ModulePass *createForwardControlFlowIntegrityPass();
} // End llvm namespace
-/// This initializer registers TargetMachine constructor, so the pass being
-/// initialized can use target dependent interfaces. Please do not move this
-/// macro to be together with INITIALIZE_PASS, which is a complete target
-/// independent initializer, and we don't want to make libScalarOpts depend
-/// on libCodeGen.
-#define INITIALIZE_TM_PASS(passName, arg, name, cfg, analysis) \
- static void* initialize##passName##PassOnce(PassRegistry &Registry) { \
+/// Target machine pass initializer for passes with dependencies. Use with
+/// INITIALIZE_TM_PASS_END.
+#define INITIALIZE_TM_PASS_BEGIN INITIALIZE_PASS_BEGIN
+
+/// Target machine pass initializer for passes with dependencies. Use with
+/// INITIALIZE_TM_PASS_BEGIN.
+#define INITIALIZE_TM_PASS_END(passName, arg, name, cfg, analysis) \
PassInfo *PI = new PassInfo(name, arg, & passName ::ID, \
PassInfo::NormalCtor_t(callDefaultCtor< passName >), cfg, analysis, \
PassInfo::TargetMachineCtor_t(callTargetMachineCtor< passName >)); \
CALL_ONCE_INITIALIZATION(initialize##passName##PassOnce) \
}
+/// This initializer registers TargetMachine constructor, so the pass being
+/// initialized can use target dependent interfaces. Please do not move this
+/// macro to be together with INITIALIZE_PASS, which is a complete target
+/// independent initializer, and we don't want to make libScalarOpts depend
+/// on libCodeGen.
+#define INITIALIZE_TM_PASS(passName, arg, name, cfg, analysis) \
+ INITIALIZE_TM_PASS_BEGIN(passName, arg, name, cfg, analysis) \
+ INITIALIZE_TM_PASS_END(passName, arg, name, cfg, analysis)
+
#endif
initializeBranchFolderPassPass(Registry);
initializeCodeGenPreparePass(Registry);
initializeDeadMachineInstructionElimPass(Registry);
+ initializeDwarfEHPreparePass(Registry);
initializeEarlyIfConverterPass(Registry);
- initializeExpandPostRAPass(Registry);
initializeExpandISelPseudosPass(Registry);
+ initializeExpandPostRAPass(Registry);
initializeFinalizeMachineBundlesPass(Registry);
initializeGCMachineCodeAnalysisPass(Registry);
initializeGCModuleInfoPass(Registry);
initializeLiveStacksPass(Registry);
initializeLiveVariablesPass(Registry);
initializeLocalStackSlotPassPass(Registry);
+ initializeLowerIntrinsicsPass(Registry);
initializeMachineBlockFrequencyInfoPass(Registry);
initializeMachineBlockPlacementPass(Registry);
initializeMachineBlockPlacementStatsPass(Registry);
- initializeMachineCopyPropagationPass(Registry);
- initializeMachineCombinerPass(Registry);
initializeMachineCSEPass(Registry);
+ initializeMachineCombinerPass(Registry);
+ initializeMachineCopyPropagationPass(Registry);
initializeMachineDominatorTreePass(Registry);
- initializeMachinePostDominatorTreePass(Registry);
+ initializeMachineFunctionPrinterPassPass(Registry);
initializeMachineLICMPass(Registry);
initializeMachineLoopInfoPass(Registry);
initializeMachineModuleInfoPass(Registry);
+ initializeMachinePostDominatorTreePass(Registry);
initializeMachineSchedulerPass(Registry);
initializeMachineSinkingPass(Registry);
initializeMachineVerifierPassPass(Registry);
initializeOptimizePHIsPass(Registry);
+ initializePEIPass(Registry);
initializePHIEliminationPass(Registry);
initializePeepholeOptimizerPass(Registry);
initializePostMachineSchedulerPass(Registry);
initializePostRASchedulerPass(Registry);
initializeProcessImplicitDefsPass(Registry);
- initializePEIPass(Registry);
initializeRegisterCoalescerPass(Registry);
initializeSlotIndexesPass(Registry);
- initializeStackProtectorPass(Registry);
initializeStackColoringPass(Registry);
+ initializeStackMapLivenessPass(Registry);
+ initializeStackProtectorPass(Registry);
initializeStackSlotColoringPass(Registry);
initializeTailDuplicatePassPass(Registry);
initializeTargetPassConfigPass(Registry);
initializeUnreachableMachineBlockElimPass(Registry);
initializeVirtRegMapPass(Registry);
initializeVirtRegRewriterPass(Registry);
- initializeLowerIntrinsicsPass(Registry);
- initializeMachineFunctionPrinterPassPass(Registry);
- initializeStackMapLivenessPass(Registry);
+ initializeWinEHPreparePass(Registry);
}
void LLVMInitializeCodeGen(LLVMPassRegistryRef R) {
//===----------------------------------------------------------------------===//
#include "llvm/CodeGen/Passes.h"
+#include "llvm/ADT/BitVector.h"
#include "llvm/ADT/Statistic.h"
+#include "llvm/Analysis/CFG.h"
+#include "llvm/Analysis/TargetTransformInfo.h"
+#include "llvm/IR/Dominators.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/Module.h"
#include "llvm/Pass.h"
#include "llvm/Target/TargetLowering.h"
#include "llvm/Target/TargetSubtargetInfo.h"
+#include "llvm/Transforms/Utils/Local.h"
using namespace llvm;
#define DEBUG_TYPE "dwarfehprepare"
// RewindFunction - _Unwind_Resume or the target equivalent.
