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* [ConstantRange] Add sdiv() supportNikita Popov2019-06-031-0/+87
| | | | | | | | | | | | | | | | | | | | | | | | | The implementation is conceptually simple: We separate the LHS and RHS into positive and negative components and then also compute the positive and negative components of the result, taking into account that e.g. only pos/pos and neg/neg will give a positive result. However, there's one significant complication: SignedMin / -1 is UB for sdiv, and we can't just ignore it, because the APInt result of SignedMin would break the sign segregation. Instead we drop SignedMin or -1 from the corresponding ranges, taking into account some edge cases with wrapped ranges. Because of the sign segregation, the implementation ends up being nearly fully precise even for wrapped ranges (the remaining imprecision is due to ranges that are both signed and unsigned wrapping and are divided by a trivial divisor like 1). This means that the testing cannot just check the signed envelope as we usually do. Instead we collect all possible results in a bitvector and construct a better sign wrapped range (than the full envelope). Differential Revision: https://reviews.llvm.org/D61238 llvm-svn: 362430
* [ValueTracking][ConstantRange] Distinguish low/high always overflowNikita Popov2019-05-281-9/+9
| | | | | | | | | | | | In order to fold an always overflowing signed saturating add/sub, we need to know in which direction the always overflow occurs. This patch splits up AlwaysOverflows into AlwaysOverflowsLow and AlwaysOverflowsHigh to pass through this information (but it is not used yet). Differential Revision: https://reviews.llvm.org/D62463 llvm-svn: 361858
* [CVP] Remove unnecessary checks for empty GNWR; NFCNikita Popov2019-05-251-2/+1
| | | | | | | | | | The guaranteed no-wrap region is never empty, it always contains at least zero, so these optimizations don't ever apply. To make this more obviously true, replace the conversative return in makeGNWR with an assertion. llvm-svn: 361698
* [ConstantRange] Simplify makeGNWR implementation; NFCNikita Popov2019-05-071-103/+67
| | | | | | | | Compute results in more direct ways, avoid subset intersect operations. Extract the core code for computing mul nowrap ranges into separate static functions, so they can be reused. llvm-svn: 360189
* [ConstantRange] Add srem() supportNikita Popov2019-05-061-0/+44
| | | | | | | | | | | | | | | Add support for srem() to ConstantRange so we can use it in LVI. For srem the sign of the result matches the sign of the LHS. For the RHS only the absolute value is important. Apart from that the logic is like urem. Just like for urem this is only an approximate implementation. The tests check a few specific cases and run an exhaustive test for conservative correctness (but not exactness). Differential Revision: https://reviews.llvm.org/D61207 llvm-svn: 360055
* [ConstantRange] Add makeExactNoWrapRegion()Nikita Popov2019-04-281-4/+10
| | | | | | | | | | | | | | | | | | | | | | | I got confused on the terminology, and the change in D60598 was not correct. I was thinking of "exact" in terms of the result being non-approximate. However, the relevant distinction here is whether the result is * Largest range such that: Forall Y in Other: Forall X in Result: X BinOp Y does not wrap. (makeGuaranteedNoWrapRegion) * Smallest range such that: Forall Y in Other: Forall X not in Result: X BinOp Y wraps. (A hypothetical makeAllowedNoWrapRegion) * Both. (makeExactNoWrapRegion) I'm adding a separate makeExactNoWrapRegion method accepting a single APInt (same as makeExactICmpRegion) and using it in the places where the guarantee is relevant. Differential Revision: https://reviews.llvm.org/D60960 llvm-svn: 359402
* [ConstantRange] Add abs() supportNikita Popov2019-04-261-0/+31
| | | | | | | | | | | | | | Add support for abs() to ConstantRange. This will allow to handle SPF_ABS select flavor in LVI and will also come in handy as a primitive for the srem implementation. The implementation is slightly tricky, because a) abs of signed min is signed min and b) sign-wrapped ranges may have an abs() that is smaller than a full range, so we need to explicitly handle them. Differential Revision: https://reviews.llvm.org/D61084 llvm-svn: 359321
