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1 // Copyright 2013 the V8 project authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 
5 #ifndef V8_ARM64_MACRO_ASSEMBLER_ARM64_H_
6 #define V8_ARM64_MACRO_ASSEMBLER_ARM64_H_
7 
8 #include <vector>
9 
10 #include "src/arm64/assembler-arm64.h"
11 #include "src/bailout-reason.h"
12 #include "src/base/bits.h"
13 #include "src/globals.h"
14 
15 // Simulator specific helpers.
16 #if USE_SIMULATOR
17   // TODO(all): If possible automatically prepend an indicator like
18   // UNIMPLEMENTED or LOCATION.
19   #define ASM_UNIMPLEMENTED(message)                                         \
20   __ Debug(message, __LINE__, NO_PARAM)
21   #define ASM_UNIMPLEMENTED_BREAK(message)                                   \
22   __ Debug(message, __LINE__,                                                \
23            FLAG_ignore_asm_unimplemented_break ? NO_PARAM : BREAK)
24   #define ASM_LOCATION(message)                                              \
25   __ Debug("LOCATION: " message, __LINE__, NO_PARAM)
26 #else
27   #define ASM_UNIMPLEMENTED(message)
28   #define ASM_UNIMPLEMENTED_BREAK(message)
29   #define ASM_LOCATION(message)
30 #endif
31 
32 
33 namespace v8 {
34 namespace internal {
35 
36 // Give alias names to registers for calling conventions.
37 // TODO(titzer): arm64 is a pain for aliasing; get rid of these macros
38 #define kReturnRegister0 x0
39 #define kReturnRegister1 x1
40 #define kJSFunctionRegister x1
41 #define kContextRegister cp
42 #define kInterpreterAccumulatorRegister x0
43 #define kInterpreterRegisterFileRegister x18
44 #define kInterpreterBytecodeOffsetRegister x19
45 #define kInterpreterBytecodeArrayRegister x20
46 #define kInterpreterDispatchTableRegister x21
47 #define kJavaScriptCallArgCountRegister x0
48 #define kJavaScriptCallNewTargetRegister x3
49 #define kRuntimeCallFunctionRegister x1
50 #define kRuntimeCallArgCountRegister x0
51 
52 #define LS_MACRO_LIST(V)                                      \
53   V(Ldrb, Register&, rt, LDRB_w)                              \
54   V(Strb, Register&, rt, STRB_w)                              \
55   V(Ldrsb, Register&, rt, rt.Is64Bits() ? LDRSB_x : LDRSB_w)  \
56   V(Ldrh, Register&, rt, LDRH_w)                              \
57   V(Strh, Register&, rt, STRH_w)                              \
58   V(Ldrsh, Register&, rt, rt.Is64Bits() ? LDRSH_x : LDRSH_w)  \
59   V(Ldr, CPURegister&, rt, LoadOpFor(rt))                     \
60   V(Str, CPURegister&, rt, StoreOpFor(rt))                    \
61   V(Ldrsw, Register&, rt, LDRSW_x)
62 
63 #define LSPAIR_MACRO_LIST(V)                             \
64   V(Ldp, CPURegister&, rt, rt2, LoadPairOpFor(rt, rt2))  \
65   V(Stp, CPURegister&, rt, rt2, StorePairOpFor(rt, rt2)) \
66   V(Ldpsw, CPURegister&, rt, rt2, LDPSW_x)
67 
68 
69 // ----------------------------------------------------------------------------
70 // Static helper functions
71 
72 // Generate a MemOperand for loading a field from an object.
73 inline MemOperand FieldMemOperand(Register object, int offset);
74 inline MemOperand UntagSmiFieldMemOperand(Register object, int offset);
75 
76 // Generate a MemOperand for loading a SMI from memory.
77 inline MemOperand UntagSmiMemOperand(Register object, int offset);
78 
79 
80 // ----------------------------------------------------------------------------
81 // MacroAssembler
82 
83 enum BranchType {
84   // Copies of architectural conditions.
85   // The associated conditions can be used in place of those, the code will
86   // take care of reinterpreting them with the correct type.
87   integer_eq = eq,
88   integer_ne = ne,
89   integer_hs = hs,
90   integer_lo = lo,
91   integer_mi = mi,
92   integer_pl = pl,
93   integer_vs = vs,
94   integer_vc = vc,
95   integer_hi = hi,
96   integer_ls = ls,
97   integer_ge = ge,
98   integer_lt = lt,
99   integer_gt = gt,
100   integer_le = le,
101   integer_al = al,
102   integer_nv = nv,
103 
104   // These two are *different* from the architectural codes al and nv.
105   // 'always' is used to generate unconditional branches.
106   // 'never' is used to not generate a branch (generally as the inverse
107   // branch type of 'always).
108   always, never,
109   // cbz and cbnz
110   reg_zero, reg_not_zero,
111   // tbz and tbnz
112   reg_bit_clear, reg_bit_set,
113 
114   // Aliases.
115   kBranchTypeFirstCondition = eq,
116   kBranchTypeLastCondition = nv,
117   kBranchTypeFirstUsingReg = reg_zero,
118   kBranchTypeFirstUsingBit = reg_bit_clear
119 };
120 
InvertBranchType(BranchType type)121 inline BranchType InvertBranchType(BranchType type) {
122   if (kBranchTypeFirstCondition <= type && type <= kBranchTypeLastCondition) {
123     return static_cast<BranchType>(
124         NegateCondition(static_cast<Condition>(type)));
125   } else {
126     return static_cast<BranchType>(type ^ 1);
127   }
128 }
129 
130 enum RememberedSetAction { EMIT_REMEMBERED_SET, OMIT_REMEMBERED_SET };
131 enum SmiCheck { INLINE_SMI_CHECK, OMIT_SMI_CHECK };
132 enum PointersToHereCheck {
133   kPointersToHereMaybeInteresting,
134   kPointersToHereAreAlwaysInteresting
135 };
136 enum LinkRegisterStatus { kLRHasNotBeenSaved, kLRHasBeenSaved };
137 enum TargetAddressStorageMode {
138   CAN_INLINE_TARGET_ADDRESS,
139   NEVER_INLINE_TARGET_ADDRESS
140 };
141 enum UntagMode { kNotSpeculativeUntag, kSpeculativeUntag };
142 enum ArrayHasHoles { kArrayCantHaveHoles, kArrayCanHaveHoles };
143 enum CopyHint { kCopyUnknown, kCopyShort, kCopyLong };
144 enum DiscardMoveMode { kDontDiscardForSameWReg, kDiscardForSameWReg };
145 enum SeqStringSetCharCheckIndexType { kIndexIsSmi, kIndexIsInteger32 };
146 
147 class MacroAssembler : public Assembler {
148  public:
149   MacroAssembler(Isolate* isolate, byte* buffer, unsigned buffer_size,
150                  CodeObjectRequired create_code_object);
151 
152   inline Handle<Object> CodeObject();
153 
154   // Instruction set functions ------------------------------------------------
155   // Logical macros.
156   inline void And(const Register& rd,
157                   const Register& rn,
158                   const Operand& operand);
159   inline void Ands(const Register& rd,
160                    const Register& rn,
161                    const Operand& operand);
162   inline void Bic(const Register& rd,
163                   const Register& rn,
164                   const Operand& operand);
165   inline void Bics(const Register& rd,
166                    const Register& rn,
167                    const Operand& operand);
168   inline void Orr(const Register& rd,
169                   const Register& rn,
170                   const Operand& operand);
171   inline void Orn(const Register& rd,
172                   const Register& rn,
173                   const Operand& operand);
174   inline void Eor(const Register& rd,
175                   const Register& rn,
176                   const Operand& operand);
177   inline void Eon(const Register& rd,
178                   const Register& rn,
179                   const Operand& operand);
180   inline void Tst(const Register& rn, const Operand& operand);
181   void LogicalMacro(const Register& rd,
182                     const Register& rn,
183                     const Operand& operand,
184                     LogicalOp op);
185 
186   // Add and sub macros.
187   inline void Add(const Register& rd,
188                   const Register& rn,
189                   const Operand& operand);
190   inline void Adds(const Register& rd,
191                    const Register& rn,
192                    const Operand& operand);
193   inline void Sub(const Register& rd,
194                   const Register& rn,
195                   const Operand& operand);
196   inline void Subs(const Register& rd,
197                    const Register& rn,
198                    const Operand& operand);
199   inline void Cmn(const Register& rn, const Operand& operand);
200   inline void Cmp(const Register& rn, const Operand& operand);
201   inline void Neg(const Register& rd,
202                   const Operand& operand);
203   inline void Negs(const Register& rd,
204                    const Operand& operand);
205 
206   void AddSubMacro(const Register& rd,
207                    const Register& rn,
208                    const Operand& operand,
209                    FlagsUpdate S,
210                    AddSubOp op);
211 
212   // Add/sub with carry macros.
213   inline void Adc(const Register& rd,
214                   const Register& rn,
215                   const Operand& operand);
216   inline void Adcs(const Register& rd,
217                    const Register& rn,
218                    const Operand& operand);
219   inline void Sbc(const Register& rd,
220                   const Register& rn,
221                   const Operand& operand);
222   inline void Sbcs(const Register& rd,
223                    const Register& rn,
224                    const Operand& operand);
225   inline void Ngc(const Register& rd,
226                   const Operand& operand);
227   inline void Ngcs(const Register& rd,
228                    const Operand& operand);
229   void AddSubWithCarryMacro(const Register& rd,
230                             const Register& rn,
231                             const Operand& operand,
232                             FlagsUpdate S,
233                             AddSubWithCarryOp op);
234 
235   // Move macros.
236   void Mov(const Register& rd,
237            const Operand& operand,
238            DiscardMoveMode discard_mode = kDontDiscardForSameWReg);
239   void Mov(const Register& rd, uint64_t imm);
240   inline void Mvn(const Register& rd, uint64_t imm);
241   void Mvn(const Register& rd, const Operand& operand);
242   static bool IsImmMovn(uint64_t imm, unsigned reg_size);
243   static bool IsImmMovz(uint64_t imm, unsigned reg_size);
244   static unsigned CountClearHalfWords(uint64_t imm, unsigned reg_size);
245 
246   // Try to move an immediate into the destination register in a single
247   // instruction. Returns true for success, and updates the contents of dst.
248   // Returns false, otherwise.
249   bool TryOneInstrMoveImmediate(const Register& dst, int64_t imm);
250 
251   // Move an immediate into register dst, and return an Operand object for use
252   // with a subsequent instruction that accepts a shift. The value moved into
253   // dst is not necessarily equal to imm; it may have had a shifting operation
254   // applied to it that will be subsequently undone by the shift applied in the
255   // Operand.
256   Operand MoveImmediateForShiftedOp(const Register& dst, int64_t imm);
257 
258   // Conditional macros.
259   inline void Ccmp(const Register& rn,
260                    const Operand& operand,
261                    StatusFlags nzcv,
262                    Condition cond);
263   inline void Ccmn(const Register& rn,
264                    const Operand& operand,
265                    StatusFlags nzcv,
266                    Condition cond);
267   void ConditionalCompareMacro(const Register& rn,
268                                const Operand& operand,
269                                StatusFlags nzcv,
270                                Condition cond,
271                                ConditionalCompareOp op);
272   void Csel(const Register& rd,
273             const Register& rn,
274             const Operand& operand,
275             Condition cond);
276 
277   // Load/store macros.
278 #define DECLARE_FUNCTION(FN, REGTYPE, REG, OP) \
279   inline void FN(const REGTYPE REG, const MemOperand& addr);
280   LS_MACRO_LIST(DECLARE_FUNCTION)
281 #undef DECLARE_FUNCTION
282 
283   void LoadStoreMacro(const CPURegister& rt,
284                       const MemOperand& addr,
285                       LoadStoreOp op);
286 
287 #define DECLARE_FUNCTION(FN, REGTYPE, REG, REG2, OP) \
288   inline void FN(const REGTYPE REG, const REGTYPE REG2, const MemOperand& addr);
289   LSPAIR_MACRO_LIST(DECLARE_FUNCTION)
290 #undef DECLARE_FUNCTION
291 
292   void LoadStorePairMacro(const CPURegister& rt, const CPURegister& rt2,
293                           const MemOperand& addr, LoadStorePairOp op);
294 
295   // V8-specific load/store helpers.
