Commit Graph

60 Commits

Author SHA1 Message Date
Bjorn Pettersson 675be65106 Require chained analyses in BasicAA and AAResults to be transitive
This patch fixes a bug that could result in miscompiles (at least
in an OOT target). The problem could be seen by adding checks that
the DominatorTree used in BasicAliasAnalysis and ValueTracking was
valid (e.g. by adding DT->verify() call before every DT dereference
and then running all tests in test/CodeGen).

Problem was that the LegacyPassManager calculated "last user"
incorrectly for passes such as the DominatorTree when not telling
the pass manager that there was a transitive dependency between
the different analyses. And then it could happen that an incorrect
dominator tree was used when doing alias analysis (which was a pretty
serious bug as the alias analysis result could be invalid).

Fixes: https://bugs.llvm.org/show_bug.cgi?id=48709

Reviewed By: nikic

Differential Revision: https://reviews.llvm.org/D94138
2021-01-11 11:50:07 +01:00
Oliver Stannard 76f6b125ce Revert "[llvm] Use BasicBlock::phis() (NFC)"
Reverting because this causes crashes on the 2-stage buildbots, for
example http://lab.llvm.org:8011/#/builders/7/builds/1140.

This reverts commit 9b228f107d.
2021-01-07 09:43:33 +00:00
Kazu Hirata 9b228f107d [llvm] Use BasicBlock::phis() (NFC) 2021-01-06 18:27:35 -08:00
Nikita Popov 4df8efce80 [AA] Split up LocationSize::unknown()
Currently, we have some confusion in the codebase regarding the
meaning of LocationSize::unknown(): Some parts (including most of
BasicAA) assume that LocationSize::unknown() only allows accesses
after the base pointer. Some parts (various callers of AA) assume
that LocationSize::unknown() allows accesses both before and after
the base pointer (but within the underlying object).

This patch splits up LocationSize::unknown() into
LocationSize::afterPointer() and LocationSize::beforeOrAfterPointer()
to make this completely unambiguous. I tried my best to determine
which one is appropriate for all the existing uses.

The test changes in cs-cs.ll in particular illustrate a previously
clearly incorrect AA result: We were effectively assuming that
argmemonly functions were only allowed to access their arguments
after the passed pointer, but not before it. I'm pretty sure that
this was not intentional, and it's certainly not specified by
LangRef that way.

Differential Revision: https://reviews.llvm.org/D91649
2020-11-26 18:39:55 +01:00
Arthur Eubanks ac7419bb4f [Hexagon][NewPM] Port -hexagon-loop-idiom and add to pipeline
Fixes pmpy-mod.ll under NPM

Reviewed By: kparzysz

Differential Revision: https://reviews.llvm.org/D91829
2020-11-20 09:34:37 -08:00
Florian Hahn bcbd26bfe6 [SCEV] Move ScalarEvolutionExpander.cpp to Transforms/Utils (NFC).
SCEVExpander modifies the underlying function so it is more suitable in
Transforms/Utils, rather than Analysis. This allows using other
transform utils in SCEVExpander.

This patch was originally committed as b8a3c34eee, but broke the
modules build, as LoopAccessAnalysis was using the Expander.

The code-gen part of LAA was moved to lib/Transforms recently, so this
patch can be landed again.

Reviewers: sanjoy.google, efriedma, reames

Reviewed By: sanjoy.google

Differential Revision: https://reviews.llvm.org/D71537
2020-05-20 10:53:40 +01:00
Florian Hahn b8a3c34eee Revert "[SCEV] Move ScalarEvolutionExpander.cpp to Transforms/Utils (NFC)."
This reverts commit 51ef53f3bd, as it
breaks some bots.
2020-01-04 18:44:38 +00:00
Florian Hahn 51ef53f3bd [SCEV] Move ScalarEvolutionExpander.cpp to Transforms/Utils (NFC).
SCEVExpander modifies the underlying function so it is more suitable in
Transforms/Utils, rather than Analysis. This allows using other
transform utils in SCEVExpander.

