Lower __builtin_fabs* to @llvm.fabs.*

mingw64's headers implement fabs by calling __builtin_fabs, so using the
library call results in an infinite loop. If the backend legalizes
@llvm.fabs as a call to fabs later, things should work out, as the crt
provides a definition.

llvm-svn: 221206

1 files changed, 7 insertions, 0 deletions

diff --git a/clang/lib/CodeGen/CGBuiltin.cpp b/clang/lib/CodeGen/CGBuiltin.cpp
index 0972e28069d..aa11a906f40 100644
--- a/clang/lib/CodeGen/CGBuiltin.cpp
+++ b/clang/lib/CodeGen/CGBuiltin.cpp
@@ -245,6 +245,13 @@ RValue CodeGenFunction::EmitBuiltinExpr(const FunctionDecl *FD,
 
     return RValue::get(Result);
   }
+  case Builtin::BI__builtin_fabs:
+  case Builtin::BI__builtin_fabsf:
+  case Builtin::BI__builtin_fabsl: {
+    Value *Arg1 = EmitScalarExpr(E->getArg(0));
+    Value *Result = EmitFAbs(*this, Arg1);
+    return RValue::get(Result);
+  }
   case Builtin::BI__builtin_fmod:
   case Builtin::BI__builtin_fmodf:
   case Builtin::BI__builtin_fmodl: {