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* [SimplifyCFG] mergeConditionalStoreToAddress(): try to pacify MSANRoman Lebedev2019-09-181-1/+1
| | | | | | | | MSAN bot complains that there is use-of-uninitialized-value of this FreeStores later in IsWorthwhile(). Perhaps FreeStores needs to be stored in a vector? llvm-svn: 372262
* [SimplifyCFG] mergeConditionalStoreToAddress(): consider cost, not ↵Roman Lebedev2019-09-181-42/+50
| | | | | | | | | | | | | | | | | | | | | | | | | | instruction count Summary: As it can be see in the changed test, while `div` is really costly, we were speculating it. This does not seem correct. Also, the old code would run for every single insturuction in BB, instead of eagerly bailing out as soon as there are too many instructions. This function still has a problem that `PHINodeFoldingThreshold` is per-basic-block, while it should be for all the basic blocks. Reviewers: efriedma, craig.topper, dmgreen, jmolloy Reviewed By: jmolloy Subscribers: xbolva00, hiraditya, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D67315 llvm-svn: 372255
* [SimplifyCFG] FoldTwoEntryPHINode(): consider *total* speculation cost, not ↵Roman Lebedev2019-09-161-13/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | per-BB cost Summary: Previously, if the threshold was 2, we were willing to speculatively execute 2 cheap instructions in both basic blocks (thus we were willing to speculatively execute cost = 4), but weren't willing to speculate when one BB had 3 instructions and other one had no instructions, even thought that would have total cost of 3. This looks inconsistent to me. I don't think `cmov`-like instructions will start executing until both of it's inputs are available: https://godbolt.org/z/zgHePf So i don't see why the existing behavior is the correct one. Also, let's add it's own `cl::opt` for this threshold, with default=4, so it is not stricter than the previous threshold: will allow to fold when there are 2 BB's each with cost=2. And since the logic has changed, it will also allow to fold when one BB has cost=3 and other cost=1, or there is only one BB with cost=4. This is an alternative solution to D65148: This fix is mainly motivated by `signbit-like-value-extension.ll` test. That pattern comes up in JPEG decoding, see e.g. `Figure F.12 – Extending the sign bit of a decoded value in V` of `ITU T.81` (JPEG specification). That branch is not predictable, and it is within the innermost loop, so the fact that that pattern ends up being stuck with a branch instead of `select` (i.e. `CMOV` for x86) is unlikely to be beneficial. This has great results on the final assembly (vanilla test-suite + RawSpeed): (metric pass - D67240) | metric | old | new | delta | % | | x86-mi-counting.NumMachineFunctions | 37720 | 37721 | 1 | 0.00% | | x86-mi-counting.NumMachineBasicBlocks | 773545 | 771181 | -2364 | -0.31% | | x86-mi-counting.NumMachineInstructions | 7488843 | 7486442 | -2401 | -0.03% | | x86-mi-counting.NumUncondBR | 135770 | 135543 | -227 | -0.17% | | x86-mi-counting.NumCondBR | 423753 | 422187 | -1566 | -0.37% | | x86-mi-counting.NumCMOV | 24815 | 25731 | 916 | 3.69% | | x86-mi-counting.NumVecBlend | 17 | 17 | 0 | 0.00% | We significantly decrease basic block count, notably decrease instruction count, significantly decrease branch count and very significantly increase `cmov` count. Performance-wise, unsurprisingly, this has great effect on target RawSpeed benchmark. I'm seeing 5 **major** improvements: ``` Benchmark Time CPU Time Old Time New CPU Old CPU New ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Samsung/NX3000/_3184416.SRW/threads:8/process_time/real_time_pvalue 0.0000 0.0000 U Test, Repetitions: 49 vs 49 