e3cc8f3440
When a 128-bit load/store is aligned by 8, we incorrectly emit `load i16, ptr ..., align 2`
while the shadow memory address may not be aligned by 2.
This manifests as possibly-misaligned shadow memory load with `-mstrict-align`,
e.g. `clang --target=aarch64-linux -O2 -mstrict-align -fsanitize=address`
```
__attribute__((noinline)) void foo(unsigned long *ptr) {
ptr[0] = 3;
ptr[1] = 3;
}
// ldrh w8, [x9, x8] // the shadow memory load may not be aligned by 2
```
Infer the shadow memory alignment from the load/store alignment to set the
correct alignment. The generated code now uses two ldrb and one orr.
Fix https://github.com/llvm/llvm-project/issues/63258
Differential Revision: https://reviews.llvm.org/D152663
The LLVM Compiler Infrastructure
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.
Getting the Source Code and Building LLVM
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.
Getting in touch
Join the LLVM Discourse forums, Discord chat, or #llvm IRC channel on OFTC.
The LLVM project has adopted a code of conduct for participants to all modes of communication within the project.