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* [MemCpyOpt] Look at any dependency -not just source- for memset+memcpy.Ahmed Bougacha2015-05-111-6/+7
| | | | | | | | | | This fixes another miscompile introduced by r235232: when there was a dependency on the memcpy destination other than the memset, we would ignore it, because we only looked at the source dependency. It was a mistake to use SrcDepInfo. Instead, just use DepInfo. llvm-svn: 237066
* [MemCpyOpt] Use the raw i8* dest when optimizing memset+memcpy.Ahmed Bougacha2015-04-211-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | MemIntrinsic::getDest() looks through pointer casts, and using it directly when building the new GEP+memset results in stuff like: %0 = getelementptr i64* %p, i32 16 %1 = bitcast i64* %0 to i8* call ..memset(i8* %1, ...) instead of the correct: %0 = bitcast i64* %p to i8* %1 = getelementptr i8* %0, i32 16 call ..memset(i8* %1, ...) Instead, use getRawDest, which just gives you the i8* value. While there, use the memcpy's dest, as it's live anyway. In most cases, when the optimization triggers, the memset and memcpy sizes are the same, so the built memset is 0-sized and eliminated. The problem occurs when they're different. Fixes a regression caused by r235232: PR23300. llvm-svn: 235419
* [MemCpyOpt] Don't force i64 when promoting memset/memcpy sizes.Ahmed Bougacha2015-04-181-3/+6
| | | | | | | | | | Harden r235258 to support any integer bitwidth. The quick glance at the reference made me think only i32 and i64 were valid types, but they're not special, so any overload is legal. Thanks to David Majnemer for noticing! llvm-svn: 235261
* [MemCpyOpt] Promote both memset/memcpy sizes if differently typed.Ahmed Bougacha2015-04-181-0/+6
| | | | | | | | | | | | | Followup to r235232, which caused PR23278. We can't assume the memset and memcpy sizes have the same type, as nothing in the language reference prevents that. Instead, zext both to i64 if they disagree. While there, robustify tests by using i8 %c rather than i8 0 for the memset character. llvm-svn: 235258
* [MemCpyOpt] Optimize double-storing by memset+memcpy.Ahmed Bougacha2015-04-171-3/+59
| | | | | | | | | | | | | | | | | | A common idiom in some code is to do the following: memset(dst, 0, dst_size); memcpy(dst, src, src_size); Some of the memset is redundant; instead, we can do: memcpy(dst, src, src_size); memset(dst + src_size, 0, dst_size <= src_size ? 0 : dst_size - src_size); Original patch by: Joel Jones Differential Revision: http://reviews.llvm.org/D498 llvm-svn: 235232
* [CallSite] Make construction from Value* (or Instruction*) explicit.Benjamin Kramer2015-04-101-1/+1
| | | | | | | | | | | | | | | | | | | CallSite roughly behaves as a common base CallInst and InvokeInst. Bring the behavior closer to that model by making upcasts explicit. Downcasts remain implicit and work as before. Following dyn_cast as a mental model checking whether a Value *V isa CallSite now looks like this: if (auto CS = CallSite(V)) // think dyn_cast instead of: if (CallSite CS = V) This is an extra token but I think it is slightly clearer. Making the ctor explicit has the advantage of not accidentally creating nullptr CallSites, e.g. when you pass a Value * to a function taking a CallSite argument. llvm-svn: 234601
* Re-sort includes with sort-includes.py and insert raw_ostream.h where it's used.Benjamin Kramer2015-03-231-1/+1
| | | | llvm-svn: 232998
* DataLayout is mandatory, update the API to reflect it with references.Mehdi Amini2015-03-101-45/+38
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: Now that the DataLayout is a mandatory part of the module, let's start cleaning the codebase. This patch is a first attempt at doing that. This patch is not exactly NFC as for instance some places were passing a nullptr instead of the DataLayout, possibly just because there was a default value on the DataLayout argument to many functions in the API. Even though it is not purely NFC, there is no change in the validation. I turned as many pointer to DataLayout to references, this helped figuring out all the places where a nullptr could come up. I had initially a local version of this patch broken into over 30 independant, commits but some later commit were cleaning the API and touching part of the code modified in the previous commits, so it seemed cleaner without the intermediate state. Test Plan: Reviewers: echristo Subscribers: llvm-commits From: Mehdi Amini <mehdi.amini@apple.com> llvm-svn: 231740
* Make DataLayout Non-Optional in the ModuleMehdi Amini2015-03-041-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: DataLayout keeps the string used for its creation. As a side effect it is no longer needed in the Module. This is "almost" NFC, the string is no longer canonicalized, you can't rely on two "equals" DataLayout having the same string returned by getStringRepresentation(). Get rid of DataLayoutPass: the DataLayout is in the Module The DataLayout is "per-module", let's enforce this by not duplicating it more than necessary. One more step toward non-optionality of the DataLayout in the module. Make DataLayout Non-Optional in the Module Module->getDataLayout() will never returns nullptr anymore. Reviewers: echristo Subscribers: resistor, llvm-commits, jholewinski Differential Revision: http://reviews.llvm.org/D7992 From: Mehdi Amini <mehdi.amini@apple.com> llvm-svn: 231270
* Properly update AA metadata when performing call slot optimizationBjorn Steinbrink2015-02-071-0/+10
| | | | | | | | Subscribers: llvm-commits Differential Revision: http://reviews.llvm.org/D7482 llvm-svn: 228500
* [PM] Separate the TargetLibraryInfo object from the immutable pass.Chandler Carruth2015-01-151-3/+3
| | | | | | | | | | | | | | The pass is really just a means of accessing a cached instance of the TargetLibraryInfo object, and this way we can re-use that object for the new pass manager as its result. Lots of delta, but nothing interesting happening here. This is the common pattern that is developing to allow analyses to live in both the old and new pass manager -- a wrapper pass in the old pass manager emulates the separation intrinsic to the new pass manager between the result and pass for analyses. llvm-svn: 226157
* [PM] Move TargetLibraryInfo into the Analysis library.Chandler Carruth2015-01-151-1/+1
| | | | | | | | | | | | | | | | While the term "Target" is in the name, it doesn't really have to do with the LLVM Target library -- this isn't an abstraction which LLVM targets generally need to implement or extend. It has much more to do with modeling the various runtime libraries on different OSes and with different runtime environments. The "target" in this sense is the more general sense of a target of cross compilation. This is in preparation for porting this analysis to the new pass manager. No functionality changed, and updates inbound for Clang and Polly. llvm-svn: 226078
* [PM] Split the AssumptionTracker immutable pass into two separate APIs:Chandler Carruth2015-01-041-6/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | a cache of assumptions for a single function, and an immutable pass that manages those caches. The motivation for this change is two fold. Immutable analyses are really hacks around the current pass manager design and don't exist in the new design. This is usually OK, but it requires that the core logic of an immutable pass be reasonably partitioned off from the pass logic. This change does precisely that. As a consequence it also paves the way for the *many* utility functions that deal in the assumptions to live in both pass manager worlds by creating an separate non-pass object with its own independent API that they all rely on. Now, the only bits of the system that deal with the actual pass mechanics are those that actually need to deal with the pass mechanics. Once this separation is made, several simplifications become pretty obvious in the assumption cache itself. Rather than using a set and callback value handles, it can just be a vector of weak value handles. The callers can easily skip the handles that are null, and eventually we can wrap all of this up behind a filter iterator. For now, this adds boiler plate to the various passes, but this kind of boiler plate will end up making it possible to port these passes to the new pass manager, and so it will end up factored away pretty reasonably. llvm-svn: 225131
* Allow call-slop optzn for destinations with a suitable dereferenceable attributeBjorn Steinbrink2014-10-161-14/+16
| | | | | | | | | | | | | | | Summary: Currently, call slot optimization requires that if the destination is an argument, the argument has the sret attribute. This is to ensure that the memory access won't trap. In addition to sret, we can also allow the optimization to happen for arguments that have the new dereferenceable attribute, which gives the same guarantee. Subscribers: llvm-commits Differential Revision: http://reviews.llvm.org/D5832 llvm-svn: 219950
* Make use of @llvm.assume in ValueTracking (computeKnownBits, etc.)Hal Finkel2014-09-071-1/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This change, which allows @llvm.assume to be used from within computeKnownBits (and other associated functions in ValueTracking), adds some (optional) parameters to computeKnownBits and friends. These functions now (optionally) take a "context" instruction pointer, an AssumptionTracker pointer, and also a DomTree pointer, and most of the changes are just to pass this new information when it is easily available from InstSimplify, InstCombine, etc. As explained below, the significant conceptual change is that known properties of a value might depend on the control-flow location of the use (because we care that the @llvm.assume dominates the use because assumptions have control-flow dependencies). This means that, when we ask if bits are known in a value, we might get different answers for different uses. The significant changes are all in ValueTracking. Two main changes: First, as with the rest of the code, new parameters need to be passed around. To make this easier, I grouped them into a structure, and I made internal static versions of the relevant functions that take this structure as a parameter. The new code does as you might expect, it looks for @llvm.assume calls that make use of the value we're trying to learn something about (often indirectly), attempts to pattern match that expression, and uses the result if successful. By making use of the AssumptionTracker, the process of finding @llvm.assume calls is not expensive. Part of the structure being passed around inside ValueTracking is a set of already-considered @llvm.assume calls. This is to prevent a query using, for example, the assume(a == b), to recurse on itself. The context and DT params are used to find applicable assumptions. An assumption needs to dominate the context instruction, or come after it deterministically. In this latter case we only handle the specific case where both the assumption and the context instruction are in the same block, and we need to exclude assumptions from being used to simplify their own ephemeral values (those which contribute only to the assumption) because otherwise the assumption would prove its feeding comparison trivial and would be removed. This commit adds the plumbing and the logic for a simple masked-bit propagation (just enough to write a regression test). Future commits add more patterns (and, correspondingly, more regression tests). llvm-svn: 217342
* Fix a really bad miscompile introduced in r216865 - the else-if logicChandler Carruth2014-09-011-10/+14
| | | | | | | | | | | | | | | | | | chain became completely broken here as *all* intrinsic users ended up being skipped, and the ones that seemed to be singled out were actually the exact wrong set. This is a great example of why long else-if chains can be easily confusing. Switch the entire code to use early exits and early continues to have simpler (and more importantly, correct) logic here, as well as fixing the reversed logic for detecting and continuing on lifetime intrinsics. I've also significantly cleaned up the test case and added another test case demonstrating an example where the optimization is not (trivially) safe to perform. llvm-svn: 216871
* Ignore lifetime intrinsics in use list for MemCpyOptimizer. Patch by Luqman ↵Nick Lewycky2014-09-011-0/+4
| | | | | | Aden, review by Hal Finkel. llvm-svn: 216865
* Don't eliminate memcpy's when the address of the pointer may itself be ↵Nick Lewycky2014-07-141-0/+6
| | | | | | relevant. Fixes PR18304. Patch by David Wiberg! llvm-svn: 212970
* [C++] Use 'nullptr'. Transforms edition.Craig Topper2014-04-251-19/+19
| | | | llvm-svn: 207196
* [Modules] Fix potential ODR violations by sinking the DEBUG_TYPEChandler Carruth2014-04-221-1/+2
| | | | | | | | | | | | | | | | | definition below all of the header #include lines, lib/Transforms/... edition. This one is tricky for two reasons. We again have a couple of passes that define something else before the includes as well. I've sunk their name macros with the DEBUG_TYPE. Also, InstCombine contains headers that need DEBUG_TYPE, so now those headers #define and #undef DEBUG_TYPE around their code, leaving them well formed modular headers. Fixing these headers was a large motivation for all of these changes, as "leaky" macros of this form are hard on the modules implementation. llvm-svn: 206844
* Treat lifetime.start'd memory like we treat freshly alloca'd memory. Patch ↵Nick Lewycky2014-03-261-4/+16
| | | | | | by Björn Steinbrink! llvm-svn: 204876
* MemCpyOpt: When merging memsets also merge the trivial case of two memsets ↵Benjamin Kramer2014-03-101-0/+7
| | | | | | | | with the same destination. The testcase is from PR19092, but I think the bug described there is actually a clang issue. llvm-svn: 203489
* [C++11] Add range based accessors for the Use-Def chain of a Value.Chandler Carruth2014-03-091-12/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This requires a number of steps. 1) Move value_use_iterator into the Value class as an implementation detail 2) Change it to actually be a *Use* iterator rather than a *User* iterator. 3) Add an adaptor which is a User iterator that always looks through the Use to the User. 4) Wrap these in Value::use_iterator and Value::user_iterator typedefs. 5) Add the range adaptors as Value::uses() and Value::users(). 6) Update *all* of the callers to correctly distinguish between whether they wanted a use_iterator (and to explicitly dig out the User when needed), or a user_iterator which makes the Use itself totally opaque. Because #6 requires churning essentially everything that walked the Use-Def chains, I went ahead and added all of the range adaptors and switched them to range-based loops where appropriate. Also because the renaming requires at least churning every line of code, it didn't make any sense to split these up into multiple commits -- all of which would touch all of the same lies of code. The result is still not quite optimal. The Value::use_iterator is a nice regular iterator, but Value::user_iterator is an iterator over User*s rather than over the User objects themselves. As a consequence, it fits a bit awkwardly into the range-based world and it has the weird extra-dereferencing 'operator->' that so many of our iterators have. I think this could be fixed by providing something which transforms a range of T&s into a range of T*s, but that *can* be separated into another patch, and it isn't yet 100% clear whether this is the right move. However, this change gets us most of the benefit and cleans up a substantial amount of code around Use and User. =] llvm-svn: 203364
* [C++11] Add 'override' keyword to virtual methods that override their base ↵Craig Topper2014-03-051-2/+2
| | | | | | class. llvm-svn: 202953
* [Modules] Move GetElementPtrTypeIterator into the IR library. As itsChandler Carruth2014-03-041-1/+1
| | | | | | | | | name might indicate, it is an iterator over the types in an instruction in the IR.... You see where this is going. Another step of modularizing the support library. llvm-svn: 202815
* Make DataLayout a plain object, not a pass.Rafael Espindola2014-02-251-1/+2
| | | | | | | Instead, have a DataLayoutPass that holds one. This will allow parts of LLVM don't don't handle passes to also use DataLayout. llvm-svn: 202168
* Rename many DataLayout variables from TD to DL.Rafael Espindola2014-02-211-24/+24
| | | | | | | | | I am really sorry for the noise, but the current state where some parts of the code use TD (from the old name: TargetData) and other parts use DL makes it hard to write a patch that changes where those variables come from and how they are passed along. llvm-svn: 201827
* A memcpy out of an fresh alloca is a no-op, delete it. Patch by Patrick Walton!Nick Lewycky2014-02-061-1/+11
| | | | llvm-svn: 200907
* Disable most IR-level transform passes on functions marked 'optnone'.Paul Robinson2014-02-061-0/+3
| | | | | | | | | Ideally only those transform passes that run at -O0 remain enabled, in reality we get as close as we reasonably can. Passes are responsible for disabling themselves, it's not the job of the pass manager to do it for them. llvm-svn: 200892
* Self-memcpy-elision and memcpy of constant byte to memset transforms don't ↵Nick Lewycky2014-02-041-4/+7
| | | | | | care how many bytes you were trying to transfer. Sink that safety test after those transforms. Noticed by inspection. llvm-svn: 200726
* Handle an addrspacecast case in memcpyoptMatt Arsenault2014-01-221-1/+1
| | | | llvm-svn: 199836
* [PM] Split DominatorTree into a concrete analysis result object whichChandler Carruth2014-01-131-3/+3
| | | | | | | | | | | | | | | | | | | | | | | can be used by both the new pass manager and the old. This removes it from any of the virtual mess of the pass interfaces and lets it derive cleanly from the DominatorTreeBase<> template. In turn, tons of boilerplate interface can be nuked and it turns into a very straightforward extension of the base DominatorTree interface. The old analysis pass is now a simple wrapper. The names and style of this split should match the split between CallGraph and CallGraphWrapperPass. All of the users of DominatorTree have been updated to match using many of the same tricks as with CallGraph. The goal is that the common type remains the resulting DominatorTree rather than the pass. This will make subsequent work toward the new pass manager significantly easier. Also in numerous places things became cleaner because I switched from re-running the pass (!!! mid way through some other passes run!!!) to directly recomputing the domtree. llvm-svn: 199104
