[DXIL] Add tan intrinsic part 2

[farzonl]

This change is an implementation of #87367's investigation on supporting IEEE math operations as intrinsics.
Which was discussed in this RFC:
https://discourse.llvm.org/t/rfc-all-the-math-intrinsics/78294

If you want an overarching view of how this will all connect see:
#90088

Changes:

• llvm/include/llvm/IR/Intrinsics.td - Create the tan intrinsic
• llvm/lib/Target/DirectX/DXIL.td - Map int_tan (the tan intrinsic) to the equivalent DXIL Op.

[llvmbot]

@llvm/pr-subscribers-backend-directx

@llvm/pr-subscribers-llvm-ir

Author: Farzon Lotfi (farzonl)

Changes

This change is an implementation of #87367's investigation on supporting IEEE math operations as intrinsics.
Which was discussed in this RFC:
https://discourse.llvm.org/t/rfc-all-the-math-intrinsics/78294

If you want an overarching view of how this will all connect see:
#90088

Changes:

• llvm/include/llvm/IR/Intrinsics.td - Create the tan intrinsic
• llvm/lib/Target/DirectX/DXIL.td - Map int_tan (the tan intrinsic) to the equivalent DXIL Op.

---

Full diff: https://github.com/llvm/llvm-project/pull/90277.diff

4 Files Affected:

• (modified) llvm/include/llvm/IR/Intrinsics.td (+1)
• (modified) llvm/lib/Target/DirectX/DXIL.td (+3)
• (added) llvm/test/CodeGen/DirectX/tan.ll (+20)
• (added) llvm/test/CodeGen/DirectX/tan_error.ll (+10)

diff --git a/llvm/include/llvm/IR/Intrinsics.td b/llvm/include/llvm/IR/Intrinsics.td
index a14e9dedef8c9e..bf0ca1687a34d4 100644
--- a/llvm/include/llvm/IR/Intrinsics.td
+++ b/llvm/include/llvm/IR/Intrinsics.td
@@ -1025,6 +1025,7 @@ let IntrProperties = [IntrNoMem, IntrSpeculatable, IntrWillReturn] in {
   def int_powi : DefaultAttrsIntrinsic<[llvm_anyfloat_ty], [LLVMMatchType<0>, llvm_anyint_ty]>;
   def int_sin  : DefaultAttrsIntrinsic<[llvm_anyfloat_ty], [LLVMMatchType<0>]>;
   def int_cos  : DefaultAttrsIntrinsic<[llvm_anyfloat_ty], [LLVMMatchType<0>]>;
+  def int_tan  : DefaultAttrsIntrinsic<[llvm_anyfloat_ty], [LLVMMatchType<0>]>;
   def int_pow  : DefaultAttrsIntrinsic<[llvm_anyfloat_ty],
                            [LLVMMatchType<0>, LLVMMatchType<0>]>;
   def int_log  : DefaultAttrsIntrinsic<[llvm_anyfloat_ty], [LLVMMatchType<0>]>;
diff --git a/llvm/lib/Target/DirectX/DXIL.td b/llvm/lib/Target/DirectX/DXIL.td
index cd388ed3e3191b..24a0c8524230c5 100644
--- a/llvm/lib/Target/DirectX/DXIL.td
+++ b/llvm/lib/Target/DirectX/DXIL.td
@@ -266,6 +266,9 @@ def Cos  : DXILOpMapping<12, unary, int_cos,
 def Sin  : DXILOpMapping<13, unary, int_sin,
                          "Returns sine(theta) for theta in radians.",
                          [llvm_halforfloat_ty, LLVMMatchType<0>]>;
+def Tan  : DXILOpMapping<14, unary, int_tan,
+                         "Returns tangent(theta) for theta in radians.",
+                         [llvm_halforfloat_ty, LLVMMatchType<0>]>;
 def Exp2 : DXILOpMapping<21, unary, int_exp2,
                          "Returns the base 2 exponential, or 2**x, of the specified value."
                          "exp2(x) = 2**x.",
diff --git a/llvm/test/CodeGen/DirectX/tan.ll b/llvm/test/CodeGen/DirectX/tan.ll
new file mode 100644
index 00000000000000..567ab02d40f918
--- /dev/null
+++ b/llvm/test/CodeGen/DirectX/tan.ll
@@ -0,0 +1,20 @@
+; RUN: opt -S -dxil-op-lower < %s | FileCheck %s
+
+; Make sure dxil operation function calls for tan are generated for float and half.
+
+define noundef float @tan_float(float noundef %a) #0 {
+entry:
+; CHECK:call float @dx.op.unary.f32(i32 14, float %{{.*}})
+  %elt.tan = call float @llvm.tan.f32(float %a)
+  ret float %elt.tan
+}
+
+define noundef half @tan_half(half noundef %a) #0 {
+entry:
+; CHECK:call half @dx.op.unary.f16(i32 14, half %{{.*}})
+  %elt.tan = call half @llvm.tan.f16(half %a)
+  ret half %elt.tan
+}
+
+declare half @llvm.tan.f16(half)
+declare float @llvm.tan.f32(float)
diff --git a/llvm/test/CodeGen/DirectX/tan_error.ll b/llvm/test/CodeGen/DirectX/tan_error.ll
new file mode 100644
index 00000000000000..c870c36f54925d
--- /dev/null
+++ b/llvm/test/CodeGen/DirectX/tan_error.ll
@@ -0,0 +1,10 @@
+; RUN: not opt -S -dxil-op-lower %s 2>&1 | FileCheck %s
+
+; DXIL operation tan does not support double overload type
+; CHECK: LLVM ERROR: Invalid Overload
+
+define noundef double @tan_double(double noundef %a) #0 {
+entry:
+  %1 = call double @llvm.tan.f64(double %a)
+  ret double %1
+}

[hekota]

LGTM!