gallium: Copy fd_lowering.[ch] to tgsi_lowering.[ch] for code sharing.

Lots of drivers need to transform the weird instructions in TGSI into
reasonable scalar ops, and this code can make those translations
canonical.

Acked-by: Rob Clark <[email protected]>

2 files changed, 1662 insertions, 0 deletions

diff --git a/src/gallium/auxiliary/tgsi/tgsi_lowering.c b/src/gallium/auxiliary/tgsi/tgsi_lowering.c
new file mode 100644
index 00000000000..795b53729d6
--- /dev/null
+++ b/src/gallium/auxiliary/tgsi/tgsi_lowering.c
@@ -0,0 +1,1573 @@
+/* -*- mode: C; c-file-style: "k&r"; tab-width 4; indent-tabs-mode: t; -*- */
+
+/*
+ * Copyright (C) 2014 Rob Clark <[email protected]>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *
+ * Authors:
+ *    Rob Clark <[email protected]>
+ */
+
+#include "tgsi/tgsi_transform.h"
+#include "tgsi/tgsi_scan.h"
+#include "tgsi/tgsi_dump.h"
+
+#include "util/u_debug.h"
+#include "util/u_math.h"
+
+#include "freedreno_lowering.h"
+
+struct fd_lowering_context {
+	struct tgsi_transform_context base;
+	const struct fd_lowering_config *config;
+	struct tgsi_shader_info *info;
+	unsigned two_side_colors;
+	unsigned two_side_idx[PIPE_MAX_SHADER_INPUTS];
+	unsigned color_base;  /* base register for chosen COLOR/BCOLOR's */
+	int face_idx;
+	unsigned numtmp;
+	struct {
+		struct tgsi_full_src_register src;
+		struct tgsi_full_dst_register dst;
+	} tmp[2];
+#define A 0
+#define B 1
+	struct tgsi_full_src_register imm;
+	int emitted_decls;
+	unsigned saturate;
+};
+
+static inline struct fd_lowering_context *
+fd_lowering_context(struct tgsi_transform_context *tctx)
+{
+	return (struct fd_lowering_context *)tctx;
+}
+
+/*
+ * Utility helpers:
+ */
+
+static void
+reg_dst(struct tgsi_full_dst_register *dst,
+	const struct tgsi_full_dst_register *orig_dst, unsigned wrmask)
+{
+	*dst = *orig_dst;
+	dst->Register.WriteMask &= wrmask;
+	assert(dst->Register.WriteMask);
+}
+
+static inline void
+get_swiz(unsigned *swiz, const struct tgsi_src_register *src)
+{
+	swiz[0] = src->SwizzleX;
+	swiz[1] = src->SwizzleY;
+	swiz[2] = src->SwizzleZ;
+	swiz[3] = src->SwizzleW;
+}
+
+static void
+reg_src(struct tgsi_full_src_register *src,
+	const struct tgsi_full_src_register *orig_src,
+	unsigned sx, unsigned sy, unsigned sz, unsigned sw)
+{
+	unsigned swiz[4];
+	get_swiz(swiz, &orig_src->Register);
+	*src = *orig_src;
+	src->Register.SwizzleX = swiz[sx];
+	src->Register.SwizzleY = swiz[sy];
+	src->Register.SwizzleZ = swiz[sz];
+	src->Register.SwizzleW = swiz[sw];
+}
+
+#define TGSI_SWIZZLE__ TGSI_SWIZZLE_X  /* don't-care value! */
+#define SWIZ(x,y,z,w) TGSI_SWIZZLE_ ## x, TGSI_SWIZZLE_ ## y, \
+		TGSI_SWIZZLE_ ## z, TGSI_SWIZZLE_ ## w
+
+/*
+ * if (dst.x aliases src.x) {
+ *   MOV tmpA.x, src.x
+ *   src = tmpA
+ * }
+ * COS dst.x, src.x
+ * SIN dst.y, src.x
+ * MOV dst.zw, imm{0.0, 1.0}
+ */
+static bool
+aliases(const struct tgsi_full_dst_register *dst, unsigned dst_mask,
+	const struct tgsi_full_src_register *src, unsigned src_mask)
+{
+	if ((dst->Register.File == src->Register.File) &&
+			(dst->Register.Index == src->Register.Index)) {
+		unsigned i, actual_mask = 0;
+		unsigned swiz[4];
+		get_swiz(swiz, &src->Register);
+		for (i = 0; i < 4; i++)
+			if (src_mask & (1 << i))
+				actual_mask |= (1 << swiz[i]);
+		if (actual_mask & dst_mask)
+			return true;
+	}
+	return false;
+}
+
+static void
+create_mov(struct tgsi_transform_context *tctx,
+	const struct tgsi_full_dst_register *dst,
+	const struct tgsi_full_src_register *src,
+	unsigned mask, unsigned saturate)
+{
+	struct tgsi_full_instruction new_inst;
+
+	new_inst = tgsi_default_full_instruction();
+	new_inst.Instruction.Opcode = TGSI_OPCODE_MOV;
+	new_inst.Instruction.Saturate = saturate;
+	new_inst.Instruction.NumDstRegs = 1;
+	reg_dst(&new_inst.Dst[0], dst, mask);
+	new_inst.Instruction.NumSrcRegs = 1;
+	reg_src(&new_inst.Src[0], src, SWIZ(X,Y,Z,W));
+	tctx->emit_instruction(tctx, &new_inst);
+}
+
+/* to help calculate # of tgsi tokens for a lowering.. we assume
+ * the worst case, ie. removed instructions don't have ADDR[] or
+ * anything which increases the # of tokens per src/dst and the
+ * inserted instructions do.
+ *
+ * OINST() - old instruction
+ *    1         : instruction itself
+ *    1         : dst
+ *    1 * nargs : srcN
+ *
+ * NINST() - new instruction
+ *    1         : instruction itself
+ *    2         : dst
+ *    2 * nargs : srcN
+ */
+
+#define OINST(nargs)  (1 + 1 + 1 * (nargs))
+#define NINST(nargs)  (1 + 2 + 2 * (nargs))
+
+/*
+ * Lowering Translators:
+ */
+
+/* DST - Distance Vector
+ *   dst.x = 1.0
+ *   dst.y = src0.y \times src1.y
+ *   dst.z = src0.z
+ *   dst.w = src1.w
+ *
+ * ; note: could be more clever and use just a single temp
+ * ;       if I was clever enough to re-write the swizzles.
