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* [PM] Port ScalarEvolution to the new pass manager.Chandler Carruth2015-08-171-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This change makes ScalarEvolution a stand-alone object and just produces one from a pass as needed. Making this work well requires making the object movable, using references instead of overwritten pointers in a number of places, and other refactorings. I've also wired it up to the new pass manager and added a RUN line to a test to exercise it under the new pass manager. This includes basic printing support much like with other analyses. But there is a big and somewhat scary change here. Prior to this patch ScalarEvolution was never *actually* invalidated!!! Re-running the pass just re-wired up the various other analyses and didn't remove any of the existing entries in the SCEV caches or clear out anything at all. This might seem OK as everything in SCEV that can uses ValueHandles to track updates to the values that serve as SCEV keys. However, this still means that as we ran SCEV over each function in the module, we kept accumulating more and more SCEVs into the cache. At the end, we would have a SCEV cache with every value that we ever needed a SCEV for in the entire module!!! Yowzers. The releaseMemory routine would dump all of this, but that isn't realy called during normal runs of the pipeline as far as I can see. To make matters worse, there *is* actually a key that we don't update with value handles -- there is a map keyed off of Loop*s. Because LoopInfo *does* release its memory from run to run, it is entirely possible to run SCEV over one function, then over another function, and then lookup a Loop* from the second function but find an entry inserted for the first function! Ouch. To make matters still worse, there are plenty of updates that *don't* trip a value handle. It seems incredibly unlikely that today GVN or another pass that invalidates SCEV can update values in *just* such a way that a subsequent run of SCEV will incorrectly find lookups in a cache, but it is theoretically possible and would be a nightmare to debug. With this refactoring, I've fixed all this by actually destroying and recreating the ScalarEvolution object from run to run. Technically, this could increase the amount of malloc traffic we see, but then again it is also technically correct. ;] I don't actually think we're suffering from tons of malloc traffic from SCEV because if we were, the fact that we never clear the memory would seem more likely to have come up as an actual problem before now. So, I've made the simple fix here. If in fact there are serious issues with too much allocation and deallocation, I can work on a clever fix that preserves the allocations (while clearing the data) between each run, but I'd prefer to do that kind of optimization with a test case / benchmark that shows why we need such cleverness (and that can test that we actually make it faster). It's possible that this will make some things faster by making the SCEV caches have higher locality (due to being significantly smaller) so until there is a clear benchmark, I think the simple change is best. Differential Revision: http://reviews.llvm.org/D12063 llvm-svn: 245193
* [LAA] Change name from addRuntimeCheck to addRuntimeChecks, NFCAdam Nemet2015-08-111-4/+4
| | | | | | This was requested by Hal in D11205. llvm-svn: 244540
* [LAA] Remove unused pointer partition argument from needsChecking(), NFCAdam Nemet2015-08-091-10/+4
| | | | | | | This is no longer used in any of the callers. Also remove the logic of handling this argument. llvm-svn: 244421
* [LAA] Remove unused pointer partition argument from generateChecks, NFCAdam Nemet2015-08-091-3/+2
| | | | | | LoopDistribution does its own filtering now. llvm-svn: 244420
* [LAA] Remove unused pointer partition argument from getNumberOfChecks, NFCAdam Nemet2015-08-071-14/+1
| | | | | | | | | This is unused after filtering checks was moved to the clients. As a result, we can just return the number of the checks in the precomputed set. llvm-svn: 244369
* [LAA] Make the set of runtime checks part of the state of LAA, NFCAdam Nemet2015-08-071-3/+10