296   void Load(const Register& rt, const MemOperand& addr, Representation r);
297   void Store(const Register& rt, const MemOperand& addr, Representation r);
298 
299   enum AdrHint {
300     // The target must be within the immediate range of adr.
301     kAdrNear,
302     // The target may be outside of the immediate range of adr. Additional
303     // instructions may be emitted.
304     kAdrFar
305   };
306   void Adr(const Register& rd, Label* label, AdrHint = kAdrNear);
307 
308   // Remaining instructions are simple pass-through calls to the assembler.
309   inline void Asr(const Register& rd, const Register& rn, unsigned shift);
310   inline void Asr(const Register& rd, const Register& rn, const Register& rm);
311 
312   // Branch type inversion relies on these relations.
313   STATIC_ASSERT((reg_zero      == (reg_not_zero ^ 1)) &&
314                 (reg_bit_clear == (reg_bit_set ^ 1)) &&
315                 (always        == (never ^ 1)));
316 
317   void B(Label* label, BranchType type, Register reg = NoReg, int bit = -1);
318 
319   inline void B(Label* label);
320   inline void B(Condition cond, Label* label);
321   void B(Label* label, Condition cond);
322   inline void Bfi(const Register& rd,
323                   const Register& rn,
324                   unsigned lsb,
325                   unsigned width);
326   inline void Bfxil(const Register& rd,
327                     const Register& rn,
328                     unsigned lsb,
329                     unsigned width);
330   inline void Bind(Label* label);
331   inline void Bl(Label* label);
332   inline void Blr(const Register& xn);
333   inline void Br(const Register& xn);
334   inline void Brk(int code);
335   void Cbnz(const Register& rt, Label* label);
336   void Cbz(const Register& rt, Label* label);
337   inline void Cinc(const Register& rd, const Register& rn, Condition cond);
338   inline void Cinv(const Register& rd, const Register& rn, Condition cond);
339   inline void Cls(const Register& rd, const Register& rn);
340   inline void Clz(const Register& rd, const Register& rn);
341   inline void Cneg(const Register& rd, const Register& rn, Condition cond);
342   inline void CzeroX(const Register& rd, Condition cond);
343   inline void CmovX(const Register& rd, const Register& rn, Condition cond);
344   inline void Cset(const Register& rd, Condition cond);
345   inline void Csetm(const Register& rd, Condition cond);
346   inline void Csinc(const Register& rd,
347                     const Register& rn,
348                     const Register& rm,
349                     Condition cond);
350   inline void Csinv(const Register& rd,
351                     const Register& rn,
352                     const Register& rm,
353                     Condition cond);
354   inline void Csneg(const Register& rd,
355                     const Register& rn,
356                     const Register& rm,
357                     Condition cond);
358   inline void Dmb(BarrierDomain domain, BarrierType type);
359   inline void Dsb(BarrierDomain domain, BarrierType type);
360   inline void Debug(const char* message, uint32_t code, Instr params = BREAK);
361   inline void Extr(const Register& rd,
362                    const Register& rn,
363                    const Register& rm,
364                    unsigned lsb);
365   inline void Fabs(const FPRegister& fd, const FPRegister& fn);
366   inline void Fadd(const FPRegister& fd,
367                    const FPRegister& fn,
368                    const FPRegister& fm);
369   inline void Fccmp(const FPRegister& fn,
370                     const FPRegister& fm,
371                     StatusFlags nzcv,
372                     Condition cond);
373   inline void Fcmp(const FPRegister& fn, const FPRegister& fm);
374   inline void Fcmp(const FPRegister& fn, double value);
375   inline void Fcsel(const FPRegister& fd,
376                     const FPRegister& fn,
377                     const FPRegister& fm,
378                     Condition cond);
379   inline void Fcvt(const FPRegister& fd, const FPRegister& fn);
380   inline void Fcvtas(const Register& rd, const FPRegister& fn);
381   inline void Fcvtau(const Register& rd, const FPRegister& fn);
382   inline void Fcvtms(const Register& rd, const FPRegister& fn);
383   inline void Fcvtmu(const Register& rd, const FPRegister& fn);
384   inline void Fcvtns(const Register& rd, const FPRegister& fn);
385   inline void Fcvtnu(const Register& rd, const FPRegister& fn);
386   inline void Fcvtzs(const Register& rd, const FPRegister& fn);
387   inline void Fcvtzu(const Register& rd, const FPRegister& fn);
388   inline void Fdiv(const FPRegister& fd,
389                    const FPRegister& fn,
390                    const FPRegister& fm);
391   inline void Fmadd(const FPRegister& fd,
392                     const FPRegister& fn,
393                     const FPRegister& fm,
394                     const FPRegister& fa);
395   inline void Fmax(const FPRegister& fd,
396                    const FPRegister& fn,
397                    const FPRegister& fm);
398   inline void Fmaxnm(const FPRegister& fd,
399                      const FPRegister& fn,
400                      const FPRegister& fm);
401   inline void Fmin(const FPRegister& fd,
402                    const FPRegister& fn,
403                    const FPRegister& fm);
404   inline void Fminnm(const FPRegister& fd,
405                      const FPRegister& fn,
406                      const FPRegister& fm);
407   inline void Fmov(FPRegister fd, FPRegister fn);
408   inline void Fmov(FPRegister fd, Register rn);
409   // Provide explicit double and float interfaces for FP immediate moves, rather
410   // than relying on implicit C++ casts. This allows signalling NaNs to be
411   // preserved when the immediate matches the format of fd. Most systems convert
412   // signalling NaNs to quiet NaNs when converting between float and double.
413   inline void Fmov(FPRegister fd, double imm);
414   inline void Fmov(FPRegister fd, float imm);
415   // Provide a template to allow other types to be converted automatically.
416   template<typename T>
Fmov(FPRegister fd,T imm)417   void Fmov(FPRegister fd, T imm) {
418     DCHECK(allow_macro_instructions_);
419     Fmov(fd, static_cast<double>(imm));
420   }
421   inline void Fmov(Register rd, FPRegister fn);
422   inline void Fmsub(const FPRegister& fd,
423                     const FPRegister& fn,
424                     const FPRegister& fm,
425                     const FPRegister& fa);
426   inline void Fmul(const FPRegister& fd,
427                    const FPRegister& fn,
428                    const FPRegister& fm);
429   inline void Fneg(const FPRegister& fd, const FPRegister& fn);
430   inline void Fnmadd(const FPRegister& fd,
431                      const FPRegister& fn,
432                      const FPRegister& fm,
433                      const FPRegister& fa);
434   inline void Fnmsub(const FPRegister& fd,
435                      const FPRegister& fn,
436                      const FPRegister& fm,
437                      const FPRegister& fa);
438   inline void Frinta(const FPRegister& fd, const FPRegister& fn);
439   inline void Frintm(const FPRegister& fd, const FPRegister& fn);
440   inline void Frintn(const FPRegister& fd, const FPRegister& fn);
441   inline void Frintp(const FPRegister& fd, const FPRegister& fn);
442   inline void Frintz(const FPRegister& fd, const FPRegister& fn);
443   inline void Fsqrt(const FPRegister& fd, const FPRegister& fn);
444   inline void Fsub(const FPRegister& fd,
445                    const FPRegister& fn,
446                    const FPRegister& fm);
447   inline void Hint(SystemHint code);
448   inline void Hlt(int code);
449   inline void Isb();
450   inline void Ldnp(const CPURegister& rt,
451                    const CPURegister& rt2,
452                    const MemOperand& src);
453   // Load a literal from the inline constant pool.
454   inline void Ldr(const CPURegister& rt, const Immediate& imm);
455   // Helper function for double immediate.
456   inline void Ldr(const CPURegister& rt, double imm);
457   inline void Lsl(const Register& rd, const Register& rn, unsigned shift);
458   inline void Lsl(const Register& rd, const Register& rn, const Register& rm);
459   inline void Lsr(const Register& rd, const Register& rn, unsigned shift);
460   inline void Lsr(const Register& rd, const Register& rn, const Register& rm);
461   inline void Madd(const Register& rd,
462                    const Register& rn,
463                    const Register& rm,
464                    const Register& ra);
465   inline void Mneg(const Register& rd, const Register& rn, const Register& rm);
466   inline void Mov(const Register& rd, const Register& rm);
467   inline void Movk(const Register& rd, uint64_t imm, int shift = -1);
468   inline void Mrs(const Register& rt, SystemRegister sysreg);
469   inline void Msr(SystemRegister sysreg, const Register& rt);
470   inline void Msub(const Register& rd,
471                    const Register& rn,
472                    const Register& rm,
473                    const Register& ra);
474   inline void Mul(const Register& rd, const Register& rn, const Register& rm);
Nop()475   inline void Nop() { nop(); }
476   inline void Rbit(const Register& rd, const Register& rn);
477   inline void Ret(const Register& xn = lr);
478   inline void Rev(const Register& rd, const Register& rn);
479   inline void Rev16(const Register& rd, const Register& rn);
480   inline void Rev32(const Register& rd, const Register& rn);
481   inline void Ror(const Register& rd, const Register& rs, unsigned shift);
482   inline void Ror(const Register& rd, const Register& rn, const Register& rm);
483   inline void Sbfiz(const Register& rd,
484                     const Register& rn,
485                     unsigned lsb,
486                     unsigned width);
487   inline void Sbfx(const Register& rd,
488                    const Register& rn,
489                    unsigned lsb,
490                    unsigned width);
491   inline void Scvtf(const FPRegister& fd,
492                     const Register& rn,
493                     unsigned fbits = 0);
494   inline void Sdiv(const Register& rd, const Register& rn, const Register& rm);
495   inline void Smaddl(const Register& rd,
496                      const Register& rn,
497                      const Register& rm,
498                      const Register& ra);
499   inline void Smsubl(const Register& rd,
500                      const Register& rn,
501                      const Register& rm,
502                      const Register& ra);
503   inline void Smull(const Register& rd,
504                     const Register& rn,
505                     const Register& rm);
506   inline void Smulh(const Register& rd,
507                     const Register& rn,
508                     const Register& rm);
509   inline void Umull(const Register& rd, const Register& rn, const Register& rm);
510   inline void Stnp(const CPURegister& rt,
511                    const CPURegister& rt2,
512                    const MemOperand& dst);
513   inline void Sxtb(const Register& rd, const Register& rn);
514   inline void Sxth(const Register& rd, const Register& rn);
515   inline void Sxtw(const Register& rd, const Register& rn);
516   void Tbnz(const Register& rt, unsigned bit_pos, Label* label);
517   void Tbz(const Register& rt, unsigned bit_pos, Label* label);
518   inline void Ubfiz(const Register& rd,
519                     const Register& rn,
520                     unsigned lsb,
521                     unsigned width);
522   inline void Ubfx(const Register& rd,
523                    const Register& rn,
524                    unsigned lsb,
525                    unsigned width);
526   inline void Ucvtf(const FPRegister& fd,
527                     const Register& rn,
528                     unsigned fbits = 0);
529   inline void Udiv(const Register& rd, const Register& rn, const Register& rm);
530   inline void Umaddl(const Register& rd,
531                      const Register& rn,
532                      const Register& rm,
533                      const Register& ra);
534   inline void Umsubl(const Register& rd,
535                      const Register& rn,
536                      const Register& rm,
537                      const Register& ra);
538   inline void Uxtb(const Register& rd, const Register& rn);
539   inline void Uxth(const Register& rd, const Register& rn);
540   inline void Uxtw(const Register& rd, const Register& rn);
541 
542   // Pseudo-instructions ------------------------------------------------------
543 
544   // Compute rd = abs(rm).
545   // This function clobbers the condition flags. On output the overflow flag is
546   // set iff the negation overflowed.
547   //
548   // If rm is the minimum representable value, the result is not representable.
549   // Handlers for each case can be specified using the relevant labels.
550   void Abs(const Register& rd, const Register& rm,
551            Label * is_not_representable = NULL,
552            Label * is_representable = NULL);
553 
554   // Push or pop up to 4 registers of the same width to or from the stack,
555   // using the current stack pointer as set by SetStackPointer.
556   //
557   // If an argument register is 'NoReg', all further arguments are also assumed
558   // to be 'NoReg', and are thus not pushed or popped.
559   //
560   // Arguments are ordered such that "Push(a, b);" is functionally equivalent
561   // to "Push(a); Push(b);".
562   //
563   // It is valid to push the same register more than once, and there is no
564   // restriction on the order in which registers are specified.