+ * ; needs: 2 tmp, imm{1.0}
+ * if (dst.y aliases src0.z) {
+ *   MOV tmpA.yz, src0.yz
+ *   src0 = tmpA
+ * }
+ * if (dst.yz aliases src1.w) {
+ *   MOV tmpB.yw, src1.yw
+ *   src1 = tmpB
+ * }
+ * MUL dst.y, src0.y, src1.y
+ * MOV dst.z, src0.z
+ * MOV dst.w, src1.w
+ * MOV dst.x, imm{1.0}
+ */
+#define DST_GROW (NINST(1) + NINST(1) + NINST(2) + NINST(1) + \
+		NINST(1) + NINST(1) - OINST(2))
+#define DST_TMP  2
+static void
+transform_dst(struct tgsi_transform_context *tctx,
+		struct tgsi_full_instruction *inst)
+{
+	struct fd_lowering_context *ctx = fd_lowering_context(tctx);
+	struct tgsi_full_dst_register *dst  = &inst->Dst[0];
+	struct tgsi_full_src_register *src0 = &inst->Src[0];
+	struct tgsi_full_src_register *src1 = &inst->Src[1];
+	struct tgsi_full_instruction new_inst;
+
+	if (aliases(dst, TGSI_WRITEMASK_Y, src0, TGSI_WRITEMASK_Z)) {
+		create_mov(tctx, &ctx->tmp[A].dst, src0, TGSI_WRITEMASK_YZ, 0);
+		src0 = &ctx->tmp[A].src;
+	}
+
+	if (aliases(dst, TGSI_WRITEMASK_YZ, src1, TGSI_WRITEMASK_W)) {
+		create_mov(tctx, &ctx->tmp[B].dst, src1, TGSI_WRITEMASK_YW, 0);
+		src1 = &ctx->tmp[B].src;
+	}
+
+	if (dst->Register.WriteMask & TGSI_WRITEMASK_Y) {
+		/* MUL dst.y, src0.y, src1.y */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_MUL;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], dst, TGSI_WRITEMASK_Y);
+		new_inst.Instruction.NumSrcRegs = 2;
+		reg_src(&new_inst.Src[0], src0, SWIZ(_,Y,_,_));
+		reg_src(&new_inst.Src[1], src1, SWIZ(_,Y,_,_));
+		tctx->emit_instruction(tctx, &new_inst);
+	}
+
+	if (dst->Register.WriteMask & TGSI_WRITEMASK_Z) {
+		/* MOV dst.z, src0.z */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_MOV;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], dst, TGSI_WRITEMASK_Z);
+		new_inst.Instruction.NumSrcRegs = 1;
+		reg_src(&new_inst.Src[0], src0, SWIZ(_,_,Z,_));
+		tctx->emit_instruction(tctx, &new_inst);
+	}
+
+	if (dst->Register.WriteMask & TGSI_WRITEMASK_W) {
+		/* MOV dst.w, src1.w */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_MOV;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], dst, TGSI_WRITEMASK_W);
+		new_inst.Instruction.NumSrcRegs = 1;
+		reg_src(&new_inst.Src[0], src1, SWIZ(_,_,_,W));
+		tctx->emit_instruction(tctx, &new_inst);
+	}
+
+	if (dst->Register.WriteMask & TGSI_WRITEMASK_X) {
+		/* MOV dst.x, imm{1.0} */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_MOV;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], dst, TGSI_WRITEMASK_X);
+		new_inst.Instruction.NumSrcRegs = 1;
+		reg_src(&new_inst.Src[0], &ctx->imm, SWIZ(Y,_,_,_));
+		tctx->emit_instruction(tctx, &new_inst);
+	}
+}
+
+/* XPD - Cross Product
+ *   dst.x = src0.y \times src1.z - src1.y \times src0.z
+ *   dst.y = src0.z \times src1.x - src1.z \times src0.x
+ *   dst.z = src0.x \times src1.y - src1.x \times src0.y
+ *   dst.w = 1.0
+ *
+ * ; needs: 2 tmp, imm{1.0}
+ * MUL tmpA.xyz, src0.yzx, src1.zxy
+ * MUL tmpB.xyz, src1.yzx, src0.zxy
+ * SUB dst.xyz, tmpA.xyz, tmpB.xyz
+ * MOV dst.w, imm{1.0}
+ */
+#define XPD_GROW (NINST(2) + NINST(2) + NINST(2) + NINST(1) - OINST(2))
+#define XPD_TMP  2
+static void
+transform_xpd(struct tgsi_transform_context *tctx,
+		struct tgsi_full_instruction *inst)
+{
+	struct fd_lowering_context *ctx = fd_lowering_context(tctx);
+	struct tgsi_full_dst_register *dst  = &inst->Dst[0];
+	struct tgsi_full_src_register *src0 = &inst->Src[0];
+	struct tgsi_full_src_register *src1 = &inst->Src[1];
+	struct tgsi_full_instruction new_inst;
+
+	if (dst->Register.WriteMask & TGSI_WRITEMASK_XYZ) {
+		/* MUL tmpA.xyz, src0.yzx, src1.zxy */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_MUL;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], &ctx->tmp[A].dst, TGSI_WRITEMASK_XYZ);
+		new_inst.Instruction.NumSrcRegs = 2;
+		reg_src(&new_inst.Src[0], src0, SWIZ(Y,Z,X,_));
+		reg_src(&new_inst.Src[1], src1, SWIZ(Z,X,Y,_));
+		tctx->emit_instruction(tctx, &new_inst);
+
+		/* MUL tmpB.xyz, src1.yzx, src0.zxy */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_MUL;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], &ctx->tmp[B].dst, TGSI_WRITEMASK_XYZ);
+		new_inst.Instruction.NumSrcRegs = 2;
+		reg_src(&new_inst.Src[0], src1, SWIZ(Y,Z,X,_));
+		reg_src(&new_inst.Src[1], src0, SWIZ(Z,X,Y,_));
+		tctx->emit_instruction(tctx, &new_inst);
+
+		/* SUB dst.xyz, tmpA.xyz, tmpB.xyz */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_SUB;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], dst, TGSI_WRITEMASK_XYZ);
+		new_inst.Instruction.NumSrcRegs = 2;
+		reg_src(&new_inst.Src[0], &ctx->tmp[A].src, SWIZ(X,Y,Z,_));
+		reg_src(&new_inst.Src[1], &ctx->tmp[B].src, SWIZ(X,Y,Z,_));
+		tctx->emit_instruction(tctx, &new_inst);
+	}
+
+	if (dst->Register.WriteMask & TGSI_WRITEMASK_W) {
+		/* MOV dst.w, imm{1.0} */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_MOV;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], dst, TGSI_WRITEMASK_W);
+		new_inst.Instruction.NumSrcRegs = 1;
+		reg_src(&new_inst.Src[0], &ctx->imm, SWIZ(_,_,_,Y));
+		tctx->emit_instruction(tctx, &new_inst);
+	}
+}
+
+/* SCS - Sine Cosine
+ *   dst.x = \cos{src.x}
+ *   dst.y = \sin{src.x}
+ *   dst.z = 0.0
+ *   dst.w = 1.0
+ *
+ * ; needs: 1 tmp, imm{0.0, 1.0}
+ * if (dst.x aliases src.x) {
+ *   MOV tmpA.x, src.x
+ *   src = tmpA
+ * }
+ * COS dst.x, src.x
+ * SIN dst.y, src.x
+ * MOV dst.zw, imm{0.0, 1.0}
+ */
+#define SCS_GROW (NINST(1) + NINST(1) + NINST(1) + NINST(1) - OINST(1))
+#define SCS_TMP  1
+static void
+transform_scs(struct tgsi_transform_context *tctx,
+		struct tgsi_full_instruction *inst)
+{
+	struct fd_lowering_context *ctx = fd_lowering_context(tctx);
+	struct tgsi_full_dst_register *dst = &inst->Dst[0];
+	struct tgsi_full_src_register *src = &inst->Src[0];
+	struct tgsi_full_instruction new_inst;
+
+	if (aliases(dst, TGSI_WRITEMASK_X, src, TGSI_WRITEMASK_X)) {
+		create_mov(tctx, &ctx->tmp[A].dst, src, TGSI_WRITEMASK_X, 0);
+		src = &ctx->tmp[A].src;
+	}
+
+	if (dst->Register.WriteMask & TGSI_WRITEMASK_X) {
+		/* COS dst.x, src.x */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_COS;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], dst, TGSI_WRITEMASK_X);
+		new_inst.Instruction.NumSrcRegs = 1;
+		reg_src(&new_inst.Src[0], src, SWIZ(X,_,_,_));
+		tctx->emit_instruction(tctx, &new_inst);
+	}
+
+	if (dst->Register.WriteMask & TGSI_WRITEMASK_Y) {
+		/* SIN dst.y, src.x */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_SIN;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], dst, TGSI_WRITEMASK_Y);
+		new_inst.Instruction.NumSrcRegs = 1;
+		reg_src(&new_inst.Src[0], src, SWIZ(X,_,_,_));
+		tctx->emit_instruction(tctx, &new_inst);
+	}
+
+	if (dst->Register.WriteMask & TGSI_WRITEMASK_ZW) {
+		/* MOV dst.zw, imm{0.0, 1.0} */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_MOV;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], dst, TGSI_WRITEMASK_ZW);
+		new_inst.Instruction.NumSrcRegs = 1;
+		reg_src(&new_inst.Src[0], &ctx->imm, SWIZ(_,_,X,Y));
+		tctx->emit_instruction(tctx, &new_inst);
+	}
+}
+
+/* LRP - Linear Interpolate
+ *  dst.x = src0.x \times src1.x + (1.0 - src0.x) \times src2.x
+ *  dst.y = src0.y \times src1.y + (1.0 - src0.y) \times src2.y
+ *  dst.z = src0.z \times src1.z + (1.0 - src0.z) \times src2.z
+ *  dst.w = src0.w \times src1.w + (1.0 - src0.w) \times src2.w
+ *
+ * ; needs: 2 tmp, imm{1.0}
+ * MUL tmpA, src0, src1
+ * SUB tmpB, imm{1.0}, src0
+ * MUL tmpB, tmpB, src2
+ * ADD dst, tmpA, tmpB
+ */
+#define LRP_GROW (NINST(2) + NINST(2) + NINST(2) + NINST(2) - OINST(3))
+#define LRP_TMP  2
+static void
+transform_lrp(struct tgsi_transform_context *tctx,
+		struct tgsi_full_instruction *inst)
+{
+	struct fd_lowering_context *ctx = fd_lowering_context(tctx);
+	struct tgsi_full_dst_register *dst  = &inst->Dst[0];
+	struct tgsi_full_src_register *src0 = &inst->Src[0];
+	struct tgsi_full_src_register *src1 = &inst->Src[1];
+	struct tgsi_full_src_register *src2 = &inst->Src[2];
+	struct tgsi_full_instruction new_inst;
+
+	if (dst->Register.WriteMask & TGSI_WRITEMASK_XYZW) {
