[WinEH] Correctly handle inlined __finally blocks with captures

We should also teach the inliner to collapse framerecover of
frameaddress of the current frame down to an alloca, but that can happen
later.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235459 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Reid Kleckner 2015-04-22 00:07:52 +00:00
parent d62a1e966c
commit 8992ead662
2 changed files with 81 additions and 6 deletions

View File

@ -175,7 +175,11 @@ public:
: Materializer(HandlerFn, VarInfo),
SelectorIDType(Type::getInt32Ty(HandlerFn->getContext())),
Int8PtrType(Type::getInt8PtrTy(HandlerFn->getContext())),
LPadMap(LPadMap) {}
LPadMap(LPadMap) {
auto AI = HandlerFn->getArgumentList().begin();
++AI;
EstablisherFrame = AI;
}
CloningAction handleInstruction(ValueToValueMapTy &VMap,
const Instruction *Inst,
@ -210,6 +214,9 @@ protected:
Type *SelectorIDType;
Type *Int8PtrType;
LandingPadMap &LPadMap;
/// The value representing the parent frame pointer.
Value *EstablisherFrame;
};
class WinEHCatchDirector : public WinEHCloningDirectorBase {
@ -520,12 +527,24 @@ bool WinEHPrepare::prepareExceptionHandlers(
Intrinsic::getDeclaration(M, Intrinsic::frameescape);
Function *RecoverFrameFn =
Intrinsic::getDeclaration(M, Intrinsic::framerecover);
SmallVector<Value *, 8> AllocasToEscape;
// Scan the entry block for an existing call to llvm.frameescape. We need to
// keep escaping those objects.
for (Instruction &I : F.front()) {
auto *II = dyn_cast<IntrinsicInst>(&I);
if (II && II->getIntrinsicID() == Intrinsic::frameescape) {
auto Args = II->arg_operands();
AllocasToEscape.append(Args.begin(), Args.end());
II->eraseFromParent();
break;
}
}
// Finally, replace all of the temporary allocas for frame variables used in
// the outlined handlers with calls to llvm.framerecover.
BasicBlock::iterator II = Entry->getFirstInsertionPt();
Instruction *AllocaInsertPt = II;
SmallVector<Value *, 8> AllocasToEscape;
for (auto &VarInfoEntry : FrameVarInfo) {
Value *ParentVal = VarInfoEntry.first;
TinyPtrVector<AllocaInst *> &Allocas = VarInfoEntry.second;
@ -1051,6 +1070,11 @@ void LandingPadMap::remapEHValues(ValueToValueMapTy &VMap, Value *EHPtrValue,
VMap[Extract] = SelectorValue;
}
static bool isFrameAddressCall(const Value *V) {
return match(const_cast<Value *>(V),
m_Intrinsic<Intrinsic::frameaddress>(m_SpecificInt(0)));
}
CloningDirector::CloningAction WinEHCloningDirectorBase::handleInstruction(
ValueToValueMapTy &VMap, const Instruction *Inst, BasicBlock *NewBB) {
// If this is one of the boilerplate landing pad instructions, skip it.
@ -1083,6 +1107,13 @@ CloningDirector::CloningAction WinEHCloningDirectorBase::handleInstruction(
if (match(Inst, m_Intrinsic<Intrinsic::eh_typeid_for>()))
return handleTypeIdFor(VMap, Inst, NewBB);
// When outlining llvm.frameaddress(i32 0), remap that to the second argument,
// which is the FP of the parent.
if (isFrameAddressCall(Inst)) {
VMap[Inst] = EstablisherFrame;
return CloningDirector::SkipInstruction;
}
// Continue with the default cloning behavior.
return CloningDirector::CloneInstruction;
}
@ -1584,10 +1615,6 @@ static void createCleanupHandler(LandingPadActions &Actions,
<< Action->getStartBlock()->getName() << "\n");
}
static bool isFrameAddressCall(Value *V) {
return match(V, m_Intrinsic<Intrinsic::frameaddress>(m_SpecificInt(0)));
}
static CallSite matchOutlinedFinallyCall(BasicBlock *BB,
Instruction *MaybeCall) {
// Look for finally blocks that Clang has already outlined for us.

