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* Apply clang-tidy's modernize-loop-convert to most of lib/Transforms.Benjamin Kramer2016-06-261-27/+26
| | | | | | Only minor manual fixes. No functionality change intended. llvm-svn: 273808
* Revert "[SimplifyCFG] Stop inserting calls to llvm.trap for UB"David Majnemer2016-06-251-1/+2
| | | | | | This reverts commit r273778, it seems to break UBSan :/ llvm-svn: 273779
* [SimplifyCFG] Stop inserting calls to llvm.trap for UBDavid Majnemer2016-06-251-2/+1
| | | | | | | | | | | | | | | | | SimplifyCFG had logic to insert calls to llvm.trap for two very particular IR patterns: stores and invokes of undef/null. While InstCombine canonicalizes certain undefined behavior IR patterns to stores of undef, phase ordering means that this cannot be relied upon in general. There are much better tools than llvm.trap: UBSan and ASan. N.B. I could be argued into reverting this change if a clear argument as to why it is important that we synthesize llvm.trap for stores, I'd be hard pressed to see why it'd be useful for invokes... llvm-svn: 273778
* [SCCP] Don't assume all Constants are ConstantIntDavid Majnemer2016-06-231-8/+8
| | | | | | This fixes PR28269. llvm-svn: 273521
* [PM] SCCP should preserve GlobalsAA even if the IR is mutated.Davide Italiano2016-05-291-1/+4
| | | | llvm-svn: 271149
* [SCCP] Prefer class to struct.Davide Italiano2016-05-191-2/+4
| | | | llvm-svn: 270074
* [PM] Port per-function SCCP to the new pass manager.Davide Italiano2016-05-181-44/+52
| | | | llvm-svn: 269937
* [PM/SCCP] Fix pass dependencies.Davide Italiano2016-05-151-1/+4
| | | | | | | | | | | | TargetLibraryInfoWrapperPass is a dependency of SCCP but it's not listed as such. Chandler pointed out this is an easy mistake to make which only surfaces in weird crashes with some flag combinations. This code will go away anyway at some point in the future, but as long as it's (still) exercised, try to make it correct. llvm-svn: 269589
* [SCCP] Use range-based for loops. NFC.Davide Italiano2016-05-141-10/+10
| | | | llvm-svn: 269578
* [SCCP] Resolve shifts beyond the bitwidth to undefDavid Majnemer2016-05-121-0/+16
| | | | | | | | | Shifts beyond the bitwidth are undef but SCCP resolved them to zero. Instead, DTRT and resolve them to undef. This reimplements the transform which caused PR27712. llvm-svn: 269269
* Revert "[SCCP] Partially propagate informations when the input is not fully ↵Davide Italiano2016-05-111-3/+0
| | | | | | | | defined." This reverts commit r269105 as it caused PR27712. llvm-svn: 269252
* [SCCP] Partially propagate informations when the input is not fully defined.Davide Italiano2016-05-101-0/+3
| | | | | | | | | | With this patch: %r1 = lshr i64 -1, 4294967296 -> undef Before this patch: %r1 = lshr i64 -1, 4294967296 -> 0 llvm-svn: 269105
* [PM] Port Interprocedural SCCP to the new pass manager.Davide Italiano2016-05-051-42/+53
| | | | llvm-svn: 268684
* Revert "[SCCP] Throw away dead code. NFC."Davide Italiano2016-05-041-0/+3
| | | | | | This reverts commit r268568, as it broke the bots. llvm-svn: 268570
* [SCCP] Throw away dead code. NFC.Davide Italiano2016-05-041-3/+0
| | | | llvm-svn: 268568
* Re-commit optimization bisect support (r267022) without new pass manager ↵Andrew Kaylor2016-04-221-1/+4
| | | | | | | | | | support. The original commit was reverted because of a buildbot problem with LazyCallGraph::SCC handling (not related to the OptBisect handling). Differential Revision: http://reviews.llvm.org/D19172 llvm-svn: 267231
* Revert "Initial implementation of optimization bisect support."Vedant Kumar2016-04-221-4/+1
| | | | | | | | This reverts commit r267022, due to an ASan failure: http://lab.llvm.org:8080/green/job/clang-stage2-cmake-RgSan_check/1549 llvm-svn: 267115
* Initial implementation of optimization bisect support.Andrew Kaylor2016-04-211-1/+4