* [ConstantRange] [a, b) udiv a full range is [0, umax(b)).Florian Hahn2019-04-251-2/+0
| | | | | | | | | | Reviewers: nikic, spatel, efriedma Reviewed By: nikic Differential Revision: https://reviews.llvm.org/D60536 llvm-svn: 359180
* [ConstantRange] Add urem supportNikita Popov2019-04-231-0/+15
| | | | | | | | | | | | | Add urem support to ConstantRange, so we can handle in in LVI. This is an approximate implementation that tries to capture the most useful conditions: If the LHS is always strictly smaller than the RHS, then the urem is a no-op and the result is the same as the LHS range. Otherwise the lower bound is zero and the upper bound is min(LHSMax, RHSMax - 1). Differential Revision: https://reviews.llvm.org/D60952 llvm-svn: 359019
* Revert "[ConstantRange] Rename make{Guaranteed -> Exact}NoWrapRegion() NFC"Nikita Popov2019-04-221-7/+8
| | | | | | | | | | This reverts commit 7bf4d7c07f2fac862ef34c82ad0fef6513452445. After thinking about this more, this isn't right, the range is not exact in the same sense as makeExactICmpRegion(). This needs a separate function. llvm-svn: 358876
* [ConstantRange] Rename make{Guaranteed -> Exact}NoWrapRegion() NFCNikita Popov2019-04-221-8/+7
| | | | | | | | Following D60632 makeGuaranteedNoWrapRegion() always returns an exact nowrap region. Rename the function accordingly. This is in line with the naming of makeExactICmpRegion(). llvm-svn: 358875
* [ConstantRange] Add saturating add/sub methodsNikita Popov2019-04-211-0/+36
| | | | | | | | | | | | | | | | Add support for uadd_sat and friends to ConstantRange, so we can handle uadd.sat and friends in LVI. The implementation is forwarding to the corresponding APInt methods with appropriate bounds. One thing worth pointing out here is that the handling of wrapping ranges is not maximally accurate. A simple example is that adding 0 to a wrapped range will return a full range, rather than the original wrapped range. The tests also only check that the non-wrapping envelope is correct and minimal. Differential Revision: https://reviews.llvm.org/D60946 llvm-svn: 358855
* [ConstantRange] Add getNonEmpty() constructorNikita Popov2019-04-211-57/+17
| | | | | | | | | | | | | | ConstantRanges have an annoying special case: If upper and lower are the same, it can be either an empty or a full set. When constructing constant ranges nearly always a full set is intended, but this still requires an explicit check in many places. This revision adds a getNonEmpty() constructor that disambiguates this case: If upper and lower are the same, a full set is created. Differential Revision: https://reviews.llvm.org/D60947 llvm-svn: 358854
* [ConstantRange] Delete unused getSetSizeFangrui Song2019-04-141-8/+0
| | | | | | getSetSize returns an APInt that is 1 bit wider. The APInt is typically 65-bit and requires memory allocation. isSizeStrictlySmallerThan and isSizeLargerThan are preferred. The last use of this helper method was removed by rL302385. llvm-svn: 358347
* [ConstantRange] Disallow NUW | NSW in makeGuaranteedNoWrapRegion()Nikita Popov2019-04-131-18/+14
| | | | | | | | | | | | | | | As motivated in D60598, this drops support for specifying both NUW and NSW in makeGuaranteedNoWrapRegion(). None of the users of this function currently make use of this. When both NUW and NSW are specified, the exact nowrap region has two disjoint parts and makeGNWR() returns one of them. This result doesn't seem to be useful for anything, but makes the semantics of the function fuzzier. Differential Revision: https://reviews.llvm.org/D60632 llvm-svn: 358340
* [ConstantRange] Clarify makeGuaranteedNoWrapRegion() guarantees; NFCNikita Popov2019-04-121-2/+1
