ldst; ldst = next) {
3158       bool keep = true;
3159       bool isLoad = true;
3160       next = ldst->next;
3161 
3162       if (ldst->op == OP_LOAD || ldst->op == OP_VFETCH) {
3163          if (ldst->isDead()) {
3164             // might have been produced by earlier optimization
3165             delete_Instruction(prog, ldst);
3166             continue;
3167          }
3168       } else
3169       if (ldst->op == OP_STORE || ldst->op == OP_EXPORT) {
3170          if (typeSizeof(ldst->dType) == 4 &&
3171              ldst->src(1).getFile() == FILE_GPR &&
3172              ldst->getSrc(1)->getInsn()->op == OP_NOP) {
3173             delete_Instruction(prog, ldst);
3174             continue;
3175          }
3176          isLoad = false;
3177       } else {
3178          // TODO: maybe have all fixed ops act as barrier ?
3179          if (ldst->op == OP_CALL ||
3180              ldst->op == OP_BAR ||
3181              ldst->op == OP_MEMBAR) {
3182             purgeRecords(NULL, FILE_MEMORY_LOCAL);
3183             purgeRecords(NULL, FILE_MEMORY_GLOBAL);
3184             purgeRecords(NULL, FILE_MEMORY_SHARED);
3185             purgeRecords(NULL, FILE_SHADER_OUTPUT);
3186          } else
3187          if (ldst->op == OP_ATOM || ldst->op == OP_CCTL) {
3188             if (ldst->src(0).getFile() == FILE_MEMORY_GLOBAL) {
3189                purgeRecords(NULL, FILE_MEMORY_LOCAL);
3190                purgeRecords(NULL, FILE_MEMORY_GLOBAL);
3191                purgeRecords(NULL, FILE_MEMORY_SHARED);
3192             } else {
3193                purgeRecords(NULL, ldst->src(0).getFile());
3194             }
3195          } else
3196          if (ldst->op == OP_EMIT || ldst->op == OP_RESTART) {
3197             purgeRecords(NULL, FILE_SHADER_OUTPUT);
3198          }
3199          continue;
3200       }
3201       if (ldst->getPredicate()) // TODO: handle predicated ld/st
3202          continue;
3203       if (ldst->perPatch) // TODO: create separate per-patch lists
3204          continue;
3205 
3206       if (isLoad) {
3207          DataFile file = ldst->src(0).getFile();
3208 
3209          // if ld l[]/g[] look for previous store to eliminate the reload
3210          if (file == FILE_MEMORY_GLOBAL || file == FILE_MEMORY_LOCAL) {
3211             // TODO: shared memory ?
3212             rec = findRecord(ldst, false, isAdjacent);
3213             if (rec && !isAdjacent)
3214                keep = !replaceLdFromSt(ldst, rec);
3215          }
3216 
3217          // or look for ld from the same location and replace this one
3218          rec = keep ? findRecord(ldst, true, isAdjacent) : NULL;
3219          if (rec) {
3220             if (!isAdjacent)
3221                keep = !replaceLdFromLd(ldst, rec);
3222             else
3223                // or combine a previous load with this one
3224                keep = !combineLd(rec, ldst);
3225          }
3226          if (keep)
3227             lockStores(ldst);
3228       } else {
3229          rec = findRecord(ldst, false, isAdjacent);
3230          if (rec) {
3231             if (!isAdjacent)
3232                keep = !replaceStFromSt(ldst, rec);
3233             else
3234                keep = !combineSt(rec, ldst);
3235          }
3236          if (keep)
3237             purgeRecords(ldst, DATA_FILE_COUNT);
3238       }
3239       if (keep)
3240          addRecord(ldst);
3241    }
3242    reset();
3243 
3244    return true;
3245 }
3246 
3247 // =============================================================================
3248 
3249 // Turn control flow into predicated instructions (after register allocation !).
3250 // TODO:
3251 // Could move this to before register allocation on NVC0 and also handle nested
3252 // constructs.
