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* Transforms: Fix bootstrap after r266565Duncan P. N. Exon Smith2016-04-171-1/+1
| | | | | | | | | | | | Apparently there isn't test coverage for all of these. I'd appreciate if someone with could reproduce and send me something to reduce, but for now I've just looked for users of RemapInstruction and MapValue and ensured they don't accidentally insert nullptr. Here is one of the bootstraps that caught: http://lab.llvm.org:8011/builders/clang-x64-ninja-win7/builds/11494 llvm-svn: 266567
* IR: RF_IgnoreMissingValues => RF_IgnoreMissingLocals, NFCDuncan P. N. Exon Smith2016-04-071-1/+1
| | | | | | | | | | | | | | | | | | | | | | | Clarify what this RemapFlag actually means. - Change the flag name to match its intended behaviour. - Clearly document that it's not supposed to affect globals. - Add a host of FIXMEs to indicate how to fix the behaviour to match the intent of the flag. RF_IgnoreMissingLocals should only affect the behaviour of RemapInstruction for function-local operands; namely, for operands of type Argument, Instruction, and BasicBlock. Currently, it is *only* passed into RemapInstruction calls (and the transitive MapValue calls that it makes). When I split Metadata from Value I didn't understand the flag, and I used it in a bunch of places for "global" metadata. This commit doesn't have any functionality change, but prepares to cleanup MapMetadata and MapValue. llvm-svn: 265628
* [LPM] Factor all of the loop analysis usage updates into a common helperChandler Carruth2016-02-191-19/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | routine. We were getting this wrong in small ways and generally being very inconsistent about it across loop passes. Instead, let's have a common place where we do this. One minor downside is that this will require some analyses like SCEV in more places than they are strictly needed. However, this seems benign as these analyses are complete no-ops, and without this consistency we can in many cases end up with the legacy pass manager scheduling deciding to split up a loop pass pipeline in order to run the function analysis half-way through. It is very, very annoying to fix these without just being very pedantic across the board. The only loop passes I've not updated here are ones that use AU.setPreservesAll() such as IVUsers (an analysis) and the pass printer. They seemed less relevant. With this patch, almost all of the problems in PR24804 around loop pass pipelines are fixed. The one remaining issue is that we run simplify-cfg and instcombine in the middle of the loop pass pipeline. We've recently added some loop variants of these passes that would seem substantially cleaner to use, but this at least gets us much closer to the previous state. Notably, the seven loop pass managers is down to three. I've not updated the loop passes using LoopAccessAnalysis because that analysis hasn't been fully wired into LoopSimplify/LCSSA, and it isn't clear that those transforms want to support those forms anyways. They all run late anyways, so this is harmless. Similarly, LSR is left alone because it already carefully manages its forms and doesn't need to get fused into a single loop pass manager with a bunch of other loop passes. LoopReroll didn't use loop simplified form previously, and I've updated the test case to match the trivially different output. Finally, I've also factored all the pass initialization for the passes that use this technique as well, so that should be done regularly and reliably. Thanks to James for the help reviewing and thinking about this stuff, and Ben for help thinking about it as well! Differential Revision: http://reviews.llvm.org/D17435 llvm-svn: 261316
* [LoopRotate] Don't perform loop rotation if the loop header calls a ↵Justin Lebar2016-02-121-0/+5
| | | | | | | | | | | | | | | | | convergent function. Summary: Calls to convergent functions can be duplicated, but only if the duplicates are not control-flow dependent on any additional values. Loop rotation doesn't meet the bar. Reviewers: jingyue Subscribers: mzolotukhin, llvm-commits, arsenm, joker.eph, resistor, tra, hfinkel, broune Differential Revision: http://reviews.llvm.org/D17127 llvm-svn: 260729
* LoopRotate: Convert the methods of LoopRotate to utility functions. NFCJustin Bogner2015-12-141-79/+82
| | | | | | | | | | This moves the actual work to do loop rotation into standalone functions with the analysis results they need passed in as arguments, leaving the class itself as a relatively simple shim. This will make the functions easy to reuse when we're ready to port this transformation to the new pass manager. llvm-svn: 255574
* LoopRotate: Reorder some method implementations. NFCJustin Bogner2015-12-141-159/+159
| | | | | | | | | | This just moves some callers after their callees. My next patch will convert some of these methods to stand alone functions, and that diff is more obviously NFC if I move these first. That change, in turn, will make it much easier to port this pass to the new pass manager once the loop pass manager is in place. llvm-svn: 255573