| | | | | | | | | | | | | | | | | | | | | makeGuaranteedNoWrapRegion() is actually makeExactNoWrapRegion() as long as only one of NUW or NSW is specified. This is not obvious from the current documentation, and some code seems to think that it is only exact for single-element ranges. Clarify docs and add tests to be more confident this really holds. There are currently no users of makeGuaranteedNoWrapRegion() that pass both NUW and NSW. I think it would be best to drop support for this entirely and then rename the function to makeExactNoWrapRegion(). Knowing that the no-wrap region is exact is useful, because we can backwards-constrain values. What I have in mind in particular is that LVI should be able to constrain values on edges where the with.overflow overflow flag is false. Differential Revision: https://reviews.llvm.org/D60598 llvm-svn: 358305
* [ConstantRange] Add unsignedMulMayOverflow()Nikita Popov2019-04-111-0/+20
| | | | | | | | | | Same as the other ConstantRange overflow checking methods, but for unsigned mul. In this case there is no cheap overflow criterion, so using umul_ov for the implementation. Differential Revision: https://reviews.llvm.org/D60574 llvm-svn: 358228
* [ConstantRange] Delete redundnt {z,s}extOrSelf for multiplicationFangrui Song2019-04-081-7/+0
| | | | | | | These calls are redundant because the quotients have the same BitWidth as MinValue/MaxValue. llvm-svn: 357886
* [ConstantRange] Add signed/unsigned unionWith()Nikita Popov2019-04-071-18/+20
| | | | | | | | | | | | | | | | This extends D59959 to unionWith(), allowing to specify that a non-wrapping unsigned/signed range is preferred. This is somewhat less useful than the intersect case, because union operations are rarer. An example use would the the phi union computed in SCEV. The implementation is mostly a straightforward use of getPreferredRange(), but I also had to adjust some <=/< checks to make sure that no ranges with lower==upper get constructed before they're passed to getPreferredRange(), as these have additional constraints. Differential Revision: https://reviews.llvm.org/D60377 llvm-svn: 357876
* [ConstantRange] Add unsigned and signed intersection typesNikita Popov2019-04-071-13/+65
| | | | | | | | | | | | | | | | | | | | | | | | The intersection of two ConstantRanges may consist of two disjoint ranges. As we can only return one range as the result, we need to return one of the two possible ranges that cover both. Currently the result is picked based on set size. However, this is not always optimal: If we're in an unsigned context, we'd prefer to get a large unsigned range over a small signed range -- the latter effectively becomes a full set in the unsigned domain. This revision adds a PreferredRangeType, which can be either Smallest, Unsigned or Signed. Smallest is the current behavior and Unsigned and Signed are new variants that prefer not to wrap the unsigned/signed domain. The new type isn't used anywhere yet (but SCEV will be a good first user, see D60035). I've also added some comments to illustrate the various cases in intersectWith(), which should hopefully make it more obvious what is going on. Differential Revision: https://reviews.llvm.org/D59959 llvm-svn: 357873
* [ConstantRange] Add isAllNegative() and isAllNonNegative() methodsNikita Popov2019-04-071-0/+15
| | | | | | | | | | | | | Add isAllNegative() and isAllNonNegative() methods to ConstantRange, which determine whether all values in the constant range are negative/non-negative. This is useful for replacing KnownBits isNegative() and isNonNegative() calls when changing code to use constant ranges. Differential Revision: https://reviews.llvm.org/D60264 llvm-svn: 357871
* [ConstantRange] Shl considers full-set shifting to last bit position.Marcello Maggioni2019-04-071-1/+5
| | | | | | | | | | | | | if we do SHL of two 16-bit ranges like [0, 30000) with [1,2) we get "full-set" instead of what I would have expected [0, 60000) which is still in the 16-bit unsigned range. This patch changes the SHL algorithm to allow getting a usable range even in this case. Differential Revision: https://reviews.llvm.org/D57983 llvm-svn: 357854
* [ConstantRange] Add isWrappedSet() and isUpperSignWrapped()Nikita Popov2019-03-271-3/+11
| | | | | | | | | | | | | | | Split off from D59749. This adds isWrappedSet() and isUpperSignWrapped() set with the same behavior as isSignWrappedSet() and isUpperWrapped() for the respectively other domain. The methods isWrappedSet() and isSignWrappedSet() will not consider ranges of the form [X, Max] == [X, 0) and [X, SignedMax] == [X, SignedMin) to be wrapping, while isUpperWrapped() and isUpperSignWrapped() will. Also replace the checks in getUnsignedMin() and friends with method calls that implement the same logic. llvm-svn: 357112