565   //
566   // It is not valid to pop into the same register more than once in one
567   // operation, not even into the zero register.
568   //
569   // If the current stack pointer (as set by SetStackPointer) is csp, then it
570   // must be aligned to 16 bytes on entry and the total size of the specified
571   // registers must also be a multiple of 16 bytes.
572   //
573   // Even if the current stack pointer is not the system stack pointer (csp),
574   // Push (and derived methods) will still modify the system stack pointer in
575   // order to comply with ABI rules about accessing memory below the system
576   // stack pointer.
577   //
578   // Other than the registers passed into Pop, the stack pointer and (possibly)
579   // the system stack pointer, these methods do not modify any other registers.
580   void Push(const CPURegister& src0, const CPURegister& src1 = NoReg,
581             const CPURegister& src2 = NoReg, const CPURegister& src3 = NoReg);
582   void Push(const CPURegister& src0, const CPURegister& src1,
583             const CPURegister& src2, const CPURegister& src3,
584             const CPURegister& src4, const CPURegister& src5 = NoReg,
585             const CPURegister& src6 = NoReg, const CPURegister& src7 = NoReg);
586   void Pop(const CPURegister& dst0, const CPURegister& dst1 = NoReg,
587            const CPURegister& dst2 = NoReg, const CPURegister& dst3 = NoReg);
588   void Pop(const CPURegister& dst0, const CPURegister& dst1,
589            const CPURegister& dst2, const CPURegister& dst3,
590            const CPURegister& dst4, const CPURegister& dst5 = NoReg,
591            const CPURegister& dst6 = NoReg, const CPURegister& dst7 = NoReg);
592   void Push(const Register& src0, const FPRegister& src1);
593 
594   // Alternative forms of Push and Pop, taking a RegList or CPURegList that
595   // specifies the registers that are to be pushed or popped. Higher-numbered
596   // registers are associated with higher memory addresses (as in the A32 push
597   // and pop instructions).
598   //
599   // (Push|Pop)SizeRegList allow you to specify the register size as a
600   // parameter. Only kXRegSizeInBits, kWRegSizeInBits, kDRegSizeInBits and
601   // kSRegSizeInBits are supported.
602   //
603   // Otherwise, (Push|Pop)(CPU|X|W|D|S)RegList is preferred.
604   void PushCPURegList(CPURegList registers);
605   void PopCPURegList(CPURegList registers);
606 
607   inline void PushSizeRegList(RegList registers, unsigned reg_size,
608       CPURegister::RegisterType type = CPURegister::kRegister) {
609     PushCPURegList(CPURegList(type, reg_size, registers));
610   }
611   inline void PopSizeRegList(RegList registers, unsigned reg_size,
612       CPURegister::RegisterType type = CPURegister::kRegister) {
613     PopCPURegList(CPURegList(type, reg_size, registers));
614   }
PushXRegList(RegList regs)615   inline void PushXRegList(RegList regs) {
616     PushSizeRegList(regs, kXRegSizeInBits);
617   }
PopXRegList(RegList regs)618   inline void PopXRegList(RegList regs) {
619     PopSizeRegList(regs, kXRegSizeInBits);
620   }
PushWRegList(RegList regs)621   inline void PushWRegList(RegList regs) {
622     PushSizeRegList(regs, kWRegSizeInBits);
623   }
PopWRegList(RegList regs)624   inline void PopWRegList(RegList regs) {
625     PopSizeRegList(regs, kWRegSizeInBits);
626   }
PushDRegList(RegList regs)627   inline void PushDRegList(RegList regs) {
628     PushSizeRegList(regs, kDRegSizeInBits, CPURegister::kFPRegister);
629   }
PopDRegList(RegList regs)630   inline void PopDRegList(RegList regs) {
631     PopSizeRegList(regs, kDRegSizeInBits, CPURegister::kFPRegister);
632   }
PushSRegList(RegList regs)633   inline void PushSRegList(RegList regs) {
634     PushSizeRegList(regs, kSRegSizeInBits, CPURegister::kFPRegister);
635   }
PopSRegList(RegList regs)636   inline void PopSRegList(RegList regs) {
637     PopSizeRegList(regs, kSRegSizeInBits, CPURegister::kFPRegister);
638   }
639 
640   // Push the specified register 'count' times.
641   void PushMultipleTimes(CPURegister src, Register count);
642   void PushMultipleTimes(CPURegister src, int count);
643 
644   // This is a convenience method for pushing a single Handle<Object>.
645   inline void Push(Handle<Object> handle);
Push(Smi * smi)646   void Push(Smi* smi) { Push(Handle<Smi>(smi, isolate())); }
647 
648   // Aliases of Push and Pop, required for V8 compatibility.
push(Register src)649   inline void push(Register src) {
650     Push(src);
651   }
pop(Register dst)652   inline void pop(Register dst) {
653     Pop(dst);
654   }
655 
656   // Sometimes callers need to push or pop multiple registers in a way that is
657   // difficult to structure efficiently for fixed Push or Pop calls. This scope
658   // allows push requests to be queued up, then flushed at once. The
659   // MacroAssembler will try to generate the most efficient sequence required.
660   //
661   // Unlike the other Push and Pop macros, PushPopQueue can handle mixed sets of
662   // register sizes and types.
663   class PushPopQueue {
664    public:
PushPopQueue(MacroAssembler * masm)665     explicit PushPopQueue(MacroAssembler* masm) : masm_(masm), size_(0) { }
666 
~PushPopQueue()667     ~PushPopQueue() {
668       DCHECK(queued_.empty());
669     }
670 
Queue(const CPURegister & rt)671     void Queue(const CPURegister& rt) {
672       size_ += rt.SizeInBytes();
673       queued_.push_back(rt);
674     }
675 
676     enum PreambleDirective {
677       WITH_PREAMBLE,
678       SKIP_PREAMBLE
679     };
680     void PushQueued(PreambleDirective preamble_directive = WITH_PREAMBLE);
681     void PopQueued();
682 
683    private:
684     MacroAssembler* masm_;
685     int size_;
686     std::vector<CPURegister> queued_;
687   };
688 
689   // Poke 'src' onto the stack. The offset is in bytes.
690   //
691   // If the current stack pointer (according to StackPointer()) is csp, then
692   // csp must be aligned to 16 bytes.
693   void Poke(const CPURegister& src, const Operand& offset);
694 
695   // Peek at a value on the stack, and put it in 'dst'. The offset is in bytes.
696   //
697   // If the current stack pointer (according to StackPointer()) is csp, then
698   // csp must be aligned to 16 bytes.
699   void Peek(const CPURegister& dst, const Operand& offset);
700 
701   // Poke 'src1' and 'src2' onto the stack. The values written will be adjacent
702   // with 'src2' at a higher address than 'src1'. The offset is in bytes.
703   //
704   // If the current stack pointer (according to StackPointer()) is csp, then
705   // csp must be aligned to 16 bytes.
706   void PokePair(const CPURegister& src1, const CPURegister& src2, int offset);
707 
708   // Peek at two values on the stack, and put them in 'dst1' and 'dst2'. The
709   // values peeked will be adjacent, with the value in 'dst2' being from a
710   // higher address than 'dst1'. The offset is in bytes.
711   //
712   // If the current stack pointer (according to StackPointer()) is csp, then
713   // csp must be aligned to 16 bytes.
714   void PeekPair(const CPURegister& dst1, const CPURegister& dst2, int offset);
715 
716   // Claim or drop stack space without actually accessing memory.
717   //
718   // In debug mode, both of these will write invalid data into the claimed or
719   // dropped space.
720   //
721   // If the current stack pointer (according to StackPointer()) is csp, then it
722   // must be aligned to 16 bytes and the size claimed or dropped must be a
723   // multiple of 16 bytes.
724   //
725   // Note that unit_size must be specified in bytes. For variants which take a
726   // Register count, the unit size must be a power of two.
727   inline void Claim(int64_t count, uint64_t unit_size = kXRegSize);
728   inline void Claim(const Register& count,
729                     uint64_t unit_size = kXRegSize);
730   inline void Drop(int64_t count, uint64_t unit_size = kXRegSize);
731   inline void Drop(const Register& count,
732                    uint64_t unit_size = kXRegSize);
733 
734   // Variants of Claim and Drop, where the 'count' parameter is a SMI held in a
735   // register.
736   inline void ClaimBySMI(const Register& count_smi,
737                          uint64_t unit_size = kXRegSize);
738   inline void DropBySMI(const Register& count_smi,
739                         uint64_t unit_size = kXRegSize);
740 
741   // Compare a register with an operand, and branch to label depending on the
742   // condition. May corrupt the status flags.
743   inline void CompareAndBranch(const Register& lhs,
744                                const Operand& rhs,
745                                Condition cond,
746                                Label* label);
747 
748   // Test the bits of register defined by bit_pattern, and branch if ANY of
749   // those bits are set. May corrupt the status flags.
750   inline void TestAndBranchIfAnySet(const Register& reg,
751                                     const uint64_t bit_pattern,
752                                     Label* label);
753 
754   // Test the bits of register defined by bit_pattern, and branch if ALL of
755   // those bits are clear (ie. not set.) May corrupt the status flags.
756   inline void TestAndBranchIfAllClear(const Register& reg,
757                                       const uint64_t bit_pattern,
758                                       Label* label);
759 
760   // Insert one or more instructions into the instruction stream that encode
761   // some caller-defined data. The instructions used will be executable with no
762   // side effects.
763   inline void InlineData(uint64_t data);
764 
765   // Insert an instrumentation enable marker into the instruction stream.
766   inline void EnableInstrumentation();
767 
768   // Insert an instrumentation disable marker into the instruction stream.
769   inline void DisableInstrumentation();
770 
771   // Insert an instrumentation event marker into the instruction stream. These
772   // will be picked up by the instrumentation system to annotate an instruction
773   // profile. The argument marker_name must be a printable two character string;
774   // it will be encoded in the event marker.
775   inline void AnnotateInstrumentation(const char* marker_name);
776 
777   // If emit_debug_code() is true, emit a run-time check to ensure that
778   // StackPointer() does not point below the system stack pointer.
779   //
780   // Whilst it is architecturally legal for StackPointer() to point below csp,
781   // it can be evidence of a potential bug because the ABI forbids accesses
782   // below csp.
783   //
784   // If StackPointer() is the system stack pointer (csp), then csp will be
785   // dereferenced to cause the processor (or simulator) to abort if it is not
786   // properly aligned.
787   //
788   // If emit_debug_code() is false, this emits no code.
789   void AssertStackConsistency();
790 
791   // Preserve the callee-saved registers (as defined by AAPCS64).
792   //
793   // Higher-numbered registers are pushed before lower-numbered registers, and
794   // thus get higher addresses.
795   // Floating-point registers are pushed before general-purpose registers, and
796   // thus get higher addresses.
797   //
798   // Note that registers are not checked for invalid values. Use this method
799   // only if you know that the GC won't try to examine the values on the stack.
800   //
801   // This method must not be called unless the current stack pointer (as set by
802   // SetStackPointer) is the system stack pointer (csp), and is aligned to
803   // ActivationFrameAlignment().
804   void PushCalleeSavedRegisters();
805 
806   // Restore the callee-saved registers (as defined by AAPCS64).
807   //
808   // Higher-numbered registers are popped after lower-numbered registers, and
809   // thus come from higher addresses.
810   // Floating-point registers are popped after general-purpose registers, and
811   // thus come from higher addresses.
812   //
813   // This method must not be called unless the current stack pointer (as set by
814   // SetStackPointer) is the system stack pointer (csp), and is aligned to
815   // ActivationFrameAlignment().
816   void PopCalleeSavedRegisters();
817 
818   // Set the current stack pointer, but don't generate any code.
SetStackPointer(const Register & stack_pointer)819   inline void SetStackPointer(const Register& stack_pointer) {
820     DCHECK(!TmpList()->IncludesAliasOf(stack_pointer));
821     sp_ = stack_pointer;
822   }
823 
824   // Return the current stack pointer, as set by SetStackPointer.
StackPointer()825   inline const Register& StackPointer() const {
826     return sp_;
827   }
828 
829   // Align csp for a frame, as per ActivationFrameAlignment, and make it the
830   // current stack pointer.
AlignAndSetCSPForFrame()831   inline void AlignAndSetCSPForFrame() {
832     int sp_alignment = ActivationFrameAlignment();
833     // AAPCS64 mandates at least 16-byte alignment.