Reviewers: sanjoy.google, efriedma, reames

Reviewed By: sanjoy.google

Differential Revision: https://reviews.llvm.org/D71537
2020-01-04 18:29:35 +00:00
Mark de Wever 9c11026c1b [Hexagon] Fixes -Wrange-loop-analysis warnings
This avoids new warnings due to D68912 adds -Wrange-loop-analysis to -Wall.

Differential Revision: https://reviews.llvm.org/D71814
2019-12-22 19:35:02 +01:00
Guillaume Chatelet 531c1161b9 Resubmit "[Alignment][NFC] Deprecate CreateMemCpy/CreateMemMove"
Summary:
This is a resubmit of D71473.

This patch introduces a set of functions to enable deprecation of IRBuilder functions without breaking out of tree clients.
Functions will be deprecated one by one and as in tree code is cleaned up.

This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: aaron.ballman, courbet

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71547
2019-12-17 10:07:46 +01:00
Guillaume Chatelet 4658da10e4 Revert "[Alignment][NFC] Deprecate CreateMemCpy/CreateMemMove"
This reverts commit 181ab91efc.
2019-12-16 15:19:49 +01:00
Guillaume Chatelet 181ab91efc [Alignment][NFC] Deprecate CreateMemCpy/CreateMemMove
Summary:
This patch introduces a set of functions to enable deprecation of IRBuilder functions without breaking out of tree clients.
Functions will be deprecated one by one and as in tree code is cleaned up.

This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: arsenm, jvesely, nhaehnle, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71473
2019-12-16 13:35:55 +01:00
Reid Kleckner 5d986953c8 [IR] Split out target specific intrinsic enums into separate headers
This has two main effects:
- Optimizes debug info size by saving 221.86 MB of obj file size in a
  Windows optimized+debug build of 'all'. This is 3.03% of 7,332.7MB of
  object file size.
- Incremental step towards decoupling target intrinsics.

The enums are still compact, so adding and removing a single
target-specific intrinsic will trigger a rebuild of all of LLVM.
Assigning distinct target id spaces is potential future work.

Part of PR34259

Reviewers: efriedma, echristo, MaskRay

Reviewed By: echristo, MaskRay

Differential Revision: https://reviews.llvm.org/D71320
2019-12-11 18:02:14 -08:00
Reid Kleckner 05da2fe521 Sink all InitializePasses.h includes
This file lists every pass in LLVM, and is included by Pass.h, which is
very popular. Every time we add, remove, or rename a pass in LLVM, it
caused lots of recompilation.

I found this fact by looking at this table, which is sorted by the
number of times a file was changed over the last 100,000 git commits
multiplied by the number of object files that depend on it in the
current checkout:
  recompiles    touches affected_files  header
  342380        95      3604    llvm/include/llvm/ADT/STLExtras.h
  314730        234     1345    llvm/include/llvm/InitializePasses.h
  307036        118     2602    llvm/include/llvm/ADT/APInt.h
  213049        59      3611    llvm/include/llvm/Support/MathExtras.h
  170422        47      3626    llvm/include/llvm/Support/Compiler.h
  162225        45      3605    llvm/include/llvm/ADT/Optional.h
  158319        63      2513    llvm/include/llvm/ADT/Triple.h
  140322        39      3598    llvm/include/llvm/ADT/StringRef.h
  137647        59      2333    llvm/include/llvm/Support/Error.h
  131619        73      1803    llvm/include/llvm/Support/FileSystem.h

Before this change, touching InitializePasses.h would cause 1345 files
to recompile. After this change, touching it only causes 550 compiles in
an incremental rebuild.

