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* ValueMapper: Remove old FIXMEs; almost NFCDuncan P. N. Exon Smith2016-04-041-21/+1
| | | | | | | | | | | | | | | | | | | | | Remove a few old FIXMEs from the original commit of the Metadata/Value split in r223802. These are commented out assertions to the effect that calls between mapValue and mapMetadata never return nullptr. (The only behaviour change is that Mapper::mapSimpleMetadata memoizes the nullptr return.) When I originally rewrote the mapping code, I thought we could be stricter in the new metadata hierarchy and never return nullptr when RF_NullMapMissingGlobalValues was off. It's still not entirely clear to me why these assertions failed (a few months ago, I had a theory that I forgot to write down, but that's helping no one). Understood or not, I no longer see how these commented-out assertions would be useful. I'm relegating them to the annals of source control before making significant changes to ValueMapper.cpp. llvm-svn: 265282
* ValueMapper: Disallow metadata mapping recursion through mapValueDuncan P. N. Exon Smith2016-04-031-0/+5
| | | | | | | | | | | | | | | This adds an assertion to maintain the property from r265273. When Mapper::mapSimpleMetadata calls Mapper::mapValue, it should not find its way back to mapMetadataImpl. This guarantees that mapSimpleMetadata is not involved in any recursion. Since Mapper::mapValue calls out to arbitrary materializers, we need to save a bit on the ValueMap to make this assertion effective. There should be no functionality change here. This co-recursion should already have been impossible. llvm-svn: 265276
* Work around MSVC failure from r265273Duncan P. N. Exon Smith2016-04-031-0/+10
| | | | | | http://lab.llvm.org:8011/builders/sanitizer-windows/builds/19726 llvm-svn: 265275
* ValueMapper: Avoid recursion in mapSimplifiedMetadata, NFCDuncan P. N. Exon Smith2016-04-031-9/+64
| | | | | | | | | | | | | | | | | | | | | | | | | | The main change is to delay materializing GlobalValue initializers from Mapper::mapValue until Mapper::~Mapper. This effectively removes all recursion from mapSimplifiedMetadata, as promised in r265270. mapSimplifiedMetadata calls mapValue for ConstantAsMetadata nodes to find the mapped constant, and now it shouldn't be possible for mapValue to indirectly re-invoke mapMetadata. I'll add an assertion to that effect in a follow-up (separated so that the assertion can easily be reverted independently, if it comes to that). This a step toward a broader goal: converting Mapper::mapMetadataImpl from a recursive to an iterative algorithm. When a BlockAddress points at a BasicBlock inside an unmaterialized function body, we need to delay it until the function body is materialized in Mapper::~Mapper. This commit creates a temporary BasicBlock and returns a new BlockAddress, then RAUWs the BasicBlock once it is known. This situation should be extremely rare since a BlockAddress is usually used from within the function it's referencing (and BlockAddress itself is rare). There should be no observable functionality change. llvm-svn: 265273
* ValueMapper: Split out mapSimpleMetadata, NFCDuncan P. N. Exon Smith2016-04-031-4/+13
| | | | | | | | | | | | | | | | | | | | Split out a helper for mapping metadata without operands. This is any metadata that is not an MDNode, and any MDNode where the answer is known without looking at operands. Through some weird twists, this function is co-recursive: mapSimpleMetadata => MapValue => materializeInitFor => linkFunctionBody => RemapInstructions => MapMetadata => mapSimpleMetadata I plan to break the recursion in a follow-up. llvm-svn: 265270
* ValueMapper: Introduce Mapper helper class, NFCDuncan P. N. Exon Smith2016-04-031-85/+101
| | | | | | | Remove a bunch of boilerplate from ValueMapper.cpp by using a new file-local class called Mapper. llvm-svn: 265268
* [SimplifyLibCalls] Garbage collect dead code.Davide Italiano2016-04-031-28/+7
| | | | | | | | | | We already skip optimizations if the return value of printf() is used, so CI->use_empty() is always true. Differential Revision: http://reviews.llvm.org/D18656 llvm-svn: 265253
