[llvm] r309651 - [StackColoring] Update AliasAnalysis information in stack coloring pass
Hiroshi 7 Inoue via llvm-commits
llvm-commits at lists.llvm.org
Mon Oct 2 09:20:03 PDT 2017
Hi Mikael,
Thank you for sharing your problem. I will investigate it.
Do you have this problem with the latest code base? I have updated my first
patch (r309651) in https://reviews.llvm.org/rL309849.
Regards,
Hiroshi
-----
Hiroshi Inoue <inouehrs at jp.ibm.com>
IBM Research - Tokyo
Mikael Holmén <mikael.holmen at ericsson.com> wrote on 2017/10/02 20:34:01:
> From: Mikael Holmén <mikael.holmen at ericsson.com>
> To: Hiroshi Inoue <inouehrs at jp.ibm.com>, <llvm-
> commits at lists.llvm.org>, "Hal Finkel" <hfinkel at anl.gov>, Matthias
> Braun <matze at braunis.de>
> Cc: Mattias Eriksson V <mattias.v.eriksson at ericsson.com>
> Date: 2017/10/02 20:35
> Subject: Re: [llvm] r309651 - [StackColoring] Update AliasAnalysis
> information in stack coloring pass
>
> Hi Hiroshi, Matthias and Hal,
>
> (CC my colleague Mattias)
>
> I think I've found a problem with this patch.
>
> Found it on my out-of-tree target, but I'll try to describe what's
> happening.
>
> The problem is during scheduling where we fail to identify a dependency
> between a store and a following load. The store _might_ store at the
> same address as the load loads from, but it doesn't always do it. It
> depends on earlier code flow.
>
> The store looks like:
>
> mv_a32_r16_rmod1 %a0_32, %r1; mem:ST2[%_tmp9] ST2[@g_290]
>
> I.e. it has two memops describing the two different memory locations it
> might store to (is this weird?). They memory locations are completely
> unrelated and describe the two locations the pointer %r1 can point to.
>
> Before this patch, when ScheduleDAGInstrs::buildSchedGraph called
>
> UnderlyingObjectsVector Objs;
> getUnderlyingObjectsForInstr(&MI, MFI, Objs, MF.getDataLayout());
>
> it got an empty Objs vector back since getUnderlyingObjectsForInstr
> found one non-identified object (%_tmp9) and then cleared the whole
vector.
>
> With this patch, I instead get a non-empty Objs, containing only @g_290
> and because of that we don't add a chain dependency towards the load
> following the store, and we get wrong code as a result.
>
> I know there is code in the method getUnderlyingObjectsForCodeGen that
> looks for non-identified objects and if found it clears the Objects
> arrays, but the way it's implemented it doesn't help!
>
> In my current case where there are two memops and the first one is
> non-identified, we still continue with the second memop afterwards and
> add that underlying object to the vector, and leave that to the
> schedgraph builder where we don't see any traces of any non-identified
> object, and we build a graph with missing dependencies
>
> I suppose this difference is not intended?
>
> Regards,
> Mikael
>
> On 08/01/2017 05:32 AM, Hiroshi Inoue via llvm-commits wrote:
> > Author: inouehrs
> > Date: Mon Jul 31 20:32:15 2017
> > New Revision: 309651
> >
> > URL: https://urldefense.proofpoint.com/v2/url?
>
u=http-3A__llvm.org_viewvc_llvm-2Dproject-3Frev-3D309651-26view-3Drev&d=DwICaQ&c=jf_iaSHvJObTbx-
> siA1ZOg&r=m0X4DAZw5Qh-99BsgZP4_s5n1wQ8Sz4aTCPvRS-
>
YkVI&m=mIxa9fsPE91JBDyRBM9jO3Gnmf1VjsdJcurWlZTiDmA&s=e3Q5lQrWHghbIG_b8_wJ0PPVh5IF218IDKqkTOkGGV0&e=
> > Log:
> > [StackColoring] Update AliasAnalysis information in stack coloring pass
> >
> > Stack coloring pass need to maintain AliasAnalysis information
> when merging stack slots of different types.
> > Actually, there is a FIXME comment in StackColoring.cpp
> >
> > // FIXME: In order to enable the use of TBAA when using AA in CodeGen,
> > // we'll also need to update the TBAA nodes in MMOs with values
> > // derived from the merged allocas.
> >
> > But, TBAA has been already enabled in CodeGen without fixing this pass.
