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* Address some review comments from Duncan. This moves the iterativeChandler Carruth2012-03-131-32/+23
| | | | | | | | | | | | | | | | | | | offset accumulation to use a boring APInt instead of ConstantExprs. I didn't go all the way to an 'int64_t' because I wanted APInt to handle any magic required to properly wrap the arithmetic when the pointer width is <64 bits. If there is a significant penalty from using APInt here, first off WTF, and secondly let me know and I'll do the math by hand. I've left one layer still operating w/ ConstantExpr because it makes the interface quite a bit simpler, and that one isn't iterative so has much lower cost. I suppose this may potentially speed up some strang compilation situations, but I don't really expect much. It should have no functional impact either way. llvm-svn: 152590
* Teach instsimplify how to constant fold pointer differences.Chandler Carruth2012-03-121-0/+122
| | | | | | | | | | | | | | | | | | | Typically instcombine has handled this, but pointer differences show up in several contexts where we would like to get constant folding, and cannot afford to run instcombine. Specifically, I'm working on improving the constant folding of arguments used in inline cost analysis with instsimplify. Doing this in instsimplify implies some algorithm changes. We have to handle multiple layers of all-constant GEPs because instsimplify cannot fold them into a single GEP the way instcombine can. Also, we're only interested in all-constant GEPs. The result is that this doesn't really replace the instcombine logic, it's just complimentary and focused on constant folding. Reviewed on IRC by Benjamin Kramer. llvm-svn: 152555
* As Duncan pointed out, pointers tend not to be in floating point ↵Bill Wendling2012-03-101-6/+6
| | | | | | format...for now. llvm-svn: 152499
* Make this transformation slightly less agressive and more correct.Bill Wendling2012-03-101-8/+18
| | | | | | | | | | | The 'CmpInst::isFalseWhenEqual' function returns 'false' for values other than simply equality. For instance, it returns 'false' for <= or >=. This isn't the correct behavior for this transformation, which is checking for strict equality and non-equality. It was causing the gcc.c-torture/execute/frame-address.c test to fail because it would completely (and incorrectly) optimize a whole function into a 'ret i32 0'. llvm-svn: 152497
* Refactor some methods to look through bitcasts and GEPs on pointers intoChandler Carruth2012-03-101-25/+3
| | | | | | | | | | a common collection of methods on Value, and share their implementation. We had two variations in two different places already, and I need the third variation for inline cost estimation. Reviewed by Duncan Sands on IRC, but further comments here welcome. llvm-svn: 152490
* Reinstate the optimization from r151449 with a fix to not turn 'gep %x' intoNick Lewycky2012-02-261-11/+51
| | | | | | 'gep null' when the icmp predicate is unsigned (or is signed without inbounds). llvm-svn: 151467
* Don't call dominates on unreachable instructions.Rafael Espindola2012-02-261-1/+2
| | | | llvm-svn: 151466
* Roll these back to r151448 until I figure out how they're breakingNick Lewycky2012-02-251-42/+10
| | | | | | MultiSource/Applications/lua. llvm-svn: 151463
* An argument and a local identified object (eg. a noalias call) could turn outNick Lewycky2012-02-251-12/+13
| | | | | | | equal if both are null. In the test, scope type %t and global @y by adding a 'gep' prefix to them. llvm-svn: 151452
* Fix five-letter typo in comment.Nick Lewycky2012-02-251-1/+1
| | | | llvm-svn: 151450
* Teach instsimplify to be more aggressive when analyzing comparisons of pointersNick Lewycky2012-02-251-10/+41
| | | | | | | by using llvm::isIdentifiedObject. Also teach it to handle GEPs that have the same base pointer and constant operands. Fixes PR11238! llvm-svn: 151449
* fix PR12075, a regression in a recent transform I added. In unreachable ↵Chris Lattner2012-02-241-4/+18
| | | | | | code, gep chains can be infinite. Just like "stripPointerCasts", use a set to keep track of visited instructions so we don't recurse infinitely. llvm-svn: 151383
