From fadfaa82c61a32c74531e1e1aaecfd2b3c5ac6d8 Mon Sep 17 00:00:00 2001 From: Russell King Date: Wed, 13 Apr 2016 18:42:42 -0400 Subject: tgsi/lowering: improved lowering for LRP Provide an improved lowering for LRP, which can be implemented in two MAD instructions with a bit of rearranging of the equation, rather than the literal implementation of two multiplies, an add and a subtract. Signed-off-by: Russell King Reviewed-by: Rob Clark Signed-off-by: Rob Clark --- src/gallium/auxiliary/tgsi/tgsi_lowering.c | 55 +++++++++++------------------- 1 file changed, 20 insertions(+), 35 deletions(-) (limited to 'src/gallium') diff --git a/src/gallium/auxiliary/tgsi/tgsi_lowering.c b/src/gallium/auxiliary/tgsi/tgsi_lowering.c index 2a991589352..d54f4b91bb1 100644 --- a/src/gallium/auxiliary/tgsi/tgsi_lowering.c +++ b/src/gallium/auxiliary/tgsi/tgsi_lowering.c @@ -388,14 +388,15 @@ transform_scs(struct tgsi_transform_context *tctx, * 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 + * This becomes: src0 \times src1 + src2 - src0 \times src2, which + * can then become: src0 \times src1 - (src0 \times src2 - src2) + * + * ; needs: 1 tmp + * MAD tmpA, src0, src2, -src2 + * MAD dst, src0, src1, -tmpA */ -#define LRP_GROW (NINST(2) + NINST(2) + NINST(2) + NINST(2) - OINST(3)) -#define LRP_TMP 2 +#define LRP_GROW (NINST(3) + NINST(3) - OINST(3)) +#define LRP_TMP 1 static void transform_lrp(struct tgsi_transform_context *tctx, struct tgsi_full_instruction *inst) @@ -408,44 +409,28 @@ transform_lrp(struct tgsi_transform_context *tctx, struct tgsi_full_instruction new_inst; if (dst->Register.WriteMask & TGSI_WRITEMASK_XYZW) { - /* MUL tmpA, src0, src1 */ + /* MAD tmpA, src0, src2, -src2 */ new_inst = tgsi_default_full_instruction(); - new_inst.Instruction.Opcode = TGSI_OPCODE_MUL; + new_inst.Instruction.Opcode = TGSI_OPCODE_MAD; new_inst.Instruction.NumDstRegs = 1; reg_dst(&new_inst.Dst[0], &ctx->tmp[A].dst, TGSI_WRITEMASK_XYZW); - new_inst.Instruction.NumSrcRegs = 2; + new_inst.Instruction.NumSrcRegs = 3; 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)); + reg_src(&new_inst.Src[2], src2, SWIZ(X, Y, Z, W)); + new_inst.Src[2].Register.Negate = !new_inst.Src[2].Register.Negate; tctx->emit_instruction(tctx, &new_inst); - /* ADD dst, tmpA, tmpB */ + /* MAD dst, src0, src1, -tmpA */ new_inst = tgsi_default_full_instruction(); - new_inst.Instruction.Opcode = TGSI_OPCODE_ADD; + new_inst.Instruction.Opcode = TGSI_OPCODE_MAD; 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)); + new_inst.Instruction.NumSrcRegs = 3; + reg_src(&new_inst.Src[0], src0, SWIZ(X, Y, Z, W)); + reg_src(&new_inst.Src[1], src1, SWIZ(X, Y, Z, W)); + reg_src(&new_inst.Src[2], &ctx->tmp[A].src, SWIZ(X, Y, Z, W)); + new_inst.Src[2].Register.Negate = true; tctx->emit_instruction(tctx, &new_inst); } } -- cgit v1.2.3