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authorBrian Paul <brian.paul@tungstengraphics.com>2008-05-14 12:53:03 -0600
committerBrian Paul <brian.paul@tungstengraphics.com>2008-05-14 12:53:03 -0600
commit6ca948a303e1af7ae66ea7082af741f6880887f2 (patch)
treea497895b6edac79d78853913ddd91080f05e18ac /src/mesa/shader/programopt.c
parent19ad9cf7741c641bd83d20485b32d11fe27ca8df (diff)
added _mesa_combine_parameter_lists()
cherry-picked from gallium-0.1
Diffstat (limited to 'src/mesa/shader/programopt.c')
-rw-r--r--src/mesa/shader/programopt.c96
1 files changed, 94 insertions, 2 deletions
diff --git a/src/mesa/shader/programopt.c b/src/mesa/shader/programopt.c
index fc5b0497fe..e6f065a33b 100644
--- a/src/mesa/shader/programopt.c
+++ b/src/mesa/shader/programopt.c
@@ -35,6 +35,7 @@
#include "context.h"
#include "prog_parameter.h"
#include "prog_statevars.h"
+#include "program.h"
#include "programopt.h"
#include "prog_instruction.h"
@@ -102,7 +103,7 @@ _mesa_insert_mvp_code(GLcontext *ctx, struct gl_vertex_program *vprog)
_mesa_copy_instructions (newInst + 4, vprog->Base.Instructions, origLen);
/* free old instructions */
- _mesa_free(vprog->Base.Instructions);
+ _mesa_free_instructions(vprog->Base.Instructions, origLen);
/* install new instructions */
vprog->Base.Instructions = newInst;
@@ -275,7 +276,7 @@ _mesa_append_fog_code(GLcontext *ctx, struct gl_fragment_program *fprog)
inst++;
/* free old instructions */
- _mesa_free(fprog->Base.Instructions);
+ _mesa_free_instructions(fprog->Base.Instructions, origLen);
/* install new instructions */
fprog->Base.Instructions = newInst;
@@ -365,3 +366,94 @@ _mesa_count_texture_instructions(struct gl_program *prog)
}
}
+
+/**
+ * Scan/rewrite program to remove reads of varying (output) registers.
+ * In GLSL vertex shaders, varying vars can be read and written.
+ * Normally, vertex varying vars are implemented as output registers.
+ * On some hardware, trying to read an output register causes trouble.
+ * So, rewrite the program to use a temporary register in this case.
+ */
+void
+_mesa_remove_varying_reads(struct gl_program *prog)
+{
+ GLuint i;
+ GLint outputMap[VERT_RESULT_MAX];
+ GLuint numVaryingReads = 0;
+
+ assert(prog->Target == GL_VERTEX_PROGRAM_ARB);
+
+ for (i = 0; i < VERT_RESULT_MAX; i++)
+ outputMap[i] = -1;
+
+ /* look for instructions which read from varying vars */
+ for (i = 0; i < prog->NumInstructions; i++) {
+ struct prog_instruction *inst = prog->Instructions + i;
+ const GLuint numSrc = _mesa_num_inst_src_regs(inst->Opcode);
+ GLuint j;
+ for (j = 0; j < numSrc; j++) {
+ if (inst->SrcReg[j].File == PROGRAM_VARYING) {
+ /* replace the read with a temp reg */
+ const GLuint var = inst->SrcReg[j].Index;
+ if (outputMap[var] == -1) {
+ numVaryingReads++;
+ outputMap[var] = _mesa_find_free_register(prog,
+ PROGRAM_TEMPORARY);
+ }
+ inst->SrcReg[j].File = PROGRAM_TEMPORARY;
+ inst->SrcReg[j].Index = outputMap[var];
+ }
+ }
+ }
+
+ if (numVaryingReads == 0)
+ return; /* nothing to be done */
+
+ /* look for instructions which write to the varying vars identified above */
+ for (i = 0; i < prog->NumInstructions; i++) {
+ struct prog_instruction *inst = prog->Instructions + i;
+ const GLuint numSrc = _mesa_num_inst_src_regs(inst->Opcode);
+ GLuint j;
+ for (j = 0; j < numSrc; j++) {
+ if (inst->DstReg.File == PROGRAM_VARYING &&
+ outputMap[inst->DstReg.Index] >= 0) {
+ /* change inst to write to the temp reg, instead of the varying */
+ inst->DstReg.File = PROGRAM_TEMPORARY;
+ inst->DstReg.Index = outputMap[inst->DstReg.Index];
+ }
+ }
+ }
+
+ /* insert new instructions to copy the temp vars to the varying vars */
+ {
+ struct prog_instruction *inst;
+ GLint endPos, var;
+
+ /* Look for END instruction and insert the new varying writes */
+ endPos = -1;
+ for (i = 0; i < prog->NumInstructions; i++) {
+ struct prog_instruction *inst = prog->Instructions + i;
+ if (inst->Opcode == OPCODE_END) {
+ endPos = i;
+ _mesa_insert_instructions(prog, i, numVaryingReads);
+ break;
+ }
+ }
+
+ assert(endPos >= 0);
+
+ /* insert new MOV instructions here */
+ inst = prog->Instructions + endPos;
+ for (var = 0; var < VERT_RESULT_MAX; var++) {
+ if (outputMap[var] >= 0) {
+ /* MOV VAR[var], TEMP[tmp]; */
+ inst->Opcode = OPCODE_MOV;
+ inst->DstReg.File = PROGRAM_VARYING;
+ inst->DstReg.Index = var;
+ inst->SrcReg[0].File = PROGRAM_TEMPORARY;
+ inst->SrcReg[0].Index = outputMap[var];
+ inst++;
+ }
+ }
+ }
+}