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authorBrian <[email protected]>2007-03-28 11:06:34 -0600
committerBrian <[email protected]>2007-03-28 11:06:34 -0600
commitdad97b4688ea25caf15cae66194db6ddbb98e936 (patch)
treec285c5d3b7d6fa43247e649739b8a14fbe9fc294 /src/mesa/shader/slang/slang_emit.c
parenta01616eed52aa4dfe3b6850b76a4cd8de119a3f3 (diff)
Fix, clean-up code related to comparisons, condition codes, etc.
Diffstat (limited to 'src/mesa/shader/slang/slang_emit.c')
-rw-r--r--src/mesa/shader/slang/slang_emit.c125
1 files changed, 78 insertions, 47 deletions
diff --git a/src/mesa/shader/slang/slang_emit.c b/src/mesa/shader/slang/slang_emit.c
index 64163c4959e..cbc71f36f6b 100644
--- a/src/mesa/shader/slang/slang_emit.c
+++ b/src/mesa/shader/slang/slang_emit.c
@@ -86,6 +86,25 @@ new_subroutine(slang_emit_info *emitInfo, GLuint *id)
}
+/**
+ * Convert a writemask to a swizzle. Used for testing cond codes because
+ * we only want to test the cond code component(s) that was set by the
+ * previous instruction.
+ */
+static GLuint
+writemask_to_swizzle(GLuint writemask)
+{
+ if (writemask == WRITEMASK_X)
+ return SWIZZLE_XXXX;
+ if (writemask == WRITEMASK_Y)
+ return SWIZZLE_YYYY;
+ if (writemask == WRITEMASK_Z)
+ return SWIZZLE_ZZZZ;
+ if (writemask == WRITEMASK_W)
+ return SWIZZLE_WWWW;
+ return SWIZZLE_XYZW; /* shouldn't be hit */
+}
+
/**
* Swizzle a swizzle. That is, return swz2(swz1)
@@ -152,6 +171,8 @@ free_temp_storage(slang_var_table *vt, slang_ir_node *n)
_slang_free_temp(vt, n->Store);
n->Store->Index = -1;
n->Store->Size = -1;
+ _mesa_free(n->Store);
+ n->Store = NULL;
}
}
}
@@ -485,6 +506,7 @@ emit_arith(slang_emit_info *emitInfo, slang_ir_node *n)
/* result storage */
if (!n->Store) {
+ /* XXX this size isn't correct, it depends on the operands */
if (!alloc_temp_storage(emitInfo, n, info->ResultSize))
return NULL;
}
@@ -542,8 +564,9 @@ emit_compare(slang_emit_info *emitInfo, slang_ir_node *n)
assert(zeroReg >= 0);
+ assert(!n->Store);
if (!n->Store) {
- if (!alloc_temp_storage(emitInfo, n, 4)) /* 4 bools */
+ if (!alloc_temp_storage(emitInfo, n, size)) /* 'size' bools */
return NULL;
}
@@ -561,34 +584,32 @@ emit_compare(slang_emit_info *emitInfo, slang_ir_node *n)
swizzle = MAKE_SWIZZLE4(SWIZZLE_X, SWIZZLE_Y, SWIZZLE_Y, SWIZZLE_Y);
}
- /* Compute equality, inequality */
+ /* Compute equality, inequality (tmp1 = (A ?= B)) */
inst = new_instruction(emitInfo, OPCODE_SNE);
storage_to_src_reg(&inst->SrcReg[0], n->Children[0]->Store);
storage_to_src_reg(&inst->SrcReg[1], n->Children[1]->Store);
storage_to_dst_reg(&inst->DstReg, n->Store, n->Writemask);
inst->Comment = _mesa_strdup("Compare values");
- /* compute D = DP4(D, D) (reduction) */
+
+ /* Compute tmp2 = DOT(tmp1, tmp1) (reduction) */
inst = new_instruction(emitInfo, dotOp);
- inst->SrcReg[0].File = PROGRAM_TEMPORARY;
- inst->SrcReg[0].Index = n->Store->Index;
- inst->SrcReg[0].Swizzle = swizzle;
- inst->SrcReg[1].File = PROGRAM_TEMPORARY;
- inst->SrcReg[1].Index = n->Store->Index;
- inst->SrcReg[1].Swizzle = swizzle;
- inst->DstReg.File = PROGRAM_TEMPORARY;
- inst->DstReg.Index = n->Store->Index;
+ storage_to_src_reg(&inst->SrcReg[0], n->Store);
