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* Allow BB duplication threshold to be adjusted through JumpThreading's ctorMichael Liao2014-09-241-7/+10
| | | | | | | - BB duplication may not be desired on targets where there is no or small branch penalty and code duplication needs restrict control. llvm-svn: 218375
* Make use of @llvm.assume from LazyValueInfoHal Finkel2014-09-071-25/+46
| | | | | | | | | | | | | | | | | | | | | | | This change teaches LazyValueInfo to use the @llvm.assume intrinsic. Like with the known-bits change (r217342), this requires feeding a "context" instruction pointer through many functions. Aside from a little refactoring to reuse the logic that turns predicates into constant ranges in LVI, the only new code is that which can 'merge' the range from an assumption into that otherwise computed. There is also a small addition to JumpThreading so that it can have LVI use assumptions in the same block as the comparison feeding a conditional branch. With this patch, we can now simplify this as expected: int foo(int a) { __builtin_assume(a > 5); if (a > 3) { bar(); return 1; } return 0; } llvm-svn: 217345
* AA metadata refactoring (introduce AAMDNodes)Hal Finkel2014-07-241-9/+11
| | | | | | | | | | | | | | | | | | | | In order to enable the preservation of noalias function parameter information after inlining, and the representation of block-level __restrict__ pointer information (etc.), additional kinds of aliasing metadata will be introduced. This metadata needs to be carried around in AliasAnalysis::Location objects (and MMOs at the SDAG level), and so we need to generalize the current scheme (which is hard-coded to just one TBAA MDNode*). This commit introduces only the necessary refactoring to allow for the introduction of other aliasing metadata types, but does not actually introduce any (that will come in a follow-up commit). What it does introduce is a new AAMDNodes structure to hold all of the aliasing metadata nodes associated with a particular memory-accessing instruction, and uses that structure instead of the raw MDNode* in AliasAnalysis::Location, etc. No functionality change intended. llvm-svn: 213859
* Revert "[C++11] Add predecessors(BasicBlock *) / successors(BasicBlock *) ↵Duncan P. N. Exon Smith2014-07-211-8/+15
| | | | | | | | | iterator ranges." This reverts commit r213474 (and r213475), which causes a miscompile on a stage2 LTO build. I'll reply on the list in a moment. llvm-svn: 213562
* [C++11] Add predecessors(BasicBlock *) / successors(BasicBlock *) iterator ↵Manuel Jacob2014-07-201-15/+8
| | | | | | | | | | | | | | | | | | ranges. Summary: This patch introduces two new iterator ranges and updates existing code to use it. No functional change intended. Test Plan: All tests (make check-all) still pass. Reviewers: dblaikie Reviewed By: dblaikie Subscribers: llvm-commits Differential Revision: http://reviews.llvm.org/D4481 llvm-svn: 213474
* Fix an issue with the MergeBasicBlockIntoOnlyPred() helper function where it didOwen Anderson2014-07-121-5/+0
| | | | | | | | | | not properly handle the case where the predecessor block was the entry block to the function. The only in-tree client of this is JumpThreading, which worked around the issue in its own code. This patch moves the solution into the helper so that JumpThreading (and other clients) do not have to replicate the same fix everywhere. llvm-svn: 212875
* Updated comments as suggested by Rafael. Thanks.Dinesh Dwivedi2014-06-191-1/+7
| | | | llvm-svn: 211268
* Fixed jump threading going to infinite loop.Dinesh Dwivedi2014-06-171-0/+3
| | | | | | | | | This patch add code to remove unreachable blocks from function as they may cause jump threading to stuck in infinite loop. Differential Revision: http://reviews.llvm.org/D3991 llvm-svn: 211103
* [C++] Use 'nullptr'. Transforms edition.Craig Topper2014-04-251-18/+18
| | | | 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
* Consistent use of the noduplicate attribute.Eli Bendersky2014-03-171-1/+1
| | | | | | | | | The "noduplicate" attribute of call instructions is sometimes queried directly and sometimes through the cannotDuplicate() predicate. This patch streamlines all queries to use the cannotDuplicate() predicate. It also adds this predicate to InvokeInst, to mirror what CallInst has. llvm-svn: 204049
* [C++11] Add range based accessors for the Use-Def chain of a Value.Chandler Carruth2014-03-091-10/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 ValueHandle into the IR library where Value itself lives.Chandler Carruth2014-03-041-1/+1