+		/* MUL tmpA, src0, src1 */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_MUL;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], &ctx->tmp[A].dst, TGSI_WRITEMASK_XYZW);
+		new_inst.Instruction.NumSrcRegs = 2;
+		reg_src(&new_inst.Src[0], src0, SWIZ(X,Y,Z,W));
+		reg_src(&new_inst.Src[1], src1, SWIZ(X,Y,Z,W));
+		tctx->emit_instruction(tctx, &new_inst);
+
+		/* SUB tmpB, imm{1.0}, src0 */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_SUB;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], &ctx->tmp[B].dst, TGSI_WRITEMASK_XYZW);
+		new_inst.Instruction.NumSrcRegs = 2;
+		reg_src(&new_inst.Src[0], &ctx->imm, SWIZ(Y,Y,Y,Y));
+		reg_src(&new_inst.Src[1], src0, SWIZ(X,Y,Z,W));
+		tctx->emit_instruction(tctx, &new_inst);
+
+		/* MUL tmpB, tmpB, src2 */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_MUL;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], &ctx->tmp[B].dst, TGSI_WRITEMASK_XYZW);
+		new_inst.Instruction.NumSrcRegs = 2;
+		reg_src(&new_inst.Src[0], &ctx->tmp[B].src, SWIZ(X,Y,Z,W));
+		reg_src(&new_inst.Src[1], src2, SWIZ(X,Y,Z,W));
+		tctx->emit_instruction(tctx, &new_inst);
+
+		/* ADD dst, tmpA, tmpB */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_ADD;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], dst, TGSI_WRITEMASK_XYZW);
+		new_inst.Instruction.NumSrcRegs = 2;
+		reg_src(&new_inst.Src[0], &ctx->tmp[A].src, SWIZ(X,Y,Z,W));
+		reg_src(&new_inst.Src[1], &ctx->tmp[B].src, SWIZ(X,Y,Z,W));
+		tctx->emit_instruction(tctx, &new_inst);
+	}
+}
+
+/* FRC - Fraction
+ *  dst.x = src.x - \lfloor src.x\rfloor
+ *  dst.y = src.y - \lfloor src.y\rfloor
+ *  dst.z = src.z - \lfloor src.z\rfloor
+ *  dst.w = src.w - \lfloor src.w\rfloor
+ *
+ * ; needs: 1 tmp
+ * FLR tmpA, src
+ * SUB dst, src, tmpA
+ */
+#define FRC_GROW (NINST(1) + NINST(2) - OINST(1))
+#define FRC_TMP  1
+static void
+transform_frc(struct tgsi_transform_context *tctx,
+		struct tgsi_full_instruction *inst)
+{
+	struct fd_lowering_context *ctx = fd_lowering_context(tctx);
+	struct tgsi_full_dst_register *dst = &inst->Dst[0];
+	struct tgsi_full_src_register *src = &inst->Src[0];
+	struct tgsi_full_instruction new_inst;
+
+	if (dst->Register.WriteMask & TGSI_WRITEMASK_XYZW) {
+		/* FLR tmpA, src */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_FLR;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], &ctx->tmp[A].dst, TGSI_WRITEMASK_XYZW);
+		new_inst.Instruction.NumSrcRegs = 1;
+		reg_src(&new_inst.Src[0], src, SWIZ(X,Y,Z,W));
+		tctx->emit_instruction(tctx, &new_inst);
+
+		/* SUB dst, src, tmpA */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_SUB;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], dst, TGSI_WRITEMASK_XYZW);
+		new_inst.Instruction.NumSrcRegs = 2;
+		reg_src(&new_inst.Src[0], src, SWIZ(X,Y,Z,W));
+		reg_src(&new_inst.Src[1], &ctx->tmp[A].src, SWIZ(X,Y,Z,W));
+		tctx->emit_instruction(tctx, &new_inst);
+	}
+}
+
+/* POW - Power
+ *  dst.x = src0.x^{src1.x}
+ *  dst.y = src0.x^{src1.x}
+ *  dst.z = src0.x^{src1.x}
+ *  dst.w = src0.x^{src1.x}
+ *
+ * ; needs: 1 tmp
+ * LG2 tmpA.x, src0.x
+ * MUL tmpA.x, src1.x, tmpA.x
+ * EX2 dst, tmpA.x
+ */
+#define POW_GROW (NINST(1) + NINST(2) + NINST(1) - OINST(2))
+#define POW_TMP  1
+static void
+transform_pow(struct tgsi_transform_context *tctx,
+		struct tgsi_full_instruction *inst)
+{
+	struct fd_lowering_context *ctx = fd_lowering_context(tctx);
+	struct tgsi_full_dst_register *dst  = &inst->Dst[0];
+	struct tgsi_full_src_register *src0 = &inst->Src[0];
+	struct tgsi_full_src_register *src1 = &inst->Src[1];
+	struct tgsi_full_instruction new_inst;
+
+	if (dst->Register.WriteMask & TGSI_WRITEMASK_XYZW) {
+		/* LG2 tmpA.x, src0.x */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_LG2;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], &ctx->tmp[A].dst, TGSI_WRITEMASK_X);
+		new_inst.Instruction.NumSrcRegs = 1;
+		reg_src(&new_inst.Src[0], src0, SWIZ(X,_,_,_));
+		tctx->emit_instruction(tctx, &new_inst);
+
+		/* MUL tmpA.x, src1.x, tmpA.x */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_MUL;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], &ctx->tmp[A].dst, TGSI_WRITEMASK_X);
+		new_inst.Instruction.NumSrcRegs = 2;
+		reg_src(&new_inst.Src[0], src1, SWIZ(X,_,_,_));
+		reg_src(&new_inst.Src[1], &ctx->tmp[A].src, SWIZ(X,_,_,_));
+		tctx->emit_instruction(tctx, &new_inst);
+
+		/* EX2 dst, tmpA.x */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_EX2;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], dst, TGSI_WRITEMASK_XYZW);
+		new_inst.Instruction.NumSrcRegs = 1;
+		reg_src(&new_inst.Src[0], &ctx->tmp[A].src, SWIZ(X,_,_,_));
+		tctx->emit_instruction(tctx, &new_inst);
+	}
+}
+
+/* LIT - Light Coefficients
+ *  dst.x = 1.0
+ *  dst.y = max(src.x, 0.0)
+ *  dst.z = (src.x > 0.0) ? max(src.y, 0.0)^{clamp(src.w, -128.0, 128.0))} : 0
+ *  dst.w = 1.0
+ *
+ * ; needs: 1 tmp, imm{0.0}, imm{1.0}, imm{128.0}
+ * MAX tmpA.xy, src.xy, imm{0.0}
+ * CLAMP tmpA.z, src.w, -imm{128.0}, imm{128.0}
+ * LG2 tmpA.y, tmpA.y
+ * MUL tmpA.y, tmpA.z, tmpA.y
+ * EX2 tmpA.y, tmpA.y
+ * CMP tmpA.y, -src.x, tmpA.y, imm{0.0}
+ * MOV dst.yz, tmpA.xy
+ * MOV dst.xw, imm{1.0}
+ */
+#define LIT_GROW (NINST(1) + NINST(3) + NINST(1) + NINST(2) + \
+		NINST(1) + NINST(3) + NINST(1) + NINST(1) - OINST(1))
+#define LIT_TMP  1
+static void
+transform_lit(struct tgsi_transform_context *tctx,
+		struct tgsi_full_instruction *inst)
+{
+	struct fd_lowering_context *ctx = fd_lowering_context(tctx);
+	struct tgsi_full_dst_register *dst = &inst->Dst[0];
+	struct tgsi_full_src_register *src = &inst->Src[0];
+	struct tgsi_full_instruction new_inst;
+
+	if (dst->Register.WriteMask & TGSI_WRITEMASK_YZ) {
+		/* MAX tmpA.xy, src.xy, imm{0.0} */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_MAX;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], &ctx->tmp[A].dst, TGSI_WRITEMASK_XY);
+		new_inst.Instruction.NumSrcRegs = 2;
+		reg_src(&new_inst.Src[0], src, SWIZ(X,Y,_,_));
+		reg_src(&new_inst.Src[1], &ctx->imm, SWIZ(X,X,_,_));
+		tctx->emit_instruction(tctx, &new_inst);
+
+		/* CLAMP tmpA.z, src.w, -imm{128.0}, imm{128.0} */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_CLAMP;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], &ctx->tmp[A].dst, TGSI_WRITEMASK_Z);
+		new_inst.Instruction.NumSrcRegs = 3;
+		reg_src(&new_inst.Src[0], src, SWIZ(_,_,W,_));
+		reg_src(&new_inst.Src[1], &ctx->imm, SWIZ(_,_,Z,_));
+		new_inst.Src[1].Register.Negate = true;
+		reg_src(&new_inst.Src[2], &ctx->imm, SWIZ(_,_,Z,_));
+		tctx->emit_instruction(tctx, &new_inst);
+
+		/* LG2 tmpA.y, tmpA.y */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_LG2;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], &ctx->tmp[A].dst, TGSI_WRITEMASK_Y);
+		new_inst.Instruction.NumSrcRegs = 1;
+		reg_src(&new_inst.Src[0], &ctx->tmp[A].src, SWIZ(Y,_,_,_));
+		tctx->emit_instruction(tctx, &new_inst);
+
+		/* MUL tmpA.y, tmpA.z, tmpA.y */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_MUL;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], &ctx->tmp[A].dst, TGSI_WRITEMASK_Y);
+		new_inst.Instruction.NumSrcRegs = 2;
+		reg_src(&new_inst.Src[0], &ctx->tmp[A].src, SWIZ(_,Z,_,_));
+		reg_src(&new_inst.Src[1], &ctx->tmp[A].src, SWIZ(_,Y,_,_));
+		tctx->emit_instruction(tctx, &new_inst);
+
+		/* EX2 tmpA.y, tmpA.y */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_EX2;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], &ctx->tmp[A].dst, TGSI_WRITEMASK_Y);
+		new_inst.Instruction.NumSrcRegs = 1;
+		reg_src(&new_inst.Src[0], &ctx->tmp[A].src, SWIZ(Y,_,_,_));
+		tctx->emit_instruction(tctx, &new_inst);
+
+		/* CMP tmpA.y, -src.x, tmpA.y, imm{0.0} */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_CMP;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], &ctx->tmp[A].dst, TGSI_WRITEMASK_Y);
+		new_inst.Instruction.NumSrcRegs = 3;
+		reg_src(&new_inst.Src[0], src, SWIZ(_,X,_,_));
+		new_inst.Src[0].Register.Negate = true;
+		reg_src(&new_inst.Src[1], &ctx->tmp[A].src, SWIZ(_,Y,_,_));
+		reg_src(&new_inst.Src[2], &ctx->imm, SWIZ(_,X,_,_));
+		tctx->emit_instruction(tctx, &new_inst);
+
