1 files changed, 11 insertions, 878 deletions

diff --git a/src/mesa/drivers/dri/r300/compiler/radeon_program_pair.c b/src/mesa/drivers/dri/r300/compiler/radeon_program_pair.c
index 0d8d8e0b3b..ee839596aa 100644
--- a/src/mesa/drivers/dri/r300/compiler/radeon_program_pair.c
+++ b/src/mesa/drivers/dri/r300/compiler/radeon_program_pair.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2008 Nicolai Haehnle.
+ * Copyright (C) 2008-2009 Nicolai Haehnle.
  *
  * All Rights Reserved.
  *
@@ -25,581 +25,29 @@
  *
  */
 
-/**
- * @file
- *
- * Perform temporary register allocation and attempt to pair off instructions
- * in RGB and Alpha pairs. Also attempts to optimize the TEX instruction
- * vs. ALU instruction scheduling.
- */
-
 #include "radeon_program_pair.h"
 
-#include <stdio.h>
-
-#include "memory_pool.h"
-#include "radeon_compiler.h"
-
-#define error(fmt, args...) do { \
-	rc_error(&s->Compiler->Base, "%s::%s(): " fmt "\n",	\
-		__FILE__, __FUNCTION__, ##args);	\
-} while(0)
-
-struct pair_state_instruction {
-	struct rc_sub_instruction Instruction;
-	unsigned int IP; /**< Position of this instruction in original program */
-
-	unsigned int IsTex:1; /**< Is a texture instruction */
-	unsigned int NeedRGB:1; /**< Needs the RGB ALU */
-	unsigned int NeedAlpha:1; /**< Needs the Alpha ALU */
-	unsigned int IsTranscendent:1; /**< Is a special transcendent instruction */
-
-	/**
-	 * Number of (read and write) dependencies that must be resolved before
-	 * this instruction can be scheduled.
-	 */
-	unsigned int NumDependencies:5;
-
-	/**
-	 * Next instruction in the linked list of ready instructions.
-	 */
-	struct pair_state_instruction *NextReady;
-
-	/**
-	 * Values that this instruction writes
-	 */
-	struct reg_value *Values[4];
-};
-
-
-/**
- * Used to keep track of which instructions read a value.
- */
-struct reg_value_reader {
-	struct pair_state_instruction *Reader;
-	struct reg_value_reader *Next;
-};
-
-/**
- * Used to keep track which values are stored in each component of a
- * RC_FILE_TEMPORARY.
- */
-struct reg_value {
-	struct pair_state_instruction *Writer;
-	struct reg_value *Next; /**< Pointer to the next value to be written to the same RC_FILE_TEMPORARY component */
-
-	/**
-	 * Unordered linked list of instructions that read from this value.
-	 */
-	struct reg_value_reader *Readers;
-
-	/**
-	 * Number of readers of this value. This is calculated during @ref scan_instructions
-	 * and continually decremented during code emission.
-	 * When this count reaches zero, the instruction that writes the @ref Next value
-	 * can be scheduled.
-	 */
-	unsigned int NumReaders;
-};
-
-/**
- * Used to translate a RC_FILE_INPUT or RC_FILE_TEMPORARY Mesa register
- * to the proper hardware temporary.
- */
-struct pair_register_translation {
-	unsigned int Allocated:1;
-	unsigned int HwIndex:8;
-	unsigned int RefCount:23; /**< # of times this occurs in an unscheduled instruction SrcReg or DstReg */
-
-	/**
-	 * Notes the value that is currently contained in each component
-	 * (only used for RC_FILE_TEMPORARY registers).
-	 */
-	struct reg_value *Value[4];
-};
-
-struct pair_state {
-	struct r300_fragment_program_compiler * Compiler;
-	const struct radeon_pair_handler *Handler;
-	unsigned int Verbose;
-	void *UserData;
-
-	/**
-	 * Translate Mesa registers to hardware registers
-	 */
-	struct pair_register_translation Inputs[RC_REGISTER_MAX_INDEX];
-	struct pair_register_translation Temps[RC_REGISTER_MAX_INDEX];
-
-	struct {
-		unsigned int RefCount; /**< # of times this occurs in an unscheduled SrcReg or DstReg */
-	} HwTemps[128];
-
-	/**
-	 * Linked list of instructions that can be scheduled right now,
-	 * based on which ALU/TEX resources they require.
