[Mesa-dev] [PATCH 1/4] r600: use min_dx10/max_dx10 instead of min/max

[sroland at vmware.com]

From: Roland Scheidegger <sroland at vmware.com>

I believe this is the safe thing to do, especially ever since the driver
actually generates NaNs for muls too.
Albeit since the radeon ISA docs are inaccurate/wrong there, I'm not
entirely sure what the non-dx10 versions do, but (as required by dx10)
the dx10 versions should pick a non-nan source over a nan source.
Other drivers presumably do the same (radeonsi, llvmpipe).
This was shown to make some difference for bug 103544, albeit it is not
required to fix it.
---
 src/gallium/drivers/r600/r600_shader.c  | 12 ++++++------
 src/gallium/drivers/r600/sb/sb_expr.cpp |  2 ++
 2 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/src/gallium/drivers/r600/r600_shader.c b/src/gallium/drivers/r600/r600_shader.c
index 188fbc9d47..6a755bb3fd 100644
--- a/src/gallium/drivers/r600/r600_shader.c
+++ b/src/gallium/drivers/r600/r600_shader.c
@@ -8844,8 +8844,8 @@ static const struct r600_shader_tgsi_instruction r600_shader_tgsi_instruction[]
 	[TGSI_OPCODE_DP3]	= { ALU_OP2_DOT4_IEEE, tgsi_dp},
 	[TGSI_OPCODE_DP4]	= { ALU_OP2_DOT4_IEEE, tgsi_dp},
 	[TGSI_OPCODE_DST]	= { ALU_OP0_NOP, tgsi_opdst},
-	[TGSI_OPCODE_MIN]	= { ALU_OP2_MIN, tgsi_op2},
-	[TGSI_OPCODE_MAX]	= { ALU_OP2_MAX, tgsi_op2},
+	[TGSI_OPCODE_MIN]	= { ALU_OP2_MIN_DX10, tgsi_op2},
+	[TGSI_OPCODE_MAX]	= { ALU_OP2_MAX_DX10, tgsi_op2},
 	[TGSI_OPCODE_SLT]	= { ALU_OP2_SETGT, tgsi_op2_swap},
 	[TGSI_OPCODE_SGE]	= { ALU_OP2_SETGE, tgsi_op2},
 	[TGSI_OPCODE_MAD]	= { ALU_OP3_MULADD_IEEE, tgsi_op3},
@@ -9042,8 +9042,8 @@ static const struct r600_shader_tgsi_instruction eg_shader_tgsi_instruction[] =
 	[TGSI_OPCODE_DP3]	= { ALU_OP2_DOT4_IEEE, tgsi_dp},
 	[TGSI_OPCODE_DP4]	= { ALU_OP2_DOT4_IEEE, tgsi_dp},
 	[TGSI_OPCODE_DST]	= { ALU_OP0_NOP, tgsi_opdst},
-	[TGSI_OPCODE_MIN]	= { ALU_OP2_MIN, tgsi_op2},
-	[TGSI_OPCODE_MAX]	= { ALU_OP2_MAX, tgsi_op2},
+	[TGSI_OPCODE_MIN]	= { ALU_OP2_MIN_DX10, tgsi_op2},
+	[TGSI_OPCODE_MAX]	= { ALU_OP2_MAX_DX10, tgsi_op2},
 	[TGSI_OPCODE_SLT]	= { ALU_OP2_SETGT, tgsi_op2_swap},
 	[TGSI_OPCODE_SGE]	= { ALU_OP2_SETGE, tgsi_op2},
 	[TGSI_OPCODE_MAD]	= { ALU_OP3_MULADD_IEEE, tgsi_op3},
@@ -9265,8 +9265,8 @@ static const struct r600_shader_tgsi_instruction cm_shader_tgsi_instruction[] =
 	[TGSI_OPCODE_DP3]	= { ALU_OP2_DOT4_IEEE, tgsi_dp},
 	[TGSI_OPCODE_DP4]	= { ALU_OP2_DOT4_IEEE, tgsi_dp},
 	[TGSI_OPCODE_DST]	= { ALU_OP0_NOP, tgsi_opdst},
-	[TGSI_OPCODE_MIN]	= { ALU_OP2_MIN, tgsi_op2},
-	[TGSI_OPCODE_MAX]	= { ALU_OP2_MAX, tgsi_op2},
+	[TGSI_OPCODE_MIN]	= { ALU_OP2_MIN_DX10, tgsi_op2},
+	[TGSI_OPCODE_MAX]	= { ALU_OP2_MAX_DX10, tgsi_op2},
 	[TGSI_OPCODE_SLT]	= { ALU_OP2_SETGT, tgsi_op2_swap},
 	[TGSI_OPCODE_SGE]	= { ALU_OP2_SETGE, tgsi_op2},
 	[TGSI_OPCODE_MAD]	= { ALU_OP3_MULADD_IEEE, tgsi_op3},
diff --git a/src/gallium/drivers/r600/sb/sb_expr.cpp b/src/gallium/drivers/r600/sb/sb_expr.cpp
index 3dd3a4815b..7a5d62c8e8 100644
--- a/src/gallium/drivers/r600/sb/sb_expr.cpp
+++ b/src/gallium/drivers/r600/sb/sb_expr.cpp
@@ -753,7 +753,9 @@ bool expr_handler::fold_alu_op2(alu_node& n) {
 				n.bc.src[0].abs == n.bc.src[1].abs) {
 			switch (n.bc.op) {
 			case ALU_OP2_MIN: // (MIN x, x) => (MOV x)
+			case ALU_OP2_MIN_DX10:
 			case ALU_OP2_MAX:
+			case ALU_OP2_MAX_DX10:
 				convert_to_mov(n, v0, n.bc.src[0].neg, n.bc.src[0].abs);
 				return fold_alu_op1(n);
 			case ALU_OP2_ADD:  // (ADD x, x) => (MUL x, 2)
-- 
2.12.3