834     DCHECK(sp_alignment >= 16);
835     DCHECK(base::bits::IsPowerOfTwo32(sp_alignment));
836     Bic(csp, StackPointer(), sp_alignment - 1);
837     SetStackPointer(csp);
838   }
839 
840   // Push the system stack pointer (csp) down to allow the same to be done to
841   // the current stack pointer (according to StackPointer()). This must be
842   // called _before_ accessing the memory.
843   //
844   // This is necessary when pushing or otherwise adding things to the stack, to
845   // satisfy the AAPCS64 constraint that the memory below the system stack
846   // pointer is not accessed.  The amount pushed will be increased as necessary
847   // to ensure csp remains aligned to 16 bytes.
848   //
849   // This method asserts that StackPointer() is not csp, since the call does
850   // not make sense in that context.
851   inline void BumpSystemStackPointer(const Operand& space);
852 
853   // Re-synchronizes the system stack pointer (csp) with the current stack
854   // pointer (according to StackPointer()).
855   //
856   // This method asserts that StackPointer() is not csp, since the call does
857   // not make sense in that context.
858   inline void SyncSystemStackPointer();
859 
860   // Helpers ------------------------------------------------------------------
861   // Root register.
862   inline void InitializeRootRegister();
863 
864   void AssertFPCRState(Register fpcr = NoReg);
865   void ConfigureFPCR();
866   void CanonicalizeNaN(const FPRegister& dst, const FPRegister& src);
CanonicalizeNaN(const FPRegister & reg)867   void CanonicalizeNaN(const FPRegister& reg) {
868     CanonicalizeNaN(reg, reg);
869   }
870 
871   // Load an object from the root table.
872   void LoadRoot(CPURegister destination,
873                 Heap::RootListIndex index);
874   // Store an object to the root table.
875   void StoreRoot(Register source,
876                  Heap::RootListIndex index);
877 
878   // Load both TrueValue and FalseValue roots.
879   void LoadTrueFalseRoots(Register true_root, Register false_root);
880 
881   void LoadHeapObject(Register dst, Handle<HeapObject> object);
882 
LoadObject(Register result,Handle<Object> object)883   void LoadObject(Register result, Handle<Object> object) {
884     AllowDeferredHandleDereference heap_object_check;
885     if (object->IsHeapObject()) {
886       LoadHeapObject(result, Handle<HeapObject>::cast(object));
887     } else {
888       DCHECK(object->IsSmi());
889       Mov(result, Operand(object));
890     }
891   }
892 
893   static int SafepointRegisterStackIndex(int reg_code);
894 
895   // This is required for compatibility with architecture independant code.
896   // Remove if not needed.
Move(Register dst,Register src)897   inline void Move(Register dst, Register src) { Mov(dst, src); }
Move(Register dst,Smi * src)898   inline void Move(Register dst, Smi* src) { Mov(dst, src); }
899 
900   void LoadInstanceDescriptors(Register map,
901                                Register descriptors);
902   void EnumLengthUntagged(Register dst, Register map);
903   void EnumLengthSmi(Register dst, Register map);
904   void NumberOfOwnDescriptors(Register dst, Register map);
905   void LoadAccessor(Register dst, Register holder, int accessor_index,
906                     AccessorComponent accessor);
907 
908   template<typename Field>
DecodeField(Register dst,Register src)909   void DecodeField(Register dst, Register src) {
910     static const int shift = Field::kShift;
911     static const int setbits = CountSetBits(Field::kMask, 32);
912     Ubfx(dst, src, shift, setbits);
913   }
914 
915   template<typename Field>
DecodeField(Register reg)916   void DecodeField(Register reg) {
917     DecodeField<Field>(reg, reg);
918   }
919 
920   // ---- SMI and Number Utilities ----
921 
922   inline void SmiTag(Register dst, Register src);
923   inline void SmiTag(Register smi);
924   inline void SmiUntag(Register dst, Register src);
925   inline void SmiUntag(Register smi);
926   inline void SmiUntagToDouble(FPRegister dst,
927                                Register src,
928                                UntagMode mode = kNotSpeculativeUntag);
929   inline void SmiUntagToFloat(FPRegister dst,
930                               Register src,
931                               UntagMode mode = kNotSpeculativeUntag);
932 
933   // Tag and push in one step.
934   inline void SmiTagAndPush(Register src);
935   inline void SmiTagAndPush(Register src1, Register src2);
936 
937   inline void JumpIfSmi(Register value,
938                         Label* smi_label,
939                         Label* not_smi_label = NULL);
940   inline void JumpIfNotSmi(Register value, Label* not_smi_label);
941   inline void JumpIfBothSmi(Register value1,
942                             Register value2,
943                             Label* both_smi_label,
944                             Label* not_smi_label = NULL);
945   inline void JumpIfEitherSmi(Register value1,
946                               Register value2,
947                               Label* either_smi_label,
948                               Label* not_smi_label = NULL);
949   inline void JumpIfEitherNotSmi(Register value1,
950                                  Register value2,
951                                  Label* not_smi_label);
952   inline void JumpIfBothNotSmi(Register value1,
953                                Register value2,
954                                Label* not_smi_label);
955 
956   // Abort execution if argument is a smi, enabled via --debug-code.
957   void AssertNotSmi(Register object, BailoutReason reason = kOperandIsASmi);
958   void AssertSmi(Register object, BailoutReason reason = kOperandIsNotASmi);
959 
960   inline void ObjectTag(Register tagged_obj, Register obj);
961   inline void ObjectUntag(Register untagged_obj, Register obj);
962 
963   // Abort execution if argument is not a name, enabled via --debug-code.
964   void AssertName(Register object);
965 
966   // Abort execution if argument is not a JSFunction, enabled via --debug-code.
967   void AssertFunction(Register object);
968 
969   // Abort execution if argument is not a JSBoundFunction,
970   // enabled via --debug-code.
971   void AssertBoundFunction(Register object);
972 
973   // Abort execution if argument is not undefined or an AllocationSite, enabled
974   // via --debug-code.
975   void AssertUndefinedOrAllocationSite(Register object, Register scratch);
976 
977   // Abort execution if argument is not a string, enabled via --debug-code.
978   void AssertString(Register object);
979 
980   // Abort execution if argument is not a positive or zero integer, enabled via
981   // --debug-code.
982   void AssertPositiveOrZero(Register value);
983 
984   void JumpIfHeapNumber(Register object, Label* on_heap_number,
985                         SmiCheckType smi_check_type = DONT_DO_SMI_CHECK);
986   void JumpIfNotHeapNumber(Register object, Label* on_not_heap_number,
987                            SmiCheckType smi_check_type = DONT_DO_SMI_CHECK);
988 
989   // Sets the vs flag if the input is -0.0.
990   void TestForMinusZero(DoubleRegister input);
991 
992   // Jump to label if the input double register contains -0.0.
993   void JumpIfMinusZero(DoubleRegister input, Label* on_negative_zero);
994 
995   // Jump to label if the input integer register contains the double precision
996   // floating point representation of -0.0.
997   void JumpIfMinusZero(Register input, Label* on_negative_zero);
998 
999   // Saturate a signed 32-bit integer in input to an unsigned 8-bit integer in
1000   // output.
1001   void ClampInt32ToUint8(Register in_out);
1002   void ClampInt32ToUint8(Register output, Register input);
1003 
1004   // Saturate a double in input to an unsigned 8-bit integer in output.
1005   void ClampDoubleToUint8(Register output,
1006                           DoubleRegister input,
1007                           DoubleRegister dbl_scratch);
1008 
1009   // Try to represent a double as a signed 32-bit int.
1010   // This succeeds if the result compares equal to the input, so inputs of -0.0
1011   // are represented as 0 and handled as a success.
1012   //
1013   // On output the Z flag is set if the operation was successful.
1014   void TryRepresentDoubleAsInt32(Register as_int,
1015                                  FPRegister value,
1016                                  FPRegister scratch_d,
1017                                  Label* on_successful_conversion = NULL,
1018                                  Label* on_failed_conversion = NULL) {
1019     DCHECK(as_int.Is32Bits());
1020     TryRepresentDoubleAsInt(as_int, value, scratch_d, on_successful_conversion,
1021                             on_failed_conversion);
1022   }
1023 
1024   // Try to represent a double as a signed 64-bit int.
1025   // This succeeds if the result compares equal to the input, so inputs of -0.0
1026   // are represented as 0 and handled as a success.
1027   //
1028   // On output the Z flag is set if the operation was successful.
1029   void TryRepresentDoubleAsInt64(Register as_int,
1030                                  FPRegister value,
1031                                  FPRegister scratch_d,
1032                                  Label* on_successful_conversion = NULL,
1033                                  Label* on_failed_conversion = NULL) {
1034     DCHECK(as_int.Is64Bits());
1035     TryRepresentDoubleAsInt(as_int, value, scratch_d, on_successful_conversion,
1036                             on_failed_conversion);
1037   }
1038 
1039   // ---- Object Utilities ----
1040 
1041   // Initialize fields with filler values.  Fields starting at |current_address|
1042   // not including |end_address| are overwritten with the value in |filler|.  At
1043   // the end the loop, |current_address| takes the value of |end_address|.
1044   void InitializeFieldsWithFiller(Register current_address,
1045                                   Register end_address, Register filler);
1046 
1047   // Copies a number of bytes from src to dst. All passed registers are
1048   // clobbered. On exit src and dst will point to the place just after where the
1049   // last byte was read or written and length will be zero. Hint may be used to
1050   // determine which is the most efficient algorithm to use for copying.
1051   void CopyBytes(Register dst,
1052                  Register src,
1053                  Register length,
1054                  Register scratch,
1055                  CopyHint hint = kCopyUnknown);
1056 
1057   // ---- String Utilities ----
1058 
1059 
1060   // Jump to label if either object is not a sequential one-byte string.
1061   // Optionally perform a smi check on the objects first.
1062   void JumpIfEitherIsNotSequentialOneByteStrings(
1063       Register first, Register second, Register scratch1, Register scratch2,
1064       Label* failure, SmiCheckType smi_check = DO_SMI_CHECK);
1065 
1066   // Check if instance type is sequential one-byte string and jump to label if
1067   // it is not.
1068   void JumpIfInstanceTypeIsNotSequentialOneByte(Register type, Register scratch,
1069                                                 Label* failure);
1070 
1071   // Checks if both instance types are sequential one-byte strings and jumps to
1072   // label if either is not.
1073   void JumpIfEitherInstanceTypeIsNotSequentialOneByte(
1074       Register first_object_instance_type, Register second_object_instance_type,
1075       Register scratch1, Register scratch2, Label* failure);
1076 
1077   // Checks if both instance types are sequential one-byte strings and jumps to
1078   // label if either is not.
1079   void JumpIfBothInstanceTypesAreNotSequentialOneByte(
1080       Register first_object_instance_type, Register second_object_instance_type,
1081       Register scratch1, Register scratch2, Label* failure);
1082 
1083   void JumpIfNotUniqueNameInstanceType(Register type, Label* not_unique_name);
1084 
1085   // ---- Calling / Jumping helpers ----
1086 
1087   // This is required for compatibility in architecture indepenedant code.
jmp(Label * L)1088   inline void jmp(Label* L) { B(L); }
1089 
1090   void CallStub(CodeStub* stub, TypeFeedbackId ast_id = TypeFeedbackId::None());
1091   void TailCallStub(CodeStub* stub);
1092 
1093   void CallRuntime(const Runtime::Function* f,
1094                    int num_arguments,
1095                    SaveFPRegsMode save_doubles = kDontSaveFPRegs);
1096 
1097   // Convenience function: Same as above, but takes the fid instead.
1098   void CallRuntime(Runtime::FunctionId fid, int num_arguments,
1099                    SaveFPRegsMode save_doubles = kDontSaveFPRegs) {
1100     CallRuntime(Runtime::FunctionForId(fid), num_arguments, save_doubles);
1101   }
1102 
1103   // Convenience function: Same as above, but takes the fid instead.
