Commit Graph

43 Commits

Author SHA1 Message Date
Peter Collingbourne 9a3f97977f IR: Fix a race condition in type id clients of ModuleSummaryIndex.
Add a const version of the getTypeIdSummary accessor that avoids
mutating the TypeIdMap.

Differential Revision: https://reviews.llvm.org/D31226

llvm-svn: 298531
2017-03-22 18:04:39 +00:00
Peter Collingbourne 14dcf02fcb WholeProgramDevirt: Implement export/import support for VCP.
Differential Revision: https://reviews.llvm.org/D30017

llvm-svn: 297503
2017-03-10 20:13:58 +00:00
Peter Collingbourne 59675ba0f8 WholeProgramDevirt: Implement export/import support for unique ret val opt.
Differential Revision: https://reviews.llvm.org/D29917

llvm-svn: 297502
2017-03-10 20:09:11 +00:00
George Rimar 5d8aea1009 WholeProgramDevirt: Fixed compilation error under MSVS2015.
It was introduced in:

r296945
WholeProgramDevirt: Implement exporting for single-impl devirtualization.
---------------------
r296939
WholeProgramDevirt: Add any unsuccessful llvm.type.checked.load devirtualizations to the list of llvm.type.test users.
---------------------

Microsoft Visual Studio Community 2015
Version 14.0.23107.0 D14REL
Does not compile that code without additional brackets, showing multiple error like below:

WholeProgramDevirt.cpp(1216): error C2958: the left bracket '[' found at 'c:\access_softek\llvm\lib\transforms\ipo\wholeprogramdevirt.cpp(1216)' was not matched correctly
WholeProgramDevirt.cpp(1216): error C2143: syntax error: missing ']' before '}'
WholeProgramDevirt.cpp(1216): error C2143: syntax error: missing ';' before '}'
WholeProgramDevirt.cpp(1216): error C2059: syntax error: ']'

llvm-svn: 297451
2017-03-10 10:31:56 +00:00
Peter Collingbourne 0152c8156b WholeProgramDevirt: Implement importing for uniform ret val opt.
Differential Revision: https://reviews.llvm.org/D29854

llvm-svn: 297350
2017-03-09 01:11:15 +00:00
Peter Collingbourne 6d284fab20 WholeProgramDevirt: Implement importing for single-impl devirtualization.
Differential Revision: https://reviews.llvm.org/D29844

llvm-svn: 297333
2017-03-09 00:21:25 +00:00
Peter Collingbourne f0bb90b126 Fix build.
llvm-svn: 296949
2017-03-04 01:38:05 +00:00
Peter Collingbourne 77a8d563a3 WholeProgramDevirt: Implement exporting for uniform ret val opt.
Differential Revision: https://reviews.llvm.org/D29846

llvm-svn: 296948
2017-03-04 01:34:53 +00:00
Peter Collingbourne 2325bb34c1 WholeProgramDevirt: Implement exporting for single-impl devirtualization.
Differential Revision: https://reviews.llvm.org/D29811

llvm-svn: 296945
2017-03-04 01:31:01 +00:00
Peter Collingbourne b406baaeef WholeProgramDevirt: Add any unsuccessful llvm.type.checked.load devirtualizations to the list of llvm.type.test users.
Any unsuccessful llvm.type.checked.load devirtualizations will be translated
into uses of llvm.type.test, so we need to add the resulting llvm.type.test
intrinsics to the function summaries so that the LowerTypeTests pass will
export them.

Differential Revision: https://reviews.llvm.org/D29808

llvm-svn: 296939
2017-03-04 01:23:30 +00:00
Adam Nemet de53bfb94d [OptDiag] Hide legacy remark ctors
These are only used when emitting remarks without ORE directly using the free
functions emitOptimizationRemark*.

llvm-svn: 296037
2017-02-23 23:11:11 +00:00
Justin Bogner 7bc978b543 OptDiag: Allow constructing DiagnosticLocation from DISubprograms
This avoids creating a DILocation just to represent a line number,
since creating Metadata is expensive. Creating a DiagnosticLocation
directly is much cheaper.

llvm-svn: 295531
2017-02-18 02:00:27 +00:00
Peter Collingbourne 184773d81f WholeProgramDevirt: For VCP use a 32-bit ConstantInt for the byte offset.
A future change will cause this byte offset to be inttoptr'd and then exported
via an absolute symbol. On the importing end we will expect the symbol to be
in range [0,2^32) so that it will fit into a 32-bit relocation. The problem
is that on 64-bit architectures if the offset is negative it will not be in
the correct range once we inttoptr it.