Constant *RewindFunction;
+ DominatorTree *DT;
+ const TargetLowering *TLI;
+
bool InsertUnwindResumeCalls(Function &Fn);
Value *GetExceptionObject(ResumeInst *RI);
+ size_t
+ pruneUnreachableResumes(Function &Fn,
+ SmallVectorImpl<ResumeInst *> &Resumes,
+ SmallVectorImpl<LandingPadInst *> &CleanupLPads);
public:
static char ID; // Pass identification, replacement for typeid.
// INITIALIZE_TM_PASS requires a default constructor, but it isn't used in
// practice.
- DwarfEHPrepare() : FunctionPass(ID), TM(nullptr), RewindFunction(nullptr) {}
+ DwarfEHPrepare()
+ : FunctionPass(ID), TM(nullptr), RewindFunction(nullptr), DT(nullptr),
+ TLI(nullptr) {}
DwarfEHPrepare(const TargetMachine *TM)
- : FunctionPass(ID), TM(TM), RewindFunction(nullptr) {}
+ : FunctionPass(ID), TM(TM), RewindFunction(nullptr), DT(nullptr),
+ TLI(nullptr) {}
bool runOnFunction(Function &Fn) override;
return false;
}
+ void getAnalysisUsage(AnalysisUsage &AU) const override;
+
const char *getPassName() const override {
return "Exception handling preparation";
}
} // end anonymous namespace
char DwarfEHPrepare::ID = 0;
-INITIALIZE_TM_PASS(DwarfEHPrepare, "dwarfehprepare", "Prepare DWARF exceptions",
- false, false)
+INITIALIZE_TM_PASS_BEGIN(DwarfEHPrepare, "dwarfehprepare",
+ "Prepare DWARF exceptions", false, false)
+INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass)
+INITIALIZE_PASS_DEPENDENCY(TargetTransformInfoWrapperPass)
+INITIALIZE_TM_PASS_END(DwarfEHPrepare, "dwarfehprepare",
+ "Prepare DWARF exceptions", false, false)
FunctionPass *llvm::createDwarfEHPass(const TargetMachine *TM) {
return new DwarfEHPrepare(TM);
}
+void DwarfEHPrepare::getAnalysisUsage(AnalysisUsage &AU) const {
+ AU.addRequired<TargetTransformInfoWrapperPass>();
+ AU.addRequired<DominatorTreeWrapperPass>();
+}
+
/// GetExceptionObject - Return the exception object from the value passed into
/// the 'resume' instruction (typically an aggregate). Clean up any dead
/// instructions, including the 'resume' instruction.
return ExnObj;
}
+/// Replace resumes that are not reachable from a cleanup landing pad with
+/// unreachable and then simplify those blocks.
+size_t DwarfEHPrepare::pruneUnreachableResumes(
+ Function &Fn, SmallVectorImpl<ResumeInst *> &Resumes,
+ SmallVectorImpl<LandingPadInst *> &CleanupLPads) {
+ BitVector ResumeReachable(Resumes.size());
+ size_t ResumeIndex = 0;
+ for (auto *RI : Resumes) {
+ for (auto *LP : CleanupLPads) {
+ if (isPotentiallyReachable(LP, RI, DT)) {
+ ResumeReachable.set(ResumeIndex);
+ break;
+ }
+ }
+ ++ResumeIndex;
+ }
+
+ // If everything is reachable, there is no change.