Samsung/NX3000/_3184416.SRW/threads:8/process_time/real_time_mean -0.3064 -0.3064 226.9913 157.4452 226.9800 157.4384 Samsung/NX3000/_3184416.SRW/threads:8/process_time/real_time_median -0.3057 -0.3057 226.8407 157.4926 226.8282 157.4828 Samsung/NX3000/_3184416.SRW/threads:8/process_time/real_time_stddev -0.4985 -0.4954 0.3051 0.1530 0.3040 0.1534 Kodak/DCS760C/86L57188.DCR/threads:8/process_time/real_time_pvalue 0.0000 0.0000 U Test, Repetitions: 49 vs 49 Kodak/DCS760C/86L57188.DCR/threads:8/process_time/real_time_mean -0.1747 -0.1747 80.4787 66.4227 80.4771 66.4146 Kodak/DCS760C/86L57188.DCR/threads:8/process_time/real_time_median -0.1742 -0.1743 80.4686 66.4542 80.4690 66.4436 Kodak/DCS760C/86L57188.DCR/threads:8/process_time/real_time_stddev +0.6089 +0.5797 0.0670 0.1078 0.0673 0.1062 Sony/DSLR-A230/DSC08026.ARW/threads:8/process_time/real_time_pvalue 0.0000 0.0000 U Test, Repetitions: 49 vs 49 Sony/DSLR-A230/DSC08026.ARW/threads:8/process_time/real_time_mean -0.1598 -0.1598 171.6996 144.2575 171.6915 144.2538 Sony/DSLR-A230/DSC08026.ARW/threads:8/process_time/real_time_median -0.1598 -0.1597 171.7109 144.2755 171.7018 144.2766 Sony/DSLR-A230/DSC08026.ARW/threads:8/process_time/real_time_stddev +0.4024 +0.3850 0.0847 0.1187 0.0848 0.1175 Canon/EOS 77D/IMG_4049.CR2/threads:8/process_time/real_time_pvalue 0.0000 0.0000 U Test, Repetitions: 49 vs 49 Canon/EOS 77D/IMG_4049.CR2/threads:8/process_time/real_time_mean -0.0550 -0.0551 280.3046 264.8800 280.3017 264.8559 Canon/EOS 77D/IMG_4049.CR2/threads:8/process_time/real_time_median -0.0554 -0.0554 280.2628 264.7360 280.2574 264.7297 Canon/EOS 77D/IMG_4049.CR2/threads:8/process_time/real_time_stddev +0.7005 +0.7041 0.2779 0.4725 0.2775 0.4729 Canon/EOS 5DS/2K4A9929.CR2/threads:8/process_time/real_time_pvalue 0.0000 0.0000 U Test, Repetitions: 49 vs 49 Canon/EOS 5DS/2K4A9929.CR2/threads:8/process_time/real_time_mean -0.0354 -0.0355 316.7396 305.5208 316.7342 305.4890 Canon/EOS 5DS/2K4A9929.CR2/threads:8/process_time/real_time_median -0.0354 -0.0356 316.6969 305.4798 316.6917 305.4324 Canon/EOS 5DS/2K4A9929.CR2/threads:8/process_time/real_time_stddev +0.0493 +0.0330 0.3562 0.3737 0.3563 0.3681 ``` That being said, it's always best-effort, so there will likely be cases where this worsens things. Reviewers: efriedma, craig.topper, dmgreen, jmolloy, fhahn, Carrot, hfinkel, chandlerc Reviewed By: jmolloy Subscribers: xbolva00, hiraditya, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D67318 llvm-svn: 372009
* [SimplifyCFG] SpeculativelyExecuteBB(): It's SpeculatedInstructions, not ↵Roman Lebedev2019-09-071-7/+7
| | | | | | | | | SpeculationCost It counts the number of instructions we are ok speculating (at most 1 there), not their cost, so rename accordingly. llvm-svn: 371294
* [SimplifyCFG] Don't SimplifyBranchOnICmpChain with ExtraCaseVitaly Buka2019-09-051-1/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: Here we try to avoid issues with "explicit branch" with SimplifyBranchOnICmpChain which can check on undef. Msan by design reports branches on uninitialized memory and undefs, so we have false report here. In general msan does not like when we convert ``` // If at least one of them is true we can MSAN is ok if another is undefs if (a || b) return; ``` into ``` // If 'a' is undef MSAN will complain even if 'b' is true if (a) return; if (b) return; ``` Example Before optimization we had something like this: ``` while (true) { bool maybe_undef = doStuff(); while (true) { char c = getChar(); if (c != 10 && c != 13) continue break; } // we know that c == 10 || c == 13 if we get here, // so msan know that branch is not affected by maybe_undef if (maybe_undef || c == 10 || c == 13) continue; return; } ``` SimplifyBranchOnICmpChain will convert that into ``` while (true) { bool maybe_undef = doStuff(); while (true) { char c = getChar(); if (c != 10 && c != 13) continue; break; } // however msan will complain here: if (maybe_undef) continue; // we know that c == 10 || c == 13, so either way we will get continue switch(c) { case 10: continue; case 13: continue; } return; } ``` Reviewers: eugenis, efriedma Reviewed By: eugenis, efriedma Subscribers: hiraditya, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D67205 llvm-svn: 371138