| | | | | | | | | | | | This patch implements a optimization bisect feature, which will allow optimizations to be selectively disabled at compile time in order to track down test failures that are caused by incorrect optimizations. The bisection is enabled using a new command line option (-opt-bisect-limit). Individual passes that may be skipped call the OptBisect object (via an LLVMContext) to see if they should be skipped based on the bisect limit. A finer level of control (disabling individual transformations) can be managed through an addition OptBisect method, but this is not yet used. The skip checking in this implementation is based on (and replaces) the skipOptnoneFunction check. Where that check was being called, a new call has been inserted in its place which checks the bisect limit and the optnone attribute. A new function call has been added for module and SCC passes that behaves in a similar way. Differential Revision: http://reviews.llvm.org/D19172 llvm-svn: 267022
* Don't IPO over functions that can be de-refinedSanjoy Das2016-04-081-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: Fixes PR26774. If you're aware of the issue, feel free to skip the "Motivation" section and jump directly to "This patch". Motivation: I define "refinement" as discarding behaviors from a program that the optimizer has license to discard. So transforming: ``` void f(unsigned x) { unsigned t = 5 / x; (void)t; } ``` to ``` void f(unsigned x) { } ``` is refinement, since the behavior went from "if x == 0 then undefined else nothing" to "nothing" (the optimizer has license to discard undefined behavior). Refinement is a fundamental aspect of many mid-level optimizations done by LLVM. For instance, transforming `x == (x + 1)` to `false` also involves refinement since the expression's value went from "if x is `undef` then { `true` or `false` } else { `false` }" to "`false`" (by definition, the optimizer has license to fold `undef` to any non-`undef` value). Unfortunately, refinement implies that the optimizer cannot assume that the implementation of a function it can see has all of the behavior an unoptimized or a differently optimized version of the same function can have. This is a problem for functions with comdat linkage, where a function can be replaced by an unoptimized or a differently optimized version of the same source level function. For instance, FunctionAttrs cannot assume a comdat function is actually `readnone` even if it does not have any loads or stores in it; since there may have been loads and stores in the "original function" that were refined out in the currently visible variant, and at the link step the linker may in fact choose an implementation with a load or a store. As an example, consider a function that does two atomic loads from the same memory location, and writes to memory only if the two values are not equal. The optimizer is allowed to refine this function by first CSE'ing the two loads, and the folding the comparision to always report that the two values are equal. Such a refined variant will look like it is `readonly`. However, the unoptimized version of the function can still write to memory (since the two loads //can// result in different values), and selecting the unoptimized version at link time will retroactively invalidate transforms we may have done under the assumption that the function does not write to memory. Note: this is not just a problem with atomics or with linking differently optimized object files. See PR26774 for more realistic examples that involved neither. This patch: This change introduces a new set of linkage types, predicated as `GlobalValue::mayBeDerefined` that returns true if the linkage type allows a function to be replaced by a differently optimized variant at link time. It then changes a set of IPO passes to bail out if they see such a function. Reviewers: chandlerc, hfinkel, dexonsmith, joker.eph, rnk Subscribers: mcrosier, llvm-commits Differential Revision: http://reviews.llvm.org/D18634 llvm-svn: 265762
* Fix build bot breakageDavid Majnemer2016-01-241-1/+1
| | | | llvm-svn: 258661
* Fix buildbot failuresDavid Majnemer2016-01-241-1/+1
| | | | llvm-svn: 258655
* [SCCP] Remove duplicate codeDavid Majnemer2016-01-241-20/+11
