[clang] [llvm] Adding splitdouble HLSL function (PR #109331)

[Farzon Lotfi via cfe-commits]

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@@ -0,0 +1,34 @@
+// RUN: %clang_cc1 -finclude-default-header -x hlsl -triple dxil-pc-shadermodel6.3-library %s -fnative-half-type -emit-llvm -O1 -o - | FileCheck %s
+// RUN: %clang_cc1 -finclude-default-header -x hlsl -triple spirv--vulkan-library %s -fnative-half-type -emit-llvm -disable-llvm-passes -o - | FileCheck %s --check-prefix=SPIRV
+
+
+
+// CHECK: define {{.*}} float {{.*}}test_scalar{{.*}}(double {{.*}} [[VALD:%.*]])
+// CHECK: [[VALRET:%hlsl.asuint.*]] = {{.*}} call { i32, i32 } @llvm.dx.splitdouble.i32(double [[VALD]])
+// CHECK-NEXT: extractvalue { i32, i32 } [[VALRET]], 0
+// CHECK-NEXT: extractvalue { i32, i32 } [[VALRET]], 1
+// SPIRV: define spir_func {{.*}} float {{.*}}test_scalar{{.*}}(double {{.*}} [[VALD:%.*]])
+// SPIRV-NOT: @llvm.dx.splitdouble
+// SPIRV: [[REG:%.*]] = load double, ptr [[VALD]].addr
+// SPIRV: call spir_func void {{.*}}asuint{{.*}}(double {{.*}} [[REG]], {{.*}})
+float test_scalar(double D) {
+  uint A, B;
+  asuint(D, A, B);
+  return A + B;
+}
+
+
+// CHECK: define {{.*}} <3 x float> {{.*}}test_vector{{.*}}(<3 x double> {{.*}} [[VALD:%.*]])
+// CHECK-COUNT-3: [[VALREG:%.*]] = extractelement <3 x double> [[VALD]], i64 [[VALIDX:[0-3]]]
+// CHECK-NEXT: [[VALRET:%hlsl.asuint.*]] = {{.*}} call { i32, i32 } @llvm.dx.splitdouble.i32(double [[VALREG]])
+// CHECK-NEXT: extractvalue { i32, i32 } [[VALRET]], 0
+// CHECK-NEXT: extractvalue { i32, i32 } [[VALRET]], 1
+// SPIRV: define spir_func {{.*}} <3 x float> {{.*}}test_vector{{.*}}(<3 x double> {{.*}} [[VALD:%.*]])
+// SPIRV-NOT: @llvm.dx.splitdouble
+// SPIRV: [[REG:%.*]] = load <3 x double>, ptr [[VALD]].addr
+// SPIRV: call spir_func void {{.*}}asuint{{.*}}(<3 x double> {{.*}} [[REG]], {{.*}})
+float3 test_vector(double3 D) {
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farzonl wrote:

Why are these test cases casting to float?

https://github.com/llvm/llvm-project/pull/109331