Commit Graph

9652 Commits

Author SHA1 Message Date
Matt Davis 0f70bc05b3 [llvm-mca] Set the Selection strategy to Default if nullptr is passed.
* Set (not reset) the strategy in Scheduler::setCustomStrategyImpl()

llvm-svn: 340566
2018-08-23 18:42:37 +00:00
Andrea Di Biagio 354d1cc718 [llvm-mca] Fix wrong call to setCustomStrategy().
Thanks to @waltl for reporting this issue.

I have also added an assert to check for invalid null strategy objects, and I
have reworded a couple of code comments in Scheduler.h

llvm-svn: 340545
2018-08-23 17:09:08 +00:00
Andrea Di Biagio 1715efd7ff [llvm-mca] Allow the definition of custom strategies for selecting processor resource units.
With this patch, users can now customize the pipeline selection strategy for
scheduler resources. The resource selection strategy can be defined at processor
resource granularity. This enables the definition of different strategies for
different hardware schedulers.

To override the strategy associated with a processor resource, users can call
method ResourceManager::setCustomStrategy(), and pass a 'ResourceStrategy'
object in input.

Class ResourceStrategy is an abstract class which declares virtual method
`ResourceStrategy::select()`. Method select() is meant to implement the actual
strategy; it is responsible for picking the next best resource from a set of
available pipeline resources.  Custom strategy must simply override that method.

By default, processor resources are associated with instances of
'DefaultResourceStrategy'.  A 'DefaultResourceStrategy' internally implements a
simple round-robin selector. For more details, please refer to the code comments
in Scheduler.h.

llvm-svn: 340536
2018-08-23 15:04:52 +00:00
Victor Leschuk cf1f714d3b [DWARF] Unify warning callbacks. NFC.
Both DWARFDebugLine and DWARFDebugAddr used the same callback mechanism
for handling recoverable errors. They both implemented similar warn() function
to be used as such callbacks.

In this revision we get rid of code duplication and move this warn() function
to DWARFContext as DWARFContext::dumpWarning().

Reviewers: lhames, jhenderson, aprantl, probinson, dblaikie, JDevlieghere

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D51033

llvm-svn: 340528
2018-08-23 12:43:33 +00:00
Peter Collingbourne bc3089f45f MC: Teach the COFF object writer to write address-significance tables.
The format is the same as in ELF: a sequence of ULEB128-encoded
symbol indexes.

Differential Revision: https://reviews.llvm.org/D51047

llvm-svn: 340499
2018-08-22 23:58:16 +00:00
Chris Bieneman dc622702aa [CMake] Use LLVM_ENABLE_IDE instead of CMAKE_CONFIGURATION_TYPES
There are several places where we use CMAKE_CONFIGURATION_TYPES to determine if we are using an IDE generator and in turn decide not to generate some of the convenience targets (like all the install-* and check-llvm-* targets). This decision is made because IDEs don't always deal well with the thousands of targets LLVM can generate.

This approach does not work for Visual Studio 15's new CMake integration. Because VS15 uses a Ninja generator, it isn't a multi-configuration build, and generating all these extra targets mucks up the UI and adds little value.

With this change we still don't generate these targets by default for Visual Studio and Xcode generators, and LLVM_ENABLE_IDE becomes a switch that can be enabled on the VS15 CMake builds, to improve the IDE experience.

llvm-svn: 340435
2018-08-22 18:40:24 +00:00
Matt Davis 9cee1adc1a [llvm-mca] Clean up a comment about the Context class. NFC.
llvm-svn: 340431
2018-08-22 18:03:58 +00:00
Matt Davis 4fc7e6a1e9 [llvm-mca] Remove unused decl. NFC.
llvm-svn: 340422
2018-08-22 17:15:25 +00:00
Andrea Di Biagio 4660fd25d1 [llvm-mca] Improved code comments and moved some method definitions from Scheduler.h to Scheduler.cpp. NFC
llvm-svn: 340395
2018-08-22 10:23:28 +00:00
Fangrui Song 9ba5740ba5 [gold] -thinlto-object-suffix-replace: don't append new suffix if path does not end with old suffix
Summary: This is to be consistent with lld behavior since rLLD340364.

Reviewers: tejohnson

Reviewed By: tejohnson

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

Differential Revision: https://reviews.llvm.org/D51060

llvm-svn: 340380
2018-08-22 02:11:36 +00:00
Zachary Turner 4ca11217fc Print "invalid mangled name" when we can't demangle something.
llvm-svn: 340340
2018-08-21 21:23:29 +00:00
Matt Davis 8e3f093baa [llvm-mca] Remove unused decl. NFC.
llvm-svn: 340316
2018-08-21 18:39:20 +00:00
Andrea Di Biagio f3374f04ad [llvm-mca] Add the ability to customize the instruction selection strategy in the Scheduler.
The constructor of Scheduler now accepts a SchedulerStrategy object, which is
used internally by method Scheduler::select() to drive the instruction selection
process.

The goal of this patch is to enable the definition of custom selection
strategies while reusing the same algorithms implemented by class Scheduler.
The motivation is that, on some targets, the default strategy may not well
approximate the selection logic in the hardware schedulers.

This patch also adds the ability to pass a ResourceManager object to the
constructor of Scheduler. This gives a bit more flexibility to the design, and
potentially it allows to expose processor resources to SchedulerStrategy
objects.

Differential Revision: https://reviews.llvm.org/D51051

llvm-svn: 340314
2018-08-21 18:20:16 +00:00
Peter Collingbourne 7d1790868f llvm-readobj: Simplify. NFCI.
llvm-svn: 340305
2018-08-21 17:18:18 +00:00
Andrea Di Biagio 5001f90b01 [llvm-mca] Replace use of llvm::any_of with std::any_of.
This should unbreak the buildbots.

llvm-svn: 340274
2018-08-21 13:00:44 +00:00
Andrea Di Biagio 5184995f9b [llvm-mca] Add method cycleEvent() to class Scheduler. NFCI
The goal of this patch is to simplify the Scheduler's interface in preparation
for D50929.
Some methods in the Scheduler's interface should not be exposed to external
users, since their presence makes it hard to both understand, and extend the
Scheduler's interface.

This patch removes the following two methods from the public Scheduler's API:
 - reclaimSimulatedResources()
 - updatePendingQueue()
Their logic has been migrated to a new method named 'cycleEvent()'.

Methods 'updateIssuedSet()' and 'promoteToReadySet()' still exist. However,
they are now private members of class Scheduler.

This simplifies the interaction with the Scheduler from the ExecuteStage.

llvm-svn: 340273
2018-08-21 12:40:15 +00:00
Fangrui Song 0e49ef9540 [llvm-objcopy] Simplify find(X,Y) != X.end() with is_contained()
llvm-svn: 340241
2018-08-21 00:13:52 +00:00
Fangrui Song ffbc3e2576 [llvm-strip] Allow only one input
Summary: Before, llvm-strip accepted a second argument but it would just be ignored.

Reviewers: alexshap, jhenderson, paulsemel

Reviewed By: alexshap

Subscribers: jakehehrlich, rupprecht, llvm-commits

Differential Revision: https://reviews.llvm.org/D51004

llvm-svn: 340229
2018-08-20 23:01:57 +00:00
Matt Davis accb51152c [llvm-mca] Remove unused formal parameter. NFC.
llvm-svn: 340227
2018-08-20 22:41:27 +00:00
Zachary Turner 030ad37ef4 [llvm-objdump] Add ability to demangle COFF symbols.
llvm-svn: 340221
2018-08-20 22:18:21 +00:00
Andrea Di Biagio 0875e759f0 [llvm-mca] Make the LSUnit a HardwareUnit, and allow derived classes to implement a different memory consistency model.
The LSUnit is now a HardwareUnit, and it is owned by the mca::Context.
Derived classes can now implement a different consistency model by overriding
method `LSUnit::isReady()`.

This patch also slightly refactors the Scheduler interface in the attempt to
simplifying the interaction between ExecuteStage and the underlying Scheduler.

llvm-svn: 340176
2018-08-20 14:41:36 +00:00
Simon Pilgrim bbd2d15d45 Use LLVM_BUILTIN_TRAP not __builtin_trap to appease windows builds. NFCI.
llvm-svn: 340162
2018-08-20 09:49:20 +00:00
Kirill Bobyrev 5f26a642e6 [llvm] Make YAML serialization up to 2.5 times faster
This patch significantly improves performance of the YAML serializer by
optimizing `YAML::isNumeric` function. This function is called on the
most strings and is highly inefficient for two reasons:

* It uses `Regex`, which is parsed and compiled each time this
  function is called
* It uses multiple passes which are not necessary

This patch introduces stateful ad hoc YAML number parser which does not
rely on `Regex`. It also fixes YAML number format inconsistency: current
implementation supports C-stile octal number format (`01234567`) which
was present in YAML 1.0 specialization (http://yaml.org/spec/1.0/),
[Section 2.4. Tags, Example 2.19] but was deprecated and is no longer
present in latest YAML 1.2 specification
(http://yaml.org/spec/1.2/spec.html), see [Section 10.3.2. Tag
Resolution]. Since the rest of the rest of the implementation does not
support other deprecated YAML 1.0 numeric features such as sexagecimal
numbers, commas as delimiters it is treated as inconsistency and not
longer supported. This patch also adds unit tests to ensure the validity
of proposed implementation.

This performance bottleneck was identified while profiling Clangd's
global-symbol-builder tool with my colleague @ilya-biryukov. The
substantial part of the runtime was spent during a single-thread Reduce
phase, which concludes with YAML serialization of collected symbol
collection. Regex matching was accountable for approximately 45% of the
whole runtime (which involves sharded Map phase), now it is reduced to
18% (which is spent in `clang::clangd::CanonicalIncludes` and can be
also optimized because all used regexes are in fact either suffix
matches or exact matches).