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@ -6,9 +6,18 @@
target datalayout = "e-m:w-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-pc-windows-msvc"
%struct._RTL_CRITICAL_SECTION = type { %struct._RTL_CRITICAL_SECTION_DEBUG*, i32, i32, i8*, i8*, i64 }
%struct._RTL_CRITICAL_SECTION_DEBUG = type { i16, i16, %struct._RTL_CRITICAL_SECTION*, %struct._LIST_ENTRY, i32, i32, i32, i16, i16 }
%struct._LIST_ENTRY = type { %struct._LIST_ENTRY*, %struct._LIST_ENTRY* }
declare i32 @puts(i8*)
declare void @may_crash()
declare i32 @__C_specific_handler(...)
declare i8* @llvm.framerecover(i8*, i8*, i32) #1
declare i8* @llvm.frameaddress(i32)
declare void @llvm.frameescape(...)
declare dllimport void @EnterCriticalSection(%struct._RTL_CRITICAL_SECTION*)
declare dllimport void @LeaveCriticalSection(%struct._RTL_CRITICAL_SECTION*)
define void @use_finally() {
entry:
@ -33,3 +42,42 @@ lpad: ; preds = %entry
; CHECK-NEXT: cleanup
; CHECK-NEXT: call i8* (...) @llvm.eh.actions(i32 0, void (i8*, i8*)* @use_finally.cleanup)
; CHECK-NEXT: indirectbr i8* %recover, []
; Function Attrs: nounwind uwtable
define i32 @call_may_crash_locked() {
entry:
%p = alloca %struct._RTL_CRITICAL_SECTION, align 8
call void (...) @llvm.frameescape(%struct._RTL_CRITICAL_SECTION* %p)
call void @EnterCriticalSection(%struct._RTL_CRITICAL_SECTION* %p)
invoke void @may_crash()
to label %invoke.cont unwind label %lpad
invoke.cont: ; preds = %entry
%tmp2 = call i8* @llvm.frameaddress(i32 0)
%tmp3 = call i8* @llvm.framerecover(i8* bitcast (i32 ()* @call_may_crash_locked to i8*), i8* %tmp2, i32 0) #2
%tmp6 = bitcast i8* %tmp3 to %struct._RTL_CRITICAL_SECTION*
call void @LeaveCriticalSection(%struct._RTL_CRITICAL_SECTION* %tmp6)
ret i32 42
lpad: ; preds = %entry
%tmp7 = landingpad { i8*, i32 } personality i8* bitcast (i32 (...)* @__C_specific_handler to i8*)
cleanup
%tmp8 = call i8* @llvm.frameaddress(i32 0)
%tmp9 = call i8* @llvm.framerecover(i8* bitcast (i32 ()* @call_may_crash_locked to i8*), i8* %tmp8, i32 0)
%tmp12 = bitcast i8* %tmp9 to %struct._RTL_CRITICAL_SECTION*
call void @LeaveCriticalSection(%struct._RTL_CRITICAL_SECTION* %tmp12)
resume { i8*, i32 } %tmp7
}
; CHECK-LABEL: define i32 @call_may_crash_locked()
; CHECK: invoke void @may_crash()
;
; CHECK: landingpad
; CHECK-NEXT: cleanup
; CHECK-NEXT: call i8* (...) @llvm.eh.actions(i32 0, void (i8*, i8*)* @call_may_crash_locked.cleanup)
; CHECK-NEXT: indirectbr i8* %recover, []
; CHECK-LABEL: define internal void @call_may_crash_locked.cleanup(i8*, i8*)
; CHECK: %tmp9 = call i8* @llvm.framerecover(i8* bitcast (i32 ()* @call_may_crash_locked to i8*), i8* %1, i32 0)
; CHECK: %tmp12 = bitcast i8* %tmp9 to %struct._RTL_CRITICAL_SECTION*
; CHECK: call void @LeaveCriticalSection(%struct._RTL_CRITICAL_SECTION* %tmp12)