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2013-04-05Properly model precise lifetime when given an incomplete dataflow sequence.Michael Gottesman
The normal dataflow sequence in the ARC optimizer consists of the following states: Retain -> CanRelease -> Use -> Release The optimizer before this patch stored the uses that determine the lifetime of the retainable object pointer when it bottom up hits a retain or when top down it hits a release. This is correct for an imprecise lifetime scenario since what we are trying to do is remove retains/releases while making sure that no ``CanRelease'' (which is usually a call) deallocates the given pointer before we get to the ``Use'' (since that would cause a segfault). If we are considering the precise lifetime scenario though, this is not correct. In such a situation, we *DO* care about the previous sequence, but additionally, we wish to track the uses resulting from the following incomplete sequences: Retain -> CanRelease -> Release (TopDown) Retain <- Use <- Release (BottomUp) *NOTE* This patch looks large but the most of it consists of updating test cases. Additionally this fix exposed an additional bug. I removed the test case that expressed said bug and will recommit it with the fix in a little bit. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178921 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-05Tidy up a bit. No functional change.Jim Grosbach
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178915 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-05Disable the optimization about promoting vector-element-access with symbolic ↵Shuxin Yang
index. This optimization is unstable at this moment; it 1) block us on a very important application 2) PR15200 3) test6 and test7 in test/Transforms/ScalarRepl/dynamic-vector-gep.ll (the CHECK command compare the output against wrong result) I personally believe this optimization should not have any impact on the autovectorized code, as auto-vectorizer is supposed to put gather/scatter in a "right" way. Although in theory downstream optimizaters might reveal some gather/scatter optimization opportunities, the chance is quite slim. For the hand-crafted vectorizing code, in term of redundancy elimination, load-CSE, copy-propagation and DSE can collectively achieve the same result, but in much simpler way. On the other hand, these optimizers are able to improve the code in a incremental way; in contrast, SROA is sort of all-or-none approach. However, SROA might slighly win in stack size, as it tries to figure out a stretch of memory tightenly cover the area accessed by the dynamic index. rdar://13174884 PR15200 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178912 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-05Added two debug logging messages to VisitInstructionsTopDown to match ↵Michael Gottesman
VisitInstructionsBottomUp. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178895 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-05Cleaned up whitespace and made debug logging less verbose.Michael Gottesman
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178893 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-04LoopVectorizer: Pass OperandValueKind information to the cost modelArnold Schwaighofer
Pass down the fact that an operand is going to be a vector of constants. This should bring the performance of MultiSource/Benchmarks/PAQ8p/paq8p on x86 back. It had degraded to scalar performance due to my pervious shift cost change that made all shifts expensive on x86. radar://13576547 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178809 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-04Reassociate: Avoid iterator invalidation.Benjamin Kramer
OpndPtrs stored pointers into the Opnd vector that became invalid when the vector grows. Store indices instead. Sadly I only have a large testcase that only triggers under valgrind, so I didn't include it. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178793 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-03Refactored out the helper method FindPredecessorAutoreleaseWithSafePath from ↵Michael Gottesman
ObjCARCOpt::OptimizeReturns. Now ObjCARCOpt::OptimizeReturns is easy to read and reason about. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178715 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-03Refactored out the helper function FindPredecessorRetainWithSafePath from ↵Michael Gottesman
ObjCARCOpt::OptimizeReturns. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178714 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-03Small cleanups.Michael Gottesman
Cleaned up trailing whitespace and added extra slashes in front of a function level comment so that it follow the convention of having 3 slashes. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178712 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-03Refactored out a part of ObjCARCOpt::OptimizeReturns into its own method ↵Michael Gottesman
HasSafePathToPredecessorCall. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178710 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-03Removed an old comment.Michael Gottesman
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178709 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-03Clean up arc annotations by moving the top/bottom BB annotations into ↵Michael Gottesman
conditional macros that no-op in Release mode instead of #ifdef sections of the code. This is to follow the example of the DEBUG macro. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178705 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-03Remove an optimization where we were changing an objc_autorelease into an ↵Michael Gottesman