* Linker: Remove IRMover::isMetadataUnneeded indirection; almost NFCDuncan P. N. Exon Smith2016-04-021-3/+0
| | | | | | | | | | | | | | | | Instead of checking live during MapMetadata whether a subprogram is needed, seed the ValueMap with `nullptr` up-front. There is a small hypothetical functionality change. Previously, calling MapMetadataOp on a node whose "scope:" chain led to an unneeded subprogram would return nullptr. However, if that were ever called, then the subprogram would be needed; a situation that the IRMover is supposed to avoid a priori! Besides cleaning up the code a little, this restores a nice property: MapMetadataOp returns the same as MapMetadata. llvm-svn: 265229
* ValueMapper: Add support for seeding metadata with nullptrDuncan P. N. Exon Smith2016-04-021-4/+4
| | | | | | | | | | | | | Support seeding a ValueMap with nullptr for Metadata entries, a situation I didn't consider in the Metadata/Value split. I added a ValueMapper::getMappedMD accessor that returns an Optional<Metadata*> with the mapped (possibly null) metadata. IRMover needs to use this to avoid modifying the map when it's checking for unneeded subprograms. I updated a call from bugpoint since I find the new code clearer. llvm-svn: 265228
* Fix "warning: variabl 'XX’ set but not used" in release build (variable ↵Mehdi Amini2016-04-021-1/+1
| | | | | | | used in assertion, NFC) From: Mehdi Amini <mehdi.amini@apple.com> llvm-svn: 265220
* Don't insert stackrestore on deoptimizing returnsSanjoy Das2016-04-011-2/+4
| | | | | | | | They're not necessary (since the stack pointer is trivially restored on return), and the way LLVM inserts the stackrestore calls breaks the IR (we get a stackrestore between the deoptimize call and the return). llvm-svn: 265101
* Don't insert lifetime end markers on deoptimizing returnsSanjoy Das2016-04-011-2/+5
| | | | | | | | | They're not necessary (since the lifetime of the alloca is trivially over due to the return), and the way LLVM inserts the lifetime.end markers breaks the IR (we get a lifetime end marker between the deoptimize call and the return). llvm-svn: 265100
* Preserve blockaddress use edges in the module splitter.Evgeniy Stepanov2016-03-311-45/+46
| | | | | | | | "blockaddress" can not apply to an external function. All blockaddress constant uses must belong to the same module as the definition of the target function. llvm-svn: 265061
* Preserve extern_weak linkage in CloneModule.Evgeniy Stepanov2016-03-311-10/+15
| | | | | | | Only force "extern" linkage if the function used to be a definition in the source module. Declarations keep their original linkage. llvm-svn: 265043
* Introduce a @llvm.experimental.guard intrinsicSanjoy Das2016-03-311-5/+7
| | | | | | | | | | | | | | | | | | | | | | | Summary: As discussed on llvm-dev[1]. This change adds the basic boilerplate code around having this intrinsic in LLVM: - Changes in Intrinsics.td, and the IR Verifier - A lowering pass to lower @llvm.experimental.guard to normal control flow - Inliner support [1]: http://lists.llvm.org/pipermail/llvm-dev/2016-February/095523.html Reviewers: reames, atrick, chandlerc, rnk, JosephTremoulet, echristo Subscribers: mcrosier, llvm-commits Differential Revision: http://reviews.llvm.org/D18527 llvm-svn: 264976
* Cloning: Reduce complexity of debug info cloning and fix correctness issue.Peter Collingbourne2016-03-302-3/+11
| | | | | | | | | | | | | Commit r260791 contained an error in that it would introduce a cross-module reference in the old module. It also introduced O(N^2) complexity in the module cloner by requiring the entire module to be visited for each function. Fix both of these problems by avoiding use of the CloneDebugInfoMetadata function (which is only designed to do intra-module cloning) and cloning function-attached metadata in the same way that we clone all other metadata. Differential Revision: http://reviews.llvm.org/D18583 llvm-svn: 264935
* Remove HasFnAttribute guards to getFnAttribute callsNirav Dave2016-03-301-4/+2
| | | | | | | | | | | | These checks are redundant and can be removed Reviewers: hans Subscribers: llvm-commits, mzolotukhin Differential Revision: http://reviews.llvm.org/D18564 llvm-svn: 264872
* [MemorySSA] Make the visitor more careful with calls.George Burgess IV2016-03-301-5/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Prior to this patch, the MemorySSA caching visitor would cache all calls that it visited. When paired with phi optimization, this can be problematic. Consider: define void @foo() { ; 1 = MemoryDef(liveOnEntry) call void @clobberFunction() br i1 undef, label %if.end, label %if.then if.then: ; MemoryUse(??) call void @readOnlyFunction() ; 2 = MemoryDef(1) call void @clobberFunction() br label %if.end if.end: ; 3 = MemoryPhi(...) ; MemoryUse(?) call void @readOnlyFunction() ret void } When optimizing MemoryUse(?), we visit defs 1 and 2, so we note to cache them later. We ultimately end up not being able to optimize passed the Phi, so we set MemoryUse(?) to point to the Phi. We then cache the clobbering call for def 1 to be the Phi. This commit changes this behavior so that we wipe out any calls added to VisistedCalls while visiting the defs of a phi we couldn't optimize. Aside: With this patch, we now can bootstrap clang/LLVM without a single MemorySSA verifier failure. Woohoo. :) llvm-svn: 264820
* [MemorySSA] Change how the walker views/walks visited phis.George Burgess IV2016-03-301-22/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch teaches the caching MemorySSA walker a few things: 1. Not to walk Phis we've walked before. It seems that we tried to do this before, but it didn't work so well in cases like: define void @foo() { %1 = alloca i8 %2 = alloca i8 br label %begin begin: ; 3 = MemoryPhi({%0,liveOnEntry},{%end,2}) ; 1 = MemoryDef(3) store i8 0, i8* %2 br label %end end: ; MemoryUse(?) load i8, i8* %1 ; 2 = MemoryDef(1) store i8 0, i8* %2 br label %begin } Because we wouldn't put Phis in Q.Visited until we tried to visit them. So, when trying to optimize MemoryUse(?): - We would visit 3 above - ...Which would make us put {%0,liveOnEntry} in Q.Visited - ...Which would make us visit {%0,liveOnEntry} - ...Which would make us put {%end,2} in Q.Visited - ...Which would make us visit {%end,2} - ...Which would make us visit 3 - ...Which would realize we've already visited everything in 3 - ...Which would make us conservatively return 3. In the added test-case, (@looped_visitedonlyonce) this behavior would cause us to give incorrect results. Specifically, we'd visit 4 twice in the same query, but on the second visit, we'd skip while.cond because it had been visited, visit if.then/if.then2, and cache "1" as the clobbering def on the way back. 2. If we try to walk the defs of a {Phi,MemLoc} and see it has been visited before, just hand back the Phi we're trying to optimize. I promise this isn't as terrible as it seems. :) We now insert {Phi,MemLoc} pairs just before walking the Phi's upward defs. So, we check the cache for the {Phi,MemLoc} pair before checking if we've already walked the Phi. The {Phi,MemLoc} pair is (almost?) always guaranteed to have a cache entry if we've already fully walked it, because we cache as we go. So, if the {Phi,MemLoc} pair isn't in cache, either: (a) we must be in the process of visiting it (in which case, we can't give a better answer in a cache-as-we-go DFS walker) (b) we visited it, but didn't cache it on the way back (...which seems to require `ModifyingAccess` to not dominate `StartingAccess`, so I'm 99% sure that would be an error. If it's not an error, I haven't been able to get it to happen locally, so I suspect it's rare.) - - - - - As a consequence of this change, we no longer skip upward defs of phis, so we can kill the `VisitedOnlyOne` check. This gives us better accuracy than we had before, at the cost of potentially doing a bit more work when we have a loop. llvm-svn: 264814
* [ThinLTO] Remove post-pass metadata linking supportTeresa Johnson2016-03-291-64/+21