`llvm-yaml-numeric-parser-fuzzer` was used to ensure the validity of the
proposed regex replacement. Fuzzing for ~60 hours using 10 threads did
not expose any bugs.

Benchmarking `global-symbol-builder` (using `hyperfine --warmup 2
--min-runs 5 'command 1' 'command 2'`) tool by processing a reasonable
amount of code (26 source files matched by
`clang-tools-extra/clangd/*.cpp` with all transitive includes) confirmed
our understanding of the performance bottleneck nature as it speeds up
the command by the factor of 1.6x:

| Command | Mean [s] | Min…Max [s] |
| this patch (D50839) | 84.7 ± 0.6 | 83.3…84.7 |
| master (rL339849) | 133.1 ± 0.8 | 132.4…134.6 |

Using smaller samples (e.g. by collecting symbols from
`clang-tools-extra/clangd/AST.cpp` only) yields even better performance
improvement, which is expected because Map phase takes less time
compared to Reduce and is 2.05x faster and therefore would significantly
improve the performance of standalone YAML serializations.

| Command | Mean [ms] | Min…Max [ms] |
| this patch (D50839) | 3702.2 ± 48.7 | 3635.1…3752.3 |
| master (rL339849) | 7607.6 ± 109.5 | 7533.3…7796.4 |

Reviewed by: zturner, ilya-biryukov

Differential revision: https://reviews.llvm.org/D50839

llvm-svn: 340154
2018-08-20 07:00:36 +00:00
whitequark fdca0c6d2e [bindings/go] Add coroutine passes
Add Go bindings for CoroEarly, CoroSplit, CoroElide and CoroCleanup.

Differential Revision: https://reviews.llvm.org/D50951

llvm-svn: 340148
2018-08-19 23:40:05 +00:00
whitequark b56a4d3149 [C-API][DIBuilder] Added DIFlags in LLVMDIBuilderCreateBasicType
Added DIFlags in LLVMDIBuilderCreateBasicType to add optional DWARF
attributes, such as DW_AT_endianity.

Patch by Chirag Patel.

Differential Revision: https://reviews.llvm.org/D50832

llvm-svn: 340146
2018-08-19 23:39:47 +00:00
Jordan Rupprecht be8ebccaed [llvm-objcopy] Implement -G/--keep-global-symbol(s).
Summary:
Port GNU Objcopy -G/--keep-global-symbol(s).

This is slightly different than the already-implemented --globalize-symbol, which marks a symbol as global when copying. When --keep-global-symbol (alias -G) is used, *only* those symbols marked will stay global, and all other globals are demoted to local. (Also note that it doesn't *promote* a symbol to global). Additionally, there is a pluralized version of the flag --keep-global-symbols, which effectively applies --keep-global-symbol for every non-comment in a file.

Reviewers: jakehehrlich, jhenderson, alexshap

Reviewed By: jhenderson

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D50589

llvm-svn: 340105
2018-08-17 22:34:48 +00:00
Lang Hames d5f56c5979 [ORC] Rename VSO to JITDylib.
VSO was a little close to VDSO (an acronym on Linux for Virtual Dynamic Shared
Object) for comfort. It also risks giving the impression that instances of this
class could be shared between ExecutionSessions, which they can not.

JITDylib seems moderately less confusing, while still hinting at how this
class is intended to be used, i.e. as a JIT-compiled stand-in for a dynamic
library (code that would have been a dynamic library if you had wanted to
compile it ahead of time).

llvm-svn: 340084
2018-08-17 21:18:18 +00:00
Jordan Rupprecht cf67633e66 [llvm-objcopy] Add support for -I binary -B <arch>.
Summary:
The -I (--input-target) and -B (--binary-architecture) flags exist but are currently silently ignored. This adds support for -I binary for architectures i386, x86-64 (and alias i386:x86-64), arm, aarch64, sparc, and ppc (powerpc:common64). This is largely based on D41687.

This is done by implementing an additional subclass of Reader, BinaryReader, which works by interpreting the input file as contents for .data field, sets up a synthetic header, and adds additional sections/symbols (e.g. _binary__tmp_data_txt_start).

Reviewers: jakehehrlich, alexshap, jhenderson, javed.absar

Reviewed By: jhenderson

Subscribers: jyknight, nemanjai, kbarton, fedor.sergeev, jrtc27, kristof.beyls, paulsemel, llvm-commits

Differential Revision: https://reviews.llvm.org/D50343

llvm-svn: 340070
2018-08-17 18:51:11 +00:00
Matt Davis 06ac6af297 [llvm-mca] Reformat a few lines (fix spacing). NFC.
llvm-svn: 340065
2018-08-17 18:06:01 +00:00
Andrea Di Biagio 163419f976 [llvm-mca] Removed references to HWStallEvent in Scheduler.h. NFCI
class Scheduler should not know anything of hardware event listeners and
hardware stall events (HWStallEvent).  HWStallEvent objects should only be
constructed by pipeline stages to notify listeners of hardware events.

No functional change intended.

llvm-svn: 340036
2018-08-17 15:01:37 +00:00
Brian Cain f72611b4d2 [llvm-mc-assemble-fuzzer] Update API - Pass MCObjectWriter instead of a stream
Fixes build breakage of llvm-mc-assemble-fuzzer introduced by r332749.

Fix provided by pbhatu (Pratik Bhatu)

llvm-svn: 339981
2018-08-17 04:38:41 +00:00
Andrea Di Biagio 998373c059 [llvm-mca] Fix -Wpessimizing-move warnings introduced by r339923.
Reported by buildbot `clang-with-lto-ubuntu` ( build #9858 ).

llvm-svn: 339928
2018-08-16 19:45:13 +00:00
Andrea Di Biagio db63088ea7 [llvm-mca] Refactor how execution is orchestrated by the Pipeline.
This patch changes how instruction execution is orchestrated by the Pipeline.
In particular, this patch makes it more explicit how instructions transition
through the various pipeline stages during execution.

The main goal is to simplify both the stage API and the Pipeline execution.  At
the same time, this patch fixes some design issues which are currently latent,
but that are likely to cause problems in future if people start defining custom
pipelines.

The new design assumes that each pipeline stage knows the "next-in-sequence".
The Stage API has gained three new methods:
 -   isAvailable(IR)
 -   checkNextStage(IR)
 -   moveToTheNextStage(IR).

An instruction IR can be executed by a Stage if method `Stage::isAvailable(IR)`
returns true.
Instructions can move to next stages using method moveToTheNextStage(IR).
An instruction cannot be moved to the next stage if method checkNextStage(IR)
(called on the current stage) returns false.
Stages are now responsible for moving instructions to the next stage in sequence
if necessary.

Instructions are allowed to transition through multiple stages during a single
cycle (as long as stages are available, and as long as all the calls to
`checkNextStage(IR)` returns true).

Methods `Stage::preExecute()` and `Stage::postExecute()` have now become
redundant, and those are removed by this patch.

Method Pipeline::runCycle() is now simpler, and it correctly visits stages
on every begin/end of cycle.

Other changes:
 - DispatchStage no longer requires a reference to the Scheduler.
 - ExecuteStage no longer needs to directly interact with the
   RetireControlUnit. Instead, executed instructions are now directly moved to the
   next stage (i.e. the retire stage).
 - RetireStage gained an execute method. This allowed us to remove the
   dependency with the RCU in ExecuteStage.
 - FecthStage now updates the "program counter" during cycleBegin() (i.e.
   before we start executing new instructions).
 - We no longer need Stage::Status to be returned by method execute(). It has
   been dropped in favor of a more lightweight llvm::Error.

Overally, I measured a ~11% performance gain w.r.t. the previous design.  I also
think that the Stage interface is probably easier to read now.  That being said,
code comments have to be improved, and I plan to do it in a follow-up patch.

Differential revision: https://reviews.llvm.org/D50849

llvm-svn: 339923
2018-08-16 19:00:48 +00:00
Jordan Rupprecht d1767dc56f [llvm-strip] Add support for -p/--preserve-dates
Summary: [llvm-strip] Preserve access/modification timestamps when -p is used.

Reviewers: jakehehrlich, jhenderson, alexshap

Reviewed By: jhenderson

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D50744

llvm-svn: 339921
2018-08-16 18:29:40 +00:00
Andrea Di Biagio 492816d8e1 [llvm-mca] Small refactoring in preparation for another patch that will improve the modularity of the Pipeline. NFCI
The main difference is that now `cycleStart()` and `cycleEnd()` return an
llvm::Error.

This patch implements a few minor style changes, and adds missing 'const' to
some methods.

llvm-svn: 339885
2018-08-16 15:43:09 +00:00
George Rimar d2f90ea337 [yaml2obj] - Allow to use numeric sh_link (Link) value for sections.
That change allows using numeric values for Link field.
It is consistent with the code for another fields in this method.

llvm-svn: 339873
2018-08-16 12:44:17 +00:00
George Rimar 7f2df7df45 [yaml2elf] - Simplify code, add a test. NFC.
This simplifies the code allowing to set the sh_info
for relocations sections. And adds a missing test.

llvm-svn: 339870
2018-08-16 12:23:22 +00:00
Andrea Di Biagio 9eb111566e [llvm-mca] Minor style changes. NFC
llvm-svn: 339823
2018-08-15 22:11:05 +00:00
George Rimar 942e8ed19d [yaml2obj] - Teach yaml2obj to produce SHT_GROUP section with a custom Info field.
This allows to set custom Info field value for SHT_GROUP sections.