| | | | | | | | | | | | | | | | | | | | This is the full set of checks that clients can further filter. IOW, it's client-agnostic. This makes LAA complete in the sense that it now provides the two main results of its analysis precomputed: 1. memory dependences via getDepChecker().getInsterestingDependences() 2. run-time checks via getRuntimePointerCheck().getChecks() However, as a consequence we now compute this information pro-actively. Thus if the client decides to skip the loop based on the dependences we've computed the checks unnecessarily. In order to see whether this was a significant overhead I checked compile time on SPEC2k6 LTO bitcode files. The change was in the noise. The checks are generated in canCheckPtrAtRT, at the same place where we used to call groupChecks to merge checks. llvm-svn: 244368
* [LAA] Remove unused pointer partition argument from print(), NFCAdam Nemet2015-08-071-4/+2
| | | | | | | This is now handled in the client. No need for LAA to provide this variant. llvm-svn: 244349
* [LAA] Remove unused pointer partition argument from addRuntimeCheck, NFCAdam Nemet2015-08-041-2/+2
| | | | | | | This variant of addRuntimeCheck is only used now from the LoopVectorizer which does not use this parameter. llvm-svn: 243955
* [LAA] Remove unused needsAnyChecking(), NFCAdam Nemet2015-08-031-11/+0
| | | | llvm-svn: 243921
* De-constify pointers to Type since they can't be modified. NFCCraig Topper2015-08-011-2/+2
| | | | | | This was already done in most places a while ago. This just fixes the ones that crept in over time. llvm-svn: 243842
* [LAA] Add clarifying comments for the checking pointer grouping algorithm. NFCSilviu Baranga2015-07-281-1/+24
| | | | llvm-svn: 243416
* [LAA] Split out a helper to print a collection of memchecksAdam Nemet2015-07-271-34/+27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is effectively an NFC but we can no longer print the index of the pointer group so instead I print its address. This still lets us cross-check the section that list the checks against the section that list the groups (see how I modified the test). E.g. before we printed this: Run-time memory checks: Check 0: Comparing group 0: %arrayidxC = getelementptr inbounds i16, i16* %c, i64 %store_ind %arrayidxC1 = getelementptr inbounds i16, i16* %c, i64 %store_ind_inc Against group 1: %arrayidxA = getelementptr i16, i16* %a, i64 %ind %arrayidxA1 = getelementptr i16, i16* %a, i64 %add ... Grouped accesses: Group 0: (Low: %c High: (78 + %c)) Member: {%c,+,4}<%for.body> Member: {(2 + %c),+,4}<%for.body> Now we print this (changes are underlined): Run-time memory checks: Check 0: Comparing group (0x7f9c6040c320): ~~~~~~~~~~~~~~ %arrayidxC1 = getelementptr inbounds i16, i16* %c, i64 %store_ind_inc %arrayidxC = getelementptr inbounds i16, i16* %c, i64 %store_ind Against group (0x7f9c6040c358): ~~~~~~~~~~~~~~ %arrayidxA1 = getelementptr i16, i16* %a, i64 %add %arrayidxA = getelementptr i16, i16* %a, i64 %ind ... Grouped accesses: Group 0x7f9c6040c320: ~~~~~~~~~~~~~~ (Low: %c High: (78 + %c)) Member: {(2 + %c),+,4}<%for.body> Member: {%c,+,4}<%for.body> llvm-svn: 243354
* [LAA] Upper-case variable names, NFCAdam Nemet2015-07-271-4/+4
| | | | llvm-svn: 243313
* [LAA] Split out a helper from addRuntimeCheck to generate the check, NFCAdam Nemet2015-07-271-14/+18
| | | | llvm-svn: 243312
* LoopAccessAnalysis.cpp: Tweak r243239 to avoid side effects. It caused ↵NAKAMURA Takumi2015-07-271-3/+4
| | | | | | different emissions between gcc and clang. llvm-svn: 243258
* [LAA] Begin moving the logic of generating checks out of addRuntimeCheckAdam Nemet2015-07-261-69/+111
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: The goal is to start moving us closer to the model where RuntimePointerChecking will compute and store the checks. Then a client can filter the check according to its requirements and then use the filtered list of checks with addRuntimeCheck. Before the patch, this is all done in addRuntimeCheck. So the patch starts to split up addRuntimeCheck while providing the old API under what's more or less a wrapper now. The new underlying addRuntimeCheck takes a collection of checks now, expands the code for the bounds then generates the code for the checks. I am not completely happy with making expandBounds static because now it needs so many explicit arguments but I don't want to make the type PointerBounds part of LAI. This should get fixed when addRuntimeCheck is moved to LoopVersioning where it really belongs, IMO. Audited the assembly diff of the testsuite (including externals). There is a tiny bit of assembly churn that is due to the different order the code for the bounds is expanded now (MultiSource/Benchmarks/Prolangs-C/bison/conflicts.s and with LoopDist on 456.hmmer/fast_algorithms.s). Reviewers: hfinkel Subscribers: klimek, llvm-commits Differential Revision: http://reviews.llvm.org/D11205 llvm-svn: 243239
