Commit Graph

136 Commits

Author SHA1 Message Date
Chandler Carruth 70c61c1a8a [PM/AA] Start refactoring AliasAnalysis to remove the analysis group and
port it to the new pass manager.

All this does is extract the inner "location" class used by AA into its
own full fledged type. This seems *much* cleaner as MemoryDependence and
soon MemorySSA also use this heavily, and it doesn't make much sense
being inside the AA infrastructure.

This will also make it much easier to break apart the AA infrastructure
into something that stands on its own rather than using the analysis
group design.

There are a few places where this makes APIs not make sense -- they were
taking an AliasAnalysis pointer just to build locations. I'll try to
clean those up in follow-up commits.

Differential Revision: http://reviews.llvm.org/D10228

llvm-svn: 239003
2015-06-04 02:03:15 +00:00
Teresa Johnson bbcf75e59e Test commit: Remove unnecessary spaces.
llvm-svn: 237259
2015-05-13 15:04:14 +00:00
Daniel Berlin ec1de3fb19 Make getModRefInfo(Instruction *) not crash on certain types of instructions
llvm-svn: 236023
2015-04-28 19:19:14 +00:00
Daniel Berlin 8de312d2a9 Add new getModRefInfo API to determine whether an Instruction and a call modify the same memory
llvm-svn: 234814
2015-04-13 23:25:41 +00:00
Daniel Berlin b2d227693f Make getModRefInfo with a default location not crash.
Add getModRefInfo that works without location.
Add unit tests.

llvm-svn: 234811
2015-04-13 23:05:45 +00:00
Mehdi Amini a28d91d81b DataLayout is mandatory, update the API to reflect it with references.
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
2015-03-10 02:37:25 +00:00
Mehdi Amini 46a43556db Make DataLayout Non-Optional in the Module
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
2015-03-04 18:43:29 +00:00
Chandler Carruth b98f63dbdb [PM] Separate the TargetLibraryInfo object from the immutable pass.
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
2015-01-15 10:41:28 +00:00
Chandler Carruth 62d4215baa [PM] Move TargetLibraryInfo into the Analysis library.
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
2015-01-15 02:16:27 +00:00
Elena Demikhovsky a5599bfd72 Sink store based on alias analysis
- by Ella Bolshinsky
The alias analysis is used define whether the given instruction
is a barrier for store sinking. For 2 identical stores, following
instructions are checked in the both basic blocks, to determine
whether they are sinking barriers.

http://reviews.llvm.org/D6420

llvm-svn: 224247
2014-12-15 14:09:53 +00:00
NAKAMURA Takumi d0e13af22c Reformat partially, where I touched for whitespace changes.
llvm-svn: 220773
2014-10-28 11:54:52 +00:00
NAKAMURA Takumi 335a7bcf1e Untabify and whitespace cleanups.
llvm-svn: 220771
2014-10-28 11:53:30 +00:00
Benjamin Kramer 2e52f02864 Make AAMDNodes ctor and operator bool (!!!) explicit, mop up bugs and weirdness exposed by it.
llvm-svn: 219068
2014-10-04 22:44:29 +00:00
Hal Finkel cc39b67530 AA metadata refactoring (introduce AAMDNodes)
In order to enable the preservation of noalias function parameter information
after inlining, and the representation of block-level __restrict__ pointer
information (etc.), additional kinds of aliasing metadata will be introduced.
This metadata needs to be carried around in AliasAnalysis::Location objects
(and MMOs at the SDAG level), and so we need to generalize the current scheme
(which is hard-coded to just one TBAA MDNode*).

This commit introduces only the necessary refactoring to allow for the
introduction of other aliasing metadata types, but does not actually introduce
any (that will come in a follow-up commit). What it does introduce is a new
AAMDNodes structure to hold all of the aliasing metadata nodes associated with
a particular memory-accessing instruction, and uses that structure instead of
the raw MDNode* in AliasAnalysis::Location, etc.

No functionality change intended.

llvm-svn: 213859
2014-07-24 12:16:19 +00:00
Hal Finkel d32803b669 Match semantics of PointerMayBeCapturedBefore to its name by default
As it turns out, the capture tracker named CaptureBefore used by AA, and now
available via the PointerMayBeCapturedBefore function, would have been
more-aptly named CapturedBeforeOrAt, because it considers captures at the
instruction provided. This is not always what one wants, and it is difficult to
get the strictly-before behavior given only the current interface. This adds an
additional parameter which controls whether or not you want to include
captures at the provided instruction. The default is not to include the
instruction provided, so that 'Before' matches its name.