3253 class FlatteningPass : public Pass
3254 {
3255 private:
3256    virtual bool visit(Function *);
3257    virtual bool visit(BasicBlock *);
3258 
3259    bool tryPredicateConditional(BasicBlock *);
3260    void predicateInstructions(BasicBlock *, Value *pred, CondCode cc);
3261    void tryPropagateBranch(BasicBlock *);
3262    inline bool isConstantCondition(Value *pred);
3263    inline bool mayPredicate(const Instruction *, const Value *pred) const;
3264    inline void removeFlow(Instruction *);
3265 
3266    uint8_t gpr_unit;
3267 };
3268 
3269 bool
isConstantCondition(Value * pred)3270 FlatteningPass::isConstantCondition(Value *pred)
3271 {
3272    Instruction *insn = pred->getUniqueInsn();
3273    assert(insn);
3274    if (insn->op != OP_SET || insn->srcExists(2))
3275       return false;
3276 
3277    for (int s = 0; s < 2 && insn->srcExists(s); ++s) {
3278       Instruction *ld = insn->getSrc(s)->getUniqueInsn();
3279       DataFile file;
3280       if (ld) {
3281          if (ld->op != OP_MOV && ld->op != OP_LOAD)
3282             return false;
3283          if (ld->src(0).isIndirect(0))
3284             return false;
3285          file = ld->src(0).getFile();
3286       } else {
3287          file = insn->src(s).getFile();
3288          // catch $r63 on NVC0 and $r63/$r127 on NV50. Unfortunately maxGPR is
3289          // in register "units", which can vary between targets.
3290          if (file == FILE_GPR) {
3291             Value *v = insn->getSrc(s);
3292             int bytes = v->reg.data.id * MIN2(v->reg.size, 4);
3293             int units = bytes >> gpr_unit;
3294             if (units > prog->maxGPR)
3295                file = FILE_IMMEDIATE;
3296          }
3297       }
3298       if (file != FILE_IMMEDIATE && file != FILE_MEMORY_CONST)
3299          return false;
3300    }
3301    return true;
3302 }
3303 
3304 void
removeFlow(Instruction * insn)3305 FlatteningPass::removeFlow(Instruction *insn)
3306 {
3307    FlowInstruction *term = insn ? insn->asFlow() : NULL;
3308    if (!term)
3309       return;
3310    Graph::Edge::Type ty = term->bb->cfg.outgoing().getType();
3311 
3312    if (term->op == OP_BRA) {
3313       // TODO: this might get more difficult when we get arbitrary BRAs
3314       if (ty == Graph::Edge::CROSS || ty == Graph::Edge::BACK)
3315          return;
3316    } else
3317    if (term->op != OP_JOIN)
3318       return;
3319 
3320    Value *pred = term->getPredicate();
3321 
3322    delete_Instruction(prog, term);
3323 
3324    if (pred && pred->refCount() == 0) {
3325       Instruction *pSet = pred->getUniqueInsn();
3326       pred->join->reg.data.id = -1; // deallocate
3327       if (pSet->isDead())
3328          delete_Instruction(prog, pSet);
3329    }
3330 }
3331 
3332 void
predicateInstructions(BasicBlock * bb,Value * pred,CondCode cc)3333 FlatteningPass::predicateInstructions(BasicBlock *bb, Value *pred, CondCode cc)
3334 {
3335    for (Instruction *i = bb->getEntry(); i; i = i->next) {
3336       if (i->isNop())
3337          continue;
3338       assert(!i->getPredicate());
3339       i->setPredicate(cc, pred);
3340    }
3341    removeFlow(bb->getExit());
3342 }
3343 
3344 bool
mayPredicate(const Instruction * insn,const Value * pred) const3345 FlatteningPass::mayPredicate(const Instruction *insn, const Value *pred) const
3346 {
3347    if (insn->isPseudo())
3348       return true;
3349    // TODO: calls where we don't know which registers are modified
3350 
3351    if (!prog->getTarget()->mayPredicate(insn, pred))
3352       return false;
3353    for (int d = 0; insn->defExists(d); ++d)
3354       if (insn->getDef(d)->equals(pred))
3355          return false;
3356    return true;
3357 }
3358 
3359 // If we jump to BRA/RET/EXIT, replace the jump with it.
3360 // NOTE: We do not update the CFG anymore here !
3361 //
3362 // TODO: Handle cases where we skip over a branch (maybe do that elsewhere ?):
3363 //  BB:0
3364 //   @p0 bra BB:2 -> @!p0 bra BB:3 iff (!) BB:2 immediately adjoins BB:1
3365 //  BB1:
3366 //   bra BB:3
3367 //  BB2:
3368 //   ...
3369 //  BB3:
3370 //   ...
