Commit Graph

3 Commits

Author SHA1 Message Date
Eric Christopher cee313d288 Revert "Temporarily Revert "Add basic loop fusion pass.""
The reversion apparently deleted the test/Transforms directory.

Will be re-reverting again.

llvm-svn: 358552
2019-04-17 04:52:47 +00:00
Eric Christopher a863435128 Temporarily Revert "Add basic loop fusion pass."
As it's causing some bot failures (and per request from kbarton).

This reverts commit r358543/ab70da07286e618016e78247e4a24fcb84077fda.

llvm-svn: 358546
2019-04-17 02:12:23 +00:00
Nikita Popov 36e03ac6ee [InstCombine] Fix negative GEP offset evaluation for 32-bit pointers
This fixes https://bugs.llvm.org/show_bug.cgi?id=39908.

The evaluateGEPOffsetExpression() function simplifies GEP offsets for
use in comparisons against zero, basically by converting X*Scale+Offset==0
to X+Offset/Scale==0 if Scale divides Offset. However, before this is done,
Offset is masked down to the pointer size. This results in incorrect
results for negative Offsets, because we basically end up dividing the
32-bit offset *zero* extended to 64-bit bits (rather than sign extended).

Fix this by explicitly sign extending the truncated value.

Differential Revision: https://reviews.llvm.org/D55449

llvm-svn: 348987
2018-12-12 23:19:03 +00:00