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* [ValueTracking] add helper function for testing implied condition; NFCISanjay Patel2018-12-021-22/+11
| | | | | | | | We were duplicating code around the existing isImpliedCondition() that checks for a predecessor block/dominating condition, so make that a wrapper call. llvm-svn: 348088
* [DebugInfo] Give inlinable calls DILocs (PR39807)Jeremy Morse2018-11-281-8/+9
| | | | | | | | | | | | | | | | | | | | In PR39807 we incorrectly handle circumstances where calls are common'd from conditional blocks into the parent BB. Calls that can be inlined must always have DebugLocs, however we strip them during commoning, which the IR verifier asserts on. Fix this by using applyMergedLocation: it will perform the same DebugLoc stripping of conditional Locs, but will also generate an unknown location DebugLoc that satisfies the requirement for inlinable calls to always have locations. Some of the prior logic for selecting a DebugLoc is now likely redundant; I'll generate a follow-up to remove it (involves editing more regression tests). Differential Revision: https://reviews.llvm.org/D54997 llvm-svn: 347782
* [IR] Add hasNPredecessors, hasNPredecessorsOrMore to BasicBlockVedant Kumar2018-11-191-3/+3
| | | | | | | | | | | | | | | | | | | | | | | Add methods to BasicBlock which make it easier to efficiently check whether a block has N (or more) predecessors. This can be more efficient than using pred_size(), which is a linear time operation. We might consider adding similar methods for successors. I haven't done so in this patch because succ_size() is already O(1). With this patch applied, I measured a 0.065% compile-time reduction in user time for running `opt -O3` on the sqlite3 amalgamation (30 trials). The change in mergeStoreIntoSuccessor alone saves 45 million linked list iterations in a stage2 Release build of llc. See llvm.org/PR39702 for a harder but more general way of achieving similar results. Differential Revision: https://reviews.llvm.org/D54686 llvm-svn: 347256
* [DebugInfo][Dexter] Unreachable line stepped onto after SimplifyCFG.Carlos Alberto Enciso2018-11-091-0/+16
| | | | | | | | In SimplifyCFG when given a conditional branch that goes to BB1 and BB2, the hoisted common terminator instruction in the two blocks, caused debug line records associated with subsequent select instructions to become ambiguous. It causes the debugger to display unreachable source lines. Differential Revision: https://reviews.llvm.org/D53390 llvm-svn: 346481
* ADT/STLExtras: Introduce llvm::empty; NFCMatthias Braun2018-10-311-1/+1
| | | | | | | | This is modeled after C++17 std::empty(). Differential Revision: https://reviews.llvm.org/D53909 llvm-svn: 345679
* [DebugInfo][Dexter] Unreachable line stepped onto after SimplifyCFG.Carlos Alberto Enciso2018-10-251-18/+4
| | | | | | | | When SimplifyCFG changes the PHI node into a select instruction, the debug line records becomes ambiguous. It causes the debugger to display unreachable source lines. Differential Revision: https://reviews.llvm.org/D53287 llvm-svn: 345250
* [TI removal] Make variables declared as `TerminatorInst` and initializedChandler Carruth2018-10-151-40/+40
| | | | | | | | | | | | | by `getTerminator()` calls instead be declared as `Instruction`. This is the biggest remaining chunk of the usage of `getTerminator()` that insists on the narrow type and so is an easy batch of updates. Several files saw more extensive updates where this would cascade to requiring API updates within the file to use `Instruction` instead of `TerminatorInst`. All of these were trivial in nature (pervasively using `Instruction` instead just worked). llvm-svn: 344502
* Revert "[DebugInfo][Dexter] Unreachable line stepped onto after SimplifyCFG."Carlos Alberto Enciso2018-10-101-4/+18
| | | | | | | | This reverts commit r344120. It was causing buildbot failures. llvm-svn: 344135
* [DebugInfo][Dexter] Unreachable line stepped onto after SimplifyCFG.Carlos Alberto Enciso2018-10-101-18/+4
| | | | | | | | When SimplifyCFG changes the PHI node into a select instruction, the debug line records becomes ambiguous. It causes the debugger to display unreachable source lines. Differential Revision: https://reviews.llvm.org/D52887 llvm-svn: 344120
* [SimplifyCFG] Pass AggressiveInsts to DominatesMergePoint by reference. ↵Craig Topper2018-10-041-11/+6