* Scalar: Remove remaining ilist iterator implicit conversionsDuncan P. N. Exon Smith2015-10-131-5/+6
| | | | | | | | | | | | | | | | | | | Remove remaining `ilist_iterator` implicit conversions from LLVMScalarOpts. This change exposed some scary behaviour in lib/Transforms/Scalar/SCCP.cpp around line 1770. This patch changes a call from `Function::begin()` to `&Function::front()`, since the return was immediately being passed into another function that takes a `Function*`. `Function::front()` started to assert, since the function was empty. Note that `Function::end()` does not point at a legal `Function*` -- it points at an `ilist_half_node` -- so the other function was getting garbage before. (I added the missing check for `Function::isDeclaration()`.) Otherwise, no functionality change intended. llvm-svn: 250211
* [PM/AA] Rebuild LLVM's alias analysis infrastructure in a way compatibleChandler Carruth2015-09-091-1/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | with the new pass manager, and no longer relying on analysis groups. This builds essentially a ground-up new AA infrastructure stack for LLVM. The core ideas are the same that are used throughout the new pass manager: type erased polymorphism and direct composition. The design is as follows: - FunctionAAResults is a type-erasing alias analysis results aggregation interface to walk a single query across a range of results from different alias analyses. Currently this is function-specific as we always assume that aliasing queries are *within* a function. - AAResultBase is a CRTP utility providing stub implementations of various parts of the alias analysis result concept, notably in several cases in terms of other more general parts of the interface. This can be used to implement only a narrow part of the interface rather than the entire interface. This isn't really ideal, this logic should be hoisted into FunctionAAResults as currently it will cause a significant amount of redundant work, but it faithfully models the behavior of the prior infrastructure. - All the alias analysis passes are ported to be wrapper passes for the legacy PM and new-style analysis passes for the new PM with a shared result object. In some cases (most notably CFL), this is an extremely naive approach that we should revisit when we can specialize for the new pass manager. - BasicAA has been restructured to reflect that it is much more fundamentally a function analysis because it uses dominator trees and loop info that need to be constructed for each function. All of the references to getting alias analysis results have been updated to use the new aggregation interface. All the preservation and other pass management code has been updated accordingly. The way the FunctionAAResultsWrapperPass works is to detect the available alias analyses when run, and add them to the results object. This means that we should be able to continue to respect when various passes are added to the pipeline, for example adding CFL or adding TBAA passes should just cause their results to be available and to get folded into this. The exception to this rule is BasicAA which really needs to be a function pass due to using dominator trees and loop info. As a consequence, the FunctionAAResultsWrapperPass directly depends on BasicAA and always includes it in the aggregation. This has significant implications for preserving analyses. Generally, most passes shouldn't bother preserving FunctionAAResultsWrapperPass because rebuilding the results just updates the set of known AA passes. The exception to this rule are LoopPass instances which need to preserve all the function analyses that the loop pass manager will end up needing. This means preserving both BasicAAWrapperPass and the aggregating FunctionAAResultsWrapperPass. Now, when preserving an alias analysis, you do so by directly preserving that analysis. This is only necessary for non-immutable-pass-provided alias analyses though, and there are only three of interest: BasicAA, GlobalsAA (formerly GlobalsModRef), and SCEVAA. Usually BasicAA is preserved when needed because it (like DominatorTree and LoopInfo) is marked as a CFG-only pass. I've expanded GlobalsAA into the preserved set everywhere we previously were preserving all of AliasAnalysis, and I've added SCEVAA in the intersection of that with where we preserve SCEV itself. One significant challenge to all of this is that the CGSCC passes were actually using the alias analysis implementations by taking advantage of a pretty amazing set of loop holes in the old pass manager's analysis management code which allowed analysis groups to slide through in many cases. Moving away from analysis groups makes this problem much more obvious. To fix it, I've leveraged the flexibility the design of the new PM components provides to just directly construct the relevant alias analyses for the relevant functions in the IPO passes that need them. This is a bit hacky, but should go away with the new pass manager, and is already in many ways cleaner than the prior state. Another significant challenge is that various facilities of the old alias analysis infrastructure just don't fit any more. The most significant of these is the alias analysis 'counter' pass. That pass relied on the ability to snoop on AA queries at different points in the analysis group chain. Instead, I'm planning to build printing functionality directly into the aggregation layer. I've not included that in this patch merely to keep it smaller. Note that all of this needs a nearly complete rewrite of the AA documentation. I'm planning to do that, but I'd like to make sure the new design settles, and to flesh out a bit more of what it looks like in the new pass manager first. Differential Revision: http://reviews.llvm.org/D12080 llvm-svn: 247167