| | | | | | | | | | | Since we have moved to a model where functions are imported in bulk from each source module after making summary-based importing decisions, there is no longer a need to link metadata as a postpass, and all users have been removed. This essentially reverts r255909 and follow-on fixes. llvm-svn: 264763
* [SimlifyCFG] Prevent passes from destroying canonical loop structure, ↵Hyojin Sung2016-03-291-5/+19
| | | | | | | | | | | | | | | | | especially for nested loops When eliminating or merging almost empty basic blocks, the existence of non-trivial PHI nodes is currently used to recognize potential loops of which the block is the header and keep the block. However, the current algorithm fails if the loops' exit condition is evaluated only with volatile values hence no PHI nodes in the header. Especially when such a loop is an outer loop of a nested loop, the loop is collapsed into a single loop which prevent later optimizations from being applied (e.g., transforming nested loops into simplified forms and loop vectorization). The patch augments the existing PHI node-based check by adding a pre-test if the BB actually belongs to a set of loop headers and not eliminating it if yes. llvm-svn: 264697
* Remove personality for declarations in CloneModule.Evgeniy Stepanov2016-03-281-0/+2
| | | | | | | | | | Personality is copied as part of copyFunctionAttributes, but it is invalid on a declaration. Remove the personality attribute it the function body is not cloned. Also add a verifier run over output modules in the llvm-split tool. llvm-svn: 264667
* Revert "[SimlifyCFG] Prevent passes from destroying canonical loop ↵Reid Kleckner2016-03-281-20/+5
| | | | | | | | | | structure, especially for nested loops" This reverts commit r264596. It does not compile. llvm-svn: 264604
* [SimlifyCFG] Prevent passes from destroying canonical loop structure, ↵Hyojin Sung2016-03-281-5/+20
| | | | | | | | | | | | | | | | especially for nested loops When eliminating or merging almost empty basic blocks, the existence of non-trivial PHI nodes is currently used to recognize potential loops of which the block is the header and keep the block. However, the current algorithm fails if the loops' exit condition is evaluated only with volatile values hence no PHI nodes in the header. Especially when such a loop is an outer loop of a nested loop, the loop is collapsed into a single loop which prevent later optimizations from being applied (e.g., transforming nested loops into simplified forms and loop vectorization). The patch augments the existing PHI node-based check by adding a pre-test if the BB actually belongs to a set of loop headers and not eliminating it if yes. llvm-svn: 264596
* [SimplifyLibCalls] Transform printf("%s", "a") -> putchar('a').Davide Italiano2016-03-281-0/+18
| | | | llvm-svn: 264588
* [SimplifyCFG] propagate branch metadata when creating select (PR26636)Sanjay Patel2016-03-261-2/+2
| | | | llvm-svn: 264527
* [RS4GC] Lower calls to @llvm.experimental.deoptimizeSanjoy Das2016-03-251-9/+9
| | | | | | | | | | | | | | This changes RS4GC to lower calls to ``@llvm.experimental.deoptimize`` to gc.statepoints wrapping ``__llvm_deoptimize``, and changes ``callsGCLeafFunction`` to recognize ``@llvm.experimental.deoptimize`` as a non GC leaf function. I've had to hard code the ``"__llvm_deoptimize"`` name in RewriteStatepointsForGC; since ``TargetLibraryInfo`` is available only during codegen. This isn't without precedent in the codebase, so I'm not overtly concerned. llvm-svn: 264456
* Enable non-power-of-2 #pragma unroll counts.David L Kreitzer2016-03-251-21/+31
| | | | | | | | Patch by Evgeny Stupachenko. Differential Revision: http://reviews.llvm.org/D18202 llvm-svn: 264407
* Fix bugs in the MemorySSA walker.George Burgess IV2016-03-231-17/+35
| | | | | | | | | | | | | | | | | | There are a few bugs in the walker that this patch addresses. Primarily: - Caching can break when we have multiple BBs without phis - We weren't optimizing some phis properly - Because of how the DFS iterator works, there were times where we wouldn't cache any results of our DFS I left the test cases with FIXMEs in, because I'm not sure how much effort it will take to get those to work (read: We'll probably ultimately have to end up redoing the walker, or we'll have to come up with some creative caching tricks), and more test coverage = better. Differential Revision: http://reviews.llvm.org/D18065 llvm-svn: 264180