* Fix memcheck interval ends for pointers with negative stridesSilviu Baranga2015-07-161-2/+18
| | | | | | | | | | | | | | | | | | | | | | | | Summary: The checking pointer grouping algorithm assumes that the starts/ends of the pointers are well formed (start <= end). The runtime memory checking algorithm also assumes this by doing: start0 < end1 && start1 < end0 to detect conflicts. This check only works if start0 <= end0 and start1 <= end1. This change correctly orders the interval ends by either checking the stride (if it is constant) or by using min/max SCEV expressions. Reviewers: anemet, rengolin Subscribers: rengolin, llvm-commits Differential Revision: http://reviews.llvm.org/D11149 llvm-svn: 242400
* [LAA] Split out a helper to check the pointer partitions, NFCAdam Nemet2015-07-161-4/+8
| | | | | | | | | This is made a static public member function to allow the transition of this logic from LAA to LoopDistribution. (Technically, it could be an implementation-local static function but then it would not be accessible from LoopDistribution.) llvm-svn: 242376
* [LAA] Introduce RuntimePointerChecking::PointerInfo, NFCAdam Nemet2015-07-141-29/+33
| | | | | | | Turn this structure-of-arrays (i.e. the various pointer attributes) into array-of-structures. llvm-svn: 242219
* [LAA] Lift RuntimePointerCheck out of LoopAccessInfo, NFCAdam Nemet2015-07-141-43/+41
| | | | | | | | | I am planning to add more nested classes inside RuntimePointerCheck so all these triple-nesting would be hard to follow. Also rename it to RuntimePointerChecking (i.e. append 'ing'). llvm-svn: 242218
* Cleanup after r241809 - remove uncessary call to std::sortSilviu Baranga2015-07-131-10/+5
| | | | | | | | | | | | | | Summary: The iteration order within a member of DepCands is deterministic and therefore we don't have to sort the accesses within a member. We also don't have to copy the indices of the pointers into a vector, since we can iterate over the members of the class. Subscribers: llvm-commits Differential Revision: http://reviews.llvm.org/D11145 llvm-svn: 242033
* [LAA] Fix grammar in debug outputAdam Nemet2015-07-091-1/+1
| | | | llvm-svn: 241867
* [LAA] Hide NeedRTCheck logic completely inside canCheckPtrAtRT, NFCAdam Nemet2015-07-091-31/+27
| | | | | | | | | | | | | | | | | | | | | | | | | | | Currently canCheckPtrAtRT returns two flags NeedRTCheck and CanDoRT. NeedRTCheck says whether we need checks and CanDoRT whether we can generate the checks. The idea is to encode three states with these: Need/Can: (1) false/dont-care: no checks are needed (2) true/false: we need checks but can't generate them (3) true/true: we need checks and we can generate them This is pretty unnecessary since the caller (analyzeLoop) is only interested in whether we can generate the checks if we actually need them (i.e. 1 or 3). So this change cleans up to return just that (CanDoRTIfNeeded) and pulls all the underlying logic into canCheckPtrAtRT. By doing all this, we simplify analyzeLoop which is the complex function in LAA. There is further room for improvement here by using RtCheck.Need directly rather than a new local variable NeedRTCheck but that's for a later patch. llvm-svn: 241866
* Don't rely on the DepCands iteration order when constructing checking ↵Silviu Baranga2015-07-091-4/+26
| | | | | | | | | | | | | | | | | | | pointer groups Summary: The checking pointer group construction algorithm relied on the iteration on DepCands. We would need the same leaders across runs and the same iteration order over the underlying std::set for determinism. This changes the algorithm to process the pointers in the order in which they were added to the runtime check, which is deterministic. We need to update the tests, since the order in which pointers appear has changed. No new tests were added, since it is impossible to test for non-determinism. Subscribers: llvm-commits Differential Revision: http://reviews.llvm.org/D11064 llvm-svn: 241809
* [LAA] Fix line break in commentAdam Nemet2015-07-091-1/+1
| | | | llvm-svn: 241785
* [LAA] Rename IsRTNeeded to IsRTCheckAnalysisNeededAdam Nemet2015-07-091-6/+17