* [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
* Convert a bunch of loops to foreach. NFC.Pete Cooper2015-08-061-2/+2
| | | | | | | | After r244074, we now have a successors() method to iterate over all the successors of a TerminatorInst. This commit changes a bunch of eligible loops to use it. llvm-svn: 244260
* [GMR] Add a late run of GlobalsModRef to the main pass pipeline behindChandler Carruth2015-07-231-0/+2
| | | | | | | | | | | | | | | | | | | the general GMR-in-non-LTO flag. Without this, we have the global information during the CGSCC pipeline for GVN and such, but don't have it available during the late loop optimizations such as the vectorizer. Moreover, after the CGSCC pipeline has finished we have substantially more accurate and refined call graph information, function annotations, etc, which will make GMR even more powerful than it is early in the pipelien. Note that we have to play silly games with preserving AliasAnalysis (which is now trivially preserved) in order to let a module analysis magically be preserved into the entire function pass pipeline. Simultaneously we have to not make GMR an immutable pass in order to be able to re-run it and collect fresh data on the final call graph. llvm-svn: 242999
* 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
* Re-sort includes with sort-includes.py and insert raw_ostream.h where it's used.Benjamin Kramer2015-03-231-0/+1
| | | | llvm-svn: 232998
* DataLayout is mandatory, update the API to reflect it with references.Mehdi Amini2015-03-101-2/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: Now that the DataLayout is a mandatory part of the module, let's start cleaning the codebase. This patch is a first attempt at doing that. This patch is not exactly NFC as for instance some places were passing a nullptr instead of the DataLayout, possibly just because there was a default value on the DataLayout argument to many functions in the API. Even though it is not purely NFC, there is no change in the validation. I turned as many pointer to DataLayout to references, this helped figuring out all the places where a nullptr could come up. I had initially a local version of this patch broken into over 30 independant, commits but some later commit were cleaning the API and touching part of the code modified in the previous commits, so it seemed cleaner without the intermediate state. Test Plan: Reviewers: echristo Subscribers: llvm-commits From: Mehdi Amini <mehdi.amini@apple.com> llvm-svn: 231740
* LoopRotate: When reconstructing loop simplify form don't split edges from ↵Benjamin Kramer2015-02-201-0/+2
| | | | | | | | | | | | indirectbrs. Yet another chapter in the endless story. While this looks like we leave the loop in a non-canonical state this replicates the logic in LoopSimplify so it doesn't diverge from the canonical form in any way. PR21968 llvm-svn: 230058
* [multiversion] Thread a function argument through all the callers of theChandler Carruth2015-02-011-3/+4
| | | | | | | | | | | | | | getTTI method used to get an actual TTI object. No functionality changed. This just threads the argument and ensures code like the inliner can correctly look up the callee's TTI rather than using a fixed one. The next change will use this to implement per-function subtarget usage by TTI. The changes after that should eliminate the need for FTTI as that will have become the default. llvm-svn: 227730
* [PM] Change the core design of the TTI analysis to use a polymorphicChandler Carruth2015-01-311-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | type erased interface and a single analysis pass rather than an extremely complex analysis group. The end result is that the TTI analysis can contain a type erased implementation that supports the polymorphic TTI interface. We can build one from a target-specific implementation or from a dummy one in the IR. I've also factored all of the code into "mix-in"-able base classes, including CRTP base classes to facilitate calling back up to the most specialized form when delegating horizontally across the surface. These aren't as clean as I would like and I'm planning to work on cleaning some of this up, but I wanted to start by putting into the right form. There are a number of reasons for this change, and this particular design. The first and foremost reason is that an