https://github.com/tbaederr created
https://github.com/llvm/llvm-project/pull/155276
This reverts commit 9642aadf7064192164d1687378d28d6bda1978c9.
Since elem() only works on primitive arrays anyway, we don't have to do the
isArrayRoot() check at all.
>From ad39593f874733149daf4a27f87e285ac9d2e6d2 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Timm=20B=C3=A4der?= <tbae...@redhat.com>
Date: Mon, 25 Aug 2025 15:12:38 +0200
Subject: [PATCH] Reapply "[clang][bytecode] Fix incorrect offset in elem()
(#155157)"
This reverts commit 9642aadf7064192164d1687378d28d6bda1978c9.
Since elem() only works on primitive arrays anyway, we don't have to do
the isArrayRoot() check at all.
---
clang/lib/AST/ByteCode/EvaluationResult.cpp | 4 ++--
clang/lib/AST/ByteCode/Pointer.h | 11 +++++------
clang/test/AST/ByteCode/invalid.cpp | 8 ++++++++
3 files changed, 15 insertions(+), 8 deletions(-)
diff --git a/clang/lib/AST/ByteCode/EvaluationResult.cpp
b/clang/lib/AST/ByteCode/EvaluationResult.cpp
index b11531f4296a2..5110e243d167c 100644
--- a/clang/lib/AST/ByteCode/EvaluationResult.cpp
+++ b/clang/lib/AST/ByteCode/EvaluationResult.cpp
@@ -178,8 +178,8 @@ bool EvaluationResult::checkFullyInitialized(InterpState &S,
static void collectBlocks(const Pointer &Ptr,
llvm::SetVector<const Block *> &Blocks) {
auto isUsefulPtr = [](const Pointer &P) -> bool {
- return P.isLive() && !P.isZero() && !P.isDummy() && P.isDereferencable() &&
- !P.isUnknownSizeArray() && !P.isOnePastEnd();
+ return P.isLive() && P.isBlockPointer() && !P.isZero() && !P.isDummy() &&
+ P.isDereferencable() && !P.isUnknownSizeArray() &&
!P.isOnePastEnd();
};
if (!isUsefulPtr(Ptr))
diff --git a/clang/lib/AST/ByteCode/Pointer.h b/clang/lib/AST/ByteCode/Pointer.h
index 66e85f93a124e..ac3d32a020c97 100644
--- a/clang/lib/AST/ByteCode/Pointer.h
+++ b/clang/lib/AST/ByteCode/Pointer.h
@@ -694,15 +694,14 @@ class Pointer {
assert(asBlockPointer().Pointee);
assert(isDereferencable());
assert(getFieldDesc()->isPrimitiveArray());
+ assert(I < getFieldDesc()->getNumElems());
unsigned ElemByteOffset = I * getFieldDesc()->getElemSize();
- if (isArrayRoot())
- return *reinterpret_cast<T *>(asBlockPointer().Pointee->rawData() +
- asBlockPointer().Base + sizeof(InitMapPtr)
+
- ElemByteOffset);
+ unsigned ReadOffset = BS.Base + sizeof(InitMapPtr) + ElemByteOffset;
+ assert(ReadOffset + sizeof(T) <=
+ BS.Pointee->getDescriptor()->getAllocSize());
- return *reinterpret_cast<T *>(asBlockPointer().Pointee->rawData() + Offset
+
- ElemByteOffset);
+ return *reinterpret_cast<T *>(BS.Pointee->rawData() + ReadOffset);
}
/// Whether this block can be read from at all. This is only true for
diff --git a/clang/test/AST/ByteCode/invalid.cpp
b/clang/test/AST/ByteCode/invalid.cpp
index 2a6c2d13e8467..affb40eada870 100644
--- a/clang/test/AST/ByteCode/invalid.cpp
+++ b/clang/test/AST/ByteCode/invalid.cpp
@@ -58,3 +58,11 @@ namespace Casts {
/// Just make sure this doesn't crash.
float PR9558 = reinterpret_cast<const float&>("asd");
}
+
+
+/// This used to crash in collectBlock().
+struct S {
+};
+S s;
+S *sp[2] = {&s, &s};
+S *&spp = sp[1];
_______________________________________________
cfe-commits mailing list
cfe-commits@lists.llvm.org
https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
