[SCEV] Add and use SCEVConstant::getAPInt; NFCI git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@255921 91177308-0d34-0410-b5e6-96231b3b80d8
LPM: Stop threading `Pass *` through all of the loop utility APIs. NFC A large number of loop utility functions take a `Pass *` and reach into it to find out which analyses to preserve. There are a number of problems with this: - The APIs have access to pretty well any Pass state they want, so it's hard to tell what they may or may not do. - Other APIs have copied these and pass around a `Pass *` even though they don't even use it. Some of these just hand a nullptr to the API since the callers don't even have a pass available. - Passes in the new pass manager don't work like the current ones, so the APIs can't be used as is there. Instead, we should explicitly thread the analysis results that we actually care about through these APIs. This is both simpler and more reusable. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@255669 91177308-0d34-0410-b5e6-96231b3b80d8
[ScalarOpts] Remove dead code. Does not touch debug dumpers. NFC. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@250417 91177308-0d34-0410-b5e6-96231b3b80d8
Scalar: Remove remaining ilist iterator implicit conversions 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. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@250211 91177308-0d34-0410-b5e6-96231b3b80d8
[LoopReroll] Ignore debug intrinsics Originally, debug intrinsics and annotation intrinsics may prevent the loop to be rerolled, now they are ignored. Differential Revision: http://reviews.llvm.org/D13150 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@248718 91177308-0d34-0410-b5e6-96231b3b80d8
[SCEV] Introduce ScalarEvolution::getOne and getZero. Summary: It is fairly common to call SE->getConstant(Ty, 0) or SE->getConstant(Ty, 1); this change makes such uses a little bit briefer. I've refactored the call sites I could find easily to use getZero / getOne. Reviewers: hfinkel, majnemer, reames Subscribers: sanjoy, llvm-commits Differential Revision: http://reviews.llvm.org/D12947 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@248362 91177308-0d34-0410-b5e6-96231b3b80d8
[PM/AA] Rebuild LLVM's alias analysis infrastructure in a way compatible 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 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@247167 91177308-0d34-0410-b5e6-96231b3b80d8
[PM] Port ScalarEvolution to the new pass manager. 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 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@245193 91177308-0d34-0410-b5e6-96231b3b80d8
Handle loop with negtive induction variable increment This patch extend LoopReroll pass to hand the loops which is similar to the following: while (len > 1) { sum4 += buf[len]; sum4 += buf[len-1]; len -= 2; } git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243171 91177308-0d34-0410-b5e6-96231b3b80d8
Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC) Apparently, the style needs to be agreed upon first. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240390 91177308-0d34-0410-b5e6-96231b3b80d8
Fixed/added namespace ending comments using clang-tidy. NFC 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! git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240137 91177308-0d34-0410-b5e6-96231b3b80d8
Re-sort includes with sort-includes.py and insert raw_ostream.h where it's used. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@232998 91177308-0d34-0410-b5e6-96231b3b80d8
DataLayout is mandatory, update the API to reflect it with references. 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> git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@231740 91177308-0d34-0410-b5e6-96231b3b80d8
Make DataLayout Non-Optional in the Module Summary: DataLayout keeps the string used for its creation. As a side effect it is no longer needed in the Module. This is "almost" NFC, the string is no longer canonicalized, you can't rely on two "equals" DataLayout having the same string returned by getStringRepresentation(). Get rid of DataLayoutPass: the DataLayout is in the Module The DataLayout is "per-module", let's enforce this by not duplicating it more than necessary. One more step toward non-optionality of the DataLayout in the module. Make DataLayout Non-Optional in the Module Module->getDataLayout() will never returns nullptr anymore. Reviewers: echristo Subscribers: resistor, llvm-commits, jholewinski Differential Revision: http://reviews.llvm.org/D7992 From: Mehdi Amini <mehdi.amini@apple.com> git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@231270 91177308-0d34-0410-b5e6-96231b3b80d8
[LoopReroll] Relax some assumptions a little. We won't find a root with index zero in any loop that we are able to reroll. However, we may find one in a non-rerollable loop, so bail gracefully instead of failing hard. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229406 91177308-0d34-0410-b5e6-96231b3b80d8
[LoopReroll] Don't crash on dead code If a PHI has no users, don't crash; bail gracefully. This shouldn't happen often, but we can make no guarantees that previous passes didn't leave dead code around. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229405 91177308-0d34-0410-b5e6-96231b3b80d8
[LoopRerolling] Be more forgiving with instruction order. We can't solve the full subgraph isomorphism problem. But we can allow obvious cases, where for example two instructions of different types are out of order. Due to them having different types/opcodes, there is no ambiguity. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228931 91177308-0d34-0410-b5e6-96231b3b80d8
[LoopReroll] Introduce the concept of DAGRootSets. A DAGRootSet models an induction variable being used in a rerollable loop. For example: x[i*3+0] = y1 x[i*3+1] = y2 x[i*3+2] = y3 Base instruction -> i*3 +---+----+ / | \ ST[y1] +1 +2 <-- Roots | | ST[y2] ST[y3] There may be multiple DAGRootSets, for example: x[i*2+0] = ... (1) x[i*2+1] = ... (1) x[i*2+4] = ... (2) x[i*2+5] = ... (2) x[(i+1234)*2+5678] = ... (3) x[(i+1234)*2+5679] = ... (3) This concept is similar to the "Scale" member used previously, but allows multiple independent sets of roots based off the same induction variable. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228821 91177308-0d34-0410-b5e6-96231b3b80d8
[LoopReroll] Alter the data structures used during reroll validation. The validation algorithm used an incremental approach, building each iteration's data structures temporarily, validating them, then adding them to a global set. This does not scale well to having multiple sets of Root nodes, as the set of instructions used in each iteration is the union over all the root nodes. Therefore, refactor the logic to create a single, simple container to which later logic then refers. This makes it simpler control-flow wise to make the creation of the container more complex with the addition of multiple root sets. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227499 91177308-0d34-0410-b5e6-96231b3b80d8
[LoopReroll] Refactor most of reroll() into a helper class reroll() was slightly monolithic and a pain to modify. Refactor a bunch of its state from local variables to member variables of a helper class, and do some trivial simplification while we're there. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227439 91177308-0d34-0410-b5e6-96231b3b80d8