It is useful to allow this because we would be able to replace at least one binary
object committed in LLD and replace it with the yaml2obj based test.

Differential revision: https://reviews.llvm.org/D50776

llvm-svn: 339772
2018-08-15 13:55:22 +00:00
Andrea Di Biagio a03f2a77f8 [llvm-mca] Fix PR38575: Avoid an invalid implicit truncation of a processor resource mask (an uint64_t value) to unsigned.
This patch fixes a regression introduced at revision 338702.

A processor resource mask was incorrectly implicitly truncated to an unsigned
quantity. Later on, the truncated mask was used to initialize an element of a
vector of processor resource descriptors.
On targets with more than 32 processor resources, some elements of the vector
are left uninitialized. As a consequence, this bug might have eventually caused
a crash due to null dereference in the Scheduler.

This patch fixes PR38575, and adds a test for it.

llvm-svn: 339768
2018-08-15 12:53:38 +00:00
George Rimar 5290af8ad9 [yaml2obj] - Teach tool to produce SHT_GROUP section with a custom type.
Currently, it is possible to use yaml2obj for producing SHT_GROUP sections
of type GRP_COMDAT. For LLD test case I need to produce an object with
a broken (different from GRP_COMDAT) type.

The patch teaches tool to do such things.

Differential revision: https://reviews.llvm.org/D50761

llvm-svn: 339764
2018-08-15 11:43:00 +00:00
Jordan Rupprecht 97ea485041 [Support] NFC: Allow modifying access/modification times independently in sys::fs::setLastModificationAndAccessTime.
Summary:
Add an overload to sys::fs::setLastModificationAndAccessTime that allows setting last access and modification times separately. This will allow tools to use this API when they want to preserve both the access and modification times from an input file, which may be different.

Also note that both the POSIX (futimens/futimes) and Windows (SetFileTime) APIs take the two timestamps in the order of (1) access (2) modification time, so this renames the method to "setLastAccessAndModificationTime" to make it clear which timestamp is which.

For existing callers, the 1-arg overload just sets both timestamps to the same thing.

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D50521

llvm-svn: 339628
2018-08-13 23:03:45 +00:00
Jordan Rupprecht 6b575395d4 [llvm-objcopy] NFC: Fix minor formatting issues
llvm-svn: 339616
2018-08-13 21:30:27 +00:00
Matt Davis 4bcf369d9b [llvm-mca] Propagate fatal llvm-mca errors from library classes to driver.
Summary:
This patch introduces error handling to propagate the errors from llvm-mca library classes (or what will become library classes) up to the driver.  This patch also introduces an enum to make clearer the intention of the return value for Stage::execute.

This supports PR38101.

Reviewers: andreadb, courbet, RKSimon

Reviewed By: andreadb

Subscribers: llvm-commits, tschuett, gbedwell

Differential Revision: https://reviews.llvm.org/D50561

llvm-svn: 339594
2018-08-13 18:11:48 +00:00
Matt Davis 99a1ce9717 [llvm-mca] Make InstrBuilder::getOrCreateInstrDesc private. NFC.
llvm-svn: 339468
2018-08-10 20:24:27 +00:00
Jordan Rupprecht de965ea87b [llvm-objcopy] NFC: consistently use typename ELFT::<X> definitions in headers
llvm-svn: 339448
2018-08-10 16:25:58 +00:00
Jordan Rupprecht 88ed5e59bd [llvm-objcopy] NFC: Add some color to error()
llvm-svn: 339404
2018-08-09 22:52:03 +00:00
Paul Semel 7a3dc2c184 [llvm-objcopy] Add --prefix-symbols option
Differential Revision: https://reviews.llvm.org/D50381

llvm-svn: 339362
2018-08-09 17:49:04 +00:00
Paul Semel a42dec7a1b [llvm-objcopy] Add --dump-section
Differential Revision: https://reviews.llvm.org/D49979

llvm-svn: 339358
2018-08-09 17:05:21 +00:00
Hans Wennborg 79cf42e869 vs integration: bump version number
llvm-svn: 339330
2018-08-09 11:57:36 +00:00
Hans Wennborg 0d35871a53 vs integration: update the manifest to require VS 2017
It previously erroneously said only VS2015 was required.

llvm-svn: 339329
2018-08-09 11:52:48 +00:00
Petr Hosek 7b27454477 [ADT] Normalize empty triple components
LLVM triple normalization is handling "unknown" and empty components
differently; for example given "x86_64-unknown-linux-gnu" and
"x86_64-linux-gnu" which should be equivalent, triple normalization
returns "x86_64-unknown-linux-gnu" and "x86_64--linux-gnu". autoconf's
config.sub returns "x86_64-unknown-linux-gnu" for both
"x86_64-linux-gnu" and "x86_64-unknown-linux-gnu". This changes the
triple normalization to behave the same way, replacing empty triple
components with "unknown".

This addresses PR37129.

Differential Revision: https://reviews.llvm.org/D50219

llvm-svn: 339294
2018-08-08 22:23:57 +00:00
Vedant Kumar e302fc597a [Coverage] Delete getCounterMismatches, it's dead code (NFC)
Exactly one counted region is inserted into a function record for every
region in a coverage mapping.

llvm-svn: 339193
2018-08-07 22:25:22 +00:00
Nico Weber 875f6dae86 Update msbuild integration warnings: Don't warn on /Zi and /X
We do need to map /Zi to /Z7 explicitly for msbuild as explained in this file,
but since /Zi is passed by default and since things transparently work fine
with it mapped to /Z7, we shouldn't produce effectively inactionable noise for
it.

Also don't warn on /X since clang-cl supports that (since r326357; the risk of
duplicating a bunch of clang-cl driver logic here).

https://reviews.llvm.org/D50398

llvm-svn: 339169
2018-08-07 19:55:12 +00:00
David Bolvansky ab2cbad6fe [RFC] Build LLVM-C.dll on MSVC that exports only the C API
Summary:
Hello!

This commit adds a LLVM-C target that is always built on MSVC. A big fat warning, this is my first cmake code ever so there is a fair bit of I-have-no-idea-what-I'm-doing going on here. Which is also why I placed it outside of llvm-shlib as I was afraid of breaking things of other people. Secondly llvm-shlib builds a LLVM.so which exports all symbols and then does a thin library that points to it, but on Windows we do not build a LLVM.dll so that would have complicated the code more.

The patch includes a python script that calls dumpbin.exe to get all of the symbols from the built libraries. It then grabs all the symbols starting with LLVM and generates the export file from those. The export file is then used to create the library just like the LLVM-C that is built on darwin.

Improvements that I need help with, to follow up this review.
  - Get cmake to make sure that dumpbin.exe is on the path and wire the full path to the script.
  - Use LLVM-C.dll when building llvm-c-test so we can verify that the symbols are exported.
  - Bundle the LLVM-C.dll with the windows installer.

Why do this?  I'm building a language frontend which is self-hosting, and on windows because of various tooling issues we have a problem of consuming the LLVM*.lib directly on windows. Me and the users of my projects using LLVM would be greatly helped by having LLVM-C.dll built and shipped by the Windows installer. Not only does LLVM takes forever to build, you have to run a extra python script in order to get the final DLL.

Any comments, thoughts or help is greatly appreciated.

Cheers, Jakob.

Patch by: Wallbraker (Jakob Bornecrantz)

Reviewers: compnerd, beanz, hans, smeenai

Reviewed By: beanz

Subscribers: xbolva00, bhelyer, Memnarch, rnk, fedor.sergeev, chapuni, smeenai, john.brawn, deadalnix, llvm-commits, mgorny

Differential Revision: https://reviews.llvm.org/D35077

llvm-svn: 339151
2018-08-07 15:54:50 +00:00
Pavel Labath 2f0881160c [DebugInfo] Reduce debug_str_offsets section size
Summary:
The accelerator tables use the debug_str section to store their strings.
However, they do not support the indirect method of access that is
available for the debug_info section (DW_FORM_strx et al.).

Currently our code is assuming that all strings can/will be referenced
indirectly, and puts all of them into the debug_str_offsets section.
This is generally true for regular (unsplit) dwarf, but in the DWO case,
most of the strings in the debug_str section will only be used from the
accelerator tables. Therefore the contents of the debug_str_offsets
section will be largely unused and bloating the main executable.

This patch rectifies this by teaching the DwarfStringPool to
differentiate between strings accessed directly and indirectly. When a
user inserts a string into the pool it has to declare whether that
string will be referenced directly or not. If at least one user requsts
indirect access, that string will be assigned an index ID and put into
debug_str_offsets table. Otherwise, the offset table is skipped.

This approach reduces the overall binary size (when compiled with
-gdwarf-5 -gsplit-dwarf) in my tests by about 2% (debug_str_offsets is
shrunk by 99%).

Reviewers: probinson, dblaikie, JDevlieghere

Subscribers: aprantl, mgrang, llvm-commits

Differential Revision: https://reviews.llvm.org/D49493

llvm-svn: 339122
2018-08-07 09:54:52 +00:00
Hans Wennborg f5678b1276 vs integration: bump version number
llvm-svn: 339119
2018-08-07 09:27:05 +00:00
Hans Wennborg f79f22e46c vs integration: update the publisher name
llvm-svn: 339118
2018-08-07 09:15:16 +00:00
Hans Wennborg 68e07d4d6f vs integration: fix default path to clang-cl
Differential Revision: https://reviews.llvm.org/D50335

llvm-svn: 339117
2018-08-07 09:02:06 +00:00
George Rimar 65a6828b17 [yaml2obj] - Add a support for changing EntSize.
I was trying to add a test case for LLD and found that it
is impossible to set sh_entsize via yaml.
The patch implements the missing part.

