llvm/test/Transforms/LoopIdiom, branch stable

PR14904: Segmentation fault running pass 'Recognize loop idioms'

2013-01-10T23:32:01Z

The root cause is mistakenly taking for granted that "dyn_cast(a-Value)" return a non-NULL instruction. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172145 91177308-0d34-0410-b5e6-96231b3b80d8

Fix a mistaken commit that included some debugging code.

2013-01-07T13:41:55Z

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171734 91177308-0d34-0410-b5e6-96231b3b80d8

There was a switch fall-through in the parser for textual LLVM that caused

2013-01-07T13:32:38Z

bogus comparison operands to default to eq/oeq. Fix that, fix a couple of tests that accidentally passed and test for bogus comparison opeartors explicitly. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171733 91177308-0d34-0410-b5e6-96231b3b80d8

- Re-enable population count loop idiom recognization

2012-12-09T03:12:46Z

- fix a bug which cause sigfault. - add two testing cases which was causing crash git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169687 91177308-0d34-0410-b5e6-96231b3b80d8

Revert the patches adding a popcount loop idiom recognition pass.

2012-12-08T22:18:29Z

There are still bugs in this pass, as well as other issues that are being worked on, but the bugs are crashers that occur pretty easily in the wild. Test cases have been sent to the original commit's review thread. This reverts the commits: r169671: Fix a logic error. r169604: Move the popcnt tests to an X86 subdirectory. r168931: Initial commit adding the pass. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169683 91177308-0d34-0410-b5e6-96231b3b80d8

The test unconditionally assumes a particular cpu has a backend build in the target.

2012-12-07T15:57:45Z

Buildbots for some hosts may choose to build only their own backend in order to maximise testing-turnaround time. Move the test into a prefixed directory so lit's standard "backend specific" suppression can be done. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169604 91177308-0d34-0410-b5e6-96231b3b80d8

rdar://12100355 (part 1)

2012-11-29T19:38:54Z

This revision attempts to recognize following population-count pattern: while(a) { c++; ... ; a &= a - 1; ... }, where and could be used multiple times in the loop body. TODO: On X8664 and ARM, __buildin_ctpop() are not expanded to a efficent instruction sequence, which need to be improved in the following commits. Reviewed by Nadav, really appreciate! git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168931 91177308-0d34-0410-b5e6-96231b3b80d8

Add a testcase to loop-idiom to cover PR14241 when we start handling

2012-11-02T08:40:24Z

strided loops again. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167287 91177308-0d34-0410-b5e6-96231b3b80d8

Revert the switch of loop-idiom to use the new dependence analysis.

2012-11-02T08:33:25Z

The new analysis is not yet ready for prime time. It has a *critical* flawed assumption, and some troubling shortages of testing. Until it's been hammered into better shape, let's stick with the working code. This should be easy to revert itself when the analysis is ready. Fixes PR14241, a miscompile of any memcpy-able loop which uses a pointer as the induction mechanism. If you have been seeing miscompiles in this revision range, you really want to test with this backed out. The results of this miscompile are a bit subtle as they can lead to downstream passes concluding things are impossible which are in fact possible. Thanks to David Blaikie for the majority of the reduction of this miscompile. I'll be checking in the test case in a non-revert commit. Revesions reverted here: r167045: LoopIdiom: Fix a serious missed optimization: we only turned top-level loops into memmove. r166877: LoopIdiom: Add checks to avoid turning memmove into an infinite loop. r166875: LoopIdiom: Recognize memmove loops. r166874: LoopIdiom: Replace custom dependence analysis with DependenceAnalysis. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167286 91177308-0d34-0410-b5e6-96231b3b80d8

LCSSA: Add a workaround for another nasty SCEV cache invalidation issue.

2012-10-31T10:01:29Z

I'm not entirely happy with this solution, but I don't see a smarter way currently. Fixes PR14214. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167112 91177308-0d34-0410-b5e6-96231b3b80d8