> > The incorrect TBAA metadata results in recent failures in
> bootstrap test on ppc64le (PR33928) by allowing unsafe instruction
scheduling.
> > Although we observed the problem on ppc64le, this is a platform
> neutral issue.
> >
> > This patch makes the stack coloring pass maintains AliasAnalysis
> information when merging multiple stack slots.
> >
> >
> > Modified:
> > llvm/trunk/include/llvm/Analysis/ValueTracking.h
> > llvm/trunk/include/llvm/CodeGen/MachineFunction.h
> > llvm/trunk/include/llvm/CodeGen/MachineInstr.h
> > llvm/trunk/lib/Analysis/ValueTracking.cpp
> > llvm/trunk/lib/CodeGen/MachineFunction.cpp
> > llvm/trunk/lib/CodeGen/ScheduleDAGInstrs.cpp
> > llvm/trunk/lib/CodeGen/StackColoring.cpp
> >
> > Modified: llvm/trunk/include/llvm/Analysis/ValueTracking.h
> > URL: https://urldefense.proofpoint.com/v2/url?
>
u=http-3A__llvm.org_viewvc_llvm-2Dproject_llvm_trunk_include_llvm_Analysis_ValueTracking.h-3Frev-3D309651-26r1-3D309650-26r2-3D309651-26view-3Ddiff&d=DwICaQ&c=jf_iaSHvJObTbx-
> siA1ZOg&r=m0X4DAZw5Qh-99BsgZP4_s5n1wQ8Sz4aTCPvRS-
>
YkVI&m=mIxa9fsPE91JBDyRBM9jO3Gnmf1VjsdJcurWlZTiDmA&s=KsDAR0RUJBPSTneO3i2jMCIKtjKOSAi1260oq3nZfkA&e=
> >
>
==============================================================================
> > --- llvm/trunk/include/llvm/Analysis/ValueTracking.h (original)
> > +++ llvm/trunk/include/llvm/Analysis/ValueTracking.h Mon Jul 31
> 20:32:15 2017
> > @@ -312,6 +312,12 @@ template <typename T> class ArrayRef;
> > const DataLayout &DL, LoopInfo *LI =
nullptr,
> > unsigned MaxLookup = 6);
> >
> > + /// This is a wrapper around GetUnderlyingObjects and adds
> support for basic
> > + /// ptrtoint+arithmetic+inttoptr sequences.
> > + void getUnderlyingObjectsForCodeGen(const Value *V,
> > + SmallVectorImpl<Value *> &Objects,
> > + const DataLayout &DL);
> > +
> > /// Return true if the only users of this pointer are lifetime
markers.
> > bool onlyUsedByLifetimeMarkers(const Value *V);
> >
> >
> > Modified: llvm/trunk/include/llvm/CodeGen/MachineFunction.h
> > URL: https://urldefense.proofpoint.com/v2/url?
>
u=http-3A__llvm.org_viewvc_llvm-2Dproject_llvm_trunk_include_llvm_CodeGen_MachineFunction.h-3Frev-3D309651-26r1-3D309650-26r2-3D309651-26view-3Ddiff&d=DwICaQ&c=jf_iaSHvJObTbx-
> siA1ZOg&r=m0X4DAZw5Qh-99BsgZP4_s5n1wQ8Sz4aTCPvRS-
>
YkVI&m=mIxa9fsPE91JBDyRBM9jO3Gnmf1VjsdJcurWlZTiDmA&s=WJpDpSXhK9W0O2Y7ry9udwfGJezS0aC1GhsuQrPJ2a8&e=
> >
>
==============================================================================
> > --- llvm/trunk/include/llvm/CodeGen/MachineFunction.h (original)
> > +++ llvm/trunk/include/llvm/CodeGen/MachineFunction.h Mon Jul 31
> 20:32:15 2017
> > @@ -661,6 +661,12 @@ public:
> > MachineMemOperand *getMachineMemOperand(const MachineMemOperand
*MMO,
> > int64_t Offset, uint64_t
Size);
> >
> > + /// Allocate a new MachineMemOperand by copying an existing one,
> > + /// replacing only AliasAnalysis information.
> MachineMemOperands are owned
> > + /// by the MachineFunction and need not be explicitly deallocated.
> > + MachineMemOperand *getMachineMemOperand(const MachineMemOperand
*MMO,
> > + const AAMDNodes &AAInfo);
> > +
> > using OperandCapacity = ArrayRecycler<MachineOperand>::Capacity;
> >
> > /// Allocate an array of MachineOperands. This is only
> intended for use by
> >
> > Modified: llvm/trunk/include/llvm/CodeGen/MachineInstr.h
> > URL: https://urldefense.proofpoint.com/v2/url?