| | | | | | | | | | | | | | | | | | | Remove null check. Summary: At some point in the past the recursion in DominatesMergePoint used to pass null for AggressiveInsts as part of the recursion. It no longer does this. So there is no way for AggressiveInsts to be null. This passes it by reference and removes the null check to make this explicit. Reviewers: efriedma, reames Reviewed By: efriedma Subscribers: xbolva00, llvm-commits Differential Revision: https://reviews.llvm.org/D52575 llvm-svn: 343828
* [SimplifyCFG] Change recursive calls to llvm::SimplifyCFG to instead use an ↵Craig Topper2018-10-041-29/+54
| | | | | | | | | | | | | | | | | | | outer while loop to revisit. Summary: The llvm::SimplifyCFG function creates a SimplifyCFGOpt object and calls run on it. There were numerous places reached from this run function that called back out llvm::SimplifyCFG which would create another SimplifyCFGOpt object. This is an inefficient use of stack space at minimum. We are also not passing along the LoopHeaders pointer passed into the outer llvm::SimplifyCFG call. So if its not null we lose it on the first recursion and get nullptr from there on. This patch adds an outer loop around the main BasicBlock simplifying code and adds a flag to the SimplifyCFGOpt class that can be set by to request another iteration. I don't think we can iterate based just on the change flag alone since some of the simplifications delete a basic block entirely leaving nothing to iterate on. Reviewers: bogner, eli.friedman, reames Reviewed By: reames Subscribers: llvm-commits Differential Revision: https://reviews.llvm.org/D52760 llvm-svn: 343816
* [SimplifyCFG] Use Value::hasNUses instead of 'getNumUses() =='. NFCICraig Topper2018-10-011-1/+1
| | | | | | getNumUses is linear in the number of uses. Since we're looking for a specific use count, we can use hasNUses which will stop as soon as it determines there are more than N uses instead of walking all of them. llvm-svn: 343550
* [SimplifyCFG] Update comments that refer to CondBB to say ThenBB instead. NFCCraig Topper2018-10-011-4/+4
| | | | | | There is no variable in this function named CondBB, but there is one named ThenBB and I believe the comments are all refering to it. llvm-svn: 343548
* llvm::sort(C.begin(), C.end(), ...) -> llvm::sort(C, ...)Fangrui Song2018-09-271-1/+1
| | | | | | | | | | | | Summary: The convenience wrapper in STLExtras is available since rL342102. Reviewers: dblaikie, javed.absar, JDevlieghere, andreadb Subscribers: MatzeB, sanjoy, arsenm, dschuff, mehdi_amini, sdardis, nemanjai, jvesely, nhaehnle, sbc100, jgravelle-google, eraman, aheejin, kbarton, JDevlieghere, javed.absar, gbedwell, jrtc27, mgrang, atanasyan, steven_wu, george.burgess.iv, dexonsmith, kristina, jsji, llvm-commits Differential Revision: https://reviews.llvm.org/D52573 llvm-svn: 343163
* [DebugInfo][Dexter] Speculated BB presents illegal variable value to debugger. Carlos Alberto Enciso2018-09-191-2/+6
| | | | | | | | When SimplifyCFG changes the PHI node into a select instruction, the debug information becomes ambiguous. It causes the debugger to display wrong variable value. Differential Revision: https://reviews.llvm.org/D51976 llvm-svn: 342527
* [SimplifyCFG] Put an alignment on generated switch tablesDavid Green2018-09-121-0/+3
| | | | | | | | | | Previously the alignment on the newly created switch table data was not set, meaning that DataLayout::getPreferredAlignment was free to overalign it to 16 bytes. This causes unnecessary code bloat. Differential Revision: https://reviews.llvm.org/D51800 llvm-svn: 342039
* Revert "[SimplifyCFG] Common debug handling [NFC]"Martin Storsjo2018-08-301-0/+8
| | | | | | | | | This reverts commit r340997. This change turned out not to be NFC after all, but e.g. causes clang to crash when building the linux kernel for aarch64. llvm-svn: 341031
* [SimplifyCFG] Rename a variable for readibility of a future change [NFC]Philip Reames2018-08-301-8/+9
| | | | llvm-svn: 341004
* [SimplifyCFG] Fix a cost modeling oversight in branch commoningPhilip Reames2018-08-301-2/+8
| | | | | | | | The cost modeling was not accounting for the fact we were duplicating the instruction once per predecessor. With a default threshold of 1, this meant we were actually creating #pred copies. Adding to the fun, there is *absolutely no* test coverage for this. Simply bailing for more than one predecessor passes all checked in tests. llvm-svn: 341001
* [SimplifyCFG] Common debug handling [NFC]Philip Reames2018-08-291-8/+0
| | | | llvm-svn: 340997
* [IR] Replace `isa<TerminatorInst>` with `isTerminator()`.Chandler Carruth2018-08-261-6/+4