* [SimplifyCFG] Skip sinking common lifetime markers of `alloca`.Michael Liao2019-08-291-6/+25
| | | | | | | | | | | | | | | Summary: - Similar to the workaround in fix of PR30188, skip sinking common lifetime markers of `alloca`. They are mostly left there after inlining functions in branches. Subscribers: hiraditya, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D66950 llvm-svn: 370376
* [SimplifyCFG] FoldTwoEntryPHINode(): don't bailout on i1 PHI's if we can ↵Roman Lebedev2019-08-291-3/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | hoist a 'not' from incoming values Summary: As it can be seen in the tests in D65143/D65144, even though we have formed an '@llvm.umul.with.overflow' and got rid of potential for division-by-zero, the control flow remains, we still have that branch. We have this condition: ``` // Don't fold i1 branches on PHIs which contain binary operators // These can often be turned into switches and other things. if (PN->getType()->isIntegerTy(1) && (isa<BinaryOperator>(PN->getIncomingValue(0)) || isa<BinaryOperator>(PN->getIncomingValue(1)) || isa<BinaryOperator>(IfCond))) return false; ``` which was added back in rL121764 to help with `select` formation i think? That check prevents us to flatten the CFG here, even though we know we no longer need that guard and will be able to drop everything but the '@llvm.umul.with.overflow' + `not`. As it can be seen from tests, we end here because the `not` is being sinked into the PHI's incoming values by InstCombine, so we can't workaround this by hoisting it to after PHI. Thus i suggest that we relax that check to not bailout if we'd get to hoist the `not`. Reviewers: craig.topper, spatel, fhahn, nikic Reviewed By: spatel Subscribers: hiraditya, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D65147 llvm-svn: 370349
* [Transforms] Do not drop !preserve.access.index metadataYonghong Song2019-08-031-1/+2
| | | | | | | | | | | | | | | Currently, when a GVN or CSE optimization happens, the llvm.preserve.access.index metadata is dropped. This caused a problem for BPF AbstructMemberOffset phase as it relies on the metadata (debuginfo types). This patch added proper hooks in lib/Transforms to preserve !preserve.access.index metadata. A test case is added to ensure metadata is preserved under CSE. Differential Revision: https://reviews.llvm.org/D65700 llvm-svn: 367769
* [SimplifyCFG] Cleanup redundant conditions [NFC].Alina Sbirlea2019-08-021-10/+8
| | | | | | | | | | | | | | | | | | Summary: Since the for loop iterates over BB's predecessors, the branch conditions found must have BB as one of the successors. For an unconditional branch the successor must be BB, added `assert`. For a conditional branch, one of the two successors must be BB, simplify `else if` to `else` and `assert`. Sink common instructions outside the if/else block. Reviewers: sanjoy.google Subscribers: jlebar, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D65596 llvm-svn: 367699
* [SimplifyCFG] Mark missed Changed to true.Alina Sbirlea2019-08-011-0/+1
| | | | | | | | | | | | | | | | Summary: DominatorTree is invalid after SimplifyCFG because of a missed `Changed = true` when simplifying a branch condition and removing an edge. Resolves PR42272. Reviewers: zhizhouy, manojgupta Subscribers: jlebar, sanjoy.google, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D65490 llvm-svn: 367596
