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* [ConstantRange] Rename a method and add more docSanjoy Das2016-02-221-5/+4
| | | | | | | | Rename makeNoWrapRegion to a more obvious makeGuaranteedNoWrapRegion, and add a comment about the counter-intuitive aspects of the function. This is to help prevent cases like PR26628. llvm-svn: 261532
* ADT: Remove == and != comparisons between ilist iterators and pointersDuncan P. N. Exon Smith2016-02-211-3/+3
| | | | | | | | | | | | | | I missed == and != when I removed implicit conversions between iterators and pointers in r252380 since they were defined outside ilist_iterator. Since they depend on getNodePtrUnchecked(), they indirectly rely on UB. This commit removes all uses of these operators. (I'll delete the operators themselves in a separate commit so that it can be easily reverted if necessary.) There should be NFC here. llvm-svn: 261498
* ScalerEvolution: Only erase temporary values if they actually have been addedTobias Grosser2016-02-211-5/+6
| | | | | | This addresses post-review comments from Sanjoy Das for r261485. llvm-svn: 261486
* ScalarEvolution: Do not keep temporary PHI values in ValueExprMapTobias Grosser2016-02-211-0/+5
| | | | | | | | | | Before this patch simplified SCEV expressions for PHI nodes were only returned the very first time getSCEV() was called, but later calls to getSCEV always returned the non-simplified value, which had "temporarily" been stored in the ValueExprMap, but was never removed and consequently blocked the caching of the simplified PHI expression. llvm-svn: 261485
* When MemoryDependenceAnalysis hits a CFG with many transparent blocks,Joerg Sonnenberger2016-02-201-6/+26
| | | | | | | | | | | | | | | | | | the algorithm easily degrades into quadratic memory and time complexity. The easiest example is a long chain of BBs that don't otherwise use a location. The caching will add an entry for every intermediate block and limiting the number of results doesn't help as no results are produced until a definition is found. Introduce a limit similar to the existing instructions-per-block limit. This limit counts the total number of blocks checked. If the limit is reached, entries are considered unknown. The initial value is 1000, which avoids regressions for normal sized functions while still limiting edge cases to reasnable memory consumption and execution time. Differential Revision: http://reviews.llvm.org/D16123 llvm-svn: 261430
* [LVI] Move ConstantRanges instead of copying.Benjamin Kramer2016-02-201-9/+8
| | | | | | | | No functional change intended. Copying small (<= 64 bits) APInts isn't expensive but bloats code by generating the slow path everywhere. Moving doesn't care about the size of the value. llvm-svn: 261426
* [PM/AA] Wire up CFLAA to the new pass manager fully, and port one of itsChandler Carruth2016-02-201-0/+1
| | | | | | | | | tests over to exercise this code. This uncovered a few missing bits here and there in the analysis, but nothing interesting. llvm-svn: 261404
* [PM/AA] Port alias analysis evaluator to the new pass manager, and useChandler Carruth2016-02-202-71/+66
| | | | | | | | | | | | | | | | it to actually test the new pass manager AA wiring. This patch was extracted from the (somewhat too large) D12357 and rebosed on top of the slightly different design of the new pass manager AA wiring that I just landed. With this we can start testing the AA in a thorough way with the new pass manager. Some minor cleanups to the code in the pass was necessitated here, but otherwise it is a very minimal change. Differential Revision: http://reviews.llvm.org/D17372 llvm-svn: 261403
* [SCEV] Don't spell `SCEV *` variables as `Scev`; NFCSanjoy Das2016-02-201-15/+14
| | | | | | | It reads odd since most other places name a `SCEV *` as `S`. Pure renaming change. llvm-svn: 261393
* [SCEV] Don't use std::make_pair; NFCSanjoy Das2016-02-201-15/+14
| | | | | | `{A, B}` reads cleaner than `std::make_pair(A, B)`. llvm-svn: 261392
* Remove uses of builtin comma operator.Richard Trieu2016-02-183-6/+12
| | | | | | Cleanup for upcoming Clang warning -Wcomma. No functionality change intended. llvm-svn: 261270
* [CaptureTracking] Support atomicrmw and cmpxchgPhilip Reames2016-02-181-0/+11