Reviewers: bkramer, asbirlea, bollu, jdoerfert

Differential Revision: https://reviews.llvm.org/D70211
2019-11-13 16:34:37 -08:00
Simon Pilgrim 92fb382074 HexagonLoopIdiomRecognition - silence static analyzer dyn_cast<> null dereference warnings. NFCI.
llvm-svn: 372619
2019-09-23 15:36:24 +00:00
Teresa Johnson 9c27b59cec Change TargetLibraryInfo analysis passes to always require Function
Summary:
This is the first change to enable the TLI to be built per-function so
that -fno-builtin* handling can be migrated to use function attributes.
See discussion on D61634 for background. This is an enabler for fixing
handling of these options for LTO, for example.

This change should not affect behavior, as the provided function is not
yet used to build a specifically per-function TLI, but rather enables
that migration.

Most of the changes were very mechanical, e.g. passing a Function to the
legacy analysis pass's getTLI interface, or in Module level cases,
adding a callback. This is similar to the way the per-function TTI
analysis works.

There was one place where we were looking for builtins but not in the
context of a specific function. See FindCXAAtExit in
lib/Transforms/IPO/GlobalOpt.cpp. I'm somewhat concerned my workaround
could provide the wrong behavior in some corner cases. Suggestions
welcome.

Reviewers: chandlerc, hfinkel

Subscribers: arsenm, dschuff, jvesely, nhaehnle, mehdi_amini, javed.absar, sbc100, jgravelle-google, eraman, aheejin, steven_wu, george.burgess.iv, dexonsmith, jfb, asbirlea, gchatelet, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66428

llvm-svn: 371284
2019-09-07 03:09:36 +00:00
Benjamin Kramer dc5f805d31 Do a sweep of symbol internalization. NFC.
llvm-svn: 369803
2019-08-23 19:59:23 +00:00
James Y Knight 7976eb5838 [opaque pointer types] Pass function types to CallInst creation.
This cleans up all CallInst creation in LLVM to explicitly pass a
function type rather than deriving it from the pointer's element-type.

Differential Revision: https://reviews.llvm.org/D57170

llvm-svn: 352909
2019-02-01 20:43:25 +00:00
James Y Knight 13680223b9 [opaque pointer types] Add a FunctionCallee wrapper type, and use it.
Recommit r352791 after tweaking DerivedTypes.h slightly, so that gcc
doesn't choke on it, hopefully.

Original Message:
The FunctionCallee type is effectively a {FunctionType*,Value*} pair,
and is a useful convenience to enable code to continue passing the
result of getOrInsertFunction() through to EmitCall, even once pointer
types lose their pointee-type.

Then:
- update the CallInst/InvokeInst instruction creation functions to
  take a Callee,
- modify getOrInsertFunction to return FunctionCallee, and
- update all callers appropriately.

One area of particular note is the change to the sanitizer
code. Previously, they had been casting the result of
`getOrInsertFunction` to a `Function*` via
`checkSanitizerInterfaceFunction`, and storing that. That would report
an error if someone had already inserted a function declaraction with
a mismatching signature.

However, in general, LLVM allows for such mismatches, as
`getOrInsertFunction` will automatically insert a bitcast if
needed. As part of this cleanup, cause the sanitizer code to do the
same. (It will call its functions using the expected signature,
however they may have been declared.)

Finally, in a small number of locations, callers of
`getOrInsertFunction` actually were expecting/requiring that a brand
new function was being created. In such cases, I've switched them to
Function::Create instead.

Differential Revision: https://reviews.llvm.org/D57315

llvm-svn: 352827
2019-02-01 02:28:03 +00:00
James Y Knight fadf25068e Revert "[opaque pointer types] Add a FunctionCallee wrapper type, and use it."
This reverts commit f47d6b38c7 (r352791).

Seems to run into compilation failures with GCC (but not clang, where
I tested it). Reverting while I investigate.

llvm-svn: 352800
2019-01-31 21:51:58 +00:00
James Y Knight f47d6b38c7 [opaque pointer types] Add a FunctionCallee wrapper type, and use it.
The FunctionCallee type is effectively a {FunctionType*,Value*} pair,
and is a useful convenience to enable code to continue passing the
result of getOrInsertFunction() through to EmitCall, even once pointer
types lose their pointee-type.