* [SimplifyCFG] avoid crashing after simplifying a switch (PR42737)Sanjay Patel2019-07-251-8/+17
| | | | | | | | Later code in TryToSimplifyUncondBranchFromEmptyBlock() assumes that we have cleaned up unreachable blocks, but that was not happening with this switch transform. llvm-svn: 367037
* Fix parameter name comments using clang-tidy. NFC.Rui Ueyama2019-07-161-1/+1
| | | | | | | | | | | | | | | | | | | | | This patch applies clang-tidy's bugprone-argument-comment tool to LLVM, clang and lld source trees. Here is how I created this patch: $ git clone https://github.com/llvm/llvm-project.git $ cd llvm-project $ mkdir build $ cd build $ cmake -GNinja -DCMAKE_BUILD_TYPE=Debug \ -DLLVM_ENABLE_PROJECTS='clang;lld;clang-tools-extra' \ -DCMAKE_EXPORT_COMPILE_COMMANDS=On -DLLVM_ENABLE_LLD=On \ -DCMAKE_C_COMPILER=clang -DCMAKE_CXX_COMPILER=clang++ ../llvm $ ninja $ parallel clang-tidy -checks='-*,bugprone-argument-comment' \ -config='{CheckOptions: [{key: StrictMode, value: 1}]}' -fix \ ::: ../llvm/lib/**/*.{cpp,h} ../clang/lib/**/*.{cpp,h} ../lld/**/*.{cpp,h} llvm-svn: 366177
* [SimplifyCFG] NFC, prof branch_weighs handling is simplifiedYevgeny Rouban2019-06-181-49/+15
| | | | | | | | | Using the new SwitchInstProfUpdateWrapper this patch simplifies 3 places of prof branch_weights handling. Differential Revision: https://reviews.llvm.org/D62123 llvm-svn: 363652
* PHINode: introduce setIncomingValueForBlock() function, and use it.Whitney Tsang2019-06-171-2/+1
| | | | | | | | | | | | | | | | Summary: There is PHINode::getBasicBlockIndex() and PHINode::setIncomingValue() but no function to replace incoming value for a specified BasicBlock* predecessor. Clearly, there are a lot of places that could use that functionality. Reviewer: craig.topper, lebedev.ri, Meinersbur, kbarton, fhahn Reviewed By: Meinersbur, fhahn Subscribers: fhahn, hiraditya, zzheng, jsji, llvm-commits Tag: LLVM Differential Revision: https://reviews.llvm.org/D63338 llvm-svn: 363566
* Re-commit r357452 (take 3): "SimplifyCFG SinkCommonCodeFromPredecessors: ↵Hans Wennborg2019-06-171-14/+15
| | | | | | | | | | | Also sink function calls without used results (PR41259)" Third time's the charm. This was reverted in r363220 due to being suspected of an internal benchmark regression and a test failure, none of which turned out to be caused by this. llvm-svn: 363529
* [SimplifyCFG] Fix prof branch_weights MD while removing unreachable switch casesYevgeny Rouban2019-06-171-4/+5
| | | | | | | | | | | SimplifyCFG has a bug that results in inconsistent prof branch_weights metadata if unreachable switch cases are removed. This patch fixes this bug by making use of the newly introduced SwitchInstProfUpdateWrapper class (see patch D62122). A new test is created. Differential Revision: https://reviews.llvm.org/D62186 llvm-svn: 363527
* [SimpligyCFG] NFC intended, remove GCD that was only used for powers of twoShawn Landden2019-06-141-13/+11
| | | | | | | | | | | | and replace with an equilivent countTrailingZeros. GCD is much more expensive than this, with repeated division. This depends on D60823 Differential Revision: https://reviews.llvm.org/D61151 llvm-svn: 363422
* [SimplifyCFG] reverting preliminary Switch patches againShawn Landden2019-06-131-11/+13
| | | | | | | | | This reverts 363226 and 363227, both NFC intended I swear I fixed the test case that is failing, and ran the tests, but I will look into it again. llvm-svn: 363229
* [SimpligyCFG] NFC intended, remove GCD that was only used for powers of twoShawn Landden2019-06-131-13/+11