Differential revision: https://reviews.llvm.org/D50235

llvm-svn: 339113
2018-08-07 08:11:38 +00:00
Alexandre Ganea 741cc3531a [llvm-pdbutil] Support PDBs without a DBI stream
Differential Revision: https://reviews.llvm.org/D50258

llvm-svn: 339045
2018-08-06 19:35:00 +00:00
Fangrui Song 96ce589d46 [llvm-objdump] Remove continue after report_error which is unreachable
llvm-svn: 338951
2018-08-04 05:19:00 +00:00
Andrea Di Biagio 1c3bcc6ce5 [llvm-mca] Speed up the computation of the wait/ready/issued sets in the Scheduler.
This patch is a follow-up to r338702.

We don't need to use a map to model the wait/ready/issued sets. It is much more
efficient to use a vector instead.

This patch gives us an average 7.5% speedup (on top of the ~12% speedup obtained
after r338702).

llvm-svn: 338883
2018-08-03 12:55:28 +00:00
Guillaume Chatelet e60866a4e0 [llvm-exegesis] Renaming classes and functions.
Summary: Functional No Op.

Reviewers: gchatelet

Subscribers: tschuett, courbet, llvm-commits

Differential Revision: https://reviews.llvm.org/D50231

llvm-svn: 338836
2018-08-03 09:29:38 +00:00
Dean Michael Berris 2c4dcf0576 [XRay][tools] Use Support/JSON.h in llvm-xray convert
Summary:
This change removes the ad-hoc implementation used by llvm-xray's
`convert` subcommand to generate JSON encoded catapult (AKA Chrome
Trace Viewer) trace output, to instead use the JSON encoder now in the
Support library.

Reviewers: kpw, zturner, eizan

Reviewed By: kpw

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D50129

llvm-svn: 338834
2018-08-03 09:21:31 +00:00
Dave Lee 3fb120f12e objdump: Better handling of Mach-O universal binaries
Summary:
With Mach-O, there is a flag requirement discrepancy between working with
universal binaries and thin binaries. Many flags that don't require the `-macho`
flag (for example `-private-headers` and `-disassemble`) fail to work on
universal binaries unless `-macho` is given. When this happens, the error
message is unhelpful, stating:

    The file was not recognized as a valid object file.

Which can lead to confusion.

This change allows generic flags to be used on universal binaries with and
without the `-macho` flag. This means flags that can be used for thin files can
be used consistently with fat files too.

To do this, the universal binary support within `ParseInputMachO()` is extracted
into a new function. This new function is called directly from `DumpInput()`
when the input binary is universal. Additionally the `-arch` flag validation in
`ParseInputMachO()` was extracted to be reused.

Reviewers: compnerd

Reviewed By: compnerd

Subscribers: keith, llvm-commits

Differential Revision: https://reviews.llvm.org/D48702

llvm-svn: 338792
2018-08-03 00:06:38 +00:00
Paul Robinson 96545db374 [DebugInfo/DWARF] Remove redundant iterator type. NFC
llvm-svn: 338759
2018-08-02 19:29:38 +00:00
Puyan Lotfi 97604b4f09 [NFC] clang-format cleanup of a couple files in llvm-objcopy.
llvm-svn: 338752
2018-08-02 18:16:52 +00:00
Tom Stellard 910f70238c CMake: Remove LLVM_DYLIB_SYMBOL_VERSIONING
Summary:
This option is no longer needed since r300496 added symbol
versioning by default

Reviewers: sylvestre.ledru, beanz, mgorny

Reviewed By: mgorny

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D49835

llvm-svn: 338751
2018-08-02 18:16:10 +00:00
Zachary Turner bd45adb50f Update the LLVM VS integration to sign the assembly.
llvm-svn: 338740
2018-08-02 17:20:31 +00:00
Ben Dunbobbin a318e2c603 [llvm-ar] Correct help text
Corrected and simplified the help text.

It was clearly too difficult to maintain before (see e.g. @227296) making it
simpler and more consistent it should help people keep it up to date.

Differential Revision: https://reviews.llvm.org/D48577

llvm-svn: 338703
2018-08-02 11:27:38 +00:00
Andrea Di Biagio c2619a2f3d [llvm-mca] Use a vector to store ResourceState objects in the ResourceManager.
We don't need to use a map to store ResourceState objects. The number of
processor resources is known statically from the scheduling model. We can
therefore use a vector, and reserve a slot for each processor resource that we
want to simulate.
Every time the ResourceManager queries the ResourceState vector, the index to
the vector of ResourceState objects can be easily computed from the processor
resource mask.

This drastically reduces the time complexity of method ResourceManager::use() and
method ResourceManager::release(). This patch gives an average speedup of 12%.

llvm-svn: 338702
2018-08-02 11:12:35 +00:00
Guillaume Chatelet 171f3f46c8 [llvm-exegesis] Rename InstructionInstance into InstructionBuilder.
Summary: Non functional change.

Subscribers: tschuett, courbet, llvm-commits

Differential Revision: https://reviews.llvm.org/D50176

llvm-svn: 338701
2018-08-02 11:12:02 +00:00
Jordan Rupprecht 175ef5f29e [llvm-objcopy] Add missing -I command line flag alias for --input-target
llvm-svn: 338635
2018-08-01 20:59:39 +00:00
Zachary Turner 3a758e22df [llvm-undname Add an option to dump back references.
This is useful for understanding how our demangler processes
back references and for investigating issues related to
back references.  But it's a feature only useful for debugging
the demangling process itself, so I'm marking it hidden.

llvm-svn: 338609
2018-08-01 18:33:04 +00:00
Jordan Rupprecht d67c1e129b [llvm-objcopy] Add support for --rename-section flags from gnu objcopy
Summary:
Add support for --rename-section flags from gnu objcopy.

Not all flags appear to have an effect for ELF objects, but allowing them would allow easier drop-in replacement. Other unrecognized flags are rejected.

This was only tested by comparing flags printed by "readelf -e <.o>" against the output of gnu vs llvm objcopy, it hasn't been tested to be valid beyond that.

Reviewers: jakehehrlich, alexshap

Subscribers: llvm-commits, paulsemel, alexshap

Differential Revision: https://reviews.llvm.org/D49870

llvm-svn: 338582
2018-08-01 16:23:22 +00:00
Andrea Di Biagio 7f3bf5c1f9 [llvm-mca] Correctly update the rank in `Scheduler::select()`.
Found by inspection.

llvm-svn: 338579
2018-08-01 16:06:33 +00:00
Guillaume Chatelet fb94354d2d [llvm-exegesis] Provide a way to handle memory instructions.
Summary:
And implement memory instructions on X86.

This fixes PR36906.

Reviewers: gchatelet

Reviewed By: gchatelet

Subscribers: lebedev.ri, filcab, mgorny, tschuett, RKSimon, llvm-commits

Differential Revision: https://reviews.llvm.org/D48935

llvm-svn: 338567
2018-08-01 14:41:45 +00:00
Jonas Devlieghere 5361767210 [dsymutil] Convert recursion in lookForDIEsToKeep into worklist.
The functions `lookForDIEsToKeep` and `keepDIEAndDependencies` can have
some very deep recursion. This tackles part of this problem by removing
the recursion from `lookForDIEsToKeep` by turning it into a worklist.

The difficulty in doing so is the computation of incompleteness, which
depends on the incompleteness of its children. To compute this, we
insert "continuation markers" into the worklist. This informs the work
loop to (re)compute the incompleteness property of the DIE associated
with it (i.e. the parent of the previously processed DIE).

This patch should generate byte-identical output. Unfortunately it also
has some impact of performance, regressing by about 4% when processing
clang on my machine.

Differential revision: https://reviews.llvm.org/D48899

llvm-svn: 338536
2018-08-01 13:24:39 +00:00
Andrea Di Biagio 5291df3c98 [llvm-mca] Improve code comments. NFC.
llvm-svn: 338513
2018-08-01 10:49:01 +00:00
Fangrui Song 87b4b8f7b4 [llvm-objcopy] Make --strip-debug strip .gdb_index
Summary:
See binutils-gdb/bfd/elf.c, GNU objcopy also strips .stab* (STABS)
.line* (DWARF 1) .gnu.linkonce.wi.* (linkonce section for .debug_info) but
I'm not sure we need to be compatible with it.

Reviewers: dblaikie, alexshap, jakehehrlich, jhenderson

Reviewed By: alexshap, jakehehrlich

Subscribers: aprantl, JDevlieghere, jakehehrlich, llvm-commits

Differential Revision: https://reviews.llvm.org/D50100

llvm-svn: 338443
2018-07-31 21:26:35 +00:00
Matt Davis 5ceaa98a4e [llvm-mca] Update the help text to reflect "physical" registers. NFC.
llvm-svn: 338430
2018-07-31 20:05:08 +00:00
Alexandre Ganea ee8a720051 [CodeView] Minimal support for S_UNAMESPACE records
Differential Revision: https://reviews.llvm.org/D50007

llvm-svn: 338417
2018-07-31 19:15:50 +00:00
Andrea Di Biagio 4a31bcff3f [llvm-mca] Remove README.txt
A detailed description of the tool has been recently added by Matt to
CommandGuide/llvm-mca.rst. File README.txt is now redundant and can be removed;
all the relevant user-guide information has been improved and then moved to
llvm-mca.rst.

In future, we should add another .rst for the "llvm-mca developer manual" to
provide infromation about:
 - llvm-mca internals.
 - How to add custom stages to the simulated pipeline.
 - How to provide extra processor info in the scheduling model to improve the
   analysis performed by llvm-mca.

llvm-svn: 338386
2018-07-31 14:23:49 +00:00
Andrea Di Biagio a1852b6194 [llvm-mca][BtVer2] Teach how to identify dependency-breaking idioms.
This patch teaches llvm-mca how to identify dependency breaking instructions on
btver2.

