60 Commits

Author SHA1 Message Date
Nikita Popov
a667526e7f
[MachineFunctionPass] Preserve more IR analyses (#178871)
Preserve, PDT, BPI, LazyBPI and LazyBFI. These are all IR analysis that
are not invalidated by machine passes.

This partially mitigates the compile-time regression from
https://github.com/llvm/llvm-project/pull/174746.
2026-02-02 09:25:30 +01:00
Shubham Sandeep Rastogi
92f916faba
Add a pass to collect dropped var statistics for MIR (#126686)
This patch attempts to reland
https://github.com/llvm/llvm-project/pull/120780 while addressing the
issues that caused the patch to be reverted.

Namely:

1. The patch had included code from the llvm/Passes directory in the
llvm/CodeGen directory.

2. The patch increased the backend compile time by 2% due to adding a
very expensive include in MachineFunctionPass.h

The patch has been re-structured so that there is no dependency between
the llvm/Passes and llvm/CodeGen directory, by moving the base class,
`class DroppedVariableStats` to the llvm/IR directory.

The expensive include in MachineFunctionPass.h has been changed to
contain forward declarations instead of other header includes which was
pulling a ton of code into MachineFunctionPass.h and should resolve any
issues when it comes to compile time increase.
2025-02-12 14:08:18 -08:00
NAKAMURA Takumi
d328d41061 Revert "Add a pass to collect dropped var stats for MIR (#120780)"
This reverts commit 3bf91ad2a9c75dd045961e45fdd830fd7b7a5455.
(llvmorg-20-init-16123-g3bf91ad2a9c7)

`llvm/CodeGen` should not depend on `llvm/Passes`.
2024-12-21 12:42:26 +09:00
Shubham Sandeep Rastogi
3bf91ad2a9
Add a pass to collect dropped var stats for MIR (#120780)
This patch uses the DroppedVariableStats class to add dropped variable
statistics for MIR passes.

Reland 1c082c9cd12efaa67a32c5da89a328c458ed51c5
2024-12-20 10:08:54 -08:00
Shubham Sandeep Rastogi
16d952898f Revert "Add a pass to collect dropped var stats for MIR (#120501)"
This reverts commit 223c7648468cd4f649a578d3f9cbc27a63523192.

Reverted due to vuildbot failure:

flang-aarch64-libcxx

Linking CXX shared library lib/libLLVMAnalysis.so.20.0git
FAILED: lib/libLLVMAnalysis.so.20.0git
2024-12-19 00:48:40 -08:00
Shubham Sandeep Rastogi
223c764846
Add a pass to collect dropped var stats for MIR (#120501)
Reland "Add a pass to collect dropped var stats for MIR" (#117044)

I am trying to reland https://github.com/llvm/llvm-project/pull/115566

I also moved the DroppedVariableStats code to the Analysis lib

This is part of a stack of patches with
https://github.com/llvm/llvm-project/pull/120502 being the first one in
the stack
2024-12-19 00:41:48 -08:00
Shubham Sandeep Rastogi
d8b5af4504 Revert "Reland "Add a pass to collect dropped var stats for MIR" (#117044)"
This reverts commit 249755cedb17ffa707253edcef1a388f807caa35.

Broke https://lab.llvm.org/buildbot/#/builders/160/builds/9420

Note: This is test shard 99 of 154.
[==========] Running 2 tests from 2 test suites.
[----------] Global test environment set-up.
[----------] 1 test from DroppedVariableStatsMIR
[ RUN      ] DroppedVariableStatsMIR.InlinedAt

--
exit: -11
2024-12-03 12:50:13 -08:00
Shubham Sandeep Rastogi
249755cedb
Reland "Add a pass to collect dropped var stats for MIR" (#117044)
Moved the MIR Test to the unittests/CodeGen folder

This is patch is part of a stack of patches, and follows
https://github.com/llvm/llvm-project/pull/117042

I moved the MIR test to the unittests/CodeGen folder 

I am trying to reland https://github.com/llvm/llvm-project/pull/115566
2024-12-03 12:37:30 -08:00
Shubham Sandeep Rastogi
81924ac1fb Revert "Add a pass to collect dropped var stats for MIR. (#115566)"
This reverts commit 6e2b77d4696d4a672635c0ba1ead4824e2158a7d.

