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* [JumpThreading] NFC: Don't cache F.hasProfileData()Kazu Hirata2019-11-221-3/+2
| | | | | | | | | | | | | | | | | | | | | | Summary: With this patch, we no longer cache F.hasProfileData(). We simply call the function again. I'm doing this because: - JumpThreadingPass also has a member variable named HasProfileData, which is very confusing, - the function is very lightweight, and - this patch makes JumpThreading::runOnFunction more consistent with JumpThreadingPass::run. Subscribers: hiraditya, jfb, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D70602
* [JumpThreading] Use profile data even with the new pass managerKazu Hirata2019-11-221-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: Without this patch, the jump threading pass ignores profiling data whenever we invoke the pass with the new pass manager. Specifically, JumpThreadingPass::run calls runImpl with class variable HasProfileData always set to false. In turn, runImpl sets HasProfileData to false again: HasProfileData = HasProfileData_; In the end, we don't use profiling data at all with the new pass manager. This patch fixes the problem by passing F.hasProfileData() to runImpl. The bug appears to have been introduced at: https://reviews.llvm.org/D41461 which removed local variable HasProfileData in JumpThreadingPass::run even though there was one more use left in the same function. As a result, the remaining use ended referring to the class variable instead. Note that F.hasProfileData is an extremely lightweight function, so I don't see the need to cache its result. Once this patch is approved, I'm planning to stop caching the result of F.hasProfileData in runOnFunction. Reviewers: wmi, eli.friedman Subscribers: hiraditya, jfb, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D70509
* [JumpThreading] Refactor ThreadEdgeKazu Hirata2019-11-211-9/+20
| | | | | | | | | | | | | | | | | | Summary: This patch moves various checks from ThreadEdge to new function TryThreadEdge The rational behind this is that I'd like to use ThreadEdge without its checks in my upcoming patch. This patch preserves lightweight checks as assertions in ThreadEdge. ThreadEdge does not repeat the cost check, however. Reviewers: wmi Subscribers: hiraditya, jfb, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D70338
* Sink all InitializePasses.h includesReid Kleckner2019-11-131-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This file lists every pass in LLVM, and is included by Pass.h, which is very popular. Every time we add, remove, or rename a pass in LLVM, it caused lots of recompilation. I found this fact by looking at this table, which is sorted by the number of times a file was changed over the last 100,000 git commits multiplied by the number of object files that depend on it in the current checkout: recompiles touches affected_files header 342380 95 3604 llvm/include/llvm/ADT/STLExtras.h 314730 234 1345 llvm/include/llvm/InitializePasses.h 307036 118 2602 llvm/include/llvm/ADT/APInt.h 213049 59 3611 llvm/include/llvm/Support/MathExtras.h 170422 47 3626 llvm/include/llvm/Support/Compiler.h 162225 45 3605 llvm/include/llvm/ADT/Optional.h 158319 63 2513 llvm/include/llvm/ADT/Triple.h 140322 39 3598 llvm/include/llvm/ADT/StringRef.h 137647 59 2333 llvm/include/llvm/Support/Error.h 131619 73 1803 llvm/include/llvm/Support/FileSystem.h Before this change, touching InitializePasses.h would cause 1345 files to recompile. After this change, touching it only causes 550 compiles in an incremental rebuild. Reviewers: bkramer, asbirlea, bollu, jdoerfert Differential Revision: https://reviews.llvm.org/D70211
* [JumpThreading] Fix a comment typo (NFC)Kazu Hirata2019-11-081-1/+1
| | | | | | | | | | Reviewers: kazu Subscribers: hiraditya, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D70013
* [JumpThreading] Factor out code to clone instructions (NFC)Kazu Hirata2019-11-061-31/+45
| | | | | | | | | | | | | | Summary: This patch factors out code to clone instructions -- partly for readability and partly to facilitate an upcoming patch of my own. Reviewers: wmi Subscribers: hiraditya, jfb, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D69861
* [JumpThreading] Factor out code to merge basic blocks (NFC)Kazu Hirata2019-11-051-43/+52