* [ConstantRange] Rename isWrappedSet() to isUpperWrapped()Nikita Popov2019-03-271-16/+16
| | | | | | | | | | | | | | Split out from D59749. The current implementation of isWrappedSet() doesn't do what it says on the tin, and treats ranges like [X, Max] as wrapping, because they are represented as [X, 0) when using half-inclusive ranges. This also makes it inconsistent with the semantics of isSignWrappedSet(). This patch renames isWrappedSet() to isUpperWrapped(), in preparation for the introduction of a new isWrappedSet() method with corrected behavior. llvm-svn: 357107
* [ConstantRange] Exclude full set from isSignWrappedSet()Nikita Popov2019-03-261-2/+1
| | | | | | | | | | | | | | | Split off from D59749. This uses a simpler and more efficient implementation of isSignWrappedSet(), and considers full sets as non-wrapped, to be consistent with isWrappedSet(). Otherwise the behavior is unchanged. There are currently only two users of this function and both already check for isFullSet() || isSignWrappedSet(), so this is not going to cause a change in overall behavior. Differential Revision: https://reviews.llvm.org/D59848 llvm-svn: 357039
* [ConstantRange] Add getFull() + getEmpty() named constructors; NFCNikita Popov2019-03-241-64/+64
| | | | | | | | | | | | | | | | This adds ConstantRange::getFull(BitWidth) and ConstantRange::getEmpty(BitWidth) named constructors as more readable alternatives to the current ConstantRange(BitWidth, /* full */ false) and similar. Additionally private getFull() and getEmpty() member functions are added which return a full/empty range with the same bit width -- these are commonly needed inside ConstantRange.cpp. The IsFullSet argument in the ConstantRange(BitWidth, IsFullSet) constructor is now mandatory for the few usages that still make use of it. Differential Revision: https://reviews.llvm.org/D59716 llvm-svn: 356852
* [ConstantRange] Add assertion for KnownBits validity; NFCNikita Popov2019-03-171-0/+2
| | | | | | Following the suggestion in D59475. llvm-svn: 356346
* [ConstantRange] Add fromKnownBits() methodNikita Popov2019-03-171-0/+19
| | | | | | | | | | | | | | Following the suggestion in D59450, I'm moving the code for constructing a ConstantRange from KnownBits out of ValueTracking, which also allows us to test this code independently. I'm adding this method to ConstantRange rather than KnownBits (which would have been a bit nicer API wise) to avoid creating a dependency from Support to IR, where ConstantRange lives. Differential Revision: https://reviews.llvm.org/D59475 llvm-svn: 356339
* [ConstantRange] Add overflow check helpersNikita Popov2019-03-151-0/+92
| | | | | | | | | | | | | | | | | | | | Add functions to ConstantRange that determine whether the unsigned/signed addition/subtraction of two ConstantRanges may/always/never overflows. This will allow checking overflow conditions based on known constant ranges in addition to known bits. I'm implementing these methods on ConstantRange to allow them to be unit tested independently of any ValueTracking machinery. The tests include exhaustive testing on 4-bit ranges, to make sure the result is both conservatively correct and maximally precise. The OverflowResult enum is redeclared on ConstantRange, because I wanted to avoid a dependency in either direction between ValueTracking.h and ConstantRange.h. Differential Revision: https://reviews.llvm.org/D59193 llvm-svn: 356276
* Update the file headers across all of the LLVM projects in the monorepoChandler Carruth2019-01-191-4/+3
| | | | | | | | | | | | | | | | | to reflect the new license. We understand that people may be surprised that we're moving the header entirely to discuss the new license. We checked this carefully with the Foundation's lawyer and we believe this is the correct approach. Essentially, all code in the project is now made available by the LLVM project under our new license, so you will see that the license headers include that license only. Some of our contributors have contributed code under our old license, and accordingly, we have retained a copy of our old license notice in the top-level files in each project and repository. llvm-svn: 351636