* fold comparisons of gep'd alloca points with null to false,Chris Lattner2012-02-201-4/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | implementing PR12013. We now compile the testcase to: __Z4testv: ## @_Z4testv ## BB#0: ## %_ZN4llvm15SmallVectorImplIiE9push_backERKi.exit pushq %rbx subq $64, %rsp leaq 32(%rsp), %rbx movq %rbx, (%rsp) leaq 64(%rsp), %rax movq %rax, 16(%rsp) movl $1, 32(%rsp) leaq 36(%rsp), %rax movq %rax, 8(%rsp) leaq (%rsp), %rdi callq __Z1gRN4llvm11SmallVectorIiLj8EEE movq (%rsp), %rdi cmpq %rbx, %rdi je LBB0_2 ## BB#1: callq _free LBB0_2: ## %_ZN4llvm11SmallVectorIiLj8EED1Ev.exit addq $64, %rsp popq %rbx ret instead of: __Z4testv: ## @_Z4testv ## BB#0: pushq %rbx subq $64, %rsp xorl %eax, %eax leaq (%rsp), %rbx addq $32, %rbx movq %rbx, (%rsp) movq %rbx, 8(%rsp) leaq 64(%rsp), %rcx movq %rcx, 16(%rsp) je LBB0_2 ## BB#1: movl $1, 32(%rsp) movq %rbx, %rax LBB0_2: ## %_ZN4llvm15SmallVectorImplIiE9push_backERKi.exit addq $4, %rax movq %rax, 8(%rsp) leaq (%rsp), %rdi callq __Z1gRN4llvm11SmallVectorIiLj8EEE movq (%rsp), %rdi cmpq %rbx, %rdi je LBB0_4 ## BB#3: callq _free LBB0_4: ## %_ZN4llvm11SmallVectorIiLj8EED1Ev.exit addq $64, %rsp popq %rbx ret This doesn't shrink clang noticably though. llvm-svn: 150944
* Fix a rather nasty regression from r150690: LHS != RHS does not imply ↵Eli Friedman2012-02-181-1/+2
| | | | | | LHS->stripPointerCasts() != RHS->stripPointerCasts(). llvm-svn: 150863
* Revert "InstSimplify: Strip pointer casts early."Benjamin Kramer2012-02-161-6/+5
| | | | | | | Turns out this isn't safe, because the code below depends on LHS and RHS having the same type. llvm-svn: 150695
* InstSimplify: Strip pointer casts early.Benjamin Kramer2012-02-161-5/+6
| | | | llvm-svn: 150694
* InstSimplify: Ignore pointer casts when constant folding compares between ↵Benjamin Kramer2012-02-161-2/+5
| | | | | | pointers. llvm-svn: 150690
* Fix PR11948: the result type of an icmp may be a vector of boolean -Duncan Sands2012-02-101-0/+5
| | | | | | don't assume it is a boolean. llvm-svn: 150247
* Convert assert(0) to llvm_unreachableCraig Topper2012-02-071-6/+3
| | | | llvm-svn: 149967
* PatternMatch: Introduce a matcher for instructions with the "exact" bit. Use ↵Benjamin Kramer2012-01-011-10/+5
| | | | | | it to simplify a few matchers. llvm-svn: 147403
* Add support for vectors of pointers.Nadav Rotem2011-12-051-2/+5
| | | | llvm-svn: 145801
* Propagate TargetLibraryInfo throughout ConstantFolding.cpp and Chad Rosier2011-12-011-217/+307
| | | | | | | InstructionSimplify.cpp. Other fixups as needed. Part of rdar://10500969 llvm-svn: 145559
* Make use of "getScalarType()". No functionality change.Nick Lewycky2011-12-011-8/+3
| | | | llvm-svn: 145556
* Fix code to match comment. Fixes PR11340, a regression from r143209.Eli Friedman2011-11-081-1/+1
| | | | llvm-svn: 144121
* Teach instsimplify to simplify calls to undef.Dan Gohman2011-11-041-0/+11
| | | | llvm-svn: 143719
* Reapply commit 143214 with a fix: m_ICmp doesn't match conditionsDuncan Sands2011-10-301-29/+65
| | | | | | | | | | | | with the given predicate, it matches any condition and returns the predicate - d'oh! Original commit message: The expression icmp eq (select (icmp eq x, 0), 1, x), 0 folds to false. Spotted by my super-optimizer in 186.crafty and 450.soplex. We really need a proper infrastructure for handling generalizations of this kind of thing (which occur a lot), however this case is so simple that I decided to go ahead and implement it directly. llvm-svn: 143318
* Revert r143214; it's breaking a bunch of stuff.Eli Friedman2011-10-291-45/+29
| | | | llvm-svn: 143265
* The expression icmp eq (select (icmp eq x, 0), 1, x), 0 folds to false.Duncan Sands2011-10-281-29/+45
| | | | | | | | | Spotted by my super-optimizer in 186.crafty and 450.soplex. We really need a proper infrastructure for handling generalizations of this kind of thing (which occur a lot), however this case is so simple that I decided to go ahead and implement it directly. llvm-svn: 143214
* Fold icmp ugt (udiv X, Y), X to false. Spotted by my super-optimizerDuncan Sands2011-10-281-0/+12
| | | | | | in 186.crafty. llvm-svn: 143209
* Reapply commit 143028 with a fix: the problem was casting a ConstantExpr MulDuncan Sands2011-10-271-2/+3