| | | | | | | | | | | | This is a bit awkward in a handful of places where we didn't even have an instruction and now we have to see if we can build one. But on the whole, this seems like a win and at worst a reasonable cost for removing `TerminatorInst`. All of this is part of the removal of `TerminatorInst` from the `Instruction` type hierarchy. llvm-svn: 340701
* [IR] Sink `isExceptional` predicate to `Instruction`, rename it toChandler Carruth2018-08-261-1/+1
| | | | | | | | | | | `isExceptionalTermiantor` and implement it for opcodes as well following the common pattern in `Instruction`. Part of removing `TerminatorInst` from the `Instruction` type hierarchy to make it easier to share logic and interfaces between instructions that are both terminators and not terminators. llvm-svn: 340699
* [IR] Begin removal of TerminatorInst by removing successor manipulation.Chandler Carruth2018-08-261-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The core get and set routines move to the `Instruction` class. These routines are only valid to call on instructions which are terminators. The iterator and *generic* range based access move to `CFG.h` where all the other generic successor and predecessor access lives. While moving the iterator here, simplify it using the iterator utilities LLVM provides and updates coding style as much as reasonable. The APIs remain pointer-heavy when they could better use references, and retain the odd behavior of `operator*` and `operator->` that is common in LLVM iterators. Adjusting this API, if desired, should be a follow-up step. Non-generic range iteration is added for the two instructions where there is an especially easy mechanism and where there was code attempting to use the range accessor from a specific subclass: `indirectbr` and `br`. In both cases, the successors are contiguous operands and can be easily iterated via the operand list. This is the first major patch in removing the `TerminatorInst` type from the IR's instruction type hierarchy. This change was discussed in an RFC here and was pretty clearly positive: http://lists.llvm.org/pipermail/llvm-dev/2018-May/123407.html There will be a series of much more mechanical changes following this one to complete this move. Differential Revision: https://reviews.llvm.org/D47467 llvm-svn: 340698
* [Local] Make DoesKMove required for combineMetadata.Florian Hahn2018-08-241-2/+2
| | | | | | | | | | | | | | | This patch makes the DoesKMove argument non-optional, to force people to think about it. Most cases where it is false are either code hoisting or code sinking, where we pick one instruction from a set of equal instructions among different code paths. Reviewers: dberlin, nlopes, efriedma, davide Reviewed By: efriedma Differential Revision: https://reviews.llvm.org/D47475 llvm-svn: 340606
* [SimplifyCFG] Replace some uses of bitwise or with logical orJustin Bogner2018-08-201-25/+25
| | | | | | | It's clearer to use logical or for boolean values. Thanks to Steven Zhang for noticing! llvm-svn: 340153
* [SimplifyCFG] Remove pointer from SmallPtrSet before deletionChijun Sima2018-08-151-3/+3
| | | | | | | | | | | | | | | | | Summary: Previously, `eraseFromParent()` calls `delete` which invalidates the value of the pointer. Copying the value of the pointer later is undefined behavior in C++11 and implementation-defined (which may cause a segfault on implementations having strict pointer safety) in C++14. This patch removes the BasicBlock pointer from related SmallPtrSet before `delete` invalidates it in the SimplifyCFG pass. Reviewers: kuhar, dmgreen, davide, trentxintong Reviewed By: kuhar, dmgreen Subscribers: llvm-commits Differential Revision: https://reviews.llvm.org/D50717 llvm-svn: 339773
* llvm: Add support for "-fno-delete-null-pointer-checks"Manoj Gupta2018-07-091-3/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: Support for this option is needed for building Linux kernel. This is a very frequently requested feature by kernel developers. More details : https://lkml.org/lkml/2018/4/4/601 GCC option description for -fdelete-null-pointer-checks: This Assume that programs cannot safely dereference null pointers, and that no code or data element resides at address zero. -fno-delete-null-pointer-checks is the inverse of this implying that null pointer dereferencing is not undefined. This feature is implemented in LLVM IR in this CL as the function attribute "null-pointer-is-valid"="true" in IR (Under review at D47894). The CL updates several passes that assumed null pointer dereferencing is undefined to not optimize when the "null-pointer-is-valid"="true" attribute is present. Reviewers: t.p.northover, efriedma, jyknight, chandlerc, rnk, srhines, void, george.burgess.iv Reviewed By: efriedma, george.burgess.iv Subscribers: eraman, haicheng, george.burgess.iv, drinkcat, theraven, reames, sanjoy, xbolva00, llvm-commits Differential Revision: https://reviews.llvm.org/D47895 llvm-svn: 336613
