[IR] Add `llvm.sincos` intrinsic (#109825)

This adds the `llvm.sincos` intrinsic, legalization, and lowering.

The `llvm.sincos` intrinsic takes a floating-point value and returns
both the sine and cosine (as a struct).

```
declare { float, float }          @llvm.sincos.f32(float  %Val)
declare { double, double }        @llvm.sincos.f64(double %Val)
declare { x86_fp80, x86_fp80 }    @llvm.sincos.f80(x86_fp80  %Val)
declare { fp128, fp128 }          @llvm.sincos.f128(fp128 %Val)
declare { ppc_fp128, ppc_fp128 }  @llvm.sincos.ppcf128(ppc_fp128  %Val)
declare { <4 x float>, <4 x float> } @llvm.sincos.v4f32(<4 x float>  %Val)
```

The lowering is built on top of the existing FSINCOS ISD node, with
additional type legalization to allow for f16, f128, and vector values.

1 files changed, 3 insertions, 2 deletions

diff --git a/llvm/lib/CodeGen/TargetLoweringBase.cpp b/llvm/lib/CodeGen/TargetLoweringBase.cpp
index cab0ed2..5bcde0e 100644
--- a/llvm/lib/CodeGen/TargetLoweringBase.cpp
+++ b/llvm/lib/CodeGen/TargetLoweringBase.cpp
@@ -773,8 +773,9 @@ void TargetLoweringBase::initActions() {
     setOperationAction({ISD::BITREVERSE, ISD::PARITY}, VT, Expand);
 
     // These library functions default to expand.
-    setOperationAction({ISD::FROUND, ISD::FPOWI, ISD::FLDEXP, ISD::FFREXP}, VT,
-                       Expand);
+    setOperationAction(
+        {ISD::FROUND, ISD::FPOWI, ISD::FLDEXP, ISD::FFREXP, ISD::FSINCOS}, VT,
+        Expand);
 
     // These operations default to expand for vector types.
     if (VT.isVector())