-	 */
-	struct pair_state_instruction *ReadyFullALU;
-	struct pair_state_instruction *ReadyRGB;
-	struct pair_state_instruction *ReadyAlpha;
-	struct pair_state_instruction *ReadyTEX;
-};
-
-
-static struct pair_register_translation *get_register(struct pair_state *s, rc_register_file file, unsigned int index)
-{
-	switch(file) {
-	case RC_FILE_TEMPORARY: return &s->Temps[index];
-	case RC_FILE_INPUT: return &s->Inputs[index];
-	default: return 0;
-	}
-}
-
-static void alloc_hw_reg(struct pair_state *s, rc_register_file file, unsigned int index, unsigned int hwindex)
-{
-	struct pair_register_translation *t = get_register(s, file, index);
-	assert(!s->HwTemps[hwindex].RefCount);
-	assert(!t->Allocated);
-	s->HwTemps[hwindex].RefCount = t->RefCount;
-	t->Allocated = 1;
-	t->HwIndex = hwindex;
-}
-
-static unsigned int get_hw_reg(struct pair_state *s, rc_register_file file, unsigned int index)
-{
-	unsigned int hwindex;
-
-	struct pair_register_translation *t = get_register(s, file, index);
-	if (!t) {
-		error("get_hw_reg: %i[%i]\n", file, index);
-		return 0;
-	}
-
-	if (t->Allocated)
-		return t->HwIndex;
-
-	for(hwindex = 0; hwindex < s->Handler->MaxHwTemps; ++hwindex)
-		if (!s->HwTemps[hwindex].RefCount)
-			break;
-
-	if (hwindex >= s->Handler->MaxHwTemps) {
-		error("Ran out of hardware temporaries");
-		return 0;
-	}
-
-	alloc_hw_reg(s, file, index, hwindex);
-	return hwindex;
-}
-
-
-static void deref_hw_reg(struct pair_state *s, unsigned int hwindex)
-{
-	if (!s->HwTemps[hwindex].RefCount) {
-		error("Hwindex %i refcount error", hwindex);
-		return;
-	}
-
-	s->HwTemps[hwindex].RefCount--;
-}
-
-static void add_pairinst_to_list(struct pair_state_instruction **list, struct pair_state_instruction *pairinst)
-{
-	pairinst->NextReady = *list;
-	*list = pairinst;
-}
-
-/**
- * The given instruction has become ready. Link it into the ready
- * instructions.
- */
-static void instruction_ready(struct pair_state *s, struct pair_state_instruction *pairinst)
-{
-	if (s->Verbose)
-		fprintf(stderr, "instruction_ready(%i)\n", pairinst->IP);
-
-	if (pairinst->IsTex)
-		add_pairinst_to_list(&s->ReadyTEX, pairinst);
-	else if (!pairinst->NeedAlpha)
-		add_pairinst_to_list(&s->ReadyRGB, pairinst);
-	else if (!pairinst->NeedRGB)
-		add_pairinst_to_list(&s->ReadyAlpha, pairinst);
-	else
-		add_pairinst_to_list(&s->ReadyFullALU, pairinst);
-}
-
-
-/**
- * Finally rewrite ADD, MOV, MUL as the appropriate native instruction
- * and reverse the order of arguments for CMP.
- */
-static void final_rewrite(struct pair_state *s, struct rc_sub_instruction *inst)
-{
-	struct rc_src_register tmp;
-
-	switch(inst->Opcode) {
-	case RC_OPCODE_ADD:
-		inst->SrcReg[2] = inst->SrcReg[1];
-		inst->SrcReg[1].File = RC_FILE_NONE;
-		inst->SrcReg[1].Swizzle = RC_SWIZZLE_1111;
-		inst->SrcReg[1].Negate = RC_MASK_NONE;
-		inst->Opcode = RC_OPCODE_MAD;
-		break;
-	case RC_OPCODE_CMP:
-		tmp = inst->SrcReg[2];
-		inst->SrcReg[2] = inst->SrcReg[0];
-		inst->SrcReg[0] = tmp;
-		break;
-	case RC_OPCODE_MOV:
-		/* AMD say we should use CMP.
-		 * However, when we transform
-		 *  KIL -r0;
-		 * into
-		 *  CMP tmp, -r0, -r0, 0;
-		 *  KIL tmp;
-		 * we get incorrect behaviour on R500 when r0 == 0.0.
-		 * It appears that the R500 KIL hardware treats -0.0 as less
-		 * than zero.
