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* [CallSite removal] Move the legacy PM, call graph, and some inlinerChandler Carruth2019-04-191-7/+7
| | | | | | | | | | | | code to `CallBase`. This patch focuses on the legacy PM, call graph, and some of inliner and legacy passes interacting with those APIs from `CallSite` to the new `CallBase` class. No interesting changes. Differential Revision: https://reviews.llvm.org/D60412 llvm-svn: 358739
* [LoopUnroll] Move list of params into a struct [NFCI].Alina Sbirlea2019-04-182-63/+65
| | | | | | | | | | | | | | Summary: Cleanup suggested in review of r358304. Reviewers: sanjoy, efriedma Subscribers: jlebar, zzheng, dmgreen, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D60638 llvm-svn: 358723
* 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
* [CodeExtractor] Add a few debug lines to understand why a region is not ↵Quentin Colombet2019-04-161-3/+8
| | | | | | | | | | | | | | | | | | extracted The CodeExtractor is not smart enough to compute which basic block is the entry of a region. Instead it relies on the order of the list of basic blocks that is handed to it and assumes that the entry is the first block in the list. Without the additional debug information, it is hard to understand why a valid region does not get extracted, because we would miss that the order of in the list just doesn't match what the CodeExtractor wants. NFC llvm-svn: 358471
* [DEBUGINFO] Prevent Instcombine from dropping debuginfo when removing zextsWolfgang Pieb2019-04-151-5/+4
| | | | | | | | | | | Zexts can be treated like no-op casts when it comes to assessing whether their removal affects debug info. Reviewer: aprantl Differential Revision: https://reviews.llvm.org/D60641 llvm-svn: 358431
* [PGO] Profile guided code size optimization.Hiroshi Yamauchi2019-04-153-2/+46
| | | | | | | | | | | | | | | | | | | | | | | | | Summary: Enable some of the existing size optimizations for cold code under PGO. A ~5% code size saving in big internal app under PGO. The way it gets BFI/PSI is discussed in the RFC thread http://lists.llvm.org/pipermail/llvm-dev/2019-March/130894.html Note it doesn't currently touch loop passes. Reviewers: davidxl, eraman Reviewed By: eraman Subscribers: mgorny, javed.absar, smeenai, mehdi_amini, eraman, zzheng, steven_wu, dexonsmith, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D59514 llvm-svn: 358422
* [Transforms][ASan] Move findAllocaForValue() to Utils/Local.cpp. NFCAlexander Potapenko2019-04-151-0/+38
| | | | | | | | | | | | | | | | Summary: Factor out findAllocaForValue() from ASan so that we can use it in MSan to handle lifetime intrinsics. Reviewers: eugenis, pcc Subscribers: hiraditya, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D60615 llvm-svn: 358380
* [Mem2Reg] Delete unused PointerAllocaValuesFangrui Song2019-04-141-5/+0
| | | | | | It is unused after AliasSetTracker support was removed. llvm-svn: 358352
* [Mem2Reg] Simplify and micro optimizeFangrui Song2019-04-141-13/+9
| | | | | | | | * Rearrange continu/break * BBNumbers.lookup(A) -> BBNumbers.find(A)->second BBNumbers has been computed, thus we can assume the value exists in the predicate. llvm-svn: 358351
* [Mem2Reg] Don't call LBI.deleteValue on AllocInst/DbgVariableIntrinsicFangrui Song2019-04-141-6/+1
| | | | | | Only StoreInst/LoadInst are assigned numbers. Other types of instructions are not in LBI. llvm-svn: 358350
* [Mem2Reg] Simplify rewriteSingleStoreAllocaFangrui Song2019-04-141-5/+2
| | | | llvm-svn: 358349
* [Mem2Reg] Delete unused AllocaPointerValFangrui Song2019-04-131-4/+0
| | | | | | It is no longer used after the AliasSetTracker updating logic was removed. llvm-svn: 358334
* [SCEV] Add option to forget everything in SCEV.Alina Sbirlea2019-04-123-14/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: Create a method to forget everything in SCEV. Add a cl::opt and PassManagerBuilder option to use this in LoopUnroll. Motivation: Certain Halide applications spend a very long time compiling in forgetLoop, and prefer to forget everything and rebuild SCEV from scratch. Sample difference in compile time reduction: 21.04 to 14.78 using current ToT release build. Testcase showcasing this cannot be opensourced and is fairly large. The option disabled by default, but it may be desirable to enable by default. Evidence in favor (two difference runs on different days/ToT state): File Before (s) After (s) clang-9.bc 7267.91 6639.14 llvm-as.bc 194.12 194.12 llvm-dis.bc 62.50 62.50 opt.bc 1855.85 1857.53 File Before (s) After (s) clang-9.bc 8588.70 7812.83 llvm-as.bc 196.20 194.78 llvm-dis.bc 61.55 61.97 opt.bc 1739.78 1886.26 Reviewers: sanjoy Subscribers: mehdi_amini, jlebar, zzheng, javed.absar, dmgreen, jdoerfert, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D60144 llvm-svn: 358304
* Use llvm::lower_bound. NFCFangrui Song2019-04-122-11/+8
| | | | | | This reapplies rL358161. That commit inadvertently reverted an exegesis file to an old version. llvm-svn: 358246
* Revert "Use llvm::lower_bound. NFC"Ali Tamur2019-04-112-8/+11
| | | | | | | | | This reverts commit rL358161. This patch have broken the test: llvm/test/tools/llvm-exegesis/X86/uops-CMOV16rm-noreg.s llvm-svn: 358199
* Use llvm::lower_bound. NFCFangrui Song2019-04-112-11/+8
| | | | llvm-svn: 358161
* Change some dyn_cast to more apropriate isa. NFCFangrui Song2019-04-052-4/+4
| | | | llvm-svn: 357773
* [IR] Refactor attribute methods in Function class (NFC)Evandro Menezes2019-04-041-1/+1
| | | | | | | | Rename the functions that query the optimization kind attributes. Differential revision: https://reviews.llvm.org/D60287 llvm-svn: 357731
* 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
* [WebAssembly] Add Emscripten OS definition + small_printfAlon Zakai2019-04-031-0/+48
| | | | | | | | | | | | | | | The Emscripten OS provides a definition of __EMSCRIPTEN__, and also that it supports iprintf optimizations. Also define small_printf optimizations, which is a printf with float support but not long double (which in wasm can be useful since long doubles are 128 bit and force linking of float128 emulation code). This part is based on sunfish's https://reviews.llvm.org/D57620 (which can't land yet since the WASI integration isn't ready yet). Differential Revision: https://reviews.llvm.org/D60167 llvm-svn: 357552
* [SimplifyCFG] Don't split musttail call from retJoseph Tremoulet2019-04-021-1/+1
| | | | | | | | | | | | | | | | | | | Summary: When inserting an `unreachable` after a noreturn call, we must ensure that it's not a musttail call to avoid breaking the IR invariants for musttail calls. Reviewers: fedor.sergeev, majnemer Reviewed By: majnemer Subscribers: hiraditya, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D60080 llvm-svn: 357485
* [Transforms] Redundant getValueOperand (NFC)Brian Gesiak2019-04-021-2/+2
| | | | | | | | | `StoreInst::getValueOperand` is identical to `getOperand(0)`, so the call to `getOperand(0)` can be replaced. Further, `SI->getValueOperand` is redundantly called just a few lines down, despite its return value being stored in variable `DV`. No functional change. llvm-svn: 357479
* 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
* [LowerSwitch] Use ConstantRange::fromKnownBits(); NFCNikita Popov2019-03-231-9/+3
| | | | | | | Using an unsigned range to stay NFC, but a signed range would really be more useful here. llvm-svn: 356831
* [DebugInfo] Introduce DW_OP_LLVM_convertMarkus Lavin2019-03-191-15/+4
| | | | | | | | | | | | | | | | | | | | | Introduce a DW_OP_LLVM_convert Dwarf expression pseudo op that allows for a convenient way to perform type conversions on the Dwarf expression stack. As an additional bonus it paves the way for using other Dwarf v5 ops that need to reference a base_type. The new DW_OP_LLVM_convert is used from lib/Transforms/Utils/Local.cpp to perform sext/zext on debug values but mainly the patch is about preparing terrain for adding other Dwarf v5 ops that need to reference a base_type. For Dwarf v5 the op maps to DW_OP_convert and for earlier versions a complex shift & mask pattern is generated to emulate sext/zext. This is a recommit of r356442 with trivial fixes for the failing tests. Differential Revision: https://reviews.llvm.org/D56587 llvm-svn: 356451
* Revert "[DebugInfo] Introduce DW_OP_LLVM_convert"Markus Lavin2019-03-191-4/+15
| | | | | | | | | | | | | This reverts commit 1cf4b593a7ebd666fc6775f3bd38196e8e65fafe. Build bots found failing tests not detected locally. Failing Tests (3): LLVM :: DebugInfo/Generic/convert-debugloc.ll LLVM :: DebugInfo/Generic/convert-inlined.ll LLVM :: DebugInfo/Generic/convert-linked.ll llvm-svn: 356444
* [DebugInfo] Introduce DW_OP_LLVM_convertMarkus Lavin2019-03-191-15/+4
| | | | | | | | | | | | | | | | | | | Introduce a DW_OP_LLVM_convert Dwarf expression pseudo op that allows for a convenient way to perform type conversions on the Dwarf expression stack. As an additional bonus it paves the way for using other Dwarf v5 ops that need to reference a base_type. The new DW_OP_LLVM_convert is used from lib/Transforms/Utils/Local.cpp to perform sext/zext on debug values but mainly the patch is about preparing terrain for adding other Dwarf v5 ops that need to reference a base_type. For Dwarf v5 the op maps to DW_OP_convert and for earlier versions a complex shift & mask pattern is generated to emulate sext/zext. Differential Revision: https://reviews.llvm.org/D56587 llvm-svn: 356442
* [LLVM-C] Expose the "Add Discriminators" Pass To LLVM-CRobert Widmann2019-03-151-0/+3
| | | | | | | | | | | | | | | | Summary: Add bindings to create a wrapped "Add Discriminators" pass. Now that we have debug info support, this is a handy transform to have. Reviewers: whitequark, deadalnix Reviewed By: whitequark Subscribers: dblaikie, aprantl, hiraditya, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D58624 llvm-svn: 356272
* IR: Add immarg attributeMatt Arsenault2019-03-121-0/+1
| | | | | | | | | | | | | | | | | This indicates an intrinsic parameter is required to be a constant, and should not be replaced with a non-constant value. Add the attribute to all AMDGPU and generic intrinsics that comments indicate it should apply to. I scanned other target intrinsics, but I don't see any obvious comments indicating which arguments are intended to be only immediates. This breaks one questionable testcase for the autoupgrade. I'm unclear on whether the autoupgrade is supposed to really handle declarations which were never valid. The verifier fails because the attributes now refer to a parameter past the end of the argument list. llvm-svn: 355981
* [SanitizerCoverage] Avoid splitting critical edges when destination is a ↵Craig Topper2019-03-121-0/+4
| | | | | | | | | | | | basic block containing unreachable This patch adds a new option to SplitAllCriticalEdges and uses it to avoid splitting critical edges when the destination basic block ends with unreachable. Otherwise if we split the critical edge, sanitizer coverage will instrument the new block that gets inserted for the split. But since this block itself shouldn't be reachable this is pointless. These basic blocks will stick around and generate assembly, but they don't end in sane control flow and might get placed at the end of the function. This makes it look like one function has code that flows into the next function. This showed up while compiling the linux kernel with clang. The kernel has a tool called objtool that detected the code that appeared to flow from one function to the next. https://github.com/ClangBuiltLinux/linux/issues/351#issuecomment-461698884 Differential Revision: https://reviews.llvm.org/D57982 llvm-svn: 355947
* [SimplifyLibCalls] Simplify optimizePutsFangrui Song2019-03-121-10/+6
| | | | | | | | | | | The code might intend to replace puts("") with putchar('\n') even if the return value is used. It failed because use_empty() was used to guard the whole block. While returning '\n' (putchar('\n')) is technically correct (puts is only required to return a nonnegative number on success), doing this looks weird and there is really little benefit to optimize puts whose return value is used. So don't do that. llvm-svn: 355921
* [SimplifyLibCalls] Fix comments about fputs, memchr, and s[n]printf. NFCFangrui Song2019-03-121-5/+7
| | | | llvm-svn: 355905
* Reland "Relax constraints for reduction vectorization"Sanjoy Das2019-03-121-20/+26
| | | | | | | | | | | | | | | | | | | | | Change from original commit: move test (that uses an X86 triple) into the X86 subdirectory. Original description: Gating vectorizing reductions on *all* fastmath flags seems unnecessary; `reassoc` should be sufficient. Reviewers: tvvikram, mkuper, kristof.beyls, sdesmalen, Ayal Reviewed By: sdesmalen Subscribers: dcaballe, huntergr, jmolloy, mcrosier, jlebar, bixia, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D57728 llvm-svn: 355889
* Revert "Relax constraints for reduction vectorization"Sanjoy Das2019-03-111-26/+20
| | | | | | This reverts commit r355868. Breaks hexagon. llvm-svn: 355873
* Relax constraints for reduction vectorizationSanjoy Das2019-03-111-20/+26
| | | | | | | | | | | | | | | | | | Summary: Gating vectorizing reductions on *all* fastmath flags seems unnecessary; `reassoc` should be sufficient. Reviewers: tvvikram, mkuper, kristof.beyls, sdesmalen, Ayal Reviewed By: sdesmalen Subscribers: dcaballe, huntergr, jmolloy, mcrosier, jlebar, bixia, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D57728 llvm-svn: 355868
* [Utils] Extract EliminateUnreachableBlocks (NFC)Brian Gesiak2019-03-111-0/+22
| | | | | | | | | | | | | | | | | | | | | | | | | Summary: Extract the functionality of eliminating unreachable basic blocks within a function, previously encapsulated within the -unreachableblockelim pass, and make it available as a function within BlockUtils.h. No functional change intended other than making the logic reusable. Exposing this logic makes it easier to implement https://reviews.llvm.org/D59068, which fixes coroutines bug https://bugs.llvm.org/show_bug.cgi?id=40979. Reviewers: mkazantsev, wmi, davidxl, silvas, davide Reviewed By: davide Subscribers: llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D59069 llvm-svn: 355846
* [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
* [SelectionDAG] Allow the user to specify a memeq function.Clement Courbet2019-03-082-23/+49
| | | | | | | | | | | | | | | | | | | | | | | Summary: Right now, when we encounter a string equality check, e.g. `if (memcmp(a, b, s) == 0)`, we try to expand to a comparison if `s` is a small compile-time constant, and fall back on calling `memcmp()` else. This is sub-optimal because memcmp has to compute much more than equality. This patch replaces `memcmp(a, b, s) == 0` by `bcmp(a, b, s) == 0` on platforms that support `bcmp`. `bcmp` can be made much more efficient than `memcmp` because equality compare is trivially parallel while lexicographic ordering has a chain dependency. Subscribers: fedor.sergeev, jyknight, ckennelly, gchatelet, llvm-commits Differential Revision: https://reviews.llvm.org/D56593 llvm-svn: 355672
* [LoopRotate] fix crash encountered with callbrNick Desaulniers2019-03-061-3/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | Summary: While implementing inlining support for callbr (https://bugs.llvm.org/show_bug.cgi?id=40722), I hit a crash in Loop Rotation when trying to build the entire x86 Linux kernel (drivers/char/random.c). This is a small fix up to r353563. Test case is drivers/char/random.c (with callbr's inlined), then ran through creduce, then `opt -opt-bisect-limit=<limit>`, then bugpoint. Thanks to Craig Topper for immediately spotting the fix, and teaching me how to fish. Reviewers: craig.topper, jyknight Reviewed By: craig.topper Subscribers: hiraditya, llvm-commits, srhines Tags: #llvm Differential Revision: https://reviews.llvm.org/D58929 llvm-svn: 355564
* Make MergeBlockIntoPredecessor conformant to the precondition of calling ↵Chijun Sima2019-02-281-1/+3
| | | | | | | | | | | | | | | | | | | | | DTU.applyUpdates Summary: It is mentioned in the document of DTU that "It is illegal to submit any update that has already been submitted, i.e., you are supposed not to insert an existent edge or delete a nonexistent edge." It is dangerous to violet this rule because DomTree and PostDomTree occasionally crash on this scenario. This patch fixes `MergeBlockIntoPredecessor`, making it conformant to this precondition. Reviewers: kuhar, brzycki, chandlerc Reviewed By: brzycki Subscribers: hiraditya, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D58444 llvm-svn: 355105
* BreakCriticalEdges: Update PostDominatorTreeMatt Arsenault2019-02-221-4/+13
| | | | llvm-svn: 354673
* [LowerSwitch][AMDGPU] Do not handle impossible valuesRoman Tereshin2019-02-221-68/+137
| | | | | | | | | | | | This patch adds LazyValueInfo to LowerSwitch to compute the range of the value being switched over and reduce the size of the tree LowerSwitch builds to lower a switch. Reviewed By: arsenm Differential Revision: https://reviews.llvm.org/D58096 llvm-svn: 354670
* [DTU] Refine the interface and logic of applyUpdatesChijun Sima2019-02-222-20/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 Sima2019-02-223-11/+16
| | | | | | | | | | | | | | | | 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
* [MemorySSA & LoopPassManager] Update MemorySSA in formDedicatedExitBlocks.Alina Sbirlea2019-02-213-5/+7
| | | | | | | MemorySSA is now updated when forming dedicated exit blocks. Resolves PR40037. llvm-svn: 354623
* [GVN] Small tweaks to comments, style, and missed vector handlingPhilip Reames2019-02-201-5/+5
| | | | | | Noticed these while doing a final sweep of the code to make sure I hadn't missed anything in my last couple of patches. The (minor) missed optimization was noticed because of the stylistic fix to avoid an overly specific cast. llvm-svn: 354412
* [GVN] Fix last crasher w/non-integral pointersPhilip Reames2019-02-201-2/+18
| | | | | | | | | | Same case as for memset and memcpy, but this time for clobbering stores and loads. We still can't allow coercion to or from non-integrals, regardless of the transform. Now that I'm done the whole little sequence, it seems apparent that we'd entirely missed reasoning about clobbers in the original GVN support for non-integral pointers. My appologies, I thought we'd upstreamed all of this, but it turns out we were still carrying a downstream hack which hid all of these issues. My chanks to Cherry Zhang for helping debug. llvm-svn: 354407
* [GVN] Fix a crash bug w/non-integral pointers and memtransfersPhilip Reames2019-02-191-0/+5
| | | | | | Problem is very similiar to the one fixed for memsets in r354399, we try to coerce a value to non-integral type, and then crash while try to do so. Since we shouldn't be doing such coercions to start with, easy fix. From inspection, I see two other cases which look to be similiar and will follow up with most test cases and fixes if confirmed. llvm-svn: 354403
* [GVN] Fix a non-integral pointer bug w/vector typesPhilip Reames2019-02-191-2/+2
| | | | | | GVN generally doesn't forward structs or array types, but it *will* forward vector types to non-vectors and vice versa. As demonstrated in tests, we need to inhibit the same set of transforms for vector of non-integral pointers as for non-integral pointers themselves. llvm-svn: 354401
* [GVN] Fix a crash bug around non-integral pointersPhilip Reames2019-02-191-3/+16
| | | | | | If we encountered a location where we tried to forward the value of a memset to a load of a non-integral pointer, we crashed. Such a forward is not legal in general, but we can forward null pointers. Test for both cases are included. llvm-svn: 354399
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