| | | | | | | | | | | | | | | Summary: This patch factors out code to merge a basic block with its sole successor -- partly for readability and partly to facilitate an upcoming patch of my own. Reviewers: wmi Subscribers: hiraditya, jfb, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D69852
* [JumpThreading] Factor out common code to update the SSA form (NFC)Kazu Hirata2019-11-051-75/+46
| | | | | | | | | | | | | | | Summary: This patch factors out common code to update the SSA form in JumpThreading.cpp -- partly for readability and partly to facilitate an coming patch of my own. Reviewers: wmi Subscribers: hiraditya, jfb, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D69811
* [Alignment][NFC] Convert LoadInst to MaybeAlignGuillaume Chatelet2019-10-221-1/+1
| | | | | | | | | | | | | | | | | Summary: This is patch is part of a series to introduce an Alignment type. See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html See this patch for the introduction of the type: https://reviews.llvm.org/D64790 Reviewers: courbet Subscribers: hiraditya, jfb, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D69302 llvm-svn: 375498
* JumpThreadingPass::UnfoldSelectInstr - silence static analyzer dyn_cast<> ↵Simon Pilgrim2019-10-171-1/+1
| | | | | | | | null dereference warning. NFCI. The static analyzer is warning about a potential null dereference, but we should be able to use cast<> directly and if not assert will fire for us. llvm-svn: 375103
* Change TargetLibraryInfo analysis passes to always require FunctionTeresa Johnson2019-09-071-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: This is the first change to enable the TLI to be built per-function so that -fno-builtin* handling can be migrated to use function attributes. See discussion on D61634 for background. This is an enabler for fixing handling of these options for LTO, for example. This change should not affect behavior, as the provided function is not yet used to build a specifically per-function TLI, but rather enables that migration. Most of the changes were very mechanical, e.g. passing a Function to the legacy analysis pass's getTLI interface, or in Module level cases, adding a callback. This is similar to the way the per-function TTI analysis works. There was one place where we were looking for builtins but not in the context of a specific function. See FindCXAAtExit in lib/Transforms/IPO/GlobalOpt.cpp. I'm somewhat concerned my workaround could provide the wrong behavior in some corner cases. Suggestions welcome. Reviewers: chandlerc, hfinkel Subscribers: arsenm, dschuff, jvesely, nhaehnle, mehdi_amini, javed.absar, sbc100, jgravelle-google, eraman, aheejin, steven_wu, george.burgess.iv, dexonsmith, jfb, asbirlea, gchatelet, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D66428 llvm-svn: 371284
* [JumpThreading] Stop searching predecessor when the current bb is in aWei Mi2019-07-261-1/+11
| | | | | | | | | | | | | | | | | | | unreachable loop. updatePredecessorProfileMetadata in jumpthreading tries to find the first dominating predecessor block for a PHI value by searching upwards the predecessor block chain. But jumpthreading may see some temporary IR state which contains unreachable bb not being cleaned up. If an unreachable loop happens to be on the predecessor block chain, keeping chasing the predecessor block will run into an infinite loop. The patch fixes it. Differential Revision: https://reviews.llvm.org/D65310 llvm-svn: 367154
* [JumpThreading] Fix threading with unusual PHI nodes.Eli Friedman2019-07-031-3/+16
| | | | | | | | | | | | | | | | | | | | If the block being cloned contains a PHI node, in general, we need to clone that PHI node, even though it's trivial. If the operand of the PHI is an instruction in the block being cloned, the correct value for the operand doesn't exist until SSAUpdater constructs it. We usually don't hit this issue because we try to avoid threading across loop headers, but it's possible to hit this in some cases involving irreducible CFGs. I added a flag to allow threading across loop headers to make the testcase easier to understand. Thanks to Brian Rzycki for reducing the testcase. Fixes https://bugs.llvm.org/show_bug.cgi?id=42085. Differential Revision: https://reviews.llvm.org/D63913 llvm-svn: 365094