| | | | | | | | | | | | These atomic operations are conceptually both a load and store from the same location. As such, we can treat them as the most conservative of those two components which in practice, means we can treat them like stores. An cmpxchg or atomicrmw captures the values, but not the locations accessed. Note: We can probably be more aggressive about the comparison value in an cmpxhg since to have it be in memory, it must already be captured, but I figured it was better to avoid that for the moment. Note 2: It turns out that since we don't actually support cmpxchg of pointer type, writing a negative test is impossible. Differential Revision: http://reviews.llvm.org/D17400 llvm-svn: 261245
* [AliasSetTracker] Teach AliasSetTracker about MemSetInstHaicheng Wu2016-02-171-0/+41
| | | | | | | This change is to fix the problem discussed in http://lists.llvm.org/pipermail/llvm-dev/2016-February/095446.html. llvm-svn: 261052
* [LCG] Construct an actual call graph with call-edge SCCs nested insideChandler Carruth2016-02-171-388/+1181
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | reference-edge SCCs. This essentially builds a more normal call graph as a subgraph of the "reference graph" that was the old model. This allows both to exist and the different use cases to use the aspect which addresses their needs. Specifically, the pass manager and other *ordering* constrained logic can use the reference graph to achieve conservative order of visit, while analyses reasoning about attributes and other properties derived from reachability can reason about the direct call graph. Note that this isn't necessarily complete: it doesn't model edges to declarations or indirect calls. Those can be found by scanning the instructions of the function if desirable, and in fact every user currently does this in order to handle things like calls to instrinsics. If useful, we could consider caching this information in the call graph to save the instruction scans, but currently that doesn't seem to be important. An important realization for why the representation chosen here works is that the call graph is a formal subset of the reference graph and thus both can live within the same data structure. All SCCs of the call graph are necessarily contained within an SCC of the reference graph, etc. The design is to build 'RefSCC's to model SCCs of the reference graph, and then within them more literal SCCs for the call graph. The formation of actual call edge SCCs is not done lazily, unlike reference edge 'RefSCC's. Instead, once a reference SCC is formed, it directly builds the call SCCs within it and stores them in a post-order sequence. This is used to provide a consistent platform for mutation and update of the graph. The post-order also allows for very efficient updates in common cases by bounding the number of nodes (and thus edges) considered. There is considerable common code that I'm still looking for the best way to factor out between the various DFS implementations here. So far, my attempts have made the code harder to read and understand despite reducing the duplication, which seems a poor tradeoff. I've not given up on figuring out the right way to do this, but I wanted to wait until I at least had the system working and tested to continue attempting to factor it differently. This also requires introducing several new algorithms in order to handle all of the incremental update scenarios for the more complex structure involving two edge colorings. I've tried to comment the algorithms sufficiently to make it clear how this is expected to work, but they may still need more extensive documentation. I know that there are some changes which are not strictly necessarily coupled here. The process of developing this started out with a very focused set of changes for the new structure of the graph and algorithms, but subsequent changes to bring the APIs and code into consistent and understandable patterns also ended up touching on other aspects. There was no good way to separate these out without causing *massive* merge conflicts. Ultimately, to a large degree this is a rewrite of most of the core algorithms in the LCG class and so I don't think it really matters much. Many thanks to the careful review by Sanjoy Das! Differential Revision: http://reviews.llvm.org/D16802 llvm-svn: 261040
