Skip to content

[GlobalOpt] Look through non-PointerType constant expressions. #125205

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

Open
wants to merge 1 commit into
base: main
Choose a base branch
from
+14 −8
Open

[GlobalOpt] Look through non-PointerType constant expressions. #125205

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
15 changes: 12 additions & 3 deletions llvm/lib/Transforms/Utils/GlobalStatus.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -78,8 +78,14 @@ static bool analyzeGlobalAux(const Value *V, GlobalStatus &GS,
return true;
} else {
// Ignore dead constant users.
if (!isSafeToDestroyConstant(C))
return true;
if (!isSafeToDestroyConstant(C)) {
if (CE) {
if (VisitedUsers.insert(CE).second)
if (analyzeGlobalAux(CE, GS, VisitedUsers))
return true;
} else
return true;
}
}
} else if (const Instruction *I = dyn_cast<Instruction>(UR)) {
if (!GS.HasMultipleAccessingFunctions) {
Expand Down Expand Up @@ -166,9 +172,12 @@ static bool analyzeGlobalAux(const Value *V, GlobalStatus &GS,
if (MTI->getArgOperand(1) == V)
GS.IsLoaded = true;
} else if (const MemSetInst *MSI = dyn_cast<MemSetInst>(I)) {
assert(MSI->getArgOperand(0) == V && "Memset only takes one pointer!");
if (MSI->getArgOperand(0) != V || MSI->getArgOperand(1) == V)
return true;
if (MSI->isVolatile())
return true;
assert(MSI->getArgOperand(0) == V &&
"First argument must be the pointer!");
GS.StoredType = GlobalStatus::Stored;
} else if (const auto *CB = dyn_cast<CallBase>(I)) {
if (CB->getIntrinsicID() == Intrinsic::threadlocal_address) {
Expand Down
2 changes: 0 additions & 2 deletions llvm/test/Transforms/GlobalOpt/cleanup-pointer-root-users-ptrtoint-add-constexpr.ll
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -12,8 +12,6 @@ declare i32 @fn1()
define void @stores_single_use_gep_constexpr() {
; CHECK-LABEL: @stores_single_use_gep_constexpr(
; CHECK-NEXT: entry:
; CHECK-NEXT: store ptr @fn0, ptr @global.20ptr, align 8
; CHECK-NEXT: store ptr @fn1, ptr getelementptr inbounds ([[STRUCT_GLOBAL_20PTR:%.*]], ptr @global.20ptr, i64 0, i32 1), align 8
; CHECK-NEXT: ret void
;
entry:
Expand Down
5 changes: 2 additions & 3 deletions llvm/test/Transforms/GlobalOpt/read-with-constexpr-users.ll
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -5,15 +5,14 @@
@H = internal global [2 x i64 ] zeroinitializer

;.
; CHECK: @G = internal global [2 x i64] zeroinitializer
; CHECK: @G = internal constant [2 x i64] zeroinitializer
; CHECK: @H = internal global [2 x i64] zeroinitializer
;.
define i64 @G_used_by_gep_inttoptr_exprs() {
; CHECK-LABEL: define i64 @G_used_by_gep_inttoptr_exprs() local_unnamed_addr {
; CHECK-NEXT: [[L:%.*]] = load i64, ptr @G, align 8
; CHECK-NEXT: [[GEP:%.*]] = getelementptr i8, ptr inttoptr (i64 add (i64 ptrtoint (ptr getelementptr inbounds nuw (i8, ptr @G, i64 16) to i64), i64 8) to ptr), i64 1
; CHECK-NEXT: [[C:%.*]] = icmp eq ptr [[GEP]], @G
; CHECK-NEXT: [[SEL:%.*]] = select i1 [[C]], i64 [[L]], i64 9
; CHECK-NEXT: [[SEL:%.*]] = select i1 [[C]], i64 0, i64 9
; CHECK-NEXT: ret i64 [[SEL]]
;
%l = load i64, ptr @G, align 8
Expand Down