analysis group is complete overkill, and the chaining delegation strategy was so opaque, confusing, and high overhead that TTI was suffering greatly for it. Several of the TTI functions had failed to be implemented in all places because of the chaining-based delegation making there be no checking of this. A few other functions were implemented with incorrect delegation. The message to me was very clear working on this -- the delegation and analysis group structure was too confusing to be useful here. The other reason of course is that this is *much* more natural fit for the new pass manager. This will lay the ground work for a type-erased per-function info object that can look up the correct subtarget and even cache it. Yet another benefit is that this will significantly simplify the interaction of the pass managers and the TargetMachine. See the future work below. The downside of this change is that it is very, very verbose. I'm going to work to improve that, but it is somewhat an implementation necessity in C++ to do type erasure. =/ I discussed this design really extensively with Eric and Hal prior to going down this path, and afterward showed them the result. No one was really thrilled with it, but there doesn't seem to be a substantially better alternative. Using a base class and virtual method dispatch would make the code much shorter, but as discussed in the update to the programmer's manual and elsewhere, a polymorphic interface feels like the more principled approach even if this is perhaps the least compelling example of it. ;] Ultimately, there is still a lot more to be done here, but this was the huge chunk that I couldn't really split things out of because this was the interface change to TTI. I've tried to minimize all the other parts of this. The follow up work should include at least: 1) Improving the TargetMachine interface by having it directly return a TTI object. Because we have a non-pass object with value semantics and an internal type erasure mechanism, we can narrow the interface of the TargetMachine to *just* do what we need: build and return a TTI object that we can then insert into the pass pipeline. 2) Make the TTI object be fully specialized for a particular function. This will include splitting off a minimal form of it which is sufficient for the inliner and the old pass manager. 3) Add a new pass manager analysis which produces TTI objects from the target machine for each function. This may actually be done as part of #2 in order to use the new analysis to implement #2. 4) Work on narrowing the API between TTI and the targets so that it is easier to understand and less verbose to type erase. 5) Work on narrowing the API between TTI and its clients so that it is easier to understand and less verbose to forward. 6) Try to improve the CRTP-based delegation. I feel like this code is just a bit messy and exacerbating the complexity of implementing the TTI in each target. Many thanks to Eric and Hal for their help here. I ended up blocked on this somewhat more abruptly than I expected, and so I appreciate getting it sorted out very quickly. Differential Revision: http://reviews.llvm.org/D7293 llvm-svn: 227669
* LoopRotate: Don't walk the uses of a ConstantDavid Majnemer2015-01-271-11/+8
| | | | | | | | | | LoopRotate wanted to avoid live range interference by looking at the uses of a Value in the loop latch and seeing if any lied outside of the loop. We would wrongly perform this operation on Constants. This fixes PR22337. llvm-svn: 227171
* [PM] Remove the Pass argument from all of the critical edge splittingChandler Carruth2015-01-191-2/+5
| | | | | | | | | | | | | | | | | | | APIs and replace it and numerous booleans with an option struct. The critical edge splitting API has a really large surface of flags and so it seems worth burning a small option struct / builder. This struct can be constructed with the various preserved analyses and then flags can be flipped in a builder style. The various users are now responsible for directly passing along their analysis information. This should be enough for the critical edge splitting to work cleanly with the new pass manager as well. This API is still pretty crufty and could be cleaned up a lot, but I've focused on this change just threading an option struct rather than a pass through the API. llvm-svn: 226456
* [PM] Replace another Pass argument with specific analyses that areChandler Carruth2015-01-181-1/+1
| | | | | | | | | optionally updated by MergeBlockIntoPredecessors. No functionality changed, just refactoring to clear the way for the new pass manager. llvm-svn: 226392
* [PM] Refactor how the LoopRotation pass access the DominatorTree.Chandler Carruth2015-01-181-20/+18
| | | | | | | | Instead of querying the pass every where we need to, do that once and cache a pointer in the pass object. This is both simpler and I'm about to add yet another place where we need to dig out that pointer. llvm-svn: 226391
* [PM] Split the LoopInfo object apart from the legacy pass, creatingChandler Carruth2015-01-171-4/+4