-		 */
-		inst->SrcReg[1].File = RC_FILE_NONE;
-		inst->SrcReg[1].Swizzle = RC_SWIZZLE_1111;
-		inst->SrcReg[2].File = RC_FILE_NONE;
-		inst->SrcReg[2].Swizzle = RC_SWIZZLE_0000;
-		inst->Opcode = RC_OPCODE_MAD;
-		break;
-	case RC_OPCODE_MUL:
-		inst->SrcReg[2].File = RC_FILE_NONE;
-		inst->SrcReg[2].Swizzle = RC_SWIZZLE_0000;
-		inst->Opcode = RC_OPCODE_MAD;
-		break;
-	default:
-		/* nothing to do */
-		break;
-	}
-}
-
-
-/**
- * Classify an instruction according to which ALUs etc. it needs
- */
-static void classify_instruction(struct pair_state *s,
-	struct pair_state_instruction *psi)
-{
-	psi->NeedRGB = (psi->Instruction.DstReg.WriteMask & RC_MASK_XYZ) ? 1 : 0;
-	psi->NeedAlpha = (psi->Instruction.DstReg.WriteMask & RC_MASK_W) ? 1 : 0;
-
-	switch(psi->Instruction.Opcode) {
-	case RC_OPCODE_ADD:
-	case RC_OPCODE_CMP:
-	case RC_OPCODE_DDX:
-	case RC_OPCODE_DDY:
-	case RC_OPCODE_FRC:
-	case RC_OPCODE_MAD:
-	case RC_OPCODE_MAX:
-	case RC_OPCODE_MIN:
-	case RC_OPCODE_MOV:
-	case RC_OPCODE_MUL:
-		break;
-	case RC_OPCODE_COS:
-	case RC_OPCODE_EX2:
-	case RC_OPCODE_LG2:
-	case RC_OPCODE_RCP:
-	case RC_OPCODE_RSQ:
-	case RC_OPCODE_SIN:
-		psi->IsTranscendent = 1;
-		psi->NeedAlpha = 1;
-		break;
-	case RC_OPCODE_DP4:
-		psi->NeedAlpha = 1;
-		/* fall through */
-	case RC_OPCODE_DP3:
-		psi->NeedRGB = 1;
-		break;
-	case RC_OPCODE_KIL:
-	case RC_OPCODE_TEX:
-	case RC_OPCODE_TXB:
-	case RC_OPCODE_TXP:
-		psi->IsTex = 1;
-		break;
-	default:
-		error("Unknown opcode %d\n", psi->Instruction.Opcode);
-		break;
-	}
-}
-
-
-/**
- * Count which (input, temporary) register is read and written how often,
- * and scan the instruction stream to find dependencies.
- */
-static void scan_instructions(struct pair_state *s)
-{
-	struct rc_instruction *source;
-	unsigned int ip;
-
-	for(source = s->Compiler->Base.Program.Instructions.Next, ip = 0;
-	    source != &s->Compiler->Base.Program.Instructions;
-	    source = source->Next, ++ip) {
-		struct pair_state_instruction *pairinst = memory_pool_malloc(&s->Compiler->Base.Pool, sizeof(*pairinst));
-		memset(pairinst, 0, sizeof(struct pair_state_instruction));
-
-		pairinst->Instruction = source->U.I;
-		pairinst->IP = ip;
-		final_rewrite(s, &pairinst->Instruction);
-		classify_instruction(s, pairinst);
-
-		const struct rc_opcode_info * opcode = rc_get_opcode_info(pairinst->Instruction.Opcode);
-		int j;
-		for(j = 0; j < opcode->NumSrcRegs; j++) {
-			struct pair_register_translation *t =
-				get_register(s, pairinst->Instruction.SrcReg[j].File, pairinst->Instruction.SrcReg[j].Index);
-			if (!t)
-				continue;
-
-			t->RefCount++;
-
-			if (pairinst->Instruction.SrcReg[j].File == RC_FILE_TEMPORARY) {
-				int i;
-				for(i = 0; i < 4; ++i) {
-					unsigned int swz = GET_SWZ(pairinst->Instruction.SrcReg[j].Swizzle, i);
-					if (swz >= 4)
-						continue; /* constant or NIL swizzle */
-					if (!t->Value[swz])
-						continue; /* this is an undefined read */
-
-					/* Do not add a dependency if this instruction
-					 * also rewrites the value. The code below adds
-					 * a dependency for the DstReg, which is a superset
-					 * of the SrcReg dependency. */
-					if (pairinst->Instruction.DstReg.File == RC_FILE_TEMPORARY &&
-					    pairinst->Instruction.DstReg.Index == pairinst->Instruction.SrcReg[j].Index &&
-					    GET_BIT(pairinst->Instruction.DstReg.WriteMask, swz))
-						continue;
-
-					struct reg_value_reader* r = memory_pool_malloc(&s->Compiler->Base.Pool, sizeof(*r));
-					pairinst->NumDependencies++;
-					t->Value[swz]->NumReaders++;
-					r->Reader = pairinst;
-					r->Next = t->Value[swz]->Readers;
-					t->Value[swz]->Readers = r;
-				}
-			}
-		}
-
-		if (opcode->HasDstReg) {
-			struct pair_register_translation *t =
-				get_register(s, pairinst->Instruction.DstReg.File, pairinst->Instruction.DstReg.Index);
-			if (t) {
-				t->RefCount++;
-
-				if (pairinst->Instruction.DstReg.File == RC_FILE_TEMPORARY) {
-					int j;
-					for(j = 0; j < 4; ++j) {
-						if (!GET_BIT(pairinst->Instruction.DstReg.WriteMask, j))
-							continue;
-
-						struct reg_value* v = memory_pool_malloc(&s->Compiler->Base.Pool, sizeof(*v));
-						memset(v, 0, sizeof(struct reg_value));
-						v->Writer = pairinst;
-						if (t->Value[j]) {
-							pairinst->NumDependencies++;
-							t->Value[j]->Next = v;
-						}
-						t->Value[j] = v;
-						pairinst->Values[j] = v;
-					}
-				}
-			}
-		}
-
-		if (s->Verbose)
-			fprintf(stderr, "scan(%i): NumDeps = %i\n", ip, pairinst->NumDependencies);
-
-		if (!pairinst->NumDependencies)
-			instruction_ready(s, pairinst);
-	}
-
-	/* Clear the RC_FILE_TEMPORARY state */
-	int i, j;
-	for(i = 0; i < RC_REGISTER_MAX_INDEX; ++i) {
-		for(j = 0; j < 4; ++j)
-			s->Temps[i].Value[j] = 0;
-	}
-}
-
-
-static void decrement_dependencies(struct pair_state *s, struct pair_state_instruction *pairinst)
-{
-	assert(pairinst->NumDependencies > 0);
-	if (!--pairinst->NumDependencies)
-		instruction_ready(s, pairinst);
-}
 
 /**
- * Update the dependency tracking state based on what the instruction
- * at the given IP does.
