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* DataLayout is mandatory, update the API to reflect it with references.Mehdi Amini2015-03-101-6/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
* New instcombine rule: max(~a,~b) -> ~min(a, b)Sanjoy Das2015-02-241-21/+5
| | | | | | | | | | This case is interesting because ScalarEvolutionExpander lowers min(a, b) as ~max(~a,~b). I think the profitability heuristics can be made more clever/aggressive, but this is a start. Differential Revision: http://reviews.llvm.org/D7821 llvm-svn: 230285
* InstCombine: Allow folding of xor into icmp by changing the predicate for ↵Benjamin Kramer2015-02-121-3/+4
| | | | | | | | vectors The loop vectorizer can create this pattern. llvm-svn: 228954
* [PM] Rename InstCombine.h to InstCombineInternal.h in preparation forChandler Carruth2015-01-221-1/+1
| | | | | | | | | | | | | | | | creating a non-internal header file for the InstCombine pass. I thought about calling this InstCombiner.h or in some way more clearly associating it with the InstCombiner clas that it is primarily defining, but there are several other utility interfaces defined within this for InstCombine. If, in the course of refactoring, those end up moving elsewhere or going away, it might make more sense to make this the combiner's header alone. Naturally, this is a bikeshed to a certain degree, so feel free to lobby for a different shade of paint if this name just doesn't suit you. llvm-svn: 226783
* [PM] Split the AssumptionTracker immutable pass into two separate APIs:Chandler Carruth2015-01-041-9/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
* InstCombe: Infer nsw for multipliesDavid Majnemer2014-12-261-2/+1
| | | | | | | We already utilize this logic for reducing overflow intrinsics, it makes sense to reuse it for normal multiplies as well. llvm-svn: 224847
* [InstCombine] Minor optimization for bswap with binary opsSimon Pilgrim2014-12-041-0/+64
| | | | | | | | | | | | | | | | | Added instcombine optimizations for BSWAP with AND/OR/XOR ops: OP( BSWAP(x), BSWAP(y) ) -> BSWAP( OP(x, y) ) OP( BSWAP(x), CONSTANT ) -> BSWAP( OP(x, BSWAP(CONSTANT) ) ) Since its just a one liner, I've also added BSWAP to the DAGCombiner equivalent as well: fold (OP (bswap x), (bswap y)) -> (bswap (OP x, y)) Refactored bswap-fold tests to use FileCheck instead of just checking that the bswaps had gone. Differential Revision: http://reviews.llvm.org/D6407 llvm-svn: 223349
* InstCombine: simplify signed range checksErik Eckstein2014-12-031-0/+73
| | | | | | | | | Try to convert two compares of a signed range check into a single unsigned compare. Examples: (icmp sge x, 0) & (icmp slt x, n) --> icmp ult x, n (icmp slt x, 0) | (icmp sgt x, n) --> icmp ugt x, n llvm-svn: 223224
* InstCombine: FoldOrOfICmps harderDavid Majnemer2014-11-281-2/+25
| | | | | | | | | | | | We may be in a situation where the icmps might not be near each other in a tree of or instructions. Try to dig out related compare instructions and see if they combine. N.B. This won't fire on deep trees of compares because rewritting the tree might end up creating a net increase of IR. We may have to resort to something more sophisticated if this is a real problem. llvm-svn: 222928
* InstCombine: Fold away tautological masked comparesDavid Majnemer2014-11-181-1/+1
| | | | | | | | | It is impossible for (x & INT_MAX) == 0 && x == INT_MAX to ever be true. While this sort of reasoning should normally live in InstSimplify, the machinery that derives this result is not trivial to split out. llvm-svn: 222230