* Simplify std::lower_bound with llvm::{bsearch,lower_bound}. NFCFangrui Song2019-06-211-2/+1
| | | | llvm-svn: 364006
* [JumpThreading] A bug fix for stale loop info after unfold selectHiroshi Yamauchi2019-05-151-1/+2
| | | | | | | | | | | | | | | | | | | | Summary: The return value of a TryToUnfoldSelect call was not checked, which led to an incorrectly preserved loop info and some crash. The original crash was reported on https://reviews.llvm.org/D59514. Reviewers: davidxl, amehsan Reviewed By: davidxl Subscribers: fhahn, brzycki, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D61920 llvm-svn: 360780
* [JumpThreading] Fix incorrect fold conditional after indirectbr/callbrBrian M. Rzycki2019-04-081-5/+1
| | | | | | | | | | | | | | | | | | | | | Fixes bug 40992: https://bugs.llvm.org/show_bug.cgi?id=40992 There is potential for miscompiled code emitted from JumpThreading when analyzing a block with one or more indirectbr or callbr predecessors. The ProcessThreadableEdges() function incorrectly folds conditional branches into an unconditional branch. This patch prevents incorrect branch folding without fully pessimizing other potential threading opportunities through the same basic block. This IR shape was manually fed in via opt and is unclear if clang and the full pass pipeline will ever emit similar code shapes. Thanks to Matthias Liedtke for the bug report and simplified IR example. Differential Revision: https://reviews.llvm.org/D60284 llvm-svn: 357930
* [JumpThreading] Retain debug info when replacing branch instructionsJeremy Morse2019-03-111-2/+5
| | | | | | | | | | | | | | | | | | | | Fixes bug 37966: https://bugs.llvm.org/show_bug.cgi?id=37966 The Jump Threading pass will replace certain conditional branch instructions with unconditional branches when it can prove that only one branch can occur. Prior to this patch, it would not carry the debug info from the old instruction to the new one. This patch fixes the bug described by copying the debug info from the conditional branch instruction to the new unconditional branch instruction, and adds a regression test for the Jump Threading pass that covers this case. Patch by Stephen Tozer! Differential Revision: https://reviews.llvm.org/D58963 llvm-svn: 355822
* [DTU] Refine the interface and logic of applyUpdatesChijun Sima2019-02-221-12/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: This patch separates two semantics of `applyUpdates`: 1. User provides an accurate CFG diff and the dominator tree is updated according to the difference of `the number of edge insertions` and `the number of edge deletions` to infer the status of an edge before and after the update. 2. User provides a sequence of hints. Updates mentioned in this sequence might never happened and even duplicated. Logic changes: Previously, removing invalid updates is considered a side-effect of deduplication and is not guaranteed to be reliable. To handle the second semantic, `applyUpdates` does validity checking before deduplication, which can cause updates that have already been applied to be submitted again. Then, different calls to `applyUpdates` might cause unintended consequences, for example, ``` DTU(Lazy) and Edge A->B exists. 1. DTU.applyUpdates({{Delete, A, B}, {Insert, A, B}}) // User expects these 2 updates result in a no-op, but {Insert, A, B} is queued 2. Remove A->B 3. DTU.applyUpdates({{Delete, A, B}}) // DTU cancels this update with {Insert, A, B} mentioned above together (Unintended) ``` But by restricting the precondition that updates of an edge need to be strictly ordered as how CFG changes were made, we can infer the initial status of this edge to resolve this issue. Interface changes: The second semantic of `applyUpdates` is separated to `applyUpdatesPermissive`. These changes enable DTU(Lazy) to use the first semantic if needed, which is quite useful in `transforms/utils`. Reviewers: kuhar, brzycki, dmgreen, grosser Reviewed By: brzycki Subscribers: hiraditya, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D58170 llvm-svn: 354669
* [DTU] Deprecate insertEdge*/deleteEdge*Chijun Sima2019-02-221-2/+2
