[X86] Implement _builtin_ia32_vfmaddss and _builtin_ia32_vfmaddsd with native IR using llvm.fma intrinsic.

This generates some extra zeroing currently, but we should be able to quickly address that with some isel patterns.

llvm-svn: 336417

1 files changed, 10 insertions, 0 deletions

diff --git a/clang/lib/CodeGen/CGBuiltin.cpp b/clang/lib/CodeGen/CGBuiltin.cpp
index 56cf6a99524..f2efca8cc9c 100644
--- a/clang/lib/CodeGen/CGBuiltin.cpp
+++ b/clang/lib/CodeGen/CGBuiltin.cpp
@@ -9134,6 +9134,16 @@ Value *CodeGenFunction::EmitX86BuiltinExpr(unsigned BuiltinID,
     Value *Res = Builder.CreateCall(FMA, {A, B, C} );
     return Builder.CreateInsertElement(Ops[0], Res, (uint64_t)0);
   }
+  case X86::BI__builtin_ia32_vfmaddss:
+  case X86::BI__builtin_ia32_vfmaddsd: {
+    Value *A = Builder.CreateExtractElement(Ops[0], (uint64_t)0);
+    Value *B = Builder.CreateExtractElement(Ops[1], (uint64_t)0);
+    Value *C = Builder.CreateExtractElement(Ops[2], (uint64_t)0);
+    Function *FMA = CGM.getIntrinsic(Intrinsic::fma, A->getType());
+    Value *Res = Builder.CreateCall(FMA, {A, B, C} );
+    Value *Zero = Constant::getNullValue(Ops[0]->getType());
+    return Builder.CreateInsertElement(Zero, Res, (uint64_t)0);
+  }
   case X86::BI__builtin_ia32_vfmaddps:
   case X86::BI__builtin_ia32_vfmaddpd:
   case X86::BI__builtin_ia32_vfmaddps256: