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2012-11-01Revert the majority of the next patch in the address space series:Chandler Carruth
r165941: Resubmit the changes to llvm core to update the functions to support different pointer sizes on a per address space basis. Despite this commit log, this change primarily changed stuff outside of VMCore, and those changes do not carry any tests for correctness (or even plausibility), and we have consistently found questionable or flat out incorrect cases in these changes. Most of them are probably correct, but we need to devise a system that makes it more clear when we have handled the address space concerns correctly, and ideally each pass that gets updated would receive an accompanying test case that exercises that pass specificaly w.r.t. alternate address spaces. However, from this commit, I have retained the new C API entry points. Those were an orthogonal change that probably should have been split apart, but they seem entirely good. In several places the changes were very obvious cleanups with no actual multiple address space code added; these I have not reverted when I spotted them. In a few other places there were merge conflicts due to a cleaner solution being implemented later, often not using address spaces at all. In those cases, I've preserved the new code which isn't address space dependent. This is part of my ongoing effort to clean out the partial address space code which carries high risk and low test coverage, and not likely to be finished before the 3.2 release looms closer. Duncan and I would both like to see the above issues addressed before we return to these changes. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167222 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-26Fix a crash in SimpliftDemandedBits of vectors of pointers.Nadav Rotem
PR14183. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166785 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-25Revert 166726 because it may have broken a number of SPEC tests. PR14183.Nadav Rotem
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166739 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-25Fix a crash in ValueTracking. Add support for vectors of pointers.Nadav Rotem
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166726 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-15Resubmit the changes to llvm core to update the functions to support ↵Micah Villmow
different pointer sizes on a per address space basis. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165941 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-11Revert 165732 for further review.Micah Villmow
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165747 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-11Add in the first iteration of support for llvm/clang/lldb to allow variable ↵Micah Villmow
per address space pointer sizes to be optimized correctly. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165726 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-08Move TargetData to DataLayout.Micah Villmow
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165402 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-04The alignment of an sret parameter is known: it must be at least theDuncan Sands
alignment of the return type. Teach the optimizers this. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165226 91177308-0d34-0410-b5e6-96231b3b80d8
2012-09-27Revert 'Fix a typo 'iff' => 'if''. iff is an abreviation of if and only if. ↵Sylvestre Ledru
See: http://en.wikipedia.org/wiki/If_and_only_if Commit 164767 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164768 91177308-0d34-0410-b5e6-96231b3b80d8
2012-09-27Fix a typo 'iff' => 'if'Sylvestre Ledru
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164767 91177308-0d34-0410-b5e6-96231b3b80d8
2012-08-24Fix integer undefined behavior due to signed left shift overflow in LLVM.Richard Smith
Reviewed offline by chandlerc. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@162623 91177308-0d34-0410-b5e6-96231b3b80d8
2012-07-03PHINode::hasConstantValue(): return undef if the PHI is fully recursive.Nuno Lopes
Thanks Duncan for the idea git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@159687 91177308-0d34-0410-b5e6-96231b3b80d8
2012-05-10Teach DeadStoreElimination to eliminate exit-block stores with phi addresses.Dan Gohman
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@156558 91177308-0d34-0410-b5e6-96231b3b80d8
2012-04-30Just mark the sign bit as known zero, rather than any other irrelevant bitsDuncan Sands
known zero in the LHS. Fixes PR12541. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@155818 91177308-0d34-0410-b5e6-96231b3b80d8
2012-04-07Fix ValueTracking to conclude that debug intrinsics are safe toChandler Carruth
speculate. Without this, loop rotate (among many other places) would suddenly stop working in the presence of debug info. I found this looking at loop rotate, and have augmented its tests with a reduction out of a very hot loop in yacr2 where failing to do this rotation costs sometimes more than 10% in runtime performance, perturbing numerous downstream optimizations. This should have no impact on performance without debug info, but the change in performance when debug info is enabled can be extreme. As a consequence (and this how I got to this yak) any profiling of performance problems should be treated with deep suspicion -- they may have been wildly innacurate of debug info was enabled for profiling. =/ Just a heads up. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@154263 91177308-0d34-0410-b5e6-96231b3b80d8
2012-04-04Always compute all the bits in ComputeMaskedBits.Rafael Espindola
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. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@154011 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-31Teach CodeGen's version of computeMaskedBits to understand the range metadata.Rafael Espindola
This is the CodeGen equivalent of r153747. I tested that there is not noticeable performance difference with any combination of -O0/-O2 /-g when compiling gcc as a single compilation unit. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153817 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-30Add computeMaskedBitsLoad back, as it was the change to instsimplify thatRafael Espindola
caused the slowdown last time. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153747 91177308-0d34-0410-b5e6-96231b3b80d8
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
2012-03-26Revert 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
2012-03-18Factor 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
2012-03-09Factor 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
2012-03-07No 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
2012-02-06Remove some dead code and tidy things up now that vectors use ConstantDataVectorChris Lattner
instead of always using ConstantVector. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@149912 91177308-0d34-0410-b5e6-96231b3b80d8
2012-02-06[unwind removal] Remove all of the code for the dead 'unwind' instruction. ThereBill Wendling
were no 'unwind' instructions being generated before this, so this is in effect a no-op. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@149906 91177308-0d34-0410-b5e6-96231b3b80d8
2012-02-05reapply the patches reverted in r149470 that reenable ConstantDataArray,Chris Lattner
but with a critical fix to the SelectionDAG code that optimizes copies from strings into immediate stores: the previous code was stopping reading string data at the first nul. Address this by adding a new argument to llvm::getConstantStringInfo, preserving the behavior before the patch. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@149800 91177308-0d34-0410-b5e6-96231b3b80d8
2012-02-01Revert Chris' commits up to r149348 that started causing VMCoreTests unit ↵Argyrios Kyrtzidis
test to fail. These are: r149348 r149351 r149352 r149354 r149356 r149357 r149361 r149362 r149364 r149365 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@149470 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-31remove the last vestiges of llvm::GetConstantStringInfo, in CodeGen.Chris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@149356 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-31Change ConstantArray::get to form a ConstantDataArray when possible,Chris Lattner
kicking in the big win of ConstantDataArray. As part of this, change the implementation of GetConstantStringInfo in ValueTracking to work with ConstantDataArray (and not ConstantArray) making it dramatically, amazingly, more efficient in the process and renaming it to getConstantStringInfo. This keeps around a GetConstantStringInfo entrypoint that (grossly) forwards to getConstantStringInfo and constructs the std::string required, but existing clients should move over to getConstantStringInfo instead. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@149351 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-26progress making the world safe to ConstantDataVector. WhileChris Lattner
we're at it, allow PatternMatch's "neg" pattern to match integer vector negations, and enhance ComputeNumSigned bits to handle shl of vectors. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@149082 91177308-0d34-0410-b5e6-96231b3b80d8
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
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