This change causes us to use a 32-bit integer so that it can be inttoptr'd
(which zero extends) into the correct range.

Differential Revision: https://reviews.llvm.org/D30016

llvm-svn: 295487
2017-02-17 19:43:45 +00:00
Peter Collingbourne 37317f1207 WholeProgramDevirt: Examine the function body when deciding whether functions are readnone.
The goal is to get an analysis result even for de-refineable functions.

Differential Revision: https://reviews.llvm.org/D29803

llvm-svn: 295472
2017-02-17 18:17:04 +00:00
Peter Collingbourne 50cbd7cc90 Re-apply r295110 and r295144 with a fix for the ASan issue.
llvm-svn: 295241
2017-02-15 21:56:51 +00:00
Daniel Jasper eef9b03395 Revert r295110 and r295144.
This fails under ASAN:
http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-bootstrap/builds/798/steps/check-llvm%20asan/logs/stdio

llvm-svn: 295162
2017-02-15 09:56:08 +00:00
Peter Collingbourne e2367415b6 WholeProgramDevirt: Separate the code that applies optzns from the code that decides whether to apply them. NFCI.
The idea is that the apply* functions will also be called when importing
devirt optimizations.

Differential Revision: https://reviews.llvm.org/D29745

llvm-svn: 295144
2017-02-15 02:13:08 +00:00
Peter Collingbourne 534c0175b6 WholeProgramDevirt: Change internal vcall data structures to match summary.
Group calls into constant and non-constant arguments up front, and use uint64_t
instead of ConstantInt to represent constant arguments. The goal is to allow
the information from the summary to fit naturally into this data structure in
a future change (specifically, it will be added to CallSiteInfo).

This has two side effects:
- We disallow VCP for constant integer arguments of width >64 bits.
- We remove the restriction that the bitwidth of a vcall's argument and return
  types must match those of the vfunc definitions.
I don't expect either of these to matter in practice. The first case is
uncommon, and the second one will lead to UB (so we can do anything we like).

Differential Revision: https://reviews.llvm.org/D29744

llvm-svn: 295110
2017-02-14 22:12:23 +00:00
Peter Collingbourne 2b33f65317 IR: Type ID summary extensions for WPD; thread summary into WPD pass.
Make the whole thing testable by adding YAML I/O support for the WPD
summary information and adding some negative tests that exercise the
YAML support.

Differential Revision: https://reviews.llvm.org/D29782

llvm-svn: 294981
2017-02-13 19:26:18 +00:00
Peter Collingbourne 17febdbb25 WholeProgramDevirt: Check that VCP candidate functions are defined before evaluating them.
This was crashing before.

llvm-svn: 294666
2017-02-09 23:46:26 +00:00
Peter Collingbourne 8786754cc3 WholeProgramDevirt: Teach the pass to handle structs of arrays.
This will become necessary in some cases once D22296 lands.

llvm-svn: 289165
2016-12-09 01:10:11 +00:00
Peter Collingbourne 7a1e5bbe4e Make WholeProgramDevirt understand ConstStruct vtables.
Based on a patch by LemonBoy!

Differential Revision: https://reviews.llvm.org/D26581

llvm-svn: 289162
2016-12-09 00:33:27 +00:00
Adam Nemet 04758ba385 Shorten DiagnosticInfoOptimizationRemark* to OptimizationRemark*. NFC
With the new streaming interface, these class names need to be typed a
lot and it's way too looong.

llvm-svn: 282544
2016-09-27 22:19:23 +00:00
Ivan Krasin 89439a7939 WholeProgramDevirt: initialize WasDevirt in all constructors.
Summary: This is a follow up to r278389 and r278442.

Differential Revision: https://reviews.llvm.org/D23438

llvm-svn: 278455
2016-08-12 01:40:10 +00:00
Ivan Krasin f3403fd2c8 WholeProgramDevirt: generate more detailed and accurate remarks.
Summary:
Keep track of all methods for which we have devirtualized at least
one call and then print them sorted alphabetically. That allows to
avoid duplicates and also makes the order deterministic.

