[llvm-profgen] Add branch/target validation (#188620) Add extra branch source and target validation checks for LBR samples. This is to check whether there are branch source samples that do not match a call/branch/ret instruction in the binary, and branch target samples that do not match a resolved Imm target address, or a function start address (in case of an indirect call). Example output: ``` # X86 warning: 0.01%(27/376876) of sampled target addresses do not match the binary. # AArch64 warning: 0.01%(63782/795824826) of branch samples do not match the binary. warning: 0.01%(70468/795824826) of branch targets do not match the binary. ``` Run time overhead: ``` Before: real 61m38.081s user 60m50.768s sys 0m42.931s After: real 62m33.176s user 61m47.650s sys 0m42.204s ```
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.