No functionality change intended.

llvm-svn: 213582
2014-07-21 21:30:22 +00:00
Hal Finkel b035621720 Move the CapturesBefore tracker from AA into CaptureTracking
There were two generally-useful CaptureTracker classes defined in LLVM: the
simple tracker defined in CaptureTracking (and made available via the
PointerMayBeCaptured utility function), and the CapturesBefore tracker
available only inside of AA. This change moves the CapturesBefore tracker into
CaptureTracking, generalizes it slightly (by adding a ReturnCaptures
parameter), and makes it generally available via a PointerMayBeCapturedBefore
utility function.

This logic will be needed, for example, to perform noalias function parameter
attribute inference.

No functionality change intended.

llvm-svn: 213519
2014-07-21 13:15:48 +00:00
Hal Finkel c782aa5a9b Move isIdentifiedFunctionLocal from BasicAA to AA
The ability to identify function locals will exist outside of BasicAA (for
example, logic for inferring noalias function arguments will need this), so
make this concept generally accessible without code duplication.

No functionality change.

llvm-svn: 213514
2014-07-21 12:27:23 +00:00
Hal Finkel 354e23b029 Improve BasicAA CS-CS queries (redux)
This reverts, "r213024 - Revert r212572 "improve BasicAA CS-CS queries", it
causes PR20303." with a fix for the bug in pr20303. As it turned out, the
relevant code was both wrong and over-conservative (because, as with the code
it replaced, it would return the overall ModRef mask even if just Ref had been
implied by the argument aliasing results). Hopefully, this correctly fixes both
problems.

Thanks to Nick Lewycky for reducing the test case for pr20303 (which I've
cleaned up a little and added in DSE's test directory). The BasicAA test has
also been updated to check for this error.

Original commit message:

BasicAA contains knowledge of certain intrinsics, such as memcpy and memset,
and uses that information to form more-accurate answers to CallSite vs. Loc
ModRef queries. Unfortunately, it did not use this information when answering
CallSite vs. CallSite queries.

Generically, when an intrinsic takes one or more pointers and the intrinsic is
marked only to read/write from its arguments, the offset/size is unknown. As a
result, the generic code that answers CallSite vs. CallSite (and CallSite vs.
Loc) queries in AA uses UnknownSize when forming Locs from an intrinsic's
arguments. While BasicAA's CallSite vs. Loc override could use more-accurate
size information for some intrinsics, it did not do the same for CallSite vs.
CallSite queries.

This change refactors the intrinsic-specific logic in BasicAA into a generic AA
query function: getArgLocation, which is overridden by BasicAA to supply the
intrinsic-specific knowledge, and used by AA's generic implementation. This
allows the intrinsic-specific knowledge to be used by both CallSite vs. Loc and
CallSite vs. CallSite queries, and simplifies the BasicAA implementation.

Currently, only one function, Mac's memset_pattern16, is handled by BasicAA
(all the rest are intrinsics). As a side-effect of this refactoring, BasicAA's
getModRefBehavior override now also returns OnlyAccessesArgumentPointees for
this function (which is an improvement).

llvm-svn: 213219
2014-07-17 01:28:25 +00:00
Nick Lewycky 7a63c3b389 Revert r212572 "improve BasicAA CS-CS queries", it causes PR20303.
llvm-svn: 213024
2014-07-15 00:53:38 +00:00
Hal Finkel 8ae0f8d618 Improve BasicAA CS-CS queries
BasicAA contains knowledge of certain intrinsics, such as memcpy and memset,
and uses that information to form more-accurate answers to CallSite vs. Loc
ModRef queries. Unfortunately, it did not use this information when answering
CallSite vs. CallSite queries.

Generically, when an intrinsic takes one or more pointers and the intrinsic is
marked only to read/write from its arguments, the offset/size is unknown. As a
result, the generic code that answers CallSite vs. CallSite (and CallSite vs.
Loc) queries in AA uses UnknownSize when forming Locs from an intrinsic's
arguments. While BasicAA's CallSite vs. Loc override could use more-accurate
size information for some intrinsics, it did not do the same for CallSite vs.
CallSite queries.

This change refactors the intrinsic-specific logic in BasicAA into a generic AA
query function: getArgLocation, which is overridden by BasicAA to supply the
intrinsic-specific knowledge, and used by AA's generic implementation. This
allows the intrinsic-specific knowledge to be used by both CallSite vs. Loc and
CallSite vs. CallSite queries, and simplifies the BasicAA implementation.