| | | | | | | | | | | | and replace with an equilivent countTrailingZeros. GCD is much more expensive than this, with repeated division. This depends on D60823 Differential Revision: https://reviews.llvm.org/D61151 llvm-svn: 363227
* Revert r361811: 'Re-commit r357452 (take 2): "SimplifyCFG ↵David L. Jones2019-06-131-15/+14
| | | | | | | | | | | | | | | | SinkCommonCodeFromPredecessors ...' We have observed some failures with internal builds with this revision. - Performance regressions: - llvm's SingleSource/Misc evalloop shows performance regressions (although these may be red herrings). - Benchmarks for Abseil's SwissTable. - Correctness: - Failures for particular libicu tests when building the Google AppEngine SDK (for PHP). hwennborg has already been notified, and is aware of reproducer failures. llvm-svn: 363220
* Re-commit r357452 (take 2): "SimplifyCFG SinkCommonCodeFromPredecessors: ↵Hans Wennborg2019-05-281-14/+15
| | | | | | | | | | | | | | | | | | | | Also sink function calls without used results (PR41259)" This was reverted in r360086 as it was supected of causing mysterious test failures internally. However, it was never concluded that this patch was the root cause. > The code was previously checking that candidates for sinking had exactly > one use or were a store instruction (which can't have uses). This meant > we could sink call instructions only if they had a use. > > That limitation seemed a bit arbitrary, so this patch changes it to > "instruction has zero or one use" which seems more natural and removes > the need to special-case stores. > > Differential revision: https://reviews.llvm.org/D59936 llvm-svn: 361811
* [SimplifyCFG] back out all SwitchInst commitsShawn Landden2019-05-261-90/+71
| | | | | | | | They caused the sanitizer builds to fail. My suspicion is the change the countLeadingZeros(). llvm-svn: 361736
* [SimplifyCFG] ReduceSwitchRange: Improve on the case where the SubThreshold ↵Shawn Landden2019-05-261-14/+24
| | | | | | doesn't trigger llvm-svn: 361728
* [SimplifyCFG] Run ReduceSwitchRange unconditionally, generalizeShawn Landden2019-05-261-56/+66
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Rather than gating on "isSwitchDense" (resulting in necessesarily sparse lookup tables even when they were generated), always run this quite cheap transform. This transform is useful not just for generating tables. LowerSwitch also wants this: read LowerSwitch.cpp:257. Be careful to not generate worse code, by introducing a SubThreshold heuristic. Instead of just sorting by signed, generalize the finding of the best base. And now that it is run unconditionally, do not replicate its functionality in SwitchToLookupTable (which could use a Sub when having a hole is smaller, hence the SubThreshold heuristic located in a single place). This simplifies SwitchToLookupTable, and fixes some ugly corner cases due to the use of signed numbers, such as a table containing i16 32768 and 32769, of which 32769 would be interpreted as -32768, and now the code thinks the table is size 65536. (We still use unconditional subtraction when building a single-register mask, but I think this whole block should go when the more general sparse map is added, which doesn't leave empty holes in the table.) And the reason test4 and test5 did not trigger was documented wrong: it was because they were not considered sufficiently "dense". Also, fix generation of invalid LLVM-IR: shl by bit-width. llvm-svn: 361727
* [SimpligyCFG] NFC, remove GCD that was only used for powers of twoShawn Landden2019-05-261-12/+10
| | | | | | | | | | and replace with an equilivent countTrailingZeros. GCD is much more expensive than this, with repeated division. This depends on D60823 llvm-svn: 361726
* [Support] make countLeadingZeros() and countTrailingZeros() return unsignedShawn Landden2019-05-261-11/+12
