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2025-09-29Reland "[DebugInfo][DwarfDebug] Separate creation and population of abstract ↵Vladislav Dzhidzhoev
subprogram DIEs" (#160786) This is an attempt to reland https://github.com/llvm/llvm-project/pull/159104 with the fix for https://github.com/llvm/llvm-project/issues/160197. The original patch had the following problem: when an abstract subprogram DIE is constructed from within `DwarfDebug::endFunctionImpl()`, `DwarfDebug::constructAbstractSubprogramScopeDIE()` acknowledges `unit:` field of DISubprogram. But an abstract subprogram DIE constructed from `DwarfDebug::beginModule()` was put in the same compile unit to which global variable referencing the subprogram belonged, regardless of subprogram's `unit:`. This is fixed by adding `DwarfDebug::getOrCreateAbstractSubprogramCU()` used by both`DwarfDebug:: constructAbstractSubprogramScopeDIE()` and `DwarfCompileUnit::getOrCreateSubprogramDIE()` when abstract subprogram is queried during the creation of DIEs for globals in `DwarfDebug::beginModule()`. The fix and the already-reviewed code from https://github.com/llvm/llvm-project/pull/159104 are two separate commits in this PR. ===== The original commit message follows: With this change, construction of abstract subprogram DIEs is split in two stages/functions: creation of DIE (in DwarfCompileUnit::getOrCreateAbstractSubprogramDIE) and its population with children (in DwarfCompileUnit::constructAbstractSubprogramScopeDIE). With that, abstract subprograms can be created/referenced from DwarfDebug::beginModule, which should solve the issue with static local variables DIE creation of inlined functons with optimized-out definitions. It fixes https://github.com/llvm/llvm-project/issues/29985. LexicalScopes class now stores mapping from DISubprograms to their corresponding llvm::Function's. It is supposed to be built before processing of each function (so, now LexicalScopes class has a method for "module initialization" alongside the method for "function initialization"). It is used by DwarfCompileUnit to determine whether a DISubprogram needs an abstract DIE before DwarfDebug::beginFunction is invoked. DwarfCompileUnit::getOrCreateSubprogramDIE method is added, which can create an abstract or a concrete DIE for a subprogram. It accepts llvm::Function* argument to determine whether a concrete DIE must be created. This is a temporary fix for https://github.com/llvm/llvm-project/issues/29985. Ideally, it will be fixed by moving global variables and types emission to DwarfDebug::endModule (https://reviews.llvm.org/D144007, https://reviews.llvm.org/D144005). Some code proposed by Ellis Hoag <ellis.sparky.hoag@gmail.com> in https://github.com/llvm/llvm-project/pull/90523 was taken for this commit.
2025-09-23Revert "[DebugInfo][DwarfDebug] Separate creation and population of abstract ↵Vladislav Dzhidzhoev
subprogram DIEs" (#160349) Reverts llvm/llvm-project#159104 due to the issues reported in https://github.com/llvm/llvm-project/issues/160197.
2025-09-17[DebugInfo][DwarfDebug] Separate creation and population of abstract ↵Vladislav Dzhidzhoev
subprogram DIEs (#159104) With this change, construction of abstract subprogram DIEs is split in two stages/functions: creation of DIE (in DwarfCompileUnit::getOrCreateAbstractSubprogramDIE) and its population with children (in DwarfCompileUnit::constructAbstractSubprogramScopeDIE). With that, abstract subprograms can be created/referenced from DwarfDebug::beginModule, which should solve the issue with static local variables DIE creation of inlined functons with optimized-out definitions. It fixes https://github.com/llvm/llvm-project/issues/29985. LexicalScopes class now stores mapping from DISubprograms to their corresponding llvm::Function's. It is supposed to be built before processing of each function (so, now LexicalScopes class has a method for "module initialization" alongside the method for "function initialization"). It is used by DwarfCompileUnit to determine whether a DISubprogram needs an abstract DIE before DwarfDebug::beginFunction is invoked. DwarfCompileUnit::getOrCreateSubprogramDIE method is added, which can create an abstract or a concrete DIE for a subprogram. It accepts llvm::Function* argument to determine whether a concrete DIE must be created. This is a temporary fix for https://github.com/llvm/llvm-project/issues/29985. Ideally, it will be fixed by moving global variables and types emission to DwarfDebug::endModule (https://reviews.llvm.org/D144007, https://reviews.llvm.org/D144005). Some code proposed by Ellis Hoag <ellis.sparky.hoag@gmail.com> in https://github.com/llvm/llvm-project/pull/90523 was taken for this commit.
