1 /**************************************************************************
2 *
3 * Copyright 2009 Marek Olšák <maraeo@gmail.com>
4 *
5 * Permission is hereby granted, free of charge, to any person obtaining a
6 * copy of this software and associated documentation files (the
7 * "Software"), to deal in the Software without restriction, including
8 * without limitation the rights to use, copy, modify, merge, publish,
9 * distribute, sub license, and/or sell copies of the Software, and to
10 * permit persons to whom the Software is furnished to do so, subject to
11 * the following conditions:
12 *
13 * The above copyright notice and this permission notice (including the
14 * next paragraph) shall be included in all copies or substantial portions
15 * of the Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
18 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
19 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
20 * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
21 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
22 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
23 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
24 *
25 **************************************************************************/
26
27 /* This file contains the vertex shader tranformations for SW TCL needed
28 * to overcome the limitations of the r300 rasterizer.
29 *
30 * Transformations:
31 * 1) If the secondary color output is present, the primary color must be
32 * present too.
33 * 2) If any back-face color output is present, there must be all 4 color
34 * outputs and missing ones must be inserted.
35 * 3) Insert a trailing texcoord output containing a copy of POS, for WPOS.
36 *
37 * I know this code is cumbersome, but I don't know of any nicer way
38 * of transforming TGSI shaders. ~ M.
39 */
40
41 #include "r300_vs.h"
42
43 #include <stdio.h>
44
45 #include "tgsi/tgsi_transform.h"
46 #include "tgsi/tgsi_dump.h"
47
48 #include "draw/draw_context.h"
49
50 struct vs_transform_context {
51 struct tgsi_transform_context base;
52
53 boolean color_used[2];
54 boolean bcolor_used[2];
55
56 /* Index of the pos output, typically 0. */
57 unsigned pos_output;
58 /* Index of the pos temp where all writes of pos are redirected to. */
59 unsigned pos_temp;
60 /* The index of the last generic output, after which we insert a new
61 * output for WPOS. */
62 int last_generic;
63
64 unsigned num_outputs;
65 /* Used to shift output decl. indices when inserting new ones. */
66 unsigned decl_shift;
67 /* Used to remap writes to output decls if their indices changed. */
68 unsigned out_remap[32];
69
70 /* First instruction processed? */
71 boolean first_instruction;
72 /* End instruction processed? */
73 boolean end_instruction;
74
75 boolean temp_used[1024];
76 };
77
emit_temp(struct tgsi_transform_context * ctx,unsigned reg)78 static void emit_temp(struct tgsi_transform_context *ctx, unsigned reg)
79 {
80 struct tgsi_full_declaration decl;
81
82 decl = tgsi_default_full_declaration();
83 decl.Declaration.File = TGSI_FILE_TEMPORARY;
84 decl.Range.First = decl.Range.Last = reg;
85 ctx->emit_declaration(ctx, &decl);
86 }
87
emit_output(struct tgsi_transform_context * ctx,unsigned name,unsigned index,unsigned interp,unsigned reg)88 static void emit_output(struct tgsi_transform_context *ctx,
89 unsigned name, unsigned index, unsigned interp,
90 unsigned reg)
91 {
92 struct vs_transform_context *vsctx = (struct vs_transform_context *)ctx;