* InstCombine: Clean up foldLogOpOfMaskedICmpsDavid Majnemer2014-11-181-16/+14
| | | | | | No functional change intended. llvm-svn: 222229
* InstCombine: Turn (x != 0 & x <u C) into the canonical range check form (x-1 ↵Benjamin Kramer2014-10-121-0/+2
| | | | | | <u C-1) llvm-svn: 219585
* Make use of @llvm.assume in ValueTracking (computeKnownBits, etc.)Hal Finkel2014-09-071-21/+29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
* InstCombine: Remove a special case patternDavid Majnemer2014-09-051-15/+18
| | | | | | | The special case did not work when run under -reassociate and can easily be expressed by a further generalization of an existing pattern. llvm-svn: 217227
* InstCombine: Try harder to combine icmp instructionsDavid Majnemer2014-08-301-3/+25
| | | | | | | | | | | | | consider: (and (icmp X, Y), (and Z, (icmp A, B))) It may be possible to combine (icmp X, Y) with (icmp A, B). If we successfully combine, create an 'and' instruction with Z. This fixes PR20814. N.B. There is room for improvement after this change but I'm not convinced it's worth chasing yet. llvm-svn: 216814
* This patch enables SimplifyUsingDistributiveLaws() to handle following pattens.Dinesh Dwivedi2014-08-261-39/+0
| | | | | | | | | | | | (X >> Z) & (Y >> Z) -> (X&Y) >> Z for all shifts. (X >> Z) | (Y >> Z) -> (X|Y) >> Z for all shifts. (X >> Z) ^ (Y >> Z) -> (X^Y) >> Z for all shifts. These patterns were previously handled separately in visitAnd()/visitOr()/visitXor(). Differential Revision: http://reviews.llvm.org/D4951 llvm-svn: 216443
* InstCombine: Fold ((A | B) & C1) ^ (B & C2) -> (A & C1) ^ B if C1^C2=-1David Majnemer2014-08-211-0/+44
| | | | | | Adapted from a patch by Richard Smith, test-case written by me. llvm-svn: 216157
* New InstCombine pattern: (icmp ult/ule (A + C1), C3) | (icmp ult/ule (A + ↵Yi Jiang2014-08-201-0/+55
| | | | | | C2), C3) to (icmp ult/ule ((A & ~(C1 ^ C2)) + max(C1, C2)), C3) under certain condition llvm-svn: 216135
* InstCombine: ((A & ~B) ^ (~A & B)) to A ^ BMayur Pandey2014-08-191-0/+10
| | | | | | | | | | | | | Proof using CVC3 follows: $ cat t.cvc A, B : BITVECTOR(32); QUERY BVXOR((A & ~B),(~A & B)) = BVXOR(A,B); $ cvc3 t.cvc Valid. Differential Revision: http://reviews.llvm.org/D4898 llvm-svn: 215974
* test commit (spelling correction)Mayur Pandey2014-08-191-1/+1
| | | | llvm-svn: 215970
* InstCombine: ((A | ~B) ^ (~A | B)) to A ^ BDavid Majnemer2014-08-141-0/+10
| | | | | | | | | | | | | | | Proof using CVC3 follows: $ cat t.cvc A, B : BITVECTOR(32); QUERY BVXOR((A | ~B),(~A |B)) = BVXOR(A,B); $ cvc3 t.cvc Valid. Patch by Mayur Pandey! Differential Revision: http://reviews.llvm.org/D4883 llvm-svn: 215621
* Added InstCombine Transform for ((B | C) & A) | B -> B | (A & C)David Majnemer2014-08-141-0/+4
| | | | | | | | | | | | Transform ((B | C) & A) | B --> B | (A & C) Z3 Link: http://rise4fun.com/Z3/hP6p Patch by Sonam Kumari! Differential Revision: http://reviews.llvm.org/D4865 llvm-svn: 215619
* InstCombine: Combine (xor (or %a, %b) (xor %a, %b)) to (add %a, %b)Karthik Bhat2014-08-131-0/+12
| | | | | | | | | | | | | Correctness proof of the transform using CVC3- $ cat t.cvc A, B : BITVECTOR(32); QUERY BVXOR(A | B, BVXOR(A,B) ) = A & B; $ cvc3 t.cvc Valid. llvm-svn: 215524
* This patch implements transform for pattern "(A & ~B) ^ (~A) -> ~(A & B)".Suyog Sarda2014-08-011-0/+5
| | | | | | Differential Revision: http://reviews.llvm.org/D4653 llvm-svn: 214479
