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* Reverting r155468. Chris and Chandler have convinced me that it's dangerous andLang Hames2012-04-251-35/+0
| | | | | | | | in poor taste. Talking through some alternate solutions with Chandler. llvm-svn: 155530
* Add support for llvm.arm.neon.vmull* intrinsics to InstCombine. This fixesLang Hames2012-04-241-0/+35
| | | | | | <rdar://problem/11291436>. llvm-svn: 155468
* Reapply r155136 after fixing PR12599.Jakob Stoklund Olesen2012-04-231-39/+35
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Original commit message: Defer some shl transforms to DAGCombine. The shl instruction is used to represent multiplication by a constant power of two as well as bitwise left shifts. Some InstCombine transformations would turn an shl instruction into a bit mask operation, making it difficult for later analysis passes to recognize the constsnt multiplication. Disable those shl transformations, deferring them to DAGCombine time. An 'shl X, C' instruction is now treated mostly the same was as 'mul X, C'. These transformations are deferred: (X >>? C) << C --> X & (-1 << C) (When X >> C has multiple uses) (X >>? C1) << C2 --> X << (C2-C1) & (-1 << C2) (When C2 > C1) (X >>? C1) << C2 --> X >>? (C1-C2) & (-1 << C2) (When C1 > C2) The corresponding exact transformations are preserved, just like div-exact + mul: (X >>?,exact C) << C --> X (X >>?,exact C1) << C2 --> X << (C2-C1) (X >>?,exact C1) << C2 --> X >>?,exact (C1-C2) The disabled transformations could also prevent the instruction selector from recognizing rotate patterns in hash functions and cryptographic primitives. I have a test case for that, but it is too fragile. llvm-svn: 155362
* Revert r155136 "Defer some shl transforms to DAGCombine."Jakob Stoklund Olesen2012-04-201-35/+39
| | | | | | | | | While the patch was perfect and defect free, it exposed a really nasty bug in X86 SelectionDAG that caused an llc crash when compiling lencod. I'll put the patch back in after fixing the SelectionDAG problem. llvm-svn: 155181
* Defer some shl transforms to DAGCombine.Jakob Stoklund Olesen2012-04-191-39/+35
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The shl instruction is used to represent multiplication by a constant power of two as well as bitwise left shifts. Some InstCombine transformations would turn an shl instruction into a bit mask operation, making it difficult for later analysis passes to recognize the constsnt multiplication. Disable those shl transformations, deferring them to DAGCombine time. An 'shl X, C' instruction is now treated mostly the same was as 'mul X, C'. These transformations are deferred: (X >>? C) << C --> X & (-1 << C) (When X >> C has multiple uses) (X >>? C1) << C2 --> X << (C2-C1) & (-1 << C2) (When C2 > C1) (X >>? C1) << C2 --> X >>? (C1-C2) & (-1 << C2) (When C1 > C2) The corresponding exact transformations are preserved, just like div-exact + mul: (X >>?,exact C) << C --> X (X >>?,exact C1) << C2 --> X << (C2-C1) (X >>?,exact C1) << C2 --> X >>?,exact (C1-C2) The disabled transformations could also prevent the instruction selector from recognizing rotate patterns in hash functions and cryptographic primitives. I have a test case for that, but it is too fragile. llvm-svn: 155136
* Teach InstCombine to nuke a common alloca pattern -- an alloca which hasChandler Carruth2012-04-081-1/+70
| | | | | | | | | | | | GEPs, bit casts, and stores reaching it but no other instructions. These often show up during the iterative processing of the inliner, SROA, and DCE. Once we hit this point, we can completely remove the alloca. These were actually showing up in the final, fully optimized code in a bunch of inliner tests I've been working on, and notably they show up after LLVM finishes optimizing away all function calls involved in hash_combine(a, b). llvm-svn: 154285
* Always compute all the bits in ComputeMaskedBits.Rafael Espindola2012-04-046-42/+26
| | | | | | | | This allows us to keep passing reduced masks to SimplifyDemandedBits, but know about all the bits if SimplifyDemandedBits fails. This allows instcombine to simplify cases like the one in the included testcase. llvm-svn: 154011
* 153465 was incorrect. In this code we wanted to check that the pointer ↵Nadav Rotem2012-03-261-4/+3
| | | | | | operand is of pointer type (and not vector type). llvm-svn: 153468
* PR12357: The pointer was used before it was checked.Nadav Rotem2012-03-261-1/+3
| | | | llvm-svn: 153465
* eliminate an unneeded branch, part of PR12357Chris Lattner2012-03-261-7/+2
| | | | llvm-svn: 153458
* Revert r152907.Bill Wendling2012-03-161-15/+3
| | | | llvm-svn: 152935
* The alignment of the pointer part of the store instruction may have anBill Wendling2012-03-161-3/+15
| | | | | | | | | | alignment. If that's the case, then we want to make sure that we don't increase the alignment of the store instruction. Because if we increase it to be "more aligned" than the pointer, code-gen may use instructions which require a greater alignment than the pointer guarantees. <rdar://problem/11043589> llvm-svn: 152907
* In InstCombiner::visitOr, make sure we reverse the operand swap used for ↵Eli Friedman2012-03-161-1/+7
| | | | | | checking for or-of-xor operations after those checks; a later check expects that any constant will be in Op1. PR12234. llvm-svn: 152884
* Use an iterator instead of calling .size() on the worklist every time, which ↵Bill Wendling2012-03-151-2/+2
| | | | | | is wasteful. llvm-svn: 152794
* llvm::SwitchInstStepan Dyatkovskiy2012-03-111-2/+2
| | | | | | | Renamed methods caseBegin, caseEnd and caseDefault with case_begin, case_end, and case_default. Added some notes relative to case iterators. llvm-svn: 152532
* Taken into account Duncan's comments for r149481 dated by 2nd Feb 2012:Stepan Dyatkovskiy2012-03-081-7/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | 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
* Restrict this transformation to equality conditions.Bill Wendling2012-02-291-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This transformation is not correct for not-equal conditions: (trunc x) != C1 & (and x, CA) != C2 -> (and x, CA|CMAX) != C1|C2 Let C1 == 0 C2 == 0 CA == 0xFF0000 CMAX == 0xFF and truncating to i8. The original truth table: x | A: trunc x != 0 | B: x & 0xFF0000 != 0 | A & B != 0 -------------------------------------------------------------- 0x00000 | 0 | 0 | 0 0x00001 | 1 | 0 | 0 0x10000 | 0 | 1 | 0 0x10001 | 1 | 1 | 1 The truth table of the replacement: x | x & 0xFF00FF != 0 ---------------------------- 0x00000 | 0 0x00001 | 1 0x10000 | 1 0x10001 | 1 So they are different. llvm-svn: 151691
* Fix unsigned off-by-one in comment.Benjamin Kramer2012-02-211-1/+1
| | | | llvm-svn: 151056
* InstCombine: Don't transform a signed icmp of two GEPs into a signed compare ↵Benjamin Kramer2012-02-211-0/+8
| | | | | | | | | | | of the indices. This transformation is not safe in some pathological cases (signed icmp of pointers should be an extremely rare thing, but it's valid IR!). Add an explanatory comment. Kudos to Duncan for pointing out this edge case (and not giving up explaining it until I finally got it). llvm-svn: 151055
* InstCombine: Removing the base from the address calculation is only safe ↵Benjamin Kramer2012-02-201-1/+1
| | | | | | when the GEPs are inbounds. llvm-svn: 150978
* InstCombine: When comparing two GEPs that were derived from the same base ↵Benjamin Kramer2012-02-201-0/+14
| | | | | | | | pointer but use different types, expand the offset calculation and to the compare on the offset if profitable. This came up in SmallVector code. llvm-svn: 150962
* InstCombine: Make OptimizePointerDifference more aggressive.Benjamin Kramer2012-02-201-27/+27
| | | | | | | | | - Ignore pointer casts. - Also expand GEPs that aren't constantexprs when they have one use or only constant indices. - We now compile "&foo[i] - &foo[j]" into "i - j". llvm-svn: 150961
* Check against umin while converting fcmp into an icmp.Devang Patel2012-02-131-0/+11
| | | | llvm-svn: 150425
* Convert assert(0) to llvm_unreachableCraig Topper2012-02-072-2/+2
| | | | llvm-svn: 149967
* Remove some dead code and tidy things up now that vectors use ConstantDataVectorChris Lattner2012-02-063-35/+19
| | | | | | instead of always using ConstantVector. llvm-svn: 149912
* [unwind removal] We no longer have 'unwind' instructions being generated, soBill Wendling2012-02-061-2/+1
| | | | | | remove the code that handles them. llvm-svn: 149901
* Make helper static.Benjamin Kramer2012-02-061-3/+3
| | | | llvm-svn: 149865
* Narrow test further. Make bot and test happy.Jim Grosbach2012-02-031-1/+3
| | | | llvm-svn: 149650
* Tidy up. Trailing whitespace.Jim Grosbach2012-02-031-55/+55
| | | | llvm-svn: 149649
* Restrict InstCombine from converting varargs to or from fixed args.Jim Grosbach2012-02-031-0/+7
| | | | | | More targetted fix replacing d0e277d272d517ca1cda368267d199f0da7cad95. llvm-svn: 149648
* Revert "Disable InstCombine unsafe folding bitcasts of calls w/ varargs."Jim Grosbach2012-02-031-5/+14
| | | | | | This reverts commit d0e277d272d517ca1cda368267d199f0da7cad95. llvm-svn: 149647
* SwitchInst refactoring.Stepan Dyatkovskiy2012-02-011-5/+5
| | | | | | | | | | | | | | | | | 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
* Disable InstCombine unsafe folding bitcasts of calls w/ varargs.Jim Grosbach2012-02-011-14/+5
| | | | | | | | | | | Changing arguments from being passed as fixed to varargs is unsafe, as the ABI may require they be handled differently (stack vs. register, for example). Remove two tests which rely on the bitcast being folded into the direct call, which is exactly the transformation that's unsafe. llvm-svn: 149457
* enhance logic to support ConstantDataArray.Chris Lattner2012-01-311-8/+13
| | | | llvm-svn: 149340
* continue making the world safe for ConstantDataVector. At this point,Chris Lattner2012-01-275-35/+60
| | | | | | | we should (theoretically optimize and codegen ConstantDataVector as well as ConstantVector. llvm-svn: 149116
* Continue improving support for ConstantDataAggregate, and use theChris Lattner2012-01-261-16/+8
| | | | | | new methods recently added to (sometimes greatly!) simplify code. llvm-svn: 149024
* some general cleanup, using new methods and tidying up old code.Chris Lattner2012-01-261-69/+26
| | | | llvm-svn: 149006
* use Constant::getAggregateElement to simplify a bunch of code.Chris Lattner2012-01-251-42/+22
| | | | llvm-svn: 148934
* use ConstantVector::getSplat in a few places.Chris Lattner2012-01-252-3/+3
| | | | llvm-svn: 148929
* basic instcombine support for CDS.Chris Lattner2012-01-242-14/+32
| | | | llvm-svn: 148806
* More dead code removal (using -Wunreachable-code)David Blaikie2012-01-203-4/+0
| | | | llvm-svn: 148578
* Extend Attributes to 64 bitsKostya Serebryany2012-01-201-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | Problem: LLVM needs more function attributes than currently available (32 bits). One such proposed attribute is "address_safety", which shows that a function is being checked for address safety (by AddressSanitizer, SAFECode, etc). Solution: - extend the Attributes from 32 bits to 64-bits - wrap the object into a class so that unsigned is never erroneously used instead - change "unsigned" to "Attributes" throughout the code, including one place in clang. - the class has no "operator uint64 ()", but it has "uint64_t Raw() " to support packing/unpacking. - the class has "safe operator bool()" to support the common idiom: if (Attributes attr = getAttrs()) useAttrs(attr); - The CTOR from uint64_t is marked explicit, so I had to add a few explicit CTOR calls - Add the new attribute "address_safety". Doing it in the same commit to check that attributes beyond first 32 bits actually work. - Some of the functions from the Attribute namespace are worth moving inside the class, but I'd prefer to have it as a separate commit. Tested: "make check" on Linux (32-bit and 64-bit) and Mac (10.6) built/run spec CPU 2006 on Linux with clang -O2. This change will break clang build in lib/CodeGen/CGCall.cpp. The following patch will fix it. llvm-svn: 148553
* Move assert to the right place.Benjamin Kramer2012-01-091-1/+1
| | | | llvm-svn: 147779
* InstCombine: Teach foldLogOpOfMaskedICmpsHelper that sign bit tests are bit ↵Benjamin Kramer2012-01-091-81/+82
| | | | | | | | tests. This subsumes several other transforms while enabling us to catch more cases. llvm-svn: 147777
* Tweak my last commit to be less conservative about uses.Benjamin Kramer2012-01-081-25/+23
| | | | | | | We still save an instruction when just the "and" part is replaced. Also change the code to match comments more closely. llvm-svn: 147753
* InstCombine: If we have a bit test and a sign test anded/ored together, ↵Benjamin Kramer2012-01-081-0/+32
| | | | | | | | merge the sign bit into the bit test. This is common in bit field code, e.g. checking if the first or the last bit of a bit field is set. llvm-svn: 147749
* Remove pointless asserts.Nick Lewycky2012-01-041-2/+0
| | | | llvm-svn: 147529
* Teach instcombine all sorts of great stuff about shifts that have exact, nuw orNick Lewycky2012-01-042-8/+59
| | | | | | nsw bits on them. llvm-svn: 147528
* Make use of the exact bit when optimizing '(X >>exact 3) << 1' to eliminate theNick Lewycky2011-12-311-5/+11
| | | | | | | 'and' that would zero out the trailing bits, and to produce an exact shift ourselves. llvm-svn: 147391
* InstCombine: Add a combine that turns (2^n)-1 ^ x back into (2^n)-1 - x iff ↵Benjamin Kramer2011-12-241-0/+13
| | | | | | | | | x is smaller than 2^n and it fuses with a following add. This was intended to undo the sub canonicalization in cases where it's not profitable, but it also finds some cases on it's own. llvm-svn: 147256
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