* [cleanup] Move the Dominators.h and Verifier.h headers into the IRChandler Carruth2014-01-131-1/+1
| | | | | | | | | | | | | | | | | | directory. These passes are already defined in the IR library, and it doesn't make any sense to have the headers in Analysis. Long term, I think there is going to be a much better way to divide these matters. The dominators code should be fully separated into the abstract graph algorithm and have that put in Support where it becomes obvious that evn Clang's CFGBlock's can use it. Then the verifier can manually construct dominance information from the Support-driven interface while the Analysis library can provide a pass which both caches, reconstructs, and supports a nice update API. But those are very long term, and so I don't want to leave the really confusing structure until that day arrives. llvm-svn: 199082
* MemCpyOptimizer: Use max legal int size instead of pointer sizeMatt Arsenault2013-09-161-5/+8
| | | | | | | | | | | | If there are no legal integers, assume 1 byte. This makes more sense than using the pointer size as a guess for the maximum GPR width. It is conceivable to want to use some 64-bit pointers on a target where 64-bit integers aren't legal. llvm-svn: 190817
* Use SmallVectorImpl::iterator/const_iterator instead of SmallVector to avoid ↵Craig Topper2013-07-031-1/+1
| | | | | | specifying the vector size. llvm-svn: 185540
* Fix a potential bug in r183584.Shuxin Yang2013-06-081-4/+8
| | | | | | | | | | | | | r183584 tries to derive some info from the code *AFTER* a call and apply these derived info to the code *BEFORE* the call, which is not always safe as the call in question may never return, and in this case, the derived info is invalid. Thank Duncan for pointing out this potential bug. rdar://14073661 llvm-svn: 183606
* Fix an assertion in MemCpyOpt pass.Shuxin Yang2013-06-071-2/+4
| | | | | | | | | | | | | | | | | | | | | The MemCpyOpt pass is capable of optimizing: callee(&S); copy N bytes from S to D. into: callee(&D); subject to some legality constraints. Assertion is triggered when the compiler tries to evalute "sizeof(typeof(D))", while D is an opaque-typed, 'sret' formal argument of function being compiled. i.e. the signature of the func being compiled is something like this: T caller(...,%opaque* noalias nocapture sret %D, ...) The fix is that when come across such situation, instead of calling some utility functions to get the size of D's type (which will crash), we simply assume D has at least N bytes as implified by the copy-instruction. rdar://14073661 llvm-svn: 183584
* Move all of the header files which are involved in modelling the LLVM IRChandler Carruth2013-01-021-5/+5
| | | | | | | | | | | | | | | | | | | | | into their new header subdirectory: include/llvm/IR. This matches the directory structure of lib, and begins to correct a long standing point of file layout clutter in LLVM. There are still more header files to move here, but I wanted to handle them in separate commits to make tracking what files make sense at each layer easier. The only really questionable files here are the target intrinsic tablegen files. But that's a battle I'd rather not fight today. I've updated both CMake and Makefile build systems (I think, and my tests think, but I may have missed something). I've also re-sorted the includes throughout the project. I'll be committing updates to Clang, DragonEgg, and Polly momentarily. llvm-svn: 171366
* Use the new script to sort the includes of every file under lib.Chandler Carruth2012-12-031-5/+5
| | | | | | | | | | | | | | | | | Sooooo many of these had incorrect or strange main module includes. I have manually inspected all of these, and fixed the main module include to be the nearest plausible thing I could find. If you own or care about any of these source files, I encourage you to take some time and check that these edits were sensible. I can't have broken anything (I strictly added headers, and reordered them, never removed), but they may not be the headers you'd really like to identify as containing the API being implemented. Many forward declarations and missing includes were added to a header files to allow them to parse cleanly when included first. The main module rule does in fact have its merits. =] llvm-svn: 169131