Currently, only one function, Mac's memset_pattern16, is handled by BasicAA
(all the rest are intrinsics). As a side-effect of this refactoring, BasicAA's
getModRefBehavior override now also returns OnlyAccessesArgumentPointees for
this function (which is an improvement).

llvm-svn: 212572
2014-07-08 23:16:49 +00:00
Craig Topper 9f008867c0 [C++11] More 'nullptr' conversion. In some cases just using a boolean check instead of comparing to nullptr.
llvm-svn: 206243
2014-04-15 04:59:12 +00:00
Tim Northover e94a518a22 IR: add a second ordering operand to cmpxhg for failure
The syntax for "cmpxchg" should now look something like:

	cmpxchg i32* %addr, i32 42, i32 3 acquire monotonic

where the second ordering argument gives the required semantics in the case
that no exchange takes place. It should be no stronger than the first ordering
constraint and cannot be either "release" or "acq_rel" (since no store will
have taken place).

rdar://problem/15996804

llvm-svn: 203559
2014-03-11 10:48:52 +00:00
Chandler Carruth 64e9aa5c93 [C++11] Make this interface accept const Use pointers and use override
to ensure we don't mess up any of the overrides. Necessary for cleaning
up the Value use iterators and enabling range-based traversing of use
lists.

llvm-svn: 202958
2014-03-05 10:21:48 +00:00
Craig Topper e9ba759c81 [C++11] Add 'override' keyword to virtual methods that override their base class.
llvm-svn: 202945
2014-03-05 07:30:04 +00:00
Rafael Espindola 935125126c Make DataLayout a plain object, not a pass.
Instead, have a DataLayoutPass that holds one. This will allow parts of LLVM
don't don't handle passes to also use DataLayout.

llvm-svn: 202168
2014-02-25 17:30:31 +00:00
Rafael Espindola 7c68bebb9c Rename some member variables from TD to DL.
TargetData was renamed DataLayout back in r165242.

llvm-svn: 201581
2014-02-18 15:33:12 +00:00
Chandler Carruth 5ad5f15cff [cleanup] Move the Dominators.h and Verifier.h headers into the IR
directory. These passes are already defined in the IR library, and it
doesn't make any sense to have the headers in Analysis.

Long term, I think there is going to be a much better way to divide
these matters. The dominators code should be fully separated into the
abstract graph algorithm and have that put in Support where it becomes
obvious that evn Clang's CFGBlock's can use it. Then the verifier can
manually construct dominance information from the Support-driven
interface while the Analysis library can provide a pass which both
caches, reconstructs, and supports a nice update API.

But those are very long term, and so I don't want to leave the really
confusing structure until that day arrives.

llvm-svn: 199082
2014-01-13 09:26:24 +00:00
Chandler Carruth 8a8cd2bab9 Re-sort all of the includes with ./utils/sort_includes.py so that
subsequent changes are easier to review. About to fix some layering
issues, and wanted to separate out the necessary churn.

Also comment and sink the include of "Windows.h" in three .inc files to
match the usage in Memory.inc.

llvm-svn: 198685
2014-01-07 11:48:04 +00:00
Nick Lewycky 0b68245ec8 Reimplement isPotentiallyReachable to make nocapture deduction much stronger.
Adds unit tests for it too.

Split BasicBlockUtils into an analysis-half and a transforms-half, and put the
analysis bits into a new Analysis/CFG.{h,cpp}. Promote isPotentiallyReachable
into llvm::isPotentiallyReachable and move it into Analysis/CFG.

llvm-svn: 187283
2013-07-27 01:24:00 +00:00
Nick Lewycky 0dcefdfcab Give 'hasPath' a longer but clearer name 'isPotentiallyReachable'. Also expand
the comment. No functionality change. This change broken out of
http://llvm-reviews.chandlerc.com/D996 .

llvm-svn: 186558
2013-07-18 02:34:51 +00:00
Nick Lewycky c0514629c9 Eliminate trivial redundant loads across nocapture+readonly calls to uncaptured
pointer arguments.

llvm-svn: 185776
2013-07-07 10:15:16 +00:00
Michael Kuperstein f3e663af39 Make BasicAliasAnalysis recognize the fact a noalias argument cannot alias another argument, even if the other argument is not itself marked noalias.
llvm-svn: 182755
2013-05-28 08:17:48 +00:00
Dan Gohman 1b0f79de0a Move isKnownNonNull out of AliasAnalysis.h and into ValueTracking.cpp since
it isn't really an AliasAnalysis concept, and ValueTracking has similar things
that it could plausibly share code with some day.

llvm-svn: 174027
2013-01-31 02:40:59 +00:00
Manman Ren fe5a61edbe Memory Dependence Analysis: fix a miscompile that uses DT to approxmiate the
reachablity.

We conservatively approximate the reachability analysis by saying it is not
reachable if there is a single path starting from "From" and the path does not
reach "To".

rdar://12801584

llvm-svn: 171512
2013-01-04 19:19:47 +00:00
Chandler Carruth 9fb823bbd4 Move all of the header files which are involved in modelling the LLVM IR
into their new header subdirectory: include/llvm/IR. This matches the
directory structure of lib, and begins to correct a long standing point
of file layout clutter in LLVM.