Then:
- update the CallInst/InvokeInst instruction creation functions to
  take a Callee,
- modify getOrInsertFunction to return FunctionCallee, and
- update all callers appropriately.

One area of particular note is the change to the sanitizer
code. Previously, they had been casting the result of
`getOrInsertFunction` to a `Function*` via
`checkSanitizerInterfaceFunction`, and storing that. That would report
an error if someone had already inserted a function declaraction with
a mismatching signature.

However, in general, LLVM allows for such mismatches, as
`getOrInsertFunction` will automatically insert a bitcast if
needed. As part of this cleanup, cause the sanitizer code to do the
same. (It will call its functions using the expected signature,
however they may have been declared.)

Finally, in a small number of locations, callers of
`getOrInsertFunction` actually were expecting/requiring that a brand
new function was being created. In such cases, I've switched them to
Function::Create instead.

Differential Revision: https://reviews.llvm.org/D57315

llvm-svn: 352791
2019-01-31 20:35:56 +00:00
Chandler Carruth 2946cd7010 Update the file headers across all of the LLVM projects in the monorepo
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
2019-01-19 08:50:56 +00:00
Krzysztof Parzyszek 4121eaf0a5 [Hexagon] Do not promote terminator instructions in Hexagon loop idioms
llvm-svn: 351369
2019-01-16 19:40:27 +00:00
George Burgess IV 7e12875c89 [LoopIdioms] More LocationSize::precise annotations; NFC
Both of these places reference memset-like loops. Memset is precise.

Trying to keep these patches super small so they're easily post-commit
verifiable, as requested in D44748.

llvm-svn: 350044
2018-12-24 05:55:50 +00:00
Fangrui Song 2e83b2e9ee Use llvm::{all,any,none}_of instead std::{all,any,none}_of. NFC
llvm-svn: 344774
2018-10-19 06:12:02 +00:00
George Burgess IV 6ef8002c2c Replace most users of UnknownSize with LocationSize::unknown(); NFC
Moving away from UnknownSize is part of the effort to migrate us to
LocationSizes (e.g. the cleanup promised in D44748).

This doesn't entirely remove all of the uses of UnknownSize; some uses
require tweaks to assume that UnknownSize isn't just some kind of int.
This patch is intended to just be a trivial replacement for all places
where LocationSize::unknown() will Just Work.

llvm-svn: 344186
2018-10-10 21:28:44 +00:00
David Blaikie 31b98d2e99 Move Analysis/Utils/Local.h back to Transforms
Review feedback from r328165. Split out just the one function from the
file that's used by Analysis. (As chandlerc pointed out, the original
change only moved the header and not the implementation anyway - which
was fine for the one function that was used (since it's a
template/inlined in the header) but not in general)

llvm-svn: 333954
2018-06-04 21:23:21 +00:00
George Burgess IV 319be3a4e6 Replace AA's uses of uint64_t with LocationSize; NFC.
The uint64_ts that we pass around AA to represent MemoryLocation sizes
are logically an Optional<uint64_t>. In D44748, we want to add an extra
'imprecise' bit to this Optional<uint64_t> to represent whether a given
MemoryLocation size is an upper-bound or an exact size. For more context
on why, please see D44748.

That patch is quite large, but reviewers seem to be OK with the
approach. In D45581 (my first attempt to split 'noise' out of D44748),
reames asked that I land a precursor that is solely replacing uint64_t
with LocationSize, which starts out as `using LocationSize = uint64_t;`.
He also gave me the OK to submit this rename without further review.

llvm-svn: 333314
2018-05-25 21:16:58 +00:00
Nicola Zaghen d34e60ca85 Rename DEBUG macro to LLVM_DEBUG.
The DEBUG() macro is very generic so it might clash with other projects.
The renaming was done as follows:
- git grep -l 'DEBUG' | xargs sed -i 's/\bDEBUG\s\?(/LLVM_DEBUG(/g'
- git diff -U0 master | ../clang/tools/clang-format/clang-format-diff.py -i -p1 -style LLVM
- Manual change to APInt
- Manually chage DOCS as regex doesn't match it.