* [ModuleUtils] Use range-based loop. NFC.Davide Italiano2016-03-231-2/+1
| | | | llvm-svn: 264122
* [LoopVersioning] Relax an assert for LCSSA PHIsAdam Nemet2016-03-221-3/+4
| | | | | | | | | | | | | When you have multiple LCSSA (single-operand) PHIs that are converted into two-operand PHIs due to versioning, only assert that the PHI currently being converted has a single operand. I.e. we don't want to check PHIs that were converted earlier in the loop. Fixes PR27023. Thanks to Karl-Johan Karlsson for the minimized testcase! llvm-svn: 264081
* [MemorySSA] Consider def-only BBs for live-in calculations.George Burgess IV2016-03-211-6/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | If we have a BB with only MemoryDefs, live-in calculations will ignore it. This means we get results like this: define void @foo(i8* %p) { ; 1 = MemoryDef(liveOnEntry) store i8 0, i8* %p br i1 undef, label %if.then, label %if.end if.then: ; 2 = MemoryDef(1) store i8 1, i8* %p br label %if.end if.end: ; 3 = MemoryDef(1) store i8 2, i8* %p ret void } ...When there should be a MemoryPhi in the `if.end` BB. This patch fixes that behavior. llvm-svn: 263991
* [SimplifyLibCalls] Only consider sinpi/cospi functions within the same functionDavid Majnemer2016-03-191-7/+11
| | | | | | | | | | The sinpi/cospi can be replaced with sincospi to remove unnecessary computations. However, we need to make sure that the calls are within the same function! This fixes PR26993. llvm-svn: 263875
* Rework linkInModule(), making it oblivious to ThinLTOMehdi Amini2016-03-191-23/+13
| | | | | | | | | | | | | | | | | | | | | | | | Summary: ThinLTO is relying on linkInModule to import selected function. However a lot of "magic" was hidden in linkInModule and the IRMover, who would rename and promote global variables on the fly. This is moving to an approach where the steps are decoupled and the client is reponsible to specify the list of globals to import. As a consequence some test are changed because they were relying on the previous behavior which was importing the definition of *every* single global without control on the client side. Now the burden is on the client to decide if a global has to be imported or not. Reviewers: tejohnson Subscribers: joker.eph, llvm-commits Differential Revision: http://reviews.llvm.org/D18122 From: Mehdi Amini <mehdi.amini@apple.com> llvm-svn: 263863
* [IndVars] Make the fix for PR26973 more obvious; NFCISanjoy Das2016-03-181-3/+42
| | | | llvm-svn: 263828
* [IndVars] Pass the right loop to isLoopInvariantPredicateSanjoy Das2016-03-181-3/+2
| | | | | | | | | | | The loop on IVOperand's incoming values assumes IVOperand to be an induction variable on the loop over which `S Pred X` is invariant; otherwise loop invariant incoming values to IVOperand are not guaranteed to dominate the comparision. This fixes PR26973. llvm-svn: 263827
* [LoopVectorize] Annotate versioned loop with noalias metadataAdam Nemet2016-03-171-9/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: Use the new LoopVersioning facility (D16712) to add noalias metadata in the vector loop if we versioned with memchecks. This can enable some optimization opportunities further down the pipeline (see the included test or the benchmark improvement quoted in D16712). The test also covers the bug I had in the initial version in D16712. The vectorizer did not previously use LoopVersioning. The reason is that the vectorizer performs its transformations in single shot. It creates an empty single-block vector loop that it then populates with the widened, if-converted instructions. Thus creating an intermediate versioned scalar loop seems wasteful. So this patch (rather than bringing in LoopVersioning fully) adds a special interface to LoopVersioning to allow the vectorizer to add no-alias annotation while still performing its own versioning. As the vectorizer propagates metadata from the instructions in the original loop to the vector instructions we also check the pointer in the original instruction and see if LoopVersioning can add no-alias metadata based on the issued memchecks. Reviewers: hfinkel, nadav, mzolotukhin Subscribers: mzolotukhin, llvm-commits Differential Revision: http://reviews.llvm.org/D17191 llvm-svn: 263744
* [LoopVersioning] Annotate versioned loop with noalias metadataAdam Nemet2016-03-171-0/+89
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: If we decide to version a loop to benefit a transformation, it makes sense to record the now non-aliasing accesses in the newly versioned loop. This allows non-aliasing information to be used by subsequent passes. One example is 456.hmmer in SPECint2006 where after loop distribution, we vectorize one of the newly distributed loops. To vectorize we version this loop to fully disambiguate may-aliasing accesses. If we add the noalias markers, we can use the same information in a later DSE pass to eliminate some dead stores which amounts to ~25% of the instructions of this hot memory-pipeline-bound loop. The overall performance improves by 18% on our ARM64. The scoped noalias annotation is added in LoopVersioning. The patch then enables this for loop distribution. A follow-on patch will enable it for the vectorizer. Eventually this should be run by default when versioning the loop but first I'd like to get some feedback whether my understanding and application of scoped noalias metadata is correct. Essentially my approach was to have a separate alias domain for each versioning of the loop. For example, if we first version in loop distribution and then in vectorization of the distributed loops, we have a different set of memchecks for each versioning. By keeping the scopes in different domains they can conveniently be defined independently since different alias domains don't affect each other. As written, I also have a separate domain for each loop. This is not necessary and we could save some metadata here by using the same domain across the different loops. I don't think it's a big deal either way. Probably the best is to review the tests first to see if I mapped this problem correctly to scoped noalias markers. I have plenty of comments in the tests. Note that the interface is prepared for the vectorizer which needs the annotateInstWithNoAlias API. The vectorizer does not use LoopVersioning so we need a way to pass in the versioned instructions. This is also why the maps have to become part of the object state. Also currently, we only have an AA-aware DSE after the vectorizer if we also run the LTO pipeline. Depending how widely this triggers we may want to schedule a DSE toward the end of the regular pass pipeline. Reviewers: hfinkel, nadav, ashutosh.nema Subscribers: mssimpso, aemerson, llvm-commits, mcrosier Differential Revision: http://reviews.llvm.org/D16712 llvm-svn: 263743
* propagate 'unpredictable' metadata on select instructions Sanjay Patel2016-03-171-4/+3
| | | | | | | | | | | | This is similar to D18133 where we allowed profile weights on select instructions. This extends that change to also allow the 'unpredictable' attribute of branches to apply to selects. A test to check that 'unpredictable' metadata is preserved when cloning instructions was checked in at: http://reviews.llvm.org/rL263648 Differential Revision: http://reviews.llvm.org/D18220 llvm-svn: 263716
* [LV] Preserve LoopInfo when store predication is usedAdam Nemet2016-03-151-5/+10
| | | | | | | | | | | | | | | | | This was a latent bug that got exposed by the change to add LoopSimplify as a dependence to LoopLoadElimination. Since LoopInfo was corrupted after LV, LoopSimplify mis-compiled nbench in the test-suite (more details in the PR). The problem was that when we create the blocks for predicated stores we didn't add those to any loops. The original testcase for store predication provides coverage for this assuming we verify LI on the way out of LV. Fixes PR26952. llvm-svn: 263565