An example of dependency breaking instructions is the zero-idiom XOR (example:
`XOR %eax, %eax`), which always generates zero regardless of the actual value of
the input register operands.
Dependency breaking instructions don't have to wait on their input register
operands before executing. This is because the computation is not dependent on
the inputs.

Not all dependency breaking idioms are also zero-latency instructions. For
example, `CMPEQ %xmm1, %xmm1` is independent on
the value of XMM1, and it generates a vector of all-ones.
That instruction is not eliminated at register renaming stage, and its opcode is
issued to a pipeline for execution. So, the latency is not zero. 

This patch adds a new method named isDependencyBreaking() to the MCInstrAnalysis
interface. That method takes as input an instruction (i.e. MCInst) and a
MCSubtargetInfo.
The default implementation of isDependencyBreaking() conservatively returns
false for all instructions. Targets may override the default behavior for
specific CPUs, and return a value which better matches the subtarget behavior.

In future, we should teach to Tablegen how to automatically generate the body of
isDependencyBreaking from scheduling predicate definitions. This would allow us
to expose the knowledge about dependency breaking instructions to the machine
schedulers (and, potentially, other codegen passes).

Differential Revision: https://reviews.llvm.org/D49310

llvm-svn: 338372
2018-07-31 13:21:43 +00:00
Jonas Devlieghere ae1727e3dd [dsymutil] Simplify temporary file handling.
Dsymutil's update functionality was broken on Windows because we tried
to rename a file while we're holding open handles to that file. TempFile
provides a solution for this through its keep(Twine) method. This patch
changes dsymutil to make use of that functionality.

Differential revision: https://reviews.llvm.org/D49860

llvm-svn: 338216
2018-07-29 14:56:15 +00:00
Fangrui Song fdfe2a9236 [llvm-objcopy] Make --strip-debug strip .zdebug* (zlib-gnu) sections
This behavior matches GNU objcopy.

llvm-svn: 338173
2018-07-27 22:51:36 +00:00
Stephen Hines e6e75bf84c Handle the lack of a symbol table correctly.
Summary:
These two cases will trigger a dereference on a nullptr, since the
SymbolTable can be nonexistent for a given library, in addition to just
being empty.

Reviewers: alexshap

Reviewed By: alexshap

Subscribers: meikeb, kongyi, chh, jakehehrlich, llvm-commits, pirama

Differential Revision: https://reviews.llvm.org/D49534

llvm-svn: 338062
2018-07-26 20:05:31 +00:00
Michael Kruse 6f1da6e345 [ADT] Replace std::isprint by llvm::isPrint.
The standard library functions ::isprint/std::isprint have platform-
and locale-dependent behavior which makes LLVM's output less
predictable. In particular, regression tests my fail depending on the
implementation of these functions.

Implement llvm::isPrint in StringExtras.h with a standard behavior and
replace all uses of ::isprint/std::isprint by a call it llvm::isPrint.
The function is inlined and does not look up language settings so it
should perform better than the standard library's version.

Such a replacement has already been done for isdigit, isalpha, isxdigit
in r314883. gtest does the same in gtest-printers.cc using the following
justification:

    // Returns true if c is a printable ASCII character.  We test the
    // value of c directly instead of calling isprint(), which is buggy on
    // Windows Mobile.
    inline bool IsPrintableAscii(wchar_t c) {
      return 0x20 <= c && c <= 0x7E;
    }

Similar issues have also been encountered by Julia:
https://github.com/JuliaLang/julia/issues/7416

I noticed the problem myself when on Windows isprint('\t') started to
evaluate to true (see https://stackoverflow.com/questions/51435249) and
thus caused several unit tests to fail. The result of isprint doesn't
seem to be well-defined even for ASCII characters. Therefore I suggest
to replace isprint by a platform-independent version.

Differential Revision: https://reviews.llvm.org/D49680

llvm-svn: 338034
2018-07-26 15:31:41 +00:00
Dean Michael Berris bcbb032d55 [MCA] Avoid an InstrDesc copy in mca::LSUnit::reserve.
Summary:
InstrDesc contains 4 vectors (as well as some other data), so it's
expensive to copy.

Authored By: orodley

Reviewers: andreadb, mattd, dberris

Reviewed By: mattd, dberris

Subscribers: dberris, gbedwell, llvm-commits

Differential Revision: https://reviews.llvm.org/D49775

llvm-svn: 337985
2018-07-26 00:02:54 +00:00
Jonas Devlieghere 743d351120 [dsymutil] Add support for generating DWARF5 accelerator tables.
This patch add support for emitting DWARF5 accelerator tables
(.debug_names) from dsymutil. Just as with the Apple style accelerator
tables, it's possible to update existing dSYMs. This patch includes a
test that show how you can convert back and forth between the two types.

If no kind of table is specified, dsymutil will default to generating
Apple-style accelerator tables whenever it finds those in its input. The
same is true when there are no accelerator tables at all. Finally, in
the remaining case, where there's at least one DWARF v5 table and no
Apple ones, the output will contains a DWARF accelerator tables
(.debug_names).

Differential revision: https://reviews.llvm.org/D49137

llvm-svn: 337980
2018-07-25 23:01:38 +00:00
Paul Semel 0913dcd747 [llvm-objdump] Add dynamic section printing to private-headers option
Differential Revision: https://reviews.llvm.org/D49016

llvm-svn: 337902
2018-07-25 11:09:20 +00:00
Paul Semel 5ce8f1598c [llvm-readobj] Generic hex-dump option
Helpers are available to make this option file format independant. This
patch adds the feature for Wasm file format. It doesn't change the
behavior of the other file format handling.

Differential Revision: https://reviews.llvm.org/D49545

llvm-svn: 337896
2018-07-25 10:04:37 +00:00
Dean Michael Berris 833bb6fbdc llvm-xray: Broken chrome trace event format output
Summary:
Missing comma separator for EXIT and TAIL_EXIT RecordTypes emit invalid
JSON output for Chrome Trace Event Format.

Reviewers: dberris

Reviewed By: dberris

Subscribers: sammccall, kpw, llvm-commits

Differential Revision: https://reviews.llvm.org/D49687

llvm-svn: 337795
2018-07-24 01:45:34 +00:00
Andres Freund 376a3d3659 Add PerfJITEventListener for perf profiling support.
This new JIT event listener supports generating profiling data for
the linux 'perf' profiling tool, allowing it to generate function and
instruction level profiles.

Currently this functionality is not enabled by default, but must be
enabled with LLVM_USE_PERF=yes.  Given that the listener has no
dependencies, it might be sensible to enable by default once the
initial issues have been shaken out.

I followed existing precedent in registering the listener by default
in lli. Should there be a decision to enable this by default on linux,
that should probably be changed.

Please note that until https://reviews.llvm.org/D47343 is resolved,
using this functionality with mcjit rather than orcjit will not
reliably work.

Disregarding the previous comment, here's an example:

$ cat /tmp/expensive_loop.c

bool stupid_isprime(uint64_t num)
{
        if (num == 2)
                return true;
        if (num < 1 || num % 2 == 0)
                return false;
        for(uint64_t i = 3; i < num / 2; i+= 2) {
                if (num % i == 0)
                        return false;
        }
        return true;
}

int main(int argc, char **argv)
{
        int numprimes = 0;

        for (uint64_t num = argc; num < 100000; num++)
        {
                if (stupid_isprime(num))
                        numprimes++;
        }

        return numprimes;
}

$ clang -ggdb -S -c -emit-llvm /tmp/expensive_loop.c -o
/tmp/expensive_loop.ll

$ perf record -o perf.data -g -k 1 ./bin/lli -jit-kind=mcjit /tmp/expensive_loop.ll 1

$ perf inject --jit -i perf.data -o perf.jit.data

$ perf report -i perf.jit.data
-   92.59%  lli      jitted-5881-2.so                   [.] stupid_isprime
     stupid_isprime
     main
     llvm::MCJIT::runFunction
     llvm::ExecutionEngine::runFunctionAsMain
     main
     __libc_start_main
     0x4bf6258d4c544155
+    0.85%  lli      ld-2.27.so                         [.] do_lookup_x

And line-level annotations also work:
       │              for(uint64_t i = 3; i < num / 2; i+= 2) {
       │1 30:   movq   $0x3,-0x18(%rbp)
  0.03 │1 38:   mov    -0x18(%rbp),%rax
  0.03 │        mov    -0x10(%rbp),%rcx
       │        shr    $0x1,%rcx
  3.63 │     ┌──cmp    %rcx,%rax
       │     ├──jae    6f
       │     │                if (num % i == 0)
  0.03 │     │  mov    -0x10(%rbp),%rax
       │     │  xor    %edx,%edx
 89.00 │     │  divq   -0x18(%rbp)
       │     │  cmp    $0x0,%rdx
  0.22 │     │↓ jne    5f
       │     │                        return false;
       │     │  movb   $0x0,-0x1(%rbp)
       │     │↓ jmp    73
       │     │        }
  3.22 │1 5f:│↓ jmp    61
       │     │        for(uint64_t i = 3; i < num / 2; i+= 2) {

Subscribers: mgorny, llvm-commits

Differential Revision: https://reviews.llvm.org/D44892

llvm-svn: 337789
2018-07-24 00:54:06 +00:00
Vedant Kumar d6ff43cc71 [Debugify] Export per-pass debug info loss statistics
Add a -debugify-export option to opt. This exports per-pass `debugify`
loss statistics to a file in CSV format.