In the transition period the DEBUG() macro is still present and aliased
to the LLVM_DEBUG() one.

Differential Revision: https://reviews.llvm.org/D43624

llvm-svn: 332240
2018-05-14 12:53:11 +00:00
Fangrui Song 862eebb6d6 Simplify LLVM_ATTRIBUTE_USED call sites.
llvm-svn: 331599
2018-05-05 20:14:38 +00:00
Adrian Prantl 5f8f34e459 Remove \brief commands from doxygen comments.
We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.

Patch produced by

  for i in $(git grep -l '\\brief'); do perl -pi -e 's/\\brief //g' $i & done

Differential Revision: https://reviews.llvm.org/D46290

llvm-svn: 331272
2018-05-01 15:54:18 +00:00
David Blaikie a373d18eb7 Transforms: Introduce Transforms/Utils.h rather than spreading the declarations amongst Scalar.h and IPO.h
Fixes layering - Transforms/Utils shouldn't depend on including a Scalar
or IPO header, because Scalar and IPO depend on Utils.

llvm-svn: 328717
2018-03-28 17:44:36 +00:00
David Blaikie 2be3922807 Fix a couple of layering violations in Transforms
Remove #include of Transforms/Scalar.h from Transform/Utils to fix layering.

Transforms depends on Transforms/Utils, not the other way around. So
remove the header and the "createStripGCRelocatesPass" function
declaration (& definition) that is unused and motivated this dependency.

Move Transforms/Utils/Local.h into Analysis because it's used by
Analysis/MemoryBuiltins.cpp.

llvm-svn: 328165
2018-03-21 22:34:23 +00:00
Daniel Neilson f4fa26f5d8 [Hexagon] Update uses of deprecated IRBuilder CreateMemCpy/Move calls
Summary:
This change is part of step five in the series of changes to remove alignment argument from
memcpy/memmove/memset in favour of alignment attributes. In particular, this changes the
Hexagon LoopIdiom pass to cease using the old IRBuilder createMemCpy/createMemMove
single-alignment APIs in favour of the new API that allows setting source and
destination alignments independently.

Steps:
Step 1) Remove alignment parameter and create alignment parameter attributes for
memcpy/memmove/memset. ( rL322965, rC322964, rL322963 )
Step 2) Expand the IRBuilder API to allow creation of memcpy/memmove with differing
source and dest alignments. ( rL323597 )
Step 3) Update Clang to use the new IRBuilder API. ( rC323617 )
Step 4) Update Polly to use the new IRBuilder API. ( rL323618 )
Step 5) Update LLVM passes that create memcpy/memmove calls to use the new IRBuilder API,
and those that use use MemIntrinsicInst::[get|set]Alignment() to use [get|set]DestAlignment()
and [get|set]SourceAlignment() instead. ( rL323886, rL323891, rL324148, rL324273, rL324278,
rL324384, rL324395, rL324402, rL324626, rL324642, rL324653, rL324654, rL324773, rL324774,
rL324781 )
Step 6) Remove the single-alignment IRBuilder API for memcpy/memmove, and the
MemIntrinsicInst::[get|set]Alignment() methods.

Reference
   http://lists.llvm.org/pipermail/llvm-dev/2015-August/089384.html
   http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html

llvm-svn: 324784
2018-02-09 23:33:35 +00:00
Krzysztof Parzyszek 5d9844f48a [Hexagon] Handle truncates in polynomial multiply idiom recognition
This is in anticipation of https://reviews.llvm.org/D42424, which would
otherwise break one of the pmpy testcases.

llvm-svn: 323824
2018-01-30 22:03:59 +00:00
Benjamin Kramer c7fc81e659 Use phi ranges to simplify code. No functionality change intended.
llvm-svn: 321585
2017-12-30 15:27:33 +00:00
Alina Sbirlea 193429f0c8 [ModRefInfo] Make enum ModRefInfo an enum class [NFC].
Summary:
Make enum ModRefInfo an enum class. Changes to ModRefInfo values should
be done using inline wrappers.
This should prevent future bit-wise opearations from being added, which can be more error-prone.