2025-06-02[llvm] Use *Set::insert_range (NFC) (#138237)Kazu Hirata
2024-06-26[CodeGen] Use range-based for loops (NFC) (#96777)Kazu Hirata
2021-04-19[CSSPGO] Exclude pseudo probes from slot indexHongtao Yu
Pseudo probe are currently given a slot index like other regular instructions. This affects register pressure and lifetime weight computation because of enlarged lifetime length with pseudo probe instructions. As a consequence, program could get different code generated w/ and w/o pseudo probes. I'm closing the gap by excluding pseudo probes from stack index and downstream register allocation related passes. Reviewed By: wmi Differential Revision: https://reviews.llvm.org/D100334
2021-01-08[Target, Transforms] Use *Set::contains (NFC)Kazu Hirata
2020-06-08[NFC] Fix quadratic LexicalScopes::constructScopeNestJan-Willem Maessen
We sometimes have functions with large numbers of sibling basic blocks (usually with an error path exit from each one). This was triggering the qudratic behavior in this function - after visiting each child llvm would re-scan the parent from the beginning again. We modify the work stack to record the next index to be worked on alongside the pointer. This avoids the need to linearly search for the next unfinished child. Differential Revision: https://reviews.llvm.org/D80029
2020-06-04[LiveDebugValues] Cache LexicalScopes::getMachineBasicBlocks, NFCIVedant Kumar
Summary: Cache the results from getMachineBasicBlocks in LexicalScopes to speed up UserValueScopes::dominates queries. This replaces the caching done in UserValueScopes. Compared to the old caching method, this reduces memory traffic when a VarLoc is copied (e.g. when a VarLocMap grows), and enables caching across basic blocks. When compiling sqlite 3.5.7 (CTMark version), this patch reduces the number of calls to getMachineBasicBlocks from 10,207 to 1,093. I also measured a small compile-time reduction (~ 0.1% of total wall time, on average, on my machine). As a drive-by, I made the DebugLoc in UserValueScopes a const reference to cut down on MetadataTracking traffic. Reviewers: jmorse, Orlando, aprantl, nikic Subscribers: hiraditya, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D80957
2020-02-28[DebugInfo] Re-implement LexicalScopes dominance method, add unit testsJeremy Morse
Way back in D24994, the combination of LexicalScopes::dominates and LiveDebugValues was identified as having worst-case quadratic complexity, but it wasn't triggered by any code path at the time. I've since run into a scenario where this occurs, in a very large basic block where large numbers of inlined DBG_VALUEs are present. The quadratic-ness comes from LiveDebugValues::join calling "dominates" on every variable location, and LexicalScopes::dominates potentially touching every instruction in a block to test for the presence of a scope. We have, however, already computed the presence of scopes in blocks, in the "InstrRanges" of each scope. This patch switches the dominates method to examine whether a block is present in a scope's InsnRanges, avoiding walking through the whole block. At the same time, fix getMachineBasicBlocks to account for the fact that InsnRanges can cover multiple blocks, and add some unit tests, as Lexical Scopes didn't have any. Differential revision: https://reviews.llvm.org/D73725
2019-10-19Prune two MachineInstr.h includes, fix up depsReid Kleckner
MachineInstr.h included AliasAnalysis.h, which includes a world of IR constructs mostly unneeded in CodeGen. Prune it. Same for DebugInfoMetadata.h. Noticed with -ftime-trace. llvm-svn: 375311
2019-01-19Update the file headers across all of the LLVM projects in the monorepoChandler Carruth
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
2018-04-30IWYU for llvm-config.h in llvm, additions.Nico Weber
See r331124 for how I made a list of files missing the include. I then ran this Python script: for f in open('filelist.txt'): f = f.strip() fl = open(f).readlines() found = False for i in xrange(len(fl)): p = '#include "llvm/' if not fl[i].startswith(p): continue if fl[i][len(p):] > 'Config': fl.insert(i, '#include "llvm/Config/llvm-config.h"\n') found = True break if not found: print 'not found', f else: open(f, 'w').write(''.join(fl)) and then looked through everything with `svn diff | diffstat -l | xargs -n 1000 gvim -p` and tried to fix include ordering and whatnot. No intended behavior change. llvm-svn: 331184