Reverting due to buildbot failure:

unittests/IR/CMakeFiles/IRTests.dir/DroppedVariableStatsIRTest.cpp.o:DroppedVariableStatsIRTest.cpp:function llvm::DroppedVariableStatsIR::runAfterPass(llvm::StringRef, llvm::Any): error: undefined reference to 'llvm::DroppedVariableStatsIR::runOnModule(llvm::Module const*, bool)'
2024-11-18 16:05:09 -08:00
Shubham Sandeep Rastogi
6e2b77d469
Add a pass to collect dropped var stats for MIR. (#115566)
This patch uses the DroppedVariableStats class to add dropped variable
statistics for MIR passes.
2024-11-18 15:56:06 -08:00
Nikita Popov
4169338e75
[IR] Don't include Module.h in Analysis.h (NFC) (#97023)
Replace it with a forward declaration instead. Analysis.h is pulled in
by all passes, but not all passes need to access the module.
2024-06-28 14:30:47 +02:00
Matt Arsenault
5e15997291
MachineFunctionPass: Clear properties before running function (#67962)
This ensures !isSSA checks in the function work if the input MIR
happened to appear as SSA.
2023-10-05 15:11:47 -07:00
Arthur Eubanks
7e0a52e8e9 [NFC][MachineFunctionPass] Only lookup pass name if we request printing
Should report the small compile time regression reported in D133055.
2022-09-07 21:38:00 -07:00
Fangrui Song
8d95fd7e56 [MachineFunctionPass] Support -filter-passes for -print-changed
[MachineFunctionPass] Support -filter-passes for -print-changed

-filter-passes specifies a `PassID` (a lower-case dashed-separated pass name,
also used by -print-after, -stop-after, etc) instead of a CamelCasePass.

`-filter-passes=CamelCaseNewPMPass` seems like a workaround for new PM passes before
we can use lower-case dashed-separated pass names (as used by `-passes=`).

Example:
```
# getPassName() is "IRTranslator". PassID is "irtranslator"
llc -mtriple=aarch64 -print-changed -filter-passes=irtranslator < print-changed-machine.ll
```

Close https://github.com/llvm/llvm-project/issues/57453

Reviewed By: aeubanks

Differential Revision: https://reviews.llvm.org/D133055
2022-09-01 11:06:06 -07:00
Fangrui Song
2b70bebc6d [MachineFunctionPass] Support -print-changed={,c}diff{,-quiet}
Follow-up to D130434.
Move doSystemDiff to PrintPasses.cpp and call it in MachineFunctionPass.cpp.

Reviewed By: aeubanks

Differential Revision: https://reviews.llvm.org/D130833
2022-08-01 12:56:15 -07:00
Fangrui Song
f106525de2 [MachineFunctionPass] Support -print-changed and -print-changed=quiet
-print-changed for new pass manager is handy beside -print-after-all.
Port it to MachineFunctionPass.

Note: lib/Passes/StandardInstrumentations.cpp implements a number of
misc features. If we want to use them for codegen, we may need to lift
some functionality to LLVMIR.

Reviewed By: aeubanks, jamieschmeiser

Differential Revision: https://reviews.llvm.org/D130434
2022-07-26 10:16:49 -07:00
serge-sans-paille
989f1c72e0 Cleanup codegen includes
This is a (fixed) recommit of https://reviews.llvm.org/D121169

after:  1061034926
before: 1063332844

Discourse thread: https://discourse.llvm.org/t/include-what-you-use-include-cleanup
Differential Revision: https://reviews.llvm.org/D121681
2022-03-16 08:43:00 +01:00
Nico Weber
a278250b0f Revert "Cleanup codegen includes"
This reverts commit 7f230feeeac8a67b335f52bd2e900a05c6098f20.
Breaks CodeGenCUDA/link-device-bitcode.cu in check-clang,
and many LLVM tests, see comments on https://reviews.llvm.org/D121169
2022-03-10 07:59:22 -05:00
serge-sans-paille
7f230feeea Cleanup codegen includes
after:  1061034926
before: 1063332844

Differential Revision: https://reviews.llvm.org/D121169
2022-03-10 10:00:30 +01:00
dfukalov
2ce38b3f03 [NFC] Reduce include files dependency.
1. Removed #include "...AliasAnalysis.h" in other headers and modules.
2. Cleaned up includes in AliasAnalysis.h.

