Commit Graph

131 Commits

Author SHA1 Message Date
Sidharth Baveja b7cfa6ca92 [Loop Peeling] Separate the Loop Peeling Utilities from the Loop Unrolling Utilities
Summary: This patch separates the Loop Peeling Utilities from Loop Unrolling.
The reason for this change is that Loop Peeling is no longer only being used by
loop unrolling; Patch D82927 introduces loop peeling with fusion, such that
loops can be modified to have to same trip count, making them legal to be
peeled.

Reviewed By: Meinersbur

Differential Revision: https://reviews.llvm.org/D83056
2020-07-31 18:31:58 +00:00
Florian Hahn e1270b16c9 [Matrix] Add TileInfo abstraction for tiled matrix code-gen.
This patch adds a TileInfo abstraction and utilities to
create a 3-level loop nest for tiling.

Reviewers: anemet

Reviewed By: anemet

Differential Revision: https://reviews.llvm.org/D77550
2020-07-20 18:49:08 +01:00
Michal Paszkowski 335de55fa3 Revert "Added a new IRCanonicalizer pass."
This reverts commit 14d358537f.
2020-05-23 13:51:43 +02:00
Michal Paszkowski 14d358537f Added a new IRCanonicalizer pass.
Summary:
Added a new IRCanonicalizer pass which aims to transform LLVM modules into
a canonical form by reordering and renaming instructions while preserving the
same semantics. The canonicalizer makes it easier to spot semantic differences
when diffing two modules which have undergone different passes.

Presentation: https://www.youtube.com/watch?v=c9WMijSOEUg

Reviewed by: plotfi

Differential Revision: https://reviews.llvm.org/D66029
2020-05-23 12:45:53 +02:00
Juneyoung Lee d9a4a24413 Add CanonicalizeFreezeInLoops pass
Summary:
If an induction variable is frozen and used, SCEV yields imprecise result
because it doesn't say anything about frozen variables.

Due to this reason, performance degradation happened after
https://reviews.llvm.org/D76483 is merged, causing
SCEV yield imprecise result and preventing LSR to optimize a loop.

The suggested solution here is to add a pass which canonicalizes frozen variables
inside a loop. To be specific, it pushes freezes out of the loop by freezing
the initial value and step values instead & dropping nsw/nuw flags from instructions used by freeze.
This solution was also mentioned at https://reviews.llvm.org/D70623 .

Reviewers: spatel, efriedma, lebedev.ri, fhahn, jdoerfert

Reviewed By: fhahn

Subscribers: nikic, mgorny, hiraditya, javed.absar, llvm-commits, sanwou01, nlopes

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D77523
2020-05-21 09:29:29 +09:00
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
Sriraman Tallam 365b60fc93 New pass to make internal linkage symbol names unique.
With clang option -funique-internal-linkage-symbols, symbols with
internal linkage get names with the module hash appended.

Differential Revision: https://reviews.llvm.org/D78243
2020-04-20 15:05:22 -07:00
Sameer Sahasrabuddhe 8c11bc0cd0 Introduce fix-irreducible pass
An irreducible SCC is one which has multiple "header" blocks, i.e., blocks
with control-flow edges incident from outside the SCC. This pass converts an
irreducible SCC into a natural loop by introducing a single new header
block and redirecting all the edges on the original headers to this
new block.

This is a useful workaround for a limitation in the structurizer
which, which produces incorrect control flow in the presence of
irreducible regions. The AMDGPU backend provides an option to
enable this pass before the structurizer, which may eventually be
enabled by default.

Reviewed By: nhaehnle

Differential Revision: https://reviews.llvm.org/D77198

This restores commit 2ada8e2525.

Originally reverted with commit 44e09b59b8.
2020-04-15 15:05:51 +05:30
Sameer Sahasrabuddhe 44e09b59b8 Revert "Introduce fix-irreducible pass"
This reverts commit 2ada8e2525.

Buildbots produced compilation errors which I was not able to quickly
reproduce locally. Need more time to investigate.
2020-04-15 12:19:50 +05:30
Sameer Sahasrabuddhe 2ada8e2525 Introduce fix-irreducible pass
An irreducible SCC is one which has multiple "header" blocks, i.e., blocks
with control-flow edges incident from outside the SCC. This pass converts an
irreducible SCC into a natural loop by introducing a single new header
block and redirecting all the edges on the original headers to this
new block.

