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2012-03-28Revert r153521 as it's causing large regressions on the nightly testers.Chad Rosier
Original commit message for r153521 (aka r153423): Use the new range metadata in computeMaskedBits and add a new optimization to instruction simplify that lets us remove an and when loding a boolean value. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153587 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-27Reapply r153423; the original commit was fine. The failing test, distray, had Chad Rosier
undefined behavior, which Rafael was kind enough to fix. Original commit message for r153423: Use the new range metadata in computeMaskedBits and add a new optimization to instruction simplify that lets us remove an and when loding a boolean value. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153521 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-26SCEV fix: Handle loop invariant loads.Andrew Trick
Fixes PR11882: NULL dereference in ComputeLoadConstantCompareExitLimit. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153480 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-26Revert r153423 as this is causing failures on our internal nightly testers.Chad Rosier
Original commit message: Use the new range metadata in computeMaskedBits and add a new optimization to instruction simplify that lets us remove an and when loading a boolean value. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153452 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-26Use the new range metadata in computeMaskedBits and add a new optimization toRafael Espindola
instruction simplify that lets us remove an and when loding a boolean value. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153423 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-25Teach instsimplify how to simplify comparisons of pointers which areChandler Carruth
constant-offsets of a common base using the generic GEP-walking logic I added for computing pointer differences in the same situation. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153419 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-25Switch the pointer-difference simplification logic to only work withChandler Carruth
inbounds GEPs. This isn't really necessary for simplifying pointer differences, but I'm planning to re-use the same code to simplify pointer comparisons where it is necessary. Since real code almost exclusively uses inbounds GEPs, it doesn't seem worth it to support the extra complexity of turning it on and off. If anyone would like that back, feel free to shout. Note that instcombine will still catch any of these patterns. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153418 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-24Try to harden the recursive simplification still further. This is againChandler Carruth
spotted by inspection, and I've crafted no test case that triggers it on my machine, but some of the windows builders are hitting what looks like memory corruption, so *something* is amiss here. This patch takes a more generalized approach to eliminating double-visits. Imagine code such as: %x = ... %y = add %x, 1 %z = add %x, %y You can imagine that if we simplify %x, we would add %y and %z to the list. If the use-chain order happens to cause us to add them in reverse order, we could pull %y off first, and simplify it, adding %z to the list. We now have %z on the list twice, and will reference it after it is deleted. Currently, all my test cases happen to not trigger this, likely due to the use-chain ordering, but there seems no guarantee that such a situation could not occur, so we should handle it correctly. Again, if anyone knows how to craft a testcase that actually triggers this, please let me know. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153397 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-24Don't add the instruction about to be RAUW'ed and erased to theChandler Carruth
worklist. This can happen in theory when an instruction uses itself, such as a PHI node. This was spotted by inspection, and unfortunately I've not been able to come up with a test case that would trigger it. If anyone has ideas, let me know... git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153396 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-24Refactor the interface to recursively simplifying instructions to be tadChandler Carruth
bit simpler by handling a common case explicitly. Also, refactor the implementation to use a worklist based walk of the recursive users, rather than trying to use value handles to detect and recover from RAUWs during the recursive descent. This fixes a very subtle bug in the previous implementation where degenerate control flow structures could cause mutually recursive instructions (PHI nodes) to collapse in just such a way that From became equal to To after some amount of recursion. At that point, we hit the inf-loop that the assert at the top attempted to guard against. This problem is defined away when not using value handles in this manner. There are lots of comments claiming that the WeakVH will protect against just this sort of error, but they're not accurate about the actual implementation of WeakVHs, which do still track RAUWs. I don't have any test case for the bug this fixes because it requires running the recursive simplification on unreachable phi nodes. I've no way to either run this or easily write an input that triggers it. It was found when using instruction simplification inside the inliner when running over the nightly test-suite. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153393 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-23Take out the debug info probe stuff. It's making some changes toEric Christopher
the PassManager annoying and should be reimplemented as a decorator on top of existing passes (as should the timing data). git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153305 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-22Cleanup IVUsers::addUsersIfInteresting.Andrew Trick
Keep the public interface clean, even though LLVM proper does not currently use it. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153263 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-21Teach instsimplify to gracefully degrade in the presence of instructionsChandler Carruth
not attched to a basic block or function. There are conservatively correct answers in these cases, and this makes the analysis more useful in contexts where we have a partially formed bit of IR. I don't have any way to test this directly... suggestions welcome here, but I'm not seeing anything sadly. I only found this using a subsequent patch to the inliner which runs instsimplify on partially inlined instructions, and even then only on a quite large program. I never got a reasonable testcase out of it, and anything I do get is likely to be quite fragile due to requiring an interaction of two different passes, and the only result being a segfault if it goes wrong. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153176 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-20LSR: teach isSimplifiedLoopNest to handle PHI IVUsers.Andrew Trick