| | | | | | | | | | | | The original name was too close to NeedRTCheck which is what the actual memcheck analysis returns. This flag, as the new name suggests, is only used to whether to initiate that analysis. Also a comment is added to answer one question I had about this code for a long time. Namely, how does this flag differ from isDependencyCheckNeeded since they are seemingly set at the same time. llvm-svn: 241784
* [LAA] Fix misleading use of word 'consecutive'Adam Nemet2015-07-091-3/+3
| | | | | | | Fix some places where the word consecutive is used but the code really means constant-stride (i.e. not just unit stride). llvm-svn: 241763
* [LAA] Revert a small part of r239295Adam Nemet2015-07-081-6/+20
| | | | | | | | | | | | | | | | This commit ([LAA] Fix estimation of number of memchecks) regressed the logic a bit. We shouldn't quit the analysis if we encounter a pointer without known bounds *unless* we actually need to emit a memcheck for it. The original code was using NumComparisons which is now computed differently. Instead I compute NeedRTCheck from NumReadPtrChecks and NumWritePtrChecks. As side note, I find the separation of NeedRTCheck and CanDoRT confusing, so I will try to merge them in a follow-up patch. llvm-svn: 241756
* [LAA] Add missing debug output after r239285Adam Nemet2015-07-081-1/+3
| | | | | | | | | r239285 ([LoopAccessAnalysis] Teach LAA to check the memory dependence between strided accesses.) introduced a new case under MemoryDepChecker::isDependent. We normally have debug output for each case. llvm-svn: 241707
* [LAA] Merge memchecks for accesses separated by a constant offsetSilviu Baranga2015-07-081-38/+215
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: Often filter-like loops will do memory accesses that are separated by constant offsets. In these cases it is common that we will exceed the threshold for the allowable number of checks. However, it should be possible to merge such checks, sice a check of any interval againt two other intervals separated by a constant offset (a,b), (a+c, b+c) will be equivalent with a check againt (a, b+c), as long as (a,b) and (a+c, b+c) overlap. Assuming the loop will be executed for a sufficient number of iterations, this will be true. If not true, checking against (a, b+c) is still safe (although not equivalent). As long as there are no dependencies between two accesses, we can merge their checks into a single one. We use this technique to construct groups of accesses, and then check the intervals associated with the groups instead of checking the accesses directly. Reviewers: anemet Subscribers: llvm-commits Differential Revision: http://reviews.llvm.org/D10386 llvm-svn: 241673
* Move VectorUtils from Transforms to Analysis to correct layering violationDavid Blaikie2015-06-261-1/+1
| | | | llvm-svn: 240804
* [LAA] Try to prove non-wrapping of pointers if SCEV cannotAdam Nemet2015-06-261-1/+49
| | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: Scalar evolution does not propagate the non-wrapping flags to values that are derived from a non-wrapping induction variable because the non-wrapping property could be flow-sensitive. This change is a first attempt to establish the non-wrapping property in some simple cases. The main idea is to look through the operations defining the pointer. As long as we arrive to a non-wrapping AddRec via a small chain of non-wrapping instruction, the pointer should not wrap either. I believe that this essentially is what Andy described in http://article.gmane.org/gmane.comp.compilers.llvm.cvs/220731 as the way forward. Reviewers: aschwaighofer, nadav, sanjoy, atrick Reviewed By: atrick Subscribers: llvm-commits Differential Revision: http://reviews.llvm.org/D10472 llvm-svn: 240798
* [PM/AA] Remove the UnknownSize static member from AliasAnalysis.Chandler Carruth2015-06-171-2/+2
| | | | | | | | This is now living in MemoryLocation, which is what it pertains to. It is also an enum there rather than a static data member which is left never defined. llvm-svn: 239886
* [PM/AA] Remove the Location typedef from the AliasAnalysis class nowChandler Carruth2015-06-171-4/+4
| | | | | | | | | | | | that it is its own entity in the form of MemoryLocation, and update all the callers. This is an entirely mechanical change. References to "Location" within AA subclases become "MemoryLocation", and elsewhere "AliasAnalysis::Location" becomes "MemoryLocation". Hope that helps out-of-tree folks update. llvm-svn: 239885
* [LAA] Fix estimation of number of memchecksSilviu Baranga2015-06-081-38/+34