This is a useful workaround for a limitation in the structurizer
which, which produces incorrect control flow in the presence of
irreducible regions. The AMDGPU backend provides an option to
enable this pass before the structurizer, which may eventually be
enabled by default.

Reviewed By: nhaehnle

Differential Revision: https://reviews.llvm.org/D77198
2020-04-15 11:29:19 +05:30
Tyker c00cb76274 [NFC] Split Knowledge retention and place it more appropriatly
Summary:
Splitting Knowledge retention into Queries in Analysis and Builder into Transform/Utils
allows Queries and Transform/Utils to use Analysis.

Reviewers: jdoerfert, sstefan1

Reviewed By: jdoerfert

Subscribers: mgorny, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D77171
2020-04-02 15:01:41 +02:00
Sameer Sahasrabuddhe 3cbbded68c Introduce unify-loop-exits pass.
For each natural loop with multiple exit blocks, this pass creates a
new block N such that all exiting blocks now branch to N, and then
control flow is redistributed to all the original exit blocks.

The bulk of the tranformation is a new function introduced in
BasicBlockUtils that an redirect control flow from a set of incoming
blocks to a set of outgoing blocks via a common "hub".

This is a useful workaround for a limitation in the structurizer which
incorrectly orders blocks when processing a nest of loops. This pass
bypasses that issue by ensuring that each natural loop is recognized
as a separate region. Since the structurizer is a region pass, it no
longer sees a nest of loops in a single region, and instead processes
each "level" in the nesting as a separate region.

The AMDGPU backend provides a new option to enable this pass before
the structurizer, which may eventually be enabled by default.

Reviewers: madhur13490, arsenm, nhaehnle

Reviewed By: nhaehnle

Differential Revision: https://reviews.llvm.org/D75865
2020-03-30 13:23:56 -04:00
Tyker a4cde9ad7b Fixed [AssumeBundles] Move to IR so it can be used by Analysis
This is a recommit of 57c964aaa7
after fixing modules build.
2020-03-10 18:02:39 +01:00
Jonas Devlieghere 882f589e20 Revert "[AssumeBundles] Move to IR so it can be used by Analysis"
This breaks the modules build:

http://green.lab.llvm.org/green/job/clang-stage2-Rthinlto/
http://green.lab.llvm.org/green/view/LLDB/job/lldb-cmake/

This reverts commit 57c964aaa7.
2020-03-09 09:02:47 -07:00
Tyker 57c964aaa7 [AssumeBundles] Move to IR so it can be used by Analysis
Summary:
Assume bundles need to be usable by Analysis and Transforms/Utils isn't.
so this commit moves utilities to deal with asusme bundles to IR.

Reviewers: jdoerfert

Reviewed By: jdoerfert

Subscribers: mgorny, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D75618
2020-03-08 12:21:50 +01:00
Johannes Doerfert 72277ecd62 Introduce a CallGraph updater helper class
The CallGraphUpdater is a helper that simplifies the process of updating
the call graph, both old and new style, while running an CGSCC pass.

The uses are contained in different commits, e.g. D70767.

More functionality is added as we need it.

Reviewed By: modocache, hfinkel

Differential Revision: https://reviews.llvm.org/D70927
2020-02-08 14:16:48 -06:00
Tyker a7bbe45a3e Build assume from call
Fix attempt

this is part of the implementation of http://lists.llvm.org/pipermail/llvm-dev/2019-December/137632.html

this patch gives the basis of building an assume to preserve all information from an instruction and add support for building an assume that preserve the information from a call.
2020-02-02 19:43:36 +01:00
Tyker 7cb5d96fbe Revert "[WIP] Build assume from call"
casued buildbot failure

This reverts commit 8ebe001553.
2020-02-02 18:35:19 +01:00
Tyker 8ebe001553 [WIP] Build assume from call
Summary:
this is part of the implementation of http://lists.llvm.org/pipermail/llvm-dev/2019-December/137632.html

this patch gives the basis of building an assume to preserve all information from an instruction and add support for building an assume that preserve the information from a call.

Reviewers: jdoerfert

Reviewed By: jdoerfert

Subscribers: mgrang, fhahn, mgorny, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D72475
2020-02-02 18:15:50 +01:00
Tyker c2d0336208 Revert "[WIP] Build assume from call"
caused build bot failure

This reverts commit 780d2c532f.
2020-02-02 18:09:06 +01:00
Tyker 780d2c532f [WIP] Build assume from call
Summary:
this is part of the implementation of http://lists.llvm.org/pipermail/llvm-dev/2019-December/137632.html

this patch gives the basis of building an assume to preserve all information from an instruction and add support for building an assume that preserve the information from a call.