2017-12-15MachineFunction: Return reference from getFunction(); NFCMatthias Braun
The Function can never be nullptr so we can return a reference. llvm-svn: 320884
2017-10-15Reverting r315590; it did not include changes for llvm-tblgen, which is ↵Aaron Ballman
causing link errors for several people. Error LNK2019 unresolved external symbol "public: void __cdecl `anonymous namespace'::MatchableInfo::dump(void)const " (?dump@MatchableInfo@?A0xf4f1c304@@QEBAXXZ) referenced in function "public: void __cdecl `anonymous namespace'::AsmMatcherEmitter::run(class llvm::raw_ostream &)" (?run@AsmMatcherEmitter@?A0xf4f1c304@@QEAAXAEAVraw_ostream@llvm@@@Z) llvm-tblgen D:\llvm\2017\utils\TableGen\AsmMatcherEmitter.obj 1 llvm-svn: 315854
2017-10-12[dump] Remove NDEBUG from test to enable dump methods [NFC]Don Hinton
Summary: Add LLVM_FORCE_ENABLE_DUMP cmake option, and use it along with LLVM_ENABLE_ASSERTIONS to set LLVM_ENABLE_DUMP. Remove NDEBUG and only use LLVM_ENABLE_DUMP to enable dump methods. Move definition of LLVM_ENABLE_DUMP from config.h to llvm-config.h so it'll be picked up by public headers. Differential Revision: https://reviews.llvm.org/D38406 llvm-svn: 315590
2017-07-19Fixing an issue with the initialization of LexicalScopes objects when mixing ↵Wolfgang Pieb
debug and non-debug units. Patch by Andrea DiBiagio. Differential Revision: https://reviews.llvm.org/D35637 llvm-svn: 308513
2017-06-06Sort the remaining #include lines in include/... and lib/....Chandler Carruth
I did this a long time ago with a janky python script, but now clang-format has built-in support for this. I fed clang-format every line with a #include and let it re-sort things according to the precise LLVM rules for include ordering baked into clang-format these days. I've reverted a number of files where the results of sorting includes isn't healthy. Either places where we have legacy code relying on particular include ordering (where possible, I'll fix these separately) or where we have particular formatting around #include lines that I didn't want to disturb in this patch. This patch is *entirely* mechanical. If you get merge conflicts or anything, just ignore the changes in this patch and run clang-format over your #include lines in the files. Sorry for any noise here, but it is important to keep these things stable. I was seeing an increasing number of patches with irrelevant re-ordering of #include lines because clang-format was used. This patch at least isolates that churn, makes it easy to skip when resolving conflicts, and gets us to a clean baseline (again). llvm-svn: 304787
2017-05-22Don't generate line&scope debug info for meta-instructions.Adrian Prantl
MachineInstructions that don't generate any code (such as IMPLICIT_DEFs) should not generate any debug info either. Fixes PR33107. https://bugs.llvm.org/show_bug.cgi?id=33107 This reapplies r303566 without any modifications. The stage2 build failures persisted even after reverting this patch, and looking back through history, it looks like these tests are flaky. llvm-svn: 303575
2017-05-22Revert "Don't generate line&scope debug info for meta-instructions."Adrian Prantl
This reverts commit r303566 while investigating a stage2 buildbot failure. llvm-svn: 303570
2017-05-22Don't generate line&scope debug info for meta-instructions.Adrian Prantl
MachineInstructions that don't generate any code (such as IMPLICIT_DEFs) should not generate any debug info either. Fixes PR33107. https://bugs.llvm.org/show_bug.cgi?id=33107 llvm-svn: 303566
2017-02-17[CodeGen] Fix some Clang-tidy modernize and Include What You Use warnings; ↵Eugene Zelenko
other minor fixes (NFC). llvm-svn: 295499
2017-02-17Handle link of NoDebug CU with a CU that has debug emission enabledTeresa Johnson
