Skip to content

[StackSafetyAnalysis] Bail out if MemIntrinsic length is -1 #77837

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
Jan 11, 2024
Merged

[StackSafetyAnalysis] Bail out if MemIntrinsic length is -1 #77837

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
2 changes: 1 addition & 1 deletion llvm/lib/Analysis/StackSafetyAnalysis.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -331,7 +331,7 @@ ConstantRange StackSafetyLocalAnalysis::getMemIntrinsicAccessRange(
const SCEV *Expr =
SE.getTruncateOrZeroExtend(SE.getSCEV(MI->getLength()), CalculationTy);
ConstantRange Sizes = SE.getSignedRange(Expr);
if (Sizes.getUpper().isNegative() || isUnsafe(Sizes))
if (!Sizes.getUpper().isStrictlyPositive() || isUnsafe(Sizes))
return UnknownRange;
Sizes = Sizes.sextOrTrunc(PointerSize);
ConstantRange SizeRange(APInt::getZero(PointerSize), Sizes.getUpper() - 1);
Expand Down
34 changes: 34 additions & 0 deletions llvm/test/Analysis/StackSafetyAnalysis/memintrin.ll
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -98,6 +98,40 @@ entry:
ret void
}

define void @MemsetHugeUpper_m1(i1 %bool) {
; CHECK-LABEL: MemsetHugeUpper_m1 dso_preemptable{{$}}
; CHECK-NEXT: args uses:
; CHECK-NEXT: allocas uses:
; CHECK-NEXT: x[4]: full-set
entry:
%x = alloca i32, align 4
br i1 %bool, label %if.then, label %if.end

if.then:
call void @llvm.memset.p0.i64(ptr %x, i8 0, i64 -1, i1 false)
br label %if.end

if.end:
ret void
}

define void @MemsetHugeUpper_m2(i1 %bool) {
; CHECK-LABEL: MemsetHugeUpper_m2 dso_preemptable{{$}}
; CHECK-NEXT: args uses:
; CHECK-NEXT: allocas uses:
; CHECK-NEXT: x[4]: full-set
entry:
%x = alloca i32, align 4
br i1 %bool, label %if.then, label %if.end

if.then:
call void @llvm.memset.p0.i64(ptr %x, i8 0, i64 -2, i1 false)
br label %if.end

if.end:
ret void
}

define void @MemcpyInBounds() {
; CHECK-LABEL: MemcpyInBounds dso_preemptable{{$}}
; CHECK-NEXT: args uses:
Expand Down