3 Commits

Author	SHA1	Message	Date
Sanjay Patel	1a17022bda	optimize the AVX2 (integer) version of vperm2 into a shuffle ... ...because this is what happens when an instruction set puts its underwear on after its pants. This is an extension of r232852, r233100, and 233110: http://llvm.org/viewvc/llvm-project?view=revision&revision=232852 http://llvm.org/viewvc/llvm-project?view=revision&revision=233100 http://llvm.org/viewvc/llvm-project?view=revision&revision=233110 llvm-svn: 233127	2015-03-24 22:39:29 +00:00
Sanjay Patel	c077161b46	[X86, AVX] instcombine vperm2 intrinsics with zero inputs into shuffles ... This is the IR optimizer follow-on patch for D8563: the x86 backend patch that converts this kind of shuffle back into a vperm2. This is also a continuation of the transform that started in D8486. In that patch, Andrea suggested that we could convert vperm2 intrinsics that use zero masks into a single shuffle. This is an implementation of that suggestion. Differential Revision: http://reviews.llvm.org/D8567 llvm-svn: 233110	2015-03-24 20:36:42 +00:00
Sanjay Patel	cf8a53f502	[X86, AVX] instcombine common cases of vperm2* intrinsics into shuffles ... vperm2* intrinsics are just shuffles. In a few special cases, they're not even shuffles. Optimizing intrinsics in InstCombine is better than handling this in the front-end for at least two reasons: 1. Optimizing custom-written SSE intrinsic code at -O0 makes vector coders really angry (and so I have regrets about some patches from last week). 2. Doing mask conversion logic in header files is hard to write and subsequently read. There are a couple of TODOs in this patch to complete this optimization. Differential Revision: http://reviews.llvm.org/D8486 llvm-svn: 232852	2015-03-20 21:47:56 +00:00