+ * Return the source slot where we installed the given register access,
+ * or -1 if no slot was free anymore.
  */
-static void commit_instruction(struct pair_state *s, struct pair_state_instruction *pairinst)
-{
-	struct rc_sub_instruction *inst = &pairinst->Instruction;
-
-	if (s->Verbose)
-		fprintf(stderr, "commit_instruction(%i)\n", pairinst->IP);
-
-	if (inst->DstReg.File == RC_FILE_TEMPORARY) {
-		struct pair_register_translation *t = &s->Temps[inst->DstReg.Index];
-		deref_hw_reg(s, t->HwIndex);
-
-		int i;
-		for(i = 0; i < 4; ++i) {
-			if (!GET_BIT(inst->DstReg.WriteMask, i))
-				continue;
-
-			t->Value[i] = pairinst->Values[i];
-			if (t->Value[i]->NumReaders) {
-				struct reg_value_reader *r;
-				for(r = pairinst->Values[i]->Readers; r; r = r->Next)
-					decrement_dependencies(s, r->Reader);
-			} else if (t->Value[i]->Next) {
-				/* This happens when the only reader writes
-				 * the register at the same time */
-				decrement_dependencies(s, t->Value[i]->Next->Writer);
-			}
-		}
-	}
-
-	const struct rc_opcode_info * opcode = rc_get_opcode_info(inst->Opcode);
-	int i;
-	for(i = 0; i < opcode->NumSrcRegs; i++) {
-		struct pair_register_translation *t = get_register(s, inst->SrcReg[i].File, inst->SrcReg[i].Index);
-		if (!t)
-			continue;
-
-		deref_hw_reg(s, get_hw_reg(s, inst->SrcReg[i].File, inst->SrcReg[i].Index));
-
-		if (inst->SrcReg[i].File != RC_FILE_TEMPORARY)
-			continue;
-
-		int j;
-		for(j = 0; j < 4; ++j) {
-			unsigned int swz = GET_SWZ(inst->SrcReg[i].Swizzle, j);
-			if (swz >= 4)
-				continue;
-			if (!t->Value[swz])
-				continue;
-
-			/* Do not free a dependency if this instruction
-			 * also rewrites the value. See scan_instructions. */
-			if (inst->DstReg.File == RC_FILE_TEMPORARY &&
-			    inst->DstReg.Index == inst->SrcReg[i].Index &&
-			    GET_BIT(inst->DstReg.WriteMask, swz))
-				continue;
-
-			if (!--t->Value[swz]->NumReaders) {
-				if (t->Value[swz]->Next)
-					decrement_dependencies(s, t->Value[swz]->Next->Writer);
-			}
-		}
-	}
-}
-
-
-/**
- * Emit all ready texture instructions in a single block.
- *
- * Emit as a single block to (hopefully) sample many textures in parallel,
- * and to avoid hardware indirections on R300.
- *
- * In R500, we don't really know when the result of a texture instruction
- * arrives. So allocate all destinations first, to make sure they do not
- * arrive early and overwrite a texture coordinate we're going to use later
- * in the block.
- */
-static void emit_all_tex(struct pair_state *s)
-{
-	struct pair_state_instruction *readytex;
-	struct pair_state_instruction *pairinst;
-
-	assert(s->ReadyTEX);
-
-	// Don't let the ready list change under us!
-	readytex = s->ReadyTEX;
-	s->ReadyTEX = 0;
-
-	// Allocate destination hardware registers in one block to avoid conflicts.