* Revert 260705, it appears to be causing pr26628Philip Reames2016-02-161-21/+0
| | | | | | The root issue appears to be a confusion around what makeNoWrapRegion actually does. It seems likely we need two versions of this function with slightly different semantics. llvm-svn: 260981
* [SCEVExpander] Make findExistingExpansion smarterJunmo Park2016-02-161-25/+35
| | | | | | | | | | | | | Summary: Extending findExistingExpansion can use existing value in ExprValueMap. This patch gives 0.3~0.5% performance improvements on benchmarks(test-suite, spec2000, spec2006, commercial benchmark) Reviewers: mzolotukhin, sanjoy, zzheng Differential Revision: http://reviews.llvm.org/D15559 llvm-svn: 260938
* [PM/AA] Actually wire the AAManager I built for the new pass managerChandler Carruth2016-02-131-0/+3
| | | | | | | | | | | | into the new pass manager and fix the latent bugs there. This lets everything live together nicely, but it isn't really useful yet. I never finished wiring the AA layer up for the new pass manager, and so subsequent patches will change this to do that wiring and get AA stuff more fully integrated into the new pass manager. Turns out this is necessary even to get functionattrs ported over. =] llvm-svn: 260836
* [ConstantFolding] Reduce APInt and APFloat copying.Benjamin Kramer2016-02-131-1/+1
| | | | llvm-svn: 260826
* Add convergent property to CodeMetrics.Justin Lebar2016-02-121-1/+4
| | | | | | | | | | | | Summary: No functional changes. Reviewers: jingyue, arsenm Subscribers: arsenm, llvm-commits Differential Revision: http://reviews.llvm.org/D17126 llvm-svn: 260728
* [LVI] Exploit nsw/nuw when computing constant rangesPhilip Reames2016-02-121-0/+21
| | | | | | | | | | As the title says. Modelled after similar code in SCEV. This is useful when analysing induction variables in loops which have been canonicalized by other passes. I wrote the tests as non-loops specifically to avoid the generality introduced in http://reviews.llvm.org/D17174. While that can handle many induction variables without *needing* to exploit nsw, there's no reason not to use it if we've already proven it. Differential Revision: http://reviews.llvm.org/D17177 llvm-svn: 260705
* [LVI] Improve select handling to use conditionPhilip Reames2016-02-121-0/+19
| | | | | | | | | | This patches teaches LVI to recognize clamp idioms (e.g. select(a > 5, a, 5) will always produce something greater than 5. The tests end up being somewhat simplistic because trying to exercise the case I actually care about (a loop with a range check on a clamped secondary induction variable) ends up tripping across a couple of other imprecisions in the analysis. Ah, the joys of LVI... Differential Revision: http://reviews.llvm.org/D16827 llvm-svn: 260627
* Make context-sensitive isDereferenceable queries in isSafeToLoadUnconditionallyArtur Pilipenko2016-02-111-2/+8
| | | | | | | | | | This is a part of the refactoring to unify isSafeToLoadUnconditionally and isDereferenceablePointer functions. In the subsequent change isSafeToSpeculativelyExecute will be modified to use isSafeToLoadUnconditionally instead of isDereferenceableAndAlignedPointer. Reviewed By: reames Differential Revision: http://reviews.llvm.org/D16227 llvm-svn: 260520
* [LVI] Handle constants defensivelyPhilip Reames2016-02-101-3/+7
| | | | | | | | | | There's nothing preventing callers of LVI from asking for lattice values representing a Constant. In fact, given that several callers are walking back through PHI nodes and trying to simplify predicates, such queries are actually quite common. This is mostly harmless today, but we start volatiling assertions if we add new calls to getBlockValue in otherwise reasonable places. Note that this change is not NFC. Specifically: 1) The result returned through getValueAt will now be more precise. In principle, this could trigger any latent infinite optimization loops in callers, but in practice, we're unlikely to see this. 2) The result returned through getBlockValueAt is potentially weakened for non-constants that were previously queried. With the old code, you had the possibility that a later query might bypass the cache and discover some information the original query did not. I can't find a scenario which actually causes this to happen, but it was in principle possible. On the other hand, this may end up reducing compile time when the same value is queried repeatedly. llvm-svn: 260439
