Skip to content

[clang][bytecode] Fix an out-of-bounds access with ia32_pmul* #154750

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
Aug 21, 2025
Merged

[clang][bytecode] Fix an out-of-bounds access with ia32_pmul* #154750

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
17 changes: 11 additions & 6 deletions clang/lib/AST/ByteCode/InterpBuiltin.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -2683,9 +2683,10 @@ static bool interp__builtin_ia32_pmul(InterpState &S, CodePtr OpPC,
const auto *VT = Call->getArg(0)->getType()->castAs<VectorType>();
PrimType ElemT = *S.getContext().classify(VT->getElementType());
unsigned SourceLen = VT->getNumElements();
SmallVector<APValue, 4> ResultElements;
ResultElements.reserve(SourceLen / 2);

PrimType DstElemT = *S.getContext().classify(
Call->getType()->castAs<VectorType>()->getElementType());
unsigned DstElem = 0;
for (unsigned I = 0; I != SourceLen; I += 2) {
APSInt Elem1;
APSInt Elem2;
Expand All @@ -2699,16 +2700,19 @@ static bool interp__builtin_ia32_pmul(InterpState &S, CodePtr OpPC,
case clang::X86::BI__builtin_ia32_pmuludq128:
case clang::X86::BI__builtin_ia32_pmuludq256:
case clang::X86::BI__builtin_ia32_pmuludq512:
Result = APSInt(llvm::APIntOps::muluExtended(Elem1, Elem2), true);
Result = APSInt(llvm::APIntOps::muluExtended(Elem1, Elem2),
/*IsUnsigned=*/true);
break;
case clang::X86::BI__builtin_ia32_pmuldq128:
case clang::X86::BI__builtin_ia32_pmuldq256:
case clang::X86::BI__builtin_ia32_pmuldq512:
Result = APSInt(llvm::APIntOps::mulsExtended(Elem1, Elem2), false);
Result = APSInt(llvm::APIntOps::mulsExtended(Elem1, Elem2),
/*IsUnsigned=*/false);
break;
}
INT_TYPE_SWITCH_NO_BOOL(ElemT,
{ Dst.elem<T>(I) = static_cast<T>(Result); });
INT_TYPE_SWITCH_NO_BOOL(DstElemT,
{ Dst.elem<T>(DstElem) = static_cast<T>(Result); });
++DstElem;
}

Dst.initializeAllElements();
Expand Down Expand Up @@ -3204,6 +3208,7 @@ bool InterpretBuiltin(InterpState &S, CodePtr OpPC, const CallExpr *Call,
case clang::X86::BI__builtin_ia32_pmuldq512:
case clang::X86::BI__builtin_ia32_pmuludq128:
case clang::X86::BI__builtin_ia32_pmuludq256:
case clang::X86::BI__builtin_ia32_pmuludq512:
return interp__builtin_ia32_pmul(S, OpPC, Call, BuiltinID);
case Builtin::BI__builtin_elementwise_fma:
return interp__builtin_elementwise_fma(S, OpPC, Call);
Expand Down