1104   void CallRuntime(Runtime::FunctionId fid,
1105                    SaveFPRegsMode save_doubles = kDontSaveFPRegs) {
1106     const Runtime::Function* function = Runtime::FunctionForId(fid);
1107     CallRuntime(function, function->nargs, save_doubles);
1108   }
1109 
CallRuntimeSaveDoubles(Runtime::FunctionId fid)1110   void CallRuntimeSaveDoubles(Runtime::FunctionId fid) {
1111     const Runtime::Function* function = Runtime::FunctionForId(fid);
1112     CallRuntime(function, function->nargs, kSaveFPRegs);
1113   }
1114 
1115   void TailCallRuntime(Runtime::FunctionId fid);
1116 
1117   int ActivationFrameAlignment();
1118 
1119   // Calls a C function.
1120   // The called function is not allowed to trigger a
1121   // garbage collection, since that might move the code and invalidate the
1122   // return address (unless this is somehow accounted for by the called
1123   // function).
1124   void CallCFunction(ExternalReference function,
1125                      int num_reg_arguments);
1126   void CallCFunction(ExternalReference function,
1127                      int num_reg_arguments,
1128                      int num_double_arguments);
1129   void CallCFunction(Register function,
1130                      int num_reg_arguments,
1131                      int num_double_arguments);
1132 
1133   // Jump to a runtime routine.
1134   void JumpToExternalReference(const ExternalReference& builtin);
1135 
1136   // Convenience function: call an external reference.
1137   void CallExternalReference(const ExternalReference& ext,
1138                              int num_arguments);
1139 
1140 
1141   // Invoke specified builtin JavaScript function.
1142   void InvokeBuiltin(int native_context_index, InvokeFlag flag,
1143                      const CallWrapper& call_wrapper = NullCallWrapper());
1144 
1145   void Jump(Register target);
1146   void Jump(Address target, RelocInfo::Mode rmode, Condition cond = al);
1147   void Jump(Handle<Code> code, RelocInfo::Mode rmode, Condition cond = al);
1148   void Jump(intptr_t target, RelocInfo::Mode rmode, Condition cond = al);
1149 
1150   void Call(Register target);
1151   void Call(Label* target);
1152   void Call(Address target, RelocInfo::Mode rmode);
1153   void Call(Handle<Code> code,
1154             RelocInfo::Mode rmode = RelocInfo::CODE_TARGET,
1155             TypeFeedbackId ast_id = TypeFeedbackId::None());
1156 
1157   // For every Call variant, there is a matching CallSize function that returns
1158   // the size (in bytes) of the call sequence.
1159   static int CallSize(Register target);
1160   static int CallSize(Label* target);
1161   static int CallSize(Address target, RelocInfo::Mode rmode);
1162   static int CallSize(Handle<Code> code,
1163                       RelocInfo::Mode rmode = RelocInfo::CODE_TARGET,
1164                       TypeFeedbackId ast_id = TypeFeedbackId::None());
1165 
1166   // Registers used through the invocation chain are hard-coded.
1167   // We force passing the parameters to ensure the contracts are correctly
1168   // honoured by the caller.
1169   // 'function' must be x1.
1170   // 'actual' must use an immediate or x0.
1171   // 'expected' must use an immediate or x2.
1172   // 'call_kind' must be x5.
1173   void InvokePrologue(const ParameterCount& expected,
1174                       const ParameterCount& actual,
1175                       Label* done,
1176                       InvokeFlag flag,
1177                       bool* definitely_mismatches,
1178                       const CallWrapper& call_wrapper);
1179   void FloodFunctionIfStepping(Register fun, Register new_target,
1180                                const ParameterCount& expected,
1181                                const ParameterCount& actual);
1182   void InvokeFunctionCode(Register function, Register new_target,
1183                           const ParameterCount& expected,
1184                           const ParameterCount& actual, InvokeFlag flag,
1185                           const CallWrapper& call_wrapper);
1186   // Invoke the JavaScript function in the given register.
1187   // Changes the current context to the context in the function before invoking.
1188   void InvokeFunction(Register function,
1189                       Register new_target,
1190                       const ParameterCount& actual,
1191                       InvokeFlag flag,
1192                       const CallWrapper& call_wrapper);
1193   void InvokeFunction(Register function,
1194                       const ParameterCount& expected,
1195                       const ParameterCount& actual,
1196                       InvokeFlag flag,
1197                       const CallWrapper& call_wrapper);
1198   void InvokeFunction(Handle<JSFunction> function,
1199                       const ParameterCount& expected,
1200                       const ParameterCount& actual,
1201                       InvokeFlag flag,
1202                       const CallWrapper& call_wrapper);
1203 
1204 
1205   // ---- Floating point helpers ----
1206 
1207   // Perform a conversion from a double to a signed int64. If the input fits in
1208   // range of the 64-bit result, execution branches to done. Otherwise,
1209   // execution falls through, and the sign of the result can be used to
1210   // determine if overflow was towards positive or negative infinity.
1211   //
1212   // On successful conversion, the least significant 32 bits of the result are
1213   // equivalent to the ECMA-262 operation "ToInt32".
1214   //
1215   // Only public for the test code in test-code-stubs-arm64.cc.
1216   void TryConvertDoubleToInt64(Register result,
1217                                DoubleRegister input,
1218                                Label* done);
1219 
1220   // Performs a truncating conversion of a floating point number as used by
1221   // the JS bitwise operations. See ECMA-262 9.5: ToInt32.
1222   // Exits with 'result' holding the answer.
1223   void TruncateDoubleToI(Register result, DoubleRegister double_input);
1224 
1225   // Performs a truncating conversion of a heap number as used by
1226   // the JS bitwise operations. See ECMA-262 9.5: ToInt32. 'result' and 'input'
1227   // must be different registers.  Exits with 'result' holding the answer.
1228   void TruncateHeapNumberToI(Register result, Register object);
1229 
1230   // Converts the smi or heap number in object to an int32 using the rules
1231   // for ToInt32 as described in ECMAScript 9.5.: the value is truncated
1232   // and brought into the range -2^31 .. +2^31 - 1. 'result' and 'input' must be
1233   // different registers.
1234   void TruncateNumberToI(Register object,
1235                          Register result,
1236                          Register heap_number_map,
1237                          Label* not_int32);
1238 
1239   // ---- Code generation helpers ----
1240 
set_generating_stub(bool value)1241   void set_generating_stub(bool value) { generating_stub_ = value; }
generating_stub()1242   bool generating_stub() const { return generating_stub_; }
1243 #if DEBUG
set_allow_macro_instructions(bool value)1244   void set_allow_macro_instructions(bool value) {
1245     allow_macro_instructions_ = value;
1246   }
allow_macro_instructions()1247   bool allow_macro_instructions() const { return allow_macro_instructions_; }
1248 #endif
use_real_aborts()1249   bool use_real_aborts() const { return use_real_aborts_; }
set_has_frame(bool value)1250   void set_has_frame(bool value) { has_frame_ = value; }
has_frame()1251   bool has_frame() const { return has_frame_; }
1252   bool AllowThisStubCall(CodeStub* stub);
1253 
1254   class NoUseRealAbortsScope {
1255    public:
NoUseRealAbortsScope(MacroAssembler * masm)1256     explicit NoUseRealAbortsScope(MacroAssembler* masm) :
1257         saved_(masm->use_real_aborts_), masm_(masm) {
1258       masm_->use_real_aborts_ = false;
1259     }
~NoUseRealAbortsScope()1260     ~NoUseRealAbortsScope() {
1261       masm_->use_real_aborts_ = saved_;
1262     }
1263    private:
1264     bool saved_;
1265     MacroAssembler* masm_;
1266   };
1267 
1268   // ---------------------------------------------------------------------------
1269   // Debugger Support
1270 
1271   void DebugBreak();
1272 
1273   // ---------------------------------------------------------------------------
1274   // Exception handling
1275 
1276   // Push a new stack handler and link into stack handler chain.
1277   void PushStackHandler();
1278 
1279   // Unlink the stack handler on top of the stack from the stack handler chain.
1280   // Must preserve the result register.
1281   void PopStackHandler();
1282 
1283 
1284   // ---------------------------------------------------------------------------
1285   // Allocation support
1286 
1287   // Allocate an object in new space or old space. The object_size is
1288   // specified either in bytes or in words if the allocation flag SIZE_IN_WORDS
1289   // is passed. The allocated object is returned in result.
1290   //
1291   // If the new space is exhausted control continues at the gc_required label.
1292   // In this case, the result and scratch registers may still be clobbered.
1293   // If flags includes TAG_OBJECT, the result is tagged as as a heap object.
1294   void Allocate(Register object_size, Register result, Register result_end,
1295                 Register scratch, Label* gc_required, AllocationFlags flags);
1296 
1297   void Allocate(int object_size,
1298                 Register result,
1299                 Register scratch1,
1300                 Register scratch2,
1301                 Label* gc_required,
1302                 AllocationFlags flags);
1303 
1304   void AllocateTwoByteString(Register result,
1305                              Register length,
1306                              Register scratch1,
1307                              Register scratch2,
1308                              Register scratch3,
1309                              Label* gc_required);
1310   void AllocateOneByteString(Register result, Register length,
1311                              Register scratch1, Register scratch2,
1312                              Register scratch3, Label* gc_required);
1313   void AllocateTwoByteConsString(Register result,
1314                                  Register length,
1315                                  Register scratch1,
1316                                  Register scratch2,
1317                                  Label* gc_required);
1318   void AllocateOneByteConsString(Register result, Register length,
1319                                  Register scratch1, Register scratch2,
1320                                  Label* gc_required);
1321   void AllocateTwoByteSlicedString(Register result,
1322                                    Register length,
1323                                    Register scratch1,
1324                                    Register scratch2,
1325                                    Label* gc_required);
1326   void AllocateOneByteSlicedString(Register result, Register length,
1327                                    Register scratch1, Register scratch2,
1328                                    Label* gc_required);
1329 
1330   // Allocates a heap number or jumps to the gc_required label if the young
1331   // space is full and a scavenge is needed.
1332   // All registers are clobbered.
1333   // If no heap_number_map register is provided, the function will take care of
1334   // loading it.
1335   void AllocateHeapNumber(Register result,
1336                           Label* gc_required,
1337                           Register scratch1,
1338                           Register scratch2,
1339                           CPURegister value = NoFPReg,
1340                           CPURegister heap_number_map = NoReg,
1341                           MutableMode mode = IMMUTABLE);
1342 
1343   // Allocate and initialize a JSValue wrapper with the specified {constructor}
1344   // and {value}.
1345   void AllocateJSValue(Register result, Register constructor, Register value,
1346                        Register scratch1, Register scratch2,
1347                        Label* gc_required);
1348 
1349   // ---------------------------------------------------------------------------
1350   // Support functions.
1351 
1352   // Machine code version of Map::GetConstructor().
1353   // |temp| holds |result|'s map when done, and |temp2| its instance type.
1354   void GetMapConstructor(Register result, Register map, Register temp,
1355                          Register temp2);
1356 
1357   void TryGetFunctionPrototype(Register function, Register result,
1358                                Register scratch, Label* miss);
1359 
1360   // Compare object type for heap object.  heap_object contains a non-Smi
1361   // whose object type should be compared with the given type.  This both
1362   // sets the flags and leaves the object type in the type_reg register.
1363   // It leaves the map in the map register (unless the type_reg and map register
1364   // are the same register).  It leaves the heap object in the heap_object
1365   // register unless the heap_object register is the same register as one of the
1366   // other registers.
1367   void CompareObjectType(Register heap_object,
1368                          Register map,
1369                          Register type_reg,
1370                          InstanceType type);
1371 
1372 
1373   // Compare object type for heap object, and branch if equal (or not.)
1374   // heap_object contains a non-Smi whose object type should be compared with
1375   // the given type.  This both sets the flags and leaves the object type in
1376   // the type_reg register. It leaves the map in the map register (unless the
1377   // type_reg and map register are the same register).  It leaves the heap
1378   // object in the heap_object register unless the heap_object register is the
1379   // same register as one of the other registers.
1380   void JumpIfObjectType(Register object,
1381                         Register map,
1382                         Register type_reg,
1383                         InstanceType type,
1384                         Label* if_cond_pass,
1385                         Condition cond = eq);
1386 
1387   void JumpIfNotObjectType(Register object,
1388                            Register map,
1389                            Register type_reg,
1390                            InstanceType type,
1391                            Label* if_not_object);
1392 
1393   // Compare instance type in a map.  map contains a valid map object whose
1394   // object type should be compared with the given type.  This both
1395   // sets the flags and leaves the object type in the type_reg register.
1396   void CompareInstanceType(Register map,
1397                            Register type_reg,
1398                            InstanceType type);
1399 
1400   // Compare an object's map with the specified map. Condition flags are set
1401   // with result of map compare.