+ if (ResumeReachable.all())
+ return Resumes.size();
+
+ const TargetTransformInfo &TTI =
+ getAnalysis<TargetTransformInfoWrapperPass>().getTTI(Fn);
+ LLVMContext &Ctx = Fn.getContext();
+
+ // Otherwise, insert unreachable instructions and call simplifycfg.
+ size_t ResumesLeft = 0;
+ for (size_t I = 0, E = Resumes.size(); I < E; ++I) {
+ ResumeInst *RI = Resumes[I];
+ if (ResumeReachable[I]) {
+ Resumes[ResumesLeft++] = RI;
+ } else {
+ BasicBlock *BB = RI->getParent();
+ new UnreachableInst(Ctx, RI);
+ RI->eraseFromParent();
+ SimplifyCFG(BB, TTI, 1, TLI->getDataLayout());
+ }
+ }
+ Resumes.resize(ResumesLeft);
+ return ResumesLeft;
+}
+
/// InsertUnwindResumeCalls - Convert the ResumeInsts that are still present
/// into calls to the appropriate _Unwind_Resume function.
bool DwarfEHPrepare::InsertUnwindResumeCalls(Function &Fn) {
SmallVector<ResumeInst*, 16> Resumes;
+ SmallVector<LandingPadInst*, 16> CleanupLPads;
for (BasicBlock &BB : Fn) {
if (auto *RI = dyn_cast<ResumeInst>(BB.getTerminator()))
Resumes.push_back(RI);
+ if (auto *LP = BB.getLandingPadInst())
+ if (LP->isCleanup())
+ CleanupLPads.push_back(LP);
}
if (Resumes.empty())
return false;
- // Find the rewind function if we didn't already.
- const TargetLowering *TLI = TM->getSubtargetImpl(Fn)->getTargetLowering();
LLVMContext &Ctx = Fn.getContext();
+
+ size_t ResumesLeft = pruneUnreachableResumes(Fn, Resumes, CleanupLPads);
+ if (ResumesLeft == 0)
+ return true; // We pruned them all.
+
+ // Find the rewind function if we didn't already.
if (!RewindFunction) {
FunctionType *FTy = FunctionType::get(Type::getVoidTy(Ctx),
Type::getInt8PtrTy(Ctx), false);
}
// Create the basic block where the _Unwind_Resume call will live.
- unsigned ResumesSize = Resumes.size();
-
- if (ResumesSize == 1) {
+ if (ResumesLeft == 1) {
// Instead of creating a new BB and PHI node, just append the call to
// _Unwind_Resume to the end of the single resume block.
ResumeInst *RI = Resumes.front();
}
BasicBlock *UnwindBB = BasicBlock::Create(Ctx, "unwind_resume", &Fn);
- PHINode *PN = PHINode::Create(Type::getInt8PtrTy(Ctx), ResumesSize,
+ PHINode *PN = PHINode::Create(Type::getInt8PtrTy(Ctx), ResumesLeft,
"exn.obj", UnwindBB);
// Extract the exception object from the ResumeInst and add it to the PHI node
bool DwarfEHPrepare::runOnFunction(Function &Fn) {
assert(TM && "DWARF EH preparation requires a target machine");
+ DT = &getAnalysis<DominatorTreeWrapperPass>().getDomTree();
+ TLI = TM->getSubtargetImpl(Fn)->getTargetLowering();
bool Changed = InsertUnwindResumeCalls(Fn);
+ DT = nullptr;
+ TLI = nullptr;
return Changed;
}
#include "llvm/ADT/MapVector.h"
#include "llvm/ADT/TinyPtrVector.h"
#include "llvm/Analysis/LibCallSemantics.h"
+#include "llvm/Analysis/TargetTransformInfo.h"
+#include "llvm/IR/Dominators.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/Instructions.h"
} // end anonymous namespace
char WinEHPrepare::ID = 0;
-INITIALIZE_TM_PASS(WinEHPrepare, "winehprepare", "Prepare Windows exceptions",
- false, false)
+INITIALIZE_TM_PASS_BEGIN(WinEHPrepare, "winehprepare",
+ "Prepare Windows exceptions", false, false)
+INITIALIZE_PASS_DEPENDENCY(DwarfEHPrepare)
+INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass)
+INITIALIZE_PASS_DEPENDENCY(TargetTransformInfoWrapperPass)
+INITIALIZE_TM_PASS_END(WinEHPrepare, "winehprepare",
+ "Prepare Windows exceptions", false, false)
FunctionPass *llvm::createWinEHPass(const TargetMachine *TM) {
return new WinEHPrepare(TM);
EHPersonality Pers = classifyEHPersonality(LPads.back()->getPersonalityFn());
// Delegate through to the DWARF pass if this is unrecognized.