3371 void
tryPropagateBranch(BasicBlock * bb)3372 FlatteningPass::tryPropagateBranch(BasicBlock *bb)
3373 {
3374    for (Instruction *i = bb->getExit(); i && i->op == OP_BRA; i = i->prev) {
3375       BasicBlock *bf = i->asFlow()->target.bb;
3376 
3377       if (bf->getInsnCount() != 1)
3378          continue;
3379 
3380       FlowInstruction *bra = i->asFlow();
3381       FlowInstruction *rep = bf->getExit()->asFlow();
3382 
3383       if (!rep || rep->getPredicate())
3384          continue;
3385       if (rep->op != OP_BRA &&
3386           rep->op != OP_JOIN &&
3387           rep->op != OP_EXIT)
3388          continue;
3389 
3390       // TODO: If there are multiple branches to @rep, only the first would
3391       // be replaced, so only remove them after this pass is done ?
3392       // Also, need to check all incident blocks for fall-through exits and
3393       // add the branch there.
3394       bra->op = rep->op;
3395       bra->target.bb = rep->target.bb;
3396       if (bf->cfg.incidentCount() == 1)
3397          bf->remove(rep);
3398    }
3399 }
3400 
3401 bool
visit(Function * fn)3402 FlatteningPass::visit(Function *fn)
3403 {
3404    gpr_unit = prog->getTarget()->getFileUnit(FILE_GPR);
3405 
3406    return true;
3407 }
3408 
3409 bool
visit(BasicBlock * bb)3410 FlatteningPass::visit(BasicBlock *bb)
3411 {
3412    if (tryPredicateConditional(bb))
3413       return true;
3414 
3415    // try to attach join to previous instruction
3416    if (prog->getTarget()->hasJoin) {
3417       Instruction *insn = bb->getExit();
3418       if (insn && insn->op == OP_JOIN && !insn->getPredicate()) {
3419          insn = insn->prev;
3420          if (insn && !insn->getPredicate() &&
3421              !insn->asFlow() &&
3422              insn->op != OP_DISCARD &&
3423              insn->op != OP_TEXBAR &&
3424              !isTextureOp(insn->op) && // probably just nve4
3425              !isSurfaceOp(insn->op) && // not confirmed
3426              insn->op != OP_LINTERP && // probably just nve4
3427              insn->op != OP_PINTERP && // probably just nve4
3428              ((insn->op != OP_LOAD && insn->op != OP_STORE && insn->op != OP_ATOM) ||
3429               (typeSizeof(insn->dType) <= 4 && !insn->src(0).isIndirect(0))) &&
3430              !insn->isNop()) {
3431             insn->join = 1;
3432             bb->remove(bb->getExit());
3433             return true;
3434          }
3435       }
3436    }
3437 
3438    tryPropagateBranch(bb);
3439 
3440    return true;
3441 }
3442 
3443 bool
tryPredicateConditional(BasicBlock * bb)3444 FlatteningPass::tryPredicateConditional(BasicBlock *bb)
3445 {
3446    BasicBlock *bL = NULL, *bR = NULL;
3447    unsigned int nL = 0, nR = 0, limit = 12;
3448    Instruction *insn;
3449    unsigned int mask;
3450 
3451    mask = bb->initiatesSimpleConditional();
3452    if (!mask)
3453       return false;
3454 
3455    assert(bb->getExit());
3456    Value *pred = bb->getExit()->getPredicate();
3457    assert(pred);
3458 
3459    if (isConstantCondition(pred))
3460       limit = 4;
3461 
3462    Graph::EdgeIterator ei = bb->cfg.outgoing();
3463 
3464    if (mask & 1) {
3465       bL = BasicBlock::get(ei.getNode());
3466       for (insn = bL->getEntry(); insn; insn = insn->next, ++nL)
3467          if (!mayPredicate(insn, pred))
3468             return false;
3469       if (nL > limit)
3470          return false; // too long, do a real branch
3471    }
3472    ei.next();
3473 
3474    if (mask & 2) {
3475       bR = BasicBlock::get(ei.getNode());
3476       for (insn = bR->getEntry(); insn; insn = insn->next, ++nR)
3477          if (!mayPredicate(insn, pred))
3478             return false;
3479       if (nR > limit)
3480          return false; // too long, do a real branch
3481    }
3482 
3483    if (bL)
3484       predicateInstructions(bL, pred, bb->getExit()->cc);
3485    if (bR)
3486       predicateInstructions(bR, pred, inverseCondCode(bb->getExit()->cc));
3487 
3488    if (bb->joinAt) {
3489       bb->remove(bb->joinAt);
3490       bb->joinAt = NULL;
3491    }
3492    removeFlow(bb->getExit()); // delete the branch/join at the fork point
3493 
3494    // remove potential join operations at the end of the conditional
3495    if (prog->getTarget()->joinAnterior) {
3496       bb = BasicBlock::get((bL ? bL : bR)->cfg.outgoing().getNode());
3497       if (bb->getEntry() && bb->getEntry()->op == OP_JOIN)
3498          removeFlow(bb->getEntry());
3499    }
3500 
3501    return true;
3502 }
3503 
3504 // =============================================================================
3505 
3506 // Fold Immediate into MAD; must be done after register allocation due to
3507 // constraint SDST == SSRC2
3508 // TODO:
3509 // Does NVC0+ have other situations where this pass makes sense?