Reviewers: jdoerfert

Reviewed By: jdoerfert

Subscribers: mgrang, fhahn, mgorny, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D72475
2020-02-02 17:54:31 +01:00
Tyker ad8ffc5010 Revert "[WIP] Build assume from call"
This reverts commit 355e4bfd78.
2020-02-02 17:49:23 +01:00
Tyker 355e4bfd78 [WIP] Build assume from call
Summary:
this is part of the implementation of http://lists.llvm.org/pipermail/llvm-dev/2019-December/137632.html

this patch gives the basis of building an assume to preserve all information from an instruction and add support for building an assume that preserve the information from a call.

Reviewers: jdoerfert

Reviewed By: jdoerfert

Subscribers: mgrang, fhahn, mgorny, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D72475
2020-02-02 17:17:46 +01:00
Tyker 0adda3df92 Revert "[WIP] Build assume from call"
This reverts commit 2ff5602cb5.
2020-02-02 15:05:33 +01:00
Tyker 2ff5602cb5 [WIP] Build assume from call
Summary:
this is part of the implementation of http://lists.llvm.org/pipermail/llvm-dev/2019-December/137632.html

this patch gives the basis of building an assume to preserve all information from an instruction and add support for building an assume that preserve the information from a call.

Reviewers: jdoerfert

Reviewed By: jdoerfert

Subscribers: mgrang, fhahn, mgorny, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D72475
2020-02-02 14:50:31 +01:00
Sameer Sahasrabuddhe ed181efa17 [HIP][AMDGPU] expand printf when compiling HIP to AMDGPU
Summary:
This change implements the expansion in two parts:
- Add a utility function emitAMDGPUPrintfCall() in LLVM.
- Invoke the above function from Clang CodeGen, when processing a HIP
  program for the AMDGPU target.

The printf expansion has undefined behaviour if the format string is
not a compile-time constant. As a sufficient condition, the HIP
ToolChain now emits -Werror=format-nonliteral.

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D71365
2020-01-16 15:15:38 +05:30
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
Tsang Whitney W.H ae8a8c2db6 [CodeMoverUtils] Added an API to check if an instruction can be safely
moved before another instruction.
Summary:Added an API to check if an instruction can be safely moved
before another instruction. In future PRs, we will like to add support
of moving instructions between blocks that are not control flow
equivalent, and add other APIs to enhance usability, e.g. moving basic
blocks, moving list of instructions...
Loop Fusion will be its first user. When there is intervening code in
between two loops, fusion is currently unable to fuse them. Loop Fusion
can use this utility to check if the intervening code can be safely
moved before or after the two loops, and move them, then it can
successfully fuse them.
Reviewer:kbarton,jdoerfert,Meinersbur,bmahjour,etiotto
Reviewed By:bmahjour
Subscribers:mgorny,hiraditya,llvm-commits
Tag:LLVM
Differential Revision:https://reviews.llvm.org/D70049
2019-11-22 21:29:08 +00:00
Tom Stellard ab411801b8 [cmake] Explicitly mark libraries defined in lib/ as "Component Libraries"
Summary:
Most libraries are defined in the lib/ directory but there are also a
few libraries defined in tools/ e.g. libLLVM, libLTO.  I'm defining
"Component Libraries" as libraries defined in lib/ that may be included in
libLLVM.so.  Explicitly marking the libraries in lib/ as component
libraries allows us to remove some fragile checks that attempt to
differentiate between lib/ libraries and tools/ libraires:

1. In tools/llvm-shlib, because
llvm_map_components_to_libnames(LIB_NAMES "all") returned a list of
all libraries defined in the whole project, there was custom code
needed to filter out libraries defined in tools/, none of which should
be included in libLLVM.so.  This code assumed that any library
defined as static was from lib/ and everything else should be
excluded.

With this change, llvm_map_components_to_libnames(LIB_NAMES, "all")
only returns libraries that have been added to the LLVM_COMPONENT_LIBS
global cmake property, so this custom filtering logic can be removed.
Doing this also fixes the build with BUILD_SHARED_LIBS=ON
and LLVM_BUILD_LLVM_DYLIB=ON.