* This patch implements transform for pattern "(A | B) & ((~A) ^ B) -> (A & B)".Suyog Sarda2014-08-011-0/+10
| | | | | | Differential Revision: http://reviews.llvm.org/D4628 llvm-svn: 214478
* This patch implements transform for pattern "( A & (~B)) | (A ^ B) -> (A ^ B)"Suyog Sarda2014-08-011-0/+10
| | | | | | Differential Revision: http://reviews.llvm.org/D4652 llvm-svn: 214477
* This patch implements transform for pattern "(A & B) | ((~A) ^ B) -> (~A ^ B)".Suyog Sarda2014-08-011-0/+10
| | | | | | | | Patch Credit to Ankit Jain ! Differential Revision: http://reviews.llvm.org/D4655 llvm-svn: 214476
* InstCombine: Simplify (A ^ B) or/and (A ^ B ^ C)David Majnemer2014-07-301-0/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | While we can already transform A | (A ^ B) into A | B, things get bad once we have (A ^ B) | (A ^ B ^ Cst) because reassociation will morph this into (A ^ B) | ((A ^ Cst) ^ B). Our existing patterns fail once this happens. To fix this, we add a new pattern which looks through the tree of xor binary operators to see that, in fact, there exists a redundant xor operation. What follows bellow is a correctness proof of the transform using CVC3. $ cat t.cvc A, B, C : BITVECTOR(64); QUERY BVXOR(A, B) | BVXOR(BVXOR(B, C), A) = BVXOR(A, B) | C; QUERY BVXOR(BVXOR(A, C), B) | BVXOR(A, B) = BVXOR(A, B) | C; QUERY BVXOR(A, B) & BVXOR(BVXOR(B, C), A) = BVXOR(A, B) & ~C; QUERY BVXOR(BVXOR(A, C), B) & BVXOR(A, B) = BVXOR(A, B) & ~C; $ cvc3 < t.cvc Valid. Valid. Valid. Valid. llvm-svn: 214342
* Added InstCombine transform for pattern "(A & B) ^ (A ^ B) -> (A | B)"Suyog Sarda2014-07-221-0/+8
| | | | | | | | Patch idea by Ankit Jain ! Differential Revision: http://reviews.llvm.org/D4618 llvm-svn: 213677
* Added InstCombine Transform for patterns: Suyog Sarda2014-07-221-0/+10
| | | | | | | | | | "((~A & B) | A) -> (A | B)" and "((A & B) | ~A) -> (~A | B)" Original Patch credit to Ankit Jain !! Differential Revision: http://reviews.llvm.org/D4591 llvm-svn: 213676
* This patch implements transform for pattern "(A | B) ^ (~A) -> (A | ~B)".Suyog Sarda2014-07-221-0/+6
| | | | | | | | Patch Credit to Ankit Jain !! Differential Revision: http://reviews.llvm.org/D4588 llvm-svn: 213662
* Move optimization of some cases of (A & C1)|(B & C2) from instcombine to ↵Nick Lewycky2014-06-191-23/+0
| | | | | | instsimplify. Patch by Rahul Jain, plus some last minute changes by me -- you can blame me for any bugs. llvm-svn: 211252
* Reorder shuffle and binary operation.Serge Pavlov2014-05-111-0/+9
| | | | | | | | | | | | | This patch enables transformations: BinOp(shuffle(v1), shuffle(v2)) -> shuffle(BinOp(v1, v2)) BinOp(shuffle(v1), const1) -> shuffle(BinOp, const2) They allow to eliminate extra shuffles in some cases. Differential Revision: http://reviews.llvm.org/D3525 llvm-svn: 208488
* [C++] Use 'nullptr'. Transforms edition.Craig Topper2014-04-251-69/+69
| | | | 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
* [Modules] Sink all the DEBUG_TYPE defines for InstCombine out of theChandler Carruth2014-04-211-0/+1
| | | | | | | | | | | header files and into the cpp files. These files will require more touches as the header files actually use DEBUG(). Eventually, I'll have to introduce a matched #define and #undef of DEBUG_TYPE for the header files, but that comes as step N of many to clean all of this up. llvm-svn: 206777
* [Modules] Move the ConstantRange class into the IR library. This isChandler Carruth2014-03-041-1/+1