3510 class PostRaLoadPropagation : public Pass
3511 {
3512 private:
3513    virtual bool visit(Instruction *);
3514 
3515    void handleMADforNV50(Instruction *);
3516    void handleMADforNVC0(Instruction *);
3517 };
3518 
3519 static bool
post_ra_dead(Instruction * i)3520 post_ra_dead(Instruction *i)
3521 {
3522    for (int d = 0; i->defExists(d); ++d)
3523       if (i->getDef(d)->refCount())
3524          return false;
3525    return true;
3526 }
3527 
3528 // Fold Immediate into MAD; must be done after register allocation due to
3529 // constraint SDST == SSRC2
3530 void
handleMADforNV50(Instruction * i)3531 PostRaLoadPropagation::handleMADforNV50(Instruction *i)
3532 {
3533    if (i->def(0).getFile() != FILE_GPR ||
3534        i->src(0).getFile() != FILE_GPR ||
3535        i->src(1).getFile() != FILE_GPR ||
3536        i->src(2).getFile() != FILE_GPR ||
3537        i->getDef(0)->reg.data.id != i->getSrc(2)->reg.data.id)
3538       return;
3539 
3540    if (i->getDef(0)->reg.data.id >= 64 ||
3541        i->getSrc(0)->reg.data.id >= 64)
3542       return;
3543 
3544    if (i->flagsSrc >= 0 && i->getSrc(i->flagsSrc)->reg.data.id != 0)
3545       return;
3546 
3547    if (i->getPredicate())
3548       return;
3549 
3550    Value *vtmp;
3551    Instruction *def = i->getSrc(1)->getInsn();
3552 
3553    if (def && def->op == OP_SPLIT && typeSizeof(def->sType) == 4)
3554       def = def->getSrc(0)->getInsn();
3555    if (def && def->op == OP_MOV && def->src(0).getFile() == FILE_IMMEDIATE) {
3556       vtmp = i->getSrc(1);
3557       if (isFloatType(i->sType)) {
3558          i->setSrc(1, def->getSrc(0));
3559       } else {
3560          ImmediateValue val;
3561          // getImmediate() has side-effects on the argument so this *shouldn't*
3562          // be folded into the assert()
3563          ASSERTED bool ret = def->src(0).getImmediate(val);
3564          assert(ret);
3565          if (i->getSrc(1)->reg.data.id & 1)
3566             val.reg.data.u32 >>= 16;
3567          val.reg.data.u32 &= 0xffff;
3568          i->setSrc(1, new_ImmediateValue(prog, val.reg.data.u32));
3569       }
3570 
3571       /* There's no post-RA dead code elimination, so do it here
3572        * XXX: if we add more code-removing post-RA passes, we might
3573        *      want to create a post-RA dead-code elim pass */
3574       if (post_ra_dead(vtmp->getInsn())) {
3575          Value *src = vtmp->getInsn()->getSrc(0);
3576          // Careful -- splits will have already been removed from the
3577          // functions. Don't double-delete.
