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* [PM] Port TailCallElimSean Silva2016-07-061-2/+19
| | | | llvm-svn: 274708
* Apply clang-tidy's modernize-loop-convert to most of lib/Transforms.Benjamin Kramer2016-06-261-4/+4
| | | | | | Only minor manual fixes. No functionality change intended. llvm-svn: 273808
* [TailRecursionElimination] Refactor/cleanup.Davide Italiano2016-06-021-150/+121
| | | | | | | | | In preparation for porting to the new PM. Patch by Jake VanAdrighem! (review mainly by me/Justin) Differential Revision: http://reviews.llvm.org/D20610 llvm-svn: 271607
* isSafeToLoadUnconditionally support queries without a contextArtur Pilipenko2016-04-271-1/+2
| | | | | | | | | | This is required to use this function from isSafeToSpeculativelyExecute Reviewed By: hfinkel Differential Revision: http://reviews.llvm.org/D16231 llvm-svn: 267692
* Re-commit optimization bisect support (r267022) without new pass manager ↵Andrew Kaylor2016-04-221-1/+1
| | | | | | | | | | support. The original commit was reverted because of a buildbot problem with LazyCallGraph::SCC handling (not related to the OptBisect handling). Differential Revision: http://reviews.llvm.org/D19172 llvm-svn: 267231
* Revert "Initial implementation of optimization bisect support."Vedant Kumar2016-04-221-1/+1
| | | | | | | | This reverts commit r267022, due to an ASan failure: http://lab.llvm.org:8080/green/job/clang-stage2-cmake-RgSan_check/1549 llvm-svn: 267115
* Initial implementation of optimization bisect support.Andrew Kaylor2016-04-211-1/+1
| | | | | | | | | | | | This patch implements a optimization bisect feature, which will allow optimizations to be selectively disabled at compile time in order to track down test failures that are caused by incorrect optimizations. The bisection is enabled using a new command line option (-opt-bisect-limit). Individual passes that may be skipped call the OptBisect object (via an LLVMContext) to see if they should be skipped based on the bisect limit. A finer level of control (disabling individual transformations) can be managed through an addition OptBisect method, but this is not yet used. The skip checking in this implementation is based on (and replaces) the skipOptnoneFunction check. Where that check was being called, a new call has been inserted in its place which checks the bisect limit and the optnone attribute. A new function call has been added for module and SCC passes that behaves in a similar way. Differential Revision: http://reviews.llvm.org/D19172 llvm-svn: 267022
* Change isSafeToLoadUnconditionally arguments order. Separated from ↵Artur Pilipenko2016-01-151-2/+2
| | | | | | http://reviews.llvm.org/D10920. llvm-svn: 257894
* [TRE] Simplify code with range-based loops and std::find.Benjamin Kramer2016-01-091-7/+2
| | | | | | No functional change intended. llvm-svn: 257261
* [OperandBundles] Have TailCallElim play nice with operand bundlesDavid Majnemer2015-12-231-2/+2
| | | | | | | | | A call site's use of a Value might not correspond to an argument operand but to a bundle operand. This fixes PR25928. llvm-svn: 256328
* Add 'notail' marker for call instructions.Akira Hatanaka2015-11-061-2/+4
| | | | | | | | | | | | This marker prevents optimization passes from adding 'tail' or 'musttail' markers to a call. Is is used to prevent tail call optimization from being performed on the call. rdar://problem/22667622 Differential Revision: http://reviews.llvm.org/D12923 llvm-svn: 252368
* Scalar: Remove remaining ilist iterator implicit conversionsDuncan P. N. Exon Smith2015-10-131-16/+14
| | | | | | | | | | | | | | | | | | | 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
* Add GlobalsAA as preserved to a bunch of transformsJames Molloy2015-09-101-0/+2
| | | | | | GlobalsAA must by definition be preserved in function passes, but the passmanager doesn't know that. Make each pass explicitly preserve GlobalsAA. llvm-svn: 247263
* Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC)Alexander Kornienko2015-06-231-2/+2
| | | | | | Apparently, the style needs to be agreed upon first. llvm-svn: 240390
* Fixed/added namespace ending comments using clang-tidy. NFCAlexander Kornienko2015-06-191-2/+2
| | | | | | | | | | | | | 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
* Remove DisableTailCalls from TargetOptions and the code in resetTargetOptionsAkira Hatanaka2015-06-091-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | that was resetting it. Remove the uses of DisableTailCalls in subclasses of TargetLowering and use the value of function attribute "disable-tail-calls" instead. Also, unconditionally add pass TailCallElim to the pipeline and check the function attribute at the start of runOnFunction to disable the pass on a per-function basis. This is part of the work to remove TargetMachine::resetTargetOptions, and since DisableTailCalls was the last non-fast-math option that was being reset in that function, we should be able to remove the function entirely after the work to propagate IR-level fast-math flags to DAG nodes is completed. Out-of-tree users should remove the uses of DisableTailCalls and make changes to attach attribute "disable-tail-calls"="true" or "false" to the functions in the IR. rdar://problem/13752163 Differential Revision: http://reviews.llvm.org/D10099 llvm-svn: 239427