| | | | | | | | | | | using BinaryOperator (which only works for instructions) when it should have been a cast to OverflowingBinaryOperator (which also works for constants). While there, correct a few other dubious looking uses of BinaryOperator. Thanks to Chad Rosier for the testcase. Original commit message: My super-optimizer noticed that we weren't folding this expression to true: (x *nsw x) sgt 0, where x = (y | 1). This occurs in 464.h264ref. llvm-svn: 143125
* The maximum power of 2 dividing a power of 2 is itself. This occursDuncan Sands2011-10-261-0/+9
| | | | | | in 403.gcc and was spotted by my super-optimizer. llvm-svn: 143054
* InstSimplify: Don't try to replace an extractvalue/insertvalue pair with the ↵Benjamin Kramer2011-09-051-1/+2
| | | | | | | | original value if types don't match. Fixes clang selfhost. llvm-svn: 139120
* Add some simple insertvalue simplifications, for the purpose of cleaningDuncan Sands2011-09-051-0/+36
| | | | | | up do-nothing exception handling code produced by dragonegg. llvm-svn: 139113
* Revert r137781; I agree with Duncan's comment that the situation in question ↵Eli Friedman2011-08-171-5/+4
| | | | | | is clearly impossible given the current structure of the code. llvm-svn: 137853
* Extend the undef ^ undef idiom once more. No testcase: I can't figure out ↵Eli Friedman2011-08-161-4/+5
| | | | | | how to actually trigger the codepath in question at the moment, but it might get exposed in the future. llvm-svn: 137781
* Fix what seems an obvious typo. Patch by Ivan Krasin. ProblemDuncan Sands2011-08-041-1/+1
| | | | | | reported at http://habrahabr.ru/blogs/compilers/125626/. llvm-svn: 136865
* Add helper function for getting true/false constants in a uniformDuncan Sands2011-07-261-34/+48
| | | | | | | way for i1 and vector of i1 types. Use these to make some code more self-documenting. llvm-svn: 136079
* Convert GetElementPtrInst to use ArrayRef.Jay Foad2011-07-251-2/+1
| | | | llvm-svn: 135904
* Convert ConstantExpr::getGetElementPtr andJay Foad2011-07-211-3/+1
| | | | | | ConstantExpr::getInBoundsGetElementPtr to use ArrayRef. llvm-svn: 135673
* Convert SimplifyGEPInst to use ArrayRef.Jay Foad2011-07-191-8/+9
| | | | llvm-svn: 135482
* Use ArrayRef in ConstantFoldInstOperands and ConstantFoldCall.Jay Foad2011-07-191-10/+10
| | | | llvm-svn: 135477
* land David Blaikie's patch to de-constify Type, with a few tweaks.Chris Lattner2011-07-181-9/+9
| | | | llvm-svn: 135375
* Improve constant folding of undef for cmp and select operators.Dan Gohman2011-07-011-4/+4
| | | | llvm-svn: 134223
* The comparision "max(x,y)==x" is equivalent to "x>=y". Since the max isDuncan Sands2011-05-071-10/+56
| | | | | | | often expressed as "x >= y ? x : y", there is a good chance we can extract the existing "x >= y" from it and use that as a replacement for "max(x,y)==x". llvm-svn: 131049
* PR9838: Fix transform introduced in r127064 to not trigger when only one ↵Eli Friedman2011-05-051-1/+1
| | | | | | side of the icmp is an exact shift. llvm-svn: 130954
* Add variations on: max(x,y) >= min(x,z) folds to true. This isn't that common,Duncan Sands2011-05-041-2/+46
| | | | | | | | but according to my super-optimizer there are only two missed simplifications of -instsimplify kind when compiling bzip2, and this is one of them. It amuses me to have bzip2 be perfectly optimized as far as instsimplify goes! llvm-svn: 130840
* Implement some basic simplifications involving min/max, for exampleDuncan Sands2011-05-031-0/+118
| | | | | | | | max(a,b) >= a -> true. According to my super-optimizer, these are by far the most common simplifications (of the -instsimplify kind) that occur in the testsuite and aren't caught by -std-compile-opts. llvm-svn: 130780
* Fix PR9579: when simplifying a compare to "true" or "false", and it wasDuncan Sands2011-05-021-18/+22
| | | | | | a vector compare, generate a vector result rather than i1 (and crashing). llvm-svn: 130706
* Move some rem transforms out of instcombine and into instsimplify.Duncan Sands2011-05-021-0/+117
| | | | | | | This automagically provides a transform noticed by my super-optimizer as occurring quite often: "rem x, (select cond, x, 1)" -> 0. llvm-svn: 130694
* Don't include Operator.h from InstrTypes.h.Jay Foad2011-04-111-0/+1
| | | | llvm-svn: 129271
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