This is an enhancement to SeparateConstOffsetFromGEP. With this patch, we can
extract a constant offset from "s/zext and/or/xor A, B".
Added a new test @ext_or to verify this enhancement.
Refactoring the code, I also extracted some common logic to function
Distributable.
llvm-svn: 209670
Fixed a TODO in r207783.
Add the extracted constant offset using GEP instead of ugly
ptrtoint+add+inttoptr. Using GEP simplifies future optimizations and makes IR
easier to understand.
Updated all affected tests, and added a new test in split-gep.ll to cover a
corner case where emitting uglygep is necessary.
llvm-svn: 209537
This optimization merges the common part of a group of GEPs, so we can compute
each pointer address by adding a simple offset to the common part.
The optimization is currently only enabled for the NVPTX backend, where it has
a large payoff on some benchmarks.
Review: http://reviews.llvm.org/D3462
Patch by Jingyue Wu.
llvm-svn: 207783