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153132 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-20LSR: fix IVUsers isSimplifiedLoopNest to perform a full domtree walkAndrew Trick
instead of skipping the current loop. My prior fix was incomplete because of an overzealous compile-time optimization: Better fix for: <rdar://problem/11049788> Segmentation fault: 11 in LoopStrengthReduce git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153131 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-18Factor out the multiply analysis code in ComputeMaskedBits and apply it to theNick Lewycky
overflow checking multiply intrinsic as well. Add a test for this, updating the test from grep to FileCheck. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153028 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-16Start removing the use of an ad-hoc 'never inline' set and insteadChandler Carruth
directly query the function information which this set was representing. This simplifies the interface of the inline cost analysis, and makes the always-inline pass significantly more efficient. Previously, always-inline would first make a single set of every function in the module *except* those marked with the always-inline attribute. It would then query this set at every call site to see if the function was a member of the set, and if so, refuse to inline it. This is quite wasteful. Instead, simply check the function attribute directly when looking at the callsite. The normal inliner also had similar redundancy. It added every function in the module with the noinline attribute to its set to ignore, even though inside the cost analysis function we *already tested* the noinline attribute and produced the same result. The only tricky part of removing this is that we have to be able to correctly remove only the functions inlined by the always-inline pass when finalizing, which requires a bit of a hack. Still, much less of a hack than the set of all non-always-inline functions was. While I was touching this function, I switched a heavy-weight set to a vector with sort+unique. The algorithm already had a two-phase insert and removal pattern, we were just needlessly paying the uniquing cost on every insert. This probably speeds up some compiles by a small amount (-O0 compiles with lots of always-inline, so potentially heavy libc++ users), but I've not tried to measure it. I believe there is no functional change here, but yell if you spot one. None are intended. Finally, the direction this is going in is to greatly simplify the inline cost query interface so that we can replace its implementation with a much more clever one. Along the way, all the APIs get simplified, so it seems incrementally good. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152903 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-16Pull the implementation of the code metrics out of the inline costChandler Carruth
analysis implementation. The header was already separated. Also cleanup all the comments in the header to follow a nice modern doxygen form. There is still plenty of cruft here, but some of that will fall out in subsequent refactorings and this was an easy step in the right direction. No functionality changed here. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152898 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-16LSR fix: Add isSimplifiedLoopNest to IVUsers analysis.Andrew Trick
Only record IVUsers that are dominated by simplified loop headers. Otherwise SCEVExpander will crash while looking for a preheader. I previously tried to work around this in LSR itself, but that was insufficient. This way, LSR can continue to run if some uses are not in simple loops, as long as we don't attempt to analyze those users. Fixes <rdar://problem/11049788> Segmentation fault: 11 in LoopStrengthReduce git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152892 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-16Do the right thing on NULL uint64 fields.Eric Christopher
Patch by Clemens Hammacher! Fixes PR12243 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152880 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-15Type sizes and fields offsets inside structs are unsigned. This is a highlyDuncan Sands
theoretical fix since it only matters for types with >= 2^63 bits (!) and also only matters if pointers have more than 64 bits, which is not supported anyway. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152831 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-15Make the swap code here a bit more obvious what its doing... We'reChandler Carruth
essentially sorting the pair's arguments. I'd love to actually call sort here, but I'm just not that crazy. ;] git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152764 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-15Don't assume that the arguments are processed in some particular order.Chandler Carruth
This appears to not be the case with dragonegg at least in some contexts. Hopefully will fix the bootstrap assert failure there. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152763 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-15Remove all remnants of partial specialization in the cost computationChandler Carruth
side of things. This is all dead code. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152759 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-14Extend the inline cost calculation to account for bonuses due toChandler Carruth
correlated pairs of pointer arguments at the callsite. This is designed to recognize the common C++ idiom of begin/end pointer pairs when the end pointer is a constant offset from the begin pointer. With the C-based idiom of a pointer and size, the inline cost saw the constant size calculation, and this provides the same level of information for begin/end pairs. In order to propagate this information we have to search for candidate operations on a pair of pointer function arguments (or derived from them) which would be simplified if the pointers had a known constant offset. Then the callsite analysis looks for such pointer pairs in the argument list, and applies the appropriate bonus. This helps LLVM detect that half of bounds-checked STL algorithms (such as hash_combine_range, and some hybrid sort implementations) disappear when inlined with a constant size input. However, it's not a complete fix due the inaccuracy of our cost metric for constants in general. I'm looking into that next. Benchmarks showed no significant code size change, and very minor performance changes. However, specific code such as hashing is showing significantly cleaner inlining decisions. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152752 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-14Refactor the inline cost bonus calculation for constants to useChandler Carruth
a worklist rather than a recursive call. No functionality changed. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152706 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-13enhance jump threading to preserve TBAA information when PRE'ing loads,Chris Lattner