* [MemoryBuiltins] Fix an issue with hasNoAliasAttrSanjoy Das2016-02-091-1/+1
| | | | | | | | | | | | | | | | | | | | | | | Summary: `hasNoAliasAttr` is buggy: it checks to see if the called function has a `noalias` attribute, which is incorrect since functions are not even allowed to have the `noalias` attribute. The comment on its only caller, `llvm::isNoAliasFn`, makes it pretty clear that the intention to do the `noalias` check on the return value, and not the callee. Unfortunately I couldn't find a way to test this upstream -- fixing this does not change the observable behavior of any of the passes that use this. This is not very surprising, since `noalias` does not tell anything about the contents of the allocated memory (so, e.g., you still cannot fold loads). I'll be happy to be proven wrong though. Reviewers: chandlerc, reames Subscribers: mcrosier, llvm-commits Differential Revision: http://reviews.llvm.org/D17037 llvm-svn: 260298
* [GMR/OperandBundles] Teach getModRefBehavior about operand bundlesSanjoy Das2016-02-091-7/+8
| | | | | | | | | In general, memory restrictions on a called function (e.g. readnone) cannot be transferred to a CallSite that has operand bundles. It is possible to make this inference smarter, but lets fix the behavior to be correct first. llvm-svn: 260193
* Add an "addUsedAAAnalyses" helper functionSanjoy Das2016-02-091-0/+11
| | | | | | | | | | | | | | | | | | | Summary: Passes that call `getAnalysisIfAvailable<T>` also need to call `addUsedIfAvailable<T>` in `getAnalysisUsage` to indicate to the legacy pass manager that it uses `T`. This contract was being violated by passes that used `createLegacyPMAAResults`. This change fixes this by exposing a helper in AliasAnalysis.h, `addUsedAAAnalyses`, that is complementary to createLegacyPMAAResults and does the right thing when called from `getAnalysisUsage`. Reviewers: chandlerc Subscribers: mcrosier, llvm-commits Differential Revision: http://reviews.llvm.org/D17010 llvm-svn: 260183
* Remove SCEVAAWrapperPass from createLegacyPMAAResults; NFCSanjoy Das2016-02-091-2/+0
| | | | | | | | | | | | | | | Summary: createLegacyPMAAResults is only called by CGSCC and Module passes, so the call to getAnalysisIfAvailable<SCEVAAWrapperPass>() never succeeds (SCEVAAWrapperPass is a function pass). Reviewers: chandlerc Subscribers: mcrosier, llvm-commits Differential Revision: http://reviews.llvm.org/D17009 llvm-svn: 260182
* This patch is to fix PR26529 caused by r259736.Wei Mi2016-02-091-4/+3
| | | | | | | | | | | | | | | | IndVarSimplify assumes scAddRecExpr to be expanded in literal form instead of canonical form by calling disableCanonicalMode after it creates SCEVExpander. When CanonicalMode is disabled, SCEVExpander::expand should always return PHI node for scAddRecExpr. r259736 broke the assumption. The fix is to let SCEVExpander::expand skip the reuse Value logic if CanonicalMode is false. In addition, Besides IndVarSimplify, LSR pass also calls disableCanonicalMode before doing rewrite. We can remove the original check of LSRMode in reuse Value logic and use CanonicalMode instead. llvm-svn: 260174
* Factor out UnrollAnalyzer to Analysis, and add unit tests for it.Michael Zolotukhin2016-02-082-0/+192
| | | | | | | | | | | | | | | | Summary: Unrolling Analyzer is already pretty complicated, and it becomes harder and harder to exercise it with usual IR tests, as with them we can only check the final decision: whether the loop is unrolled or not. This change factors this framework out from LoopUnrollPass to analyses, which allows to use unit tests. The change itself is supposed to be NFC, except adding a couple of tests. I plan to add more tests as I add new functionality and find/fix bugs. Reviewers: chandlerc, hfinkel, sanjoy Subscribers: zzheng, sanjoy, llvm-commits Differential Revision: http://reviews.llvm.org/D16623 llvm-svn: 260169
* [SCEV][LAA] Re-commit r260085 and r260086, this time with a fix for the memorySilviu Baranga2016-02-083-28/+299
