implement part of PR6083: codegen support for isinf. Like isnan,
this is generating correct but suboptimal (extra extend to double)
code for the float case. Will investigate next.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@103166 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGBuiltin.cpp b/lib/CodeGen/CGBuiltin.cpp
index 95c41db..651539f 100644
--- a/lib/CodeGen/CGBuiltin.cpp
+++ b/lib/CodeGen/CGBuiltin.cpp
@@ -71,7 +71,7 @@
/// Utility to insert an atomic instruction based Instrinsic::ID and
// the expression node, where the return value is the result of the
// operation.
-static RValue EmitBinaryAtomicPost(CodeGenFunction& CGF,
+static RValue EmitBinaryAtomicPost(CodeGenFunction &CGF,
Intrinsic::ID Id, const CallExpr *E,
Instruction::BinaryOps Op) {
const llvm::Type *ResType[2];
@@ -88,6 +88,30 @@
return llvm::ConstantInt::get(llvm::Type::getInt32Ty(Context), Value);
}
+
+/// EmitFAbs - Emit a call to fabs/fabsf/fabsl, depending on the type of ValTy,
+/// which must be a scalar floating point type.
+static Value *EmitFAbs(CodeGenFunction &CGF, Value *V, QualType ValTy) {
+ const BuiltinType *ValTyP = ValTy->getAs<BuiltinType>();
+ assert(ValTyP && "isn't scalar fp type!");
+
+ StringRef FnName;
+ switch (ValTyP->getKind()) {
+ default: assert(0 && "Isn't a scalar fp type!");
+ case BuiltinType::Float: FnName = "fabsf"; break;
+ case BuiltinType::Double: FnName = "fabs"; break;
+ case BuiltinType::LongDouble: FnName = "fabsl"; break;
+ }
+
+ // The prototype is something that takes and returns whatever V's type is.
+ std::vector<const llvm::Type*> Args;
+ Args.push_back(V->getType());
+ llvm::FunctionType *FT = llvm::FunctionType::get(V->getType(), Args, false);
+ llvm::Value *Fn = CGF.CGM.CreateRuntimeFunction(FT, FnName);
+
+ return CGF.Builder.CreateCall(Fn, V, "abs");
+}
+
RValue CodeGenFunction::EmitBuiltinExpr(const FunctionDecl *FD,
unsigned BuiltinID, const CallExpr *E) {
// See if we can constant fold this builtin. If so, don't emit it at all.
@@ -328,6 +352,16 @@
V = Builder.CreateFCmpUNO(V, V, "cmp");
return RValue::get(Builder.CreateZExt(V, ConvertType(E->getType()), "tmp"));
}
+
+ case Builtin::BI__builtin_isinf: {
+ // isinf(x) --> fabs(x) == infinity
+ Value *V = EmitScalarExpr(E->getArg(0));
+ V = EmitFAbs(*this, V, E->getArg(0)->getType());
+
+ V = Builder.CreateFCmpOEQ(V, ConstantFP::getInfinity(V->getType()),"isinf");
+ return RValue::get(Builder.CreateZExt(V, ConvertType(E->getType()), "tmp"));
+ }
+
case Builtin::BIalloca:
case Builtin::BI__builtin_alloca: {
// FIXME: LLVM IR Should allow alloca with an i64 size!