| | | | | | | | | | | Move the test for this class into the IR unittests as well. This uncovers that ValueMap too is in the IR library. Ironically, the unittest for ValueMap is useless in the Support library (honestly, so was the ValueHandle test) and so it already lives in the IR unittests. Mmmm, tasty layering. llvm-svn: 202821
* 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
* Make some DataLayout pointers const.Rafael Espindola2014-02-241-1/+1
| | | | | | No functionality change. Just reduces the noise of an upcoming patch. llvm-svn: 202087
* Rename many DataLayout variables from TD to DL.Rafael Espindola2014-02-211-6/+6
| | | | | | | | | 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
* 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
* Don't eliminate a partially redundant load if it's in a landing pad.Bill Wendling2013-10-211-1/+6
| | | | | | | | | | | | A landing pad can be jumped to only by the unwind edge of an invoke instruction. If we eliminate a partially redundant load in a landing pad, it will create a basic block that violates this constraint. It then leads to other problems down the line if it tries to merge that basic block with the landing pad. Avoid this by not eliminating the load in a landing pad. PR17621 llvm-svn: 193064
* JumpThreading: Turn a select instruction into branching if it allows to ↵Benjamin Kramer2013-08-071-0/+83
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | thread one half of the select. This is a common pattern coming out of simplifycfg generating gross code. a: ; preds = %entry %sel = select i1 %cmp1, double %add, double 0.000000e+00 br label %b b: %cond5 = phi double [ %sel, %a ], [ %sub, %entry ] %cmp6 = fcmp oeq double %cond5, 0.000000e+00 br i1 %cmp6, label %if.then, label %if.end becomes a: br i1 %cmp1, label %b, label %if.then b: %cond5 = phi double [ %sub, %entry ], [ %add, %a ] %cmp6 = fcmp oeq double %cond5, 0.000000e+00 br i1 %cmp6, label %if.then, label %if.end Skipping block b completely if possible. llvm-svn: 187880
* Reimplement isPotentiallyReachable to make nocapture deduction much stronger.Nick Lewycky2013-07-271-2/+1
| | | | | | | | | | Adds unit tests for it too. Split BasicBlockUtils into an analysis-half and a transforms-half, and put the analysis bits into a new Analysis/CFG.{h,cpp}. Promote isPotentiallyReachable into llvm::isPotentiallyReachable and move it into Analysis/CFG. llvm-svn: 187283
* Move all of the header files which are involved in modelling the LLVM IRChandler Carruth2013-01-021-3/+3
| | | | | | | | | | | | | | | | | | | | | 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
* Add a new attribute, 'noduplicate'. If a function contains a noduplicate ↵James Molloy2012-12-201-1/+5
| | | | | | | | call, the call cannot be duplicated - Jump threading, loop unrolling, loop unswitching, and loop rotation are inhibited if they would duplicate the call. Similarly inlining of the function is inhibited, if that would duplicate the call (in particular inlining is still allowed when there is only one callsite and the function has internal linkage). llvm-svn: 170704
* Teach the jump threading optimization to stop scanning the basic block when ↵Nadav Rotem2012-12-031-5/+10
| | | | | | calculating the cost after passing the threshold. llvm-svn: 169135
* Use the new script to sort the includes of every file under lib.Chandler Carruth2012-12-031-13/+13
| | | | | | | | | | | | | | | | | 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
* Move TargetData to DataLayout.Micah Villmow2012-10-081-3/+3
| | | | llvm-svn: 165402
* Make MemoryBuiltins aware of TargetLibraryInfo.Benjamin Kramer2012-08-291-1/+1
| | | | | | | | | | | | | | | | This disables malloc-specific optimization when -fno-builtin (or -ffreestanding) is specified. This has been a problem for a long time but became more severe with the recent memory builtin improvements. Since the memory builtin functions are used everywhere, this required passing TLI in many places. This means that functions that now have an optional TLI argument, like RecursivelyDeleteTriviallyDeadFunctions, won't remove dead mallocs anymore if the TLI argument is missing. I've updated most passes to do the right thing. Fixes PR13694 and probably others. llvm-svn: 162841
* Clean whitespaces.Nadav Rotem2012-07-241-3/+3
| | | | llvm-svn: 160668
* Fix assertion in jump threading (PR13405).Richard Osborne2012-07-201-0/+2
| | | | | | | | GetBestDestForJumpOnUndef() assumes there is at least 1 successor, which isn't true if the block ends in an indirect branch with no successors. Fix this by bailing out earlier in this case. llvm-svn: 160546
* enhance jump threading to preserve TBAA information when PRE'ing loads,Chris Lattner2012-03-131-1/+12
| | | | | | | fixing rdar://11039258, an issue that came up when inspecting clang's bootstrapped codegen. llvm-svn: 152635
* Taken into account Duncan's comments for r149481 dated by 2nd Feb 2012:Stepan Dyatkovskiy2012-03-081-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20120130/136146.html Implemented CaseIterator and it solves almost all described issues: we don't need to mix operand/case/successor indexing anymore. Base iterator class is implemented as a template since it may be initialized either from "const SwitchInst*" or from "SwitchInst*". ConstCaseIt is just a read-only iterator. CaseIt is read-write iterator; it allows to change case successor and case value. Usage of iterator allows totally remove resolveXXXX methods. All indexing convertions done automatically inside the iterator's getters. Main way of iterator usage looks like this: SwitchInst *SI = ... // intialize it somehow for (SwitchInst::CaseIt i = SI->caseBegin(), e = SI->caseEnd(); i != e; ++i) { BasicBlock *BB = i.getCaseSuccessor(); ConstantInt *V = i.getCaseValue(); // Do something. } If you want to convert case number to TerminatorInst successor index, just use getSuccessorIndex iterator's method. If you want initialize iterator from TerminatorInst successor index, use CaseIt::fromSuccessorIndex(...) method. There are also related changes in llvm-clients: klee and clang. llvm-svn: 152297
* SwitchInst refactoring.Stepan Dyatkovskiy2012-02-011-3/+4
| | | | | | | | | | | | | | | | | The purpose of refactoring is to hide operand roles from SwitchInst user (programmer). If you want to play with operands directly, probably you will need lower level methods than SwitchInst ones (TerminatorInst or may be User). After this patch we can reorganize SwitchInst operands and successors as we want. What was done: 1. Changed semantics of index inside the getCaseValue method: getCaseValue(0) means "get first case", not a condition. Use getCondition() if you want to resolve the condition. I propose don't mix SwitchInst case indexing with low level indexing (TI successors indexing, User's operands indexing), since it may be dangerous. 2. By the same reason findCaseValue(ConstantInt*) returns actual number of case value. 0 means first case, not default. If there is no case with given value, ErrorIndex will returned. 3. Added getCaseSuccessor method. I propose to avoid usage of TerminatorInst::getSuccessor if you want to resolve case successor BB. Use getCaseSuccessor instead, since internal SwitchInst organization of operands/successors is hidden and may be changed in any moment. 4. Added resolveSuccessorIndex and resolveCaseIndex. The main purpose of these methods is to see how case successors are really mapped in TerminatorInst. 4.1 "resolveSuccessorIndex" was created if you need to level down from SwitchInst to TerminatorInst. It returns TerminatorInst's successor index for given case successor. 4.2 "resolveCaseIndex" converts low level successors index to case index that curresponds to the given successor. Note: There are also related compatability fix patches for dragonegg, klee, llvm-gcc-4.0, llvm-gcc-4.2, safecode, clang. llvm-svn: 149481
* SplitBlockPredecessors uses ArrayRef instead of Data and Size.Jakub Staszak2011-12-091-6/+3
| | | | llvm-svn: 146277
* Fix a few more places where TargetData/TargetLibraryInfo is not being passed.Chad Rosier2011-12-021-1/+6
| | | | | | Add FIXMEs to places that are non-trivial to fix. llvm-svn: 145661
* Change a bunch of isVolatile() checks to check for atomic load/store as well.Eli Friedman2011-09-121-2/+2
| | | | | | | | No tests; these changes aren't really interesting in the sense that the logic is the same for volatile and atomic. I believe this completes all of the changes necessary for the optimizer to handle loads and stores correctly. I'm going to try and come up with some additional testing, though. llvm-svn: 139533
* Calculate GetBestDestForJumpOnUndef correctly.Jakub Staszak2011-06-271-1/+3
| | | | llvm-svn: 133946
* Add a parameter to ConstantFoldTerminator() that callers can use to ask it ↵Frits van Bommel2011-05-221-1/+1
