[CodeGen] fix mapping from fmod calls to frem instruction
Similar to D40044 and discussed in D40594.
llvm-svn: 319619
diff --git a/clang/lib/CodeGen/CGBuiltin.cpp b/clang/lib/CodeGen/CGBuiltin.cpp
index 962f5d8..6324520 100644
--- a/clang/lib/CodeGen/CGBuiltin.cpp
+++ b/clang/lib/CodeGen/CGBuiltin.cpp
@@ -854,12 +854,11 @@
Result.Val.getFloat()));
}
- // Math builtins have the same semantics as their math library twins.
- // There are LLVM math intrinsics corresponding to math library functions
- // except the intrinsic will never set errno while the math library might.
- // Thus, we can transform math library and builtin calls to their
- // semantically-equivalent LLVM intrinsic counterparts if the call is marked
- // 'const' (it is known to never set errno).
+ // There are LLVM math intrinsics/instructions corresponding to math library
+ // functions except the LLVM op will never set errno while the math library
+ // might. Also, math builtins have the same semantics as their math library
+ // twins. Thus, we can transform math library and builtin calls to their
+ // LLVM counterparts if the call is marked 'const' (known to never set errno).
if (FD->hasAttr<ConstAttr>()) {
switch (BuiltinID) {
case Builtin::BIceil:
@@ -942,6 +941,19 @@
case Builtin::BI__builtin_fminl:
return RValue::get(emitBinaryBuiltin(*this, E, Intrinsic::minnum));
+ // fmod() is a special-case. It maps to the frem instruction rather than an
+ // LLVM intrinsic.
+ case Builtin::BIfmod:
+ case Builtin::BIfmodf:
+ case Builtin::BIfmodl:
+ case Builtin::BI__builtin_fmod:
+ case Builtin::BI__builtin_fmodf:
+ case Builtin::BI__builtin_fmodl: {
+ Value *Arg1 = EmitScalarExpr(E->getArg(0));
+ Value *Arg2 = EmitScalarExpr(E->getArg(1));
+ return RValue::get(Builder.CreateFRem(Arg1, Arg2, "fmod"));
+ }
+
case Builtin::BIlog:
case Builtin::BIlogf:
case Builtin::BIlogl:
@@ -1067,14 +1079,6 @@
return RValue::get(Result);
}
- case Builtin::BI__builtin_fmod:
- case Builtin::BI__builtin_fmodf:
- case Builtin::BI__builtin_fmodl: {
- Value *Arg1 = EmitScalarExpr(E->getArg(0));
- Value *Arg2 = EmitScalarExpr(E->getArg(1));
- Value *Result = Builder.CreateFRem(Arg1, Arg2, "fmod");
- return RValue::get(Result);
- }
case Builtin::BI__builtin_conj:
case Builtin::BI__builtin_conjf:
case Builtin::BI__builtin_conjl: {