objc_autoreleaseReturnValue. The semantics of ARC implies that a pointer passed into an objc_autorelease must live until some point (potentially down the stack) where an autorelease pool is popped. On the other hand, an objc_autoreleaseReturnValue just signifies that the object must live until the end of the given function at least. Thus objc_autorelease is stronger than objc_autoreleaseReturnValue in terms of the semantics of ARC* implying that performing the given strength reduction without any knowledge of how this relates to the autorelease pool pop that is further up the stack violates the semantics of ARC. *Even though objc_autoreleaseReturnValue if you know that no RV optimization will occur is more computationally expensive. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178612 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-03Improved comment. No functionality change.Michael Gottesman
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178605 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-02Use a worklist to avoid a sneaky iterator invalidation.Bill Wendling
The iterator could be invalidated when it's recursively deleting a whole bunch of constant expressions in a constant initializer. Note: This was only reproducible if `opt' was run on a `.bc' file. If `opt' was run on a `.ll' file, it wouldn't crash. This is why the test first pushes the `.ll' file through `llvm-as' before feeding it to `opt'. PR15440 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178531 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-01Correct assertion conditionShuxin Yang
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178484 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-30Implement XOR reassociation. It is based on following rules:Shuxin Yang
rule 1: (x | c1) ^ c2 => (x & ~c1) ^ (c1^c2), only useful when c1=c2 rule 2: (x & c1) ^ (x & c2) = (x & (c1^c2)) rule 3: (x | c1) ^ (x | c2) = (x & c3) ^ c3 where c3 = c1 ^ c2 rule 4: (x | c1) ^ (x & c2) => (x & c3) ^ c1, where c3 = ~c1 ^ c2 It reduces an application's size (in terms of # of instructions) by 8.9%. Reviwed by Pete Cooper. Thanks a lot! rdar://13212115 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178409 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-29Add clang.arc.used to ModuleHasARC so ARC always runs if said call is ↵Michael Gottesman
present in a module. clang.arc.used is an interesting call for ARC since ObjCARCContract needs to run to remove said intrinsic to avoid a linker error (since the call does not exist). git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178369 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-29Removed trailing whitespace.Michael Gottesman
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178329 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-28Removed dead code from ObjCARCOpts relating to tracking objc_retainBlocks ↵Michael Gottesman
through the ARC Dataflow analysis. By the time we get to the ARC dataflow analysis, any objc_retainBlock calls are not optimizable. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178306 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-28Minor simplification.Bill Wendling
Go ahead and use the full path for both the .gcno and .gcda files. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178302 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-28Non optimizable objc_retainBlock calls are not forwarding.Michael Gottesman
Since we handle optimizable objc_retainBlocks through strength reduction in OptimizableIndividualCalls, we know that all code after that point will only see non-optimizable objc_retainBlock calls. IsForwarding is only called by functions after that point, so it is ok to just classify objc_retainBlock as non-forwarding. <rdar://problem/13249661>. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178285 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-28[ObjCARC] Strength reduce objc_retainBlock -> objc_retain if the ↵Michael Gottesman
objc_retainBlock is optimizable. If an objc_retainBlock has the copy_on_escape metadata attached to it AND if the block pointer argument only escapes down the stack, we are allowed to strength reduce the objc_retainBlock to to an objc_retain and thus optimize it. Current there is logic in the ARC data flow analysis to handle this case which is complicated and involved making distinctions in between objc_retainBlock and objc_retain in certain places and considering them the same in others. This patch simplifies said code by: 1. Performing the strength reduction in the initial ARC peephole analysis (ObjCARCOpts::OptimizeIndividualCalls). 2. Changes the ARC dataflow analysis (which runs after the peephole analysis) to consider all objc_retainBlock calls to not be optimizable (since if the call was optimizable, we would have strength reduced it already). This patch leaves in the infrastructure in the ARC dataflow analysis to handle this case, which due to 2 will just be dead code. I am doing this on purpose to separate the removal of the old code from the testing of the new code. <rdar://problem/13249661>. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178284 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-28[tsan] make sure memset/memcpy/memmove are not inlined in tsan modeKostya Serebryany
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178230 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-28Check if Type is a vector before calling function Type::getVectorNumElements.Akira Hatanaka
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178208 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-26Use the full path when outputting the `.gcda' file.Bill Wendling
If we compile a single source program, the `.gcda' file will be generated where the program was executed. This isn't desirable, because that place may be at an unpredictable place (the program could call `chdir' for instance). Instead, we will output the `.gcda' file in the same place we output the `.gcno' file. I.e., the directory where the executable was generated. This matches GCC's behavior. <rdar://problem/13061072> & PR11809 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178084 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-26Make InstCombineCasts.cpp:OptimizeIntToFloatBitCast endian safe.Ulrich Weigand