Reviewers: sanjoy, dberlin, hfinkel, george.burgess.iv

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D40933

llvm-svn: 320107
2017-12-07 22:41:34 +00:00
Alina Sbirlea 18fea013de [ModRefInfo] Do not use ModRefInfo result in if conditions as this makes
assumptions about the values in the enum. Replace with wrapper returning
bool [NFC].

llvm-svn: 319949
2017-12-06 19:56:37 +00:00
Alina Sbirlea 63d2250a42 Modify ModRefInfo values using static inline method abstractions [NFC].
Summary:
The aim is to make ModRefInfo checks and changes more intuitive
and less error prone using inline methods that abstract the bit operations.

Ideally ModRefInfo would become an enum class, but that change will require
a wider set of changes into FunctionModRefBehavior.

Reviewers: sanjoy, george.burgess.iv, dberlin, hfinkel

Subscribers: nlopes, llvm-commits

Differential Revision: https://reviews.llvm.org/D40749

llvm-svn: 319821
2017-12-05 20:12:23 +00:00
Jonas Paulsson f0ff20f1f0 Use getStoreSize() in various places instead of 'BitSize >> 3'.
This is needed for cases when the memory access is not as big as the width of
the data type. For instance, storing i1 (1 bit) would be done in a byte (8
bits).

Using 'BitSize >> 3' (or '/ 8') would e.g. give the memory access of an i1 a
size of 0, which for instance makes alias analysis return NoAlias even when
it shouldn't.

There are no tests as this was done as a follow-up to the bugfix for the case
where this was discovered (r318824). This handles more similar cases.

Review: Björn Petterson
https://reviews.llvm.org/D40339

llvm-svn: 319173
2017-11-28 14:44:32 +00:00
Krzysztof Parzyszek 385a4e0489 [Hexagon] Make a test more flexible in HexagonLoopIdiomRecognition
An "or" that sets the sign-bit can be replaced with a "xor", if
the sign-bit was known to be clear before. With some changes to
instruction combining, the simple sign-bit check was failing.
Replace it with a more flexible one to catch more cases.

llvm-svn: 317592
2017-11-07 17:05:54 +00:00
Krzysztof Parzyszek c09a14eeb2 [Hexagon] Generate correct runtime check when recognizing memmove
The check (assuming positive stride) for validity of memmove should be
(a) the destination is at a lower address than the source, or
(b) the distance between the source and destination is greater than or
    equal the number of bytes copied.

For the second part it is sufficient to assume that the destination
is at a higher address, since the opposite case is covered by (a).
The distance calculation was previously done by subtracting the
pointers in the wrong order.

llvm-svn: 311650
2017-08-24 11:59:53 +00:00
Eugene Zelenko 4d060b71cc [Hexagon] Fix some Clang-tidy modernize-use-using and Include What You Use warnings; other minor fixes (NFC).
llvm-svn: 309469
2017-07-29 00:56:56 +00:00
Krzysztof Parzyszek 9bd4d91037 [Hexagon] Stop pmpy recognition when shift conversion fails
The conversion of shifts from right shifts to left shifts may fail.
In such case, the pmpy recognition cannot proceed.

llvm-svn: 305289
2017-06-13 13:51:49 +00:00
Chandler Carruth 6bda14b313 Sort the remaining #include lines in include/... and lib/....
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
2017-06-06 11:49:48 +00:00
Krzysztof Parzyszek 51fd5405d5 [Hexagon] Handle long-running simplification loop in idiom recognition
The initial assumption was that the simplification would converge to a
fixed point relatvely quickly. Turns out that there are legitimate situa-
tions where the complexity of the code causes it to take a large number
of iterations.