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: We need to add a runtime memcheck for pair of accesses (x,y) where at least one of x and y are writes. Assuming we have w writes and r reads, currently this number is estimated as being w* (w+r-1). This estimation will count (write,write) pairs twice and will overestimate the number of checks required. This change adds a getNumberOfChecks method to RuntimePointerCheck, which will count the number of runtime checks needed (similar in implementation to needsAnyChecking) and uses it to produce the correct number of runtime checks. Test Plan: llvm test suite spec2k spec2k6 Performance results: no changes observed (not surprising since the formula for 1 writer is basically the same, which would covers most cases - at least with the current check limit). Reviewers: anemet Reviewed By: anemet Subscribers: mzolotukhin, llvm-commits Differential Revision: http://reviews.llvm.org/D10217 llvm-svn: 239295
* [LoopVectorize] Teach Loop Vectorizor about interleaved memory accesses.Hao Liu2015-06-081-7/+2
| | | | | | | | | | | | | | | | | | | | | | | | Interleaved memory accesses are grouped and vectorized into vector load/store and shufflevector. E.g. for (i = 0; i < N; i+=2) { a = A[i]; // load of even element b = A[i+1]; // load of odd element ... // operations on a, b, c, d A[i] = c; // store of even element A[i+1] = d; // store of odd element } The loads of even and odd elements are identified as an interleave load group, which will be transfered into vectorized IRs like: %wide.vec = load <8 x i32>, <8 x i32>* %ptr %vec.even = shufflevector <8 x i32> %wide.vec, <8 x i32> undef, <4 x i32> <i32 0, i32 2, i32 4, i32 6> %vec.odd = shufflevector <8 x i32> %wide.vec, <8 x i32> undef, <4 x i32> <i32 1, i32 3, i32 5, i32 7> The stores of even and odd elements are identified as an interleave store group, which will be transfered into vectorized IRs like: %interleaved.vec = shufflevector <4 x i32> %vec.even, %vec.odd, <8 x i32> <i32 0, i32 4, i32 1, i32 5, i32 2, i32 6, i32 3, i32 7> store <8 x i32> %interleaved.vec, <8 x i32>* %ptr This optimization is currently disabled by defaut. To try it by adding '-enable-interleaved-mem-accesses=true'. llvm-svn: 239291
* [LoopAccessAnalysis] Teach LAA to check the memory dependence between ↵Hao Liu2015-06-081-12/+101
| | | | | | | | strided accesses. Differential Revision: http://reviews.llvm.org/D9368 llvm-svn: 239285
* [PM/AA] Start refactoring AliasAnalysis to remove the analysis group andChandler Carruth2015-06-041-2/+2
| | | | | | | | | | | | | | | | | | | | | port it to the new pass manager. All this does is extract the inner "location" class used by AA into its own full fledged type. This seems *much* cleaner as MemoryDependence and soon MemorySSA also use this heavily, and it doesn't make much sense being inside the AA infrastructure. This will also make it much easier to break apart the AA infrastructure into something that stands on its own rather than using the analysis group design. There are a few places where this makes APIs not make sense -- they were taking an AliasAnalysis pointer just to build locations. I'll try to clean those up in follow-up commits. Differential Revision: http://reviews.llvm.org/D10228 llvm-svn: 239003
* [LoopAccesses] If shouldRetryWithRuntimeCheck, reset InterestingDependencesAdam Nemet2015-05-181-2/+7
| | | | | | | | When dependence analysis encounters a non-constant distance between memory accesses it aborts the analysis and falls back to run-time checks only. In this case we weren't resetting the array of dependences. llvm-svn: 237574
* [LoopAccesses] Rearrange printed lines in -analyzeAdam Nemet2015-05-181-4/+4
| | | | | | | "Store to invariant address..." is moved as the last line. This is not the prime result of the analysis. Plus it simplifies some of the tests. llvm-svn: 237573
* [LoopAccesses] Debug improvementAdam Nemet2015-05-181-0/+1
| | | | | | Report pointers with unknown bounds. llvm-svn: 237572