| | | | | | | | to also clean up the condition of any conditional terminator it folds to be unconditional, if that turns the condition into dead code. This just means it calls RecursivelyDeleteTriviallyDeadInstructions() in strategic spots. It defaults to the old behavior. I also changed -simplifycfg, -jump-threading and -codegenprepare to use this to produce slightly better code without any extra cleanup passes (AFAICT this was the only place in -simplifycfg where now-dead conditions of replaced terminators weren't being cleaned up). The only other user of this function is -sccp, but I didn't read that thoroughly enough to figure out whether it might be holding pointers to instructions that could be deleted by this. llvm-svn: 131855
* Preserve line number information while threading jumps.Devang Patel2011-05-041-2/+5
| | | | llvm-svn: 130880
* Fix an infinite alternation in JumpThreading where two transforms would ↵Owen Anderson2011-04-141-3/+15
| | | | | | | | | | repeatedly undo each other. The solution is to perform more aggressive constant folding to make one of the edges just folded away rather than trying to thread it. Fixes <rdar://problem/9284786>. Discovered with CSmith. llvm-svn: 129538
* Remove PHINode::reserveOperandSpace(). Instead, add a parameter toJay Foad2011-03-301-2/+2
| | | | | | PHINode::Create() giving the (known or expected) number of operands. llvm-svn: 128537
* (Almost) always call reserveOperandSpace() on newly created PHINodes.Jay Foad2011-03-301-2/+3
| | | | llvm-svn: 128535
* prevent jump threading from merging blocks when their address isChris Lattner2011-02-181-1/+11
| | | | | | | | | | | | | | | | | taken (and used!). This prevents merging the blocks (invalidating the block addresses) in a case like this: #define _THIS_IP_ ({ __label__ __here; __here: (unsigned long)&&__here; }) void foo() { printf("%p\n", _THIS_IP_); printf("%p\n", _THIS_IP_); printf("%p\n", _THIS_IP_); } which fixes PR4151. llvm-svn: 125829
* Fix a bug in the loop in JumpThreading::ProcessThreadableEdges() where it ↵Frits van Bommel2010-12-161-2/+2
| | | | | | | | could falsely produce a MultipleDestSentinel value if the first predecessor ended with an 'indirectbr'. If that happened, it caused an unnecessary FindMostPopularDest() call. This wasn't a correctness problem, but it broke the fast path for single-predecessor blocks. llvm-svn: 121966
* Teach jump threading to "look through" a select when the branch direction of ↵Frits van Bommel2010-12-151-0/+34
| | | | | | | | a terminator depends on it. When it sees a promising select it now tries to figure out whether the condition of the select is known in any of the predecessors and if so it maps the operands appropriately. llvm-svn: 121859
* simplify code and reduce indentationChris Lattner2010-12-131-32/+30
| | | | llvm-svn: 121670
* Remove some dead code from the jump threading pass.Frits van Bommel2010-12-071-141/+0
| | | | | | The last uses of these functions were removed in r113852 when LazyValueInfo was permanently enabled and removed the need for them. llvm-svn: 121133
* Implement jump threading of 'indirectbr' by keeping track of whether we're ↵Frits van Bommel2010-12-061-46/+80
| | | | | | looking for ConstantInt*s or BlockAddress*s. llvm-svn: 121066
* Refactor jump threading.Frits van Bommel2010-12-051-69/+73
| | | | | | | Should have no functional change other than the order of two transformations that are mutually-exclusive and the exact formatting of debug output. Internally, it now stores the ConstantInt*s as Constant*s, and actual undef values instead of nulls. llvm-svn: 120946
* Remove trailing whitespace.Frits van Bommel2010-12-051-208/+208
| | | | llvm-svn: 120945
* Get rid of static constructors for pass registration. Instead, every pass ↵Owen Anderson2010-10-191-1/+3
| | | | | | | | | | | | | | | | | exposes an initializeMyPassFunction(), which must be called in the pass's constructor. This function uses static dependency declarations to recursively initialize the pass's dependencies. Clients that only create passes through the createFooPass() APIs will require no changes. Clients that want to use the CommandLine options for passes will need to manually call the appropriate initialization functions in PassInitialization.h before parsing commandline arguments. I have tested this with all standard configurations of clang and llvm-gcc on Darwin. It is possible that there are problems with the static dependencies that will only be visible with non-standard options. If you encounter any crash in pass registration/creation, please send the testcase to me directly. llvm-svn: 116820
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