| commit | a96468b9adbef58bb0bf40b946275a530d378867 | [log] [tgz] |
|---|---|---|
| author | Sanjay Patel <spatel@rotateright.com> | Thu Jun 02 20:01:37 2016 +0000 |
| committer | Sanjay Patel <spatel@rotateright.com> | Thu Jun 02 20:01:37 2016 +0000 |
| tree | 68ad1a6ad64ee12b0461901c2cf7e99197f5c1c1 | |
| parent | 29d0ea4bc89c153bd530ab49d70bfac687f8f989 [diff] |
transform obscured FP sign bit ops into a fabs/fneg using TLI hook This is effectively a revert of: http://reviews.llvm.org/rL249702 - [InstCombine] transform masking off of an FP sign bit into a fabs() intrinsic call (PR24886) and: http://reviews.llvm.org/rL249701 - [ValueTracking] teach computeKnownBits that a fabs() clears sign bits and a reimplementation as a DAG combine for targets that have IEEE754-compliant fabs/fneg instructions. This is intended to resolve the objections raised on the dev list: http://lists.llvm.org/pipermail/llvm-dev/2016-April/098154.html and: https://llvm.org/bugs/show_bug.cgi?id=24886#c4 In the interest of patch minimalism, I've only partly enabled AArch64. PowerPC, MIPS, x86 and others can enable later. Differential Revision: http://reviews.llvm.org/D19391 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@271573 91177308-0d34-0410-b5e6-96231b3b80d8