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* Revert r372082 "[Clang] Pragma vectorize_width() implies vectorize(enable)"Hans Wennborg2019-09-181-8/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This broke the Chromium build. Consider the following code: float ScaleSumSamples_C(const float* src, float* dst, float scale, int width) { float fsum = 0.f; int i; #if defined(__clang__) #pragma clang loop vectorize_width(4) #endif for (i = 0; i < width; ++i) { float v = *src++; fsum += v * v; *dst++ = v * scale; } return fsum; } Compiling at -Oz, Clang now warns: $ clang++ -target x86_64 -Oz -c /tmp/a.cc /tmp/a.cc:1:7: warning: loop not vectorized: the optimizer was unable to perform the requested transformation; the transformation might be disabled or specified as part of an unsupported transformation ordering [-Wpass-failed=transform-warning] this suggests it's not actually enabling vectorization hard enough. At -Os it asserts instead: $ build.release/bin/clang++ -target x86_64 -Os -c /tmp/a.cc clang-10: /work/llvm.monorepo/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp:2734: void llvm::InnerLoopVectorizer::emitMemRuntimeChecks(llvm::Loop*, llvm::BasicBlock*): Assertion ` !BB->getParent()->hasOptSize() && "Cannot emit memory checks when optimizing for size"' failed. Of course neither of these are what the developer expected from the pragma. > Specifying the vectorization width was supposed to implicitly enable > vectorization, except that it wasn't really doing this. It was only > setting the vectorize.width metadata, but not vectorize.enable. > > This should fix PR27643. > > Differential Revision: https://reviews.llvm.org/D66290 llvm-svn: 372225
* [Clang] Pragma vectorize_width() implies vectorize(enable)Sjoerd Meijer2019-09-171-0/+8
| | | | | | | | | | | | Specifying the vectorization width was supposed to implicitly enable vectorization, except that it wasn't really doing this. It was only setting the vectorize.width metadata, but not vectorize.enable. This should fix PR27643. Differential Revision: https://reviews.llvm.org/D66290 llvm-svn: 372082
* Don't keep stale pointers to LoopInfos.Aaron Ballman2019-08-191-5/+6
| | | | | | | | CGLoopInfo was keeping pointers to parent loop LoopInfos, but when the loop info vector grew, it reallocated the storage and invalidated all of the parent pointers, causing use-after-free. Manage the lifetimes of the LoopInfos separately so that the pointers aren't stale. Patch by Bevin Hansson. llvm-svn: 369259
* [Clang] Pragma vectorize_predicate implies vectorizeSjoerd Meijer2019-08-151-6/+15
| | | | | | | | | | New pragma "vectorize_predicate(enable)" now implies "vectorize(enable)", and it is ignored when vectorization is disabled with e.g. "vectorize(disable) vectorize_predicate(enable)". Differential Revision: https://reviews.llvm.org/D65776 llvm-svn: 368970
* [Clang] New loop pragma vectorize_predicateSjoerd Meijer2019-07-251-1/+27
| | | | | | | | | | | | | | | | | | | This adds a new vectorize predication loop hint: #pragma clang loop vectorize_predicate(enable) that can be used to indicate to the vectoriser that all (load/store) instructions should be predicated (masked). This allows, for example, folding of the remainder loop into the main loop. This patch will be followed up with D64916 and D65197. The former is a refactoring in the loopvectorizer and the groundwork to make tail loop folding a more general concept, and in the latter the actual tail loop folding transformation will be implemented. Differential Revision: https://reviews.llvm.org/D64744 llvm-svn: 366989
* [CodeGen] Generate follow-up metadata for loops with more than one ↵Michael Kruse2019-04-011-91/+449
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | transformation. Before this patch, CGLoop would dump all transformations for a loop into a single LoopID without encoding any order in which to apply them. rL348944 added the possibility to encode a transformation order using followup-attributes. When a loop has more than one transformation, use the follow-up attribute define the order in which they are applied. The emitted order is the defacto order as defined by the current LLVM pass pipeline, which is: LoopFullUnrollPass LoopDistributePass LoopVectorizePass LoopUnrollAndJamPass LoopUnrollPass MachinePipeliner This patch should therefore not change the assembly output, assuming that all explicit transformations can be applied, and no implicit transformations in-between. In the former case, WarnMissedTransformationsPass should emit a warning (except for MachinePipeliner which is not implemented yet). The latter could be avoided by adding 'llvm.loop.disable_nonforced' attributes. Because LoopUnrollAndJamPass processes a loop nest, generation of the MDNode is delayed to after the inner loop metadata have been processed. A temporary LoopID is therefore used to annotate instructions and RAUW'ed by the actual LoopID later. Differential Revision: https://reviews.llvm.org/D57978 llvm-svn: 357415
* [OpenCL] Generate 'unroll.enable' metadata for ↵Andrew Savonichev2019-03-201-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | __attribute__((opencl_unroll_hint)) Summary: [OpenCL] Generate 'unroll.enable' metadata for __attribute__((opencl_unroll_hint)) For both !{!"llvm.loop.unroll.enable"} and !{!"llvm.loop.unroll.full"} the unroller will try to fully unroll a loop unless the trip count is not known at compile time. In that case for '.full' metadata no unrolling will be processed, while for '.enable' the loop will be partially unrolled with a heuristically chosen unroll factor. See: docs/LanguageExtensions.rst From https://www.khronos.org/registry/OpenCL/sdk/2.0/docs/man/xhtml/attributes-loopUnroll.html __attribute__((opencl_unroll_hint)) for (int i=0; i<2; i++) { ... } In the example above, the compiler will determine how much to unroll the loop. Before the patch for __attribute__((opencl_unroll_hint)) was generated metadata !{!"llvm.loop.unroll.full"}, which limits ability of loop unroller to decide, how much to unroll the loop. Reviewers: Anastasia, yaxunl Reviewed By: Anastasia Subscribers: zzheng, dmgreen, jdoerfert, cfe-commits, asavonic, AlexeySotkin Tags: #clang Differential Revision: https://reviews.llvm.org/D59493 llvm-svn: 356571
* 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
* Add two new pragmas for controlling software pipelining optimizations.Aaron Ballman2019-01-041-2/+36
| | | | | | | | This patch adds #pragma clang loop pipeline and #pragma clang loop pipeline_initiation_interval for debugging or reducing compile time purposes. It is possible to disable SWP for concrete loops to save compilation time or to find bugs by not doing SWP to certain loops. It is possible to set value of initiation interval to concrete number to save compilation time by not doing extra pipeliner passes or to check created schedule for specific initiation interval. Patch by Alexey Lapshin. llvm-svn: 350414
* [CodeGen] Generate llvm.loop.parallel_accesses instead of ↵Michael Kruse2018-12-201-16/+24
| | | | | | | | | | | | | | llvm.mem.parallel_loop_access metadata. Instead of generating llvm.mem.parallel_loop_access metadata, generate llvm.access.group on instructions and llvm.loop.parallel_accesses on loops. There is one access group per generated loop. This is clang part of D52116/r349725. Differential Revision: https://reviews.llvm.org/D52117 llvm-svn: 349823
* Move LoopHint.h from Sema to ParseRichard Trieu2018-11-281-1/+0
| | | | | | | | struct LoopHint was only used within Parse and not in any of the Sema or Codegen files. In the non-Parse files where it was included, it either wasn't used or LoopHintAttr was used, so its inclusion did nothing. llvm-svn: 347728
* [TI removal] Test predicate rather than casting to detect a terminatorChandler Carruth2018-10-181-4/+5
| | | | | | and use the range based successor API. llvm-svn: 344730
* [CodeGen] Emit parallel_loop_access for each loop in the loop stack.Michael Kruse2018-08-031-2/+13
| | | | | | | | | | | | | | | | | Summary: Emit !llvm.mem.parallel_loop_access metadata for memory accesses even if the parallel loop is not the top on the loop stack. Fixes llvm.org/PR37558. Reviewers: ABataev, hfinkel, amusman, tyler.nowicki Reviewed By: hfinkel Subscribers: Meinersbur, hfinkel, cfe-commits Differential Revision: https://reviews.llvm.org/D48808 llvm-svn: 338810
* [UnrollAndJam] Add unroll_and_jam pragma handlingDavid Green2018-08-011-5/+49
| | | | | | | | | | | | | | This adds support for the unroll_and_jam pragma, to go with the recently added unroll and jam pass. The name of the pragma is the same as is used in the Intel compiler, and most of the code works the same as for unroll. #pragma clang loop unroll_and_jam has been separated into a different patch. This part adds #pragma unroll_and_jam with an optional count, and #pragma no_unroll_and_jam to disable the transform. Differential Revision: https://reviews.llvm.org/D47267 llvm-svn: 338566
* Remove trailing spaceFangrui Song2018-07-301-1/+1
| | | | | | sed -Ei 's/[[:space:]]+$//' include/**/*.{def,h,td} lib/**/*.{cpp,h} llvm-svn: 338291
* [CodeGen] Pass objects that are expensive to copy by const ref.Benjamin Kramer2016-11-241-5/+7
| | | | | | | No functionality change. Found by clang-tidy's performance-unnecessary-value-param. llvm-svn: 287894
* Add the loop end location to the loop metadata. This additional informationAmara Emerson2016-11-101-11/+17
| | | | | | | | | | | | can be used to improve the locations when generating remarks for loops. Depends on the companion LLVM change r286227. Patch by Florian Hahn. Differential Revision: https://reviews.llvm.org/D25764 llvm-svn: 286456
* [Pragma] Clear loop distribution attribute between loopsAdam Nemet2016-08-241-0/+1
| | | | llvm-svn: 279608
* Add loop pragma for Loop DistributionAdam Nemet2016-06-141-1/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: This is similar to other loop pragmas like 'vectorize'. Currently it only has state values: distribute(enable) and distribute(disable). When one of these is specified the corresponding loop metadata is generated: !{!"llvm.loop.distribute.enable", i1 true/false} As a result, loop distribution will be attempted on the loop even if Loop Distribution in not enabled globally. Analogously, with 'disable' distribution can be turned off for an individual loop even when the pass is otherwise enabled. There are some slight differences compared to the existing loop pragmas. 1. There is no 'assume_safety' variant which makes its handling slightly different from 'vectorize'/'interleave'. 2. Unlike the existing loop pragmas, it does not have a corresponding numeric pragma like 'vectorize' -> 'vectorize_width'. So for the consistency checks in CheckForIncompatibleAttributes we don't need to check it against other pragmas. We just need to check for duplicates of the same pragma. Reviewers: rsmith, dexonsmith, aaron.ballman Subscribers: bob.wilson, cfe-commits, hfinkel Differential Revision: http://reviews.llvm.org/D19403 llvm-svn: 272656
* Add a loop's debug location to its llvm.loop metadataHal Finkel2016-05-251-8/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Getting accurate locations for loops is important, because those locations are used by the frontend to generate optimization remarks. Currently, optimization remarks for loops often appear on the wrong line, often the first line of the loop body instead of the loop itself. This is confusing because that line might itself be another loop, or might be somewhere else completely if the body was an inlined function call. This happens because of the way we find the loop's starting location. First, we look for a preheader, and if we find one, and its terminator has a debug location, then we use that. Otherwise, we look for a location on an instruction in the loop header. The fallback heuristic is not bad, but will almost always find the beginning of the body, and not the loop statement itself. The preheader location search often fails because there's often not a preheader, and even when there is a preheader, depending on how it was formed, it sometimes carries the location of some preceeding code. I don't see any good theoretical way to fix this problem. On the other hand, this seems like a straightforward solution: Put the debug location in the loop's llvm.loop metadata. When emitting debug information, this commit causes us to add the debug location as an operand to each loop's llvm.loop metadata. Thus, we now generate this metadata for all loops (not just loops with optimization hints) when we're otherwise generating debug information. The remark test case changes depend on the companion LLVM commit r270771. llvm-svn: 270772
* CGLoopInfo: Use the MD_loop metadata kind from r264371, NFCDuncan P. N. Exon Smith2016-03-251-1/+1
| | | | | | | Besides a small compile-time speedup, there should be no real functionality change here. llvm-svn: 264372
* [OpenCL] Generate metadata for opencl_unroll_hint attributeAnastasia Stulova2016-02-191-8/+29
| | | | | | | | | | | | | | | Add support for opencl_unroll_hint attribute from OpenCL v2.0 s6.11.5. Reusing most of metadata generation from CGLoopInfo helper class. The code is based on Khronos OpenCL compiler: https://github.com/KhronosGroup/SPIR/tree/spirv-1.0 Patch by Liu Yaxun (Sam)! Differential Revision: http://reviews.llvm.org/D16686 llvm-svn: 261350
* Add new llvm.loop.unroll.enable metadata for use with "#pragma unroll".Mark Heffernan2015-08-101-12/+26
| | | | | | | | | | | | | | | | | | | | | | This change adds the new unroll metadata "llvm.loop.unroll.enable" which directs the optimizer to unroll a loop fully if the trip count is known at compile time, and unroll partially if the trip count is not known at compile time. This differs from "llvm.loop.unroll.full" which explicitly does not unroll a loop if the trip count is not known at compile time With this change "#pragma unroll" generates "llvm.loop.unroll.enable" rather than "llvm.loop.unroll.full" metadata. This changes the semantics of "#pragma unroll" slightly to mean "unroll aggressively (fully or partially)" rather than "unroll fully or not at all". The motivating example for this change was some internal code with a loop marked with "#pragma unroll" which only sometimes had a compile-time trip count depending on template magic. When the trip count was a compile-time constant, everything works as expected and the loop is fully unrolled. However, when the trip count was not a compile-time constant the "#pragma unroll" explicitly disabled unrolling of the loop(!). Removing "#pragma unroll" caused the loop to be unrolled partially which was desirable from a performance perspective. llvm-svn: 244467
* Use CGLoopInfo to emit metadata for loop hint pragmas.Tyler Nowicki2015-07-271-16/+113
| | | | | | | | When ‘#pragma clang loop vectorize(assume_safety)’ was specified on a loop other loop hints were lost. The problem is that CGLoopInfo attaches metadata differently than EmitCondBrHints in CGStmt. For do-loops CGLoopInfo attaches metadata to the br in the body block and for while and for loops, the inc block. EmitCondBrHints on the other hand always attaches data to the br in the cond block. When specifying assume_safety CGLoopInfo emits an empty llvm.loop metadata shadowing the metadata in the cond block. Loop transformations like rotate and unswitch would then eliminate the cond block and its non-empty metadata. This patch unifies both approaches for adding metadata and modifies the existing safety tests to include non-assume_safety loop hints. llvm-svn: 243315
* Make the variable names match the name of the metadata they control.Tyler Nowicki2015-07-141-21/+20
| | | | | | Rename Vectorizer to Vectorize and VectorizeUnroll to InterleaveCount. llvm-svn: 242241
* [IRGen] Fix the MSVC2013 buildDavid Majnemer2015-06-121-1/+2
| | | | llvm-svn: 239576
* Add assume_safety option for pragma loop vectorize and interleave.Tyler Nowicki2015-06-111-1/+29
| | | | | | | | Specifying #pragma clang loop vectorize(assume_safety) on a loop adds the mem.parallel_loop_access metadata to each load/store operation in the loop. This metadata tells loop access analysis (LAA) to skip memory dependency checking. llvm-svn: 239572
* Eliminate unnecessary namespace to prevent conflicts.Tyler Nowicki2015-06-081-2/+1
| | | | llvm-svn: 239365
* CodeGen: Update LoopAttributes for LLVM API changeDuncan P. N. Exon Smith2015-01-191-3/+2
| | | | | | `MDNode::getTemporary()` returns a `unique_ptr<>` as of r226504. llvm-svn: 226505
* IR: Update clang for Metadata/Value split in r223802Duncan P. N. Exon Smith2014-12-091-14/+13
| | | | | | Match LLVM API changes from r223802. llvm-svn: 223803
* Rename metadata llvm.loop.vectorize.unroll to llvm.loop.vectorize.interleave.Mark Heffernan2014-07-211-1/+1
| | | | llvm-svn: 213587
* Rename loop unrolling and loop vectorizer metadata to have a common prefix.Eli Bendersky2014-06-251-3/+3
| | | | | | | | | | | | | | | | | | | [Clang part] These patches rename the loop unrolling and loop vectorizer metadata such that they have a common 'llvm.loop.' prefix. Metadata name changes: llvm.vectorizer.* => llvm.loop.vectorizer.* llvm.loopunroll.* => llvm.loop.unroll.* This was a suggestion from an earlier review (http://reviews.llvm.org/D4090) which added the loop unrolling metadata. Patch by Mark Heffernan. llvm-svn: 211712
* This patch adds a helper class (CGLoopInfo) for marking memory instructions ↵Alexander Musman2014-05-221-0/+112
with llvm.mem.parallel_loop_access metadata. It also adds a simple initial version of codegen for pragma omp simd (it will change in the future to support all the clauses). Differential revision: http://reviews.llvm.org/D3644 llvm-svn: 209411
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