llvm-project

c7274fce - [AllocToken] Introduce AllocToken instrumentation pass (#156838)

[AllocToken] Introduce AllocToken instrumentation pass (#156838) Introduce `AllocToken`, an instrumentation pass designed to provide tokens to memory allocators enabling various heap organization strategies, such as heap partitioning. Initially, the pass instruments functions marked with a new attribute `sanitize_alloc_token` by rewriting allocation calls to include a token ID, appended as a function argument with the default ABI. The design aims to provide a flexible framework for implementing different token generation schemes. It currently supports the following token modes: - TypeHash (default): token IDs based on a hash of the allocated type - Random: statically-assigned pseudo-random token IDs - Increment: incrementing token IDs per TU For the `TypeHash` mode introduce support for `!alloc_token` metadata: the metadata can be attached to allocation calls to provide richer semantic information to be consumed by the AllocToken pass. Optimization remarks can be enabled to show where no metadata was available. An alternative "fast ABI" is provided, where instead of passing the token ID as an argument (e.g., `__alloc_token_malloc(size, id)`), the token ID is directly encoded into the name of the called function (e.g., `__alloc_token_0_malloc(size)`). Where the maximum tokens is small, this offers more efficient instrumentation by avoiding the overhead of passing an additional argument at each allocation site. Link: https://discourse.llvm.org/t/rfc-a-framework-for-allocator-partitioning-hints/87434 [1] --- This change is part of the following series: 1. https://github.com/llvm/llvm-project/pull/160131 2. https://github.com/llvm/llvm-project/pull/156838 3. https://github.com/llvm/llvm-project/pull/162098 4. https://github.com/llvm/llvm-project/pull/162099 5. https://github.com/llvm/llvm-project/pull/156839 6. https://github.com/llvm/llvm-project/pull/156840 7. https://github.com/llvm/llvm-project/pull/156841 8. https://github.com/llvm/llvm-project/pull/156842