From a55e50b082ca068d35d695ff323603507e2b64aa Mon Sep 17 00:00:00 2001
From: Luca Barbieri <luca@luca-barbieri.com>
Date: Sat, 26 Dec 2009 08:12:15 +0100
Subject: [PATCH] NV30/NV40 CMP and SCS src == dst handling

CMP and SCS can produce incorrect results if the source and
destination are the same.
This patch should fix the issues.
CMP is fixed by predicating both moves.
SCS by changing the order if the source component is X.
---
 src/gallium/drivers/nv30/nv30_fragprog.c | 32 ++++++++++++++++++------
 src/gallium/drivers/nv40/nv40_fragprog.c | 32 ++++++++++++++++++------
 2 files changed, 48 insertions(+), 16 deletions(-)

diff --git a/src/gallium/drivers/nv30/nv30_fragprog.c b/src/gallium/drivers/nv30/nv30_fragprog.c
index 40965a97723..dc4e583ce9d 100644
--- a/src/gallium/drivers/nv30/nv30_fragprog.c
+++ b/src/gallium/drivers/nv30/nv30_fragprog.c
@@ -435,10 +435,11 @@ nv30_fragprog_parse_instruction(struct nv30_fpc *fpc,
 		arith(fpc, sat, ADD, dst, mask, src[0], src[1], none);
 		break;
 	case TGSI_OPCODE_CMP:
-		tmp = temp(fpc);
-		arith(fpc, sat, MOV, dst, mask, src[2], none, none);
+		tmp = nv30_sr(NV30SR_NONE, 0);
 		tmp.cc_update = 1;
 		arith(fpc, 0, MOV, tmp, 0xf, src[0], none, none);
+		dst.cc_test = NV30_VP_INST_COND_GE;
+		arith(fpc, sat, MOV, dst, mask, src[2], none, none);
 		dst.cc_test = NV30_VP_INST_COND_LT;
 		arith(fpc, sat, MOV, dst, mask, src[1], none, none);
 		break;
@@ -517,13 +518,28 @@ nv30_fragprog_parse_instruction(struct nv30_fpc *fpc,
 		arith(fpc, sat, RSQ, dst, mask, abs(swz(src[0], X, X, X, X)), none, none);
 		break;
 	case TGSI_OPCODE_SCS:
-		if (mask & MASK_X) {
-			arith(fpc, sat, COS, dst, MASK_X,
-			      swz(src[0], X, X, X, X), none, none);
+		/* avoid overwriting the source */
+		if(src[0].swz[SWZ_X] != SWZ_X)
+		{
+			if (mask & MASK_X) {
+				arith(fpc, sat, COS, dst, MASK_X,
+				      swz(src[0], X, X, X, X), none, none);
+			}
+			if (mask & MASK_Y) {
+				arith(fpc, sat, SIN, dst, MASK_Y,
+				      swz(src[0], X, X, X, X), none, none);
+			}
 		}
-		if (mask & MASK_Y) {
-			arith(fpc, sat, SIN, dst, MASK_Y,
-			      swz(src[0], X, X, X, X), none, none);
+		else
+		{
+			if (mask & MASK_Y) {
+				arith(fpc, sat, SIN, dst, MASK_Y,
+				      swz(src[0], X, X, X, X), none, none);
+			}
+			if (mask & MASK_X) {
+				arith(fpc, sat, COS, dst, MASK_X,
+				      swz(src[0], X, X, X, X), none, none);
+			}
 		}
 		break;
 	case TGSI_OPCODE_SIN:
diff --git a/src/gallium/drivers/nv40/nv40_fragprog.c b/src/gallium/drivers/nv40/nv40_fragprog.c
index 1bf16726d10..468d3509a98 100644
--- a/src/gallium/drivers/nv40/nv40_fragprog.c
+++ b/src/gallium/drivers/nv40/nv40_fragprog.c
@@ -445,10 +445,11 @@ nv40_fragprog_parse_instruction(struct nv40_fpc *fpc,
 		arith(fpc, sat, ADD, dst, mask, src[0], src[1], none);
 		break;
 	case TGSI_OPCODE_CMP:
-		tmp = temp(fpc);
-		arith(fpc, sat, MOV, dst, mask, src[2], none, none);
+		tmp = nv40_sr(NV40SR_NONE, 0);
 		tmp.cc_update = 1;
 		arith(fpc, 0, MOV, tmp, 0xf, src[0], none, none);
+		dst.cc_test = NV40_VP_INST_COND_GE;
+		arith(fpc, sat, MOV, dst, mask, src[2], none, none);
 		dst.cc_test = NV40_VP_INST_COND_LT;
 		arith(fpc, sat, MOV, dst, mask, src[1], none, none);
 		break;
@@ -573,13 +574,28 @@ nv40_fragprog_parse_instruction(struct nv40_fpc *fpc,
 		      neg(swz(tmp, X, X, X, X)), none, none);
 		break;
 	case TGSI_OPCODE_SCS:
-		if (mask & MASK_X) {
-			arith(fpc, sat, COS, dst, MASK_X,
-			      swz(src[0], X, X, X, X), none, none);
+		/* avoid overwriting the source */
+		if(src[0].swz[SWZ_X] != SWZ_X)
+		{
+			if (mask & MASK_X) {
+				arith(fpc, sat, COS, dst, MASK_X,
+				      swz(src[0], X, X, X, X), none, none);
+			}
+			if (mask & MASK_Y) {
+				arith(fpc, sat, SIN, dst, MASK_Y,
+				      swz(src[0], X, X, X, X), none, none);
+			}
 		}
-		if (mask & MASK_Y) {
-			arith(fpc, sat, SIN, dst, MASK_Y,
-			      swz(src[0], X, X, X, X), none, none);
+		else
+		{
+			if (mask & MASK_Y) {
+				arith(fpc, sat, SIN, dst, MASK_Y,
+				      swz(src[0], X, X, X, X), none, none);
+			}
+			if (mask & MASK_X) {
+				arith(fpc, sat, COS, dst, MASK_X,
+				      swz(src[0], X, X, X, X), none, none);
+			}
 		}
 		break;
 	case TGSI_OPCODE_SEQ:
-- 
2.30.2