2. There was some code in llvm_add_library that assumed that
libraries defined in lib/ would not have LLVM_LINK_COMPONENTS or
ARG_LINK_COMPONENTS set.  This is only true because libraries
defined lib lib/ use LLVMBuild.txt and don't set these values.
This code has been fixed now to check if the library has been
explicitly marked as a component library, which should now make it
easier to remove LLVMBuild at some point in the future.

I have tested this patch on Windows, MacOS and Linux with release builds
and the following combinations of CMake options:

- "" (No options)
- -DLLVM_BUILD_LLVM_DYLIB=ON
- -DLLVM_LINK_LLVM_DYLIB=ON
- -DBUILD_SHARED_LIBS=ON
- -DBUILD_SHARED_LIBS=ON -DLLVM_BUILD_LLVM_DYLIB=ON
- -DBUILD_SHARED_LIBS=ON -DLLVM_LINK_LLVM_DYLIB=ON

Reviewers: beanz, smeenai, compnerd, phosek

Reviewed By: beanz

Subscribers: wuzish, jholewinski, arsenm, dschuff, jyknight, dylanmckay, sdardis, nemanjai, jvesely, nhaehnle, mgorny, mehdi_amini, sbc100, jgravelle-google, hiraditya, aheejin, fedor.sergeev, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, atanasyan, steven_wu, rogfer01, MartinMosbeck, brucehoult, the_o, dexonsmith, PkmX, jocewei, jsji, dang, Jim, lenary, s.egerton, pzheng, sameer.abuasal, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70179
2019-11-21 10:48:08 -08:00
Francesco Petrogalli d6de5f12d4 [SVFS] Inject TLI Mappings in VFABI attribute.
This patch introduces a function pass to inject the scalar-to-vector
mappings stored in the TargetLIbraryInfo (TLI) into the Vector
Function ABI (VFABI) variants attribute.

The test is testing the injection for three vector libraries supported
by the TLI (Accelerate, SVML, MASSV).

The pass does not change any of the analysis associated to the
function.

Differential Revision: https://reviews.llvm.org/D70107
2019-11-15 18:42:56 +00:00
Daniel Sanders 25ee861372 [debugify] Move the Debugify pass from tools/opt to lib/Transform/Utils
Summary:
I need to make use of this pass from a driver program that isn't opt.
Therefore this patch moves this pass into the LLVM library so that it is
available for use elsewhere.

There was one function I kept in tools/opt which is exportDebugifyStats()
this is because it's serializing the statistics into a human readable
format and this seemed more in keeping with opt than a library function

Reviewers: vsk, aprantl

Subscribers: mgorny, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69926
2019-11-07 14:41:54 -08:00
Petr Hosek 7bdad08429 Reland "clang-misexpect: Profile Guided Validation of Performance Annotations in LLVM"
This patch contains the basic functionality for reporting potentially
incorrect usage of __builtin_expect() by comparing the developer's
annotation against a collected PGO profile. A more detailed proposal and
discussion appears on the CFE-dev mailing list
(http://lists.llvm.org/pipermail/cfe-dev/2019-July/062971.html) and a
prototype of the initial frontend changes appear here in D65300

We revised the work in D65300 by moving the misexpect check into the
LLVM backend, and adding support for IR and sampling based profiles, in
addition to frontend instrumentation.

We add new misexpect metadata tags to those instructions directly
influenced by the llvm.expect intrinsic (branch, switch, and select)
when lowering the intrinsics. The misexpect metadata contains
information about the expected target of the intrinsic so that we can
check against the correct PGO counter when emitting diagnostics, and the
compiler's values for the LikelyBranchWeight and UnlikelyBranchWeight.
We use these branch weight values to determine when to emit the
diagnostic to the user.

A future patch should address the comment at the top of
LowerExpectIntrisic.cpp to hoist the LikelyBranchWeight and
UnlikelyBranchWeight values into a shared space that can be accessed
outside of the LowerExpectIntrinsic pass. Once that is done, the
misexpect metadata can be updated to be smaller.