* [getUnderlyingOjbects] Analyze loop PHIs further to remove false positivesAdam Nemet2015-04-231-8/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Specifically, if a pointer accesses different underlying objects in each iteration, don't look through the phi node defining the pointer. The motivating case is the underlyling-objects-2.ll testcase. Consider the loop nest: int **A; for (i) for (j) A[i][j] = A[i-1][j] * B[j] This loop is transformed by Load-PRE to stash away A[i] for the next iteration of the outer loop: Curr = A[0]; // Prev_0 for (i: 1..N) { Prev = Curr; // Prev = PHI (Prev_0, Curr) Curr = A[i]; for (j: 0..N) Curr[j] = Prev[j] * B[j] } Since A[i] and A[i-1] are likely to be independent pointers, getUnderlyingObjects should not assume that Curr and Prev share the same underlying object in the inner loop. If it did we would try to dependence-analyze Curr and Prev and the analysis of the corresponding SCEVs would fail with non-constant distance. To fix this, the getUnderlyingObjects API is extended with an optional LoopInfo parameter. This is effectively what controls whether we want the above behavior or the original. Currently, I only changed to use this approach for LoopAccessAnalysis. The other testcase is to guard the opposite case where we do want to look through the loop PHI. If we step through an array by incrementing a pointer, the underlying object is the incoming value of the phi as the loop is entered. Fixes rdar://problem/19566729 llvm-svn: 235634
* [LoopAccesses] Improve debug outputAdam Nemet2015-04-171-4/+8
| | | | llvm-svn: 235238
* [LoopAccesses] Properly print whether memchecks are neededAdam Nemet2015-04-141-3/+3
| | | | | | | | | | | Fix oversight in -analyze output. PtrRtCheck contains the pointers that need to be checked against each other and not whether memchecks are necessary. For instance in the testcase PtrRtCheck has four elements but all no-alias so no checking is necessary. llvm-svn: 234833
* [LoopAccesses] Allow analysis to complete in the presence of uniform storesAdam Nemet2015-04-081-11/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | (Re-apply r234361 with a fix and a testcase for PR23157) Both run-time pointer checking and the dependence analysis are capable of dealing with uniform addresses. I.e. it's really just an orthogonal property of the loop that the analysis computes. Run-time pointer checking will only try to reason about SCEVAddRec pointers or else gives up. If the uniform pointer turns out the be a SCEVAddRec in an outer loop, the run-time checks generated will be correct (start and end bounds would be equal). In case of the dependence analysis, we work again with SCEVs. When compared against a loop-dependent address of the same underlying object, the difference of the two SCEVs won't be constant. This will result in returning an Unknown dependence for the pair. When compared against another uniform access, the difference would be constant and we should return the right type of dependence (forward/backward/etc). The changes also adds support to query this property of the loop and modify the vectorizer to use this. Patch by Ashutosh Nema! llvm-svn: 234424
* Revert "[LoopAccesses] Allow analysis to complete in the presence of uniform ↵Adam Nemet2015-04-081-8/+11
| | | | | | | | | | stores" This reverts commit r234361. It caused PR23157. llvm-svn: 234387
* [LoopAccesses] Allow analysis to complete in the presence of uniform storesAdam Nemet2015-04-071-11/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | Both run-time pointer checking and the dependence analysis are capable of dealing with uniform addresses. I.e. it's really just an orthogonal property of the loop that the analysis computes. Run-time pointer checking will only try to reason about SCEVAddRec pointers or else gives up. If the uniform pointer turns out the be a SCEVAddRec in an outer loop, the run-time checks generated will be correct (start and end bounds would be equal). In case of the dependence analysis, we work again with SCEVs. When compared against a loop-dependent address of the same underlying object, the difference of the two SCEVs won't be constant. This will result in returning an Unknown dependence for the pair. When compared against another uniform access, the difference would be constant and we should return the right type of dependence (forward/backward/etc). The changes also adds support to query this property of the loop and modify the vectorizer to use this. Patch by Ashutosh Nema! llvm-svn: 234361
* [LoopAccesses] New API to query if memchecks are necessary after partitioningAdam Nemet2015-04-071-0/+11
| | | | | | This is used by Loop Distribution. llvm-svn: 234283
* [LoopAccesses] Handle case when no memchecks are needed after partitioningAdam Nemet2015-04-021-2/+4
| | | | llvm-svn: 233930
* Re-sort includes with sort-includes.py and insert raw_ostream.h where it's used.Benjamin Kramer2015-03-231-1/+2
| | | | llvm-svn: 232998
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