| | | | | | | | | | | | | | | | Summary: This patch converts all existing `insertEdge*/deleteEdge*` to `applyUpdates` and marks `insertEdge*/deleteEdge*` as deprecated. Reviewers: kuhar, brzycki Reviewed By: kuhar, brzycki Subscribers: hiraditya, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D58443 llvm-svn: 354652
* Implementation of asm-goto support in LLVMCraig Topper2019-02-081-4/+7
| | | | | | | | | | | | | | | | | | | | | | | | | This patch accompanies the RFC posted here: http://lists.llvm.org/pipermail/llvm-dev/2018-October/127239.html This patch adds a new CallBr IR instruction to support asm-goto inline assembly like gcc as used by the linux kernel. This instruction is both a call instruction and a terminator instruction with multiple successors. Only inline assembly usage is supported today. This also adds a new INLINEASM_BR opcode to SelectionDAG and MachineIR to represent an INLINEASM block that is also considered a terminator instruction. There will likely be more bug fixes and optimizations to follow this, but we felt it had reached a point where we would like to switch to an incremental development model. Patch by Craig Topper, Alexander Ivchenko, Mikhail Dvoretckii Differential Revision: https://reviews.llvm.org/D53765 llvm-svn: 353563
* Move DomTreeUpdater from IR to AnalysisRichard Trieu2019-02-061-1/+1
| | | | | | | | DomTreeUpdater depends on headers from Analysis, but is in IR. This is a layering violation since Analysis depends on IR. Relocate this code from IR to Analysis to fix the layering violation. llvm-svn: 353265
* [opaque pointer types] Pass value type to LoadInst creation.James Y Knight2019-02-011-5/+5
| | | | | | | | | This cleans up all LoadInst creation in LLVM to explicitly pass the value type rather than deriving it from the pointer's element-type. Differential Revision: https://reviews.llvm.org/D57172 llvm-svn: 352911
* Update the file headers across all of the LLVM projects in the monorepoChandler Carruth2019-01-191-4/+3
| | | | | | | | | | | | | | | | | to reflect the new license. We understand that people may be surprised that we're moving the header entirely to discuss the new license. We checked this carefully with the Foundation's lawyer and we believe this is the correct approach. Essentially, all code in the project is now made available by the LLVM project under our new license, so you will see that the license headers include that license only. Some of our contributors have contributed code under our old license, and accordingly, we have retained a copy of our old license notice in the top-level files in each project and repository. llvm-svn: 351636
* [Jump Threading] Unfold a select insn that feeds a switch via a phi nodeEhsan Amiri2019-01-111-28/+70
| | | | | | | | | | | Currently when a select has a constant value in one branch and the select feeds a conditional branch (via a compare/ phi and compare) we unfold the select statement. This results in threading the conditional branch later on. Similar opportunity exists when a select (with a constant in one branch) feeds a switch (via a phi node). The patch unfolds select under this condition. A testcase is provided. llvm-svn: 350931
* [CSP, Cloning] Update DuplicateInstructionsInSplitBetween to use DomTreeUpdater.Florian Hahn2018-11-131-14/+2
| | | | | | | | | | | | | | | | | | | | | This patch updates DuplicateInstructionsInSplitBetween to update a DTU instead of applying updates to the DT directly. Given that there only are 2 users, also updated them in this patch to avoid churn. I slightly moved the code in CallSiteSplitting around to reduce the places where we have to pass in DTU. If necessary, I could split those changes in a separate patch. This fixes missing DT updates when dealing with musttail calls in CallSiteSplitting, by using DTU->deleteBB. Reviewers: junbuml, kuhar, NutshellySima, indutny, brzycki Reviewed By: NutshellySima llvm-svn: 346769
* [JumpThreading] Fix exponential time algorithm computing known values.Eli Friedman2018-11-091-19/+18
