[SelectionDAG] Clean up SCALAR_TO_VECTOR handling in SimplifyDemandedVectorElts (#157027) This patch reverts changes from commit 585e65d3307f5f0 (https://reviews.llvm.org/D104250), as it doesn't seem to be needed nowadays. The removed code was doing a recursive call to SimplifyDemandedVectorElts trying to simplify the vector %vec when finding things like (SCALAR_TO_VECTOR (EXTRACT_VECTOR_ELT %vec, 0)) I figure that (EXTRACT_VECTOR_ELT %vec, 0) would be simplified based on only demanding element zero regardless of being used in a SCALAR_TO_VECTOR operation or not. It had been different if the code tried to simplify the whole expression as %vec. That could also have motivate why to make element zero a special case. But it only simplified %vec without folding away the SCALAR_TO_VECTOR.
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.