For some interesting numbers on debug value loss during an -O2 build
of the sqlite3 amalgamation, see the review thread.

Differential Revision: https://reviews.llvm.org/D49003

llvm-svn: 337787
2018-07-24 00:41:29 +00:00
Vedant Kumar ca407c4336 [Debugify] Move interface definitions to a header, NFC
This is a minor cleanup in preparation for a change to export DI
statistics from -check-debugify. To do that, it would be cleaner to have
a dedicated header for the debugify interface.

llvm-svn: 337786
2018-07-24 00:41:28 +00:00
Paul Semel 1dbbfba888 [yaml2obj] Add default sh_entsize for dynamic sections
Dynamic section holds a table, so the sh_entsize might be set. As the
dynamic section entry size never changes, we can default it to the size
of a dynamic entry.

Differential Revision: https://reviews.llvm.org/D49619

llvm-svn: 337725
2018-07-23 18:49:04 +00:00
Aaron Ballman e5bf489291 Fixing a typo; NFC.
llvm-svn: 337719
2018-07-23 18:09:43 +00:00
Zachary Turner c93b870c54 [llvm-undname] Flush output before demangling.
If an error occurs and we write it to stderr, it could appear
before we wrote the mangled name which we're undecorating.
By flushing stdout first, we ensure that the messages are always
sequenced in the correct order.

llvm-svn: 337645
2018-07-21 15:39:05 +00:00
Martin Storsjo 21524bed39 [llvm-undname] Remove a superfluous semicolon. NFC.
llvm-svn: 337615
2018-07-20 20:48:36 +00:00
Jordan Rupprecht db2036e1f5 [llvm-objcopy] Add basic support for --rename-section
Summary:
Add basic support for --rename-section=old=new to llvm-objcopy.

A full replacement for GNU objcopy requires also modifying flags (i.e. --rename-section=old=new,flag1,flag2); I'd like to keep that in a separate change to keep this simple.

Reviewers: jakehehrlich, alexshap

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D49576

llvm-svn: 337604
2018-07-20 19:54:24 +00:00
Zachary Turner f435a7eada Add a Microsoft Demangler.
This adds initial support for a demangling library (LLVMDemangle)
and tool (llvm-undname) for demangling Microsoft names.  This
doesn't cover 100% of cases and there are some known limitations
which I intend to address in followup patches, at least until such
time that we have (near) 100% test coverage matching up with all
of the test cases in clang/test/CodeGenCXX/mangle-ms-*.

Differential Revision: https://reviews.llvm.org/D49552

llvm-svn: 337584
2018-07-20 17:27:48 +00:00
Zachary Turner 83226b913d Rewrite the VS integration scripts.
This is a new modernized VS integration installer.  It adds a
Visual Studio .sln file which, when built, outputs a VSIX that can
be used to install ourselves as a "real" Visual Studio Extension.
We can even upload this extension to the visual studio marketplace.

This fixes a longstanding problem where we didn't support installing
into VS 2017 and higher.  In addition to supporting VS 2017, due
to the way this is written we now longer need to do anything special
to support future versions of VS as well.  Everything should
"just work".  This also fixes several bugs with our old integration,
such as MSBuild triggering full rebuilds when /Zi was used.

Finally, we add a new UI page called "LLVM" which becomes visible
when the LLVM toolchain is selected.  For now this only contains
one option which is the path to clang-cl.exe, but in the future
we can add more things here.

Differential Revision: https://reviews.llvm.org/D42762

llvm-svn: 337572
2018-07-20 16:30:02 +00:00
Reid Kleckner 310a4c2bfe Fix -Wsign-compare in llvm-readobj
llvm-svn: 337490
2018-07-19 19:58:22 +00:00
George Rimar a2b553b4c9 [llvm-readobj] - Do not report invalid amount of sections.
When output style is GNU and amount of sections is >= SHN_LORESERVE,
llvm-readobj reports zero number of sections instead of actual value.

The patch fixes that.

Differential revision: https://reviews.llvm.org/D49544

llvm-svn: 337462
2018-07-19 14:52:57 +00:00
Paul Semel 6e13790801 [llvm-readobj] Generic -string-dump option
Differential Revision: https://reviews.llvm.org/D49470

llvm-svn: 337408
2018-07-18 18:00:41 +00:00
Paul Semel 007dedbf77 [llvm-objdump] Add -demangle (-C) option
Differential Revision: https://reviews.llvm.org/D49043

llvm-svn: 337401
2018-07-18 16:39:21 +00:00
George Rimar c1090da852 [llvm-objdump] - An attempt to fix BB after r337361.
Seems r337361 is the reason of the following ARM BB failures:
http://lab.llvm.org:8011/builders/clang-cmake-armv8-quick
http://lab.llvm.org:8011/builders/clang-cmake-armv8-full/builds/4633

Reason is unclear to me, other bots are OK.
If this will not help, I'll revert r337361.

llvm-svn: 337371
2018-07-18 09:25:36 +00:00
George Rimar e35e6448f9 [llvm-objdump] - Stop reporting bogus section IDs.
Imagine we have a file with few sections, and one of them is .foo
with index N != 0.

Problem is that when llvm-objdump is given a -section=.foo parameter
it lists .foo as a section at index 0. That makes impossible to write
test cases which needs to find the index of the particular section,
while ignoring dumping of others.

The patch fixes that.

Differential revision: https://reviews.llvm.org/D49372

llvm-svn: 337361
2018-07-18 08:34:35 +00:00
George Rimar 6fdac3b23a [llvm-readobj] - Teach tool to dump objects with >= SHN_LORESERVE of sections.
http://www.sco.com/developers/gabi/2003-12-17/ch4.eheader.html

says that e_shnum and/or e_shstrndx may have special values if
"the number of sections is greater than or equal to SHN_LORESERVE" or
"the section name string table section index is greater than or equal to SHN_LORESERVE (0xff00)"

Previously llvm-readobj was unable to dump such files, patch changes that.

I had to add a precompiled test case because it does not seem possible to
prepare a test using yaml2obj or llvm-mc (not clear how to make .shstrtab
to have index >= SHN_LORESERVE).

Differential revision: https://reviews.llvm.org/D49369

llvm-svn: 337360
2018-07-18 08:19:58 +00:00
Puyan Lotfi 0f5d5fae93 [NFC][llvm-objcopy] Cleanup namespace usage in llvm-objcopy.
Nest any classes not used outside of a file into anon. Nest any classes used
across files in llvm-objcopy into namespace llvm::objcopy.


Differential Revision: https://reviews.llvm.org/D49449

llvm-svn: 337337
2018-07-18 00:10:51 +00:00
Peter Collingbourne 3e22733698 MC: Implement support for new .addrsig and .addrsig_sym directives.
Part of the address-significance tables proposal:
http://lists.llvm.org/pipermail/llvm-dev/2018-May/123514.html

Differential Revision: https://reviews.llvm.org/D47744

llvm-svn: 337328
2018-07-17 22:17:18 +00:00
Sam Clegg cf2a9e28b1 [WebAssembly] Remove ELF file support.
This support was partial and temporary.  Now that we have
wasm object file support its no longer needed.

Differential Revision: https://reviews.llvm.org/D48744

llvm-svn: 337222
2018-07-16 23:09:29 +00:00
Puyan Lotfi c4846a551e [NFC][llvm-objcopy] Make helper functions static
Anywhere in tools/llvm-objcopy where functions or classes are not referenced
outside of a given file, we change things to make the function or class static
or put inside an anonymous namespace.

llvm-svn: 337220
2018-07-16 22:17:05 +00:00
Jake Ehrlich c7f8ac7896 [llvm-objcopy] Add support for large indexes
This patch is an update of an older patch that never landed
(see here: https://reviews.llvm.org/D42516)

Recently various users have run into this issue and it just 100%
has to be solved at this point. The main difference in this patch
is that I use gunzip instead of unzip which should hopefully allow
tests to pass. Please review this as if it is a new patch however.
I found some issues along the way and made some minor modifications.

The binary used in this patch for testing (a zip file to make it small)
can be found here:
https://drive.google.com/file/d/1UjsnTO9edLttZibbr-2T1bJl92KEQFAO/view?usp=sharing

Differential Revision: https://reviews.llvm.org/D49206

llvm-svn: 337204
2018-07-16 19:48:52 +00:00
Teresa Johnson d68935c5ac Restore "[ThinLTO] Ensure we always select the same function copy to import"
This reverts commit r337081, therefore restoring r337050 (and fix in
r337059), with test fix for bot failure described after the original
description below.

In order to always import the same copy of a linkonce function,
even when encountering it with different thresholds (a higher one then a
lower one), keep track of the summary we decided to import.
This ensures that the backend only gets a single definition to import
for each GUID, so that it doesn't need to choose one.

Move the largest threshold the GUID was considered for import into the
current module out of the ImportMap (which is part of a larger map
maintained across the whole index), and into a new map just maintained
for the current module we are computing imports for. This saves some
memory since we no longer have the thresholds maintained across the
whole index (and throughout the in-process backends when doing a normal
non-distributed ThinLTO build), at the cost of some additional
information being maintained for each invocation of ComputeImportForModule
(the selected summary pointer for each import).

There is an additional map lookup for each callee being considered for
importing, however, this was able to subsume a map lookup in the
Worklist iteration that invokes computeImportForFunction. We also are
able to avoid calling selectCallee if we already failed to import at the
same or higher threshold.

I compared the run time and peak memory for the SPEC2006 471.omnetpp
benchmark (running in-process ThinLTO backends), as well as for a large
internal benchmark with a distributed ThinLTO build (so just looking at
the thin link time/memory). Across a number of runs with and without
this change there was no significant change in the time and memory.

