[MemoryBuiltins] Consider index type size when aggregating gep offsets (#132365) [MemoryBuiltins] Consider index type size when aggregating gep offsets Main goal here is to fix some bugs seen with LowerConstantIntrinsics pass and the lowering of llvm.objectsize. In ObjectSizeOffsetVisitor::computeImpl we are using an external analysis together with stripAndAccumulateConstantOffsets. The idea is to compute the Min/Max value of individual offsets within a GEP. The bug solved here is that when doing the Min/Max comparisons the external analysis wasn't considering the index type size (given by the data layout), it was simply using the type from the IR. Since a GEP is defined as sext/truncating indices we need to consider the index type size in the external analysis. This solves a regression (false ubsan warnings) seen after commit https://github.com/llvm/llvm-project/commit/02b8ee281947f6cb39c7eb3c4bbba59322e9015b (https://github.com/llvm/llvm-project/pull/117849).
Welcome to the LLVM project!
This repository contains the source code for LLVM, a toolkit for the construction of highly optimized compilers, optimizers, and run-time environments.
The LLVM project has multiple components. The core of the project is itself called “LLVM”. This contains all of the tools, libraries, and header files needed to process intermediate representations and convert them into object files. Tools include an assembler, disassembler, bitcode analyzer, and bitcode optimizer.
C-like languages use the Clang frontend. This component compiles C, C++, Objective-C, and Objective-C++ code into LLVM bitcode -- and from there into object files, using LLVM.
Other components include: the libc++ C++ standard library, the LLD linker, and more.
Consult the Getting Started with LLVM page for information on building and running LLVM.
For information on how to contribute to the LLVM project, please take a look at the Contributing to LLVM guide.
Join the LLVM Discourse forums, Discord chat, LLVM Office Hours or Regular sync-ups.
The LLVM project has adopted a code of conduct for participants to all modes of communication within the project.