llvm-project/llvm/lib/Analysis/LibCallSemantics.cpp

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2.1 KiB
C++

//===- LibCallSemantics.cpp - Describe library semantics ------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements interfaces that can be used to describe language
// specific runtime library interfaces (e.g. libc, libm, etc) to LLVM
// optimizers.
//
//===----------------------------------------------------------------------===//
#include "llvm/Analysis/LibCallSemantics.h"
#include "llvm/ADT/StringSwitch.h"
#include "llvm/IR/Function.h"
using namespace llvm;
/// See if the given exception handling personality function is one that we
/// understand. If so, return a description of it; otherwise return Unknown.
EHPersonality llvm::classifyEHPersonality(const Value *Pers) {
const Function *F =
Pers ? dyn_cast<Function>(Pers->stripPointerCasts()) : nullptr;
if (!F)
return EHPersonality::Unknown;
return StringSwitch<EHPersonality>(F->getName())
.Case("__gnat_eh_personality", EHPersonality::GNU_Ada)
.Case("__gxx_personality_v0", EHPersonality::GNU_CXX)
.Case("__gcc_personality_v0", EHPersonality::GNU_C)
.Case("__objc_personality_v0", EHPersonality::GNU_ObjC)
.Case("_except_handler3", EHPersonality::MSVC_X86SEH)
.Case("_except_handler4", EHPersonality::MSVC_X86SEH)
.Case("__C_specific_handler", EHPersonality::MSVC_Win64SEH)
.Case("__CxxFrameHandler3", EHPersonality::MSVC_CXX)
.Case("ProcessCLRException", EHPersonality::CoreCLR)
.Default(EHPersonality::Unknown);
}
bool llvm::canSimplifyInvokeNoUnwind(const Function *F) {
EHPersonality Personality = classifyEHPersonality(F->getPersonalityFn());
// We can't simplify any invokes to nounwind functions if the personality
// function wants to catch asynch exceptions. The nounwind attribute only
// implies that the function does not throw synchronous exceptions.
return !isAsynchronousEHPersonality(Personality);
}