* [IR] Strip trailing whitespace. NFCBjorn Pettersson2018-07-031-4/+4
| | | | llvm-svn: 336194
* [ConstantRange] Add support of mul in makeGuaranteedNoWrapRegion.Tim Shen2018-06-261-0/+58
| | | | | | | | | | | | Summary: This is trying to add support for r334428. Reviewers: sanjoy Subscribers: jlebar, hiraditya, bixia, llvm-commits Differential Revision: https://reviews.llvm.org/D48399 llvm-svn: 335646
* [IR] Use Instruction::isBinaryOp helper instead of raw enum range tests. NFCI.Simon Pilgrim2018-06-221-4/+2
| | | | llvm-svn: 335335
* IWYU for llvm-config.h in llvm, additions.Nico Weber2018-04-301-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | See r331124 for how I made a list of files missing the include. I then ran this Python script: for f in open('filelist.txt'): f = f.strip() fl = open(f).readlines() found = False for i in xrange(len(fl)): p = '#include "llvm/' if not fl[i].startswith(p): continue if fl[i][len(p):] > 'Config': fl.insert(i, '#include "llvm/Config/llvm-config.h"\n') found = True break if not found: print 'not found', f else: open(f, 'w').write(''.join(fl)) and then looked through everything with `svn diff | diffstat -l | xargs -n 1000 gvim -p` and tried to fix include ordering and whatnot. No intended behavior change. llvm-svn: 331184
* [ConstantRange] Support for ashr in ConstantRange computationMax Kazantsev2017-12-181-0/+56
| | | | | | | | | | | Extend the ConstantRange implementation to compute the range of possible values resulting from an arithmetic right shift operation. There will be a follow up patch to leverage this constant range infrastructure in LazyValueInfo. Patch by Surya Kumari Jangala! Differential Revision: https://reviews.llvm.org/D40881 llvm-svn: 320976
* [ConstantRange] Support subtraction in makeGuaranteedNoWrapRegion.Joel Galenson2017-12-051-28/+52
| | | | | | | | Previously ConstantRange::makeGuaranteedNoWrapRegion only handled addition. This adds support for subtraction. Differential Revision: https://reviews.llvm.org/D40036 llvm-svn: 319806
* Reverting r315590; it did not include changes for llvm-tblgen, which is ↵Aaron Ballman2017-10-151-1/+1
| | | | | | | | causing link errors for several people. Error LNK2019 unresolved external symbol "public: void __cdecl `anonymous namespace'::MatchableInfo::dump(void)const " (?dump@MatchableInfo@?A0xf4f1c304@@QEBAXXZ) referenced in function "public: void __cdecl `anonymous namespace'::AsmMatcherEmitter::run(class llvm::raw_ostream &)" (?run@AsmMatcherEmitter@?A0xf4f1c304@@QEAAXAEAVraw_ostream@llvm@@@Z) llvm-tblgen D:\llvm\2017\utils\TableGen\AsmMatcherEmitter.obj 1 llvm-svn: 315854
* [dump] Remove NDEBUG from test to enable dump methods [NFC]Don Hinton2017-10-121-1/+1
| | | | | | | | | | | | | | | Summary: Add LLVM_FORCE_ENABLE_DUMP cmake option, and use it along with LLVM_ENABLE_ASSERTIONS to set LLVM_ENABLE_DUMP. Remove NDEBUG and only use LLVM_ENABLE_DUMP to enable dump methods. Move definition of LLVM_ENABLE_DUMP from config.h to llvm-config.h so it'll be picked up by public headers. Differential Revision: https://reviews.llvm.org/D38406 llvm-svn: 315590
* [IR] Fix some Clang-tidy modernize-use-using warnings; other minor fixes (NFC).Eugene Zelenko2017-06-191-2/+11
| | | | llvm-svn: 305755
* [ConstantRange] Implement getSignedMin/Max in a less complicated and faster wayCraig Topper2017-06-161-15/+2
| | | | | | | | | | | | | | Summary: As far as I can tell we should be able to implement these almost the same way we do unsigned, but using signed comparisons and checks for min signed value instead of min unsigned value. Reviewers: pete, davide, sanjoy Reviewed By: davide Subscribers: llvm-commits Differential Revision: https://reviews.llvm.org/D33815 llvm-svn: 305607