-	for(pairinst = readytex; pairinst; pairinst = pairinst->NextReady) {
-		struct rc_sub_instruction *inst = &pairinst->Instruction;
-		if (inst->Opcode != RC_OPCODE_KIL)
-			get_hw_reg(s, inst->DstReg.File, inst->DstReg.Index);
-	}
-
-	if (s->Compiler->Base.Debug)
-		fprintf(stderr, " BEGIN_TEX\n");
-
-	if (s->Handler->BeginTexBlock)
-		s->Compiler->Base.Error = s->Compiler->Base.Error || !s->Handler->BeginTexBlock(s->UserData);
-
-	for(pairinst = readytex; pairinst; pairinst = pairinst->NextReady) {
-		struct rc_sub_instruction *inst = &pairinst->Instruction;
-		commit_instruction(s, pairinst);
-
-		if (inst->Opcode != RC_OPCODE_KIL)
-			inst->DstReg.Index = get_hw_reg(s, inst->DstReg.File, inst->DstReg.Index);
-		inst->SrcReg[0].Index = get_hw_reg(s, inst->SrcReg[0].File, inst->SrcReg[0].Index);
-
-		if (s->Compiler->Base.Debug) {
-			/* Should print the TEX instruction here */
-		}
-
-		struct radeon_pair_texture_instruction rpti;
-
-		switch(inst->Opcode) {
-		case RC_OPCODE_TEX: rpti.Opcode = RADEON_OPCODE_TEX; break;
-		case RC_OPCODE_TXB: rpti.Opcode = RADEON_OPCODE_TXB; break;
-		case RC_OPCODE_TXP: rpti.Opcode = RADEON_OPCODE_TXP; break;
-		default:
-		case RC_OPCODE_KIL: rpti.Opcode = RADEON_OPCODE_KIL; break;
-		}
-
-		rpti.DestIndex = inst->DstReg.Index;
-		rpti.WriteMask = inst->DstReg.WriteMask;
-		rpti.TexSrcUnit = inst->TexSrcUnit;
-		rpti.TexSrcTarget = inst->TexSrcTarget;
-		rpti.SrcIndex = inst->SrcReg[0].Index;
-		rpti.SrcSwizzle = inst->SrcReg[0].Swizzle;
-
-		s->Compiler->Base.Error = s->Compiler->Base.Error || !s->Handler->EmitTex(s->UserData, &rpti);
-	}
-
-	if (s->Compiler->Base.Debug)
-		fprintf(stderr, " END_TEX\n");
-}
-
-
-static int alloc_pair_source(struct pair_state *s, struct radeon_pair_instruction *pair,
-	struct rc_src_register src, unsigned int rgb, unsigned int alpha)
+int rc_pair_alloc_source(struct rc_pair_instruction *pair,
+	unsigned int rgb, unsigned int alpha,
+	rc_register_file file, unsigned int index)
 {
 	int candidate = -1;
 	int candidate_quality = -1;
 	int i;
 
-	if (!rgb && !alpha)
+	if ((!rgb && !alpha) || file == RC_FILE_NONE)
 		return 0;
 
-	unsigned int constant;
-	unsigned int index;
-
-	if (src.File == RC_FILE_TEMPORARY || src.File == RC_FILE_INPUT) {
-		constant = 0;
-		index = get_hw_reg(s, src.File, src.Index);
-	} else {
-		constant = 1;
-		index = src.Index;
-	}
-
 	for(i = 0; i < 3; ++i) {
 		int q = 0;
 		if (rgb) {
 			if (pair->RGB.Src[i].Used) {
-				if (pair->RGB.Src[i].Constant != constant ||
+				if (pair->RGB.Src[i].File != file ||
 				    pair->RGB.Src[i].Index != index)
 					continue;
 				q++;
@@ -607,7 +55,7 @@ static int alloc_pair_source(struct pair_state *s, struct radeon_pair_instructio
 		}
 		if (alpha) {
 			if (pair->Alpha.Src[i].Used) {
-				if (pair->Alpha.Src[i].Constant != constant ||
+				if (pair->Alpha.Src[i].File != file ||
 				    pair->Alpha.Src[i].Index != index)
 					continue;
 				q++;
@@ -622,330 +70,15 @@ static int alloc_pair_source(struct pair_state *s, struct radeon_pair_instructio
 	if (candidate >= 0) {
 		if (rgb) {
 			pair->RGB.Src[candidate].Used = 1;
-			pair->RGB.Src[candidate].Constant = constant;
+			pair->RGB.Src[candidate].File = file;
 			pair->RGB.Src[candidate].Index = index;
 		}
 		if (alpha) {
 			pair->Alpha.Src[candidate].Used = 1;
-			pair->Alpha.Src[candidate].Constant = constant;
+			pair->Alpha.Src[candidate].File = file;
 			pair->Alpha.Src[candidate].Index = index;
 		}
 	}
 
 	return candidate;
 }
-
-/**
- * Fill the given ALU instruction's opcodes and source operands into the given pair,
- * if possible.