There are still more header files to move here, but I wanted to handle
them in separate commits to make tracking what files make sense at each
layer easier.

The only really questionable files here are the target intrinsic
tablegen files. But that's a battle I'd rather not fight today.

I've updated both CMake and Makefile build systems (I think, and my
tests think, but I may have missed something).

I've also re-sorted the includes throughout the project. I'll be
committing updates to Clang, DragonEgg, and Polly momentarily.

llvm-svn: 171366
2013-01-02 11:36:10 +00:00
Bill Wendling 3d7b0b8ac7 Rename the 'Attributes' class to 'Attribute'. It's going to represent a single attribute in the future.
llvm-svn: 170502
2012-12-19 07:18:57 +00:00
Chandler Carruth ed0881b2a6 Use the new script to sort the includes of every file under lib.
Sooooo many of these had incorrect or strange main module includes.
I have manually inspected all of these, and fixed the main module
include to be the nearest plausible thing I could find. If you own or
care about any of these source files, I encourage you to take some time
and check that these edits were sensible. I can't have broken anything
(I strictly added headers, and reordered them, never removed), but they
may not be the headers you'd really like to identify as containing the
API being implemented.

Many forward declarations and missing includes were added to a header
files to allow them to parse cleanly when included first. The main
module rule does in fact have its merits. =]

llvm-svn: 169131
2012-12-03 16:50:05 +00:00
Bill Wendling 8ccd6ca199 Use the attribute enums to query if a parameter has an attribute.
llvm-svn: 165550
2012-10-09 21:38:14 +00:00
Micah Villmow cdfe20b97f Move TargetData to DataLayout.
llvm-svn: 165402
2012-10-08 16:38:25 +00:00
Bill Wendling 5d637b7d5b Use method to query for NoAlias attribute.
llvm-svn: 165211
2012-10-04 07:17:46 +00:00
Benjamin Kramer 8bcc971174 Make MemoryBuiltins aware of TargetLibraryInfo.
This disables malloc-specific optimization when -fno-builtin (or -ffreestanding)
is specified. This has been a problem for a long time but became more severe
with the recent memory builtin improvements.

Since the memory builtin functions are used everywhere, this required passing
TLI in many places. This means that functions that now have an optional TLI
argument, like RecursivelyDeleteTriviallyDeadFunctions, won't remove dead
mallocs anymore if the TLI argument is missing. I've updated most passes to do
the right thing.

Fixes PR13694 and probably others.

llvm-svn: 162841
2012-08-29 15:32:21 +00:00
Chad Rosier a968caf8e0 Move the capture analysis from MemoryDependencyAnalysis to a more general place
so that it can be reused in MemCpyOptimizer.  This analysis is needed to remove
an unnecessary memcpy when returning a struct into a local variable.
rdar://11341081
PR12686

llvm-svn: 156776
2012-05-14 20:35:04 +00:00
Nick Lewycky 3f885b65a2 Move isKnownNonNull from private implementation detail of BasicAA to a public
function that others can use, next to llvm::isIdentifiedObject.

llvm-svn: 151446
2012-02-25 10:56:28 +00:00
Eli Friedman 5c91891cf3 Enhance alias analysis for atomic instructions a bit. Upgrade a couple alias-analysis tests to the new atomic instructions.
llvm-svn: 140557
2011-09-26 20:15:28 +00:00
Eli Friedman 5494adac67 Misc analysis passes that need to be aware of atomic load/store.
llvm-svn: 137650
2011-08-15 20:54:19 +00:00
Chris Lattner 229907cd11 land David Blaikie's patch to de-constify Type, with a few tweaks.
llvm-svn: 135375
2011-07-18 04:54:35 +00:00
Dan Gohman 39b3a1ef7f When analyzing functions known to only access argument pointees,
only check arguments with pointer types. Update the documentation
of IntrReadArgMem reflect this.

While here, add support for TBAA tags on intrinsic calls.

llvm-svn: 130317
2011-04-27 18:39:03 +00:00
Owen Anderson b6e4ff0d85 Stub out a new updating interface to AliasAnalysis, allowing stateful analyses to be informed when
a pointer value has potentially become escaping.  Implementations can choose to either fall back to
conservative responses for that value, or may recompute their analysis to accomodate the change.

llvm-svn: 122777
2011-01-03 21:38:41 +00:00
Dan Gohman e1a17a3473 Make memcpyopt TBAA-aware.
llvm-svn: 121944
2010-12-16 02:51:19 +00:00
Chris Lattner afbc0c2b8c getLocationForDest should work for memset as well.
llvm-svn: 120380
2010-11-30 01:48:20 +00:00