In the long term, it is possible to reconstruct portions of the
misexpect metadata from the existing profile data. However, we have
avoided this to keep the code simple, and because some kind of metadata
tag will be required to identify which branch/switch/select instructions
are influenced by the use of llvm.expect

Patch By: paulkirth
Differential Revision: https://reviews.llvm.org/D66324

llvm-svn: 371635
2019-09-11 16:19:50 +00:00
Dmitri Gribenko 57256af307 Revert "clang-misexpect: Profile Guided Validation of Performance Annotations in LLVM"
This reverts commit r371584. It introduced a dependency from compiler-rt
to llvm/include/ADT, which is problematic for multiple reasons.

One is that it is a novel dependency edge, which needs cross-compliation
machinery for llvm/include/ADT (yes, it is true that right now
compiler-rt included only header-only libraries, however, if we allow
compiler-rt to depend on anything from ADT, other libraries will
eventually get used).

Secondly, depending on ADT from compiler-rt exposes ADT symbols from
compiler-rt, which would cause ODR violations when Clang is built with
the profile library.

llvm-svn: 371598
2019-09-11 09:16:17 +00:00
Petr Hosek 394a8ed8f1 clang-misexpect: Profile Guided Validation of Performance Annotations in LLVM
This patch contains the basic functionality for reporting potentially
incorrect usage of __builtin_expect() by comparing the developer's
annotation against a collected PGO profile. A more detailed proposal and
discussion appears on the CFE-dev mailing list
(http://lists.llvm.org/pipermail/cfe-dev/2019-July/062971.html) and a
prototype of the initial frontend changes appear here in D65300

We revised the work in D65300 by moving the misexpect check into the
LLVM backend, and adding support for IR and sampling based profiles, in
addition to frontend instrumentation.

We add new misexpect metadata tags to those instructions directly
influenced by the llvm.expect intrinsic (branch, switch, and select)
when lowering the intrinsics. The misexpect metadata contains
information about the expected target of the intrinsic so that we can
check against the correct PGO counter when emitting diagnostics, and the
compiler's values for the LikelyBranchWeight and UnlikelyBranchWeight.
We use these branch weight values to determine when to emit the
diagnostic to the user.

A future patch should address the comment at the top of
LowerExpectIntrisic.cpp to hoist the LikelyBranchWeight and
UnlikelyBranchWeight values into a shared space that can be accessed
outside of the LowerExpectIntrinsic pass. Once that is done, the
misexpect metadata can be updated to be smaller.

In the long term, it is possible to reconstruct portions of the
misexpect metadata from the existing profile data. However, we have
avoided this to keep the code simple, and because some kind of metadata
tag will be required to identify which branch/switch/select instructions
are influenced by the use of llvm.expect

Patch By: paulkirth
Differential Revision: https://reviews.llvm.org/D66324

llvm-svn: 371584
2019-09-11 01:09:16 +00:00
Petr Hosek 7d1757aba8 Revert "clang-misexpect: Profile Guided Validation of Performance Annotations in LLVM"
This reverts commit r371484: this broke sanitizer-x86_64-linux-fast bot.

llvm-svn: 371488
2019-09-10 06:25:13 +00:00
Petr Hosek a10802fd73 clang-misexpect: Profile Guided Validation of Performance Annotations in LLVM
This patch contains the basic functionality for reporting potentially
incorrect usage of __builtin_expect() by comparing the developer's
annotation against a collected PGO profile. A more detailed proposal and
discussion appears on the CFE-dev mailing list
(http://lists.llvm.org/pipermail/cfe-dev/2019-July/062971.html) and a
prototype of the initial frontend changes appear here in D65300

We revised the work in D65300 by moving the misexpect check into the
LLVM backend, and adding support for IR and sampling based profiles, in
addition to frontend instrumentation.

We add new misexpect metadata tags to those instructions directly
influenced by the llvm.expect intrinsic (branch, switch, and select)
when lowering the intrinsics. The misexpect metadata contains
information about the expected target of the intrinsic so that we can
check against the correct PGO counter when emitting diagnostics, and the
compiler's values for the LikelyBranchWeight and UnlikelyBranchWeight.
We use these branch weight values to determine when to emit the
diagnostic to the user.

A future patch should address the comment at the top of
LowerExpectIntrisic.cpp to hoist the LikelyBranchWeight and
UnlikelyBranchWeight values into a shared space that can be accessed
outside of the LowerExpectIntrinsic pass. Once that is done, the
misexpect metadata can be updated to be smaller.