* Comment change to verify commit rights. NFC.Jesper Antonsson2018-06-281-1/+1
| | | | | | | | | | Summary: Just a silly one-character correction. Subscribers: llvm-commits Differential Revision: https://reviews.llvm.org/D48709 llvm-svn: 335832
* Use SmallPtrSet explicitly for SmallSets with pointer types (NFC).Florian Hahn2018-06-121-1/+0
| | | | | | | | | | | | | | Currently SmallSet<PointerTy> inherits from SmallPtrSet<PointerTy>. This patch replaces such types with SmallPtrSet, because IMO it is slightly clearer and allows us to get rid of unnecessarily including SmallSet.h Reviewers: dblaikie, craig.topper Reviewed By: dblaikie Differential Revision: https://reviews.llvm.org/D47836 llvm-svn: 334492
* Use SmallPtrSet instead of SmallSet in places where we iterate over the set.Craig Topper2018-06-091-2/+2
| | | | | | | | SmallSet forwards to SmallPtrSet for pointer types. SmallPtrSet supports iteration, but a normal SmallSet doesn't. So if it wasn't for the forwarding, this wouldn't work. These places were found by hiding the begin/end methods in the SmallSet forwarding llvm-svn: 334343
* Move Analysis/Utils/Local.h back to TransformsDavid Blaikie2018-06-041-1/+1
| | | | | | | | | | Review feedback from r328165. Split out just the one function from the file that's used by Analysis. (As chandlerc pointed out, the original change only moved the header and not the implementation anyway - which was fine for the one function that was used (since it's a template/inlined in the header) but not in general) llvm-svn: 333954
* [SimplifyCFG] Fix a debug invariant bug in FoldBranchToCommonDest()David Stenberg2018-05-181-3/+5
| | | | | | | | | | | | | | | | | | | | | Summary: Fix a case where FoldBranchToCommonDest() would bail out from doing CSE when encountering a debug intrinsic. Handle that by skipping past the debug intrinsics. Also, as a minor refactoring, rename checkCSEInPredecessor() to tryCSEWithPredecessor() to make it a bit more clear that the function may remove instructions. Reviewers: fhahn, craig.topper, dblaikie, xbolva00 Reviewed By: fhahn, xbolva00 Subscribers: vsk, davide, llvm-commits Differential Revision: https://reviews.llvm.org/D46635 llvm-svn: 332698
* Rename DEBUG macro to LLVM_DEBUG.Nicola Zaghen2018-05-141-39/+43
| | | | | | | | | | | | | | | | The DEBUG() macro is very generic so it might clash with other projects. The renaming was done as follows: - git grep -l 'DEBUG' | xargs sed -i 's/\bDEBUG\s\?(/LLVM_DEBUG(/g' - git diff -U0 master | ../clang/tools/clang-format/clang-format-diff.py -i -p1 -style LLVM - Manual change to APInt - Manually chage DOCS as regex doesn't match it. In the transition period the DEBUG() macro is still present and aliased to the LLVM_DEBUG() one. Differential Revision: https://reviews.llvm.org/D43624 llvm-svn: 332240
* [STLExtras] Add distance() for ranges, pred_size(), and succ_size()Vedant Kumar2018-05-101-5/+3
| | | | | | | | | | | This commit adds a wrapper for std::distance() which works with ranges. As it would be a common case to write `distance(predecessors(BB))`, this also introduces `pred_size()` and `succ_size()` helpers to make that easier to write. Differential Revision: https://reviews.llvm.org/D46668 llvm-svn: 332057
* [DebugInfo] Add DILabel metadata and intrinsic llvm.dbg.label.Shiva Chen2018-05-091-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In order to set breakpoints on labels and list source code around labels, we need collect debug information for labels, i.e., label name, the function label belong, line number in the file, and the address label located. In order to keep these information in LLVM IR and to allow backend to generate debug information correctly. We create a new kind of metadata for labels, DILabel. The format of DILabel is !DILabel(scope: !1, name: "foo", file: !2, line: 3) We hope to keep debug information as much as possible even the code is optimized. So, we create a new kind of intrinsic for label metadata to avoid the metadata is eliminated with basic block. The intrinsic will keep existing if we keep it from optimized out. The format of the intrinsic is llvm.dbg.label(metadata !1) It has only one argument, that is the DILabel metadata. The intrinsic will follow the label immediately. Backend could get the label metadata through the intrinsic's parameter. We also create DIBuilder API for labels to be used by Frontend. Frontend could use createLabel() to allocate DILabel objects, and use insertLabel() to insert llvm.dbg.label intrinsic in LLVM IR. Differential Revision: https://reviews.llvm.org/D45024 Patch by Hsiangkai Wang. llvm-svn: 331841