93 struct tgsi_full_declaration decl;
94
95 decl = tgsi_default_full_declaration();
96 decl.Declaration.File = TGSI_FILE_OUTPUT;
97 decl.Declaration.Interpolate = 1;
98 decl.Declaration.Semantic = TRUE;
99 decl.Semantic.Name = name;
100 decl.Semantic.Index = index;
101 decl.Range.First = decl.Range.Last = reg;
102 decl.Interp.Interpolate = interp;
103 ctx->emit_declaration(ctx, &decl);
104 ++vsctx->num_outputs;
105 }
106
insert_output_before(struct tgsi_transform_context * ctx,struct tgsi_full_declaration * before,unsigned name,unsigned index,unsigned interp)107 static void insert_output_before(struct tgsi_transform_context *ctx,
108 struct tgsi_full_declaration *before,
109 unsigned name, unsigned index, unsigned interp)
110 {
111 struct vs_transform_context *vsctx = (struct vs_transform_context *)ctx;
112 unsigned i;
113
114 /* Make a place for the new output. */
115 for (i = before->Range.First; i < ARRAY_SIZE(vsctx->out_remap); i++) {
116 ++vsctx->out_remap[i];
117 }
118
119 /* Insert the new output. */
120 emit_output(ctx, name, index, interp,
121 before->Range.First + vsctx->decl_shift);
122
123 ++vsctx->decl_shift;
124 }
125
insert_output_after(struct tgsi_transform_context * ctx,struct tgsi_full_declaration * after,unsigned name,unsigned index,unsigned interp)126 static void insert_output_after(struct tgsi_transform_context *ctx,
127 struct tgsi_full_declaration *after,
128 unsigned name, unsigned index, unsigned interp)
129 {
130 struct vs_transform_context *vsctx = (struct vs_transform_context *)ctx;
131 unsigned i;
132
133 /* Make a place for the new output. */
134 for (i = after->Range.First+1; i < ARRAY_SIZE(vsctx->out_remap); i++) {
135 ++vsctx->out_remap[i];
136 }
137
138 /* Insert the new output. */
139 emit_output(ctx, name, index, interp,
140 after->Range.First + 1);
141
142 ++vsctx->decl_shift;
143 }
144
transform_decl(struct tgsi_transform_context * ctx,struct tgsi_full_declaration * decl)145 static void transform_decl(struct tgsi_transform_context *ctx,
146 struct tgsi_full_declaration *decl)
147 {
148 struct vs_transform_context *vsctx = (struct vs_transform_context *)ctx;
149 unsigned i;
150
151 if (decl->Declaration.File == TGSI_FILE_OUTPUT) {
152 switch (decl->Semantic.Name) {
153 case TGSI_SEMANTIC_POSITION:
154 vsctx->pos_output = decl->Range.First;
155 break;
156
157 case TGSI_SEMANTIC_COLOR:
158 assert(decl->Semantic.Index < 2);
159
160 /* We must rasterize the first color if the second one is
161 * used, otherwise the rasterizer doesn't do the color
162 * selection correctly. Declare it, but don't write to it. */
163 if (decl->Semantic.Index == 1 && !vsctx->color_used[0]) {
164 insert_output_before(ctx, decl, TGSI_SEMANTIC_COLOR, 0,
165 TGSI_INTERPOLATE_LINEAR);
166 vsctx->color_used[0] = TRUE;
167 }
168 break;
169
170 case TGSI_SEMANTIC_BCOLOR:
171 assert(decl->Semantic.Index < 2);
172
173 /* We must rasterize all 4 colors if back-face colors are
174 * used, otherwise the rasterizer doesn't do the color
175 * selection correctly. Declare it, but don't write to it. */
176 if (!vsctx->color_used[0]) {
177 insert_output_before(ctx, decl, TGSI_SEMANTIC_COLOR, 0,
178 TGSI_INTERPOLATE_LINEAR);
179 vsctx->color_used[0] = TRUE;
180 }
181 if (!vsctx->color_used[1]) {
182 insert_output_before(ctx, decl, TGSI_SEMANTIC_COLOR, 1,
183 TGSI_INTERPOLATE_LINEAR);
184 vsctx->color_used[1] = TRUE;
185 }
186 if (decl->Semantic.Index == 1 && !vsctx->bcolor_used[0]) {
187 insert_output_before(ctx, decl, TGSI_SEMANTIC_BCOLOR, 0,
