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2012-01-25use Constant::getAggregateElement to simplify a bunch of code.Chris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@148934 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-25Use the right method to get the # elements in a CDS.Chris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@148897 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-24teach valuetracking about ConstantDataSequentialChris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@148790 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-04Generalize isSafeToSpeculativelyExecute to work on arbitraryDan Gohman
Values, rather than just Instructions, since it's interesting for ConstantExprs too. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147560 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-01PatternMatch: Introduce a matcher for instructions with the "exact" bit. Use ↵Benjamin Kramer
it to simplify a few matchers. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147403 91177308-0d34-0410-b5e6-96231b3b80d8
2011-12-24ComputeMaskedBits: Make knownzero computation more aggressive for ctlz with ↵Benjamin Kramer
undef zero. unsigned foo(unsigned x) { return 31 - __builtin_clz(x); } now compiles into a single "bsrl" instruction on x86. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147255 91177308-0d34-0410-b5e6-96231b3b80d8
2011-12-21Make some intrinsics safe to speculatively execute.Nick Lewycky
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147036 91177308-0d34-0410-b5e6-96231b3b80d8
2011-12-14Move Instruction::isSafeToSpeculativelyExecute out of VMCore andDan Gohman
into Analysis as a standalone function, since there's no need for it to be in VMCore. Also, update it to use isKnownNonZero and other goodies available in Analysis, making it more precise, enabling more aggressive optimization. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@146610 91177308-0d34-0410-b5e6-96231b3b80d8
2011-12-06Probably not a good idea to convert a single vector load into a memcpy. WeChad Rosier
don't do this now, but add a test case to prevent this from happening in the future. Additional test for rdar://9892684 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@145879 91177308-0d34-0410-b5e6-96231b3b80d8
2011-12-05Add support for vectors of pointers.Nadav Rotem
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@145801 91177308-0d34-0410-b5e6-96231b3b80d8
2011-11-29Fix a theoretical problem (not seen in the wild): if different instances of aDuncan Sands
weak variable are compiled by different compilers, such as GCC and LLVM, while LLVM may increase the alignment to the preferred alignment there is no reason to think that GCC will use anything more than the ABI alignment. Since it is the GCC version that might end up in the final program (as the linkage is weak), it is wrong to increase the alignment of loads from the global up to the preferred alignment as the alignment might only be the ABI alignment. Increasing alignment up to the ABI alignment might be OK, but I'm not totally convinced that it is. It seems better to just leave the alignment of weak globals alone. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@145413 91177308-0d34-0410-b5e6-96231b3b80d8
2011-11-28Make SelectionDAG::InferPtrAlignment use llvm::ComputeMaskedBits instead of ↵Eli Friedman
duplicating the logic for globals. Make llvm::ComputeMaskedBits handle GlobalVariables slightly more aggressively, to match what InferPtrAlignment knew how to do. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@145304 91177308-0d34-0410-b5e6-96231b3b80d8
2011-11-23Fix a crash in which a multiplication was being reported as being both negativeDuncan Sands
and positive: positive, because it could be directly computed to be positive; negative, because the nsw flags means it is either negative or undefined (the multiplication always overflowed). git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@145104 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-28A shift of a power of two is a power of two or zero.Duncan Sands
For completeness - not spotted in the wild. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@143211 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-27Reapply commit 143028 with a fix: the problem was casting a ConstantExpr MulDuncan Sands
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. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@143125 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-27Revert Duncan's r143028 expression folding which appears to be the culpritBob Wilson
behind a compile failure on 483.xalancbmk. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@143102 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-26The maximum power of 2 dividing a power of 2 is itself. This occursDuncan Sands
in 403.gcc and was spotted by my super-optimizer. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@143054 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-26My super-optimizer noticed that we weren't folding this expression toDuncan Sands
true: (x *nsw x) sgt 0, where x = (y | 1). This occurs in 464.h264ref. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@143028 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-20"@string = constant i8 0" is a value i8* string of length zero. Analyze thatNick Lewycky
correctly in GetStringLength, fixing PR11181! git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142558 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-18Migrate LLVM and Clang to use the new makeArrayRef(...) functions where ↵Frits van Bommel
previously explicit non-default constructors were used. Mostly mechanical with some manual reformatting. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@135390 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-18land David Blaikie's patch to de-constify Type, with a few tweaks.Chris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@135375 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-13Convert InsertValueInst and ExtractValueInst APIs to use ArrayRef.Jay Foad
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@135040 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-27Move onlyUsedByLifetimeMarkers to ValueTracking so that it can be used by otherNick Lewycky
passes as well. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@133904 91177308-0d34-0410-b5e6-96231b3b80d8
2011-05-26Renamed llvm.x86.sse42.crc32 intrinsics; crc64 doesn't exist. Chad Rosier
crc32.[8|16|32] have been renamed to .crc32.32.[8|16|32] and crc64.[8|16|32] have been renamed to .crc32.64.[8|64]. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@132163 91177308-0d34-0410-b5e6-96231b3b80d8