| | | | | | | | | | | | | | | | | | | ComputeValueKnownInPredecessors has a "visited" set to prevent infinite loops, since a value can be visited more than once. However, the implementation didn't prevent the algorithm from taking exponential time. Instead of removing elements from the RecursionSet one at a time, we should keep around the whole set until ComputeValueKnownInPredecessors finishes, then discard it. The testcase is synthetic because I was having trouble effectively reducing the original. But it's basically the same idea. Instead of failing, we could theoretically cache the result instead. But I don't think it would help substantially in practice. Differential Revision: https://reviews.llvm.org/D54239 llvm-svn: 346562
* [TI removal] Remove `TerminatorInst` from BasicBlockUtils.hChandler Carruth2018-10-151-8/+8
| | | | | | | | | This requires updating a number of .cpp files to adapt to the new API. I've just systematically updated all uses of `TerminatorInst` within these files te `Instruction` so thta I won't have to touch them again in the future. llvm-svn: 344498
* Re-enable "[NFC] Unify guards detection"Max Kazantsev2018-08-301-3/+3
| | | | | | | | | | rL340921 has been reverted by rL340923 due to linkage dependency from Transform/Utils to Analysis which is not allowed. In this patch this has been fixed, a new utility function moved to Analysis. Differential Revision: https://reviews.llvm.org/D51152 llvm-svn: 341014
* Revert r340921 "[NFC] Unify guards detection"Hans Wennborg2018-08-291-3/+3
| | | | | | | | | | | | | | | | | | This broke the build, see e.g. http://lab.llvm.org:8011/builders/clang-cmake-armv8-lnt/builds/4626/ http://lab.llvm.org:8011/builders/clang-ppc64be-linux-lnt/builds/18647/ http://lab.llvm.org:8011/builders/clang-cmake-x86_64-avx2-linux/builds/5856/ http://lab.llvm.org:8011/builders/lld-x86_64-freebsd/builds/22800/ > We have multiple places in code where we try to identify whether or not > some instruction is a guard. This patch factors out this logic into a separate > utility function which works uniformly in all places. > > Differential Revision: https://reviews.llvm.org/D51152 > Reviewed By: fedor.sergeev llvm-svn: 340923
* [NFC] Unify guards detectionMax Kazantsev2018-08-291-3/+3
| | | | | | | | | | | We have multiple places in code where we try to identify whether or not some instruction is a guard. This patch factors out this logic into a separate utility function which works uniformly in all places. Differential Revision: https://reviews.llvm.org/D51152 Reviewed By: fedor.sergeev llvm-svn: 340921
* [IR] Replace `isa<TerminatorInst>` with `isTerminator()`.Chandler Carruth2018-08-261-1/+1
| | | | | | | | | | | | 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
* [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
* [Dominators] Convert existing passes and utils to use the DomTreeUpdater classChijun Sima2018-08-031-37/+41
| | | | | | | | | | | | | | | | | | Summary: This patch is the second in a series of patches related to the [[ http://lists.llvm.org/pipermail/llvm-dev/2018-June/123883.html | RFC - A new dominator tree updater for LLVM ]]. It converts passes (e.g. adce/jump-threading) and various functions which currently accept DDT in local.cpp and BasicBlockUtils.cpp to use the new DomTreeUpdater class. These converted functions in utils can accept DomTreeUpdater with either UpdateStrategy and can deal with both DT and PDT held by the DomTreeUpdater. Reviewers: brzycki, kuhar, dmgreen, grosser, davide Reviewed By: brzycki Subscribers: llvm-commits Differential Revision: https://reviews.llvm.org/D48967 llvm-svn: 338814
* Revert r332168: "Reapply "[PR16756] Use SSAUpdaterBulk in JumpThreading.""Michael Zolotukhin2018-07-051-19/+15
| | | | | | | There were a couple of issues reported (PR38047, PR37929) - I'll reland the patch when I figure out and fix the rootcause. llvm-svn: 336393
* [JumpThreading] Don't try to rewrite a use if it's already valid.Michael Zolotukhin2018-06-261-10/+12
| | | | | | | | | | | | | | | | | | | Summary: When recording uses we need to rewrite after cloning a loop we need to check if the use is not dominated by the original def. The initial assumption was that the cloned basic block will introduce a new path and thus the original def will only dominate the use if they are in the same BB, but as the reproducer from PR37745 shows it's not always the case. This fixes PR37745. Reviewers: haicheng, Ka-Ka Subscribers: hiraditya, llvm-commits Differential Revision: https://reviews.llvm.org/D48111 llvm-svn: 335675