Summary: This is an issue both with regular and Thin LTO. When we link together a DICompileUnit that is marked NoDebug (e.g when compiling with -g0 but applying an AutoFDO profile, which requires location tracking in the compiler) and a DICompileUnit with debug emission enabled, we can have failures during dwarf debug generation. Specifically, when we have inlined from the NoDebug compile unit into the debug compile unit, we can fail during construction of the abstract and inlined scope DIEs. This is because the SPMap does not include NoDebug CUs (they are skipped in the debug_compile_units_iterator). This patch fixes the failures by skipping locations from NoDebug CUs when extracting lexical scopes. Reviewers: dblaikie, aprantl Subscribers: mehdi_amini, llvm-commits Differential Revision: https://reviews.llvm.org/D29765 llvm-svn: 295384
2017-02-14Reformat slightly.Eric Christopher
llvm-svn: 295096
2017-01-28Cleanup dump() functions.Matthias Braun
We had various variants of defining dump() functions in LLVM. Normalize them (this should just consistently implement the things discussed in http://lists.llvm.org/pipermail/cfe-dev/2014-January/034323.html For reference: - Public headers should just declare the dump() method but not use LLVM_DUMP_METHOD or #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP) - The definition of a dump method should look like this: #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP) LLVM_DUMP_METHOD void MyClass::dump() { // print stuff to dbgs()... } #endif llvm-svn: 293359
2016-09-28Rewrite loops to use range-based for. (NFC)Adrian Prantl
llvm-svn: 282608
2016-04-21Fixed Dwarf debug info emission to skip DILexicalBlockFile entries.Amjad Aboud
Before this fix, DILexicalBlockFile entries were skipped only in some cases and were not in other cases. Differential Revision: http://reviews.llvm.org/D18724 llvm-svn: 267004
2015-04-29IR: Give 'DI' prefix to debug info metadataDuncan P. N. Exon Smith
Finish off PR23080 by renaming the debug info IR constructs from `MD*` to `DI*`. The last of the `DIDescriptor` classes were deleted in r235356, and the last of the related typedefs removed in r235413, so this has all baked for about a week. Note: If you have out-of-tree code (like a frontend), I recommend that you get everything compiling and tests passing with the *previous* commit before updating to this one. It'll be easier to keep track of what code is using the `DIDescriptor` hierarchy and what you've already updated, and I think you're extremely unlikely to insert bugs. YMMV of course. Back to *this* commit: I did this using the rename-md-di-nodes.sh upgrade script I've attached to PR23080 (both code and testcases) and filtered through clang-format-diff.py. I edited the tests for test/Assembler/invalid-generic-debug-node-*.ll by hand since the columns were off-by-three. It should work on your out-of-tree testcases (and code, if you've followed the advice in the previous paragraph). Some of the tests are in badly named files now (e.g., test/Assembler/invalid-mdcompositetype-missing-tag.ll should be 'dicompositetype'); I'll come back and move the files in a follow-up commit. llvm-svn: 236120
2015-04-14DebugInfo: Gut DISubprogram and DILexicalBlock*Duncan P. N. Exon Smith
Gut the `DIDescriptor` wrappers around `MDLocalScope` subclasses. Note that `DILexicalBlock` wraps `MDLexicalBlockBase`, not `MDLexicalBlock`. llvm-svn: 234850
2015-04-06CodeGen: Stop using DIDescriptor::is*() and auto-castingDuncan P. N. Exon Smith
Same as r234255, but for lib/CodeGen and lib/Target. llvm-svn: 234258
2015-03-31DebugInfo: Remove LexicalBlockFile scope/context distinctionDuncan P. N. Exon Smith
Two things here: 1. I read `getScope()` and `getContext()` backwards in r233640. There was no need for `getScopeOfScope()`. Obviously not enough test coverage here (as I said in that commit, I'm going to come back to that), but anyway I'm reverting to the behaviour before r233640. 2. The callers that use `DILexicalBlockFile::getContext()` don't seem to care about the difference. Just have it redirect to `getScope()` so I can't get confused again. llvm-svn: 233650
2015-03-30LexicalScopes: Cleanup remaining uses of DebugLocDuncan P. N. Exon Smith
llvm-svn: 233644
2015-03-30DebugLoc: Remove getFromDILexicalBlock()Duncan P. N. Exon Smith