2011-05-23Teach valuetracking that byval arguments with a specified alignment areChris Lattner
aligned. Teach memcpyopt to not give up all hope when confonted with an underaligned memcpy feeding an overaligned byval. If the *source* of the memcpy can be determined to be adequeately aligned, or if it can be forced to be, we can eliminate the memcpy. This addresses PR9794. We now compile the example into: define i32 @f(%struct.p* nocapture byval align 8 %q) nounwind ssp { entry: %call = call i32 @g(%struct.p* byval align 8 %q) nounwind ret i32 %call } in both x86-64 and x86-32 mode. We still don't get a tailcall though, because tailcalls apparently can't handle byval. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@131884 91177308-0d34-0410-b5e6-96231b3b80d8
2011-05-22Teach ValueTracking about x86 crc32 intrinsics.Evan Cheng
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@131861 91177308-0d34-0410-b5e6-96231b3b80d8
2011-04-15Fix a ton of comment typos found by codespell. Patch byChris Lattner
Luis Felipe Strano Moraes! git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@129558 91177308-0d34-0410-b5e6-96231b3b80d8
2011-04-02Don't assume something which might be a constant expression is an instruction.Eli Friedman
Based on PR9429, but no testcase because I can't figure out how to trigger it anymore given other changes to the relevant code. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128781 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-21Fix INT_MIN gotcha pointed out by Eli Friedman.Nick Lewycky
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128028 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-12Teach ComputeMaskedBits about sub nsw.Benjamin Kramer
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127548 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-11ComputeMaskedBits: sub falls through to add, and sub doesn't have the same ↵Benjamin Kramer
overflow semantics as add. Should fix the selfhost failures that started with r127463. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127465 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-11Teach ComputeMaskedBits about nsw on add. I don't think there's anything we canNick Lewycky
do with nuw here, but sub and mul should be given similar treatment. Fixes PR9343 #15! git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127463 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-08Fix PR9331. Simplified version of a patch by Jakub Staszak.Duncan Sands
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127243 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-07Add more analysis of the sign bit of an srem instruction. If the LHS is negativeNick Lewycky
then the result could go either way. If it's provably positive then so is the srem. Fixes PR9343 #7! git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127146 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-28Fix comment.Nick Lewycky
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126645 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-28srem doesn't actually have the same resulting sign as its numerator, you couldNick Lewycky
also have a zero when numerator = denominator. Reverts parts of r126635 and r126637. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126644 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-28Teach value tracking to make use of flags in more situations.Nick Lewycky
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126642 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-28Teach ValueTracking to look at the dividend when determining the sign bit of anNick Lewycky
srem instruction. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126637 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-19Stores of null pointers should turn into memset, we weren't recognizingChris Lattner
them as splat values. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126041 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-10Tolerate degenerate phi nodes that can occur in the middle of optimizationNick Lewycky
passes. Fixes PR9112. Patch by Jakub Staszak! git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125319 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-01Add a m_SignBit pattern for convenience.Duncan Sands
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124656 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-29Fix typo: should have been testing that X was odd, not V.Duncan Sands
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124533 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-26APInt has a method for determining whether a number is a power of 2Duncan Sands
which is more efficient than countPopulation - use it. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124283 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-25In which I discover that zero+zero is zero, d'oh!Duncan Sands
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124188 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-25See if this fixes llvm-gcc bootstrap.Duncan Sands
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124184 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-25According to my auto-simplifier the most common missed simplifications inDuncan Sands
optimized code are: (non-negative number)+(power-of-two) != 0 -> true and (x | 1) != 0 -> true Instcombine knows about the second one of course, but only does it if X|1 has only one use. These fire thousands of times in the testsuite. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124183 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-24Give GetUnderlyingObject a TargetData, to keep it in syncDan Gohman
with BasicAA's DecomposeGEPExpression, which recently began using a TargetData. This fixes PR8968, though the testcase is awkward to reduce. Also, update several off GetUnderlyingObject's users which happen to have a TargetData handy to pass it in. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124134 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-04fix an off-by-one bug that caused a crash analyzingChris Lattner
ashr's with huge shift amounts, PR8896 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122814 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-26move isBytewiseValue out to ValueTracking.h/cppChris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122565 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-17Add vector versions of some existing scalar transforms to aid codegen in ↵Nate Begeman
matching psign & pblend operations to the IR produced by clang/gcc for their C idioms. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122105 91177308-0d34-0410-b5e6-96231b3b80d8
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