188 TGSI_INTERPOLATE_LINEAR);
189 vsctx->bcolor_used[0] = TRUE;
190 }
191 break;
192
193 case TGSI_SEMANTIC_GENERIC:
194 vsctx->last_generic = MAX2(vsctx->last_generic, decl->Semantic.Index);
195 break;
196 }
197
198 /* Since we're inserting new outputs in between, the following outputs
199 * should be moved to the right so that they don't overlap with
200 * the newly added ones. */
201 decl->Range.First += vsctx->decl_shift;
202 decl->Range.Last += vsctx->decl_shift;
203
204 ++vsctx->num_outputs;
205 } else if (decl->Declaration.File == TGSI_FILE_TEMPORARY) {
206 for (i = decl->Range.First; i <= decl->Range.Last; i++) {
207 vsctx->temp_used[i] = TRUE;
208 }
209 }
210
211 ctx->emit_declaration(ctx, decl);
212
213 /* Insert BCOLOR1 if needed. */
214 if (decl->Declaration.File == TGSI_FILE_OUTPUT &&
215 decl->Semantic.Name == TGSI_SEMANTIC_BCOLOR &&
216 !vsctx->bcolor_used[1]) {
217 insert_output_after(ctx, decl, TGSI_SEMANTIC_BCOLOR, 1,
218 TGSI_INTERPOLATE_LINEAR);
219 }
220 }
221
transform_inst(struct tgsi_transform_context * ctx,struct tgsi_full_instruction * inst)222 static void transform_inst(struct tgsi_transform_context *ctx,
223 struct tgsi_full_instruction *inst)
224 {
225 struct vs_transform_context *vsctx = (struct vs_transform_context *) ctx;
226 struct tgsi_full_instruction new_inst;
227 unsigned i;
228
229 if (!vsctx->first_instruction) {
230 vsctx->first_instruction = TRUE;
231
232 /* Insert the generic output for WPOS. */
233 emit_output(ctx, TGSI_SEMANTIC_GENERIC, vsctx->last_generic + 1,
234 TGSI_INTERPOLATE_PERSPECTIVE, vsctx->num_outputs);
235
236 /* Find a free temp for POSITION. */
237 for (i = 0; i < ARRAY_SIZE(vsctx->temp_used); i++) {
238 if (!vsctx->temp_used[i]) {
239 emit_temp(ctx, i);
240 vsctx->pos_temp = i;
241 break;
242 }
243 }
244 }
245
246 if (inst->Instruction.Opcode == TGSI_OPCODE_END) {
247 /* MOV OUT[pos_output], TEMP[pos_temp]; */
248 new_inst = tgsi_default_full_instruction();
249 new_inst.Instruction.Opcode = TGSI_OPCODE_MOV;
250 new_inst.Instruction.NumDstRegs = 1;
251 new_inst.Dst[0].Register.File = TGSI_FILE_OUTPUT;
252 new_inst.Dst[0].Register.Index = vsctx->pos_output;
253 new_inst.Dst[0].Register.WriteMask = TGSI_WRITEMASK_XYZW;
254 new_inst.Instruction.NumSrcRegs = 1;
255 new_inst.Src[0].Register.File = TGSI_FILE_TEMPORARY;
256 new_inst.Src[0].Register.Index = vsctx->pos_temp;
257 ctx->emit_instruction(ctx, &new_inst);
258
259 /* MOV OUT[n-1], TEMP[pos_temp]; */
260 new_inst = tgsi_default_full_instruction();
261 new_inst.Instruction.Opcode = TGSI_OPCODE_MOV;
262 new_inst.Instruction.NumDstRegs = 1;
263 new_inst.Dst[0].Register.File = TGSI_FILE_OUTPUT;
264 new_inst.Dst[0].Register.Index = vsctx->num_outputs - 1;
265 new_inst.Dst[0].Register.WriteMask = TGSI_WRITEMASK_XYZW;
266 new_inst.Instruction.NumSrcRegs = 1;
267 new_inst.Src[0].Register.File = TGSI_FILE_TEMPORARY;
268 new_inst.Src[0].Register.Index = vsctx->pos_temp;
269 ctx->emit_instruction(ctx, &new_inst);
270
271 vsctx->end_instruction = TRUE;
272 } else {
273 /* Not an END instruction. */
274 /* Fix writes to outputs. */
275 for (i = 0; i < inst->Instruction.NumDstRegs; i++) {
276 struct tgsi_full_dst_register *dst = &inst->Dst[i];
277 if (dst->Register.File == TGSI_FILE_OUTPUT) {
278 if (dst->Register.Index == vsctx->pos_output) {
279 /* Replace writes to OUT[pos_output] with TEMP[pos_temp]. */
280 dst->Register.File = TGSI_FILE_TEMPORARY;
281 dst->Register.Index = vsctx->pos_temp;
282 } else {
283 /* Not a position, good...