>
u=http-3A__llvm.org_viewvc_llvm-2Dproject_llvm_trunk_include_llvm_CodeGen_MachineInstr.h-3Frev-3D309651-26r1-3D309650-26r2-3D309651-26view-3Ddiff&d=DwICaQ&c=jf_iaSHvJObTbx-
> siA1ZOg&r=m0X4DAZw5Qh-99BsgZP4_s5n1wQ8Sz4aTCPvRS-
>
YkVI&m=mIxa9fsPE91JBDyRBM9jO3Gnmf1VjsdJcurWlZTiDmA&s=P1817BTam8xe_gWSipjZpR88qqNAdwIFFUXlfMpsB8I&e=
> >
>
==============================================================================
> > --- llvm/trunk/include/llvm/CodeGen/MachineInstr.h (original)
> > +++ llvm/trunk/include/llvm/CodeGen/MachineInstr.h Mon Jul 31 20:32:15
2017
> > @@ -379,6 +379,9 @@ public:
> > return NumMemRefs == 1;
> > }
> >
> > + /// Return the number of memory operands.
> > + unsigned getNumMemOperands() const { return NumMemRefs; }
> > +
> > /// API for querying MachineInstr properties. They are the
> same as MCInstrDesc
> > /// queries but they are bundle aware.
> >
> >
> > Modified: llvm/trunk/lib/Analysis/ValueTracking.cpp
> > URL: https://urldefense.proofpoint.com/v2/url?
>
u=http-3A__llvm.org_viewvc_llvm-2Dproject_llvm_trunk_lib_Analysis_ValueTracking.cpp-3Frev-3D309651-26r1-3D309650-26r2-3D309651-26view-3Ddiff&d=DwICaQ&c=jf_iaSHvJObTbx-
> siA1ZOg&r=m0X4DAZw5Qh-99BsgZP4_s5n1wQ8Sz4aTCPvRS-
>
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> >
>
==============================================================================
> > --- llvm/trunk/lib/Analysis/ValueTracking.cpp (original)
> > +++ llvm/trunk/lib/Analysis/ValueTracking.cpp Mon Jul 31 20:32:15 2017
> > @@ -3277,6 +3277,70 @@ void llvm::GetUnderlyingObjects(Value *V
> > } while (!Worklist.empty());
> > }
> >
> > +/// This is the function that does the work of looking through basic
> > +/// ptrtoint+arithmetic+inttoptr sequences.
> > +static const Value *getUnderlyingObjectFromInt(const Value *V) {
> > + do {
> > + if (const Operator *U = dyn_cast<Operator>(V)) {
> > + // If we find a ptrtoint, we can transfer control back to the
> > + // regular getUnderlyingObjectFromInt.
> > + if (U->getOpcode() == Instruction::PtrToInt)
> > + return U->getOperand(0);
> > + // If we find an add of a constant, a multiplied value, or
> a phi, it's
> > + // likely that the other operand will lead us to the base
> > + // object. We don't have to worry about the case where the
> > + // object address is somehow being computed by the multiply,
> > + // because our callers only care when the result is an
> > + // identifiable object.
> > + if (U->getOpcode() != Instruction::Add ||
> > + (!isa<ConstantInt>(U->getOperand(1)) &&
> > + Operator::getOpcode(U->getOperand(1)) != Instruction::Mul
&&
> > + !isa<PHINode>(U->getOperand(1))))
> > + return V;
> > + V = U->getOperand(0);
> > + } else {
> > + return V;
> > + }
> > + assert(V->getType()->isIntegerTy() && "Unexpected operand type!");
> > + } while (true);
> > +}
> > +
> > +/// This is a wrapper around GetUnderlyingObjects and adds
> support for basic
> > +/// ptrtoint+arithmetic+inttoptr sequences.
> > +void llvm::getUnderlyingObjectsForCodeGen(const Value *V,
> > + SmallVectorImpl<Value *> &Objects,
> > + const DataLayout &DL) {
> > + SmallPtrSet<const Value *, 16> Visited;
> > + SmallVector<const Value *, 4> Working(1, V);
> > + do {
> > + V = Working.pop_back_val();
> > +
> > + SmallVector<Value *, 4> Objs;
> > + GetUnderlyingObjects(const_cast<Value *>(V), Objs, DL);
> > +
> > + for (Value *V : Objs) {
> > + // If GetUnderlyingObjects fails to find an identifiable object,
> > + // getUnderlyingObjectsForCodeGen also fails for safety.