* Revert the majority of the next patch in the address space series:Chandler Carruth2012-11-011-3/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | r165941: Resubmit the changes to llvm core to update the functions to support different pointer sizes on a per address space basis. Despite this commit log, this change primarily changed stuff outside of VMCore, and those changes do not carry any tests for correctness (or even plausibility), and we have consistently found questionable or flat out incorrect cases in these changes. Most of them are probably correct, but we need to devise a system that makes it more clear when we have handled the address space concerns correctly, and ideally each pass that gets updated would receive an accompanying test case that exercises that pass specificaly w.r.t. alternate address spaces. However, from this commit, I have retained the new C API entry points. Those were an orthogonal change that probably should have been split apart, but they seem entirely good. In several places the changes were very obvious cleanups with no actual multiple address space code added; these I have not reverted when I spotted them. In a few other places there were merge conflicts due to a cleaner solution being implemented later, often not using address spaces at all. In those cases, I've preserved the new code which isn't address space dependent. This is part of my ongoing effort to clean out the partial address space code which carries high risk and low test coverage, and not likely to be finished before the 3.2 release looms closer. Duncan and I would both like to see the above issues addressed before we return to these changes. llvm-svn: 167222
* Resubmit the changes to llvm core to update the functions to support ↵Micah Villmow2012-10-151-2/+3
| | | | | | different pointer sizes on a per address space basis. llvm-svn: 165941
* Revert 165732 for further review.Micah Villmow2012-10-111-3/+2
| | | | llvm-svn: 165747
* Add in the first iteration of support for llvm/clang/lldb to allow variable ↵Micah Villmow2012-10-111-2/+3
| | | | | | per address space pointer sizes to be optimized correctly. llvm-svn: 165726
* Move TargetData to DataLayout.Micah Villmow2012-10-081-9/+9
| | | | llvm-svn: 165402
* Move this test a bit later, after the point at which we know that we eitherDuncan Sands2012-10-051-10/+10
| | | | | | | | have an alloca or a parameter, since then the alloca test should make sense to readers, while before it probably appears too specific. No functionality change. llvm-svn: 165306
* In my recent change to avoid use of underaligned memory I didn't notice thatDuncan Sands2012-10-041-7/+7
| | | | | | | | cpyDest can be mutated in some cases, which would then cause a crash later if indeed the memory was underaligned. This brought down several buildbots, so I guess the underaligned case is much more common than I thought! llvm-svn: 165228
* The memcpy optimizer was happily doing call slot forwarding when the new memoryDuncan Sands2012-10-041-4/+30
| | | | | | | | | | was less aligned than the old. In the testcase this results in an overaligned memset: the memset alignment was correct for the original memory but is too much for the new memory. Fix this by either increasing the alignment of the new memory or bailing out if that isn't possible. Should fix the gcc-4.7 self-host buildbot failure. llvm-svn: 165220
* MemCpyOpt: When forming a memset from stores also take GEP constexprs into ↵Benjamin Kramer2012-09-131-3/+3
| | | | | | | | account. This is common when storing to global variables. llvm-svn: 163809
* Clean whitespaces.Nadav Rotem2012-07-241-82/+82
| | | | llvm-svn: 160668
* Move llvm/Support/IRBuilder.h -> llvm/IRBuilder.hChandler Carruth2012-06-291-4/+4
| | | | | | | | | | | | | | | | | This was always part of the VMCore library out of necessity -- it deals entirely in the IR. The .cpp file in fact was already part of the VMCore library. This is just a mechanical move. I've tried to go through and re-apply the coding standard's preferred header sort, but at 40-ish files, I may have gotten some wrong. Please let me know if so. I'll be committing the corresponding updates to Clang and Polly, and Duncan has DragonEgg. Thanks to Bill and Eric for giving the green light for this bit of cleanup. llvm-svn: 159421
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