* Re-sort includes with sort-includes.py and insert raw_ostream.h where it's used.Benjamin Kramer2015-03-231-1/+1
| | | | llvm-svn: 232998
* DataLayout is mandatory, update the API to reflect it with references.Mehdi Amini2015-03-101-5/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
* Make DataLayout Non-Optional in the ModuleMehdi Amini2015-03-041-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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> llvm-svn: 231270
* TRE: Just erase dead BBs and tweak the iteration loop not to increment the ↵Benjamin Kramer2015-02-281-19/+7
| | | | | | | | | | | deleted BB iterator. Leaving empty blocks around just opens up a can of bugs like PR22704. Deleting them early also slightly simplifies code. Thanks to Sanjay for the IR test case. llvm-svn: 230856
* remove function names from comments; NFCSanjay Patel2015-02-271-20/+15
| | | | llvm-svn: 230766
* [multiversion] Thread a function argument through all the callers of theChandler Carruth2015-02-011-1/+1
| | | | | | | | | | | | | | 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
* Fix tail recursion eliminationArnaud A. de Grandmaison2014-11-191-3/+25
| | | | | | | | | | | | | | | | | | | | | | When the BasicBlock containing the return instrution has a PHI with 2 incoming values, FoldReturnIntoUncondBranch will remove the no longer used incoming value and remove the no longer needed phi as well. This leaves us with a BB that no longer has a PHI, but the subsequent call to FoldReturnIntoUncondBranch from FoldReturnAndProcessPred will not remove the return instruction (which still uses the result of the call instruction). This prevents EliminateRecursiveTailCall to remove the value, as it is still being used in a basicblock which has no predecessors. The basicblock can not be erased on the spot, because its iterator is still being used in runTRE. This issue was exposed when removing the threshold on size for lifetime marker insertion for named temporaries in clang. The testcase is a much reduced version of peelOffOuterExpr(const Expr*, const ExplodedNode *) from clang/lib/StaticAnalyzer/Core/BugReporterVisitors.cpp. llvm-svn: 222354
* Update SetVector to rely on the underlying set's insert to return a ↵David Blaikie2014-11-191-1/+1
| | | | | | | | | | | | | pair<iterator, bool> This is to be consistent with StringSet and ultimately with the standard library's associative container insert function. This lead to updating SmallSet::insert to return pair<iterator, bool>, and then to update SmallPtrSet::insert to return pair<iterator, bool>, and then to update all the existing users of those functions... llvm-svn: 222334
* Revert "Transforms: reapply SVN r219899"Reid Kleckner2014-11-041-2/+8
| | | | | | | This reverts commit r220811 and r220839. It made an incorrect change to musttail handling. llvm-svn: 221226
* Transforms: reapply SVN r219899Saleem Abdulrasool2014-10-281-8/+2
| | | | | | | | | | | | | | | | This restores the commit from SVN r219899 with an additional change to ensure that the CodeGen is correct for the case that was identified as being incorrect (originally PR7272). In the case that during inlining we need to synthesize a value on the stack (i.e. for passing a value byval), then any function involving that alloca must be stripped of its tailness as the restriction that it does not access the parent's stack no longer holds. Unfortunately, a single alloca can cause a rippling effect through out the inlining as the value may be aliased or may be mutated through an escaped external call. As such, we simply track if an alloca has been introduced in the frame during inlining, and strip any tail calls. llvm-svn: 220811
* Fix a long-standing miscompile in the load analysis that was uncoveredChandler Carruth2014-10-191-1/+5
| | | | | | | | | | | | | | | | | | | by my refactoring of this code. The method isSafeToLoadUnconditionally assumes that the load will proceed with the preferred type alignment. Given that, it has to ensure that the alloca or global is at least that aligned. It has always done this historically when a datalayout is present, but has never checked it when the datalayout is absent. When I refactored the code in r220156, I exposed this path when datalayout was present and that turned the latent bug into a patent bug. This fixes the issue by just removing the special case which allows folding things without datalayout. This isn't worth the complexity of trying to tease apart when it is or isn't safe without actually knowing the preferred alignment. llvm-svn: 220161
* Revert "TRE: make TRE a bit more aggressive"Rafael Espindola2014-10-171-2/+8
| | | | | | | | | This reverts commit r219899. This also updates byval-tail-call.ll to make it clear what was breaking. Adding r219899 again will cause the load/store to disappear. llvm-svn: 220093
* TRE: make TRE a bit more aggressiveSaleem Abdulrasool2014-10-161-8/+2
| | | | | | | | | Make tail recursion elimination a bit more aggressive. This allows us to get tail recursion on functions that are just branches to a different function. The fact that the function takes a byval argument does not restrict it from being optimised into just a tail call. llvm-svn: 219899
* We may visit a call that uses an alloca multiple times in ↵Nick Lewycky2014-07-231-5/+3