3578          if (vtmp->getInsn()->bb)
3579             delete_Instruction(prog, vtmp->getInsn());
3580          if (src->getInsn() && post_ra_dead(src->getInsn()))
3581             delete_Instruction(prog, src->getInsn());
3582       }
3583    }
3584 }
3585 
3586 void
handleMADforNVC0(Instruction * i)3587 PostRaLoadPropagation::handleMADforNVC0(Instruction *i)
3588 {
3589    if (i->def(0).getFile() != FILE_GPR ||
3590        i->src(0).getFile() != FILE_GPR ||
3591        i->src(1).getFile() != FILE_GPR ||
3592        i->src(2).getFile() != FILE_GPR ||
3593        i->getDef(0)->reg.data.id != i->getSrc(2)->reg.data.id)
3594       return;
3595 
3596    // TODO: gm107 can also do this for S32, maybe other chipsets as well
3597    if (i->dType != TYPE_F32)
3598       return;
3599 
3600    if ((i->src(2).mod | Modifier(NV50_IR_MOD_NEG)) != Modifier(NV50_IR_MOD_NEG))
3601       return;
3602 
3603    ImmediateValue val;
3604    int s;
3605 
3606    if (i->src(0).getImmediate(val))
3607       s = 1;
3608    else if (i->src(1).getImmediate(val))
3609       s = 0;
3610    else
3611       return;
3612 
3613    if ((i->src(s).mod | Modifier(NV50_IR_MOD_NEG)) != Modifier(NV50_IR_MOD_NEG))
3614       return;
3615 
3616    if (s == 1)
3617       i->swapSources(0, 1);
3618 
3619    Instruction *imm = i->getSrc(1)->getInsn();
3620    i->setSrc(1, imm->getSrc(0));
3621    if (post_ra_dead(imm))
3622       delete_Instruction(prog, imm);
3623 }
3624 
3625 bool
visit(Instruction * i)3626 PostRaLoadPropagation::visit(Instruction *i)
3627 {
3628    switch (i->op) {
3629    case OP_FMA:
3630    case OP_MAD:
3631       if (prog->getTarget()->getChipset() < 0xc0)
3632          handleMADforNV50(i);
3633       else
3634          handleMADforNVC0(i);
3635       break;
3636    default:
3637       break;
3638    }
3639 
3640    return true;
3641 }
3642 
3643 // =============================================================================
3644 
3645 // Common subexpression elimination. Stupid O^2 implementation.
3646 class LocalCSE : public Pass
3647 {
3648 private:
3649    virtual bool visit(BasicBlock *);
3650 
3651    inline bool tryReplace(Instruction **, Instruction *);
3652 
3653    DLList ops[OP_LAST + 1];
3654 };
3655 
3656 class GlobalCSE : public Pass
3657 {
3658 private:
3659    virtual bool visit(BasicBlock *);
3660 };
3661 
3662 bool
isActionEqual(const Instruction * that) const3663 Instruction::isActionEqual(const Instruction *that) const
3664 {
3665    if (this->op != that->op ||
3666        this->dType != that->dType ||
3667        this->sType != that->sType)
3668       return false;
3669    if (this->cc != that->cc)
3670       return false;
3671 
3672    if (this->asTex()) {
3673       if (memcmp(&this->asTex()->tex,
3674                  &that->asTex()->tex,
3675                  sizeof(this->asTex()->tex)))
3676          return false;
3677    } else
3678    if (this->asCmp()) {
3679       if (this->asCmp()->setCond != that->asCmp()->setCond)
3680          return false;
3681    } else
3682    if (this->asFlow()) {
3683       return false;
3684    } else
3685    if (this->op == OP_PHI && this->bb != that->bb) {
3686       /* TODO: we could probably be a bit smarter here by following the
3687        * control flow, but honestly, it is quite painful to check */
3688       return false;
3689    } else {
3690       if (this->ipa != that->ipa ||
3691           this->lanes != that->lanes ||
3692           this->perPatch != that->perPatch)
3693          return false;
3694       if (this->postFactor != that->postFactor)
3695          return false;
3696    }
3697 
3698    if (this->subOp != that->subOp ||
3699        this->saturate != that->saturate ||
3700        this->rnd != that->rnd ||
3701        this->ftz != that->ftz ||
3702        this->dnz != that->dnz ||
3703        this->cache != that->cache ||
3704        this->mask != that->mask)
3705       return false;
3706 
3707    return true;
3708 }
3709 
3710 bool
isResultEqual(const Instruction * that) const3711 Instruction::isResultEqual(const Instruction *that) const
3712 {
3713    unsigned int d, s;
3714 
3715    // NOTE: location of discard only affects tex with liveOnly and quadops
3716    if (!this->defExists(0) && this->op != OP_DISCARD)
3717       return false;
3718 
3719    if (!isActionEqual(that))
3720       return false;
3721 
3722    if (this->predSrc != that->predSrc)
3723       return false;
3724 
3725    for (d = 0; this->defExists(d); ++d) {
3726       if (!that->defExists(d) ||
3727           !this->getDef(d)->equals(that->getDef(d), false))
3728          return false;
3729    }
3730    if (that->defExists(d))
3731       return false;
3732 