| | | | | | | | | This matches countLeadingOnes() and countTrailingOnes(), and APInt's countLeadingZeros() and countTrailingZeros(). (as well as __builtin_clzll()) llvm-svn: 361724
* [SimplifyCFG] Added condition assumption for unreachable blocksDavid Bolvansky2019-05-251-0/+3
| | | | | | | | | | | | | | | | Summary: PR41688 Reviewers: spatel, efriedma, craig.topper, hfinkel, reames Reviewed By: hfinkel Subscribers: javed.absar, dmgreen, fhahn, hfinkel, reames, nikic, lebedev.ri, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D61409 llvm-svn: 361707
* [MemorySSA] Teach LoopSimplify to preserve MemorySSA.Alina Sbirlea2019-05-081-10/+24
| | | | | | | | | | | | | | | Summary: Preserve MemorySSA in LoopSimplify, in the old pass manager, if the analysis is available. Do not preserve it in the new pass manager. Update tests. Subscribers: nemanjai, jlebar, javed.absar, Prazek, kbarton, zzheng, jsji, llvm-commits, george.burgess.iv, chandlerc Tags: #llvm Differential Revision: https://reviews.llvm.org/D60833 llvm-svn: 360270
* Test commit accessOrlando Cazalet-Hyams2019-05-071-2/+2
| | | | llvm-svn: 360125
* Revert "Re-commit r357452: SimplifyCFG SinkCommonCodeFromPredecessors: Also ↵Jordan Rupprecht2019-05-061-15/+14
| | | | | | | | | | sink function calls without used results (PR41259)" This reverts r357452 (git commit 21eb771dcb5c11d7500fa6ad551c97a921997f05). This was causing strange optimization-related test failures on an internal test. Will followup with more details offline. llvm-svn: 360086
* Re-commit r357452: SimplifyCFG SinkCommonCodeFromPredecessors: Also sink ↵Hans Wennborg2019-04-161-14/+15
| | | | | | | | | | | | | | | | | | | function calls without used results (PR41259) The original commit caused false positives from AddressSanitizer's use-after-scope checks, which have now been fixed in r358478. > The code was previously checking that candidates for sinking had exactly > one use or were a store instruction (which can't have uses). This meant > we could sink call instructions only if they had a use. > > That limitation seemed a bit arbitrary, so this patch changes it to > "instruction has zero or one use" which seems more natural and removes > the need to special-case stores. > > Differential revision: https://reviews.llvm.org/D59936 llvm-svn: 358483
* Revert r357452 - 'SimplifyCFG SinkCommonCodeFromPredecessors: Also sink ↵David L. Jones2019-04-041-15/+14
| | | | | | | | | | function calls without used results (PR41259)' This revision causes tests to fail under ASAN. Since the cause of the failures is not clear (could be ASAN, could be a Clang bug, could be a bug in this revision), the safest course of action seems to be to revert while investigating. llvm-svn: 357667
* SimplifyCFG SinkCommonCodeFromPredecessors: Also sink function calls without ↵Hans Wennborg2019-04-021-14/+15
| | | | | | | | | | | | | | | | used results (PR41259) The code was previously checking that candidates for sinking had exactly one use or were a store instruction (which can't have uses). This meant we could sink call instructions only if they had a use. That limitation seemed a bit arbitrary, so this patch changes it to "instruction has zero or one use" which seems more natural and removes the need to special-case stores. Differential revision: https://reviews.llvm.org/D59936 llvm-svn: 357452
* [SimplifyCFG] Retain debug info when threading jumps with critical edgesJeremy Morse2019-03-111-1/+2