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | sanitizer issue. The PredicatedScalarEvolution's copy constructor wasn't copying the Generation value, and was leaving it un-initialized. Original commit message: [SCEV][LAA] Add no wrap SCEV predicates and use use them to improve strided pointer detection Summary: This change adds no wrap SCEV predicates with: - support for runtime checking - support for expression rewriting: (sext ({x,+,y}) -> {sext(x),+,sext(y)} (zext ({x,+,y}) -> {zext(x),+,sext(y)} Note that we are sign extending the increment of the SCEV, even for the zext case. This is needed to cover the fairly common case where y would be a (small) negative integer. In order to do this, this change adds two new flags: nusw and nssw that are applicable to AddRecExprs and permit the transformations above. We also change isStridedPtr in LAA to be able to make use of these predicates. With this feature we should now always be able to work around overflow issues in the dependence analysis. Reviewers: mzolotukhin, sanjoy, anemet Subscribers: mzolotukhin, sanjoy, llvm-commits, rengolin, jmolloy, hfinkel Differential Revision: http://reviews.llvm.org/D15412 llvm-svn: 260112
* Revert r260086 and r260085. They have broken the memorySilviu Baranga2016-02-083-298/+28
| | | | | | sanitizer bots. llvm-svn: 260087
* [SCEV][LAA] Add no wrap SCEV predicates and use use them to improve strided ↵Silviu Baranga2016-02-083-28/+298
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | pointer detection Summary: This change adds no wrap SCEV predicates with: - support for runtime checking - support for expression rewriting: (sext ({x,+,y}) -> {sext(x),+,sext(y)} (zext ({x,+,y}) -> {zext(x),+,sext(y)} Note that we are sign extending the increment of the SCEV, even for the zext case. This is needed to cover the fairly common case where y would be a (small) negative integer. In order to do this, this change adds two new flags: nusw and nssw that are applicable to AddRecExprs and permit the transformations above. We also change isStridedPtr in LAA to be able to make use of these predicates. With this feature we should now always be able to work around overflow issues in the dependence analysis. Reviewers: mzolotukhin, sanjoy, anemet Subscribers: mzolotukhin, sanjoy, llvm-commits, rengolin, jmolloy, hfinkel Differential Revision: http://reviews.llvm.org/D15412 llvm-svn: 260085
* CallAnalyzer::analyzeCall: change the condition back to "Cost < Threshold"Hans Wennborg2016-02-051-1/+1
| | | | | | | | In r252595, I inadvertently changed the condition to "Cost <= Threshold", which caused a significant size regression in Chrome. This commit rectifies that. llvm-svn: 259915
* Fix a regression for r259736.Wei Mi2016-02-041-3/+10
| | | | | | | | | When SCEV expansion tries to reuse an existing value, it is needed to ensure that using the Value at the InsertPt will not break LCSSA. The fix adds a check that InsertPt is either inside the candidate Value's parent loop, or the candidate Value's parent loop is nullptr. llvm-svn: 259815
* [SCEV] Add boolean accessors for NSW, NUW and NW; NFCSanjoy Das2016-02-041-14/+14
| | | | llvm-svn: 259809
* [SCEV] Try to reuse existing value during SCEV expansionWei Mi2016-02-042-5/+113
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Current SCEV expansion will expand SCEV as a sequence of operations and doesn't utilize the value already existed. This will introduce redundent computation which may not be cleaned up throughly by following optimizations. This patch introduces an ExprValueMap which is a map from SCEV to the set of equal values with the same SCEV. When a SCEV is expanded, the set of values is checked and reused whenever possible before generating a sequence of operations. The original commit triggered regressions in Polly tests. The regressions exposed two problems which have been fixed in current version. 