Skip to content

[GlobalIsel] Add failure memory order to LegalityQuery (NFC) #162284

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 1 commit into from
Oct 9, 2025
+36 −26
Merged

[GlobalIsel] Add failure memory order to LegalityQuery (NFC) #162284

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
11 changes: 7 additions & 4 deletions llvm/include/llvm/CodeGen/GlobalISel/LegalizerInfo.h
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -115,14 +115,17 @@ struct LegalityQuery {
struct MemDesc {
LLT MemoryTy;
uint64_t AlignInBits;
AtomicOrdering Ordering;
AtomicOrdering Ordering; //< For cmpxchg this is the success ordering.
AtomicOrdering FailureOrdering; //< For cmpxchg, otherwise NotAtomic.

MemDesc() = default;
MemDesc(LLT MemoryTy, uint64_t AlignInBits, AtomicOrdering Ordering)
: MemoryTy(MemoryTy), AlignInBits(AlignInBits), Ordering(Ordering) {}
MemDesc(LLT MemoryTy, uint64_t AlignInBits, AtomicOrdering Ordering,
AtomicOrdering FailureOrdering)
Copy link
Contributor Author

@Maetveis Maetveis Oct 7, 2025 •
edited
Loading

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I was thinking of adding a default value of AtomicOrdering::NotAtomic to FailureOrdering, but I decided that being explicit might be better.
I don't feel strongly about this though. Without the default its possible this pr breaks downstream forks.

: MemoryTy(MemoryTy), AlignInBits(AlignInBits), Ordering(Ordering),
FailureOrdering(FailureOrdering) {}
MemDesc(const MachineMemOperand &MMO)
: MemDesc(MMO.getMemoryType(), MMO.getAlign().value() * 8,
MMO.getSuccessOrdering()) {}
MMO.getSuccessOrdering(), MMO.getFailureOrdering()) {}
};

/// Operations which require memory can use this to place requirements on the
Expand Down
2 changes: 1 addition & 1 deletion llvm/lib/CodeGen/GlobalISel/CombinerHelper.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1215,7 +1215,7 @@ bool CombinerHelper::isIndexedLoadStoreLegal(GLoadStore &LdSt) const {
LLT MemTy = LdSt.getMMO().getMemoryType();
SmallVector<LegalityQuery::MemDesc, 2> MemDescrs(
{{MemTy, MemTy.getSizeInBits().getKnownMinValue(),
AtomicOrdering::NotAtomic}});
AtomicOrdering::NotAtomic, AtomicOrdering::NotAtomic}});
unsigned IndexedOpc = getIndexedOpc(LdSt.getOpcode());
SmallVector<LLT> OpTys;
if (IndexedOpc == TargetOpcode::G_INDEXED_STORE)
Expand Down
3 changes: 2 additions & 1 deletion llvm/lib/CodeGen/GlobalISel/LoadStoreOpt.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -958,7 +958,8 @@ void LoadStoreOpt::initializeStoreMergeTargetInfo(unsigned AddrSpace) {
for (unsigned Size = 2; Size <= MaxStoreSizeToForm; Size *= 2) {
LLT Ty = LLT::scalar(Size);
SmallVector<LegalityQuery::MemDesc, 2> MemDescrs(
{{Ty, Ty.getSizeInBits(), AtomicOrdering::NotAtomic}});
{{Ty, Ty.getSizeInBits(), AtomicOrdering::NotAtomic,
AtomicOrdering::NotAtomic}});
SmallVector<LLT> StoreTys({Ty, PtrTy});
LegalityQuery Q(TargetOpcode::G_STORE, StoreTys, MemDescrs);
LegalizeActionStep ActionStep = LI.getAction(Q);
Expand Down
46 changes: 26 additions & 20 deletions llvm/unittests/CodeGen/GlobalISel/LegalizerInfoTest.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -480,18 +480,21 @@ TEST(LegalizerInfoTest, MMOAlignment) {

LegacyInfo.computeTables();

EXPECT_ACTION(Legal, 0, LLT(),
LegalityQuery(G_LOAD, {s32, p0},
LegalityQuery::MemDesc{
s32, 32, AtomicOrdering::NotAtomic}));
EXPECT_ACTION(Unsupported, 0, LLT(),
LegalityQuery(G_LOAD, {s32, p0},
LegalityQuery::MemDesc{
s32, 16, AtomicOrdering::NotAtomic }));
EXPECT_ACTION(Unsupported, 0, LLT(),
LegalityQuery(G_LOAD, {s32, p0},
LegalityQuery::MemDesc{
s32, 8, AtomicOrdering::NotAtomic}));
EXPECT_ACTION(
Legal, 0, LLT(),
LegalityQuery(G_LOAD, {s32, p0},
LegalityQuery::MemDesc{s32, 32, AtomicOrdering::NotAtomic,
AtomicOrdering::NotAtomic}));
EXPECT_ACTION(
Unsupported, 0, LLT(),
LegalityQuery(G_LOAD, {s32, p0},
LegalityQuery::MemDesc{s32, 16, AtomicOrdering::NotAtomic,
AtomicOrdering::NotAtomic}));
EXPECT_ACTION(
Unsupported, 0, LLT(),
LegalityQuery(G_LOAD, {s32, p0},
LegalityQuery::MemDesc{s32, 8, AtomicOrdering::NotAtomic,
AtomicOrdering::NotAtomic}));
}

// Test that the maximum supported alignment value isn't truncated
Expand All @@ -506,14 +509,17 @@ TEST(LegalizerInfoTest, MMOAlignment) {

LegacyInfo.computeTables();

EXPECT_ACTION(Legal, 0, LLT(),
LegalityQuery(G_LOAD, {s32, p0},
LegalityQuery::MemDesc{s32,
MaxAlignInBits, AtomicOrdering::NotAtomic}));
EXPECT_ACTION(Unsupported, 0, LLT(),
LegalityQuery(G_LOAD, {s32, p0},
LegalityQuery::MemDesc{
s32, 8, AtomicOrdering::NotAtomic }));
EXPECT_ACTION(
Legal, 0, LLT(),
LegalityQuery(G_LOAD, {s32, p0},
LegalityQuery::MemDesc{s32, MaxAlignInBits,
AtomicOrdering::NotAtomic,
AtomicOrdering::NotAtomic}));
EXPECT_ACTION(
Unsupported, 0, LLT(),
LegalityQuery(G_LOAD, {s32, p0},
LegalityQuery::MemDesc{s32, 8, AtomicOrdering::NotAtomic,
AtomicOrdering::NotAtomic}));
}
}

Expand Down
Loading