> > + if (!isIdentifiedObject(V)) {
> > + Objects.clear();
> > + return;
> > + }
> > +
> > + if (!Visited.insert(V).second)
> > + continue;
> > + if (Operator::getOpcode(V) == Instruction::IntToPtr) {
> > + const Value *O =
> > + getUnderlyingObjectFromInt(cast<User>(V)->getOperand(0));
> > + if (O->getType()->isPointerTy()) {
> > + Working.push_back(O);
> > + continue;
> > + }
> > + }
> > + Objects.push_back(const_cast<Value *>(V));
> > + }
> > + } while (!Working.empty());
> > +}
> > +
> > /// Return true if the only users of this pointer are lifetime
markers.
> > bool llvm::onlyUsedByLifetimeMarkers(const Value *V) {
> > for (const User *U : V->users()) {
> >
> > Modified: llvm/trunk/lib/CodeGen/MachineFunction.cpp
> > URL: https://urldefense.proofpoint.com/v2/url?
>
u=http-3A__llvm.org_viewvc_llvm-2Dproject_llvm_trunk_lib_CodeGen_MachineFunction.cpp-3Frev-3D309651-26r1-3D309650-26r2-3D309651-26view-3Ddiff&d=DwICaQ&c=jf_iaSHvJObTbx-
> siA1ZOg&r=m0X4DAZw5Qh-99BsgZP4_s5n1wQ8Sz4aTCPvRS-
>
YkVI&m=mIxa9fsPE91JBDyRBM9jO3Gnmf1VjsdJcurWlZTiDmA&s=allS8M0h249MGa_Gx6zUREWD57UANqNdgqwsYI7vnBc&e=
> >
>
==============================================================================
> > --- llvm/trunk/lib/CodeGen/MachineFunction.cpp (original)
> > +++ llvm/trunk/lib/CodeGen/MachineFunction.cpp Mon Jul 31 20:32:15 2017
> > @@ -330,6 +330,20 @@ MachineFunction::getMachineMemOperand(co
> > MMO->getOrdering(),
> MMO->getFailureOrdering());
> > }
> >
> > +MachineMemOperand *
> > +MachineFunction::getMachineMemOperand(const MachineMemOperand *MMO,
> > + const AAMDNodes &AAInfo) {
> > + MachinePointerInfo MPI = MMO->getValue() ?
> > + MachinePointerInfo(MMO->getValue(), MMO->getOffset()) :
> > + MachinePointerInfo(MMO->getPseudoValue(), MMO->getOffset
());
> > +
> > + return new (Allocator)
> > + MachineMemOperand(MPI, MMO->getFlags(), MMO->getSize(),
> > + MMO->getBaseAlignment(), AAInfo,
> > + MMO->getRanges(), MMO->getSyncScopeID
(),
> > + MMO->getOrdering(),
> MMO->getFailureOrdering());
> > +}
> > +
> > MachineInstr::mmo_iterator
> > MachineFunction::allocateMemRefsArray(unsigned long Num) {
> > return Allocator.Allocate<MachineMemOperand *>(Num);
> >
> > Modified: llvm/trunk/lib/CodeGen/ScheduleDAGInstrs.cpp
> > URL: https://urldefense.proofpoint.com/v2/url?
>
u=http-3A__llvm.org_viewvc_llvm-2Dproject_llvm_trunk_lib_CodeGen_ScheduleDAGInstrs.cpp-3Frev-3D309651-26r1-3D309650-26r2-3D309651-26view-3Ddiff&d=DwICaQ&c=jf_iaSHvJObTbx-
> siA1ZOg&r=m0X4DAZw5Qh-99BsgZP4_s5n1wQ8Sz4aTCPvRS-
> YkVI&m=mIxa9fsPE91JBDyRBM9jO3Gnmf1VjsdJcurWlZTiDmA&s=Ivq088QzLr4wNpGbN-
> k6QDpkRPbrJE6Z8WYbQgbAfXE&e=
> >
>
==============================================================================
> > --- llvm/trunk/lib/CodeGen/ScheduleDAGInstrs.cpp (original)
> > +++ llvm/trunk/lib/CodeGen/ScheduleDAGInstrs.cpp Mon Jul 31 20:32:15
2017
> > @@ -121,63 +121,6 @@ ScheduleDAGInstrs::ScheduleDAGInstrs(Mac
> > SchedModel.init(ST.getSchedModel(), &ST, TII);
> > }
> >
> > -/// This is the function that does the work of looking through basic
> > -/// ptrtoint+arithmetic+inttoptr sequences.