The OptimizeIntToFloatBitCast converts shift-truncate sequences into extractelement operations. The computation of the element index to be used in the resulting operation is currently only correct for little-endian targets. This commit fixes the element index computation to be correct for big-endian targets as well. If the target byte order is unknown, the optimization cannot be performed at all. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178031 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-26[ASan] Change the ABI of __asan_before_dynamic_init function: now it takes ↵Alexey Samsonov
pointer to private string with module name. This string serves as a unique module ID in ASan runtime. LLVM part git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178013 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-26[ObjCARC Annotations] Added support for displaying the state of pointers at ↵Michael Gottesman
the bottom/top of BBs of the ARC dataflow analysis for both bottomup and topdown analyses. This will allow for verification and analysis of the merge function of the data flow analyses in the ARC optimizer. The actual implementation of this feature is by introducing calls to the functions llvm.arc.annotation.{bottomup,topdown}.{bbstart,bbend} which are only declared. Each such call takes in a pointer to a global with the same name as the pointer whose provenance is being tracked and a pointer whose name is one of our Sequence states and points to a string that contains the same name. To ensure that the optimizer does not consider these annotations in any way, I made it so that the annotations are considered to be of IC_None type. A test case is included for this commit and the previous ObjCARCAnnotation commit. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177952 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-26[ObjCARC Annotations] Implemented ARC annotation metadata to expose the ARC ↵Michael Gottesman
data flow analysis state in the IR via metadata. Previously the inner works of the data flow analysis in ObjCARCOpts was hard to get out of the optimizer for analysis of bugs or testing. All of the current ARC unit tests are based off of testing the effect of the data flow analysis (i.e. what statements are removed or moved, etc.). This creates weakness in the current unit testing regimem since we are not actually testing what effects various instructions have on the modeled pointer state. Additionally in order to analyze a bug in the optimizer, one would need to track by hand what the optimizer was actually doing either through use of DEBUG statements or through the usage of a debugger, both yielding large loses in developer productivity. This patch deals with these two issues by providing ARC annotation metadata that annotates instructions with the state changes that they cause in various pointers as well as provides metadata to annotate provenance sources. Specifically, we introduce the following metadata types: 1. llvm.arc.annotation.bottomup. 2. llvm.arc.annotation.topdown. 3. llvm.arc.annotation.provenancesource. llvm.arc.annotation.{bottomup,topdown}: These annotations describes a state change in a pointer when we are visiting instructions bottomup/topdown respectively. The output format for both is the same: !1 = metadata !{metadata !"(test,%x)", metadata !"S_Release", metadata !"S_Use"} The first element is a string tuple with the following format: (function,variable name) The second two elements of the metadata show the previous state of the pointer (in this case S_Release) and the new state of the pointer (S_Use). We write the metadata in such a manner to ensure that it is easy for outside tools to parse. This is important since I am currently working on a tool for taking this information and pretty printing it besides the IR and that can be used for LIT style testing via the generation of an index. llvm.arc.annotation.provenancesource: This metadata is used to annotate instructions which act as provenance sources, i.e. ones that introduce a new (from the optimizer's perspective) non-argument pointer to track. This enables cross-referencing in between provenance sources and the state changes that occur to them. This is still a work in progress. Additionally I plan on committing later today additions to the annotations that annotate at the top/bottom of basic blocks the state of the various pointers being tracked. *NOTE* The metadata support is conditionally compiled into libObjCARCOpts only when we are producing a debug build of llvm/clang and even so are disabled by default. To enable the annotation metadata, pass in -enable-objc-arc-annotations to opt. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177951 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-25Fix a bug in fast-math fadd/fsub simplification. Shuxin Yang
The problem is that the code mistakenly took for granted that following constructor is able to create an APFloat from a *SIGNED* integer: APFloat::APFloat(const fltSemantics &ourSemantics, integerPart value) rdar://13486998 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177906 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-25Address issues found by Duncan during post-commit review of r177856.Arnaud A. de Grandmaison
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177863 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-25InstCombine: simplify comparisons to zero of (shl %x, Cst) or (mul %x, Cst)Arnaud A. de Grandmaison
This simplification happens at 2 places : - using the nsw attribute when the shl / mul is used by a sign test - when the shl / mul is compared for (in)equality to zero git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177856 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-25Changed isNullOrUndef => IsNullOrUndef and isNoopInstruction => ↵Michael Gottesman
IsNoopInstruction so that all helper functions are named similarly in ObjCARC.h. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177855 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-24Minor cleanups. No functionality change.Jakub Staszak
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177837 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-24Use dyn_cast instead of isa && cast.Jakub Staszak
