[DXIL] Add radians intrinsic (#110616)

makes progress on #99151

### Changes
- Added int_dx_radians intrinsic in IntrinsicsDirectX.td
- Added expansion for int_dx_radians in DXILIntrinsicExpansion.cpp`
- Added DXIL backend test case

### Related PRs
* [[clang][HLSL] Add radians intrinsic
#110802](#110802)
* [[SPIRV] Add radians intrinsic
#110800](#110800)

Author: adam-yang

llvm/include/llvm/IR/IntrinsicsDirectX.td

@@ -86,4 +86,5 @@ def int_dx_rsqrt  : DefaultAttrsIntrinsic<[llvm_anyfloat_ty], [LLVMMatchType<0>]
 def int_dx_wave_is_first_lane : DefaultAttrsIntrinsic<[llvm_i1_ty], [], [IntrConvergent]>;
 def int_dx_sign : DefaultAttrsIntrinsic<[LLVMScalarOrSameVectorWidth<0, llvm_i32_ty>], [llvm_any_ty], [IntrNoMem]>;
 def int_dx_step : DefaultAttrsIntrinsic<[LLVMMatchType<0>], [llvm_anyfloat_ty, LLVMMatchType<0>], [IntrNoMem]>;
+def int_dx_radians : DefaultAttrsIntrinsic<[llvm_anyfloat_ty], [LLVMMatchType<0>], [IntrNoMem]>;
 }

llvm/lib/Target/DirectX/DXILIntrinsicExpansion.cpp

@@ -64,6 +64,7 @@ static bool isIntrinsicExpansion(Function &F) {
   case Intrinsic::dx_udot:
   case Intrinsic::dx_sign:
   case Intrinsic::dx_step:
+  case Intrinsic::dx_radians:
     return true;
   }
   return false;
@@ -442,6 +443,14 @@ static Value *expandStepIntrinsic(CallInst *Orig) {
   return Builder.CreateSelect(Cond, Zero, One);
 }
 
+static Value *expandRadiansIntrinsic(CallInst *Orig) {
+  Value *X = Orig->getOperand(0);
+  Type *Ty = X->getType();
+  IRBuilder<> Builder(Orig);
+  Value *PiOver180 = ConstantFP::get(Ty, llvm::numbers::pi / 180.0);
+  return Builder.CreateFMul(X, PiOver180);
+}
+
 static Intrinsic::ID getMaxForClamp(Type *ElemTy,
                                     Intrinsic::ID ClampIntrinsic) {
   if (ClampIntrinsic == Intrinsic::dx_uclamp)
@@ -561,6 +570,9 @@ static bool expandIntrinsic(Function &F, CallInst *Orig) {
     break;
   case Intrinsic::dx_step:
     Result = expandStepIntrinsic(Orig);
+  case Intrinsic::dx_radians:
+    Result = expandRadiansIntrinsic(Orig);
+    break;
   }
   if (Result) {
     Orig->replaceAllUsesWith(Result);