| | | | | | | | | | a LoopInfoWrapperPass to wire the object up to the legacy pass manager. This switches all the clients of LoopInfo over and paves the way to port LoopInfo to the new pass manager. No functionality change is intended with this iteration. llvm-svn: 226373
* [PM] Split the AssumptionTracker immutable pass into two separate APIs:Chandler Carruth2015-01-041-7/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | a cache of assumptions for a single function, and an immutable pass that manages those caches. The motivation for this change is two fold. Immutable analyses are really hacks around the current pass manager design and don't exist in the new design. This is usually OK, but it requires that the core logic of an immutable pass be reasonably partitioned off from the pass logic. This change does precisely that. As a consequence it also paves the way for the *many* utility functions that deal in the assumptions to live in both pass manager worlds by creating an separate non-pass object with its own independent API that they all rely on. Now, the only bits of the system that deal with the actual pass mechanics are those that actually need to deal with the pass mechanics. Once this separation is made, several simplifications become pretty obvious in the assumption cache itself. Rather than using a set and callback value handles, it can just be a vector of weak value handles. The callers can easily skip the handles that are null, and eventually we can wrap all of this up behind a filter iterator. For now, this adds boiler plate to the various passes, but this kind of boiler plate will end up making it possible to port these passes to the new pass manager, and so it will end up factored away pretty reasonably. llvm-svn: 225131
* Do not simplifyLatch for loops where hoisting increments couldresult in ↵Yi Jiang2014-10-291-3/+30
| | | | | | extra live range interferance llvm-svn: 220872
* Make use of @llvm.assume in ValueTracking (computeKnownBits, etc.)Hal Finkel2014-09-071-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This change, which allows @llvm.assume to be used from within computeKnownBits (and other associated functions in ValueTracking), adds some (optional) parameters to computeKnownBits and friends. These functions now (optionally) take a "context" instruction pointer, an AssumptionTracker pointer, and also a DomTree pointer, and most of the changes are just to pass this new information when it is easily available from InstSimplify, InstCombine, etc. As explained below, the significant conceptual change is that known properties of a value might depend on the control-flow location of the use (because we care that the @llvm.assume dominates the use because assumptions have control-flow dependencies). This means that, when we ask if bits are known in a value, we might get different answers for different uses. The significant changes are all in ValueTracking. Two main changes: First, as with the rest of the code, new parameters need to be passed around. To make this easier, I grouped them into a structure, and I made internal static versions of the relevant functions that take this structure as a parameter. The new code does as you might expect, it looks for @llvm.assume calls that make use of the value we're trying to learn something about (often indirectly), attempts to pattern match that expression, and uses the result if successful. By making use of the AssumptionTracker, the process of finding @llvm.assume calls is not expensive. Part of the structure being passed around inside ValueTracking is a set of already-considered @llvm.assume calls. This is to prevent a query using, for example, the assume(a == b), to recurse on itself. The context and DT params are used to find applicable assumptions. An assumption needs to dominate the context instruction, or come after it deterministically. In this latter case we only handle the specific case where both the assumption and the context instruction are in the same block, and we need to exclude assumptions from being used to simplify their own ephemeral values (those which contribute only to the assumption) because otherwise the assumption would prove its feeding comparison trivial and would be removed. This commit adds the plumbing and the logic for a simple masked-bit propagation (just enough to write a regression test). Future commits add more patterns (and, correspondingly, more regression tests). llvm-svn: 217342
* Add functions for finding ephemeral valuesHal Finkel2014-09-071-1/+9
| | | | | | | | | | | | | | | | This adds a set of utility functions for collecting 'ephemeral' values. These are LLVM IR values that are used only by @llvm.assume intrinsics (directly or indirectly), and thus will be removed prior to code generation, implying that they should be considered free for certain purposes (like inlining). The inliner's cost analysis, and a few other passes, have been updated to account for ephemeral values using the provided functionality. This functionality is important for the usability of @llvm.assume, because it limits the "non-local" side-effects of adding llvm.assume on inlining, loop unrolling, etc. (these are hints, and do not generate code, so they should not directly contribute to estimates of execution cost). llvm-svn: 217335