* [NFC] fix trivial typos in commentsHiroshi Inoue2018-06-141-3/+3
| | | | llvm-svn: 334687
* 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
* [JumpThreading] Fix some strange formatting of code inside LLVM_DEBUG. NFCCraig Topper2018-05-311-5/+5
| | | | | | I don't know if clang-format got confused here or what. llvm-svn: 333675
* Rename DEBUG macro to LLVM_DEBUG.Nicola Zaghen2018-05-141-38/+41
| | | | | | | | | | | | | | | | 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
* Reapply "[PR16756] Use SSAUpdaterBulk in JumpThreading."Michael Zolotukhin2018-05-121-26/+30
| | | | | | | | | Stage3/stage4 bootstrap miscompares should be fixed by a non-determinism fix in IDF (r332167). This reverts commit r330446. llvm-svn: 332168
* [STLExtras] Add distance() for ranges, pred_size(), and succ_size()Vedant Kumar2018-05-101-4/+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
* Fix the issue that ComputeValueKnownInPredecessors only handles the case whenWei Mi2018-05-011-3/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | phi is on lhs of a comparison op. For the following testcase, L1: %t0 = add i32 %m, 7 %t3 = icmp eq i32* %t2, null br i1 %t3, label %L3, label %L2 L2: %t4 = load i32, i32* %t2, align 4 br label %L3 L3: %t5 = phi i32 [ %t0, %L1 ], [ %t4, %L2 ] %t6 = icmp eq i32 %t0, %t5 br i1 %t6, label %L4, label %L5 We know if we go through the path L1 --> L3, %t6 should always be true. However currently, if the rhs of the eq comparison is phi, JumpThreading fails to evaluate %t6 to true. And we know that Instcombine cannot guarantee always canonicalizing phi to the left hand side of the comparison operation according to the operand priority comparison mechanism in instcombine. The patch handles the case when rhs of the comparison op is a phi. Differential Revision: https://reviews.llvm.org/D46275 llvm-svn: 331266
* Revert r330431.Michael Zolotukhin2018-04-201-30/+26
| | | | | | There are still stage3/stage4 miscompares :( llvm-svn: 330446
* Revert "Revert r330403 and r330413."Michael Zolotukhin2018-04-201-26/+30
| | | | | | | | | | | Reapply the patches with a fix. Thanks Ilya and Hans for the reproducer! This reverts commit r330416. The issue was that removing predecessors invalidated uses that we stored for rewrite. The fix is to finish manipulating with CFG before we select uses for rewrite. llvm-svn: 330431
* Revert r330403 and r330413.Ilya Biryukov2018-04-201-20/+16
| | | | | | | | | | | | | | | | Revert r330413: "[SSAUpdaterBulk] Use SmallVector instead of DenseMap for storing rewrites." Revert r330403 "Reapply "[PR16756] Use SSAUpdaterBulk in JumpThreading." one more time." r330403 commit seems to crash clang during our integrate while doing PGO build with the following stacktrace: #2 llvm::SSAUpdaterBulk::RewriteAllUses(llvm::DominatorTree*, llvm::SmallVectorImpl<llvm::PHINode*>*) #3 llvm::JumpThreadingPass::ThreadEdge(llvm::BasicBlock*, llvm::SmallVectorImpl<llvm::BasicBlock*> const&, llvm::BasicBlock*) #4 llvm::JumpThreadingPass::ProcessThreadableEdges(llvm::Value*, llvm::BasicBlock*, llvm::jumpthreading::ConstantPreference, llvm::Instruction*) #5 llvm::JumpThreadingPass::ProcessBlock(llvm::BasicBlock*) The crash happens while compiling 'lib/Analysis/CallGraph.cpp'. r3340413 is reverted due to conflicting changes. llvm-svn: 330416
* [SSAUpdaterBulk] Use SmallVector instead of DenseMap for storing rewrites.Michael Zolotukhin2018-04-201-3/+1
| | | | llvm-svn: 330413
* Reapply "[PR16756] Use SSAUpdaterBulk in JumpThreading." one more time.Michael Zolotukhin2018-04-201-16/+22
| | | | | | | | | Hopefully, changing set to vector removes nondeterminism detected by some bots, or the new assert will catch something. This reverts commit r330180. llvm-svn: 330403
* Revert "Reapply "[PR16756] Use SSAUpdaterBulk in JumpThreading." again."Michael Zolotukhin2018-04-171-22/+15
| | | | | | This reverts r330175. There are still stage3/stage4 miscompares. llvm-svn: 330180
* Reapply "[PR16756] Use SSAUpdaterBulk in JumpThreading." again.Michael Zolotukhin2018-04-171-15/+22
| | | | | | | | | One more, hopefully the last, bug is fixed: when forming UsesToRewrite we should ignore phi operands coming from edges that we want to delete. This reverts r329910. llvm-svn: 330175
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