Reviewed By: RKSimon

Differential Revision: https://reviews.llvm.org/D92489
2020-12-03 18:25:05 +03:00
Yuanfang Chen
cc382cf727 [NewPM] Port MachineModuleInfo to the new pass manager.
Existing clients are converted to use MachineModuleInfoWrapperPass. The
new interface is for defining a new pass manager API in CodeGen.

Reviewers: fedor.sergeev, philip.pfaffe, chandlerc, arsenm

Reviewed By: arsenm, fedor.sergeev

Differential Revision: https://reviews.llvm.org/D64183

llvm-svn: 373240
2019-09-30 17:54:50 +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
Jessica Paquette
54fbfaeace Add size remarks to MachineFunctionPass
This adds per-function size remarks to codegen, similar to what we have in the
IR layer as of r341588. This only impacts MachineFunctionPasses.

This does the same thing, but for `MachineInstr`s instead of just
`Instructions`. After this, when a `MachineFunctionPass` modifies the number of
`MachineInstr`s in the function it ran on, you'll get a remark.

To enable this, use the size-info analysis remark as before.

llvm-svn: 341876
2018-09-10 22:24:10 +00:00
Matthias Braun
90ad6835dd CodeGen: Remove pipeline dependencies on StackProtector; NFC
This re-applies r336929 with a fix to accomodate for the Mips target
scheduling multiple SelectionDAG instances into the pass pipeline.

PrologEpilogInserter and StackColoring depend on the StackProtector analysis
being alive from the point it is run until PEI, which requires that they are all
scheduled in the same FunctionPassManager. Inserting a (machine) ModulePass
between StackProtector and PEI results in these passes being in separate
FunctionPassManagers and the StackProtector is not available for PEI.

PEI and StackColoring don't use much information from the StackProtector pass,
so transfering the required information to MachineFrameInfo is cleaner than
keeping the StackProtector pass around. This commit moves the SSP layout
information to MFI instead of keeping it in the pass.

This patch set (D37580, D37581, D37582, D37583, D37584, D37585, D37586, D37587)
is a first draft of the pagerando implementation described in
http://lists.llvm.org/pipermail/llvm-dev/2017-June/113794.html.

Patch by Stephen Crane <sjc@immunant.com>

Differential Revision: https://reviews.llvm.org/D49256

llvm-svn: 336964
2018-07-13 00:08:38 +00:00
Matthias Braun
f03f32d478 Revert "(HEAD -> master, origin/master, arcpatch-D37582) CodeGen: Remove pipeline dependencies on StackProtector; NFC"
This was triggering pass scheduling failures.

This reverts commit r336929.

llvm-svn: 336934
2018-07-12 19:27:01 +00:00
Matthias Braun
9436570cbd CodeGen: Remove pipeline dependencies on StackProtector; NFC
PrologEpilogInserter and StackColoring depend on the StackProtector analysis
being alive from the point it is run until PEI, which requires that they are all
scheduled in the same FunctionPassManager. Inserting a (machine) ModulePass
between StackProtector and PEI results in these passes being in separate
FunctionPassManagers and the StackProtector is not available for PEI.

PEI and StackColoring don't use much information from the StackProtector pass,
so transfering the required information to MachineFrameInfo is cleaner than
keeping the StackProtector pass around. This commit moves the SSP layout
information to MFI instead of keeping it in the pass.

This patch set (D37580, D37581, D37582, D37583, D37584, D37585, D37586, D37587)
is a first draft of the pagerando implementation described in
http://lists.llvm.org/pipermail/llvm-dev/2017-June/113794.html.

Patch by Stephen Crane <sjc@immunant.com>

Differential Revision: https://reviews.llvm.org/D49256

llvm-svn: 336929
2018-07-12 18:33:32 +00:00
Matthias Braun
7bda195812 CodeGen: Refactor MIR parsing
When parsing .mir files immediately construct the MachineFunctions and
put them into MachineModuleInfo.

This allows us to get rid of the delayed construction (and delayed error
reporting) through the MachineFunctionInitialzier interface.

Differential Revision: https://reviews.llvm.org/D33809

llvm-svn: 304758
2017-06-06 00:44:35 +00:00
Serge Pavlov
ed5eb93384 Reverted: Track validity of pass results
Commits r291882 and related r291887.

llvm-svn: 292062
2017-01-15 10:23:18 +00:00
Serge Pavlov
d409411ef1 Track validity of pass results
Running tests with expensive checks enabled exhibits some problems with
verification of pass results.