fixing rdar://11039258, an issue that came up when inspecting clang's bootstrapped codegen. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152635 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-13Generalize the "trunc(ptrtoint(x)) - trunc(ptrtoint(y)) ->Duncan Sands
trunc(ptrtoint(x-y))" optimization introduced by Chandler. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152626 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-13Uniformize the InstructionSimplify interface by ensuring that all routinesDuncan Sands
take a TargetLibraryInfo parameter. Internally, rather than passing TD, TLI and DT parameters around all over the place, introduce a struct for holding them. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152623 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-13Fix regression from r151466: an we can't replace uses of an instruction ↵Eli Friedman
reachable from the entry block with uses of an instruction not reachable from the entry block. PR12231. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152595 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-13Address some review comments from Duncan. This moves the iterativeChandler Carruth
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. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152590 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-12Teach instsimplify how to constant fold pointer differences.Chandler Carruth
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. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152555 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-11llvm::SwitchInstStepan Dyatkovskiy
Renamed methods caseBegin, caseEnd and caseDefault with case_begin, case_end, and case_default. Added some notes relative to case iterators. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152532 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-10Make helper static, so it can be inlined into its sole caller.Benjamin Kramer
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152515 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-10As Duncan pointed out, pointers tend not to be in floating point ↵Bill Wendling
format...for now. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152499 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-10Make this transformation slightly less agressive and more correct.Bill Wendling
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'. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152497 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-10Refactor some methods to look through bitcasts and GEPs on pointers intoChandler Carruth
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. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152490 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-09Factor out the analysis of addition and subtraction in ComputeMaskedBits. ReuseNick Lewycky
it to analyze extractvalue(llvm.[us](add|sub).with.overflow.*) intrinsics! git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152398 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-09Undo a previous restriction on the inline cost calculation which NickChandler Carruth
introduced. Specifically, there are cost reductions for all constant-operand icmp instructions against an alloca, regardless of whether the alloca will in fact be elligible for SROA. That means we don't want to abort the icmp reduction computation when we abort the SROA reduction computation. That in turn frees us from the need to keep a separate worklist and defer the ICmp calculations. Use this new-found freedom and some judicious function boundaries to factor the innards of computing the cost factor of any given instruction out of the loop over the instructions and into static helper functions. This greatly simplifies the code, and hopefully makes it more clear what is happening here. Reviewed by Eric Christopher. There is some concern that we'd like to ensure this doesn't get out of hand, and I plan to benchmark the effects of this change over the next few days along with some further fixes to the inline cost. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152368 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-08Taken into account Duncan's comments for r149481 dated by 2nd Feb 2012:Stepan Dyatkovskiy
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. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152297 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-08Rotate two of the functions used to count bonuses for the inline costChandler Carruth
analysis to be methods on the cost analysis's function info object instead of the code metrics object. These really are just users of the code metrics, they're building the information for the function's analysis. This is the first step of growing the amount of information we collect about a function in order to cope with pair-wise simplifications due to allocas. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152283 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-07No functionality change. Type::isSized() can be expensive, so avoid calling itNick Lewycky
until after other inexpensive tests. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152195 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-05A few more cases of missing masking in ComputeMaskedBits; found by inspection.Eli Friedman
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152070 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-05Make sure we don't return bits outside the mask in ComputeMaskedBits. PR12189.Eli Friedman
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152066 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-02LVI: Recognize the form instcombine canonicalizes range checks into when ↵Benjamin Kramer
forming constant ranges. This could probably be made a lot smarter, but this is a common case and doesn't require LVI to scan a lot of code. With this change CVP can optimize away the "shift == 0" case in Hashing.h that only gets hit when "shift" is in a range not containing 0. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@151919 91177308-0d34-0410-b5e6-96231b3b80d8
2012-02-27Duncan pointed out that if the alignment isn't explicitly specified, it ↵Eli Friedman
defaults to the ABI alignment. Given that, make this code a bit more aggressive in such cases. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@151584 91177308-0d34-0410-b5e6-96231b3b80d8
2012-02-27Teach BasicAA about the LLVM IR rules that allow reading past the end of an ↵Eli Friedman
object given sufficient alignment. Fixes PR12098. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@151553 91177308-0d34-0410-b5e6-96231b3b80d8
2012-02-27Fix this assert. IP can point to an instruction with strange dominanceRafael Espindola
properties (invoke). Just assert that the instruction we return dominates the insertion point. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@151511 91177308-0d34-0410-b5e6-96231b3b80d8
2012-02-26Don't call dominates on unreachable instructions. Should fix the dragoneggRafael Espindola
build. Testcase is still reducing. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@151474 91177308-0d34-0410-b5e6-96231b3b80d8
2012-02-26And update the comment...Rafael Espindola
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@151472 91177308-0d34-0410-b5e6-96231b3b80d8