The only user of `DebugLoc::getFromDILexicalBlock()` was creating a new `MDLocation` as convenient API for passing an `MDScope`. Stop doing that, and remove the API. If in the future we actually *want* to create new DebugLocs, calling `MDLexicalBlock::get()` makes more sense. llvm-svn: 233643
2015-03-30LexicalScopes: Use debug info hierarchy pervasivelyDuncan P. N. Exon Smith
Pervasively use the types provided by the debug info hierarchy rather than `MDNode` in `LexicalScopes`. I noticed (again, I guess, based on comments in the implementation?) that `DILexicalBlockFile::getScope()` returns something different from `DILexicalBlockFile::getContext()`. I created a local helper for getting the same logic from `MDLexicalBlockFile` called `getScopeOfScope()`. I still don't really understand it, but I've added some FIXMEs and I'll come back to it (I suspect the way we encode these objects isn't really ideal). Note that my previous commit r233610 accidentally changed behaviour in `findLexicalScope()` -- it transitioned from a call to `DILexicalBlockFile::getScope()` to `MDLexicalBlockFile::getScope()` (sounds right, doesn't it?) -- so I've fixed that as a drive-by. No tests failed with my error, so it looks like we're missing some coverage here... when I come back to understand the logic, I'll see if I can add some. Other than the fix to `findLexicalScope()`, no functionality change. llvm-svn: 233640
2015-03-30LexicalScopes: Use MDLocation directly instead of DebugLocDuncan P. N. Exon Smith
There's no benefit to using `DebugLoc` here. Moreover, this will let a follow-up commit work with `MDScope` directly instead of `DebugLoc`. llvm-svn: 233610
2015-03-30CodeGen: Use the new DebugLoc API, NFCDuncan P. N. Exon Smith
Update lib/CodeGen (and lib/Target) to use the new `DebugLoc` API. llvm-svn: 233582
2015-02-17AsmPrinter: Stop creating DebugLocsDuncan P. N. Exon Smith
While looking at a heap profile of a clang LTO bootstrap with -g, I noticed that 2.2% of memory in an `llvm-lto` of clang is from calling `DebugLoc::get()` in `collectVariableInfo()` (accounting for ~40% of memory used for `MDLocation`s). I suspect this was introduced by r226736, whose goal was to prevent uniquing of `DebugLoc`s (goal achieved, if so). There's no reason we need a `DebugLoc` here at all -- it was just being used for (in)convenient API -- so the fix is to pass the scope and inlined-at directly to `LexicalScopes::findInlinedScope()`. llvm-svn: 229459
2015-02-16MSVC 2013 supports std::forward_as_tuple, while MSVC 2012 did not; so we can ↵Aaron Ballman
move to using the improved API. llvm-svn: 229414
2014-10-14DebugInfo: Ensure that all debug location scope chains from instructions ↵David Blaikie
within a function, lead to the function itself. Let me tell you a tale... Originally committed in r211723 after discovering a nasty case of weird scoping due to inlining, this was reverted in r211724 after it fired in ASan/compiler-rt. (minor diversion where I accidentally committed/reverted again in r211871/r211873) After further testing and fixing bugs in ArgumentPromotion (r211872) and Inlining (r212065) it was recommitted in r212085. Reverted in r212089 after the sanitizer buildbots still showed problems. Fixed another bug in ArgumentPromotion (r212128) found by this assertion. Recommitted in r212205, reverted in r212226 after it crashed some more on sanitizer buildbots. Fix clang some more in r212761. Recommitted in r212776, reverted in r212793. ASan failures. Recommitted in r213391, reverted in r213432, trying to reproduce flakey ASan build failure. Fixed bugs in r213805 (ArgPromo + DebugInfo), r213952 (LiveDebugVariables strips dbg_value intrinsics in functions not described by debug info). Recommitted in r214761, reverted in r214999, flakey failure on Windows buildbot. Fixed DeadArgElimination + DebugInfo bug in r219210. Recommitted in r219215, reverted in r219512, failure on ObjC++ atomic properties in the test-suite on Darwin. Fixed ObjC++ atomic properties issue in Clang in r219690. [This commit is provided 'as is' with no hope that this is the last time I commit this change either expressed or implied] llvm-svn: 219702
2014-10-14Revert "Fix stuff... again."David Blaikie