> > -static const Value *getUnderlyingObjectFromInt(const Value *V) {
> > - do {
> > - if (const Operator *U = dyn_cast<Operator>(V)) {
> > - // If we find a ptrtoint, we can transfer control back to the
> > - // regular getUnderlyingObjectFromInt.
> > - if (U->getOpcode() == Instruction::PtrToInt)
> > - return U->getOperand(0);
> > - // If we find an add of a constant, a multiplied value, or
> a phi, it's
> > - // likely that the other operand will lead us to the base
> > - // object. We don't have to worry about the case where the
> > - // object address is somehow being computed by the multiply,
> > - // because our callers only care when the result is an
> > - // identifiable object.
> > - if (U->getOpcode() != Instruction::Add ||
> > - (!isa<ConstantInt>(U->getOperand(1)) &&
> > - Operator::getOpcode(U->getOperand(1)) != Instruction::Mul
&&
> > - !isa<PHINode>(U->getOperand(1))))
> > - return V;
> > - V = U->getOperand(0);
> > - } else {
> > - return V;
> > - }
> > - assert(V->getType()->isIntegerTy() && "Unexpected operand type!");
> > - } while (true);
> > -}
> > -
> > -/// This is a wrapper around GetUnderlyingObjects and adds
> support for basic
> > -/// ptrtoint+arithmetic+inttoptr sequences.
> > -static void getUnderlyingObjects(const Value *V,
> > - SmallVectorImpl<Value *> &Objects,
> > - const DataLayout &DL) {
> > - SmallPtrSet<const Value *, 16> Visited;
> > - SmallVector<const Value *, 4> Working(1, V);
> > - do {
> > - V = Working.pop_back_val();
> > -
> > - SmallVector<Value *, 4> Objs;
> > - GetUnderlyingObjects(const_cast<Value *>(V), Objs, DL);
> > -
> > - for (Value *V : Objs) {
> > - if (!Visited.insert(V).second)
> > - continue;
> > - if (Operator::getOpcode(V) == Instruction::IntToPtr) {
> > - const Value *O =
> > - getUnderlyingObjectFromInt(cast<User>(V)->getOperand(0));
> > - if (O->getType()->isPointerTy()) {
> > - Working.push_back(O);
> > - continue;
> > - }
> > - }
> > - Objects.push_back(const_cast<Value *>(V));
> > - }
> > - } while (!Working.empty());
> > -}
> > -
> > /// If this machine instr has memory reference information and
> it can be tracked
> > /// to a normal reference to a known object, return the Value
> for that object.
> > static void getUnderlyingObjectsForInstr(const MachineInstr *MI,
> > @@ -208,12 +151,10 @@ static void getUnderlyingObjectsForInstr
> >
> Objects.push_back(UnderlyingObjectsVector::value_type(PSV, MayAlias));
> > } else if (const Value *V = MMO->getValue()) {
> > SmallVector<Value *, 4> Objs;
> > - getUnderlyingObjects(V, Objs, DL);
> > + getUnderlyingObjectsForCodeGen(V, Objs, DL);
> >
> > for (Value *V : Objs) {
> > - if (!isIdentifiedObject(V))
> > - return false;
> > -
> > + assert(isIdentifiedObject(V));
> > Objects.push_back(UnderlyingObjectsVector::value_type(V,
true));
> > }
> > } else
> >
> > Modified: llvm/trunk/lib/CodeGen/StackColoring.cpp
> > URL: https://urldefense.proofpoint.com/v2/url?
>
u=http-3A__llvm.org_viewvc_llvm-2Dproject_llvm_trunk_lib_CodeGen_StackColoring.cpp-3Frev-3D309651-26r1-3D309650-26r2-3D309651-26view-3Ddiff&d=DwICaQ&c=jf_iaSHvJObTbx-
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> >
>
==============================================================================
> > --- llvm/trunk/lib/CodeGen/StackColoring.cpp (original)
> > +++ llvm/trunk/lib/CodeGen/StackColoring.cpp Mon Jul 31 20:32:15 2017
> > @@ -37,6 +37,7 @@
> > #include "llvm/CodeGen/MachineRegisterInfo.h"
> > #include "llvm/CodeGen/Passes.h"
> > #include "llvm/CodeGen/PseudoSourceValue.h"
> > +#include "llvm/CodeGen/SelectionDAGNodes.h"
> > #include "llvm/CodeGen/SlotIndexes.h"
> > #include "llvm/CodeGen/StackProtector.h"
> > #include "llvm/CodeGen/WinEHFuncInfo.h"
> > @@ -889,6 +890,10 @@ void StackColoring::remapInstructions(De
> >
> > // Keep a list of *allocas* which need to be remapped.
