[Mesa-dev] [PATCH v3 10/10] nv50/ir: disable mul+add to mad for precise instructions

[Karol Herbst]

fixes
    missrendering in TombRaider
    KHR-GL44.gpu_shader5.precise_qualifier
    KHR-GL45.gpu_shader5.precise_qualifier

Signed-off-by: Karol Herbst <karolherbst at gmail.com>
---
 src/gallium/drivers/nouveau/codegen/nv50_ir_peephole.cpp | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/gallium/drivers/nouveau/codegen/nv50_ir_peephole.cpp b/src/gallium/drivers/nouveau/codegen/nv50_ir_peephole.cpp
index 4c92a1efb5..85f3f44832 100644
--- a/src/gallium/drivers/nouveau/codegen/nv50_ir_peephole.cpp
+++ b/src/gallium/drivers/nouveau/codegen/nv50_ir_peephole.cpp
@@ -1669,6 +1669,10 @@ AlgebraicOpt::handleABS(Instruction *abs)
 bool
 AlgebraicOpt::handleADD(Instruction *add)
 {
+   // we can't optimize to SAD/MAD if the instruction is tagged as precise
+   if (add->precise)
+      return false;
+
    Value *src0 = add->getSrc(0);
    Value *src1 = add->getSrc(1);
 
@@ -1712,7 +1716,7 @@ AlgebraicOpt::tryADDToMADOrSAD(Instruction *add, operation toOp)
       return false;
 
    if (src->getInsn()->saturate || src->getInsn()->postFactor ||
-       src->getInsn()->dnz)
+       src->getInsn()->dnz || src->getInsn()->precise)
       return false;
 
    if (toOp == OP_SAD) {
-- 
2.13.1