3733    for (s = 0; this->srcExists(s); ++s) {
3734       if (!that->srcExists(s))
3735          return false;
3736       if (this->src(s).mod != that->src(s).mod)
3737          return false;
3738       if (!this->getSrc(s)->equals(that->getSrc(s), true))
3739          return false;
3740    }
3741    if (that->srcExists(s))
3742       return false;
3743 
3744    if (op == OP_LOAD || op == OP_VFETCH || op == OP_ATOM) {
3745       switch (src(0).getFile()) {
3746       case FILE_MEMORY_CONST:
3747       case FILE_SHADER_INPUT:
3748          return true;
3749       case FILE_SHADER_OUTPUT:
3750          return bb->getProgram()->getType() == Program::TYPE_TESSELLATION_EVAL;
3751       default:
3752          return false;
3753       }
3754    }
3755 
3756    return true;
3757 }
3758 
3759 // pull through common expressions from different in-blocks
3760 bool
visit(BasicBlock * bb)3761 GlobalCSE::visit(BasicBlock *bb)
3762 {
3763    Instruction *phi, *next, *ik;
3764    int s;
3765 
3766    // TODO: maybe do this with OP_UNION, too
3767 
3768    for (phi = bb->getPhi(); phi && phi->op == OP_PHI; phi = next) {
3769       next = phi->next;
3770       if (phi->getSrc(0)->refCount() > 1)
3771          continue;
3772       ik = phi->getSrc(0)->getInsn();
3773       if (!ik)
3774          continue; // probably a function input
3775       if (ik->defCount(0xff) > 1)
3776          continue; // too painful to check if we can really push this forward
3777       for (s = 1; phi->srcExists(s); ++s) {
3778          if (phi->getSrc(s)->refCount() > 1)
3779             break;
3780          if (!phi->getSrc(s)->getInsn() ||
3781              !phi->getSrc(s)->getInsn()->isResultEqual(ik))
3782             break;
3783       }
3784       if (!phi->srcExists(s)) {
3785          assert(ik->op != OP_PHI);
3786          Instruction *entry = bb->getEntry();
3787          ik->bb->remove(ik);
3788          if (!entry || entry->op != OP_JOIN)
3789             bb->insertHead(ik);
3790          else
3791             bb->insertAfter(entry, ik);
3792          ik->setDef(0, phi->getDef(0));
3793          delete_Instruction(prog, phi);
3794       }
3795    }
3796 
3797    return true;
3798 }
3799 
3800 bool
tryReplace(Instruction ** ptr,Instruction * i)3801 LocalCSE::tryReplace(Instruction **ptr, Instruction *i)
3802 {
3803    Instruction *old = *ptr;
3804 
3805    // TODO: maybe relax this later (causes trouble with OP_UNION)
3806    if (i->isPredicated())
3807       return false;
3808 
3809    if (!old->isResultEqual(i))
3810       return false;
3811 
3812    for (int d = 0; old->defExists(d); ++d)
3813       old->def(d).replace(i->getDef(d), false);
3814    delete_Instruction(prog, old);
3815    *ptr = NULL;
3816    return true;
3817 }
3818 
3819 bool
visit(BasicBlock * bb)3820 LocalCSE::visit(BasicBlock *bb)
3821 {
3822    unsigned int replaced;
3823 
3824    do {
3825       Instruction *ir, *next;
3826 
3827       replaced = 0;
3828 
3829       // will need to know the order of instructions
3830       int serial = 0;
3831       for (ir = bb->getFirst(); ir; ir = ir->next)
3832          ir->serial = serial++;
3833 
3834       for (ir = bb->getFirst(); ir; ir = next) {
3835          int s;
3836          Value *src = NULL;
3837 
3838          next = ir->next;
3839 
3840          if (ir->fixed) {
3841             ops[ir->op].insert(ir);
3842             continue;
3843          }
3844 
3845          for (s = 0; ir->srcExists(s); ++s)
3846             if (ir->getSrc(s)->asLValue())
3847                if (!src || ir->getSrc(s)->refCount() < src->refCount())
3848                   src = ir->getSrc(s);
3849 
3850          if (src) {
3851             for (Value::UseIterator it = src->uses.begin();
3852                  it != src->uses.end(); ++it) {
3853                Instruction *ik = (*it)->getInsn();
3854                if (ik && ik->bb == ir->bb && ik->serial < ir->serial)
3855                   if (tryReplace(&ir, ik))
3856                      break;
3857             }
3858          } else {
3859             DLLIST_FOR_EACH(&ops[ir->op], iter)
3860             {
3861                Instruction *ik = reinterpret_cast<Instruction *>(iter.get());
3862                if (tryReplace(&ir, ik))
3863                   break;
3864             }
3865          }
3866 
3867          if (ir)
3868             ops[ir->op].insert(ir);
3869          else
3870             ++replaced;
3871       }
3872       for (unsigned int i = 0; i <= OP_LAST; ++i)
3873          ops[i].clear();
3874 
3875    } while (replaced);
3876 
3877    return true;
3878 }
3879 
3880 // =============================================================================
3881 
3882 // Remove computations of unused values.