llvm/test/CodeGen/DirectX/radians.ll

@@ -0,0 +1,79 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
+; RUN: opt -S -dxil-intrinsic-expansion -scalarizer -mtriple=dxil-pc-shadermodel6.3-library %s | FileCheck %s
+
+declare half @llvm.dx.radians.f16(half)
+declare float @llvm.dx.radians.f32(float)
+
+declare <4 x half> @llvm.dx.radians.v4f16(<4 x half>)
+declare <4 x float> @llvm.dx.radians.v4f32(<4 x float>)
+
+define noundef half @radians_half(half noundef %a) {
+; CHECK-LABEL: define noundef half @radians_half(
+; CHECK-SAME: half noundef [[A:%.*]]) {
+; CHECK-NEXT:  [[ENTRY:.*:]]
+; CHECK-NEXT:    [[TMP0:%.*]] = fmul half [[A]], 0xH2478
+; CHECK-NEXT:    ret half [[TMP0]]
+;
+entry:
+  %elt.radians = call half @llvm.dx.radians.f16(half %a)
+  ret half %elt.radians
+}
+
+define noundef float @radians_float(float noundef %a) {
+; CHECK-LABEL: define noundef float @radians_float(
+; CHECK-SAME: float noundef [[A:%.*]]) {
+; CHECK-NEXT:  [[ENTRY:.*:]]
+; CHECK-NEXT:    [[TMP0:%.*]] = fmul float [[A]], 0x3F91DF46A0000000
+; CHECK-NEXT:    ret float [[TMP0]]
+;
+entry:
+  %elt.radians = call float @llvm.dx.radians.f32(float %a)
+  ret float %elt.radians
+}
+
+define noundef <4 x half> @radians_half_vector(<4 x half> noundef %a) {
+; CHECK-LABEL: define noundef <4 x half> @radians_half_vector(
+; CHECK-SAME: <4 x half> noundef [[A:%.*]]) {
+; CHECK-NEXT:  [[ENTRY:.*:]]
+; CHECK: [[ee0:%.*]] = extractelement <4 x half> [[A]], i64 0
+; CHECK: [[ie0:%.*]] = fmul half [[ee0]], 0xH2478
+; CHECK: [[ee1:%.*]] = extractelement <4 x half> [[A]], i64 1
+; CHECK: [[ie1:%.*]] = fmul half [[ee1]], 0xH2478
+; CHECK: [[ee2:%.*]] = extractelement <4 x half> [[A]], i64 2
+; CHECK: [[ie2:%.*]] = fmul half [[ee2]], 0xH2478
+; CHECK: [[ee3:%.*]] = extractelement <4 x half> [[A]], i64 3
+; CHECK: [[ie3:%.*]] = fmul half [[ee3]], 0xH2478
+; CHECK: [[TMP0:%.*]] = insertelement <4 x half> poison, half [[ie0]], i64 0
+; CHECK: [[TMP1:%.*]] = insertelement <4 x half> %[[TMP0]], half [[ie1]], i64 1
+; CHECK: [[TMP2:%.*]] = insertelement <4 x half> %[[TMP1]], half [[ie2]], i64 2
+; CHECK: [[TMP3:%.*]] = insertelement <4 x half> %[[TMP2]], half [[ie3]], i64 3
+; CHECK: ret <4 x half> [[TMP3]]
+;
+entry:
+  %elt.radians = call <4 x half> @llvm.dx.radians.v4f16(<4 x half> %a)
+  ret <4 x half> %elt.radians
+}
+
+define noundef <4 x float> @radians_float_vector(<4 x float> noundef %a) {
+; CHECK-LABEL: define noundef <4 x float> @radians_float_vector(
+; CHECK-SAME: <4 x float> noundef [[A:%.*]]) {
+; CHECK-NEXT:  [[ENTRY:.*:]]
+; CHECK: [[ee0:%.*]] = extractelement <4 x float> [[A]], i64 0
+; CHECK: [[ie0:%.*]] = fmul float [[ee0]], 0x3F91DF46A0000000
+; CHECK: [[ee1:%.*]] = extractelement <4 x float> [[A]], i64 1
+; CHECK: [[ie1:%.*]] = fmul float [[ee1]], 0x3F91DF46A0000000
+; CHECK: [[ee2:%.*]] = extractelement <4 x float> [[A]], i64 2
+; CHECK: [[ie2:%.*]] = fmul float [[ee2]], 0x3F91DF46A0000000
+; CHECK: [[ee3:%.*]] = extractelement <4 x float> [[A]], i64 3
+; CHECK: [[ie3:%.*]] = fmul float [[ee3]], 0x3F91DF46A0000000
+; CHECK: [[TMP0:%.*]] = insertelement <4 x float> poison, float [[ie0]], i64 0
+; CHECK: [[TMP1:%.*]] = insertelement <4 x float> %[[TMP0]], float [[ie1]], i64 1
+; CHECK: [[TMP2:%.*]] = insertelement <4 x float> %[[TMP1]], float [[ie2]], i64 2
+; CHECK: [[TMP3:%.*]] = insertelement <4 x float> %[[TMP2]], float [[ie3]], i64 3
+; CHECK: ret <4 x float> [[TMP3]]
+;
+entry:
+  %elt.radians = call <4 x float> @llvm.dx.radians.v4f32(<4 x float> %a)
+  ret <4 x float> %elt.radians
+}
+