No functionality change. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177836 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-23Change method name ClearRefCount => ClearKnownPositiveRefCount to match the ↵Michael Gottesman
name of the member that it is modifying. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177818 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-23Changed the method name PtrState.IsKnownIncremented() to ↵Michael Gottesman
PtrState.HasKnownPositiveRefCount(). Now said method matches namewise every other method which refers to the member KnownPositiveRefCount of the class PtrState. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177816 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-22Kill every call to @clang.arc.use in the ARC contract phase.John McCall
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177769 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-22Add all clauses when merging the landing pads. Duplicates will be handled ↵Bill Wendling
later on. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177757 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-22Don't use the removed API.Bill Wendling
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177749 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-22[asan] Change the way we report the alloca frame on stack-buff-overflow.Kostya Serebryany
Before: the function name was stored by the compiler as a constant string and the run-time was printing it. Now: the PC is stored instead and the run-time prints the full symbolized frame. This adds a couple of instructions into every function with non-empty stack frame, but also reduces the binary size because we store less strings (I saw 2% size reduction). This change bumps the asan ABI version to v3. llvm part. Example of report (now): ==31711==ERROR: AddressSanitizer: stack-buffer-overflow on address 0x7fffa77cf1c5 at pc 0x41feb0 bp 0x7fffa77cefb0 sp 0x7fffa77cefa8 READ of size 1 at 0x7fffa77cf1c5 thread T0 #0 0x41feaf in Frame0(int, char*, char*, char*) stack-oob-frames.cc:20 #1 0x41f7ff in Frame1(int, char*, char*) stack-oob-frames.cc:24 #2 0x41f477 in Frame2(int, char*) stack-oob-frames.cc:28 #3 0x41f194 in Frame3(int) stack-oob-frames.cc:32 #4 0x41eee0 in main stack-oob-frames.cc:38 #5 0x7f0c5566f76c (/lib/x86_64-linux-gnu/libc.so.6+0x2176c) #6 0x41eb1c (/usr/local/google/kcc/llvm_cmake/a.out+0x41eb1c) Address 0x7fffa77cf1c5 is located in stack of thread T0 at offset 293 in frame #0 0x41f87f in Frame0(int, char*, char*, char*) stack-oob-frames.cc:12 <<<<<<<<<<<<<< this is new This frame has 6 object(s): [32, 36) 'frame.addr' [96, 104) 'a.addr' [160, 168) 'b.addr' [224, 232) 'c.addr' [288, 292) 's' [352, 360) 'd' git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177724 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-22tsan: handle vptr loads speciallyDmitry Vyukov
This is required to determine ctor/dtor vs virtual call races. http://llvm-reviews.chandlerc.com/D566 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177717 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-22Fix llvm::removeUnreachableBlocks to handle unreachable loops.Evgeniy Stepanov
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177713 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-22InstCombine: Improve the result bitvect type when folding (cmp pred (load ↵Arnaud A. de Grandmaison
(gep GV, i)) C) to a bit test. The original code used i32, and i64 if legal. This introduced unneeded casts when they aren't legal, or when the index variable i has another type. In order of preference: try to use i's type; use the smallest fitting legal type (using an added DataLayout method); default to i32. A testcase checks that this works when the index gep operand is i16. Patch by : Ahmed Bougacha <ahmed.bougacha@gmail.com> Reviewed by : Duncan git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177712 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-21Always forward 'resume' instructions to the outter landing pad.Bill Wendling
How did this ever work? Basically, if you have a function that's inlined into the caller, it may not have any 'call' instructions, but any 'resume' instructions it may have should still be forwarded to the outer (caller's) landing pad. This requires that all of the 'landingpad' instructions in the callee have their clauses merged with the caller's outer 'landingpad' instruction (hence the bit of ugly code in the `forwardResume' method). Testcase in a follow commit to the test-suite repository. <rdar://problem/13360379> & PR15555 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177680 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-21[SROA] Prefix names using a custom IRBuilder inserter.Chandler Carruth
The key part of this is ensuring that name prefixes remain in a Twine form until we get to a point where we can nuke them under NDEBUG. This is tricky using the old APIs as they played fast and loose with Twine, which is prone to serious error. The inserter is much cleaner as it is actually in the call stack leading to the setName call, and so has a good opportunity to prepend the prefix. This matters more than you might imagine because most runs over an alloca find a single partition, and rewrite 3 or 4 instructions referring to it. As a consequence doing this lazily and exclusively with Twine allows the optimizer to delete more of it and shaves another 2% to 3% off of the release build's SROA run time for PR15412. I also think the APIs are cleaner, and the use of Twine is more reliable, so I consider it a win-win despite the churn required to reach this state. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177631 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-21[msan] Add an option to disable poisoning of shadow for undef values.Evgeniy Stepanov
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177630 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-21simplify-libcalls: Removed unused variableMeador Inge
The 'Modified' variable should have been removed from SimplifyLibCalls in r177619, but was missed. This commit removes it. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177622 91177308-0d34-0410-b5e6-96231b3b80d8