[Mesa-dev] [PATCH] ac/nir: use llvm fma intrinsic if nir instruction is exact.

[Dave Airlie]

From: Dave Airlie <airlied at redhat.com>

As pointed out by Connor we still need to use fma if nir wants
exact (precise) behaviour.

Signed-off-by: Dave Airlie <airlied at redhat.com>
---
 src/amd/common/ac_nir_to_llvm.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/amd/common/ac_nir_to_llvm.c b/src/amd/common/ac_nir_to_llvm.c
index 11ba487..38a2bbe 100644
--- a/src/amd/common/ac_nir_to_llvm.c
+++ b/src/amd/common/ac_nir_to_llvm.c
@@ -1707,7 +1707,7 @@ static void visit_alu(struct ac_nir_context *ctx, const nir_alu_instr *instr)
 						      result);
 		break;
 	case nir_op_ffma:
-		result = emit_intrin_3f_param(&ctx->ac, "llvm.fmuladd",
+		result = emit_intrin_3f_param(&ctx->ac, instr->exact ? "llvm.fma" : "llvm.fmuladd",
 		                              ac_to_float_type(&ctx->ac, def_type), src[0], src[1], src[2]);
 		break;
 	case nir_op_ibitfield_extract:
-- 
2.9.5