1402   void CompareObjectMap(Register obj, Heap::RootListIndex index);
1403 
1404   // Compare an object's map with the specified map. Condition flags are set
1405   // with result of map compare.
1406   void CompareObjectMap(Register obj, Register scratch, Handle<Map> map);
1407 
1408   // As above, but the map of the object is already loaded into the register
1409   // which is preserved by the code generated.
1410   void CompareMap(Register obj_map,
1411                   Handle<Map> map);
1412 
1413   // Check if the map of an object is equal to a specified map and branch to
1414   // label if not. Skip the smi check if not required (object is known to be a
1415   // heap object). If mode is ALLOW_ELEMENT_TRANSITION_MAPS, then also match
1416   // against maps that are ElementsKind transition maps of the specified map.
1417   void CheckMap(Register obj,
1418                 Register scratch,
1419                 Handle<Map> map,
1420                 Label* fail,
1421                 SmiCheckType smi_check_type);
1422 
1423 
1424   void CheckMap(Register obj,
1425                 Register scratch,
1426                 Heap::RootListIndex index,
1427                 Label* fail,
1428                 SmiCheckType smi_check_type);
1429 
1430   // As above, but the map of the object is already loaded into obj_map, and is
1431   // preserved.
1432   void CheckMap(Register obj_map,
1433                 Handle<Map> map,
1434                 Label* fail,
1435                 SmiCheckType smi_check_type);
1436 
1437   // Check if the map of an object is equal to a specified weak map and branch
1438   // to a specified target if equal. Skip the smi check if not required
1439   // (object is known to be a heap object)
1440   void DispatchWeakMap(Register obj, Register scratch1, Register scratch2,
1441                        Handle<WeakCell> cell, Handle<Code> success,
1442                        SmiCheckType smi_check_type);
1443 
1444   // Compare the given value and the value of weak cell.
1445   void CmpWeakValue(Register value, Handle<WeakCell> cell, Register scratch);
1446 
1447   void GetWeakValue(Register value, Handle<WeakCell> cell);
1448 
1449   // Load the value of the weak cell in the value register. Branch to the given
1450   // miss label if the weak cell was cleared.
1451   void LoadWeakValue(Register value, Handle<WeakCell> cell, Label* miss);
1452 
1453   // Test the bitfield of the heap object map with mask and set the condition
1454   // flags. The object register is preserved.
1455   void TestMapBitfield(Register object, uint64_t mask);
1456 
1457   // Load the elements kind field from a map, and return it in the result
1458   // register.
1459   void LoadElementsKindFromMap(Register result, Register map);
1460 
1461   // Load the value from the root list and push it onto the stack.
1462   void PushRoot(Heap::RootListIndex index);
1463 
1464   // Compare the object in a register to a value from the root list.
1465   void CompareRoot(const Register& obj, Heap::RootListIndex index);
1466 
1467   // Compare the object in a register to a value and jump if they are equal.
1468   void JumpIfRoot(const Register& obj,
1469                   Heap::RootListIndex index,
1470                   Label* if_equal);
1471 
1472   // Compare the object in a register to a value and jump if they are not equal.
1473   void JumpIfNotRoot(const Register& obj,
1474                      Heap::RootListIndex index,
1475                      Label* if_not_equal);
1476 
1477   // Load and check the instance type of an object for being a unique name.
1478   // Loads the type into the second argument register.
1479   // The object and type arguments can be the same register; in that case it
1480   // will be overwritten with the type.
1481   // Fall-through if the object was a string and jump on fail otherwise.
1482   inline void IsObjectNameType(Register object, Register type, Label* fail);
1483 
1484   // Load and check the instance type of an object for being a string.
1485   // Loads the type into the second argument register.
1486   // The object and type arguments can be the same register; in that case it
1487   // will be overwritten with the type.
1488   // Jumps to not_string or string appropriate. If the appropriate label is
1489   // NULL, fall through.
1490   inline void IsObjectJSStringType(Register object, Register type,
1491                                    Label* not_string, Label* string = NULL);
1492 
1493   // Compare the contents of a register with an operand, and branch to true,
1494   // false or fall through, depending on condition.
1495   void CompareAndSplit(const Register& lhs,
1496                        const Operand& rhs,
1497                        Condition cond,
1498                        Label* if_true,
1499                        Label* if_false,
1500                        Label* fall_through);
1501 
1502   // Test the bits of register defined by bit_pattern, and branch to
1503   // if_any_set, if_all_clear or fall_through accordingly.
1504   void TestAndSplit(const Register& reg,
1505                     uint64_t bit_pattern,
1506                     Label* if_all_clear,
1507                     Label* if_any_set,
1508                     Label* fall_through);
1509 
1510   // Check if a map for a JSObject indicates that the object has fast elements.
1511   // Jump to the specified label if it does not.
1512   void CheckFastElements(Register map, Register scratch, Label* fail);
1513 
1514   // Check if a map for a JSObject indicates that the object can have both smi
1515   // and HeapObject elements.  Jump to the specified label if it does not.
1516   void CheckFastObjectElements(Register map, Register scratch, Label* fail);
1517 
1518   // Check to see if number can be stored as a double in FastDoubleElements.
1519   // If it can, store it at the index specified by key_reg in the array,
1520   // otherwise jump to fail.
1521   void StoreNumberToDoubleElements(Register value_reg,
1522                                    Register key_reg,
1523                                    Register elements_reg,
1524                                    Register scratch1,
1525                                    FPRegister fpscratch1,
1526                                    Label* fail,
1527                                    int elements_offset = 0);
1528 
1529   // Picks out an array index from the hash field.
1530   // Register use:
1531   //   hash - holds the index's hash. Clobbered.
1532   //   index - holds the overwritten index on exit.
1533   void IndexFromHash(Register hash, Register index);
1534 
1535   // ---------------------------------------------------------------------------
1536   // Inline caching support.
1537 
1538   void EmitSeqStringSetCharCheck(Register string,
1539                                  Register index,
1540                                  SeqStringSetCharCheckIndexType index_type,
1541                                  Register scratch,
1542                                  uint32_t encoding_mask);
1543 
1544   // Generate code for checking access rights - used for security checks
1545   // on access to global objects across environments. The holder register
1546   // is left untouched, whereas both scratch registers are clobbered.
1547   void CheckAccessGlobalProxy(Register holder_reg,
1548                               Register scratch1,
1549                               Register scratch2,
1550                               Label* miss);
1551 
1552   // Hash the interger value in 'key' register.
1553   // It uses the same algorithm as ComputeIntegerHash in utils.h.
1554   void GetNumberHash(Register key, Register scratch);
1555 
1556   // Load value from the dictionary.
1557   //
1558   // elements - holds the slow-case elements of the receiver on entry.
1559   //            Unchanged unless 'result' is the same register.
1560   //
1561   // key      - holds the smi key on entry.
1562   //            Unchanged unless 'result' is the same register.
1563   //
1564   // result   - holds the result on exit if the load succeeded.
1565   //            Allowed to be the same as 'key' or 'result'.
1566   //            Unchanged on bailout so 'key' or 'result' can be used
1567   //            in further computation.
1568   void LoadFromNumberDictionary(Label* miss,
1569                                 Register elements,
1570                                 Register key,
1571                                 Register result,
1572                                 Register scratch0,
1573                                 Register scratch1,
1574                                 Register scratch2,
1575                                 Register scratch3);
1576 
1577   // ---------------------------------------------------------------------------
1578   // Frames.
1579 
1580   // Load the type feedback vector from a JavaScript frame.
1581   void EmitLoadTypeFeedbackVector(Register vector);
1582 
1583   // Activation support.
1584   void EnterFrame(StackFrame::Type type);
1585   void EnterFrame(StackFrame::Type type, bool load_constant_pool_pointer_reg);
1586   void LeaveFrame(StackFrame::Type type);
1587 
1588   // Returns map with validated enum cache in object register.
1589   void CheckEnumCache(Register object,
1590                       Register null_value,
1591                       Register scratch0,
1592                       Register scratch1,
1593                       Register scratch2,
1594                       Register scratch3,
1595                       Label* call_runtime);
1596 
1597   // AllocationMemento support. Arrays may have an associated
1598   // AllocationMemento object that can be checked for in order to pretransition
1599   // to another type.
1600   // On entry, receiver should point to the array object.
1601   // If allocation info is present, the Z flag is set (so that the eq
1602   // condition will pass).
1603   void TestJSArrayForAllocationMemento(Register receiver,
1604                                        Register scratch1,
1605                                        Register scratch2,
1606                                        Label* no_memento_found);
1607 
JumpIfJSArrayHasAllocationMemento(Register receiver,Register scratch1,Register scratch2,Label * memento_found)1608   void JumpIfJSArrayHasAllocationMemento(Register receiver,
1609                                          Register scratch1,
1610                                          Register scratch2,
1611                                          Label* memento_found) {
1612     Label no_memento_found;
1613     TestJSArrayForAllocationMemento(receiver, scratch1, scratch2,
1614                                     &no_memento_found);
1615     B(eq, memento_found);
1616     Bind(&no_memento_found);
1617   }
1618 
1619   // The stack pointer has to switch between csp and jssp when setting up and
1620   // destroying the exit frame. Hence preserving/restoring the registers is
1621   // slightly more complicated than simple push/pop operations.
1622   void ExitFramePreserveFPRegs();
1623   void ExitFrameRestoreFPRegs();
1624 
1625   // Generates function and stub prologue code.
1626   void StubPrologue();
1627   void Prologue(bool code_pre_aging);
1628 
1629   // Enter exit frame. Exit frames are used when calling C code from generated
1630   // (JavaScript) code.
1631   //
1632   // The stack pointer must be jssp on entry, and will be set to csp by this
1633   // function. The frame pointer is also configured, but the only other
1634   // registers modified by this function are the provided scratch register, and
1635   // jssp.
1636   //
1637   // The 'extra_space' argument can be used to allocate some space in the exit
1638   // frame that will be ignored by the GC. This space will be reserved in the
1639   // bottom of the frame immediately above the return address slot.
1640   //
1641   // Set up a stack frame and registers as follows:
1642   //         fp[8]: CallerPC (lr)
1643   //   fp -> fp[0]: CallerFP (old fp)
1644   //         fp[-8]: SPOffset (new csp)
1645   //         fp[-16]: CodeObject()
1646   //         fp[-16 - fp-size]: Saved doubles, if saved_doubles is true.
1647   //         csp[8]: Memory reserved for the caller if extra_space != 0.
1648   //                 Alignment padding, if necessary.
1649   //  csp -> csp[0]: Space reserved for the return address.
1650   //
1651   // This function also stores the new frame information in the top frame, so
1652   // that the new frame becomes the current frame.
1653   void EnterExitFrame(bool save_doubles,
1654                       const Register& scratch,
1655                       int extra_space = 0);
1656 
1657   // Leave the current exit frame, after a C function has returned to generated
1658   // (JavaScript) code.
1659   //
1660   // This effectively unwinds the operation of EnterExitFrame:
1661   //  * Preserved doubles are restored (if restore_doubles is true).
1662   //  * The frame information is removed from the top frame.
1663   //  * The exit frame is dropped.
1664   //  * The stack pointer is reset to jssp.
1665   //
1666   // The stack pointer must be csp on entry.
1667   void LeaveExitFrame(bool save_doubles,
1668                       const Register& scratch,
1669                       bool restore_context);
1670 
1671   void LoadContext(Register dst, int context_chain_length);
1672 
1673   // Load the global object from the current context.
LoadGlobalObject(Register dst)1674   void LoadGlobalObject(Register dst) {
1675     LoadNativeContextSlot(Context::EXTENSION_INDEX, dst);
1676   }
1677 
1678   // Load the global proxy from the current context.
LoadGlobalProxy(Register dst)1679   void LoadGlobalProxy(Register dst) {
1680     LoadNativeContextSlot(Context::GLOBAL_PROXY_INDEX, dst);
1681   }
1682 
1683   // Emit code for a truncating division by a constant. The dividend register is
1684   // unchanged. Dividend and result must be different.