| | | | | | | | | SCCP has code identical to changeToUnreachable's behavior, switch it over to just call changeToUnreachable. No functionality change intended. llvm-svn: 258654
* [InstCombine, SCCP] Consolidate code used to remove instructionsDavid Majnemer2016-01-241-19/+2
| | | | | | | | | InstCombine and SCCP both want to remove dead code in a very particular way but using identical means to do so. Share the code between the two. No functionality change is intended. llvm-svn: 258653
* [opaque pointer types] [NFC] Add an explicit type argument to ↵Eduard Burtescu2016-01-221-1/+1
| | | | | | | | | | | | ConstantFoldLoadFromConstPtr. Reviewers: mjacob, dblaikie Subscribers: llvm-commits Differential Revision: http://reviews.llvm.org/D16418 llvm-svn: 258472
* GlobalValue: use getValueType() instead of getType()->getPointerElementType().Manuel Jacob2016-01-161-1/+1
| | | | | | | | | | | | Reviewers: mjacob Subscribers: jholewinski, arsenm, dsanders, dblaikie Patch by Eduard Burtescu. Differential Revision: http://reviews.llvm.org/D16260 llvm-svn: 257999
* [SCCP] Don't violate the lattice invariantsDavid Majnemer2016-01-071-15/+42
| | | | | | | | | | We marked values which are 'undef' as constant instead of undefined which violates SCCP's invariants. If we can figure out that a computation results in 'undef', leave it in the undefined state. This fixes PR16052. llvm-svn: 257102
* Remove junk accidentally commited with r257087David Majnemer2016-01-071-1/+1
| | | | llvm-svn: 257089
* [SCCP] Can't go from overdefined to constantDavid Majnemer2016-01-071-3/+3
| | | | | | | | The fix for PR23999 made us mark loads of null as producing the constant undef which upsets the lattice. Instead, keep the load as "undefined". This fixes PR26044. llvm-svn: 257087
* [IR] Reformulate LLVM's EH funclet IRDavid Majnemer2015-12-121-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | While we have successfully implemented a funclet-oriented EH scheme on top of LLVM IR, our scheme has some notable deficiencies: - catchendpad and cleanupendpad are necessary in the current design but they are difficult to explain to others, even to seasoned LLVM experts. - catchendpad and cleanupendpad are optimization barriers. They cannot be split and force all potentially throwing call-sites to be invokes. This has a noticable effect on the quality of our code generation. - catchpad, while similar in some aspects to invoke, is fairly awkward. It is unsplittable, starts a funclet, and has control flow to other funclets. - The nesting relationship between funclets is currently a property of control flow edges. Because of this, we are forced to carefully analyze the flow graph to see if there might potentially exist illegal nesting among funclets. While we have logic to clone funclets when they are illegally nested, it would be nicer if we had a representation which forbade them upfront. Let's clean this up a bit by doing the following: - Instead, make catchpad more like cleanuppad and landingpad: no control flow, just a bunch of simple operands; catchpad would be splittable. - Introduce catchswitch, a control flow instruction designed to model the constraints of funclet oriented EH. - Make funclet scoping explicit by having funclet instructions consume the token produced by the funclet which contains them. - Remove catchendpad and cleanupendpad. Their presence can be inferred implicitly using coloring information. N.B. The state numbering code for the CLR has been updated but the veracity of it's output cannot be spoken for. An expert should take a look to make sure the results are reasonable. Reviewers: rnk, JosephTremoulet, andrew.w.kaylor Differential Revision: http://reviews.llvm.org/D15139 llvm-svn: 255422
* [SCCP] More informative message if we don't know how to handle a terminator.Davide Italiano2015-11-251-1/+1
| | | | llvm-svn: 254093
* Scalar: Remove remaining ilist iterator implicit conversionsDuncan P. N. Exon Smith2015-10-131-70/+70