Add optimization names into the remarks, so that it's easier to
understand how has each method been devirtualized.

Fix a bug when wrong methods could have been reported for
tryVirtualConstProp.

Reviewers: kcc, mehdi_amini

Differential Revision: https://reviews.llvm.org/D23297

llvm-svn: 278389
2016-08-11 19:09:02 +00:00
Eugene Zelenko cdc7161281 Fix some Clang-tidy modernize and Include What You Use warnings.
Differential revision: https://reviews.llvm.org/D23291

llvm-svn: 278364
2016-08-11 17:20:18 +00:00
Ivan Krasin b05e06e4fd WholeProgramDevirt: print remarks with devirtualized method names.
Summary:
Chrome on Linux uses WholeProgramDevirt for speed ups, and it's
important to detect regressions on both sides: the toolchain,
if fewer methods get devirtualized after an update, and Chrome,
if an innocently looking change caused many hot methods become
virtual again.

The need to track devirtualized methods is not Chrome-specific,
but it's probably the only user of the pass at this time.

Reviewers: kcc

Differential Revision: https://reviews.llvm.org/D23219

llvm-svn: 277856
2016-08-05 19:45:16 +00:00
Ivan Krasin 5474645dc8 Print remarks from WholeProgramDevirt pass for each call site.
Summary:
It's useful to have some visibility about which call sites are devirtualized,
especially for debug purposes. Another use case is a regression test on the
application side (like, Chromium).

Reviewers: pcc

Differential Revision: http://reviews.llvm.org/D22252

llvm-svn: 275145
2016-07-12 02:38:37 +00:00
Peter Collingbourne 0312f614b1 IR: Introduce llvm.type.checked.load intrinsic.
This intrinsic safely loads a function pointer from a virtual table pointer
using type metadata. This intrinsic is used to implement control flow integrity
in conjunction with virtual call optimization. The virtual call optimization
pass will optimize away llvm.type.checked.load intrinsics associated with
devirtualized calls, thereby removing the type check in cases where it is
not needed to enforce the control flow integrity constraint.

This patch also introduces the capability to copy type metadata between
global variables, and teaches the virtual call optimization pass to do so.

Differential Revision: http://reviews.llvm.org/D21121

llvm-svn: 273756
2016-06-25 00:23:04 +00:00
Peter Collingbourne 7efd750607 IR: New representation for CFI and virtual call optimization pass metadata.
The bitset metadata currently used in LLVM has a few problems:

1. It has the wrong name. The name "bitset" refers to an implementation
   detail of one use of the metadata (i.e. its original use case, CFI).
   This makes it harder to understand, as the name makes no sense in the
   context of virtual call optimization.

2. It is represented using a global named metadata node, rather than
   being directly associated with a global. This makes it harder to
   manipulate the metadata when rebuilding global variables, summarise it
   as part of ThinLTO and drop unused metadata when associated globals are
   dropped. For this reason, CFI does not currently work correctly when
   both CFI and vcall opt are enabled, as vcall opt needs to rebuild vtable
   globals, and fails to associate metadata with the rebuilt globals. As I
   understand it, the same problem could also affect ASan, which rebuilds
   globals with a red zone.

This patch solves both of those problems in the following way:

1. Rename the metadata to "type metadata". This new name reflects how
   the metadata is currently being used (i.e. to represent type information
   for CFI and vtable opt). The new name is reflected in the name for the
   associated intrinsic (llvm.type.test) and pass (LowerTypeTests).

2. Attach metadata directly to the globals that it pertains to, rather
   than using the "llvm.bitsets" global metadata node as we are doing now.
   This is done using the newly introduced capability to attach
   metadata to global variables (r271348 and r271358).

See also: http://lists.llvm.org/pipermail/llvm-dev/2016-June/100462.html

Differential Revision: http://reviews.llvm.org/D21053

llvm-svn: 273729
2016-06-24 21:21:32 +00:00
Chandler Carruth 164a2aa6f4 [PM] Remove support for omitting the AnalysisManager argument to new
pass manager passes' `run` methods.