In the long term, it is possible to reconstruct portions of the
misexpect metadata from the existing profile data. However, we have
avoided this to keep the code simple, and because some kind of metadata
tag will be required to identify which branch/switch/select instructions
are influenced by the use of llvm.expect

Patch By: paulkirth
Differential Revision: https://reviews.llvm.org/D66324

llvm-svn: 371484
2019-09-10 03:11:39 +00:00
Hiroshi Yamauchi 09e539fcae [PGO] Profile guided code size optimization.
Summary:
Enable some of the existing size optimizations for cold code under PGO.

A ~5% code size saving in big internal app under PGO.

The way it gets BFI/PSI is discussed in the RFC thread

http://lists.llvm.org/pipermail/llvm-dev/2019-March/130894.html 

Note it doesn't currently touch loop passes.

Reviewers: davidxl, eraman

Reviewed By: eraman

Subscribers: mgorny, javed.absar, smeenai, mehdi_amini, eraman, zzheng, steven_wu, dexonsmith, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D59514

llvm-svn: 358422
2019-04-15 16:49:00 +00:00
Teresa Johnson 853b962416 [ThinLTO] Handle chains of aliases
At -O0, globalopt is not run during the compile step, and we can have a
chain of an alias having an immediate aliasee of another alias. The
summaries are constructed assuming aliases in a canonical form
(flattened chains), and as a result only the base object but no
intermediate aliases were preserved.

Fix by adding a pass that canonicalize aliases, which ensures each
alias is a direct alias of the base object.

Reviewers: pcc, davidxl

Subscribers: mehdi_amini, inglorion, eraman, steven_wu, dexonsmith, arphaman, llvm-commits

Differential Revision: https://reviews.llvm.org/D54507

llvm-svn: 350423
2019-01-04 19:04:54 +00:00
Max Kazantsev d3a4cbe153 [NFC] Move OrderedInstructions and InstructionPrecedenceTracking to Analysis
These classes don't make any changes to IR and have no reason to be in
Transform/Utils. This patch moves them to Analysis folder. This will allow
us reusing these classes in some analyzes, like MustExecute.

llvm-svn: 341015
2018-08-30 04:49:03 +00:00
Max Kazantsev 8b4ffe66d6 [NFC] Factor out guard utility methods into a separate file
This patch creates file GuardUtils which will contain logic for work with guards
that can be shared across different passes.

Differential Revision: https://reviews.llvm.org/D51151
Reviewed By: fedor.sergeev

llvm-svn: 340914
2018-08-29 10:51:59 +00:00
Max Kazantsev b5dd092051 [NFC] Split logic of ImplicitControlFlowTracking to allow generalization
We have a class `ImplicitControlFlowTracking` which allows us to keep track of
instructions that can abnormally exit and answer queries like "whether or not
there is side-exiting instruction above this instruction in its block".

We may want to have the similar tracking for other types of "special" instructions,
for example instructions that write memory.

This patch separates ImplicitControlFlowTracking into two classes, isolating all
general logic not related to implicit control flow into its parent class. We can
later make another child of this class to keep track of instructions that write
memory.

The motivation for that is that we want to make these checks efficiently in the
patch https://reviews.llvm.org/D50891.

NOTE: The naming of the parent class is not super cool, but the other options we
have are hardly better. Please feel free to rename it as NFC if you think you've
found a more informative name for it.

Differential Revision: https://reviews.llvm.org/D50954
Reviewed By: fedor.sergeev

llvm-svn: 340728
2018-08-27 09:43:16 +00:00
Max Kazantsev 640cb00365 [NFC] Factor out implicit control flow logic from GVN
Logic for tracking implicit control flow instructions was added to GVN to
perform PRE optimizations correctly. It appears that GVN is not the only
optimization that sometimes does PRE, so this logic is required in other
places (such as Jump Threading).

This is an NFC patch that encapsulates all ICF-related logic in a dedicated
utility class separated from GVN.

Differential Revision: https://reviews.llvm.org/D40293

llvm-svn: 339086
2018-08-07 01:47:20 +00:00
David Green 963401d2be [UnrollAndJam] New Unroll and Jam pass
This is a simple implementation of the unroll-and-jam classical loop
optimisation.

The basic idea is that we take an outer loop of the form:

  for i..
    ForeBlocks(i)
    for j..
      SubLoopBlocks(i, j)
    AftBlocks(i)

Instead of doing normal inner or outer unrolling, we unroll as follows:

  for i... i+=2
    ForeBlocks(i)
    ForeBlocks(i+1)
    for j..
      SubLoopBlocks(i, j)
      SubLoopBlocks(i+1, j)
    AftBlocks(i)
    AftBlocks(i+1)
  Remainder Loop

So we have unrolled the outer loop, then jammed the two inner loops into
one. This can lead to a simpler inner loop if memory accesses can be shared
between the now jammed loops.