* Fix typos in comments and docJF Bastien2014-08-051-2/+2
| | | | | | Committing http://reviews.llvm.org/D4798 for Robin Morisset (morisset@google.com) llvm-svn: 214934
* Make the LoopRotate pass's maximum header size configurable both ↵Owen Anderson2014-05-261-4/+14
| | | | | | | | | | programmatically and via the command line, mirroring similar functionality in LoopUnroll. In situations where clients used custom unrolling thresholds, their intent could previously be foiled by LoopRotate having a hardcoded threshold. llvm-svn: 209617
* [C++] Use 'nullptr'. Transforms edition.Craig Topper2014-04-251-3/+3
| | | | llvm-svn: 207196
* [Modules] Fix potential ODR violations by sinking the DEBUG_TYPEChandler Carruth2014-04-221-1/+2
| | | | | | | | | | | | | | | | | definition below all of the header #include lines, lib/Transforms/... edition. This one is tricky for two reasons. We again have a couple of passes that define something else before the includes as well. I've sunk their name macros with the DEBUG_TYPE. Also, InstCombine contains headers that need DEBUG_TYPE, so now those headers #define and #undef DEBUG_TYPE around their code, leaving them well formed modular headers. Fixing these headers was a large motivation for all of these changes, as "leaky" macros of this form are hard on the modules implementation. llvm-svn: 206844
* D3348 - [BUG] "Rotate Loop" pass kills "llvm.vectorizer.enable" metadataAlexey Bataev2014-04-151-0/+9
| | | | llvm-svn: 206266
* [C++11] Add range based accessors for the Use-Def chain of a Value.Chandler Carruth2014-03-091-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This requires a number of steps. 1) Move value_use_iterator into the Value class as an implementation detail 2) Change it to actually be a *Use* iterator rather than a *User* iterator. 3) Add an adaptor which is a User iterator that always looks through the Use to the User. 4) Wrap these in Value::use_iterator and Value::user_iterator typedefs. 5) Add the range adaptors as Value::uses() and Value::users(). 6) Update *all* of the callers to correctly distinguish between whether they wanted a use_iterator (and to explicitly dig out the User when needed), or a user_iterator which makes the Use itself totally opaque. Because #6 requires churning essentially everything that walked the Use-Def chains, I went ahead and added all of the range adaptors and switched them to range-based loops where appropriate. Also because the renaming requires at least churning every line of code, it didn't make any sense to split these up into multiple commits -- all of which would touch all of the same lies of code. The result is still not quite optimal. The Value::use_iterator is a nice regular iterator, but Value::user_iterator is an iterator over User*s rather than over the User objects themselves. As a consequence, it fits a bit awkwardly into the range-based world and it has the weird extra-dereferencing 'operator->' that so many of our iterators have. I think this could be fixed by providing something which transforms a range of T&s into a range of T*s, but that *can* be separated into another patch, and it isn't yet 100% clear whether this is the right move. However, this change gets us most of the benefit and cleans up a substantial amount of code around Use and User. =] llvm-svn: 203364
* [C++11] Add 'override' keyword to virtual methods that override their base ↵Craig Topper2014-03-051-2/+2
| | | | | | class. llvm-svn: 202953
* [Modules] Move CFG.h to the IR library as it defines graph traits overChandler Carruth2014-03-041-1/+1
| | | | | | IR types. llvm-svn: 202827
* Disable most IR-level transform passes on functions marked 'optnone'.Paul Robinson2014-02-061-0/+3
| | | | | | | | | Ideally only those transform passes that run at -O0 remain enabled, in reality we get as close as we reasonably can. Passes are responsible for disabling themselves, it's not the job of the pass manager to do it for them. llvm-svn: 200892
* [LPM] Fix PR18643, another scary place where loop transforms failed toChandler Carruth2014-01-291-3/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | preserve loop simplify of enclosing loops. The problem here starts with LoopRotation which ends up cloning code out of the latch into the new preheader it is buidling. This can create a new edge from the preheader into the exit block of the loop which breaks LoopSimplify form. The code tries to fix this by splitting the critical edge between the latch and the exit block to get a new exit block that only the latch dominates. This sadly isn't sufficient. The exit block may be an exit block for multiple nested loops. When we clone an edge from the latch of the inner loop to the new preheader being built in the outer loop, we create an exiting edge from the outer loop to this exit block. Despite breaking the LoopSimplify form for the inner loop, this is fine for the outer