+ storage_to_src_reg(&inst->SrcReg[1], n->Store);
+ inst->SrcReg[0].Swizzle = inst->SrcReg[1].Swizzle = swizzle; /*override*/
+ free_temp_storage(emitInfo->vt, n); /* free tmp1 */
+ if (!alloc_temp_storage(emitInfo, n, 1)) /* alloc tmp2 */
+ return NULL;
+ storage_to_dst_reg(&inst->DstReg, n->Store, n->Writemask);
inst->Comment = _mesa_strdup("Reduce vec to bool");
+
if (n->Opcode == IR_EQUAL) {
- /* compute D.x = !D.x via D.x = (D.x == 0) */
+ /* compute tmp2.x = !tmp2.x via tmp2.x = (tmp2.x == 0) */
inst = new_instruction(emitInfo, OPCODE_SEQ);
- inst->SrcReg[0].File = PROGRAM_TEMPORARY;
- inst->SrcReg[0].Index = n->Store->Index;
+ storage_to_src_reg(&inst->SrcReg[0], n->Store);
inst->SrcReg[1].File = PROGRAM_CONSTANT;
inst->SrcReg[1].Index = zeroReg;
inst->SrcReg[1].Swizzle = zeroSwizzle;
- inst->DstReg.File = PROGRAM_TEMPORARY;
- inst->DstReg.Index = n->Store->Index;
- inst->DstReg.WriteMask = WRITEMASK_X;
+ storage_to_dst_reg(&inst->DstReg, n->Store, n->Writemask);
inst->Comment = _mesa_strdup("Invert true/false");
}
}
@@ -757,6 +778,11 @@ emit_func(slang_emit_info *emitInfo, slang_ir_node *n)
emitInfo->prog);
if (emitInfo->EmitBeginEndSub) {
+ /* BGNSUB isn't a real instruction.
+ * We require a label (i.e. "foobar:") though, if we're going to
+ * print the program in the NV format. The BNGSUB instruction is
+ * really just a NOP to attach the label to.
+ */
inst = new_instruction(emitInfo, OPCODE_BGNSUB);
inst->Comment = _mesa_strdup(n->Label->Name);
}
@@ -800,17 +826,8 @@ emit_return(slang_emit_info *emitInfo, slang_ir_node *n)
assert(n);
assert(n->Opcode == IR_RETURN);
assert(n->Label);
- inst = new_instruction(emitInfo, OPCODE_RET/*BRA*/); /*XXX TEMPORARY*/
- inst->DstReg.CondMask = COND_TR; /* always return/branch */
-
- if (inst->Opcode == OPCODE_BRA) {
- inst->BranchTarget = _slang_label_get_location(n->Label);
- if (inst->BranchTarget < 0) {
- _slang_label_add_reference(n->Label,
- emitInfo->prog->NumInstructions - 1);
- }
- }
-
+ inst = new_instruction(emitInfo, OPCODE_RET);
+ inst->DstReg.CondMask = COND_TR; /* always return */
return inst;
}
@@ -949,28 +966,34 @@ emit_move(slang_emit_info *emitInfo, slang_ir_node *n)
}
+/**
+ * An IR_COND node wraps a boolean expression which is used by an
+ * IF or WHILE test. This is where we'll set condition codes, if needed.
+ */
static struct prog_instruction *
emit_cond(slang_emit_info *emitInfo, slang_ir_node *n)
{
struct prog_instruction *inst;
+ assert(n->Opcode == IR_COND);
+
if (!n->Children[0])
return NULL;
+ /* emit code for the expression */
inst = emit(emitInfo, n->Children[0]);
+ assert(n->Children[0]->Store);
+ /*assert(n->Children[0]->Store->Size == 1);*/
+
if (emitInfo->EmitCondCodes) {
- /* Conditional expression (in if/while/for stmts).
- * Need to update condition code register.
- * Next instruction is typically an IR_IF.
- */
if (inst &&
n->Children[0]->Store &&
inst->DstReg.File == n->Children[0]->Store->File &&
inst->DstReg.Index == n->Children[0]->Store->Index) {
/* The previous instruction wrote to the register who's value
- * we're testing. Just update that instruction so that the
- * condition codes are updated.