To do this we have to prove that this is all safe, both for the memory
accesses (using dependence analysis) and that ForeBlocks(i+1) can move before
AftBlocks(i) and SubLoopBlocks(i, j).

Differential Revision: https://reviews.llvm.org/D41953

llvm-svn: 336062
2018-07-01 12:47:30 +00:00
Chandler Carruth 7c557f804d [instsimplify] Move the instsimplify pass to use more obvious file names
and diretory.

Also cleans up all the associated naming to be consistent and removes
the public access to the pass ID which was unused in LLVM.

Also runs clang-format over parts that changed, which generally cleans
up a bunch of formatting.

This is in preparation for doing some internal cleanups to the pass.

Differential Revision: https://reviews.llvm.org/D47352

llvm-svn: 336028
2018-06-29 23:36:03 +00:00
David Green aee7ad0cde Revert 333358 as it's failing on some builders.
I'm guessing the tests reply on the ARM backend being built.

llvm-svn: 333359
2018-05-27 12:54:33 +00:00
David Green 3034281b43 [UnrollAndJam] Add a new Unroll and Jam pass
This is a simple implementation of the unroll-and-jam classical loop
optimisation.

The basic idea is that we take an outer loop of the form:

for i..
  ForeBlocks(i)
  for j..
    SubLoopBlocks(i, j)
  AftBlocks(i)

Instead of doing normal inner or outer unrolling, we unroll as follows:

for i... i+=2
  ForeBlocks(i)
  ForeBlocks(i+1)
  for j..
    SubLoopBlocks(i, j)
    SubLoopBlocks(i+1, j)
  AftBlocks(i)
  AftBlocks(i+1)
Remainder

So we have unrolled the outer loop, then jammed the two inner loops into
one. This can lead to a simpler inner loop if memory accesses can be shared
between the now-jammed loops.

To do this we have to prove that this is all safe, both for the memory
accesses (using dependence analysis) and that ForeBlocks(i+1) can move before
AftBlocks(i) and SubLoopBlocks(i, j).

Differential Revision: https://reviews.llvm.org/D41953

llvm-svn: 333358
2018-05-27 12:11:21 +00:00
Michael Zolotukhin 52b064f3d3 [PR16756] Add SSAUpdaterBulk.
Summary:
SSAUpdater is a bottleneck in a number of passes, and one of the reasons
is that it performs a lot of unnecessary computations (DT/IDF) over and
over again. This patch adds a new SSAUpdaterBulk that uses existing DT
and avoids recomputing IDF when possible.

Reviewers: dberlin, davide, MatzeB

Subscribers: llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D44282

llvm-svn: 329643
2018-04-09 23:37:20 +00:00
David Green b0aa36f9c2 [LoopRotate] Restructuring LoopRotation.cpp to create Loop Rotation Pass with Loop Rotation Utility Interface
The existing LoopRotation.cpp is implemented as one of loop passes instead of
being a utility. The user cannot easily perform the loop rotation selectively
(or on demand) under different optimization level. For example, the loop
rotation is needed as part of the logic to convert a loop into a loop with
bottom test for a transformation. If the loop rotation is simply added as a
loop pass before the transformation, the pass is skipped if it is compiled at
–O0 or if it is explicitly disabled by the user, causing the compiler to
generate incorrect code. Furthermore, as a loop pass it will rotate all loops
instead of just the relevant loops.

We provide a utility interface for the loop rotation so that the loop rotation
can be called on demand. The changeset is as follows:

- Create a new file lib/Transforms/Utils/LoopRotationUtils.cpp and move the main
  implementation of class LoopRotate into this file.
- Create a new file llvm/include/Transform/Utils/LoopRotationUtils.h with the
  interface LoopRotation(...).
- Original LoopRotation.cpp is changed to use the utility function LoopRotation
  in LoopRotationUtils.cpp. This is done in the same way community did for
  mem-to-reg implementation.

Patch by Jin Lin!

Differential Revision: https://reviews.llvm.org/D44595

llvm-svn: 328766
2018-03-29 08:48:15 +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