- if (!isMSVCPersonality(Pers))
+ if (!isMSVCPersonality(Pers)) {
+ if (!DwarfPrepare->getResolver()) {
+ // Build an AnalysisResolver with the analyses needed by DwarfEHPrepare.
+ // It will take ownership of the AnalysisResolver.
+ assert(getResolver());
+ auto *AR = new AnalysisResolver(getResolver()->getPMDataManager());
+ AR->addAnalysisImplsPair(
+ &TargetTransformInfoWrapperPass::ID,
+ getResolver()->findImplPass(&TargetTransformInfoWrapperPass::ID));
+ AR->addAnalysisImplsPair(
+ &DominatorTreeWrapperPass::ID,
+ getResolver()->findImplPass(&DominatorTreeWrapperPass::ID));
+ DwarfPrepare->setResolver(AR);
+ }
+
return DwarfPrepare->runOnFunction(Fn);
+ }
// FIXME: This only returns true if the C++ EH handlers were outlined.
// When that code is complete, it should always return whatever
; CHECK-EL: bne $5
%exn.val = landingpad { i8*, i32 } personality i32 (...)* @__gxx_personality_v0
+ cleanup
catch i8* bitcast (i8** @_ZTId to i8*)
%exn = extractvalue { i8*, i32 } %exn.val, 0
%sel = extractvalue { i8*, i32 } %exn.val, 1
@int_typeinfo = global i8 0
declare void @might_throw()
+declare void @cleanup()
-define i32 @simple_catch() {
+define i32 @simple_cleanup_catch() {
invoke void @might_throw()
to label %cont unwind label %lpad
-; CHECK: define i32 @simple_catch()
+; CHECK-LABEL: define i32 @simple_cleanup_catch()
; CHECK: invoke void @might_throw()
cont:
lpad:
%ehvals = landingpad { i8*, i32 } personality i32 (...)* @__gxx_personality_v0
+ cleanup
catch i8* @int_typeinfo
%ehptr = extractvalue { i8*, i32 } %ehvals, 0
%ehsel = extractvalue { i8*, i32 } %ehvals, 1
+ call void @cleanup()
%int_sel = call i32 @llvm.eh.typeid.for(i8* @int_typeinfo)
%int_match = icmp eq i32 %ehsel, %int_sel
br i1 %int_match, label %catch_int, label %eh.resume
; CHECK: lpad:
; CHECK: landingpad { i8*, i32 } personality i32 (...)* @__gxx_personality_v0
+; CHECK: call void @cleanup()
; CHECK: call i32 @llvm.eh.typeid.for
; CHECK: br i1
; CHECK: ret i32 1
eh.resume:
- resume { i8*, i32 } %ehvals
+ %tmp_ehvals = insertvalue { i8*, i32 } undef, i8* %ehptr, 0
+ %new_ehvals = insertvalue { i8*, i32 } %tmp_ehvals, i32 %ehsel, 1
+ resume { i8*, i32 } %new_ehvals
; CHECK: eh.resume:
-; CHECK: call void @_Unwind_Resume(i8* %{{.*}})
+; CHECK-NEXT: call void @_Unwind_Resume(i8* %ehptr)
}
+
+define i32 @catch_no_resume() {
+ invoke void @might_throw()
+ to label %cont unwind label %lpad
+
+cont:
+ ret i32 0
+
+lpad:
+ %ehvals = landingpad { i8*, i32 } personality i32 (...)* @__gxx_personality_v0
+ catch i8* @int_typeinfo
+ %ehptr = extractvalue { i8*, i32 } %ehvals, 0
+ %ehsel = extractvalue { i8*, i32 } %ehvals, 1
+ %int_sel = call i32 @llvm.eh.typeid.for(i8* @int_typeinfo)
+ %int_match = icmp eq i32 %ehsel, %int_sel
+ br i1 %int_match, label %catch_int, label %eh.resume
+
+catch_int:
+ ret i32 1
+
+eh.resume:
+ %tmp_ehvals = insertvalue { i8*, i32 } undef, i8* %ehptr, 0
+ %new_ehvals = insertvalue { i8*, i32 } %tmp_ehvals, i32 %ehsel, 1
+ resume { i8*, i32 } %new_ehvals
+}
+
+; Check that we can prune the unreachable resume instruction.