First, the pass verification may require results of analysis that are not
available. For instance, verification of loop info requires results of dominator
tree analysis. A pass may be marked as conserving loop info but does not need to
be dependent on DominatorTreePass. When a pass manager tries to verify that loop
info is valid, it needs dominator tree, but corresponding analysis may be
already destroyed as no user of it remained.

Another case is a pass that is skipped. For instance, entities with linkage
available_externally do not need code generation and such passes are skipped for
them. In this case result verification must also be skipped.

To solve these problems this change introduces a special flag to the Pass
structure to mark passes that have valid results. If this flag is reset,
verifications dependent on the pass result are skipped.

Differential Revision: https://reviews.llvm.org/D27190

llvm-svn: 291882
2017-01-13 06:09:54 +00:00
Quentin Colombet
c437aa9c26 [MFProperties][NFC] Rename clear into reset to match BitVector naming.
The name clear is used to reset all the bit in bitvectors and using it
to reset just properties was confusing.

llvm-svn: 279873
2016-08-26 22:09:08 +00:00
Matthias Braun
733fe3676c CodeGen: Remove MachineFunctionAnalysis => Enable (Machine)ModulePasses
Re-apply this patch, hopefully I will get away without any warnings
in the constructor now.

This patch removes the MachineFunctionAnalysis. Instead we keep a
map from IR Function to MachineFunction in the MachineModuleInfo.

This allows the insertion of ModulePasses into the codegen pipeline
without breaking it because the MachineFunctionAnalysis gets dropped
before a module pass.

Peak memory should stay unchanged without a ModulePass in the codegen
pipeline: Previously the MachineFunction was freed at the end of a codegen
function pipeline because the MachineFunctionAnalysis was dropped; With
this patch the MachineFunction is freed after the AsmPrinter has
finished.

Differential Revision: http://reviews.llvm.org/D23736

llvm-svn: 279602
2016-08-24 01:52:46 +00:00
Richard Smith
8c3fbdc6c4 Revert r279564. It introduces undefined behavior (binding a reference to a
dereferenced null pointer) in MachineModuleInfo::MachineModuleInfo that causes
-Werror builds (including several buildbots) to fail.

llvm-svn: 279580
2016-08-23 22:08:27 +00:00
Matthias Braun
4c1f1f120c CodeGen: Remove MachineFunctionAnalysis => Enable (Machine)ModulePasses
Re-apply this commit with the deletion of a MachineFunction delegated to
a separate pass to avoid use after free when doing this directly in
AsmPrinter.

This patch removes the MachineFunctionAnalysis. Instead we keep a
map from IR Function to MachineFunction in the MachineModuleInfo.

This allows the insertion of ModulePasses into the codegen pipeline
without breaking it because the MachineFunctionAnalysis gets dropped
before a module pass.

Peak memory should stay unchanged without a ModulePass in the codegen
pipeline: Previously the MachineFunction was freed at the end of a codegen
function pipeline because the MachineFunctionAnalysis was dropped; With
this patch the MachineFunction is freed after the AsmPrinter has
finished.

Differential Revision: http://reviews.llvm.org/D23736

llvm-svn: 279564
2016-08-23 20:58:29 +00:00
Matthias Braun
7f66202d38 Revert "(HEAD -> master, origin/master, origin/HEAD) CodeGen: Remove MachineFunctionAnalysis => Enable (Machine)ModulePasses"
Reverting while tracking down a use after free.

This reverts commit r279502.

llvm-svn: 279503
2016-08-23 05:17:11 +00:00
Matthias Braun
fd936841eb CodeGen: Remove MachineFunctionAnalysis => Enable (Machine)ModulePasses
This patch removes the MachineFunctionAnalysis. Instead we keep a
map from IR Function to MachineFunction in the MachineModuleInfo.

This allows the insertion of ModulePasses into the codegen pipeline
without breaking it because the MachineFunctionAnalysis gets dropped
before a module pass.

Peak memory should stay unchanged without a ModulePass in the codegen
pipeline: Previously the MachineFunction was freed at the end of a codegen
function pipeline because the MachineFunctionAnalysis was dropped; With
this patch the MachineFunction is freed after the AsmPrinter has
finished.