| | | | | | | | | | a bit surprising, as the class is almost entirely abstracted away from any particular IR, however it encodes the comparsion predicates which mutate ranges as ICmp predicate codes. This is reasonable as they're used for both instructions and constants. Thus, it belongs in the IR library with instructions and constants. llvm-svn: 202838
* [Modules] Move the LLVM IR pattern match header into the IR library, itChandler Carruth2014-03-041-1/+1
| | | | | | obviously is coupled to the IR. llvm-svn: 202818
* Rename many DataLayout variables from TD to DL.Rafael Espindola2014-02-211-3/+3
| | | | | | | | | 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
* InstCombine: Teach icmp merging about the equivalence of bit tests and ↵Benjamin Kramer2014-02-111-23/+38
| | | | | | | | | UGE/ULT with a power of 2. This happens in bitfield code. While there reorganize the existing code a bit. llvm-svn: 201176
* InstCombine: Hoist 3 copies of AddOne/SubOne into a header.Benjamin Kramer2014-01-191-10/+0
| | | | llvm-svn: 199605
* InstCombine: Replace a hand-rolled version of isKnownToBeAPowerOfTwo with ↵Benjamin Kramer2014-01-191-21/+4
| | | | | | the real thing. llvm-svn: 199604
* Update the docs to match the function name.Nadav Rotem2013-11-131-1/+1
| | | | llvm-svn: 194537
* Fold (iszero(A&K1) | iszero(A&K2)) -> (A&(K1|K2)) != (K1|K2) if we know ↵Nadav Rotem2013-11-121-3/+50
| | | | | | that K1 and K2 are 'one-hot' (only one bit is on). llvm-svn: 194525
* InstCombine: allow unmasked icmps to be combined with logical opsTim Northover2013-09-041-9/+29
| | | | | | | | | | "(icmp op i8 A, B)" is equivalent to "(icmp op i8 (A & 0xff), B)" as a degenerate case. Allowing this as a "masked" comparison when analysing "(icmp) &/| (icmp)" allows us to combine them in more cases. rdar://problem/7625728 llvm-svn: 189931
* InstCombine: look for masked compares with subset relationTim Northover2013-09-041-11/+75
| | | | | | | | | | | Even in cases which aren't universally optimisable like "(A & B) != 0 && (A & C) != 0", the masks can make one of the comparisons completely redundant. In this case, since we've gone to the effort of spotting masked comparisons we should combine them. rdar://problem/7625728 llvm-svn: 189930
* InstCombine: Use isAllOnesValue() instead of explicit -1.Jim Grosbach2013-08-161-1/+1
| | | | llvm-svn: 188563
* InstCombine: Simplify if(x!=0 && x!=-1).Jim Grosbach2013-08-161-1/+6
| | | | | | | | | | | When both constants are positive or both constants are negative, InstCombine already simplifies comparisons like this, but when it's exactly zero and -1, the operand sorting ends up reversed and the pattern fails to match. Handle that special case. Follow up for rdar://14689217 llvm-svn: 188512
* Use SmallVectorImpl& instead of SmallVector to avoid repeating small vector ↵Craig Topper2013-07-141-1/+1
| | | | | | size. llvm-svn: 186274
* InstCombine: (icmp eq B, 0) | (icmp ult A, B) -> (icmp ule A, B-1)David Majnemer2013-07-051-1/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | This transform allows us to turn IR that looks like: %1 = icmp eq i64 %b, 0 %2 = icmp ult i64 %a, %b %3 = or i1 %1, %2 ret i1 %3 into: %0 = add i64 %b, -1 %1 = icmp uge i64 %0, %a ret i1 %1 which means we go from lowering: cmpq %rsi, %rdi setb %cl testq %rsi, %rsi sete %al orb %cl, %al ret to lowering: decq %rsi cmpq %rdi, %rsi setae %al ret llvm-svn: 185677
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