| | | | | | | | | | | | | | | | | | | Remove remaining `ilist_iterator` implicit conversions from LLVMScalarOpts. This change exposed some scary behaviour in lib/Transforms/Scalar/SCCP.cpp around line 1770. This patch changes a call from `Function::begin()` to `&Function::front()`, since the return was immediately being passed into another function that takes a `Function*`. `Function::front()` started to assert, since the function was empty. Note that `Function::end()` does not point at a legal `Function*` -- it points at an `ilist_half_node` -- so the other function was getting garbage before. (I added the missing check for `Function::isDeclaration()`.) Otherwise, no functionality change intended. llvm-svn: 250211
* Add GlobalsAA as preserved to a bunch of transformsJames Molloy2015-09-101-0/+2
| | | | | | GlobalsAA must by definition be preserved in function passes, but the passmanager doesn't know that. Make each pass explicitly preserve GlobalsAA. llvm-svn: 247263
* Convert a bunch of loops to foreach. NFC.Pete Cooper2015-08-061-3/+2
| | | | | | | | After r244074, we now have a successors() method to iterate over all the successors of a TerminatorInst. This commit changes a bunch of eligible loops to use it. llvm-svn: 244260
* Drive-by fixes for LandingPad -> EHPadDavid Majnemer2015-08-041-1/+6
| | | | | | | | This change was done as an audit and is by inspection. The new EH system is still very much a work in progress. NFC for the landingpad case. llvm-svn: 243965
* New EH representation for MSVC compatibilityDavid Majnemer2015-07-311-5/+5
| | | | | | | | | | This introduces new instructions neccessary to implement MSVC-compatible exception handling support. Most of the middle-end and none of the back-end haven't been audited or updated to take them into account. Differential Revision: http://reviews.llvm.org/D11097 llvm-svn: 243766
* Revert the new EH instructionsDavid Majnemer2015-07-101-5/+5
| | | | | | This reverts commits r241888-r241891, I didn't mean to commit them. llvm-svn: 241893
* New EH representation for MSVC compatibilityDavid Majnemer2015-07-101-5/+5
| | | | | | | | | | | | | | | Summary: This introduces new instructions neccessary to implement MSVC-compatible exception handling support. Most of the middle-end and none of the back-end haven't been audited or updated to take them into account. Reviewers: rnk, JosephTremoulet, reames, nlewycky, rjmccall Subscribers: llvm-commits Differential Revision: http://reviews.llvm.org/D11041 llvm-svn: 241888
* Revert "Revert r241570, it caused PR24053"David Majnemer2015-07-071-2/+1
| | | | | | | | This reverts commit r241602. We had a latent bug in SCCP where we would make a basic block empty and then proceed to ask questions about it's terminator. llvm-svn: 241616
* [SCCP] Turn loads of null into undef instead of zero initialized valuesDavid Majnemer2015-07-011-1/+1
| | | | | | | | | | Surprisingly, this is a correctness issue: the mmx type exists for calling convention purposes, LLVM doesn't have a zero representation for them. This partially fixes PR23999. llvm-svn: 241142
* [opaque pointer type] API migration for GEP constant factoriesDavid Blaikie2015-04-021-1/+2
| | | | | | | | | | | | | Require the pointee type to be passed explicitly and assert that it is correct. For now it's possible to pass nullptr here (and I've done so in a few places in this patch) but eventually that will be disallowed once all clients have been updated or removed. It'll be a long road to get all the way there... but if you have the cahnce to update your callers to pass the type explicitly without depending on a pointer's element type, that would be a good thing to do soon and a necessary thing to do eventually. llvm-svn: 233938
* Re-sort includes with sort-includes.py and insert raw_ostream.h where it's used.Benjamin Kramer2015-03-231-1/+1
| | | | llvm-svn: 232998
