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* Analysis: Remove implicit ilist iterator conversionsDuncan P. N. Exon Smith2015-10-101-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Remove implicit ilist iterator conversions from LLVMAnalysis. I came across something really scary in `llvm::isKnownNotFullPoison()` which relied on `Instruction::getNextNode()` being completely broken (not surprising, but scary nevertheless). This function is documented (and coded to) return `nullptr` when it gets to the sentinel, but with an `ilist_half_node` as a sentinel, the sentinel check looks into some other memory and we don't recognize we've hit the end. Rooting out these scary cases is the reason I'm removing the implicit conversions before doing anything else with `ilist`; I'm not at all surprised that clients rely on badness. I found another scary case -- this time, not relying on badness, just bad (but I guess getting lucky so far) -- in `ObjectSizeOffsetEvaluator::compute_()`. Here, we save out the insertion point, do some things, and then restore it. Previously, we let the iterator auto-convert to `Instruction*`, and then set it back using the `Instruction*` version: Instruction *PrevInsertPoint = Builder.GetInsertPoint(); /* Logic that may change insert point */ if (PrevInsertPoint) Builder.SetInsertPoint(PrevInsertPoint); The check for `PrevInsertPoint` doesn't protect correctly against bad accesses. If the insertion point has been set to the end of a basic block (i.e., `SetInsertPoint(SomeBB)`), then `GetInsertPoint()` returns an iterator pointing at the list sentinel. The version of `SetInsertPoint()` that's getting called will then call `PrevInsertPoint->getParent()`, which explodes horribly. The only reason this hasn't blown up is that it's fairly unlikely the builder is adding to the end of the block; usually, we're adding instructions somewhere before the terminator. llvm-svn: 249925
* [DivergenceAnalysis] Separated definition of class into header.Marcello Maggioni2015-09-211-54/+25
| | | | | | | | | | | | The definition of the DivergenceAnalysis pass was in a CPP file and wasn't accessible to users of the analysis to get it through "getAnalysis<>()". This patch extracts the definition into a separate header that can be used by users of the analysis to fetch the results. Patch by Volkan Keles (vkeles@apple.com) llvm-svn: 248186
* Rename inst_range() to instructions() for consistency. NFCNico Rieck2015-08-061-3/+3
| | | | llvm-svn: 244248
* Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC)Alexander Kornienko2015-06-231-1/+1
| | | | | | Apparently, the style needs to be agreed upon first. llvm-svn: 240390
* Fixed/added namespace ending comments using clang-tidy. NFCAlexander Kornienko2015-06-191-1/+1
| | | | | | | | | | | | | The patch is generated using this command: tools/clang/tools/extra/clang-tidy/tool/run-clang-tidy.py -fix \ -checks=-*,llvm-namespace-comment -header-filter='llvm/.*|clang/.*' \ llvm/lib/ Thanks to Eugene Kosov for the original patch! llvm-svn: 240137
* Divergence analysis for GPU programsJingyue Wu2015-04-101-0/+337
Summary: Some optimizations such as jump threading and loop unswitching can negatively affect performance when applied to divergent branches. The divergence analysis added in this patch conservatively estimates which branches in a GPU program can diverge. This information can then help LLVM to run certain optimizations selectively. Test Plan: test/Analysis/DivergenceAnalysis/NVPTX/diverge.ll Reviewers: resistor, hfinkel, eliben, meheff, jholewinski Subscribers: broune, bjarke.roune, madhur13490, tstellarAMD, dberlin, echristo, jholewinski, llvm-commits Differential Revision: http://reviews.llvm.org/D8576 llvm-svn: 234567
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