+		/* MOV dst.yz, tmpA.xy */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_MOV;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], dst, TGSI_WRITEMASK_YZ);
+		new_inst.Instruction.NumSrcRegs = 1;
+		reg_src(&new_inst.Src[0], &ctx->tmp[A].src, SWIZ(_,X,Y,_));
+		tctx->emit_instruction(tctx, &new_inst);
+	}
+
+	if (dst->Register.WriteMask & TGSI_WRITEMASK_XW) {
+		/* MOV dst.xw, imm{1.0} */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_MOV;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], dst, TGSI_WRITEMASK_XW);
+		new_inst.Instruction.NumSrcRegs = 1;
+		reg_src(&new_inst.Src[0], &ctx->imm, SWIZ(Y,_,_,Y));
+		tctx->emit_instruction(tctx, &new_inst);
+	}
+}
+
+/* EXP - Approximate Exponential Base 2
+ *  dst.x = 2^{\lfloor src.x\rfloor}
+ *  dst.y = src.x - \lfloor src.x\rfloor
+ *  dst.z = 2^{src.x}
+ *  dst.w = 1.0
+ *
+ * ; needs: 1 tmp, imm{1.0}
+ * FLR tmpA.x, src.x
+ * EX2 tmpA.y, src.x
+ * SUB dst.y, src.x, tmpA.x
+ * EX2 dst.x, tmpA.x
+ * MOV dst.z, tmpA.y
+ * MOV dst.w, imm{1.0}
+ */
+#define EXP_GROW (NINST(1) + NINST(1) + NINST(2) + NINST(1) + \
+		NINST(1)+ NINST(1) - OINST(1))
+#define EXP_TMP  1
+static void
+transform_exp(struct tgsi_transform_context *tctx,
+		struct tgsi_full_instruction *inst)
+{
+	struct fd_lowering_context *ctx = fd_lowering_context(tctx);
+	struct tgsi_full_dst_register *dst = &inst->Dst[0];
+	struct tgsi_full_src_register *src = &inst->Src[0];
+	struct tgsi_full_instruction new_inst;
+
+	if (dst->Register.WriteMask & TGSI_WRITEMASK_XY) {
+		/* FLR tmpA.x, src.x */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_FLR;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], &ctx->tmp[A].dst, TGSI_WRITEMASK_X);
+		new_inst.Instruction.NumSrcRegs = 1;
+		reg_src(&new_inst.Src[0], src, SWIZ(X,_,_,_));
+		tctx->emit_instruction(tctx, &new_inst);
+	}
+
+	if (dst->Register.WriteMask & TGSI_WRITEMASK_Z) {
+		/* EX2 tmpA.y, src.x */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_EX2;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], &ctx->tmp[A].dst, TGSI_WRITEMASK_Y);
+		new_inst.Instruction.NumSrcRegs = 1;
+		reg_src(&new_inst.Src[0], src, SWIZ(X,_,_,_));
+		tctx->emit_instruction(tctx, &new_inst);
+	}
+
+	if (dst->Register.WriteMask & TGSI_WRITEMASK_Y) {
+		/* SUB dst.y, src.x, tmpA.x */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_SUB;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], dst, TGSI_WRITEMASK_Y);
+		new_inst.Instruction.NumSrcRegs = 2;
+		reg_src(&new_inst.Src[0], src, SWIZ(_,X,_,_));
+		reg_src(&new_inst.Src[1], &ctx->tmp[A].src, SWIZ(_,X,_,_));
+		tctx->emit_instruction(tctx, &new_inst);
+	}
+
+	if (dst->Register.WriteMask & TGSI_WRITEMASK_X) {
+		/* EX2 dst.x, tmpA.x */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_EX2;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], dst, TGSI_WRITEMASK_X);
+		new_inst.Instruction.NumSrcRegs = 1;
+		reg_src(&new_inst.Src[0], &ctx->tmp[A].src, SWIZ(X,_,_,_));
+		tctx->emit_instruction(tctx, &new_inst);
+	}
+
+	if (dst->Register.WriteMask & TGSI_WRITEMASK_Z) {
+		/* MOV dst.z, tmpA.y */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_MOV;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], dst, TGSI_WRITEMASK_Z);
+		new_inst.Instruction.NumSrcRegs = 1;
+		reg_src(&new_inst.Src[0], &ctx->tmp[A].src, SWIZ(_,_,Y,_));
+		tctx->emit_instruction(tctx, &new_inst);
+	}
+
+	if (dst->Register.WriteMask & TGSI_WRITEMASK_W) {
+		/* MOV dst.w, imm{1.0} */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_MOV;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], dst, TGSI_WRITEMASK_W);
+		new_inst.Instruction.NumSrcRegs = 1;
+		reg_src(&new_inst.Src[0], &ctx->imm, SWIZ(_,_,_,Y));
+		tctx->emit_instruction(tctx, &new_inst);
+	}
+}
+
+/* LOG - Approximate Logarithm Base 2
+ *  dst.x = \lfloor\log_2{|src.x|}\rfloor
+ *  dst.y = \frac{|src.x|}{2^{\lfloor\log_2{|src.x|}\rfloor}}
+ *  dst.z = \log_2{|src.x|}
+ *  dst.w = 1.0
+ *
+ * ; needs: 1 tmp, imm{1.0}
+ * LG2 tmpA.x, |src.x|
+ * FLR tmpA.y, tmpA.x
+ * EX2 tmpA.z, tmpA.y
+ * RCP tmpA.z, tmpA.z
+ * MUL dst.y, |src.x|, tmpA.z
+ * MOV dst.xz, tmpA.yx
+ * MOV dst.w, imm{1.0}
+ */
+#define LOG_GROW (NINST(1) + NINST(1) + NINST(1) + NINST(1) + \
+		NINST(2) + NINST(1) + NINST(1) - OINST(1))
+#define LOG_TMP  1
+static void
+transform_log(struct tgsi_transform_context *tctx,
+		struct tgsi_full_instruction *inst)
+{
+	struct fd_lowering_context *ctx = fd_lowering_context(tctx);
+	struct tgsi_full_dst_register *dst = &inst->Dst[0];
+	struct tgsi_full_src_register *src = &inst->Src[0];
+	struct tgsi_full_instruction new_inst;
+
+	if (dst->Register.WriteMask & TGSI_WRITEMASK_XYZ) {
+		/* LG2 tmpA.x, |src.x| */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_LG2;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], &ctx->tmp[A].dst, TGSI_WRITEMASK_X);
+		new_inst.Instruction.NumSrcRegs = 1;
+		reg_src(&new_inst.Src[0], src, SWIZ(X,_,_,_));
+		new_inst.Src[0].Register.Absolute = true;
+		tctx->emit_instruction(tctx, &new_inst);
+	}
+
+	if (dst->Register.WriteMask & TGSI_WRITEMASK_XY) {
+		/* FLR tmpA.y, tmpA.x */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_FLR;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], &ctx->tmp[A].dst, TGSI_WRITEMASK_Y);
+		new_inst.Instruction.NumSrcRegs = 1;
+		reg_src(&new_inst.Src[0], &ctx->tmp[A].src, SWIZ(_,X,_,_));
+		tctx->emit_instruction(tctx, &new_inst);
+	}
+
+	if (dst->Register.WriteMask & TGSI_WRITEMASK_Y) {
+		/* EX2 tmpA.z, tmpA.y */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_EX2;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], &ctx->tmp[A].dst, TGSI_WRITEMASK_Z);
+		new_inst.Instruction.NumSrcRegs = 1;
+		reg_src(&new_inst.Src[0], &ctx->tmp[A].src, SWIZ(Y,_,_,_));
+		tctx->emit_instruction(tctx, &new_inst);
+
+		/* RCP tmpA.z, tmpA.z */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_RCP;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], &ctx->tmp[A].dst, TGSI_WRITEMASK_Z);
+		new_inst.Instruction.NumSrcRegs = 1;
+		reg_src(&new_inst.Src[0], &ctx->tmp[A].src, SWIZ(Z,_,_,_));
+		tctx->emit_instruction(tctx, &new_inst);
+
+		/* MUL dst.y, |src.x|, tmpA.z */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_MUL;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], dst, TGSI_WRITEMASK_Y);
+		new_inst.Instruction.NumSrcRegs = 2;
+		reg_src(&new_inst.Src[0], src, SWIZ(_,X,_,_));
+		new_inst.Src[0].Register.Absolute = true;
+		reg_src(&new_inst.Src[1], &ctx->tmp[A].src, SWIZ(_,Z,_,_));
+		tctx->emit_instruction(tctx, &new_inst);
+	}
+
+	if (dst->Register.WriteMask & TGSI_WRITEMASK_XZ) {
+		/* MOV dst.xz, tmpA.yx */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_MOV;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], dst, TGSI_WRITEMASK_XZ);
+		new_inst.Instruction.NumSrcRegs = 1;
+		reg_src(&new_inst.Src[0], &ctx->tmp[A].src, SWIZ(Y,_,X,_));
+		tctx->emit_instruction(tctx, &new_inst);
+	}
+
+	if (dst->Register.WriteMask & TGSI_WRITEMASK_W) {
+		/* MOV dst.w, imm{1.0} */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_MOV;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], dst, TGSI_WRITEMASK_W);
+		new_inst.Instruction.NumSrcRegs = 1;
+		reg_src(&new_inst.Src[0], &ctx->imm, SWIZ(_,_,_,Y));
+		tctx->emit_instruction(tctx, &new_inst);
+	}
+}
+
+/* DP4 - 4-component Dot Product
+ *   dst = src0.x \times src1.x + src0.y \times src1.y + src0.z \times src1.z + src0.w \times src1.w
+ *
+ * DP3 - 3-component Dot Product
+ *   dst = src0.x \times src1.x + src0.y \times src1.y + src0.z \times src1.z
+ *
+ * DPH - Homogeneous Dot Product
+ *   dst = src0.x \times src1.x + src0.y \times src1.y + src0.z \times src1.z + src1.w
+ *
+ * DP2 - 2-component Dot Product
+ *   dst = src0.x \times src1.x + src0.y \times src1.y
+ *
+ * DP2A - 2-component Dot Product And Add
+ *   dst = src0.x \times src1.x + src0.y \times src1.y + src2.x
+ *
+ * NOTE: these are translated into sequence of MUL/MAD(/ADD) scalar
+ * operations, which is what you'd prefer for a ISA that is natively
+ * scalar.  Probably a native vector ISA would at least already have
+ * DP4/DP3 instructions, but perhaps there is room for an alternative
+ * translation for DPH/DP2/DP2A using vector instructions.