This removes a bunch of SFINAE goop from the pass manager and just
requires pass authors to accept `AnalysisManager<IRUnitT> &` as a dead
argument. This is a small price to pay for the simplicity of the system
as a whole, despite the noise that changing it causes at this stage.

This will also helpfull allow us to make the signature of the run
methods much more flexible for different kinds af passes to support
things like intelligently updating the pass's progression over IR units.

While this touches many, many, files, the changes are really boring.
Mostly made with the help of my trusty perl one liners.

Thanks to Sean and Hal for bouncing ideas for this with me in IRC.

llvm-svn: 272978
2016-06-17 00:11:01 +00:00
Davide Italiano d737dd2ec6 [PM] Port WholeProgramDevirt to the new pass manager.
llvm-svn: 272721
2016-06-14 21:44:19 +00:00
Peter Collingbourne ccdc225c27 Re-apply r269081 and r269082 with a fix for MSVC.
llvm-svn: 269094
2016-05-10 18:07:21 +00:00
Peter Collingbourne 4d41cb6cc6 Revert r269081 and r269082 while I try to find the right incantation to fix MSVC build.
llvm-svn: 269091
2016-05-10 17:54:43 +00:00
Peter Collingbourne 0df2b085bc WholeProgramDevirt: Move logic for finding devirtualizable call sites to Analysis.
The plan is to eventually make this logic simpler, however I expect it to
be a little tricky for the foreseeable future (at least until we're rid of
pointee types), so move it here so that it can be reused to build a summary
index for devirtualization.

Differential Revision: http://reviews.llvm.org/D20005

llvm-svn: 269081
2016-05-10 17:34:21 +00:00
Andrew Kaylor aa641a5171 Re-commit optimization bisect support (r267022) without new pass manager 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
2016-04-22 22:06:11 +00:00
Vedant Kumar 6013f45f92 Revert "Initial implementation of optimization bisect support."
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
2016-04-22 06:51:37 +00:00
Andrew Kaylor f0f279291c Initial implementation of optimization bisect support.
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
2016-04-21 17:58:54 +00:00
Mehdi Amini b550cb1750 [NFC] Header cleanup
Removed some unused headers, replaced some headers with forward class declarations.

Found using simple scripts like this one:
clear && ack --cpp -l '#include "llvm/ADT/IndexedMap.h"' | xargs grep -L 'IndexedMap[<]' | xargs grep -n --color=auto 'IndexedMap'

Patch by Eugene Kosov <claprix@yandex.ru>

Differential Revision: http://reviews.llvm.org/D19219

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 266595
2016-04-18 09:17:29 +00:00
Aaron Ballman ef0fe1eed8 Silencing warnings from MSVC 2015 Update 2. All of these changes silence "C4334 '<<': result of 32-bit shift implicitly converted to 64 bits (was 64-bit shift intended?)". NFC.
llvm-svn: 264929
2016-03-30 21:30:00 +00:00
Peter Collingbourne 3866cc5f69 Fix evaluation order. Spotted by Alexander Riccio!
llvm-svn: 262907
2016-03-08 03:50:36 +00:00
Peter Collingbourne 9b656527f1 Fix GCC build.
llvm-svn: 260317
2016-02-09 23:01:38 +00:00
Peter Collingbourne df49d1bbb2 WholeProgramDevirt: introduce.
This pass implements whole program optimization of virtual calls in cases
where we know (via bitset information) that the list of callees is fixed. This
includes the following:

- Single implementation devirtualization: if a virtual call has a single
  possible callee, replace all calls with a direct call to that callee.

- Virtual constant propagation: if the virtual function's return type is an
  integer <=64 bits and all possible callees are readnone, for each class and
  each list of constant arguments: evaluate the function, store the return
  value alongside the virtual table, and rewrite each virtual call as a load
  from the virtual table.

- Uniform return value optimization: if the conditions for virtual constant
  propagation hold and each function returns the same constant value, replace
  each virtual call with that constant.

- Unique return value optimization for i1 return values: if the conditions
  for virtual constant propagation hold and a single vtable's function
  returns 0, or a single vtable's function returns 1, replace each virtual
  call with a comparison of the vptr against that vtable's address.

Differential Revision: http://reviews.llvm.org/D16795

llvm-svn: 260312
2016-02-09 22:50:34 +00:00