loop. However, when we split the edge from the inner loop to the exit block, we create a new block which is in neither the inner nor outer loop as the new exit block. This is a predecessor to the old exit block, and so the split itself takes the outer loop out of LoopSimplify form. We need to split every edge entering the exit block from inside a loop nested more deeply than the exit block in order to preserve all of the loop simplify constraints. Once we try to do that, a problem with splitting critical edges surfaces. Previously, we tried a very brute force to update LoopSimplify form by re-computing it for all exit blocks. We don't need to do this, and doing this much will sometimes but not always overlap with the LoopRotate bug fix. Instead, the code needs to specifically handle the cases which can start to violate LoopSimplify -- they aren't that common. We need to see if the destination of the split edge was a loop exit block in simplified form for the loop of the source of the edge. For this to be true, all the predecessors need to be in the exact same loop as the source of the edge being split. If the dest block was originally in this form, we have to split all of the deges back into this loop to recover it. The old mechanism of doing this was conservatively correct because at least *one* of the exiting blocks it rewrote was the DestBB and so the DestBB's predecessors were fixed. But this is a much more targeted way of doing it. Making it targeted is important, because ballooning the set of edges touched prevents LoopRotate from being able to split edges *it* needs to split to preserve loop simplify in a coherent way -- the critical edge splitting would sometimes find the other edges in need of splitting but not others. Many, *many* thanks for help from Nick reducing these test cases mightily. And helping lots with the analysis here as this one was quite tricky to track down. llvm-svn: 200393
* [PM] Split DominatorTree into a concrete analysis result object whichChandler Carruth2014-01-131-16/+21
| | | | | | | | | | | | | | | | | | | | | | | can be used by both the new pass manager and the old. This removes it from any of the virtual mess of the pass interfaces and lets it derive cleanly from the DominatorTreeBase<> template. In turn, tons of boilerplate interface can be nuked and it turns into a very straightforward extension of the base DominatorTree interface. The old analysis pass is now a simple wrapper. The names and style of this split should match the split between CallGraph and CallGraphWrapperPass. All of the users of DominatorTree have been updated to match using many of the same tricks as with CallGraph. The goal is that the common type remains the resulting DominatorTree rather than the pass. This will make subsequent work toward the new pass manager significantly easier. Also in numerous places things became cleaner because I switched from re-running the pass (!!! mid way through some other passes run!!!) to directly recomputing the domtree. llvm-svn: 199104
* [cleanup] Move the Dominators.h and Verifier.h headers into the IRChandler Carruth2014-01-131-1/+1
| | | | | | | | | | | | | | | | | | directory. These passes are already defined in the IR library, and it doesn't make any sense to have the headers in Analysis. Long term, I think there is going to be a much better way to divide these matters. The dominators code should be fully separated into the abstract graph algorithm and have that put in Support where it becomes obvious that evn Clang's CFGBlock's can use it. Then the verifier can manually construct dominance information from the Support-driven interface while the Analysis library can provide a pass which both caches, reconstructs, and supports a nice update API. But those are very long term, and so I don't want to leave the really confusing structure until that day arrives. llvm-svn: 199082
* Don't #include heavy Dominators.h file in LoopInfo.h. This change reducesJakub Staszak2013-12-071-0/+1
| | | | | | overall time of LLVM compilation by ~1%. llvm-svn: 196667
* Correct word hyphenationsAlp Toker2013-12-051-1/+1
| | | | | | | This patch tries to avoid unrelated changes other than fixing a few hyphen-related ambiguities and contractions in nearby lines. llvm-svn: 196471
* Rotate multi-exit loops even if the latch was simplified.Andrew Trick2013-05-061-14/+29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Test case by Michele Scandale! Fixes PR10293: Load not hoisted out of loop with multiple exits. There are few regressions with this patch, now tracked by rdar:13817079, and a roughly equal number of improvements. The regressions are almost certainly back luck because LoopRotate has very little idea of whether rotation is profitable. Doing better requires a more comprehensive solution. This checkin is a quick fix that lacks generality (PR10293 has a counter-example). But it trivially fixes the case in PR10293 without interfering with other cases, and it does satify the criteria that LoopRotate is a loop canonicalization pass that should avoid heuristics and special cases. I