Differential Revision: http://reviews.llvm.org/D23736

llvm-svn: 279502
2016-08-23 03:20:09 +00:00
Matthias Braun
a7d6fc9618 MachineFunction: Cleanup/simplify MachineFunctionProperties::print()
- Always compile print() regardless of LLVM_ENABLE_DUMP. (We usually
  only gard dump() functions with that).
- Only show the set properties to reduce output clutter.
- Remove the unused variant that even shows the unset properties.
- Fix comments

llvm-svn: 279338
2016-08-19 22:31:45 +00:00
Dehao Chen
1a44452b11 [PM] Convert IVUsers analysis to new pass manager.
Summary: Convert IVUsers analysis to new pass manager.

Reviewers: davidxl, silvas

Subscribers: junbuml, sanjoy, llvm-commits, mzolotukhin

Differential Revision: https://reviews.llvm.org/D22434

llvm-svn: 275698
2016-07-16 22:51:33 +00:00
Derek Schuff
025191d42f Improve error message reporting for MachineFunctionProperties
When printing the properties required by a pass, only print the
properties that are set, and not those that are clear (only properties
that are set are verified, clear properties are "don't-care").

llvm-svn: 267070
2016-04-21 22:19:24 +00:00
Derek Schuff
07636cd5e7 Add a print method to MachineFunctionProperties for better error messages
This makes check failures much easier to understand.
Make it empty (but leave it in the class) for NDEBUG builds.

Differential Revision: http://reviews.llvm.org/D18529

llvm-svn: 264780
2016-03-29 20:28:20 +00:00
Derek Schuff
ad154c837e Introduce MachineFunctionProperties and the AllVRegsAllocated property
MachineFunctionProperties represents a set of properties that a MachineFunction
can have at particular points in time. Existing examples of this idea are
MachineRegisterInfo::isSSA() and MachineRegisterInfo::tracksLiveness() which
will eventually be switched to use this mechanism.
This change introduces the AllVRegsAllocated property; i.e. the property that
all virtual registers have been allocated and there are no VReg operands
left.

With this mechanism, passes can declare that they require a particular property
to be set, or that they set or clear properties by implementing e.g.
MachineFunctionPass::getRequiredProperties(). The MachineFunctionPass base class
verifies that the requirements are met, and handles the setting and clearing
based on the delcarations. Passes can also directly query and update the current
properties of the MF if they want to have conditional behavior.

This change annotates the target-independent post-regalloc passes; future
changes will also annotate target-specific ones.

Reviewers: qcolombet, hfinkel

Differential Revision: http://reviews.llvm.org/D18421

llvm-svn: 264593
2016-03-28 17:05:30 +00:00
Chandler Carruth
61440d225b [PM] Port memdep to the new pass manager.
This is a fairly straightforward port to the new pass manager with one
exception. It removes a very questionable use of releaseMemory() in
the old pass to invalidate its caches between runs on a function.
I don't think this is really guaranteed to be safe. I've just used the
more direct port to the new PM to address this by nuking the results
object each time the pass runs. While this could cause some minor malloc
traffic increase, I don't expect the compile time performance hit to be
noticable, and it makes the correctness and other aspects of the pass
much easier to reason about. In some cases, it may make things faster by
making the sets and maps smaller with better locality. Indeed, the
measurements collected by Bruno (thanks!!!) show mostly compile time
improvements.

There is sadly very limited testing at this point as there are only two
tests of memdep, and both rely on GVN. I'll be porting GVN next and that
will exercise this heavily though.

Differential Revision: http://reviews.llvm.org/D17962

llvm-svn: 263082
2016-03-10 00:55:30 +00:00
Hongbin Zheng
751337faa7 Introduce DominanceFrontierAnalysis to the new PassManager to compute DominanceFrontier. NFC
Differential Revision: http://reviews.llvm.org/D17570

llvm-svn: 261903
2016-02-25 17:54:15 +00:00
Hongbin Zheng
ad782ce3f7 Revert "Introduce DominanceFrontierAnalysis to the new PassManager to compute DominanceFrontier. NFC"
This reverts commit 109c38b2226a87b0be73fa7a0a8c1a81df20aeb2.

llvm-svn: 261890
2016-02-25 16:45:46 +00:00
Hongbin Zheng
237197ba63 Introduce DominanceFrontierAnalysis to the new PassManager to compute DominanceFrontier. NFC
Differential Revision: http://reviews.llvm.org/D17570

llvm-svn: 261883
2016-02-25 16:33:15 +00:00
Chandler Carruth
7b560d40bd [PM/AA] Rebuild LLVM's alias analysis infrastructure in a way compatible
with the new pass manager, and no longer relying on analysis groups.