| | | | | | callUsesLocalStack, sometimes with IsNocapture true and sometimes with IsNocapture false. We accidentally skipped work we needed to do in the IsNocapture=false case if we were called with IsNocapture=true the first time. Fixes PR20405! llvm-svn: 213726
* Revert "[C++11] Add predecessors(BasicBlock *) / successors(BasicBlock *) ↵Duncan P. N. Exon Smith2014-07-211-2/+3
| | | | | | | | | iterator ranges." This reverts commit r213474 (and r213475), which causes a miscompile on a stage2 LTO build. I'll reply on the list in a moment. llvm-svn: 213562
* [C++11] Add predecessors(BasicBlock *) / successors(BasicBlock *) iterator ↵Manuel Jacob2014-07-201-3/+2
| | | | | | | | | | | | | | | | | | ranges. Summary: This patch introduces two new iterator ranges and updates existing code to use it. No functional change intended. Test Plan: All tests (make check-all) still pass. Reviewers: dblaikie Reviewed By: dblaikie Subscribers: llvm-commits Differential Revision: http://reviews.llvm.org/D4481 llvm-svn: 213474
* Add support for missed and analysis optimization remarks.Diego Novillo2014-05-221-8/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: This adds two new diagnostics: -pass-remarks-missed and -pass-remarks-analysis. They take the same values as -pass-remarks but are intended to be triggered in different contexts. -pass-remarks-missed is used by LLVMContext::emitOptimizationRemarkMissed, which passes call when they tried to apply a transformation but couldn't. -pass-remarks-analysis is used by LLVMContext::emitOptimizationRemarkAnalysis, which passes call when they want to inform the user about analysis results. The patch also: 1- Adds support in the inliner for the two new remarks and a test case. 2- Moves emitOptimizationRemark* functions to the llvm namespace. 3- Adds an LLVMContext argument instead of making them member functions of LLVMContext. Reviewers: qcolombet Subscribers: llvm-commits Differential Revision: http://reviews.llvm.org/D3682 llvm-svn: 209442
* Improve wording to make it sounds more like a change than an analysis.Nick Lewycky2014-05-081-2/+3
| | | | llvm-svn: 208370
* Simplify and fix incorrect comment. No functionality change.Richard Smith2014-05-081-22/+15
| | | | llvm-svn: 208272
* Detabify.Nick Lewycky2014-05-061-2/+2
| | | | llvm-svn: 208019
* Improve 'tail' call marking in TRE. A bootstrap of clang goes from 375k ↵Nick Lewycky2014-05-051-73/+241
| | | | | | | | | | calls marked tail in the IR to 470k, however this improvement does not carry into an improvement of the call/jmp ratio on x86. The most common pattern is a tail call + br to a block with nothing but a 'ret'. The number of tail call to loop conversions remains the same (1618 by my count). The new algorithm does a local scan over the use-def chains to identify local "alloca-derived" values, as well as points where the alloca could escape. Then, a visit over the CFG marks blocks as being before or after the allocas have escaped, and annotates the calls accordingly. llvm-svn: 208017
* [C++] Use 'nullptr'. Transforms edition.Craig Topper2014-04-251-18/+18
| | | | 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
* Fix PR7272 in -tailcallelim instead of the inlinerReid Kleckner2014-04-211-0/+9
| | | | | | | | | | | | | | | | The -tailcallelim pass should be checking if byval or inalloca args can be captured before marking calls as tail calls. This was the real root cause of PR7272. With a better fix in place, revert the inliner change from r105255. The test case it introduced still passes and has been moved to test/Transforms/Inline/byval-tail-call.ll. Reviewers: chandlerc Differential Revision: http://reviews.llvm.org/D3403 llvm-svn: 206789
* [C++11] Add range based accessors for the Use-Def chain of a Value.Chandler Carruth2014-03-091-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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] Make this interface accept const Use pointers and use overrideChandler Carruth2014-03-051-2/+2
| | | | | | | | to ensure we don't mess up any of the overrides. Necessary for cleaning up the Value use iterators and enabling range-based traversing of use lists. llvm-svn: 202958
* [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
* [Modules] Move ValueHandle into the IR library where Value itself lives.Chandler Carruth2014-03-041-1/+1
| | | | | | | | | | | Move the test for this class into the IR unittests as well. This uncovers that ValueMap too is in the IR library. Ironically, the unittest for ValueMap is useless in the Support library (honestly, so was the ValueHandle test) and so it already lives in the IR unittests. Mmmm, tasty layering. llvm-svn: 202821
* [Modules] Move CallSite into the IR library where it belogs. It isChandler Carruth2014-03-041-1/+1
| | | | | | | abstracting between a CallInst and an InvokeInst, both of which are IR concepts. llvm-svn: 202816
* [C++11] Replace llvm::next and llvm::prior with std::next and std::prev.Benjamin Kramer2014-03-021-1/+1
| | | | | | Remove the old functions. llvm-svn: 202636
* Switch all uses of LLVM_OVERRIDE to just use 'override' directly.Craig Topper2014-03-021-3/+3
| | | | llvm-svn: 202621
* 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
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