can think of two approaches that would probably be better in the long run. Ultimately they may both make sense. (1) LoopRotate should check that the current header would make a good loop guard, and that the loop does not already has a sufficient guard. The artifical SimplifiedLoopLatch check would be unnecessary, and the design would be more general and canonical. Two difficulties: - We need a strong guarantee that we won't endlessly rotate, so the analysis would need to be precise in order to avoid the SimplifiedLoopLatch precondition. - Analysis like this are usually based on SCEV, which we don't want to rely on. (2) Rotate on-demand in late loop passes. This could even be done by shoving the loop back on the queue after the optimization that needs it. This could work well when we find LICM opportunities in multi-branch loops. This requires some work, and it doesn't really solve the problem of SCEV wanting a loop guard before the analysis. llvm-svn: 181230
* Switch CodeMetrics itself over to use TTI to determine if an instructionChandler Carruth2013-01-211-1/+6
| | | | | | | | | | | | is free. The whole CodeMetrics API should probably be reworked more, but this is enough to allow deleting the duplicate code there for computing whether an instruction is free. All of the passes using this have been updated to pull in TTI and hand it to the CodeMetrics stuff. Further, a dead CodeMetrics API (analyzeFunction) is nuked for lack of users. llvm-svn: 173036
* Move all of the header files which are involved in modelling the LLVM IRChandler Carruth2013-01-021-2/+2
| | | | | | | | | | | | | | | | | | | | | into their new header subdirectory: include/llvm/IR. This matches the directory structure of lib, and begins to correct a long standing point of file layout clutter in LLVM. There are still more header files to move here, but I wanted to handle them in separate commits to make tracking what files make sense at each layer easier. The only really questionable files here are the target intrinsic tablegen files. But that's a battle I'd rather not fight today. I've updated both CMake and Makefile build systems (I think, and my tests think, but I may have missed something). I've also re-sorted the includes throughout the project. I'll be committing updates to Clang, DragonEgg, and Polly momentarily. llvm-svn: 171366
* Add a new attribute, 'noduplicate'. If a function contains a noduplicate ↵James Molloy2012-12-201-1/+7
| | | | | | | | call, the call cannot be duplicated - Jump threading, loop unrolling, loop unswitching, and loop rotation are inhibited if they would duplicate the call. Similarly inlining of the function is inhibited, if that would duplicate the call (in particular inlining is still allowed when there is only one callsite and the function has internal linkage). llvm-svn: 170704
* Use the new script to sort the includes of every file under lib.Chandler Carruth2012-12-031-7/+7
| | | | | | | | | | | | | | | | | Sooooo many of these had incorrect or strange main module includes. I have manually inspected all of these, and fixed the main module include to be the nearest plausible thing I could find. If you own or care about any of these source files, I encourage you to take some time and check that these edits were sensible. I can't have broken anything (I strictly added headers, and reordered them, never removed), but they may not be the headers you'd really like to identify as containing the API being implemented. Many forward declarations and missing includes were added to a header files to allow them to parse cleanly when included first. The main module rule does in fact have its merits. =] llvm-svn: 169131
* LoopRotation: Make the brute force DomTree update more brute force.Benjamin Kramer2012-09-021-32/+21
| | | | | | | | | | | | | | We update until we hit a fixpoint. This is probably slow but also slightly simplifies the code. It should also fix the occasional invalid domtrees observed when building with expensive checking. I couldn't find a case where this had a measurable slowdown, but if someone finds a pathological case where it does we may have to find a cleverer way of updating dominators here. Thanks to Duncan for the test case. llvm-svn: 163091
* LoopRotation: Check some invariants of the dominator updating code.Benjamin Kramer2012-09-011-0/+3
| | | | llvm-svn: 163058
* LoopRotate: Also rotate loops with multiple exits.Benjamin Kramer2012-08-301-13/+60
| | | | | | | | | | | | | | | The old PHI updating code in loop-rotate was replaced with SSAUpdater a while ago, it has no problems with comples PHIs. What had to be fixed is detecting whether a loop was already rotated and updating dominators when multiple exits were present. This change increases overall code size a bit, mostly due to additional loop unrolling opportunities. Passes test-suite and selfhost with -verify-dom-info. Fixes PR7447. Thanks to Andy for the input on the domtree updating code. llvm-svn: 162912
* Clean whitespaces.Nadav Rotem2012-07-241-3/+4
| | | | llvm-svn: 160668
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