(I tried a few other variations of the change but they also didn't
improve time or peak memory).

The new commit removes a test that no longer makes sense
(Transforms/FunctionImport/hotness_based_import2.ll), as exposed by the
reverse-iteration bot. The test depends on the order of processing the
summary call edges, and actually depended on the old problematic
behavior of selecting more than one summary for a given GUID when
encountered with different thresholds. There was no guarantee even
before that we would eventually pick the linkonce copy with the hottest
call edges, it just happened to work with the test and the old code, and
there was no guarantee that we would end up importing the selected
version of the copy that had the hottest call edges (since the backend
would effectively import only one of the selected copies).

Reviewers: davidxl

Subscribers: mehdi_amini, inglorion, llvm-commits

Differential Revision: https://reviews.llvm.org/D48670

llvm-svn: 337184
2018-07-16 15:30:27 +00:00
Joel Galenson 4099b249fb [cfi-verify] Abort on unsupported targets
As suggested in the review for r337007, this makes cfi-verify abort on unsupported targets instead of producing incorrect results.  It also updates the design document to reflect this.

Differential Revision: https://reviews.llvm.org/D49304

llvm-svn: 337181
2018-07-16 15:26:44 +00:00
Andrea Di Biagio ff630c2cdc [llvm-mca][BtVer2] teach how to identify false dependencies on partially written
registers.

The goal of this patch is to improve the throughput analysis in llvm-mca for the
case where instructions perform partial register writes.

On x86, partial register writes are quite difficult to model, mainly because
different processors tend to implement different register merging schemes in
hardware.

When the code contains partial register writes, the IPC (instructions per
cycles) estimated by llvm-mca tends to diverge quite significantly from the
observed IPC (using perf).

Modern AMD processors (at least, from Bulldozer onwards) don't rename partial
registers. Quoting Agner Fog's microarchitecture.pdf:
" The processor always keeps the different parts of an integer register together.
For example, AL and AH are not treated as independent by the out-of-order
execution mechanism. An instruction that writes to part of a register will
therefore have a false dependence on any previous write to the same register or
any part of it."

This patch is a first important step towards improving the analysis of partial
register updates. It changes the semantic of RegisterFile descriptors in
tablegen, and teaches llvm-mca how to identify false dependences in the presence
of partial register writes (for more details: see the new code comments in
include/Target/TargetSchedule.h - class RegisterFile).

This patch doesn't address the case where a write to a part of a register is
followed by a read from the whole register.  On Intel chips, high8 registers
(AH/BH/CH/DH)) can be stored in separate physical registers. However, a later
(dirty) read of the full register (example: AX/EAX) triggers a merge uOp, which
adds extra latency (and potentially affects the pipe usage).
This is a very interesting article on the subject with a very informative answer
from Peter Cordes:
https://stackoverflow.com/questions/45660139/how-exactly-do-partial-registers-on-haswell-skylake-perform-writing-al-seems-to

In future, the definition of RegisterFile can be extended with extra information
that may be used to identify delays caused by merge opcodes triggered by a dirty
read of a partial write.

Differential Revision: https://reviews.llvm.org/D49196

llvm-svn: 337123
2018-07-15 11:01:38 +00:00
Matt Davis 0e8402eccd [llvm-mca] Turn InstructionTables into a Stage.
Summary:
This patch converts the InstructionTables class into a subclass of mca::Stage.  This change allows us to use the Stage's inherited Listeners for event notifications.  This also allows us to create a simple pipeline for viewing the InstructionTables report.

I have been working on a follow on patch that should cleanup addView in InstructionTables.  Right now, addView adds the view to both the Listener list and Views list.  The follow-on patch addresses the fact that we don't really need two lists in this case.  That change is not specific to just InstructionTables, so it will be a separate patch. 

Reviewers: andreadb, courbet, RKSimon

Reviewed By: andreadb

Subscribers: tschuett, gbedwell, llvm-commits

Differential Revision: https://reviews.llvm.org/D49329

llvm-svn: 337113
2018-07-14 23:52:50 +00:00
Teresa Johnson b78c5d0602 Revert "[ThinLTO] Ensure we always select the same function copy to import"
This reverts commits r337050 and r337059. Caused failure in
reverse-iteration bot that needs more investigation.

llvm-svn: 337081
2018-07-14 01:45:49 +00:00
Matt Davis f6bcbf3d88 [llvm-mca] Remove unused InstRef formal from pre and post execute callbacks. NFC.
llvm-svn: 337077
2018-07-14 00:10:42 +00:00
Teresa Johnson d94c0594d9 [ThinLTO] Ensure we always select the same function copy to import
In order to always import the same copy of a linkonce function,
even when encountering it with different thresholds (a higher one then a
lower one), keep track of the summary we decided to import.
This ensures that the backend only gets a single definition to import
for each GUID, so that it doesn't need to choose one.

Move the largest threshold the GUID was considered for import into the
current module out of the ImportMap (which is part of a larger map
maintained across the whole index), and into a new map just maintained
for the current module we are computing imports for. This saves some
memory since we no longer have the thresholds maintained across the
whole index (and throughout the in-process backends when doing a normal
non-distributed ThinLTO build), at the cost of some additional
information being maintained for each invocation of ComputeImportForModule
(the selected summary pointer for each import).

There is an additional map lookup for each callee being considered for
importing, however, this was able to subsume a map lookup in the
Worklist iteration that invokes computeImportForFunction. We also are
able to avoid calling selectCallee if we already failed to import at the
same or higher threshold.

I compared the run time and peak memory for the SPEC2006 471.omnetpp
benchmark (running in-process ThinLTO backends), as well as for a large
internal benchmark with a distributed ThinLTO build (so just looking at
the thin link time/memory). Across a number of runs with and without
this change there was no significant change in the time and memory.

(I tried a few other variations of the change but they also didn't
improve time or peak memory).

Reviewers: davidxl

Subscribers: mehdi_amini, inglorion, llvm-commits

Differential Revision: https://reviews.llvm.org/D48670

llvm-svn: 337050
2018-07-13 21:35:51 +00:00
Joel Galenson 06e7e5798f [cfi-verify] Support AArch64.
This patch adds support for AArch64 to cfi-verify.

This required three changes to cfi-verify.  First, it generalizes checking if an instruction is a trap by adding a new isTrap flag to TableGen (and defining it for x86 and AArch64).  Second, the code that ensures that the operand register is not clobbered between the CFI check and the indirect call needs to allow a single dereference (in x86 this happens as part of the jump instruction).  Third, we needed to ensure that return instructions are not counted as indirect branches.  Technically, returns are indirect branches and can be covered by CFI, but LLVM's forward-edge CFI does not protect them, and x86 does not consider them, so we keep that behavior.

In addition, we had to improve AArch64's code to evaluate the branch target of a MCInst to handle calls where the destination is not the first operand (which it often is not).

Differential Revision: https://reviews.llvm.org/D48836

llvm-svn: 337007
2018-07-13 15:19:33 +00:00
Andrea Di Biagio 23fbe7cbb5 [llvm-mca] Improve a few debug prints. NFC
llvm-svn: 337003
2018-07-13 14:55:47 +00:00
Andrea Di Biagio 4335b3e239 [llvm-mca] Simplify the Pipeline constructor. NFC
llvm-svn: 336984
2018-07-13 09:31:02 +00:00
Andrea Di Biagio ef6b8a331f [llvm-mca] Removed unused arguments from methods in class Pipeline. NFC
llvm-svn: 336983
2018-07-13 09:27:34 +00:00
Dean Michael Berris 10141261e1 [XRay][compiler-rt] Add PID field to llvm-xray tool and add PID metadata record entry in FDR mode
Summary:
llvm-xray changes:
- account-mode - process-id  {...} shows after thread-id
- convert-mode - process {...} shows after thread
- parses FDR and basic mode pid entries
- Checks version number for FDR log parsing.

Basic logging changes:
- Update header version from 2 -> 3

FDR logging changes:
- Update header version from 2 -> 3
- in writeBufferPreamble, there is an additional PID Metadata record (after thread id record and tsc record)

Test cases changes:
- fdr-mode.cc, fdr-single-thread.cc, fdr-thread-order.cc modified to catch process id output in the log.

Reviewers: dberris

Reviewed By: dberris

Subscribers: hiraditya, llvm-commits, #sanitizers

Differential Revision: https://reviews.llvm.org/D49153

llvm-svn: 336974
2018-07-13 05:38:22 +00:00
Matt Davis 73dd5f9c08 [llvm-mca] Constify SourceMgr::hasNext. NFC.
llvm-svn: 336961
2018-07-12 23:19:30 +00:00
Matt Davis 3250899600 [llvm-mca] Add cycleBegin/cycleEnd callbacks to mca::Stage.
Summary:
This patch  clears up some of the semantics within the Stage class.  Now, preExecute
can be called multiple times per simulated cycle.  Previously preExecute was
only called once per cycle, and postExecute could have been called multiple
times.

Now, cycleStart/cycleEnd are called only once per simulated cycle.
preExecute/postExecute can be called multiple times per cycle.  This
occurs because multiple execution events can occur during a single cycle.

When stages are executed (Pipeline::runCycle), the postExecute hook will
be called only if all Stages return a success from their 'execute' callback.

Reviewers: andreadb, courbet, RKSimon

Reviewed By: andreadb

Subscribers: tschuett, gbedwell, llvm-commits

Differential Revision: https://reviews.llvm.org/D49250

llvm-svn: 336959
2018-07-12 22:59:53 +00:00
Bill Wendling 7bd9e94e38 [gold-plugin] Disable section ordering for relocatable links
Not all programs want section ordering when compiled with LTO.
In particular, the Linux kernel is very sensitive when it comes to linking, and
doesn't boot when each function is placed in its own sections.