1685   void TruncatingDiv(Register result, Register dividend, int32_t divisor);
1686 
1687   // ---------------------------------------------------------------------------
1688   // StatsCounter support
1689 
1690   void SetCounter(StatsCounter* counter, int value, Register scratch1,
1691                   Register scratch2);
1692   void IncrementCounter(StatsCounter* counter, int value, Register scratch1,
1693                         Register scratch2);
1694   void DecrementCounter(StatsCounter* counter, int value, Register scratch1,
1695                         Register scratch2);
1696 
1697   // ---------------------------------------------------------------------------
1698   // Garbage collector support (GC).
1699 
1700   enum RememberedSetFinalAction {
1701     kReturnAtEnd,
1702     kFallThroughAtEnd
1703   };
1704 
1705   // Record in the remembered set the fact that we have a pointer to new space
1706   // at the address pointed to by the addr register. Only works if addr is not
1707   // in new space.
1708   void RememberedSetHelper(Register object,  // Used for debug code.
1709                            Register addr,
1710                            Register scratch1,
1711                            SaveFPRegsMode save_fp,
1712                            RememberedSetFinalAction and_then);
1713 
1714   // Push and pop the registers that can hold pointers, as defined by the
1715   // RegList constant kSafepointSavedRegisters.
1716   void PushSafepointRegisters();
1717   void PopSafepointRegisters();
1718 
1719   void PushSafepointRegistersAndDoubles();
1720   void PopSafepointRegistersAndDoubles();
1721 
1722   // Store value in register src in the safepoint stack slot for register dst.
StoreToSafepointRegisterSlot(Register src,Register dst)1723   void StoreToSafepointRegisterSlot(Register src, Register dst) {
1724     Poke(src, SafepointRegisterStackIndex(dst.code()) * kPointerSize);
1725   }
1726 
1727   // Load the value of the src register from its safepoint stack slot
1728   // into register dst.
LoadFromSafepointRegisterSlot(Register dst,Register src)1729   void LoadFromSafepointRegisterSlot(Register dst, Register src) {
1730     Peek(src, SafepointRegisterStackIndex(dst.code()) * kPointerSize);
1731   }
1732 
1733   void CheckPageFlagSet(const Register& object,
1734                         const Register& scratch,
1735                         int mask,
1736                         Label* if_any_set);
1737 
1738   void CheckPageFlagClear(const Register& object,
1739                           const Register& scratch,
1740                           int mask,
1741                           Label* if_all_clear);
1742 
1743   // Check if object is in new space and jump accordingly.
1744   // Register 'object' is preserved.
JumpIfNotInNewSpace(Register object,Label * branch)1745   void JumpIfNotInNewSpace(Register object,
1746                            Label* branch) {
1747     InNewSpace(object, ne, branch);
1748   }
1749 
JumpIfInNewSpace(Register object,Label * branch)1750   void JumpIfInNewSpace(Register object,
1751                         Label* branch) {
1752     InNewSpace(object, eq, branch);
1753   }
1754 
1755   // Notify the garbage collector that we wrote a pointer into an object.
1756   // |object| is the object being stored into, |value| is the object being
1757   // stored.  value and scratch registers are clobbered by the operation.
1758   // The offset is the offset from the start of the object, not the offset from
1759   // the tagged HeapObject pointer.  For use with FieldMemOperand(reg, off).
1760   void RecordWriteField(
1761       Register object,
1762       int offset,
1763       Register value,
1764       Register scratch,
1765       LinkRegisterStatus lr_status,
1766       SaveFPRegsMode save_fp,
1767       RememberedSetAction remembered_set_action = EMIT_REMEMBERED_SET,
1768       SmiCheck smi_check = INLINE_SMI_CHECK,
1769       PointersToHereCheck pointers_to_here_check_for_value =
1770           kPointersToHereMaybeInteresting);
1771 
1772   // As above, but the offset has the tag presubtracted. For use with
1773   // MemOperand(reg, off).
1774   inline void RecordWriteContextSlot(
1775       Register context,
1776       int offset,
1777       Register value,
1778       Register scratch,
1779       LinkRegisterStatus lr_status,
1780       SaveFPRegsMode save_fp,
1781       RememberedSetAction remembered_set_action = EMIT_REMEMBERED_SET,
1782       SmiCheck smi_check = INLINE_SMI_CHECK,
1783       PointersToHereCheck pointers_to_here_check_for_value =
1784           kPointersToHereMaybeInteresting) {
1785     RecordWriteField(context,
1786                      offset + kHeapObjectTag,
1787                      value,
1788                      scratch,
1789                      lr_status,
1790                      save_fp,
1791                      remembered_set_action,
1792                      smi_check,
1793                      pointers_to_here_check_for_value);
1794   }
1795 
1796   void RecordWriteForMap(
1797       Register object,
1798       Register map,
1799       Register dst,
1800       LinkRegisterStatus lr_status,
1801       SaveFPRegsMode save_fp);
1802 
1803   // For a given |object| notify the garbage collector that the slot |address|
1804   // has been written.  |value| is the object being stored. The value and
1805   // address registers are clobbered by the operation.
1806   void RecordWrite(
1807       Register object,
1808       Register address,
1809       Register value,
1810       LinkRegisterStatus lr_status,
1811       SaveFPRegsMode save_fp,
1812       RememberedSetAction remembered_set_action = EMIT_REMEMBERED_SET,
1813       SmiCheck smi_check = INLINE_SMI_CHECK,
1814       PointersToHereCheck pointers_to_here_check_for_value =
1815           kPointersToHereMaybeInteresting);
1816 
1817   // Checks the color of an object.  If the object is white we jump to the
1818   // incremental marker.
1819   void JumpIfWhite(Register value, Register scratch1, Register scratch2,
1820                    Register scratch3, Register scratch4, Label* value_is_white);
1821 
1822   // Helper for finding the mark bits for an address.
1823   // Note that the behaviour slightly differs from other architectures.
1824   // On exit:
1825   //  - addr_reg is unchanged.
1826   //  - The bitmap register points at the word with the mark bits.
1827   //  - The shift register contains the index of the first color bit for this
1828   //    object in the bitmap.
1829   inline void GetMarkBits(Register addr_reg,
1830                           Register bitmap_reg,
1831                           Register shift_reg);
1832 
1833   // Check if an object has a given incremental marking color.
1834   void HasColor(Register object,
1835                 Register scratch0,
1836                 Register scratch1,
1837                 Label* has_color,
1838                 int first_bit,
1839                 int second_bit);
1840 
1841   void JumpIfBlack(Register object,
1842                    Register scratch0,
1843                    Register scratch1,
1844                    Label* on_black);
1845 
1846 
1847   // ---------------------------------------------------------------------------
1848   // Debugging.
1849 
1850   // Calls Abort(msg) if the condition cond is not satisfied.
1851   // Use --debug_code to enable.
1852   void Assert(Condition cond, BailoutReason reason);
1853   void AssertRegisterIsClear(Register reg, BailoutReason reason);
1854   void AssertRegisterIsRoot(
1855       Register reg,
1856       Heap::RootListIndex index,
1857       BailoutReason reason = kRegisterDidNotMatchExpectedRoot);
1858   void AssertFastElements(Register elements);
1859 
1860   // Abort if the specified register contains the invalid color bit pattern.
1861   // The pattern must be in bits [1:0] of 'reg' register.
1862   //
1863   // If emit_debug_code() is false, this emits no code.
1864   void AssertHasValidColor(const Register& reg);
1865 
1866   // Abort if 'object' register doesn't point to a string object.
1867   //
1868   // If emit_debug_code() is false, this emits no code.
1869   void AssertIsString(const Register& object);
1870 
1871   // Like Assert(), but always enabled.
1872   void Check(Condition cond, BailoutReason reason);
1873   void CheckRegisterIsClear(Register reg, BailoutReason reason);
1874 
1875   // Print a message to stderr and abort execution.
1876   void Abort(BailoutReason reason);
1877 
1878   // Conditionally load the cached Array transitioned map of type
1879   // transitioned_kind from the native context if the map in register
1880   // map_in_out is the cached Array map in the native context of
1881   // expected_kind.
1882   void LoadTransitionedArrayMapConditional(
1883       ElementsKind expected_kind,
1884       ElementsKind transitioned_kind,
1885       Register map_in_out,
1886       Register scratch1,
1887       Register scratch2,
1888       Label* no_map_match);
1889 
1890   void LoadNativeContextSlot(int index, Register dst);
1891 
1892   // Load the initial map from the global function. The registers function and
1893   // map can be the same, function is then overwritten.
1894   void LoadGlobalFunctionInitialMap(Register function,
1895                                     Register map,
1896                                     Register scratch);
1897 
TmpList()1898   CPURegList* TmpList() { return &tmp_list_; }
FPTmpList()1899   CPURegList* FPTmpList() { return &fptmp_list_; }
1900 
1901   static CPURegList DefaultTmpList();
1902   static CPURegList DefaultFPTmpList();
1903 
1904   // Like printf, but print at run-time from generated code.
1905   //
1906   // The caller must ensure that arguments for floating-point placeholders
1907   // (such as %e, %f or %g) are FPRegisters, and that arguments for integer
1908   // placeholders are Registers.
1909   //
1910   // At the moment it is only possible to print the value of csp if it is the
1911   // current stack pointer. Otherwise, the MacroAssembler will automatically
1912   // update csp on every push (using BumpSystemStackPointer), so determining its
1913   // value is difficult.
1914   //
1915   // Format placeholders that refer to more than one argument, or to a specific
1916   // argument, are not supported. This includes formats like "%1$d" or "%.*d".
1917   //
1918   // This function automatically preserves caller-saved registers so that
1919   // calling code can use Printf at any point without having to worry about
1920   // corruption. The preservation mechanism generates a lot of code. If this is
1921   // a problem, preserve the important registers manually and then call
1922   // PrintfNoPreserve. Callee-saved registers are not used by Printf, and are
1923   // implicitly preserved.
1924   void Printf(const char * format,
1925               CPURegister arg0 = NoCPUReg,
1926               CPURegister arg1 = NoCPUReg,
1927               CPURegister arg2 = NoCPUReg,
1928               CPURegister arg3 = NoCPUReg);
1929 
1930   // Like Printf, but don't preserve any caller-saved registers, not even 'lr'.
1931   //
1932   // The return code from the system printf call will be returned in x0.
1933   void PrintfNoPreserve(const char * format,
1934                         const CPURegister& arg0 = NoCPUReg,
1935                         const CPURegister& arg1 = NoCPUReg,
1936                         const CPURegister& arg2 = NoCPUReg,
1937                         const CPURegister& arg3 = NoCPUReg);
1938 
1939   // Code ageing support functions.
1940 
1941   // Code ageing on ARM64 works similarly to on ARM. When V8 wants to mark a
1942   // function as old, it replaces some of the function prologue (generated by
1943   // FullCodeGenerator::Generate) with a call to a special stub (ultimately
1944   // generated by GenerateMakeCodeYoungAgainCommon). The stub restores the
1945   // function prologue to its initial young state (indicating that it has been
1946   // recently run) and continues. A young function is therefore one which has a
1947   // normal frame setup sequence, and an old function has a code age sequence
1948   // which calls a code ageing stub.
1949 
1950   // Set up a basic stack frame for young code (or code exempt from ageing) with
1951   // type FUNCTION. It may be patched later for code ageing support. This is
1952   // done by to Code::PatchPlatformCodeAge and EmitCodeAgeSequence.
1953   //
1954   // This function takes an Assembler so it can be called from either a
1955   // MacroAssembler or a PatchingAssembler context.
1956   static void EmitFrameSetupForCodeAgePatching(Assembler* assm);
1957 
1958   // Call EmitFrameSetupForCodeAgePatching from a MacroAssembler context.
1959   void EmitFrameSetupForCodeAgePatching();
1960 
1961   // Emit a code age sequence that calls the relevant code age stub. The code
1962   // generated by this sequence is expected to replace the code generated by
1963   // EmitFrameSetupForCodeAgePatching, and represents an old function.
1964   //
1965   // If stub is NULL, this function generates the code age sequence but omits
1966   // the stub address that is normally embedded in the instruction stream. This
1967   // can be used by debug code to verify code age sequences.
1968   static void EmitCodeAgeSequence(Assembler* assm, Code* stub);
1969 
1970   // Call EmitCodeAgeSequence from a MacroAssembler context.
1971   void EmitCodeAgeSequence(Code* stub);
1972 
1973   // Return true if the sequence is a young sequence geneated by
1974   // EmitFrameSetupForCodeAgePatching. Otherwise, this method asserts that the
1975   // sequence is a code age sequence (emitted by EmitCodeAgeSequence).
