llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT--> @llvm/pr-subscribers-llvm-support Author: Akshat Oke (optimisan) <details> <summary>Changes</summary> Recycler uses reinterpret_cast to an internal structure of size 8. Invalid write occurs if Recycler is used for objects with sizes less than 8. --- Full diff: https://github.com/llvm/llvm-project/pull/121425.diff 3 Files Affected: - (modified) llvm/include/llvm/Support/Recycler.h (+2) - (modified) llvm/unittests/Support/CMakeLists.txt (+1) - (added) llvm/unittests/Support/RecyclerTest.cpp (+46) ``````````diff diff --git a/llvm/include/llvm/Support/Recycler.h b/llvm/include/llvm/Support/Recycler.h index bbd9ae321ae30c..8cc882ea5fa058 100644 --- a/llvm/include/llvm/Support/Recycler.h +++ b/llvm/include/llvm/Support/Recycler.h @@ -85,6 +85,8 @@ class Recycler { "Recycler allocation alignment is less than object align!"); static_assert(sizeof(SubClass) <= Size, "Recycler allocation size is less than object size!"); + static_assert(Size >= sizeof(FreeNode) && + "Recycler size must be atleast 8"); return FreeList ? reinterpret_cast<SubClass *>(pop_val()) : static_cast<SubClass *>(Allocator.Allocate(Size, Align)); } diff --git a/llvm/unittests/Support/CMakeLists.txt b/llvm/unittests/Support/CMakeLists.txt index d64f89847aa8e7..6de81658264420 100644 --- a/llvm/unittests/Support/CMakeLists.txt +++ b/llvm/unittests/Support/CMakeLists.txt @@ -69,6 +69,7 @@ add_llvm_unittest(SupportTests PerThreadBumpPtrAllocatorTest.cpp ProcessTest.cpp ProgramTest.cpp + RecyclerTest.cpp RegexTest.cpp ReverseIterationTest.cpp ReplaceFileTest.cpp diff --git a/llvm/unittests/Support/RecyclerTest.cpp b/llvm/unittests/Support/RecyclerTest.cpp new file mode 100644 index 00000000000000..8cd763c0b83f8a --- /dev/null +++ b/llvm/unittests/Support/RecyclerTest.cpp @@ -0,0 +1,46 @@ +//===--- unittest/Support/RecyclerTest.cpp --------------------------------===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// + +#include "llvm/Support/Recycler.h" +#include "llvm/Support/AllocatorBase.h" +#include "gtest/gtest.h" + +using namespace llvm; + +namespace { + +struct Object1 { + char Data[1]; +}; + +class DecoratedMallocAllocator : public MallocAllocator { +public: + int DeallocCount = 0; + + template <typename T> void Deallocate(T *Ptr) { + DeallocCount++; + MallocAllocator::Deallocate(Ptr); + } +}; + +TEST(RecyclerTest, RecycleAllocation) { + DecoratedMallocAllocator Allocator; + // Recycler needs size to be atleast 8 bytes. + Recycler<Object1, 8, 8> R; + Object1 *A1 = R.Allocate(Allocator); + Object1 *A2 = R.Allocate(Allocator); + R.Deallocate(Allocator, A2); + Object1 *A3 = R.Allocate(Allocator); + EXPECT_EQ(A2, A3); // reuse the deallocated object. + R.Deallocate(Allocator, A1); + R.Deallocate(Allocator, A3); + R.clear(Allocator); // Should deallocate A1 and A3. + EXPECT_EQ(Allocator.DeallocCount, 2); +} + +} // end anonymous namespace `````````` </details> https://github.com/llvm/llvm-project/pull/121425 _______________________________________________ llvm-branch-commits mailing list llvm-branch-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-branch-commits