* Range-ify for loop; NFCGeorge Burgess IV2018-05-051-2/+1
| | | | llvm-svn: 331582
* Remove \brief commands from doxygen comments.Adrian Prantl2018-05-011-2/+2
| | | | | | | | | | | | | | | | We've been running doxygen with the autobrief option for a couple of years now. This makes the \brief markers into our comments redundant. Since they are a visual distraction and we don't want to encourage more \brief markers in new code either, this patch removes them all. Patch produced by for i in $(git grep -l '\\brief'); do perl -pi -e 's/\\brief //g' $i & done Differential Revision: https://reviews.llvm.org/D46290 llvm-svn: 331272
* [SimplifyCFG] Use BB::instructionsWithoutDebug to skip DbgInfo (NFC).Florian Hahn2018-04-301-37/+14
| | | | | | | | | | | | | | This patch updates some code responsible the skip debug info to use BasicBlock::instructionsWithoutDebug. I think this makes things slightly simpler and more direct. Reviewers: aprantl, vsk, hans, danielcdh Reviewed By: hans Differential Revision: https://reviews.llvm.org/D46252 llvm-svn: 331221
* [Transforms] Change std::sort to llvm::sort in response to r327219Mandeep Singh Grang2018-04-131-1/+1
| | | | | | | | | | | | | | | | | | | | | | Summary: r327219 added wrappers to std::sort which randomly shuffle the container before sorting. This will help in uncovering non-determinism caused due to undefined sorting order of objects having the same key. To make use of that infrastructure we need to invoke llvm::sort instead of std::sort. Note: This patch is one of a series of patches to replace *all* std::sort to llvm::sort. Refer the comments section in D44363 for a list of all the required patches. Reviewers: kcc, pcc, danielcdh, jmolloy, sanjoy, dberlin, ruiu Reviewed By: ruiu Subscribers: ruiu, llvm-commits Differential Revision: https://reviews.llvm.org/D45142 llvm-svn: 330059
* [SimplifyCFG] Teach merge conditional stores to handle cases where the ↵Craig Topper2018-04-041-1/+16
| | | | | | | | | | | | | | | | | | | PostBB has more than 2 predecessors by inserting a new block for the store. Summary: Currently merge conditional stores can't handle cases where PostBB (the block we need to move the store to) has more than 2 predecessors. This patch removes that restriction by creating a new block with only the 2 predecessors we care about and an unconditional branch to the original block. This provides a place to put the store. Reviewers: efriedma, jmolloy, ABataev Reviewed By: efriedma Subscribers: llvm-commits Differential Revision: https://reviews.llvm.org/D39760 llvm-svn: 329142
* [SimplifyCFG] Create attribute for fuzzing-specific optimizations.Matt Morehouse2018-03-221-0/+7
| | | | | | | | | | | | | | | | | | | | | | Summary: When building with libFuzzer, converting control flow to selects or obscuring the original operands of CMPs reduces the effectiveness of libFuzzer's heuristics. This patch provides an attribute to disable or modify certain optimizations for optimal fuzzing signal. Provides a less aggressive alternative to https://reviews.llvm.org/D44057. Reviewers: vitalybuka, davide, arsenm, hfinkel Reviewed By: vitalybuka Subscribers: junbuml, mehdi_amini, wdng, javed.absar, hiraditya, llvm-commits, kcc Differential Revision: https://reviews.llvm.org/D44232 llvm-svn: 328214
* Fix a couple of layering violations in TransformsDavid Blaikie2018-03-211-1/+1
| | | | | | | | | | | | | Remove #include of Transforms/Scalar.h from Transform/Utils to fix layering. Transforms depends on Transforms/Utils, not the other way around. So remove the header and the "createStripGCRelocatesPass" function declaration (& definition) that is unused and motivated this dependency. Move Transforms/Utils/Local.h into Analysis because it's used by Analysis/MemoryBuiltins.cpp. llvm-svn: 328165
* [Debug] Retain both copies of debug intrinsics in HoistThenElseCodeToIfUlrich Weigand2018-03-151-25/+38