This builds essentially a ground-up new AA infrastructure stack for
LLVM. The core ideas are the same that are used throughout the new pass
manager: type erased polymorphism and direct composition. The design is
as follows:

- FunctionAAResults is a type-erasing alias analysis results aggregation
  interface to walk a single query across a range of results from
  different alias analyses. Currently this is function-specific as we
  always assume that aliasing queries are *within* a function.

- AAResultBase is a CRTP utility providing stub implementations of
  various parts of the alias analysis result concept, notably in several
  cases in terms of other more general parts of the interface. This can
  be used to implement only a narrow part of the interface rather than
  the entire interface. This isn't really ideal, this logic should be
  hoisted into FunctionAAResults as currently it will cause
  a significant amount of redundant work, but it faithfully models the
  behavior of the prior infrastructure.

- All the alias analysis passes are ported to be wrapper passes for the
  legacy PM and new-style analysis passes for the new PM with a shared
  result object. In some cases (most notably CFL), this is an extremely
  naive approach that we should revisit when we can specialize for the
  new pass manager.

- BasicAA has been restructured to reflect that it is much more
  fundamentally a function analysis because it uses dominator trees and
  loop info that need to be constructed for each function.

All of the references to getting alias analysis results have been
updated to use the new aggregation interface. All the preservation and
other pass management code has been updated accordingly.

The way the FunctionAAResultsWrapperPass works is to detect the
available alias analyses when run, and add them to the results object.
This means that we should be able to continue to respect when various
passes are added to the pipeline, for example adding CFL or adding TBAA
passes should just cause their results to be available and to get folded
into this. The exception to this rule is BasicAA which really needs to
be a function pass due to using dominator trees and loop info. As
a consequence, the FunctionAAResultsWrapperPass directly depends on
BasicAA and always includes it in the aggregation.

This has significant implications for preserving analyses. Generally,
most passes shouldn't bother preserving FunctionAAResultsWrapperPass
because rebuilding the results just updates the set of known AA passes.
The exception to this rule are LoopPass instances which need to preserve
all the function analyses that the loop pass manager will end up
needing. This means preserving both BasicAAWrapperPass and the
aggregating FunctionAAResultsWrapperPass.

Now, when preserving an alias analysis, you do so by directly preserving
that analysis. This is only necessary for non-immutable-pass-provided
alias analyses though, and there are only three of interest: BasicAA,
GlobalsAA (formerly GlobalsModRef), and SCEVAA. Usually BasicAA is
preserved when needed because it (like DominatorTree and LoopInfo) is
marked as a CFG-only pass. I've expanded GlobalsAA into the preserved
set everywhere we previously were preserving all of AliasAnalysis, and
I've added SCEVAA in the intersection of that with where we preserve
SCEV itself.

One significant challenge to all of this is that the CGSCC passes were
actually using the alias analysis implementations by taking advantage of
a pretty amazing set of loop holes in the old pass manager's analysis
management code which allowed analysis groups to slide through in many
cases. Moving away from analysis groups makes this problem much more
obvious. To fix it, I've leveraged the flexibility the design of the new
PM components provides to just directly construct the relevant alias
analyses for the relevant functions in the IPO passes that need them.
This is a bit hacky, but should go away with the new pass manager, and
is already in many ways cleaner than the prior state.

Another significant challenge is that various facilities of the old
alias analysis infrastructure just don't fit any more. The most
significant of these is the alias analysis 'counter' pass. That pass
relied on the ability to snoop on AA queries at different points in the
analysis group chain. Instead, I'm planning to build printing
functionality directly into the aggregation layer. I've not included
that in this patch merely to keep it smaller.

Note that all of this needs a nearly complete rewrite of the AA
documentation. I'm planning to do that, but I'd like to make sure the
new design settles, and to flesh out a bit more of what it looks like in
the new pass manager first.

Differential Revision: http://reviews.llvm.org/D12080

llvm-svn: 247167
2015-09-09 17:55:00 +00:00
Chandler Carruth
2f1fd1658f [PM] Port ScalarEvolution to the new pass manager.
This change makes ScalarEvolution a stand-alone object and just produces
one from a pass as needed. Making this work well requires making the
object movable, using references instead of overwritten pointers in
a number of places, and other refactorings.

I've also wired it up to the new pass manager and added a RUN line to
a test to exercise it under the new pass manager. This includes basic
printing support much like with other analyses.