* Use some braces to format this a little better.Eric Christopher2016-03-151-5/+9
| | | | llvm-svn: 263527
* Fix llvm/llvm/lib/Transforms/Utils/LoopUnroll.cpp:285:53: error: suggestEric Christopher2016-03-151-11/+9
| | | | | | parentheses around '&&' within '||' [-Werror=parentheses]. llvm-svn: 263525
* [ThinLTO] Renaming of function index to module summary index (NFC)Teresa Johnson2016-03-151-4/+4
| | | | | | | | | | | | | | | (Resubmitting after fixing missing file issue) With the changes in r263275, there are now more than just functions in the summary. Completed the renaming of data structures (started in r263275) to reflect the wider scope. In particular, changed the FunctionIndex* data structures to ModuleIndex*, and renamed related variables and comments. Also renamed the files to reflect the changes. A companion clang patch will immediately succeed this patch to reflect this renaming. llvm-svn: 263513
* [LoopUnroll] Respect the convergent attribute.Justin Lebar2016-03-141-1/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: Specifically, when we perform runtime loop unrolling of a loop that contains a convergent op, we can only unroll k times, where k divides the loop trip multiple. Without this change, we'll happily unroll e.g. the following loop for (int i = 0; i < N; ++i) { if (i == 0) convergent_op(); foo(); } into int i = 0; if (N % 2 == 1) { convergent_op(); foo(); ++i; } for (; i < N - 1; i += 2) { if (i == 0) convergent_op(); foo(); foo(); }. This is unsafe, because we've just added a control-flow dependency to the convergent op in the prelude. In general, runtime unrolling loops that contain convergent ops is safe only if we don't have emit a prelude, which occurs when the unroll count divides the trip multiple. Reviewers: resistor Subscribers: llvm-commits, mzolotukhin Differential Revision: http://reviews.llvm.org/D17526 llvm-svn: 263509
* Revert "[ThinLTO] Renaming of function index to module summary index (NFC)"Teresa Johnson2016-03-141-4/+4
| | | | | | This reverts commit r263490. Missed a file. llvm-svn: 263493
* [ThinLTO] Renaming of function index to module summary index (NFC)Teresa Johnson2016-03-141-4/+4
| | | | | | | | | | | | | With the changes in r263275, there are now more than just functions in the summary. Completed the renaming of data structures (started in r263275) to reflect the wider scope. In particular, changed the FunctionIndex* data structures to ModuleIndex*, and renamed related variables and comments. Also renamed the files to reflect the changes. A companion clang patch will immediately succeed this patch to reflect this renaming. llvm-svn: 263490
* allow branch weight metadata on select instructions (PR26636)Sanjay Patel2016-03-141-1/+2
| | | | | | | | | | | | | | | | | | | | | | | As noted in: https://llvm.org/bugs/show_bug.cgi?id=26636 This doesn't accomplish anything on its own. It's the first step towards preserving and using branch weights with selects. The next step would be to make sure we're propagating the info in all of the other places where we create selects (SimplifyCFG, InstCombine, etc). I don't think there's an easy fix to make this happen; we have to look at each transform individually to determine how to correctly propagate the weights. Along with that step, we need to then use the weights when making subsequent transform decisions such as discussed in http://reviews.llvm.org/D16836. The inliner test is independent but closely related. It verifies that metadata is preserved when both branches and selects are cloned. Differential Revision: http://reviews.llvm.org/D18133 llvm-svn: 263482
* Remove PreserveNames template parameter from IRBuilderMehdi Amini2016-03-131-5/+5
| | | | | | | | This reapplies r263258, which was reverted in r263321 because of issues on Clang side. From: Mehdi Amini <mehdi.amini@apple.com> llvm-svn: 263393
* remove unnecessary cast; NFCSanjay Patel2016-03-121-4/+3
| | | | llvm-svn: 263343
* fix formatting; NFCSanjay Patel2016-03-121-12/+12
| | | | llvm-svn: 263342
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