| | | | | | | | | | | | | | | | | | | | | | | | When hoisting common code from the "then" and "else" branches of a condition to before the "if", the HoistThenElseCodeToIf routine will attempt to merge the debug location associated with the two original copies of the hoisted instruction. This is a problem in the special case where the hoisted instruction is a debug info intrinsic, since for those the debug location is considered part of the intrinsic and attempting to modify it may resut in invalid IR. This is the underlying cause of PR36410. This patch fixes the problem by handling debug info intrinsics specially: instead of hoisting one copy and merging the two locations, the code now simply hoists both copies, each with its original location intact. Note that this is still only done in the case where both original copies are otherwise (i.e. apart from location metadata) identical. Reviewed By: aprantl Differential Revision: https://reviews.llvm.org/D44312 llvm-svn: 327622
* Revert "[Debug] Retain both sets of debug intrinsics in HoistThenElseCodeToIf"Ulrich Weigand2018-03-091-14/+25
| | | | | | This reverts commit r327175 as problems in debug info generation were shown. llvm-svn: 327176
* [Debug] Retain both sets of debug intrinsics in HoistThenElseCodeToIfUlrich Weigand2018-03-091-25/+14
| | | | | | | | | | | | | | | | | | | | | When hoisting common code from the "then" and "else" branches of a condition to before the "if", there is no need to require that debug intrinsics match before moving them (and merging them). Instead, we can simply always keep all debug intrinsics from both sides of the "if". This fixes PR36410, which describes a problem where as a result of the attempt to merge debug locations for two debug intrinsics we end up with an invalid intrinsic, where the scope indicated in the !dbg location no longer matches the scope of the variable tracked by the intrinsic. In addition, this has the benefit that we no longer throw away information that is actually still valid, helping to generate better debug data. Reviewed By: vsk Differential Revision: https://reviews.llvm.org/D44312 llvm-svn: 327175
* [SimplifyCFG] Re-apply Relax restriction for folding unconditional branchesSerguei Katkov2018-02-081-1/+4
| | | | | | | | | | | | | | | | | | | | | The commit rL308422 introduces a restriction for folding unconditional branches. Specifically if empty block with unconditional branch leads to header of the loop then elimination of this basic block is prohibited. However it seems this condition is redundantly strict. If elimination of this basic block does not introduce more back edges then we can eliminate this block. The patch implements this relax of restriction. The test profile/Linux/counter_promo_nest.c in compiler-rt project is updated to meet this change. Reviewers: efriedma, mcrosier, pacxx, hsung, davidxl Reviewed By: pacxx Subscribers: llvm-commits Differential Revision: https://reviews.llvm.org/D42691 llvm-svn: 324572
* Revert [SimplifyCFG] Relax restriction for folding unconditional branchesSerguei Katkov2018-02-051-4/+1
| | | | | | | | | | | The patch causes the failure of the test compiler-rt/test/profile/Linux/counter_promo_nest.c To unblock buildbot, revert the patch while investigation is in progress. Differential Revision: https://reviews.llvm.org/D42691 llvm-svn: 324214
* [SimplifyCFG] Relax restriction for folding unconditional branchesSerguei Katkov2018-02-051-1/+4
| | | | | | | | | | | | | | | | | | The commit rL308422 introduces a restriction for folding unconditional branches. Specifically if empty block with unconditional branch leads to header of the loop then elimination of this basic block is prohibited. However it seems this condition is redundantly strict. If elimination of this basic block does not introduce more back edges then we can eliminate this block. The patch implements this relax of restriction. Reviewers: efriedma, mcrosier, pacxx, hsung, davidxl Reviewed By: pacxx Subscribers: llvm-commits Differential Revision: https://reviews.llvm.org/D42691 llvm-svn: 324208
* [NFC] Commit to mention that r322248 is actually made by AndrewScheideckerMarcello Maggioni2018-01-111-1/+1
| | | | llvm-svn: 322249
* [SimplifyCFG] Add cut-off for InitializeUniqueCases.Marcello Maggioni2018-01-111-13/+25
| | | | | | | | | | | | | The function can take a significant amount of time on some complicated test cases, but for the currently only use of the function we can stop the initialization much earlier when we find out we are going to discard the result anyway in the caller of the function. Adding configurable cut-off points so that we avoid wasting time. NFCI. llvm-svn: 322248
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