1. Polly will generate a new function based on the old one. To generate an instruction for the new function, it builds SCEV for the old instruction, applies some tranformation on the SCEV generated, then expands the transformed SCEV and insert the expanded value into new function. Because SCEV expansion may reuse value cached in ExprValueMap, the value in old function may be inserted into new function, which is wrong. In SCEVExpander::expand, there is a logic to check the cached value to be used should dominate the insertion point. However, for the above case, the check always passes. That is because the insertion point is in a new function, which is unreachable from the old function. However for unreachable node, DominatorTreeBase::dominates thinks it will be dominated by any other node. The fix is to simply add a check that the cached value to be used in expansion should be in the same function as the insertion point instruction. 2. When the SCEV is of scConstant type, expanding it directly is cheaper than reusing a normal value cached. Although in the cached value set in ExprValueMap, there is a Constant type value, but it is not easy to find it out -- the cached Value set is not sorted according to the potential cost. Existing reuse logic in SCEVExpander::expand simply chooses the first legal element from the cached value set. The fix is that when the SCEV is of scConstant type, don't try the reuse logic. simply expand it. Differential Revision: http://reviews.llvm.org/D12090 llvm-svn: 259736
* [ScalarEvolutionExpander] Simplify findInsertPointAfterDavid Majnemer2016-02-031-8/+6
| | | | | | | No functional change is intended. The loop could only execute, at most, once. llvm-svn: 259701
* Revert r259662, which caused regressions on polly tests.Wei Mi2016-02-032-111/+5
| | | | llvm-svn: 259675
* [SCEV] Try to reuse existing value during SCEV expansionWei Mi2016-02-032-5/+111
| | | | | | | | | | | | | | | | Current SCEV expansion will expand SCEV as a sequence of operations and doesn't utilize the value already existed. This will introduce redundent computation which may not be cleaned up throughly by following optimizations. This patch introduces an ExprValueMap which is a map from SCEV to the set of equal values with the same SCEV. When a SCEV is expanded, the set of values is checked and reused whenever possible before generating a sequence of operations. Differential Revision: http://reviews.llvm.org/D12090 llvm-svn: 259662
* [DemandedBits] Revert r249687 due to PR26071James Molloy2016-02-031-7/+0
| | | | | | | | | | | | | | This regresses a test in LoopVectorize, so I'll need to go away and think about how to solve this in a way that isn't broken. From the writeup in PR26071: What's happening is that ComputeKnownZeroes is telling us that all bits except the LSB are zero. We're then deciding that only the LSB needs to be demanded from the icmp's inputs. This is where we're wrong - we're assuming that after simplification the bits that were known zero will continue to be known zero. But they're not - during trivialization the upper bits get changed (because an XOR isn't shrunk), so the icmp fails. The fault is in demandedbits - its contract does clearly state that a non-demanded bit may either be zero or one. llvm-svn: 259649
* [LVI] Fix debug outputPhilip Reames2016-02-021-3/+3
| | | | | | Due to staleness in a patch I committed yesterday, the debug output was reporting overdefined cases as being undefined. Confusing to say the least. The mistake appears to have only effected the debug output thankfully. llvm-svn: 259594
* [LVI] Code motion only [NFC]Philip Reames2016-02-021-64/+62
| | | | | | I introduced a declaration in 259583 to keep the diff readable. This change just moves the definition up to remove the declaration again. llvm-svn: 259585
* [LVI] Refactor to use newly introduced intersect utility Philip Reames2016-02-021-32/+19
| | | | | | | | This patch uses the newly introduced 'intersect' utility (from 259461: [LVI] Introduce an intersect operation on lattice values) to simplify existing code in LVI. While not introducing any new concepts, this change is probably not NFC. The common 'intersect' function is more powerful that the ad-hoc implementations we'd had in a couple of places. Given that, we may see optimizations triggering a bit more often. llvm-svn: 259583
* Fix Clang-tidy readability-redundant-control-flow warnings; other minor fixes.Eugene Zelenko2016-02-021-3/+13
| | | | | | Differential revision: http://reviews.llvm.org/D16793 llvm-svn: 259539
* [LCG] Build an edge abstraction for the LazyCallGraph and use it toChandler Carruth2016-02-021-133/+160