But there is a big and somewhat scary change here. Prior to this patch
ScalarEvolution was never *actually* invalidated!!! Re-running the pass
just re-wired up the various other analyses and didn't remove any of the
existing entries in the SCEV caches or clear out anything at all. This
might seem OK as everything in SCEV that can uses ValueHandles to track
updates to the values that serve as SCEV keys. However, this still means
that as we ran SCEV over each function in the module, we kept
accumulating more and more SCEVs into the cache. At the end, we would
have a SCEV cache with every value that we ever needed a SCEV for in the
entire module!!! Yowzers. The releaseMemory routine would dump all of
this, but that isn't realy called during normal runs of the pipeline as
far as I can see.

To make matters worse, there *is* actually a key that we don't update
with value handles -- there is a map keyed off of Loop*s. Because
LoopInfo *does* release its memory from run to run, it is entirely
possible to run SCEV over one function, then over another function, and
then lookup a Loop* from the second function but find an entry inserted
for the first function! Ouch.

To make matters still worse, there are plenty of updates that *don't*
trip a value handle. It seems incredibly unlikely that today GVN or
another pass that invalidates SCEV can update values in *just* such
a way that a subsequent run of SCEV will incorrectly find lookups in
a cache, but it is theoretically possible and would be a nightmare to
debug.

With this refactoring, I've fixed all this by actually destroying and
recreating the ScalarEvolution object from run to run. Technically, this
could increase the amount of malloc traffic we see, but then again it is
also technically correct. ;] I don't actually think we're suffering from
tons of malloc traffic from SCEV because if we were, the fact that we
never clear the memory would seem more likely to have come up as an
actual problem before now. So, I've made the simple fix here. If in fact
there are serious issues with too much allocation and deallocation,
I can work on a clever fix that preserves the allocations (while
clearing the data) between each run, but I'd prefer to do that kind of
optimization with a test case / benchmark that shows why we need such
cleverness (and that can test that we actually make it faster). It's
possible that this will make some things faster by making the SCEV
caches have higher locality (due to being significantly smaller) so
until there is a clear benchmark, I think the simple change is best.

Differential Revision: http://reviews.llvm.org/D12063

llvm-svn: 245193
2015-08-17 02:08:17 +00:00
Chandler Carruth
71f308adb7 Re-sort #include lines using my handy dandy ./utils/sort_includes.py
script. This is in preparation for changes to lots of include lines.

llvm-svn: 229088
2015-02-13 09:09:03 +00:00
Chandler Carruth
b81dfa6378 [LPM] Stop using the string based preservation API. It is an
abomination.

For starters, this API is incredibly slow. In order to lookup the name
of a pass it must take a memory fence to acquire a pointer to the
managed static pass registry, and then potentially acquire locks while
it consults this registry for information about what passes exist by
that name. This stops the world of LLVMs in your process no matter
how little they cared about the result.

To make this more joyful, you'll note that we are preserving many passes
which *do not exist* any more, or are not even analyses which one might
wish to have be preserved. This means we do all the work only to say
"nope" with no error to the user.

String-based APIs are a *bad idea*. String-based APIs that cannot
produce any meaningful error are an even worse idea. =/

I have a patch that simply removes this API completely, but I'm hesitant
to commit it as I don't really want to perniciously break out-of-tree
users of the old pass manager. I'd rather they just have to migrate to
the new one at some point. If others disagree and would like me to kill
it with fire, just say the word. =]

llvm-svn: 227294
2015-01-28 04:57:56 +00:00
Josh Magee
22b8ba2d67 [stackprotector] Use analysis from the StackProtector pass for stack layout in PEI a nd LocalStackSlot passes.
This changes the MachineFrameInfo API to use the new SSPLayoutKind information
produced by the StackProtector pass (instead of a boolean flag) and updates a
few pass dependencies (to preserve the SSP analysis).

The stack layout follows the same approach used prior to this change - i.e.,
only LargeArray stack objects will be placed near the canary and everything
else will be laid out normally.  After this change, structures containing large
arrays will also be placed near the canary - a case previously missed by the
old implementation.

Out of tree targets will need to update their usage of
MachineFrameInfo::CreateStackObject to remove the MayNeedSP argument. 

The next patch will implement the rules for sspstrong and sspreq.  The end goal
is to support ssp-strong stack layout rules.

WIP.

Differential Revision: http://llvm-reviews.chandlerc.com/D2158

llvm-svn: 197653
2013-12-19 03:17:11 +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