Reviewed By: pcc

Differential Revision: https://reviews.llvm.org/D48756

llvm-svn: 336943
2018-07-12 20:35:58 +00:00
Stephen Hines e8c3c5fe5d Add --strip-all option back to llvm-strip.
Summary:
This option appears to have been dropped as part of the refactoring in
r331663. Unfortunately, if we want to use llvm-strip as a drop-in
replacement for strip, this option should still be available.

Reviewers: alexshap

Reviewed By: alexshap

Subscribers: meikeb, kongyi, chh, jakehehrlich, llvm-commits, pirama

Differential Revision: https://reviews.llvm.org/D49226

llvm-svn: 336921
2018-07-12 17:42:17 +00:00
Matt Davis 0906a7fc53 [llvm-mca] Simplify eventing by adding an onEvent templated method.
Summary:
This patch eliminates some redundancy in iterating across Listeners for the
Instruction and Stall HWEvents, by introducing a template onEvent routine.
This change was suggested by @courbet in https://reviews.llvm.org/D48576.  I
 hope that this patch addresses that suggestion appropriately.  I do like this
change better than what we had previously.


Reviewers: andreadb, courbet, RKSimon

Reviewed By: andreadb, courbet

Subscribers: javed.absar, tschuett, gbedwell, llvm-commits, courbet

Differential Revision: https://reviews.llvm.org/D48672

llvm-svn: 336916
2018-07-12 16:56:17 +00:00
Bill Wendling 9a1c773cfb Temporarily reverting.
llvm-svn: 336858
2018-07-11 21:47:55 +00:00
Bill Wendling e033b3afe3 gold: Add ability to toggle function/data sections
Some programs (e.g. Linux) aren't able to handle function/data sections when
LTO is used. Thus they need a way to disable it. That can be done with these
plugin options:

    -plugin-opt=-function-sections=0
    -plugin-opt=-data-sections=0

llvm-svn: 336838
2018-07-11 19:13:26 +00:00
Paul Semel 0f9ca2d960 Revert "[llvm-objdump] Add -demangle (-C) option"
This reverts commit 3a44ccd156e0edd2e89226f8ed63928e227900bb.
This reverts commit d5cfc836bb5552e20507d3612d13ff66ff9e36a0.

llvm-svn: 336829
2018-07-11 18:09:52 +00:00
Paul Semel bcf55ab95a [llvm-objdump] Add -demangle (-C) option
Differential Revision: https://reviews.llvm.org/D49043

llvm-svn: 336816
2018-07-11 15:25:39 +00:00
Andrea Di Biagio d2e2c053cf [llvm-mca] Use a different character to flag instructions with side-effects in the Instruction Info View. NFC
This makes easier to identify changes in the instruction info flags.  It also
helps spotting potential regressions similar to the one recently introduced at
r336728.

Using the same character to mark MayLoad/MayStore/HasSideEffects is problematic
for llvm-lit. When pattern matching substrings, llvm-lit consumes tabs and
spaces. A change in position of the flag marker may not trigger a test failure.

This patch only changes the character used for flag `hasSideEffects`. The reason
why I didn't touch other flags is because I want to avoid spamming the mailing
because of the massive diff due to the numerous tests affected by this change.

In future, each instruction flag should be associated with a different character
in the Instruction Info View.

llvm-svn: 336797
2018-07-11 12:44:44 +00:00
Paul Semel b98f504850 [llvm-readobj] Add -hex-dump (-x) option
Differential Revision: https://reviews.llvm.org/D48281

llvm-svn: 336782
2018-07-11 10:00:29 +00:00
Jonas Devlieghere e13e6dbe40 [MC] Add interface to finish pending labels.
When manually finishing the object writer in dsymutil, it's possible
that there are pending labels that haven't been resolved. This results
in an assertion when the assembler tries to fixup a label that doesn't
have an address yet.

Differential revision: https://reviews.llvm.org/D49131

llvm-svn: 336688
2018-07-10 15:32:17 +00:00
Paul Robinson c17c8bf749 Support -fdebug-prefix-map in llvm-mc. This is useful to omit the
debug compilation dir when compiling assembly files with -g.
Part of PR38050.

Patch by Siddhartha Bagaria!

Differential Revision: https://reviews.llvm.org/D48988

llvm-svn: 336680
2018-07-10 14:41:54 +00:00
Jonas Devlieghere 82dee6aca8 [dsymutil] Add support for outputting assembly
When implementing the DWARF accelerator tables in dsymutil I ran into an
assertion in the assembler. Debugging these kind of issues is a lot
easier when looking at the assembly instead of debugging the assembler
itself. Since it's only a matter of creating an AsmStreamer instead of a
MCObjectStreamer it made sense to turn this into a (hidden) dsymutil
feature.

Differential revision: https://reviews.llvm.org/D49079

llvm-svn: 336561
2018-07-09 16:58:48 +00:00
Andrea Di Biagio 8834779644 [llvm-mca] report an error if the assembly sequence contains an unsupported instruction.
This is a short-term fix for PR38093.
For now, we llvm::report_fatal_error if the instruction builder finds an
unsupported instruction in the instruction stream.

We need to revisit this fix once we start addressing PR38101.
Essentially, we need a better framework for error handling.

llvm-svn: 336543
2018-07-09 12:30:55 +00:00
Zachary Turner 648bebdc67 [PDB] One more fix for hasing GSI records.
The reference implementation uses a case-insensitive string
comparison for strings of equal length.  This will cause the
string "tEo" to compare less than "VUo".  However we were using
a case sensitive comparison, which would generate the opposite
outcome.  Switch to a case insensitive comparison.  Also, when
one of the strings contains non-ascii characters, fallback to
a straight memcmp.

The only way to really test this is with a DIA test.  Before this
patch, the test will fail (but succeed if link.exe is used instead
of lld-link).  After the patch, it succeeds even with lld-link.

llvm-svn: 336464
2018-07-06 21:01:42 +00:00
Matt Davis 362ea5f2c3 [llvm-mca] Add HardwareUnit and Context classes.
This patch moves the construction of the default backend from llvm-mca.cpp and
into mca::Context. The Context class is responsible for holding ownership of
the simulated hardware components. These components are subclasses of
HardwareUnit. Right now the HardwareUnit is pretty bare-bones, but eventually
we might want to add some common functionality across all hardware components,
such as isReady() or something similar.

I have a feeling this patch will probably need some updates, but it's a start.
One thing I am not particularly fond of is the rather large interface for
createDefaultPipeline. That convenience routine takes a rather large set of
inputs from the llvm-mca driver, where many of those inputs are generated via
command line options.

One item I think we might want to change is the separating of ownership of
hardware components (owned by the context) and the pipeline (which owns
Stages). In short, a Pipeline owns Stages, a Context (currently) owns hardware.
The Pipeline's Stages make use of the components, and thus there is a lifetime
dependency generated. The components must outlive the pipeline. We could solve
this by having the Context also own the Pipeline, and not return a
unique_ptr<Pipeline>. Now that I think about it, I like that idea more.

Differential Revision: https://reviews.llvm.org/D48691

llvm-svn: 336456
2018-07-06 18:03:14 +00:00
Alexander Shaposhnikov 42b5ef0269 [llvm-objcopy] Add support for static libraries
This diff adds support for handling static libraries 
to llvm-objcopy and llvm-strip.

Test plan: make check-all

Differential revision: https://reviews.llvm.org/D48413

llvm-svn: 336455
2018-07-06 17:51:03 +00:00
Vedant Kumar ba0c876597 [Debugify] Allow unsigned values narrower than their variables
Suppress the diagnostic for mis-sized dbg.values when a value operand is
narrower than the unsigned variable it describes. Assume that a debugger
would implicitly zero-extend these values.

llvm-svn: 336452
2018-07-06 17:32:40 +00:00
Andrea Di Biagio bb25e27f58 [llvm-mca] A write latency cannot be a negative value. NFC
llvm-svn: 336437
2018-07-06 13:46:10 +00:00
Jonas Devlieghere 7f19d0160b [dsymutil] Emit label at the begin of a CU
When emitting a CU, store the MCSymbol pointing to the beginning of the
CU. We'll need this information later when emitting the .debug_names
section (DWARF5 accelerator table).

llvm-svn: 336433
2018-07-06 12:49:54 +00:00
Andrea Di Biagio 61c52af9d9 [llvm-mca] improve the instruction issue logic implemented by the Scheduler.
This patch modifies the Scheduler heuristic used to select the next instruction
to issue to the pipelines.

The motivating example is test X86/BtVer2/add-sequence.s, for which llvm-mca
wrongly reported an estimated IPC of 1.50. According to perf, the actual IPC for
that test should have been ~2.00.
It turns out that an IPC of 2.00 for test add-sequence.s cannot possibly be
predicted by a Scheduler that only prioritizes instructions based on their
"age". A similar issue also affected test X86/BtVer2/dependent-pmuld-paddd.s,
for which llvm-mca wrongly estimated an IPC of 0.84 instead of an IPC of 1.00.

Instructions in the ReadyQueue are now ranked based on two factors:
 - The "age" of an instruction.
 - The number of unique users of writes associated with an instruction.

The new logic still prioritizes older instructions over younger instructions to
minimize the pressure on the reorder buffer. However, the number of users of an
instruction now also affects the overall rank. This potentially increases the
ability of the Scheduler to extract instruction level parallelism.  This patch
fixes the problem with the wrong IPC reported for test add-sequence.s and test
dependent-pmuld-paddd.s.

llvm-svn: 336420
2018-07-06 08:08:30 +00:00