mirror of
https://github.com/RPCS3/llvm-mirror.git
synced 2024-11-25 04:02:41 +01:00
ae65e281f3
to reflect the new license. We understand that people may be surprised that we're moving the header entirely to discuss the new license. We checked this carefully with the Foundation's lawyer and we believe this is the correct approach. Essentially, all code in the project is now made available by the LLVM project under our new license, so you will see that the license headers include that license only. Some of our contributors have contributed code under our old license, and accordingly, we have retained a copy of our old license notice in the top-level files in each project and repository. llvm-svn: 351636
95 lines
2.9 KiB
C++
95 lines
2.9 KiB
C++
//===- EscapeEnumerator.cpp -----------------------------------------------===//
|
|
//
|
|
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
|
|
// See https://llvm.org/LICENSE.txt for license information.
|
|
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
//
|
|
// Defines a helper class that enumerates all possible exits from a function,
|
|
// including exception handling.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#include "llvm/Transforms/Utils/EscapeEnumerator.h"
|
|
#include "llvm/Analysis/EHPersonalities.h"
|
|
#include "llvm/Transforms/Utils/Local.h"
|
|
#include "llvm/IR/CallSite.h"
|
|
#include "llvm/IR/Module.h"
|
|
using namespace llvm;
|
|
|
|
static Constant *getDefaultPersonalityFn(Module *M) {
|
|
LLVMContext &C = M->getContext();
|
|
Triple T(M->getTargetTriple());
|
|
EHPersonality Pers = getDefaultEHPersonality(T);
|
|
return M->getOrInsertFunction(getEHPersonalityName(Pers),
|
|
FunctionType::get(Type::getInt32Ty(C), true));
|
|
}
|
|
|
|
IRBuilder<> *EscapeEnumerator::Next() {
|
|
if (Done)
|
|
return nullptr;
|
|
|
|
// Find all 'return', 'resume', and 'unwind' instructions.
|
|
while (StateBB != StateE) {
|
|
BasicBlock *CurBB = &*StateBB++;
|
|
|
|
// Branches and invokes do not escape, only unwind, resume, and return
|
|
// do.
|
|
Instruction *TI = CurBB->getTerminator();
|
|
if (!isa<ReturnInst>(TI) && !isa<ResumeInst>(TI))
|
|
continue;
|
|
|
|
Builder.SetInsertPoint(TI);
|
|
return &Builder;
|
|
}
|
|
|
|
Done = true;
|
|
|
|
if (!HandleExceptions)
|
|
return nullptr;
|
|
|
|
if (F.doesNotThrow())
|
|
return nullptr;
|
|
|
|
// Find all 'call' instructions that may throw.
|
|
SmallVector<Instruction *, 16> Calls;
|
|
for (BasicBlock &BB : F)
|
|
for (Instruction &II : BB)
|
|
if (CallInst *CI = dyn_cast<CallInst>(&II))
|
|
if (!CI->doesNotThrow())
|
|
Calls.push_back(CI);
|
|
|
|
if (Calls.empty())
|
|
return nullptr;
|
|
|
|
// Create a cleanup block.
|
|
LLVMContext &C = F.getContext();
|
|
BasicBlock *CleanupBB = BasicBlock::Create(C, CleanupBBName, &F);
|
|
Type *ExnTy = StructType::get(Type::getInt8PtrTy(C), Type::getInt32Ty(C));
|
|
if (!F.hasPersonalityFn()) {
|
|
Constant *PersFn = getDefaultPersonalityFn(F.getParent());
|
|
F.setPersonalityFn(PersFn);
|
|
}
|
|
|
|
if (isScopedEHPersonality(classifyEHPersonality(F.getPersonalityFn()))) {
|
|
report_fatal_error("Scoped EH not supported");
|
|
}
|
|
|
|
LandingPadInst *LPad =
|
|
LandingPadInst::Create(ExnTy, 1, "cleanup.lpad", CleanupBB);
|
|
LPad->setCleanup(true);
|
|
ResumeInst *RI = ResumeInst::Create(LPad, CleanupBB);
|
|
|
|
// Transform the 'call' instructions into 'invoke's branching to the
|
|
// cleanup block. Go in reverse order to make prettier BB names.
|
|
SmallVector<Value *, 16> Args;
|
|
for (unsigned I = Calls.size(); I != 0;) {
|
|
CallInst *CI = cast<CallInst>(Calls[--I]);
|
|
changeToInvokeAndSplitBasicBlock(CI, CleanupBB);
|
|
}
|
|
|
|
Builder.SetInsertPoint(RI);
|
|
return &Builder;
|
|
}
|