[WinEH] Update WinEHFuncInfo if StackColoring merges allocas

Windows EH keeping track of which frame index corresponds to a catchpad
in order to inform the runtime where the catch parameter should be
initialized.  LLVM's optimizations are able to prove that the memory
used by the catch parameter can be reused with another memory
optimization, changing it's frame index.

We need to keep WinEHFuncInfo up to date with respect to this or we will
miscompile/assert.

This fixes PR26069.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@257158 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
David Majnemer 2016-01-08 08:03:55 +00:00
parent 7203e500c0
commit 204e31b7ab
3 changed files with 64 additions and 3 deletions

View File

@ -43,6 +43,7 @@
#include "llvm/CodeGen/PseudoSourceValue.h"
#include "llvm/CodeGen/SlotIndexes.h"
#include "llvm/CodeGen/StackProtector.h"
#include "llvm/CodeGen/WinEHFuncInfo.h"
#include "llvm/IR/DebugInfo.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/Function.h"
@ -570,6 +571,12 @@ void StackColoring::remapInstructions(DenseMap<int, int> &SlotRemap) {
}
}
if (WinEHFuncInfo *EHInfo = MF->getWinEHFuncInfo())
for (WinEHTryBlockMapEntry &TBME : EHInfo->TryBlockMap)
for (WinEHHandlerType &H : TBME.HandlerArray)
if (SlotRemap.count(H.CatchObj.FrameIndex))
H.CatchObj.FrameIndex = SlotRemap[H.CatchObj.FrameIndex];
DEBUG(dbgs()<<"Fixed "<<FixedMemOp<<" machine memory operands.\n");
DEBUG(dbgs()<<"Fixed "<<FixedDbg<<" debug locations.\n");
DEBUG(dbgs()<<"Fixed "<<FixedInstr<<" machine instructions.\n");

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@ -144,10 +144,11 @@ static void addTryBlockMapEntry(WinEHFuncInfo &FuncInfo, int TryLow,
HT.TypeDescriptor = cast<GlobalVariable>(TypeInfo->stripPointerCasts());
HT.Adjectives = cast<ConstantInt>(CPI->getArgOperand(1))->getZExtValue();
HT.Handler = CPI->getParent();
if (isa<ConstantPointerNull>(CPI->getArgOperand(2)))
HT.CatchObj.Alloca = nullptr;
if (auto *AI =
dyn_cast<AllocaInst>(CPI->getArgOperand(2)->stripPointerCasts()))
HT.CatchObj.Alloca = AI;
else
HT.CatchObj.Alloca = cast<AllocaInst>(CPI->getArgOperand(2));
HT.CatchObj.Alloca = nullptr;
TBME.HandlerArray.push_back(HT);
}
FuncInfo.TryBlockMap.push_back(TBME);

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@ -0,0 +1,53 @@
; RUN: llc < %s | FileCheck %s
target datalayout = "e-m:x-p:32:32-i64:64-f80:32-n8:16:32-a:0:32-S32"
target triple = "x86_64-pc-windows-msvc"
declare void @throw()
declare i32 @__CxxFrameHandler3(...)
define void @test1() personality i32 (...)* @__CxxFrameHandler3 {
entry:
%alloca2 = alloca i8*, align 4
%alloca1 = alloca i8*, align 4
store volatile i8* null, i8** %alloca1
invoke void @throw()
to label %unreachable unwind label %catch.dispatch
; CHECK-LABEL: test1:
; CHECK: movq $0, -16(%rbp)
; CHECK: callq throw
catch.dispatch: ; preds = %entry
%cs = catchswitch within none [label %catch.pad] unwind to caller
catch.pad: ; preds = %catch.dispatch
%cp = catchpad within %cs [i8* null, i32 0, i8** %alloca1]
store volatile i8* null, i8** %alloca1
%bc1 = bitcast i8** %alloca1 to i8*
call void @llvm.lifetime.end(i64 4, i8* nonnull %bc1)
%bc2 = bitcast i8** %alloca2 to i8*
call void @llvm.lifetime.start(i64 4, i8* %bc2)
store volatile i8* null, i8** %alloca1
unreachable
; CHECK-LABEL: "?catch$2@?0?test1@4HA"
; CHECK: movq $0, -16(%rbp)
; CHECK: movq $0, -16(%rbp)
; CHECK: ud2
unreachable: ; preds = %entry
unreachable
}
; CHECK-LABEL: $cppxdata$test1:
; CHECK: .long 32 # CatchObjOffset
; Function Attrs: argmemonly nounwind
declare void @llvm.lifetime.start(i64, i8* nocapture) #0
; Function Attrs: argmemonly nounwind
declare void @llvm.lifetime.end(i64, i8* nocapture) #0
attributes #0 = { argmemonly nounwind }