* DataLayout is mandatory, update the API to reflect it with references.Mehdi Amini2015-03-101-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: Now that the DataLayout is a mandatory part of the module, let's start cleaning the codebase. This patch is a first attempt at doing that. This patch is not exactly NFC as for instance some places were passing a nullptr instead of the DataLayout, possibly just because there was a default value on the DataLayout argument to many functions in the API. Even though it is not purely NFC, there is no change in the validation. I turned as many pointer to DataLayout to references, this helped figuring out all the places where a nullptr could come up. I had initially a local version of this patch broken into over 30 independant, commits but some later commit were cleaning the API and touching part of the code modified in the previous commits, so it seemed cleaner without the intermediate state. Test Plan: Reviewers: echristo Subscribers: llvm-commits From: Mehdi Amini <mehdi.amini@apple.com> llvm-svn: 231740
* Make DataLayout Non-Optional in the ModuleMehdi Amini2015-03-041-8/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: DataLayout keeps the string used for its creation. As a side effect it is no longer needed in the Module. This is "almost" NFC, the string is no longer canonicalized, you can't rely on two "equals" DataLayout having the same string returned by getStringRepresentation(). Get rid of DataLayoutPass: the DataLayout is in the Module The DataLayout is "per-module", let's enforce this by not duplicating it more than necessary. One more step toward non-optionality of the DataLayout in the module. Make DataLayout Non-Optional in the Module Module->getDataLayout() will never returns nullptr anymore. Reviewers: echristo Subscribers: resistor, llvm-commits, jholewinski Differential Revision: http://reviews.llvm.org/D7992 From: Mehdi Amini <mehdi.amini@apple.com> llvm-svn: 231270
* [PM] Separate the TargetLibraryInfo object from the immutable pass.Chandler Carruth2015-01-151-5/+7
| | | | | | | | | | | | | | The pass is really just a means of accessing a cached instance of the TargetLibraryInfo object, and this way we can re-use that object for the new pass manager as its result. Lots of delta, but nothing interesting happening here. This is the common pattern that is developing to allow analyses to live in both the old and new pass manager -- a wrapper pass in the old pass manager emulates the separation intrinsic to the new pass manager between the result and pass for analyses. llvm-svn: 226157
* [PM] Move TargetLibraryInfo into the Analysis library.Chandler Carruth2015-01-151-1/+1
| | | | | | | | | | | | | | | | While the term "Target" is in the name, it doesn't really have to do with the LLVM Target library -- this isn't an abstraction which LLVM targets generally need to implement or extend. It has much more to do with modeling the various runtime libraries on different OSes and with different runtime environments. The "target" in this sense is the more general sense of a target of cross compilation. This is in preparation for porting this analysis to the new pass manager. No functionality changed, and updates inbound for Clang and Polly. llvm-svn: 226078
* Update SetVector to rely on the underlying set's insert to return a ↵David Blaikie2014-11-191-1/+2
| | | | | | | | | | | | | pair<iterator, bool> This is to be consistent with StringSet and ultimately with the standard library's associative container insert function. This lead to updating SmallSet::insert to return pair<iterator, bool>, and then to update SmallPtrSet::insert to return pair<iterator, bool>, and then to update all the existing users of those functions... llvm-svn: 222334
* SCCP: overdefined calls cannot become constantDavid Majnemer2014-11-071-0/+3
| | | | | | | | | | We would attempt to fold away a call instruction which had been marked overdefined. However, it's not valid to transition to constant from overdefined. This fixes PR21512. llvm-svn: 221513
* Simplify creation of a bunch of ArrayRefs by using None, makeArrayRef or ↵Craig Topper2014-08-271-1/+1
| | | | | | just letting them be implicitly created. llvm-svn: 216525
* SCCP: update for cmpxchg returning { iN, i1 } now.Tim Northover2014-06-131-1/+3
| | | | | | I accidentally missed this one since its use looked OK locally. llvm-svn: 210909
* [C++] Use 'nullptr'.Craig Topper2014-04-281-1/+1
| | | | llvm-svn: 207394
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