* Sort the remaining #include lines in include/... and lib/....Chandler Carruth2017-06-061-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | I did this a long time ago with a janky python script, but now clang-format has built-in support for this. I fed clang-format every line with a #include and let it re-sort things according to the precise LLVM rules for include ordering baked into clang-format these days. I've reverted a number of files where the results of sorting includes isn't healthy. Either places where we have legacy code relying on particular include ordering (where possible, I'll fix these separately) or where we have particular formatting around #include lines that I didn't want to disturb in this patch. This patch is *entirely* mechanical. If you get merge conflicts or anything, just ignore the changes in this patch and run clang-format over your #include lines in the files. Sorry for any noise here, but it is important to keep these things stable. I was seeing an increasing number of patches with irrelevant re-ordering of #include lines because clang-format was used. This patch at least isolates that churn, makes it easy to skip when resolving conflicts, and gets us to a clean baseline (again). llvm-svn: 304787
* [ConstantRange] Remove costly udivrem from ConstantRange::truncateCraig Topper2017-06-051-15/+19
| | | | | | | | | | | | Truncate currently uses a udivrem call which is going to be slow particularly for larger than 64-bit widths. As far as I can tell all we were trying to do was modulo LowerDiv by (MaxValue+1) and make sure whatever value was effectively subtracted from LowerDiv was also subtracted from UpperDiv. This patch recognizes that MaxValue+1 is a power of 2 so we can just use a bitwise AND to accomplish a modulo operation or isolate the upper bits. Differential Revision: https://reviews.llvm.org/D32672 llvm-svn: 304733
* [ConstantRange] Fix the early out in ConstantRange::multiply for positive ↵Craig Topper2017-05-101-1/+2
| | | | | | | | | | numbers to really do what the comment says r271020 added an early out to skip the signed multiply portion of ConstantRange::multiply. The comment says we don't need to do signed multiply if the range is only positive numbers, but the implemented check only ensures that the start of the range is positive. It doesn't look at the end of the range. This patch checks the end of the range instead. Because Upper is one more than the end we have to see if its positive or if its one past the last positive number. llvm-svn: 302717
* [ConstantRange] Rewrite shl to avoid repeated calls to getUnsignedMax and ↵Craig Topper2017-05-091-7/+11
| | | | | | avoid creating the min APInt until we're sure we need it. Use inplace shift operations. llvm-svn: 302510
* [ConstantRange] Combine the two adds max+1 in lshr into a single addition.Craig Topper2017-05-091-4/+4
| | | | llvm-svn: 302509
* [ConstantRange] Use APInt::isNullValue in place of comparing with 0. The ↵Craig Topper2017-05-091-4/+4
| | | | | | compiler should be able to generate slightly better code for the former. NFC llvm-svn: 302508
* [ConstantRange][SimplifyCFG] Add a helper method to allow SimplifyCFG to ↵Craig Topper2017-05-071-0/+11
| | | | | | | | | | determine if a ConstantRange has more than 8 elements without requiring an allocation if the ConstantRange is 64-bits wide. Previously SimplifyCFG used getSetSize which returns an APInt that is 1 bit wider than the ConstantRange's bit width. In the reasonably common case that the ConstantRange is 64-bits wide, this requires returning a 65-bit APInt. APInt's can only store 64-bits without a memory allocation so this is inefficient. The new method takes the 8 as an input and tells if the range contains more than that many elements without requiring any wider math. llvm-svn: 302385
* [ConstantRange] Remove 'Of' from name of ↵Craig Topper2017-05-071-9/+9
| | | | | | ConstantRange::isSizeStrictlySmallerThanOf so that it reads better. NFC llvm-svn: 302383
* [ConstantRange] Fix a couple cases where we were possibly throwing away an ↵Craig Topper2017-04-301-2/+2
| | | | | | | | APInt allocation we could reuse. NFC This uses setAllBits to replace getMaxValue and operator=(uint64_t) instead of constructing an APInt from uint64_t. llvm-svn: 301761
* [ConstantRange] Use APInt::getOneBitSet to shorten some code. NFCCraig Topper2017-04-291-5/+2
| | | | llvm-svn: 301753
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