3883 class DeadCodeElim : public Pass
3884 {
3885 public:
3886    bool buryAll(Program *);
3887 
3888 private:
3889    virtual bool visit(BasicBlock *);
3890 
3891    void checkSplitLoad(Instruction *ld); // for partially dead loads
3892 
3893    unsigned int deadCount;
3894 };
3895 
3896 bool
buryAll(Program * prog)3897 DeadCodeElim::buryAll(Program *prog)
3898 {
3899    do {
3900       deadCount = 0;
3901       if (!this->run(prog, false, false))
3902          return false;
3903    } while (deadCount);
3904 
3905    return true;
3906 }
3907 
3908 bool
visit(BasicBlock * bb)3909 DeadCodeElim::visit(BasicBlock *bb)
3910 {
3911    Instruction *prev;
3912 
3913    for (Instruction *i = bb->getExit(); i; i = prev) {
3914       prev = i->prev;
3915       if (i->isDead()) {
3916          ++deadCount;
3917          delete_Instruction(prog, i);
3918       } else
3919       if (i->defExists(1) &&
3920           i->subOp == 0 &&
3921           (i->op == OP_VFETCH || i->op == OP_LOAD)) {
3922          checkSplitLoad(i);
3923       } else
3924       if (i->defExists(0) && !i->getDef(0)->refCount()) {
3925          if (i->op == OP_ATOM ||
3926              i->op == OP_SUREDP ||
3927              i->op == OP_SUREDB) {
3928             i->setDef(0, NULL);
3929             if (i->op == OP_ATOM && i->subOp == NV50_IR_SUBOP_ATOM_EXCH) {
3930                i->cache = CACHE_CV;
3931                i->op = OP_STORE;
3932                i->subOp = 0;
3933             }
3934          } else if (i->op == OP_LOAD && i->subOp == NV50_IR_SUBOP_LOAD_LOCKED) {
3935             i->setDef(0, i->getDef(1));
3936             i->setDef(1, NULL);
3937          }
3938       }
3939    }
3940    return true;
3941 }
3942 
3943 // Each load can go into up to 4 destinations, any of which might potentially
3944 // be dead (i.e. a hole). These can always be split into 2 loads, independent
3945 // of where the holes are. We find the first contiguous region, put it into
3946 // the first load, and then put the second contiguous region into the second
3947 // load. There can be at most 2 contiguous regions.
3948 //
3949 // Note that there are some restrictions, for example it's not possible to do
3950 // a 64-bit load that's not 64-bit aligned, so such a load has to be split
3951 // up. Also hardware doesn't support 96-bit loads, so those also have to be
3952 // split into a 64-bit and 32-bit load.