| | | | | | | | | | | | | | | | | | | | Fixes bug 38023: https://bugs.llvm.org/show_bug.cgi?id=38023 The SimplifyCFG pass will perform jump threading in some cases where doing so is trivial and would simplify the CFG. When folding a series of blocks with redundant conditional branches into an unconditional "critical edge" block, it does not keep the debug location associated with the previous conditional branch. This patch fixes the bug described by copying the debug info from the old conditional branch to the new unconditional branch instruction, and adds a regression test for the SimplifyCFG pass that covers this case. Patch by Stephen Tozer! Differential Revision: https://reviews.llvm.org/D59206 llvm-svn: 355833
* [NFC] Rename DontDeleteUselessPHIs --> KeepOneInputPHIsMax Kazantsev2019-02-121-2/+2
| | | | llvm-svn: 353801
* Implementation of asm-goto support in LLVMCraig Topper2019-02-081-3/+10
| | | | | | | | | | | | | | | | | | | | | | | | | 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
* [opaque pointer types] Pass value type to LoadInst creation.James Y Knight2019-02-011-1/+3
| | | | | | | | | 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
* [DebugInfo] Remove un-necessary logic from HoistThenElseCodeToIfJeremy Morse2019-01-141-12/+1
| | | | | | | | | | | | | | | | | Following PR39807, the way in which SimplifyCFG hoists common code on branch paths was fixed in r347782. However this left extra code hanging around HoistThenElseCodeToIf that wasn't necessary and needlessly complicated matters -- we no longer need to look up through the 'if' basic block to find a location for hoisted 'select' insts, we can instead use the location chosen by applyMergedLocation. This patch deletes that extra logic, and updates a regression test to reflect the new logic (selects get the merged location, not a previous insts location). Differential Revision: https://reviews.llvm.org/D55272 llvm-svn: 351058
* Introduce llvm.loop.parallel_accesses and llvm.access.group metadata.Michael Kruse2018-12-201-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The current llvm.mem.parallel_loop_access metadata has a problem in that it uses LoopIDs. LoopID unfortunately is not loop identifier. It is neither unique (there's even a regression test assigning the some LoopID to multiple loops; can otherwise happen if passes such as LoopVersioning make copies of entire loops) nor persistent (every time a property is removed/added from a LoopID's MDNode, it will also receive a new LoopID; this happens e.g. when calling Loop::setLoopAlreadyUnrolled()). Since most loop transformation passes change the loop attributes (even if it just to mark that a loop should not be processed again as llvm.loop.isvectorized does, for the versioned and unversioned loop), the parallel access information is lost for any subsequent pass. This patch unlinks LoopIDs and parallel accesses. llvm.mem.parallel_loop_access metadata on instruction is replaced by llvm.access.group metadata. llvm.access.group points to a distinct MDNode with no operands (avoiding the problem to ever need to add/remove operands), called "access group". Alternatively, it can point to a list of access groups. The LoopID then has an attribute llvm.loop.parallel_accesses with all the access groups that are parallel (no dependencies carries by this loop). This intentionally avoid any kind of "ID". Loops that are clones/have their attributes modifies retain the llvm.loop.parallel_accesses attribute. Access instructions that a cloned point to the same access group. It is not necessary for each access to have it's own "ID" MDNode, but those memory access instructions with the same behavior can be grouped together. The behavior of llvm.mem.parallel_loop_access is not changed by this patch, but should be considered deprecated. Differential Revision: https://reviews.llvm.org/D52116 llvm-svn: 349725
* [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
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