284 * Since we were changing the indices of output decls,
285 * we must redirect writes into them too. */
286 dst->Register.Index = vsctx->out_remap[dst->Register.Index];
287 }
288 }
289 }
290
291 /* Inserting 2 instructions before the END opcode moves all following
292 * labels by 2. Subroutines are always after the END opcode so
293 * they're always moved. */
294 if (inst->Instruction.Opcode == TGSI_OPCODE_CAL) {
295 inst->Label.Label += 2;
296 }
297 /* The labels of the following opcodes are moved only after
298 * the END opcode. */
299 if (vsctx->end_instruction &&
300 (inst->Instruction.Opcode == TGSI_OPCODE_IF ||
301 inst->Instruction.Opcode == TGSI_OPCODE_ELSE ||
302 inst->Instruction.Opcode == TGSI_OPCODE_BGNLOOP ||
303 inst->Instruction.Opcode == TGSI_OPCODE_ENDLOOP)) {
304 inst->Label.Label += 2;
305 }
306 }
307
308 ctx->emit_instruction(ctx, inst);
309 }
310
r300_draw_init_vertex_shader(struct r300_context * r300,struct r300_vertex_shader * vs)311 void r300_draw_init_vertex_shader(struct r300_context *r300,
312 struct r300_vertex_shader *vs)
313 {
314 struct draw_context *draw = r300->draw;
315 struct pipe_shader_state new_vs;
316 struct tgsi_shader_info info;
317 struct vs_transform_context transform;
318 const uint newLen = tgsi_num_tokens(vs->state.tokens) + 100 /* XXX */;
319 unsigned i;
320
321 tgsi_scan_shader(vs->state.tokens, &info);
322
323 new_vs.tokens = tgsi_alloc_tokens(newLen);
324 if (new_vs.tokens == NULL)
325 return;
326
327 memset(&transform, 0, sizeof(transform));
328 for (i = 0; i < ARRAY_SIZE(transform.out_remap); i++) {
329 transform.out_remap[i] = i;
330 }
331 transform.last_generic = -1;
332 transform.base.transform_instruction = transform_inst;
333 transform.base.transform_declaration = transform_decl;
334
335 for (i = 0; i < info.num_outputs; i++) {
336 unsigned index = info.output_semantic_index[i];
337
338 switch (info.output_semantic_name[i]) {
339 case TGSI_SEMANTIC_COLOR:
340 assert(index < 2);
341 transform.color_used[index] = TRUE;
342 break;
343
344 case TGSI_SEMANTIC_BCOLOR:
345 assert(index < 2);
346 transform.bcolor_used[index] = TRUE;
347 break;
348 }
349 }
350
351 tgsi_transform_shader(vs->state.tokens,
352 (struct tgsi_token*)new_vs.tokens,
353 newLen, &transform.base);
354
355 #if 0
356 printf("----------------------------------------------\norig shader:\n");
357 tgsi_dump(vs->state.tokens, 0);
358 printf("----------------------------------------------\nnew shader:\n");
359 tgsi_dump(new_vs.tokens, 0);
360 printf("----------------------------------------------\n");
361 #endif
362
363 /* Free old tokens. */
364 FREE((void*)vs->state.tokens);
365
366 vs->draw_vs = draw_create_vertex_shader(draw, &new_vs);
367
368 /* Instead of duplicating and freeing the tokens, copy the pointer directly. */
369 vs->state.tokens = new_vs.tokens;
370
371 /* Init the VS output table for the rasterizer. */
372 r300_init_vs_outputs(r300, vs);
373
374 /* Make the last generic be WPOS. */
375 vs->outputs.wpos = vs->outputs.generic[transform.last_generic + 1];
376 vs->outputs.generic[transform.last_generic + 1] = ATTR_UNUSED;
377 }
378