3953 void
checkSplitLoad(Instruction * ld1)3954 DeadCodeElim::checkSplitLoad(Instruction *ld1)
3955 {
3956    Instruction *ld2 = NULL; // can get at most 2 loads
3957    Value *def1[4];
3958    Value *def2[4];
3959    int32_t addr1, addr2;
3960    int32_t size1, size2;
3961    int d, n1, n2;
3962    uint32_t mask = 0xffffffff;
3963 
3964    for (d = 0; ld1->defExists(d); ++d)
3965       if (!ld1->getDef(d)->refCount() && ld1->getDef(d)->reg.data.id < 0)
3966          mask &= ~(1 << d);
3967    if (mask == 0xffffffff)
3968       return;
3969 
3970    addr1 = ld1->getSrc(0)->reg.data.offset;
3971    n1 = n2 = 0;
3972    size1 = size2 = 0;
3973 
3974    // Compute address/width for first load
3975    for (d = 0; ld1->defExists(d); ++d) {
3976       if (mask & (1 << d)) {
3977          if (size1 && (addr1 & 0x7))
3978             break;
3979          def1[n1] = ld1->getDef(d);
3980          size1 += def1[n1++]->reg.size;
3981       } else
3982       if (!n1) {
3983          addr1 += ld1->getDef(d)->reg.size;
3984       } else {
3985          break;
3986       }
3987    }
3988 
3989    // Scale back the size of the first load until it can be loaded. This
3990    // typically happens for TYPE_B96 loads.
3991    while (n1 &&
3992           !prog->getTarget()->isAccessSupported(ld1->getSrc(0)->reg.file,
3993                                                 typeOfSize(size1))) {
3994       size1 -= def1[--n1]->reg.size;
3995       d--;
3996    }
3997 
3998    // Compute address/width for second load
3999    for (addr2 = addr1 + size1; ld1->defExists(d); ++d) {
4000       if (mask & (1 << d)) {
4001          assert(!size2 || !(addr2 & 0x7));
4002          def2[n2] = ld1->getDef(d);
4003          size2 += def2[n2++]->reg.size;
4004       } else if (!n2) {
4005          assert(!n2);
4006          addr2 += ld1->getDef(d)->reg.size;
4007       } else {
4008          break;
4009       }
4010    }
4011 
4012    // Make sure that we've processed all the values
4013    for (; ld1->defExists(d); ++d)
4014       assert(!(mask & (1 << d)));
4015 
4016    updateLdStOffset(ld1, addr1, func);
4017    ld1->setType(typeOfSize(size1));
4018    for (d = 0; d < 4; ++d)
4019       ld1->setDef(d, (d < n1) ? def1[d] : NULL);
4020 
4021    if (!n2)
4022       return;
4023 
4024    ld2 = cloneShallow(func, ld1);
4025    updateLdStOffset(ld2, addr2, func);
4026    ld2->setType(typeOfSize(size2));
4027    for (d = 0; d < 4; ++d)
4028       ld2->setDef(d, (d < n2) ? def2[d] : NULL);
4029 
4030    ld1->bb->insertAfter(ld1, ld2);
4031 }
4032 
4033 // =============================================================================
4034 
4035 #define RUN_PASS(l, n, f)                       \
4036    if (level >= (l)) {                          \
4037       if (dbgFlags & NV50_IR_DEBUG_VERBOSE)     \
4038          INFO("PEEPHOLE: %s\n", #n);            \
4039       n pass;                                   \
4040       if (!pass.f(this))                        \
4041          return false;                          \
4042    }
4043 
4044 bool
optimizeSSA(int level)4045 Program::optimizeSSA(int level)
4046 {
4047    RUN_PASS(1, DeadCodeElim, buryAll);
4048    RUN_PASS(1, CopyPropagation, run);
4049    RUN_PASS(1, MergeSplits, run);
4050    RUN_PASS(2, GlobalCSE, run);
4051    RUN_PASS(1, LocalCSE, run);
4052    RUN_PASS(2, AlgebraicOpt, run);
4053    RUN_PASS(2, ModifierFolding, run); // before load propagation -> less checks
4054    RUN_PASS(1, ConstantFolding, foldAll);
4055    RUN_PASS(0, Split64BitOpPreRA, run);
4056    RUN_PASS(2, LateAlgebraicOpt, run);
4057    RUN_PASS(1, LoadPropagation, run);
4058    RUN_PASS(1, IndirectPropagation, run);
4059    RUN_PASS(2, MemoryOpt, run);
4060    RUN_PASS(2, LocalCSE, run);
4061    RUN_PASS(0, DeadCodeElim, buryAll);
4062 
4063    return true;
4064 }
4065 
4066 bool
optimizePostRA(int level)4067 Program::optimizePostRA(int level)
4068 {
4069    RUN_PASS(2, FlatteningPass, run);
4070    RUN_PASS(2, PostRaLoadPropagation, run);
4071 
4072    return true;
4073 }
4074 
4075 }
4076