ac/llvm: use min+max instead of AMDGPU.clamp on LLVM 5.0

It selects v_med3_f32, which has the same rate & size.

Reviewed-by: Dave Airlie <airlied@redhat.com>
Reviewed-by: Nicolai Hähnle <nicolai.haehnle@amd.com>

diff --git a/src/amd/common/ac_llvm_build.c b/src/amd/common/ac_llvm_build.c
index 351ff88306e276346416a12a93e19a18eb2b1d1c..2f25b1400e8732ebe3048e9f877ec9fca73292d5 100644 (file)
--- a/src/amd/common/ac_llvm_build.c
+++ b/src/amd/common/ac_llvm_build.c
@@ -817,6 +817,23 @@ ac_emit_umsb(struct ac_llvm_context *ctx,
 
 LLVMValueRef ac_emit_clamp(struct ac_llvm_context *ctx, LLVMValueRef value)
 {
+       if (HAVE_LLVM >= 0x0500) {
+               LLVMValueRef max[2] = {
+                       value,
+                       LLVMConstReal(ctx->f32, 0),
+               };
+               LLVMValueRef min[2] = {
+                       LLVMConstReal(ctx->f32, 1),
+               };
+
+               min[1] = ac_emit_llvm_intrinsic(ctx, "llvm.maxnum.f32",
+                                               ctx->f32, max, 2,
+                                               AC_FUNC_ATTR_READNONE);
+               return ac_emit_llvm_intrinsic(ctx, "llvm.minnum.f32",
+                                             ctx->f32, min, 2,
+                                             AC_FUNC_ATTR_READNONE);
+       }
+
        const char *intr = HAVE_LLVM >= 0x0308 ? "llvm.AMDGPU.clamp." :
                                                 "llvm.AMDIL.clamp.";
        LLVMValueRef args[3] = {