Accidental commit. This reverts commit r219693. llvm-svn: 219695
2014-10-14Fix stuff... again.David Blaikie
llvm-svn: 219693
2014-10-10Revert "DebugInfo: Ensure that all debug location scope chains from ↵David Blaikie
instructions within a function, lead to the function itself." This invariant is violated (& the assertions fire) on some Objective C++ in the test-suite. Reverting while I investigate. This reverts commit r219215. llvm-svn: 219523
2014-10-07DebugInfo: Ensure that all debug location scope chains from instructions ↵David Blaikie
within a function, lead to the function itself. Let me tell you a tale... Originally committed in r211723 after discovering a nasty case of weird scoping due to inlining, this was reverted in r211724 after it fired in ASan/compiler-rt. (minor diversion where I accidentally committed/reverted again in r211871/r211873) After further testing and fixing bugs in ArgumentPromotion (r211872) and Inlining (r212065) it was recommitted in r212085. Reverted in r212089 after the sanitizer buildbots still showed problems. Fixed another bug in ArgumentPromotion (r212128) found by this assertion. Recommitted in r212205, reverted in r212226 after it crashed some more on sanitizer buildbots. Fix clang some more in r212761. Recommitted in r212776, reverted in r212793. ASan failures. Recommitted in r213391, reverted in r213432, trying to reproduce flakey ASan build failure. Fixed bugs in r213805 (ArgPromo + DebugInfo), r213952 (LiveDebugVariables strips dbg_value intrinsics in functions not described by debug info). Recommitted in r214761, reverted in r214999, flakey failure on Windows buildbot. Fixed DeadArgElimination + DebugInfo bug in r219210. Recommitting and hoping that's the last of it. [That one burned down, fell over, then sank into the swamp.] llvm-svn: 219215
2014-08-21Repace SmallPtrSet with SmallPtrSetImpl in function arguments to avoid ↵Craig Topper
needing to mention the size. llvm-svn: 216158
2014-08-18Revert "Repace SmallPtrSet with SmallPtrSetImpl in function arguments to ↵Craig Topper
avoid needing to mention the size." Getting a weird buildbot failure that I need to investigate. llvm-svn: 215870
2014-08-17Repace SmallPtrSet with SmallPtrSetImpl in function arguments to avoid ↵Craig Topper
needing to mention the size. llvm-svn: 215868
2014-08-06Revert "Reapply "DebugInfo: Ensure that all debug location scope chains from ↵David Blaikie
instructions within a function, lead to the function itself."" This reverts commit r214761. Revert while Reid investigates & provides a reproduction for an assertion failure for this on Windows. llvm-svn: 214999
2014-08-04Reapply "DebugInfo: Ensure that all debug location scope chains from ↵David Blaikie
instructions within a function, lead to the function itself." Originally reverted in r213432 with flakey failures on an ASan self-host build. After reduction it seems to be the same issue fixed in r213805 (ArgPromo + DebugInfo: Handle updating debug info over multiple applications of argument promotion) and r213952 (by having LiveDebugVariables strip dbg_value intrinsics in functions that are not described by debug info). Though I cannot explain why this failure was flakey... llvm-svn: 214761
2014-07-18Revert "Reapply "DebugInfo: Ensure that all debug location scope chains from ↵Eric Christopher
instructions within a function, lead to the function itself."""" After a successful build it seems to have come back on a later build. This reverts commit r213391. llvm-svn: 213432
2014-07-18Reapply "DebugInfo: Ensure that all debug location scope chains from ↵David Blaikie
instructions within a function, lead to the function itself.""" Recommits 212776 which was reverted in r212793. This has been committed and recommitted a few times as I try to test it harder and find/fix more issues. The most recent revert was due to an asan bot failure which I can't seem to reproduce locally, though I believe I'm following all the steps the buildbot does. So I'm going to recommit this in the hopes of investigating the failure on the buildbot itself... apologies in advance for the bot noise. If anyone sees failures with this /please/ provide me with any reproductions, etc. llvm-svn: 213391