+ *
+ * ; needs: 1 tmp
+ * MUL tmpA.x, src0.x, src1.x
+ * MAD tmpA.x, src0.y, src1.y, tmpA.x
+ * if (DPH || DP3 || DP4) {
+ *   MAD tmpA.x, src0.z, src1.z, tmpA.x
+ *   if (DPH) {
+ *     ADD tmpA.x, src1.w, tmpA.x
+ *   } else if (DP4) {
+ *     MAD tmpA.x, src0.w, src1.w, tmpA.x
+ *   }
+ * } else if (DP2A) {
+ *   ADD tmpA.x, src2.x, tmpA.x
+ * }
+ * ; fixup last instruction to replicate into dst
+ */
+#define DP4_GROW  (NINST(2) + NINST(3) + NINST(3) + NINST(3) - OINST(2))
+#define DP3_GROW  (NINST(2) + NINST(3) + NINST(3) - OINST(2))
+#define DPH_GROW  (NINST(2) + NINST(3) + NINST(3) + NINST(2) - OINST(2))
+#define DP2_GROW  (NINST(2) + NINST(3) - OINST(2))
+#define DP2A_GROW (NINST(2) + NINST(3) + NINST(2) - OINST(3))
+#define DOTP_TMP  1
+static void
+transform_dotp(struct tgsi_transform_context *tctx,
+		struct tgsi_full_instruction *inst)
+{
+	struct fd_lowering_context *ctx = fd_lowering_context(tctx);
+	struct tgsi_full_dst_register *dst  = &inst->Dst[0];
+	struct tgsi_full_src_register *src0 = &inst->Src[0];
+	struct tgsi_full_src_register *src1 = &inst->Src[1];
+	struct tgsi_full_src_register *src2 = &inst->Src[2]; /* only DP2A */
+	struct tgsi_full_instruction new_inst;
+	unsigned opcode = inst->Instruction.Opcode;
+
+	/* NOTE: any potential last instruction must replicate src on all
+	 * components (since it could be re-written to write to final dst)
+	 */
+
+	if (dst->Register.WriteMask & TGSI_WRITEMASK_XYZW) {
+		/* MUL tmpA.x, src0.x, src1.x */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_MUL;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], &ctx->tmp[A].dst, TGSI_WRITEMASK_X);
+		new_inst.Instruction.NumSrcRegs = 2;
+		reg_src(&new_inst.Src[0], src0, SWIZ(X,_,_,_));
+		reg_src(&new_inst.Src[1], src1, SWIZ(X,_,_,_));
+		tctx->emit_instruction(tctx, &new_inst);
+
+		/* MAD tmpA.x, src0.y, src1.y, tmpA.x */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_MAD;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], &ctx->tmp[A].dst, TGSI_WRITEMASK_X);
+		new_inst.Instruction.NumSrcRegs = 3;
+		reg_src(&new_inst.Src[0], src0, SWIZ(Y,Y,Y,Y));
+		reg_src(&new_inst.Src[1], src1, SWIZ(Y,Y,Y,Y));
+		reg_src(&new_inst.Src[2], &ctx->tmp[A].src, SWIZ(X,X,X,X));
+
+		if ((opcode == TGSI_OPCODE_DPH) ||
+				(opcode == TGSI_OPCODE_DP3) ||
+				(opcode == TGSI_OPCODE_DP4)) {
+			tctx->emit_instruction(tctx, &new_inst);
+
+			/* MAD tmpA.x, src0.z, src1.z, tmpA.x */
+			new_inst = tgsi_default_full_instruction();
+			new_inst.Instruction.Opcode = TGSI_OPCODE_MAD;
+			new_inst.Instruction.NumDstRegs = 1;
+			reg_dst(&new_inst.Dst[0], &ctx->tmp[A].dst, TGSI_WRITEMASK_X);
+			new_inst.Instruction.NumSrcRegs = 3;
+			reg_src(&new_inst.Src[0], src0, SWIZ(Z,Z,Z,Z));
+			reg_src(&new_inst.Src[1], src1, SWIZ(Z,Z,Z,Z));
+			reg_src(&new_inst.Src[2], &ctx->tmp[A].src, SWIZ(X,X,X,X));
+
+			if (opcode == TGSI_OPCODE_DPH) {
+				tctx->emit_instruction(tctx, &new_inst);
+
+				/* ADD tmpA.x, src1.w, tmpA.x */
+				new_inst = tgsi_default_full_instruction();
+				new_inst.Instruction.Opcode = TGSI_OPCODE_ADD;
+				new_inst.Instruction.NumDstRegs = 1;
+				reg_dst(&new_inst.Dst[0], &ctx->tmp[A].dst, TGSI_WRITEMASK_X);
+				new_inst.Instruction.NumSrcRegs = 2;
+				reg_src(&new_inst.Src[0], src1, SWIZ(W,W,W,W));
+				reg_src(&new_inst.Src[1], &ctx->tmp[A].src, SWIZ(X,X,X,X));
+			} else if (opcode == TGSI_OPCODE_DP4) {
+				tctx->emit_instruction(tctx, &new_inst);
+
+				/* MAD tmpA.x, src0.w, src1.w, tmpA.x */
+				new_inst = tgsi_default_full_instruction();
+				new_inst.Instruction.Opcode = TGSI_OPCODE_MAD;
+				new_inst.Instruction.NumDstRegs = 1;
+				reg_dst(&new_inst.Dst[0], &ctx->tmp[A].dst, TGSI_WRITEMASK_X);
+				new_inst.Instruction.NumSrcRegs = 3;
+				reg_src(&new_inst.Src[0], src0, SWIZ(W,W,W,W));
+				reg_src(&new_inst.Src[1], src1, SWIZ(W,W,W,W));
+				reg_src(&new_inst.Src[2], &ctx->tmp[A].src, SWIZ(X,X,X,X));
+			}
+		} else if (opcode == TGSI_OPCODE_DP2A) {
+			tctx->emit_instruction(tctx, &new_inst);
+
+			/* ADD tmpA.x, src2.x, tmpA.x */
+			new_inst = tgsi_default_full_instruction();
+			new_inst.Instruction.Opcode = TGSI_OPCODE_ADD;
+			new_inst.Instruction.NumDstRegs = 1;
+			reg_dst(&new_inst.Dst[0], &ctx->tmp[A].dst, TGSI_WRITEMASK_X);
+			new_inst.Instruction.NumSrcRegs = 2;
+			reg_src(&new_inst.Src[0], src2, SWIZ(X,X,X,X));
+			reg_src(&new_inst.Src[1], &ctx->tmp[A].src, SWIZ(X,X,X,X));
+		}
+
+		/* fixup last instruction to write to dst: */
+		reg_dst(&new_inst.Dst[0], dst, TGSI_WRITEMASK_XYZW);
+
+		tctx->emit_instruction(tctx, &new_inst);
+	}
+}
+
+/* Inserts a MOV_SAT for the needed components of tex coord.  Note that
+ * in the case of TXP, the clamping must happen *after* projection, so
+ * we need to lower TXP to TEX.
