diff --git a/lib/Target/X86/X86FastISel.cpp b/lib/Target/X86/X86FastISel.cpp index 2a44803f5a1..811887bdc61 100644 --- a/lib/Target/X86/X86FastISel.cpp +++ b/lib/Target/X86/X86FastISel.cpp @@ -30,6 +30,7 @@ #include "llvm/CodeGen/MachineRegisterInfo.h" #include "llvm/Support/CallSite.h" #include "llvm/Support/GetElementPtrTypeIterator.h" +#include "llvm/Target/TargetOptions.h" using namespace llvm; namespace { @@ -1115,6 +1116,11 @@ bool X86FastISel::X86SelectCall(Instruction *I) { CC != CallingConv::X86_FastCall) return false; + // On X86, -tailcallopt changes the fastcc ABI. FastISel doesn't + // handle this for now. + if (CC == CallingConv::Fast && PerformTailCallOpt) + return false; + // Let SDISel handle vararg functions. const PointerType *PT = cast(CS.getCalledValue()->getType()); const FunctionType *FTy = cast(PT->getElementType()); diff --git a/test/CodeGen/X86/fast-isel-tailcall.ll b/test/CodeGen/X86/fast-isel-tailcall.ll new file mode 100644 index 00000000000..6f4d2026814 --- /dev/null +++ b/test/CodeGen/X86/fast-isel-tailcall.ll @@ -0,0 +1,13 @@ +; RUN: llvm-as < %s | llc -fast-isel -tailcallopt -march=x86 | not grep add +; PR4154 + +; On x86, -tailcallopt changes the ABI so the caller shouldn't readjust +; the stack pointer after the call in this code. + +define i32 @stub(i8* %t0) nounwind { +entry: + %t1 = load i32* inttoptr (i32 139708680 to i32*) ; [#uses=1] + %t2 = bitcast i8* %t0 to i32 (i32)* ; [#uses=1] + %t3 = call fastcc i32 %t2(i32 %t1) ; [#uses=1] + ret i32 %t3 +}