| | | | | | | | | | | | | | | | | | | | | differentiate between indirect references to functions an direct calls. This doesn't do a whole lot yet other than change the print out produced by the analysis, but it lays the groundwork for a very major change I'm working on next: teaching the call graph to actually be a call graph, modeling *both* the indirect reference graph and the call graph simultaneously. More details on that in the next patch though. The rest of this is essentially a bunch of over-engineering that won't be interesting until the next patch. But this also isolates essentially all of the churn necessary to introduce the edge abstraction from the very important behavior change necessary in order to separately model the two graphs. So it should make review of the subsequent patch a bit easier at the cost of making this patch seem poorly motivated. ;] Differential Revision: http://reviews.llvm.org/D16038 llvm-svn: 259463
* [LVI] Introduce an intersect operation on lattice valuesPhilip Reames2016-02-021-32/+85
| | | | | | | | | | | | LVI has several separate sources of facts - edge local conditions, recursive queries, assumes, and control independent value facts - which all apply to the same value at the same location. The existing implementation was very conservative about exploiting all of these facts at once. This change introduces an "intersect" function specifically to abstract the action of picking a good set of facts from all of the separate facts given. At the moment, this function is relatively simple (i.e. mostly just reuses the bits which were already there), but even the minor additions reveal the inherent power. For example, JumpThreading is now capable of doing an inductive proof that a particular value is always positive and removing a half range check. I'm currently only using the new intersect function in one place. If folks are happy with the direction of the work, I plan on making a series of small changes without review to replace mergeIn with intersect at all the appropriate places. Differential Revision: http://reviews.llvm.org/D14476 llvm-svn: 259461
* [LVI] Fix a latent bug in getValueAtPhilip Reames2016-02-021-0/+8
| | | | | | | | This routine was returning Undefined for most queries. This was utterly wrong. Amusingly, we do not appear to have any callers of this which are actually trying to exploit unreachable code or this would have broken the world. A better approach would be to explicit describe the intersection of facts. That's blocked behind http://reviews.llvm.org/D14476 and I wanted to fix the current bug. llvm-svn: 259446
* [LVI] Remove overly tight assert from 259429Philip Reames2016-02-011-2/+2
| | | | | | I'll submit a test case shortly which covers this, but it's causing clang self host problems in the builders so I wanted to get it removed. llvm-svn: 259432
* [LVI] Add select handlingPhilip Reames2016-02-011-0/+49
| | | | | | | | Teach LVI to handle select instructions in the exact same way it handles PHI nodes. This is useful since various parts of the optimizer convert PHI nodes into selects and we don't want these transformations to cause inferior optimization. Note that this patch does nothing to exploit the implied constraint on the inputs represented by the select condition itself. That will be a later patch and is blocked on http://reviews.llvm.org/D14476 llvm-svn: 259429
* Avoid inlining call sites in unreachable-terminated blockJun Bum Lim2016-02-011-6/+17
| | | | | | | | | | | | | Summary: If the normal destination of the invoke or the parent block of the call site is unreachable-terminated, there is little point in inlining the call site unless there is literally zero cost. Unlike my previous change (D15289), this change specifically handle the call sites followed by unreachable in the same basic block for call or in the normal destination for the invoke. This change could be a reasonable first step to conservatively inline call sites leading to an unreachable-terminated block while BFI / BPI is not yet available in inliner. Reviewers: manmanren, majnemer, hfinkel, davidxl, mcrosier, dblaikie, eraman Subscribers: dblaikie, davidxl, mcrosier, llvm-commits Differential Revision: http://reviews.llvm.org/D16616 llvm-svn: 259403
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