> > DenseMap<const AllocaInst*, const AllocaInst*> Allocas;
> > +
> > + // Keep a list of allocas which has been affected by the remap.
> > + SmallPtrSet<const AllocaInst*, 32> MergedAllocas;
> > +
> > for (const std::pair<int, int> &SI : SlotRemap) {
> > const AllocaInst *From = MFI->getObjectAllocation(SI.first);
> > const AllocaInst *To = MFI->getObjectAllocation(SI.second);
> > @@ -908,6 +913,10 @@ void StackColoring::remapInstructions(De
> > Inst = Cast;
> > }
> >
> > + // We keep both slots to maintain AliasAnalysis metadata later.
> > + MergedAllocas.insert(From);
> > + MergedAllocas.insert(To);
> > +
> > // Allow the stack protector to adjust its value map to
> account for the
> > // upcoming replacement.
> > SP->adjustForColoring(From, To);
> > @@ -939,13 +948,6 @@ void StackColoring::remapInstructions(De
> >
> > // Update the MachineMemOperand to use the new alloca.
> > for (MachineMemOperand *MMO : I.memoperands()) {
> > - // FIXME: In order to enable the use of TBAA when using
> AA in CodeGen,
> > - // we'll also need to update the TBAA nodes in MMOs with
values
> > - // derived from the merged allocas. When doing this,
> we'll need to use
> > - // the same variant of GetUnderlyingObjects that is used by
the
> > - // instruction scheduler (that can look through
ptrtoint/inttoptr
> > - // pairs).
> > -
> > // We've replaced IR-level uses of the remapped allocas,so we
only
> > // need to replace direct uses here.
> > const AllocaInst *AI =
> dyn_cast_or_null<AllocaInst>(MMO->getValue());
> > @@ -997,6 +999,48 @@ void StackColoring::remapInstructions(De
> > MO.setIndex(ToSlot);
> > FixedInstr++;
> > }
> > +
> > + // We adjust AliasAnalysis information for merged stack slots.
> > + MachineSDNode::mmo_iterator MemOps =
> > + MF->allocateMemRefsArray(I.getNumMemOperands());
> > + unsigned MemOpIdx = 0;
> > + bool ReplaceMemOps = false;
> > + for (MachineMemOperand *MMO : I.memoperands()) {
> > + // If this memory location can be a slot remapped here,
> > + // we remove AA information.
> > + bool MayHaveConflictingAAMD = false;
> > + if (MMO->getAAInfo()) {
> > + if (const Value *MMOV = MMO->getValue()) {
> > + SmallVector<Value *, 4> Objs;
> > + getUnderlyingObjectsForCodeGen(MMOV, Objs,
> MF->getDataLayout());
> > +
> > + if (Objs.empty())
> > + MayHaveConflictingAAMD = true;
> > + else
> > + for (Value *V : Objs) {
> > + // If this memory location comes from a known stack
slot
> > + // that is not remapped, we continue checking.
> > + // Otherwise, we need to invalidate AA infomation.
> > + const AllocaInst *AI = dyn_cast_or_null<AllocaInst>
(V);
> > + if (AI && MergedAllocas.count(AI)) {
> > + MayHaveConflictingAAMD = true;
> > + break;
> > + }
> > + }
> > + }
> > + }
> > + if (MayHaveConflictingAAMD) {
> > + MemOps[MemOpIdx++] = MF->getMachineMemOperand(MMO, AAMDNodes
());
> > + ReplaceMemOps = true;
> > + }
> > + else
> > + MemOps[MemOpIdx++] = MMO;
> > + }
> > +
> > + // If any memory operand is updated, set memory references of
> > + // this instruction.
> > + if (ReplaceMemOps)
> > + I.setMemRefs(std::make_pair(MemOps, I.getNumMemOperands()));
> > }
> >
> > // Update the location of C++ catch objects for the MSVC
> personality routine.
> >
> >
> > _______________________________________________
> > llvm-commits mailing list
> > llvm-commits at lists.llvm.org
> > https://urldefense.proofpoint.com/v2/url?
>
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>
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