- */
-static int fill_instruction_into_pair(
-	struct pair_state *s,
-	struct radeon_pair_instruction *pair,
-	struct pair_state_instruction *pairinst)
-{
-	struct rc_sub_instruction *inst = &pairinst->Instruction;
-
-	assert(!pairinst->NeedRGB || pair->RGB.Opcode == RC_OPCODE_NOP);
-	assert(!pairinst->NeedAlpha || pair->Alpha.Opcode == RC_OPCODE_NOP);
-
-	if (pairinst->NeedRGB) {
-		if (pairinst->IsTranscendent)
-			pair->RGB.Opcode = RC_OPCODE_REPL_ALPHA;
-		else
-			pair->RGB.Opcode = inst->Opcode;
-		if (inst->SaturateMode == RC_SATURATE_ZERO_ONE)
-			pair->RGB.Saturate = 1;
-	}
-	if (pairinst->NeedAlpha) {
-		pair->Alpha.Opcode = inst->Opcode;
-		if (inst->SaturateMode == RC_SATURATE_ZERO_ONE)
-			pair->Alpha.Saturate = 1;
-	}
-
-	const struct rc_opcode_info * opcode = rc_get_opcode_info(inst->Opcode);
-	int nargs = opcode->NumSrcRegs;
-	int i;
-
-	/* Special case for DDX/DDY (MDH/MDV). */
-	if (inst->Opcode == RC_OPCODE_DDX || inst->Opcode == RC_OPCODE_DDY) {
-		if (pair->RGB.Src[0].Used || pair->Alpha.Src[0].Used)
-			return 0;
-		else
-			nargs++;
-	}
-
-	for(i = 0; i < nargs; ++i) {
-		int source;
-		if (pairinst->NeedRGB && !pairinst->IsTranscendent) {
-			unsigned int srcrgb = 0;
-			unsigned int srcalpha = 0;
-			int j;
-			for(j = 0; j < 3; ++j) {
-				unsigned int swz = GET_SWZ(inst->SrcReg[i].Swizzle, j);
-				if (swz < 3)
-					srcrgb = 1;
-				else if (swz < 4)
-					srcalpha = 1;
-			}
-			source = alloc_pair_source(s, pair, inst->SrcReg[i], srcrgb, srcalpha);
-			if (source < 0)
-				return 0;
-			pair->RGB.Arg[i].Source = source;
-			pair->RGB.Arg[i].Swizzle = inst->SrcReg[i].Swizzle & 0x1ff;
-			pair->RGB.Arg[i].Abs = inst->SrcReg[i].Abs;
-			pair->RGB.Arg[i].Negate = !!(inst->SrcReg[i].Negate & (RC_MASK_X | RC_MASK_Y | RC_MASK_Z));
-		}
-		if (pairinst->NeedAlpha) {
-			unsigned int srcrgb = 0;
-			unsigned int srcalpha = 0;
-			unsigned int swz = GET_SWZ(inst->SrcReg[i].Swizzle, pairinst->IsTranscendent ? 0 : 3);
-			if (swz < 3)
-				srcrgb = 1;
-			else if (swz < 4)
-				srcalpha = 1;
-			source = alloc_pair_source(s, pair, inst->SrcReg[i], srcrgb, srcalpha);
-			if (source < 0)
-				return 0;
-			pair->Alpha.Arg[i].Source = source;
-			pair->Alpha.Arg[i].Swizzle = swz;
-			pair->Alpha.Arg[i].Abs = inst->SrcReg[i].Abs;
-			pair->Alpha.Arg[i].Negate = !!(inst->SrcReg[i].Negate & RC_MASK_W);
-		}
-	}
-
-	return 1;
-}
-
-
-/**
- * Fill in the destination register information.
- *
- * This is split from filling in source registers because we want
- * to avoid allocating hardware temporaries for destinations until
- * we are absolutely certain that we're going to emit a certain
- * instruction pairing.