+
+; CHECK-LABEL: define i32 @catch_no_resume() {
+; CHECK: invoke void @might_throw()
+; CHECK: ret i32 0
+; CHECK: lpad:
+; CHECK: landingpad { i8*, i32 } personality i32 (...)* @__gxx_personality_v0
+; CHECK-NOT: br i1
+; CHECK: ret i32 1
+; CHECK-NOT: call void @_Unwind_Resume
+; CHECK: {{^[}]}}
+
+
+define i32 @catch_cleanup_merge() {
+ invoke void @might_throw()
+ to label %inner_invoke unwind label %outer_lpad
+inner_invoke:
+ invoke void @might_throw()
+ to label %cont unwind label %inner_lpad
+cont:
+ ret i32 0
+
+outer_lpad:
+ %ehvals1 = landingpad { i8*, i32 } personality i32 (...)* @__gxx_personality_v0
+ catch i8* @int_typeinfo
+ br label %catch.dispatch
+
+inner_lpad:
+ %ehvals2 = landingpad { i8*, i32 } personality i32 (...)* @__gxx_personality_v0
+ cleanup
+ catch i8* @int_typeinfo
+ call void @cleanup()
+ br label %catch.dispatch
+
+catch.dispatch:
+ %ehvals = phi { i8*, i32 } [ %ehvals1, %outer_lpad ], [ %ehvals2, %inner_lpad ]
+ %ehptr = extractvalue { i8*, i32 } %ehvals, 0
+ %ehsel = extractvalue { i8*, i32 } %ehvals, 1
+ %int_sel = call i32 @llvm.eh.typeid.for(i8* @int_typeinfo)
+ %int_match = icmp eq i32 %ehsel, %int_sel
+ br i1 %int_match, label %catch_int, label %eh.resume
+
+catch_int:
+ ret i32 1
+
+eh.resume:
+ %tmp_ehvals = insertvalue { i8*, i32 } undef, i8* %ehptr, 0
+ %new_ehvals = insertvalue { i8*, i32 } %tmp_ehvals, i32 %ehsel, 1
+ resume { i8*, i32 } %new_ehvals
+}
+
+; We can't prune this merge because one landingpad is a cleanup pad.
+
+; CHECK-LABEL: define i32 @catch_cleanup_merge()
+; CHECK: invoke void @might_throw()
+; CHECK: invoke void @might_throw()
+; CHECK: ret i32 0
+;
+; CHECK: outer_lpad:
+; CHECK: landingpad { i8*, i32 } personality i32 (...)* @__gxx_personality_v0
+; CHECK: br label %catch.dispatch
+;
+; CHECK: inner_lpad:
+; CHECK: landingpad { i8*, i32 } personality i32 (...)* @__gxx_personality_v0
+; CHECK: call void @cleanup()
+; CHECK: br label %catch.dispatch
+;
+; CHECK: catch.dispatch:
+; CHECK: call i32 @llvm.eh.typeid.for
+; CHECK: br i1
+; CHECK: catch_int:
+; CHECK: ret i32 1
+; CHECK: eh.resume:
+; CHECK-NEXT: call void @_Unwind_Resume(i8* %ehptr)
+
declare i32 @__gxx_personality_v0(...)
declare i32 @llvm.eh.typeid.for(i8*)
lpad:
%0 = landingpad { i8*, i32 } personality i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*)
+ cleanup
catch i8* bitcast (i8** @_ZTIi to i8*)
br label %eh.resume
lpad:
%0 = landingpad { i8*, i32 } personality i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*)
+ cleanup
catch i8* bitcast (void ()* @filt0 to i8*)
catch i8* bitcast (void ()* @filt1 to i8*)
%sel = extractvalue { i8*, i32 } %0, 1
; CHECK: bl __cxa_end_catch
lpad:
%0 = landingpad { i8*, i32 } personality i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*)
+ cleanup
catch i8* bitcast (i8** @_ZTIi to i8*)
catch i8* bitcast (i8** @_ZTId to i8*)
%1 = extractvalue { i8*, i32 } %0, 0
; CHECK: .long [[PRE_G]]-[[START]]
; CHECK: .long [[POST_G]]-[[PRE_G]]
; CHECK: .long [[LANDING]]-[[START]]
-; CHECK: .byte 3
+; CHECK: .byte 5
; CHECK: .long [[POST_G]]-[[START]]
; CHECK: .long [[END]]-[[POST_G]]
; CHECK: .long 0
; CHECK: .byte 0
-; CHECK: .byte 1
; CHECK: .byte 0
+; CHECK: .byte 1
+; CHECK: .byte 125
; CHECK: .byte 2
; CHECK: .byte 125
; CHECK: .long _ZTIi