+ * we're testing. Just fix that instruction so that the
+ * condition codes are computed.
*/
inst->CondUpdate = GL_TRUE;
n->Store = n->Children[0]->Store;
@@ -980,10 +1003,8 @@ emit_cond(slang_emit_info *emitInfo, slang_ir_node *n)
/* This'll happen for things like "if (i) ..." where no code
* is normally generated for the expression "i".
* Generate a move instruction just to set condition codes.
- * Note: must use full 4-component vector since all four
- * condition codes must be set identically.
*/
- if (!alloc_temp_storage(emitInfo, n, 4))
+ if (!alloc_temp_storage(emitInfo, n, 1))
return NULL;
inst = new_instruction(emitInfo, OPCODE_MOV);
inst->CondUpdate = GL_TRUE;
@@ -991,13 +1012,13 @@ emit_cond(slang_emit_info *emitInfo, slang_ir_node *n)
storage_to_src_reg(&inst->SrcReg[0], n->Children[0]->Store);
_slang_free_temp(emitInfo->vt, n->Store);
inst->Comment = _mesa_strdup("COND expr");
- return inst; /* XXX or null? */
+ return inst;
}
}
else {
- /* No-op */
+ /* No-op: the boolean result of the expression is in a regular reg */
n->Store = n->Children[0]->Store;
- return NULL;
+ return inst;
}
}
@@ -1042,10 +1063,15 @@ static struct prog_instruction *
emit_if(slang_emit_info *emitInfo, slang_ir_node *n)
{
struct gl_program *prog = emitInfo->prog;
- struct prog_instruction *ifInst;
+ struct prog_instruction *ifInst, *inst;
GLuint ifInstLoc, elseInstLoc = 0;
+ GLuint condWritemask = 0;
- emit(emitInfo, n->Children[0]); /* the condition */
+ inst = emit(emitInfo, n->Children[0]); /* the condition */
+ if (emitInfo->EmitCondCodes) {
+ assert(inst);
+ condWritemask = inst->DstReg.WriteMask;
+ }
#if 0
assert(n->Children[0]->Store->Size == 1); /* a bool! */
@@ -1056,6 +1082,10 @@ emit_if(slang_emit_info *emitInfo, slang_ir_node *n)
ifInst = new_instruction(emitInfo, OPCODE_IF);
if (emitInfo->EmitCondCodes) {
ifInst->DstReg.CondMask = COND_NE; /* if cond is non-zero */
+ /* only test the cond code (1 of 4) that was updated by the
+ * previous instruction.
+ */
+ ifInst->DstReg.CondSwizzle = writemask_to_swizzle(condWritemask);
}
else {
/* test reg.x */
@@ -1067,10 +1097,7 @@ emit_if(slang_emit_info *emitInfo, slang_ir_node *n)
ifInst = new_instruction(emitInfo, OPCODE_BRA);
ifInst->DstReg.CondMask = COND_EQ; /* BRA if cond is zero */
ifInst->Comment = _mesa_strdup("if zero");
- }
- if (emitInfo->EmitCondCodes) {
- /* which condition code to use: */
- ifInst->DstReg.CondSwizzle = n->Children[0]->Store->Swizzle;
+ ifInst->DstReg.CondSwizzle = writemask_to_swizzle(condWritemask);
}
/* if body */
@@ -1097,7 +1124,7 @@ emit_if(slang_emit_info *emitInfo, slang_ir_node *n)
else {
/* no else body */
ifInst = prog->Instructions + ifInstLoc;
- ifInst->BranchTarget = prog->NumInstructions + 1;
+ ifInst->BranchTarget = prog->NumInstructions /*+ 1*/;
}
if (emitInfo->EmitHighLevelInstructions) {
@@ -1736,6 +1763,10 @@ _slang_emit_code(slang_ir_node *n, slang_var_table *vt,
emitInfo.EmitComments = ctx->Shader.EmitComments;
emitInfo.EmitBeginEndSub = 0; /* XXX for compiler debug only */
+ if (!emitInfo.EmitCondCodes) {
+ emitInfo.EmitHighLevelInstructions = GL_TRUE;
+ }
+
(void) emit(&emitInfo, n);
/* finish up by adding the END opcode to program */