Two main changes:
- Instead of aborting upon hitting the limit, simply return nullptr.
- Reduce the limit to 10,000 from 100,000.

llvm-svn: 304441
2017-06-01 18:00:47 +00:00
Reid Kleckner 96ab8726a3 [IR] De-virtualize ~Value to save a vptr
Summary:
Implements PR889

Removing the virtual table pointer from Value saves 1% of RSS when doing
LTO of llc on Linux. The impact on time was positive, but too noisy to
conclusively say that performance improved. Here is a link to the
spreadsheet with the original data:

https://docs.google.com/spreadsheets/d/1F4FHir0qYnV0MEp2sYYp_BuvnJgWlWPhWOwZ6LbW7W4/edit?usp=sharing

This change makes it invalid to directly delete a Value, User, or
Instruction pointer. Instead, such code can be rewritten to a null check
and a call Value::deleteValue(). Value objects tend to have their
lifetimes managed through iplist, so for the most part, this isn't a big
deal.  However, there are some places where LLVM deletes values, and
those places had to be migrated to deleteValue.  I have also created
llvm::unique_value, which has a custom deleter, so it can be used in
place of std::unique_ptr<Value>.

I had to add the "DerivedUser" Deleter escape hatch for MemorySSA, which
derives from User outside of lib/IR. Code in IR cannot include MemorySSA
headers or call the MemoryAccess object destructors without introducing
a circular dependency, so we need some level of indirection.
Unfortunately, no class derived from User may have any virtual methods,
because adding a virtual method would break User::getHungOffOperands(),
which assumes that it can find the use list immediately prior to the
User object. I've added a static_assert to the appropriate OperandTraits
templates to help people avoid this trap.

Reviewers: chandlerc, mehdi_amini, pete, dberlin, george.burgess.iv

Reviewed By: chandlerc

Subscribers: krytarowski, eraman, george.burgess.iv, mzolotukhin, Prazek, nlewycky, hans, inglorion, pcc, tejohnson, dberlin, llvm-commits

Differential Revision: https://reviews.llvm.org/D31261

llvm-svn: 303362
2017-05-18 17:24:10 +00:00
Craig Topper 8df66c602a [KnownBits] Add bit counting methods to KnownBits struct and use them where possible
This patch adds min/max population count, leading/trailing zero/one bit counting methods.

The min methods return answers based on bits that are known without considering unknown bits. The max methods give answers taking into account the largest count that unknown bits could give.

Differential Revision: https://reviews.llvm.org/D32931

llvm-svn: 302925
2017-05-12 17:20:30 +00:00
Daniel Berlin 4d0fe64ae3 Kill off the old SimplifyInstruction API by converting remaining users.
llvm-svn: 301673
2017-04-28 19:55:38 +00:00
Craig Topper b45eabcf82 [ValueTracking] Introduce a KnownBits struct to wrap the two APInts for computeKnownBits
This patch introduces a new KnownBits struct that wraps the two APInt used by computeKnownBits. This allows us to treat them as more of a unit.

Initially I've just altered the signatures of computeKnownBits and InstCombine's simplifyDemandedBits to pass a KnownBits reference instead of two separate APInt references. I'll do similar to the SelectionDAG version of computeKnownBits/simplifyDemandedBits as a separate patch.

I've added a constructor that allows initializing both APInts to the same bit width with a starting value of 0. This reduces the repeated pattern of initializing both APInts. Once place default constructed the APInts so I added a default constructor for those cases.

Going forward I would like to add more methods that will work on the pairs. For example trunc, zext, and sext occur on both APInts together in several places. We should probably add a clear method that can be used to clear both pieces. Maybe a method to check for conflicting information. A method to return (Zero|One) so we don't write it out everywhere. Maybe a method for (Zero|One).isAllOnesValue() to determine if all bits are known. I'm sure there are many other methods we can come up with.

Differential Revision: https://reviews.llvm.org/D32376

llvm-svn: 301432
2017-04-26 16:39:58 +00:00