+ *
+ *   MOV tmpA, src0
+ *   if (opc == TXP) {
+ *     ; do perspective division manually before clamping:
+ *     RCP tmpB, tmpA.w
+ *     MUL tmpB.<pmask>, tmpA, tmpB.xxxx
+ *     opc = TEX;
+ *   }
+ *   MOV_SAT tmpA.<mask>, tmpA  ; <mask> is the clamped s/t/r coords
+ *   <opc> dst, tmpA, ...
+ */
+#define SAMP_GROW (NINST(1) + NINST(1) + NINST(2) + NINST(1))
+#define SAMP_TMP  2
+static int
+transform_samp(struct tgsi_transform_context *tctx,
+		struct tgsi_full_instruction *inst)
+{
+	struct fd_lowering_context *ctx = fd_lowering_context(tctx);
+	struct tgsi_full_src_register *coord = &inst->Src[0];
+	struct tgsi_full_src_register *samp;
+	struct tgsi_full_instruction new_inst;
+	/* mask is clamped coords, pmask is all coords (for projection): */
+	unsigned mask = 0, pmask = 0, smask;
+	unsigned opcode = inst->Instruction.Opcode;
+
+	if (opcode == TGSI_OPCODE_TXB2) {
+		samp = &inst->Src[2];
+	} else {
+		samp = &inst->Src[1];
+	}
+
+	/* convert sampler # to bitmask to test: */
+	smask = 1 << samp->Register.Index;
+
+	/* check if we actually need to lower this one: */
+	if (!(ctx->saturate & smask))
+		return -1;
+
+	/* figure out which coordinates need saturating:
+	 *   - RECT textures should not get saturated
+	 *   - array index coords should not get saturated
+	 */
+	switch (inst->Texture.Texture) {
+	case TGSI_TEXTURE_3D:
+	case TGSI_TEXTURE_CUBE:
+	case TGSI_TEXTURE_CUBE_ARRAY:
+	case TGSI_TEXTURE_SHADOWCUBE:
+	case TGSI_TEXTURE_SHADOWCUBE_ARRAY:
+		if (ctx->config->saturate_r & smask)
+			mask |= TGSI_WRITEMASK_Z;
+		pmask |= TGSI_WRITEMASK_Z;
+		/* fallthrough */
+
+	case TGSI_TEXTURE_2D:
+	case TGSI_TEXTURE_2D_ARRAY:
+	case TGSI_TEXTURE_SHADOW2D:
+	case TGSI_TEXTURE_SHADOW2D_ARRAY:
+	case TGSI_TEXTURE_2D_MSAA:
+	case TGSI_TEXTURE_2D_ARRAY_MSAA:
+		if (ctx->config->saturate_t & smask)
+			mask |= TGSI_WRITEMASK_Y;
+		pmask |= TGSI_WRITEMASK_Y;
+		/* fallthrough */
+
+	case TGSI_TEXTURE_1D:
+	case TGSI_TEXTURE_1D_ARRAY:
+	case TGSI_TEXTURE_SHADOW1D:
+	case TGSI_TEXTURE_SHADOW1D_ARRAY:
+		if (ctx->config->saturate_s & smask)
+			mask |= TGSI_WRITEMASK_X;
+		pmask |= TGSI_WRITEMASK_X;
+		break;
+
+	/* TODO: I think we should ignore these?
+	case TGSI_TEXTURE_RECT:
+	case TGSI_TEXTURE_SHADOWRECT:
+	*/
+	}
+
+	/* sanity check.. driver could be asking to saturate a non-
+	 * existent coordinate component:
+	 */
+	if (!mask)
+		return -1;
+
+	/* MOV tmpA, src0 */
+	create_mov(tctx, &ctx->tmp[A].dst, coord, TGSI_WRITEMASK_XYZW, 0);
+
+	/* This is a bit sad.. we need to clamp *after* the coords
+	 * are projected, which means lowering TXP to TEX and doing
+	 * the projection ourself.  But since I haven't figured out
+	 * how to make the lowering code deliver an electric shock
+	 * to anyone using GL_CLAMP, we must do this instead:
+	 */
+	if (opcode == TGSI_OPCODE_TXP) {
+		/* RCP tmpB.x tmpA.w */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_RCP;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], &ctx->tmp[B].dst, TGSI_WRITEMASK_X);
+		new_inst.Instruction.NumSrcRegs = 1;
+		reg_src(&new_inst.Src[0], &ctx->tmp[A].src, SWIZ(W,_,_,_));
+		tctx->emit_instruction(tctx, &new_inst);
+
+		/* MUL tmpA.mask, tmpA, tmpB.xxxx */
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_MUL;
+		new_inst.Instruction.NumDstRegs = 1;
+		reg_dst(&new_inst.Dst[0], &ctx->tmp[A].dst, pmask);
+		new_inst.Instruction.NumSrcRegs = 2;
+		reg_src(&new_inst.Src[0], &ctx->tmp[A].src, SWIZ(X,Y,Z,W));
+		reg_src(&new_inst.Src[1], &ctx->tmp[B].src, SWIZ(X,X,X,X));
+		tctx->emit_instruction(tctx, &new_inst);
+
+		opcode = TGSI_OPCODE_TEX;
+	}
+
+	/* MOV_SAT tmpA.<mask>, tmpA */
+	create_mov(tctx, &ctx->tmp[A].dst, &ctx->tmp[A].src, mask,
+			TGSI_SAT_ZERO_ONE);
+
+	/* modify the texture samp instruction to take fixed up coord: */
+	new_inst = *inst;
+	new_inst.Instruction.Opcode = opcode;
+	new_inst.Src[0] = ctx->tmp[A].src;
+	tctx->emit_instruction(tctx, &new_inst);
+
+	return 0;
+}
+
+/* Two-sided color emulation:
+ * For each COLOR input, create a corresponding BCOLOR input, plus
+ * CMP instruction to select front or back color based on FACE
+ */
+#define TWOSIDE_GROW(n)  (                       \
+			2 +         /* FACE */               \
+			((n) * 2) + /* IN[] BCOLOR[n] */     \
+			((n) * 1) + /* TEMP[] */             \
+			((n) * NINST(3))   /* CMP instr */   \
+		)
+
+static void
+emit_twoside(struct tgsi_transform_context *tctx)
+{
+	struct fd_lowering_context *ctx = fd_lowering_context(tctx);
+	struct tgsi_shader_info *info = ctx->info;
+	struct tgsi_full_declaration decl;
+	struct tgsi_full_instruction new_inst;
+	unsigned inbase, tmpbase;
+	int i;
+
+	inbase  = info->file_max[TGSI_FILE_INPUT] + 1;
+	tmpbase = info->file_max[TGSI_FILE_TEMPORARY] + 1;
+
+	/* additional inputs for BCOLOR's */
+	for (i = 0; i < ctx->two_side_colors; i++) {
+		decl = tgsi_default_full_declaration();
+		decl.Declaration.File = TGSI_FILE_INPUT;
+		decl.Declaration.Semantic = true;
+		decl.Range.First = decl.Range.Last = inbase + i;
+		decl.Semantic.Name = TGSI_SEMANTIC_BCOLOR;
+		decl.Semantic.Index =
+			info->input_semantic_index[ctx->two_side_idx[i]];
+		tctx->emit_declaration(tctx, &decl);
+	}
+
+	/* additional input for FACE */
+	if (ctx->two_side_colors && (ctx->face_idx == -1)) {
+		decl = tgsi_default_full_declaration();
+		decl.Declaration.File = TGSI_FILE_INPUT;
+		decl.Declaration.Semantic = true;
+		decl.Range.First = decl.Range.Last = inbase + ctx->two_side_colors;
+		decl.Semantic.Name = TGSI_SEMANTIC_FACE;
+		decl.Semantic.Index = 0;
+		tctx->emit_declaration(tctx, &decl);
+
+		ctx->face_idx = decl.Range.First;
+	}
+
+	/* additional temps for COLOR/BCOLOR selection: */
+	for (i = 0; i < ctx->two_side_colors; i++) {
+		decl = tgsi_default_full_declaration();
+		decl.Declaration.File = TGSI_FILE_TEMPORARY;
+		decl.Range.First = decl.Range.Last = tmpbase + ctx->numtmp + i;
+		tctx->emit_declaration(tctx, &decl);
+	}
+
+	/* and finally additional instructions to select COLOR/BCOLOR: */
+	for (i = 0; i < ctx->two_side_colors; i++) {
+		new_inst = tgsi_default_full_instruction();
+		new_inst.Instruction.Opcode = TGSI_OPCODE_CMP;
+
+		new_inst.Instruction.NumDstRegs = 1;
+		new_inst.Dst[0].Register.File  = TGSI_FILE_TEMPORARY;
+		new_inst.Dst[0].Register.Index = tmpbase + ctx->numtmp + i;
+		new_inst.Dst[0].Register.WriteMask = TGSI_WRITEMASK_XYZW;
+
+		new_inst.Instruction.NumSrcRegs = 3;