1976   static bool IsYoungSequence(Isolate* isolate, byte* sequence);
1977 
1978   // Jumps to found label if a prototype map has dictionary elements.
1979   void JumpIfDictionaryInPrototypeChain(Register object, Register scratch0,
1980                                         Register scratch1, Label* found);
1981 
1982   // Perform necessary maintenance operations before a push or after a pop.
1983   //
1984   // Note that size is specified in bytes.
1985   void PushPreamble(Operand total_size);
1986   void PopPostamble(Operand total_size);
1987 
PushPreamble(int count,int size)1988   void PushPreamble(int count, int size) { PushPreamble(count * size); }
PopPostamble(int count,int size)1989   void PopPostamble(int count, int size) { PopPostamble(count * size); }
1990 
1991  private:
1992   // The actual Push and Pop implementations. These don't generate any code
1993   // other than that required for the push or pop. This allows
1994   // (Push|Pop)CPURegList to bundle together run-time assertions for a large
1995   // block of registers.
1996   //
1997   // Note that size is per register, and is specified in bytes.
1998   void PushHelper(int count, int size,
1999                   const CPURegister& src0, const CPURegister& src1,
2000                   const CPURegister& src2, const CPURegister& src3);
2001   void PopHelper(int count, int size,
2002                  const CPURegister& dst0, const CPURegister& dst1,
2003                  const CPURegister& dst2, const CPURegister& dst3);
2004 
2005   // Call Printf. On a native build, a simple call will be generated, but if the
2006   // simulator is being used then a suitable pseudo-instruction is used. The
2007   // arguments and stack (csp) must be prepared by the caller as for a normal
2008   // AAPCS64 call to 'printf'.
2009   //
2010   // The 'args' argument should point to an array of variable arguments in their
2011   // proper PCS registers (and in calling order). The argument registers can
2012   // have mixed types. The format string (x0) should not be included.
2013   void CallPrintf(int arg_count = 0, const CPURegister * args = NULL);
2014 
2015   // Helper for implementing JumpIfNotInNewSpace and JumpIfInNewSpace.
2016   void InNewSpace(Register object,
2017                   Condition cond,  // eq for new space, ne otherwise.
2018                   Label* branch);
2019 
2020   // Try to represent a double as an int so that integer fast-paths may be
2021   // used. Not every valid integer value is guaranteed to be caught.
2022   // It supports both 32-bit and 64-bit integers depending whether 'as_int'
2023   // is a W or X register.
2024   //
2025   // This does not distinguish between +0 and -0, so if this distinction is
2026   // important it must be checked separately.
2027   //
2028   // On output the Z flag is set if the operation was successful.
2029   void TryRepresentDoubleAsInt(Register as_int,
2030                                FPRegister value,
2031                                FPRegister scratch_d,
2032                                Label* on_successful_conversion = NULL,
2033                                Label* on_failed_conversion = NULL);
2034 
2035   bool generating_stub_;
2036 #if DEBUG
2037   // Tell whether any of the macro instruction can be used. When false the
2038   // MacroAssembler will assert if a method which can emit a variable number
2039   // of instructions is called.
2040   bool allow_macro_instructions_;
2041 #endif
2042   bool has_frame_;
2043 
2044   // The Abort method should call a V8 runtime function, but the CallRuntime
2045   // mechanism depends on CEntryStub. If use_real_aborts is false, Abort will
2046   // use a simpler abort mechanism that doesn't depend on CEntryStub.
2047   //
2048   // The purpose of this is to allow Aborts to be compiled whilst CEntryStub is
2049   // being generated.
2050   bool use_real_aborts_;
2051 
2052   // This handle will be patched with the code object on installation.
2053   Handle<Object> code_object_;
2054 
2055   // The register to use as a stack pointer for stack operations.
2056   Register sp_;
2057 
2058   // Scratch registers available for use by the MacroAssembler.
2059   CPURegList tmp_list_;
2060   CPURegList fptmp_list_;
2061 
2062   void InitializeNewString(Register string,
2063                            Register length,
2064                            Heap::RootListIndex map_index,
2065                            Register scratch1,
2066                            Register scratch2);
2067 
2068  public:
2069   // Far branches resolving.
2070   //
2071   // The various classes of branch instructions with immediate offsets have
2072   // different ranges. While the Assembler will fail to assemble a branch
2073   // exceeding its range, the MacroAssembler offers a mechanism to resolve
2074   // branches to too distant targets, either by tweaking the generated code to
2075   // use branch instructions with wider ranges or generating veneers.
2076   //
2077   // Currently branches to distant targets are resolved using unconditional
2078   // branch isntructions with a range of +-128MB. If that becomes too little
2079   // (!), the mechanism can be extended to generate special veneers for really
2080   // far targets.
2081 
2082   // Helps resolve branching to labels potentially out of range.
2083   // If the label is not bound, it registers the information necessary to later
2084   // be able to emit a veneer for this branch if necessary.
2085   // If the label is bound, it returns true if the label (or the previous link
2086   // in the label chain) is out of range. In that case the caller is responsible
2087   // for generating appropriate code.
2088   // Otherwise it returns false.
2089   // This function also checks wether veneers need to be emitted.
2090   bool NeedExtraInstructionsOrRegisterBranch(Label *label,
2091                                              ImmBranchType branch_type);
2092 };
2093 
2094 
2095 // Use this scope when you need a one-to-one mapping bewteen methods and
2096 // instructions. This scope prevents the MacroAssembler from being called and
2097 // literal pools from being emitted. It also asserts the number of instructions
2098 // emitted is what you specified when creating the scope.
2099 class InstructionAccurateScope BASE_EMBEDDED {
2100  public:
2101   explicit InstructionAccurateScope(MacroAssembler* masm, size_t count = 0)
masm_(masm)2102       : masm_(masm)
2103 #ifdef DEBUG
2104         ,
2105         size_(count * kInstructionSize)
2106 #endif
2107   {
2108     // Before blocking the const pool, see if it needs to be emitted.
2109     masm_->CheckConstPool(false, true);
2110     masm_->CheckVeneerPool(false, true);
2111 
2112     masm_->StartBlockPools();
2113 #ifdef DEBUG
2114     if (count != 0) {
2115       masm_->bind(&start_);
2116     }
2117     previous_allow_macro_instructions_ = masm_->allow_macro_instructions();
2118     masm_->set_allow_macro_instructions(false);
2119 #endif
2120   }
2121 
~InstructionAccurateScope()2122   ~InstructionAccurateScope() {
2123     masm_->EndBlockPools();
2124 #ifdef DEBUG
2125     if (start_.is_bound()) {
2126       DCHECK(masm_->SizeOfCodeGeneratedSince(&start_) == size_);
2127     }
2128     masm_->set_allow_macro_instructions(previous_allow_macro_instructions_);
2129 #endif
2130   }
2131 
2132  private:
2133   MacroAssembler* masm_;
2134 #ifdef DEBUG
2135   size_t size_;
2136   Label start_;
2137   bool previous_allow_macro_instructions_;
2138 #endif
2139 };
2140 
2141 
2142 // This scope utility allows scratch registers to be managed safely. The
2143 // MacroAssembler's TmpList() (and FPTmpList()) is used as a pool of scratch
2144 // registers. These registers can be allocated on demand, and will be returned
2145 // at the end of the scope.
2146 //
2147 // When the scope ends, the MacroAssembler's lists will be restored to their
2148 // original state, even if the lists were modified by some other means.
2149 class UseScratchRegisterScope {
2150  public:
UseScratchRegisterScope(MacroAssembler * masm)2151   explicit UseScratchRegisterScope(MacroAssembler* masm)
2152       : available_(masm->TmpList()),
2153         availablefp_(masm->FPTmpList()),
2154         old_available_(available_->list()),
2155         old_availablefp_(availablefp_->list()) {
2156     DCHECK(available_->type() == CPURegister::kRegister);
2157     DCHECK(availablefp_->type() == CPURegister::kFPRegister);
2158   }
2159 
2160   ~UseScratchRegisterScope();
2161 
2162   // Take a register from the appropriate temps list. It will be returned
2163   // automatically when the scope ends.
AcquireW()2164   Register AcquireW() { return AcquireNextAvailable(available_).W(); }
AcquireX()2165   Register AcquireX() { return AcquireNextAvailable(available_).X(); }
AcquireS()2166   FPRegister AcquireS() { return AcquireNextAvailable(availablefp_).S(); }
AcquireD()2167   FPRegister AcquireD() { return AcquireNextAvailable(availablefp_).D(); }
2168 
UnsafeAcquire(const Register & reg)2169   Register UnsafeAcquire(const Register& reg) {
2170     return Register(UnsafeAcquire(available_, reg));
2171   }
2172 
2173   Register AcquireSameSizeAs(const Register& reg);
2174   FPRegister AcquireSameSizeAs(const FPRegister& reg);
2175 
2176  private:
2177   static CPURegister AcquireNextAvailable(CPURegList* available);
2178   static CPURegister UnsafeAcquire(CPURegList* available,
2179                                    const CPURegister& reg);
2180 
2181   // Available scratch registers.
2182   CPURegList* available_;     // kRegister
2183   CPURegList* availablefp_;   // kFPRegister
2184 
2185   // The state of the available lists at the start of this scope.
2186   RegList old_available_;     // kRegister
2187   RegList old_availablefp_;   // kFPRegister
2188 };
2189 
2190 
2191 inline MemOperand ContextMemOperand(Register context, int index = 0) {
2192   return MemOperand(context, Context::SlotOffset(index));
2193 }
2194 
NativeContextMemOperand()2195 inline MemOperand NativeContextMemOperand() {
2196   return ContextMemOperand(cp, Context::NATIVE_CONTEXT_INDEX);
2197 }
2198 
2199 
2200 // Encode and decode information about patchable inline SMI checks.
2201 class InlineSmiCheckInfo {
2202  public:
2203   explicit InlineSmiCheckInfo(Address info);
2204 
HasSmiCheck()2205   bool HasSmiCheck() const {
2206     return smi_check_ != NULL;
2207   }
2208 
SmiRegister()2209   const Register& SmiRegister() const {
2210     return reg_;
2211   }
2212 
SmiCheck()2213   Instruction* SmiCheck() const {
2214     return smi_check_;
2215   }
2216 
2217   // Use MacroAssembler::InlineData to emit information about patchable inline
2218   // SMI checks. The caller may specify 'reg' as NoReg and an unbound 'site' to
2219   // indicate that there is no inline SMI check. Note that 'reg' cannot be csp.
2220   //
2221   // The generated patch information can be read using the InlineSMICheckInfo
2222   // class.
2223   static void Emit(MacroAssembler* masm, const Register& reg,
2224                    const Label* smi_check);
2225 
2226   // Emit information to indicate that there is no inline SMI check.
EmitNotInlined(MacroAssembler * masm)2227   static void EmitNotInlined(MacroAssembler* masm) {
2228     Label unbound;
2229     Emit(masm, NoReg, &unbound);
2230   }
2231 
2232  private:
2233   Register reg_;
2234   Instruction* smi_check_;
2235 
2236   // Fields in the data encoded by InlineData.
2237 
2238   // A width of 5 (Rd_width) for the SMI register preclues the use of csp,
2239   // since kSPRegInternalCode is 63. However, csp should never hold a SMI or be
2240   // used in a patchable check. The Emit() method checks this.
2241   //
2242   // Note that the total size of the fields is restricted by the underlying
2243   // storage size handled by the BitField class, which is a uint32_t.
2244   class RegisterBits : public BitField<unsigned, 0, 5> {};
2245   class DeltaBits : public BitField<uint32_t, 5, 32-5> {};
2246 };
2247 
2248 }  // namespace internal
2249 }  // namespace v8
2250 
2251 #ifdef GENERATED_CODE_COVERAGE
2252 #error "Unsupported option"
2253 #define CODE_COVERAGE_STRINGIFY(x) #x
2254 #define CODE_COVERAGE_TOSTRING(x) CODE_COVERAGE_STRINGIFY(x)
2255 #define __FILE_LINE__ __FILE__ ":" CODE_COVERAGE_TOSTRING(__LINE__)
2256 #define ACCESS_MASM(masm) masm->stop(__FILE_LINE__); masm->
2257 #else
2258 #define ACCESS_MASM(masm) masm->
2259 #endif
2260 
2261 #endif  // V8_ARM64_MACRO_ASSEMBLER_ARM64_H_
2262