- */
-static void fill_dest_into_pair(
-	struct pair_state *s,
-	struct radeon_pair_instruction *pair,
-	struct pair_state_instruction *pairinst)
-{
-	struct rc_sub_instruction *inst = &pairinst->Instruction;
-
-	if (inst->DstReg.File == RC_FILE_OUTPUT) {
-		if (inst->DstReg.Index == s->Compiler->OutputColor) {
-			pair->RGB.OutputWriteMask |= inst->DstReg.WriteMask & RC_MASK_XYZ;
-			pair->Alpha.OutputWriteMask |= GET_BIT(inst->DstReg.WriteMask, 3);
-		} else if (inst->DstReg.Index == s->Compiler->OutputDepth) {
-			pair->Alpha.DepthWriteMask |= GET_BIT(inst->DstReg.WriteMask, 3);
-		}
-	} else {
-		unsigned int hwindex = get_hw_reg(s, inst->DstReg.File, inst->DstReg.Index);
-		if (pairinst->NeedRGB) {
-			pair->RGB.DestIndex = hwindex;
-			pair->RGB.WriteMask |= inst->DstReg.WriteMask & RC_MASK_XYZ;
-		}
-		if (pairinst->NeedAlpha) {
-			pair->Alpha.DestIndex = hwindex;
-			pair->Alpha.WriteMask |= GET_BIT(inst->DstReg.WriteMask, 3);
-		}
-	}
-}
-
-
-/**
- * Find a good ALU instruction or pair of ALU instruction and emit it.
- *
- * Prefer emitting full ALU instructions, so that when we reach a point
- * where no full ALU instruction can be emitted, we have more candidates
- * for RGB/Alpha pairing.
- */
-static void emit_alu(struct pair_state *s)
-{
-	struct radeon_pair_instruction pair;
-	struct pair_state_instruction *psi;
-
-	if (s->ReadyFullALU || !(s->ReadyRGB && s->ReadyAlpha)) {
-		if (s->ReadyFullALU) {
-			psi = s->ReadyFullALU;
-			s->ReadyFullALU = s->ReadyFullALU->NextReady;
-		} else if (s->ReadyRGB) {
-			psi = s->ReadyRGB;
-			s->ReadyRGB = s->ReadyRGB->NextReady;
-		} else {
-			psi = s->ReadyAlpha;
-			s->ReadyAlpha = s->ReadyAlpha->NextReady;
-		}
-
-		memset(&pair, 0, sizeof(pair));
-		fill_instruction_into_pair(s, &pair, psi);
-		fill_dest_into_pair(s, &pair, psi);
-		commit_instruction(s, psi);
-	} else {
-		struct pair_state_instruction **prgb;
-		struct pair_state_instruction **palpha;
-
-		/* Some pairings might fail because they require too
-		 * many source slots; try all possible pairings if necessary */
-		for(prgb = &s->ReadyRGB; *prgb; prgb = &(*prgb)->NextReady) {
-			for(palpha = &s->ReadyAlpha; *palpha; palpha = &(*palpha)->NextReady) {
-				struct pair_state_instruction * psirgb = *prgb;
-				struct pair_state_instruction * psialpha = *palpha;
-				memset(&pair, 0, sizeof(pair));
-				fill_instruction_into_pair(s, &pair, psirgb);
-				if (!fill_instruction_into_pair(s, &pair, psialpha))
-					continue;
-				*prgb = (*prgb)->NextReady;
-				*palpha = (*palpha)->NextReady;
-				fill_dest_into_pair(s, &pair, psirgb);
-				fill_dest_into_pair(s, &pair, psialpha);
-				commit_instruction(s, psirgb);
-				commit_instruction(s, psialpha);
-				goto success;
-			}
-		}
-
-		/* No success in pairing; just take the first RGB instruction */
-		psi = s->ReadyRGB;
-		s->ReadyRGB = s->ReadyRGB->NextReady;
-
-		memset(&pair, 0, sizeof(pair));
-		fill_instruction_into_pair(s, &pair, psi);
-		fill_dest_into_pair(s, &pair, psi);
-		commit_instruction(s, psi);
-	success: ;
-	}
-
-	if (s->Compiler->Base.Debug)
-		radeonPrintPairInstruction(&pair);
-
-	s->Compiler->Base.Error = s->Compiler->Base.Error || !s->Handler->EmitPaired(s->UserData, &pair);
-}
-
-/* Callback function for assigning input registers to hardware registers */
-static void alloc_helper(void * data, unsigned input, unsigned hwreg)
-{
-	struct pair_state * s = data;
-	alloc_hw_reg(s, RC_FILE_INPUT, input, hwreg);
-}
-
-void radeonPairProgram(
-	struct r300_fragment_program_compiler * compiler,