+		new_inst.Src[0].Register.File  = TGSI_FILE_INPUT;
+		new_inst.Src[0].Register.Index = ctx->face_idx;
+		new_inst.Src[0].Register.SwizzleX = TGSI_SWIZZLE_X;
+		new_inst.Src[0].Register.SwizzleY = TGSI_SWIZZLE_X;
+		new_inst.Src[0].Register.SwizzleZ = TGSI_SWIZZLE_X;
+		new_inst.Src[0].Register.SwizzleW = TGSI_SWIZZLE_X;
+		new_inst.Src[1].Register.File  = TGSI_FILE_INPUT;
+		new_inst.Src[1].Register.Index = inbase + i;
+		new_inst.Src[1].Register.SwizzleX = TGSI_SWIZZLE_X;
+		new_inst.Src[1].Register.SwizzleY = TGSI_SWIZZLE_Y;
+		new_inst.Src[1].Register.SwizzleZ = TGSI_SWIZZLE_Z;
+		new_inst.Src[1].Register.SwizzleW = TGSI_SWIZZLE_W;
+		new_inst.Src[2].Register.File  = TGSI_FILE_INPUT;
+		new_inst.Src[2].Register.Index = ctx->two_side_idx[i];
+		new_inst.Src[2].Register.SwizzleX = TGSI_SWIZZLE_X;
+		new_inst.Src[2].Register.SwizzleY = TGSI_SWIZZLE_Y;
+		new_inst.Src[2].Register.SwizzleZ = TGSI_SWIZZLE_Z;
+		new_inst.Src[2].Register.SwizzleW = TGSI_SWIZZLE_W;
+
+		tctx->emit_instruction(tctx, &new_inst);
+	}
+}
+
+static void
+emit_decls(struct tgsi_transform_context *tctx)
+{
+	struct fd_lowering_context *ctx = fd_lowering_context(tctx);
+	struct tgsi_shader_info *info = ctx->info;
+	struct tgsi_full_declaration decl;
+	struct tgsi_full_immediate immed;
+	unsigned tmpbase;
+	int i;
+
+	tmpbase = info->file_max[TGSI_FILE_TEMPORARY] + 1;
+
+	ctx->color_base = tmpbase + ctx->numtmp;
+
+	/* declare immediate: */
+	immed = tgsi_default_full_immediate();
+	immed.Immediate.NrTokens = 1 + 4; /* one for the token itself */
+	immed.u[0].Float = 0.0;
+	immed.u[1].Float = 1.0;
+	immed.u[2].Float = 128.0;
+	immed.u[3].Float = 0.0;
+	tctx->emit_immediate(tctx, &immed);
+
+	ctx->imm.Register.File = TGSI_FILE_IMMEDIATE;
+	ctx->imm.Register.Index = info->immediate_count;
+	ctx->imm.Register.SwizzleX = TGSI_SWIZZLE_X;
+	ctx->imm.Register.SwizzleY = TGSI_SWIZZLE_Y;
+	ctx->imm.Register.SwizzleZ = TGSI_SWIZZLE_Z;
+	ctx->imm.Register.SwizzleW = TGSI_SWIZZLE_W;
+
+	/* declare temp regs: */
+	for (i = 0; i < ctx->numtmp; i++) {
+		decl = tgsi_default_full_declaration();
+		decl.Declaration.File = TGSI_FILE_TEMPORARY;
+		decl.Range.First = decl.Range.Last = tmpbase + i;
+		tctx->emit_declaration(tctx, &decl);
+
+		ctx->tmp[i].src.Register.File  = TGSI_FILE_TEMPORARY;
+		ctx->tmp[i].src.Register.Index = tmpbase + i;
+		ctx->tmp[i].src.Register.SwizzleX = TGSI_SWIZZLE_X;
+		ctx->tmp[i].src.Register.SwizzleY = TGSI_SWIZZLE_Y;
+		ctx->tmp[i].src.Register.SwizzleZ = TGSI_SWIZZLE_Z;
+		ctx->tmp[i].src.Register.SwizzleW = TGSI_SWIZZLE_W;
+
+		ctx->tmp[i].dst.Register.File  = TGSI_FILE_TEMPORARY;
+		ctx->tmp[i].dst.Register.Index = tmpbase + i;
+		ctx->tmp[i].dst.Register.WriteMask = TGSI_WRITEMASK_XYZW;
+	}
+
+	if (ctx->two_side_colors)
+		emit_twoside(tctx);
+}
+
+static void
+rename_color_inputs(struct fd_lowering_context *ctx,
+		struct tgsi_full_instruction *inst)
+{
+	unsigned i, j;
+	for (i = 0; i < inst->Instruction.NumSrcRegs; i++) {
+		struct tgsi_src_register *src = &inst->Src[i].Register;
+		if (src->File == TGSI_FILE_INPUT) {
+			for (j = 0; j < ctx->two_side_colors; j++) {
+				if (src->Index == ctx->two_side_idx[j]) {
+					src->File = TGSI_FILE_TEMPORARY;
+					src->Index = ctx->color_base + j;
+					break;
+				}
+			}
+		}
+	}
+
+}
+
+static void
+transform_instr(struct tgsi_transform_context *tctx,
+		struct tgsi_full_instruction *inst)
+{
+	struct fd_lowering_context *ctx = fd_lowering_context(tctx);
+
+	if (!ctx->emitted_decls) {
+		emit_decls(tctx);
+		ctx->emitted_decls = 1;
+	}
+
+	/* if emulating two-sided-color, we need to re-write some
+	 * src registers:
+	 */
+	if (ctx->two_side_colors)
+		rename_color_inputs(ctx, inst);
+
+	switch (inst->Instruction.Opcode) {
+	case TGSI_OPCODE_DST:
+		if (!ctx->config->lower_DST)
+			goto skip;
+		transform_dst(tctx, inst);
+		break;
+	case TGSI_OPCODE_XPD:
+		if (!ctx->config->lower_XPD)
+			goto skip;
+		transform_xpd(tctx, inst);
+		break;
+	case TGSI_OPCODE_SCS:
+		if (!ctx->config->lower_SCS)
+			goto skip;
+		transform_scs(tctx, inst);
+		break;
+	case TGSI_OPCODE_LRP:
+		if (!ctx->config->lower_LRP)
+			goto skip;
+		transform_lrp(tctx, inst);
+		break;
+	case TGSI_OPCODE_FRC:
+		if (!ctx->config->lower_FRC)
+			goto skip;
+		transform_frc(tctx, inst);
+		break;
+	case TGSI_OPCODE_POW:
+		if (!ctx->config->lower_POW)
+			goto skip;
+		transform_pow(tctx, inst);
+		break;
+	case TGSI_OPCODE_LIT:
+		if (!ctx->config->lower_LIT)
+			goto skip;
+		transform_lit(tctx, inst);
+		break;
+	case TGSI_OPCODE_EXP:
+		if (!ctx->config->lower_EXP)
+			goto skip;
+		transform_exp(tctx, inst);
+		break;
+	case TGSI_OPCODE_LOG:
+		if (!ctx->config->lower_LOG)
+			goto skip;
+		transform_log(tctx, inst);
+		break;
+	case TGSI_OPCODE_DP4:
+		if (!ctx->config->lower_DP4)
+			goto skip;
+		transform_dotp(tctx, inst);
+		break;
+	case TGSI_OPCODE_DP3:
+		if (!ctx->config->lower_DP3)
+			goto skip;
+		transform_dotp(tctx, inst);
+		break;
+	case TGSI_OPCODE_DPH:
+		if (!ctx->config->lower_DPH)
+			goto skip;
+		transform_dotp(tctx, inst);
+		break;
+	case TGSI_OPCODE_DP2:
+		if (!ctx->config->lower_DP2)
+			goto skip;
+		transform_dotp(tctx, inst);
+		break;
+	case TGSI_OPCODE_DP2A:
+		if (!ctx->config->lower_DP2A)
+			goto skip;
+		transform_dotp(tctx, inst);
+		break;
+	case TGSI_OPCODE_TEX:
+	case TGSI_OPCODE_TXP:
+	case TGSI_OPCODE_TXB:
+	case TGSI_OPCODE_TXB2:
+	case TGSI_OPCODE_TXL:
+		if (transform_samp(tctx, inst))
+			goto skip;
+		break;
+	default:
+	skip:
+		tctx->emit_instruction(tctx, inst);
+		break;
+	}
+}
+
+/* returns NULL if no lowering required, else returns the new
+ * tokens (which caller is required to free()).  In either case
+ * returns the current info.
+ */
+const struct tgsi_token *
+fd_transform_lowering(const struct fd_lowering_config *config,
+		const struct tgsi_token *tokens,
+		struct tgsi_shader_info *info)
+{
+	struct fd_lowering_context ctx;
+	struct tgsi_token *newtoks;
+	int newlen, numtmp;
+
+	/* sanity check in case limit is ever increased: */
+	assert((sizeof(config->saturate_s) * 8) >= PIPE_MAX_SAMPLERS);
+
+	memset(&ctx, 0, sizeof(ctx));
+	ctx.base.transform_instruction = transform_instr;
+	ctx.info = info;
+	ctx.config = config;
+
+	tgsi_scan_shader(tokens, info);
+
+	/* if we are adding fragment shader support to emulate two-sided
+	 * color, then figure out the number of additional inputs we need
+	 * to create for BCOLOR's..
+	 */
+	if ((info->processor == TGSI_PROCESSOR_FRAGMENT) &&
+			config->color_two_side) {
+		int i;
+		ctx.face_idx = -1;
+		for (i = 0; i <= info->file_max[TGSI_FILE_INPUT]; i++) {
+			if (info->input_semantic_name[i] == TGSI_SEMANTIC_COLOR)
+				ctx.two_side_idx[ctx.two_side_colors++] = i;
+			if (info->input_semantic_name[i] == TGSI_SEMANTIC_FACE)
+				ctx.face_idx = i;
+		}
+	}
+
+	ctx.saturate = config->saturate_r | config->saturate_s | config->saturate_t;
+
+#define OPCS(x) ((config->lower_ ## x) ? info->opcode_count[TGSI_OPCODE_ ## x] : 0)
+	/* if there are no instructions to lower, then we are done: */
+	if (!(OPCS(DST) ||
+			OPCS(XPD) ||
+			OPCS(SCS) ||
+			OPCS(LRP) ||
+			OPCS(FRC) ||
+			OPCS(POW) ||
+			OPCS(LIT) ||
+			OPCS(EXP) ||
+			OPCS(LOG) ||
+			OPCS(DP4) ||
+			OPCS(DP3) ||
+			OPCS(DPH) ||
+			OPCS(DP2) ||
+			OPCS(DP2A) ||
+			ctx.two_side_colors ||
+			ctx.saturate))
+		return NULL;
+
+#if 0  /* debug */
+	_debug_printf("BEFORE:");
+	tgsi_dump(tokens, 0);
+#endif
+
+	numtmp = 0;
+	newlen = tgsi_num_tokens(tokens);
+	if (OPCS(DST)) {
+		newlen += DST_GROW * OPCS(DST);
+		numtmp = MAX2(numtmp, DST_TMP);
+	}
+	if (OPCS(XPD)) {
+		newlen += XPD_GROW * OPCS(XPD);
+		numtmp = MAX2(numtmp, XPD_TMP);
+	}
+	if (OPCS(SCS)) {
+		newlen += SCS_GROW * OPCS(SCS);
+		numtmp = MAX2(numtmp, SCS_TMP);
+	}
+	if (OPCS(LRP)) {
+		newlen += LRP_GROW * OPCS(LRP);
+		numtmp = MAX2(numtmp, LRP_TMP);
+	}
+	if (OPCS(FRC)) {
+		newlen += FRC_GROW * OPCS(FRC);
+		numtmp = MAX2(numtmp, FRC_TMP);
+	}
+	if (OPCS(POW)) {
+		newlen += POW_GROW * OPCS(POW);
+		numtmp = MAX2(numtmp, POW_TMP);
+	}
+	if (OPCS(LIT)) {
+		newlen += LIT_GROW * OPCS(LIT);
+		numtmp = MAX2(numtmp, LIT_TMP);
+	}
+	if (OPCS(EXP)) {
+		newlen += EXP_GROW * OPCS(EXP);
+		numtmp = MAX2(numtmp, EXP_TMP);
+	}
+	if (OPCS(LOG)) {
+		newlen += LOG_GROW * OPCS(LOG);
+		numtmp = MAX2(numtmp, LOG_TMP);
+	}
+	if (OPCS(DP4)) {
+		newlen += DP4_GROW * OPCS(DP4);
+		numtmp = MAX2(numtmp, DOTP_TMP);
+	}
+	if (OPCS(DP3)) {
+		newlen += DP3_GROW * OPCS(DP3);
+		numtmp = MAX2(numtmp, DOTP_TMP);
+	}
+	if (OPCS(DPH)) {
+		newlen += DPH_GROW * OPCS(DPH);
+		numtmp = MAX2(numtmp, DOTP_TMP);
+	}
+	if (OPCS(DP2)) {
+		newlen += DP2_GROW * OPCS(DP2);
+		numtmp = MAX2(numtmp, DOTP_TMP);
+	}
+	if (OPCS(DP2A)) {
+		newlen += DP2A_GROW * OPCS(DP2A);
+		numtmp = MAX2(numtmp, DOTP_TMP);
+	}
+	if (ctx.saturate) {
+		int n = info->opcode_count[TGSI_OPCODE_TEX] +
+			info->opcode_count[TGSI_OPCODE_TXP] +
+			info->opcode_count[TGSI_OPCODE_TXB] +
+			info->opcode_count[TGSI_OPCODE_TXB2] +
+			info->opcode_count[TGSI_OPCODE_TXL];
+		newlen += SAMP_GROW * n;
+		numtmp = MAX2(numtmp, SAMP_TMP);
+	}
+
+	/* specifically don't include two_side_colors temps in the count: */
+	ctx.numtmp = numtmp;
+
+	if (ctx.two_side_colors) {
+		newlen += TWOSIDE_GROW(ctx.two_side_colors);
+		/* note: we permanently consume temp regs, re-writing references
+		 * to IN.COLOR[n] to TEMP[m] (holding the output of of the CMP
+		 * instruction that selects which varying to use):
+		 */
+		numtmp += ctx.two_side_colors;
+	}
+
+	newlen += 2 * numtmp;
+	newlen += 5;        /* immediate */
+
+	newtoks = tgsi_alloc_tokens(newlen);
+	if (!newtoks)
+		return NULL;
+
+	tgsi_transform_shader(tokens, newtoks, newlen, &ctx.base);
+
+	tgsi_scan_shader(newtoks, info);
+
+#if 0  /* debug */
+	_debug_printf("AFTER:");
+	tgsi_dump(newtoks, 0);
+#endif
+
+	return newtoks;
+}
diff --git a/src/gallium/auxiliary/tgsi/tgsi_lowering.h b/src/gallium/auxiliary/tgsi/tgsi_lowering.h
new file mode 100644
index 00000000000..1b0daa96f0e
--- /dev/null
+++ b/src/gallium/auxiliary/tgsi/tgsi_lowering.h
@@ -0,0 +1,89 @@
+/* -*- mode: C; c-file-style: "k&r"; tab-width 4; indent-tabs-mode: t; -*- */
+
+/*
+ * Copyright (C) 2014 Rob Clark <[email protected]>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *
+ * Authors:
+ *    Rob Clark <[email protected]>
+ */
+
+#ifndef FREEDRENO_LOWERING_H_
+#define FREEDRENO_LOWERING_H_
+
+#include "pipe/p_shader_tokens.h"
+#include "tgsi/tgsi_scan.h"
+
+struct fd_lowering_config {
+	/* For fragment shaders, generate a shader that emulates two
+	 * sided color by inserting a BGCOLOR input for each COLOR
+	 * input, and insert a CMP instruction to select the correct
+	 * color to use based on the TGSI_SEMANTIC_FACE input.
+	 *
+	 * Note that drivers which use this to emulate two sided color
+	 * will:
+	 *  a) need to generate (on demand) alternate shaders to use
+	 *     depending on the rasterizer state (ie. whether two
+	 *     sided shading enabled)
+	 *  b) expect to see the BGCOLOR semantic name in fragment
+	 *     shaders.  During linkage, the driver should simply
+	 *     map VS.OUT.BGCOLOR[n] to FS.IN.BGCOLOR[n] (in the
+	 *     same was as linking other outs/ins).
+	 */
+	unsigned color_two_side : 1;
+
+	/* TODO support for alpha_to_one as well?? */
+
+	/* Individual OPC lowerings, if lower_<opc> is TRUE then
+	 * enable lowering of TGSI_OPCODE_<opc>
+	 */
+	unsigned lower_DST : 1;
+	unsigned lower_XPD : 1;
+	unsigned lower_SCS : 1;
+	unsigned lower_LRP : 1;
+	unsigned lower_FRC : 1;
+	unsigned lower_POW : 1;
+	unsigned lower_LIT : 1;
+	unsigned lower_EXP : 1;
+	unsigned lower_LOG : 1;
+	unsigned lower_DP4 : 1;
+	unsigned lower_DP3 : 1;
+	unsigned lower_DPH : 1;
+	unsigned lower_DP2 : 1;
+	unsigned lower_DP2A : 1;
+
+	/* To emulate certain texture wrap modes, this can be used
+	 * to saturate the specified tex coord to [0.0, 1.0].  The
+	 * bits are according to sampler #, ie. if, for example:
+	 *
+	 *   (conf->saturate_s & (1 << n))
+	 *
+	 * is true, then the s coord for sampler n is saturated.
+	 */
+	unsigned saturate_s, saturate_t, saturate_r;
+};
+
+const struct tgsi_token * fd_transform_lowering(
+		const struct fd_lowering_config *config,
+		const struct tgsi_token *tokens,
+		struct tgsi_shader_info *info);
+
+#endif /* FREEDRENO_LOWERING_H_ */