-	const struct radeon_pair_handler* handler, void *userdata)
-{
-	struct pair_state s;
-
-	memset(&s, 0, sizeof(s));
-	s.Compiler = compiler;
-	s.Handler = handler;
-	s.UserData = userdata;
-	s.Verbose = 0 && s.Compiler->Base.Debug;
-
-	if (s.Compiler->Base.Debug)
-		fprintf(stderr, "Emit paired program\n");
-
-	scan_instructions(&s);
-	s.Compiler->AllocateHwInputs(s.Compiler, &alloc_helper, &s);
-
-	while(!s.Compiler->Base.Error &&
-	      (s.ReadyTEX || s.ReadyRGB || s.ReadyAlpha || s.ReadyFullALU)) {
-		if (s.ReadyTEX)
-			emit_all_tex(&s);
-
-		while(s.ReadyFullALU || s.ReadyRGB || s.ReadyAlpha)
-			emit_alu(&s);
-	}
-
-	if (s.Compiler->Base.Debug)
-		fprintf(stderr, " END\n");
-}
-
-
-static void print_pair_src(int i, struct radeon_pair_instruction_source* src)
-{
-	fprintf(stderr, "  Src%i = %s[%i]", i, src->Constant ? "CNST" : "TEMP", src->Index);
-}
-
-static const char* opcode_string(rc_opcode opcode)
-{
-	return rc_get_opcode_info(opcode)->Name;
-}
-
-static int num_pairinst_args(rc_opcode opcode)
-{
-	return rc_get_opcode_info(opcode)->NumSrcRegs;
-}
-
-static char swizzle_char(rc_swizzle swz)
-{
-	switch(swz) {
-	case RC_SWIZZLE_X: return 'x';
-	case RC_SWIZZLE_Y: return 'y';
-	case RC_SWIZZLE_Z: return 'z';
-	case RC_SWIZZLE_W: return 'w';
-	case RC_SWIZZLE_ZERO: return '0';
-	case RC_SWIZZLE_ONE: return '1';
-	case RC_SWIZZLE_HALF: return 'H';
-	case RC_SWIZZLE_UNUSED: return '_';
-	default: return '?';
-	}
-}
-
-void radeonPrintPairInstruction(struct radeon_pair_instruction *inst)
-{
-	int nargs;
-	int i;
-
-	fprintf(stderr, "       RGB:  ");
-	for(i = 0; i < 3; ++i) {
-		if (inst->RGB.Src[i].Used)
-			print_pair_src(i, inst->RGB.Src + i);
-	}
-	fprintf(stderr, "\n");
-	fprintf(stderr, "       Alpha:");
-	for(i = 0; i < 3; ++i) {
-		if (inst->Alpha.Src[i].Used)
-			print_pair_src(i, inst->Alpha.Src + i);
-	}
-	fprintf(stderr, "\n");
-
-	fprintf(stderr, "  %s%s", opcode_string(inst->RGB.Opcode), inst->RGB.Saturate ? "_SAT" : "");
-	if (inst->RGB.WriteMask)
-		fprintf(stderr, " TEMP[%i].%s%s%s", inst->RGB.DestIndex,
-			(inst->RGB.WriteMask & 1) ? "x" : "",
-			(inst->RGB.WriteMask & 2) ? "y" : "",
-			(inst->RGB.WriteMask & 4) ? "z" : "");
-	if (inst->RGB.OutputWriteMask)
-		fprintf(stderr, " COLOR.%s%s%s",
-			(inst->RGB.OutputWriteMask & 1) ? "x" : "",
-			(inst->RGB.OutputWriteMask & 2) ? "y" : "",
-			(inst->RGB.OutputWriteMask & 4) ? "z" : "");
-	nargs = num_pairinst_args(inst->RGB.Opcode);
-	for(i = 0; i < nargs; ++i) {
-		const char* abs = inst->RGB.Arg[i].Abs ? "|" : "";
-		const char* neg = inst->RGB.Arg[i].Negate ? "-" : "";
-		fprintf(stderr, ", %s%sSrc%i.%c%c%c%s", neg, abs, inst->RGB.Arg[i].Source,
-			swizzle_char(GET_SWZ(inst->RGB.Arg[i].Swizzle, 0)),
-			swizzle_char(GET_SWZ(inst->RGB.Arg[i].Swizzle, 1)),
-			swizzle_char(GET_SWZ(inst->RGB.Arg[i].Swizzle, 2)),
-			abs);
-	}
-	fprintf(stderr, "\n");
-
-	fprintf(stderr, "  %s%s", opcode_string(inst->Alpha.Opcode), inst->Alpha.Saturate ? "_SAT" : "");
-	if (inst->Alpha.WriteMask)
-		fprintf(stderr, " TEMP[%i].w", inst->Alpha.DestIndex);
-	if (inst->Alpha.OutputWriteMask)
-		fprintf(stderr, " COLOR.w");
-	if (inst->Alpha.DepthWriteMask)
-		fprintf(stderr, " DEPTH.w");
-	nargs = num_pairinst_args(inst->Alpha.Opcode);
-	for(i = 0; i < nargs; ++i) {
-		const char* abs = inst->Alpha.Arg[i].Abs ? "|" : "";
-		const char* neg = inst->Alpha.Arg[i].Negate ? "-" : "";
-		fprintf(stderr, ", %s%sSrc%i.%c%s", neg, abs, inst->Alpha.Arg[i].Source,
-			swizzle_char(inst->Alpha.Arg[i].Swizzle), abs);
-	}
-	fprintf(stderr, "\n");
-}