Summary:
[llvm-exegesis][RFC] Automatic Measurement of Instruction Latency/Uops
This is the code corresponding to the RFC "llvm-exegesis Automatic Measurement of Instruction Latency/Uops".
The RFC is available on the LLVM mailing lists as well as the following document
for easier reading:
https://docs.google.com/document/d/1QidaJMJUyQdRrFKD66vE1_N55whe0coQ3h1GpFzz27M/edit?usp=sharing
Subscribers: mgorny, gchatelet, orwant, llvm-commits
Differential Revision: https://reviews.llvm.org/D44519
llvm-svn: 329156
Before this patch, the "BackendStatistics" view was responsible for printing the
register file usage (as well as many other statistics).
Now users can enable register file usage statistics using the command line flag
`-register-file-stats`. By default, the tool doesn't print register file
statistics.
llvm-svn: 329083
When running dsymutil as part of your build system, it can be desirable
for warnings to be part of the end product, rather than just being
emitted to the output stream. This patch upstreams that functionality.
Differential revision: https://reviews.llvm.org/D44639
llvm-svn: 328965
Document that flag -resource-pressure can be used to enable/disable the resource
pressure view. This change should have been part of r328305.
llvm-svn: 328492
The goal of this patch is to address most of PR36874. To fully fix PR36874 we
need to split the "InstructionInfo" view from the "SummaryView". That would make
easy to check the latency and rthroughput as well.
The patch reuses all the logic from ResourcePressureView to print out the
"instruction tables".
We have an entry for every instruction in the input sequence. Each entry reports
the theoretical resource pressure distribution. Resource pressure is uniformly
distributed across all the processor resource units of a group.
At the moment, the backend pipeline is not configurable, so the only way to fix
this is by creating a different driver that simply sends instruction events to
the resource pressure view. That means, we don't use the Backend interface.
Instead, it is simpler to just have a different code-path for when flag
-instruction-tables is specified.
Once Clement addresses bug 36663, then we can port the "instruction tables"
logic into a stage of our configurable pipeline.
Updated the BtVer2 test cases (thanks Simon for the help). Now we pass flag
-instruction-tables to each modified test.
Differential Revision: https://reviews.llvm.org/D44839
llvm-svn: 328487
llvm-mca is an LLVM based performance analysis tool that can be used to
statically measure the performance of code, and to help triage potential
problems with target scheduling models.
llvm-mca uses information which is already available in LLVM (e.g. scheduling
models) to statically measure the performance of machine code in a specific cpu.
Performance is measured in terms of throughput as well as processor resource
consumption. The tool currently works for processors with an out-of-order
backend, for which there is a scheduling model available in LLVM.
The main goal of this tool is not just to predict the performance of the code
when run on the target, but also help with diagnosing potential performance
issues.
Given an assembly code sequence, llvm-mca estimates the IPC (instructions per
cycle), as well as hardware resources pressure. The analysis and reporting style
were mostly inspired by the IACA tool from Intel.
This patch is related to the RFC on llvm-dev visible at this link:
http://lists.llvm.org/pipermail/llvm-dev/2018-March/121490.html
Differential Revision: https://reviews.llvm.org/D43951
llvm-svn: 326998
This commit attempts to re-land the r324480 which was reverted in
r324493 because it broke the Windows bots. For now I disabled the two
update tests on Windows until I'm able to debug this.
Differential revision: https://reviews.llvm.org/D42880
llvm-svn: 324592
Now that dsymutil can generate accelerator tables, we can upstream the
update logic that, as the name implies, updates the accelerator tables
in an existing dSYM bundle. In combination with `-minimize` this can be
used to remove redundant .debug_(inlines|pubtypes|pubnames).
Differential revision: https://reviews.llvm.org/D42880
llvm-svn: 324480
Passing -minimize to dsymutil prevents the emission of .debug_inlines,
.debug_pubnames, and .debug_pubtypes in favor of the Apple accelerator
tables.
The actual check in the DWARF linker was added in r323655. This patch
simply enables it.
Differential revision: https://reviews.llvm.org/D42688
llvm-svn: 323812
Change symbol values in the stack_size section from being 8 bytes, to being a target dependent size.
Differential Revision: https://reviews.llvm.org/D42108
llvm-svn: 322619
Summary:
That allows to get the same data as produced by "llvm-cov report",
but in JSON format, which is better for further processing by end users.
Reviewers: vsk
Reviewed By: vsk
Differential Revision: https://reviews.llvm.org/D41085
llvm-svn: 320435
Re applying after fixing issues in the diff, sorry for any painful conflicts/merges!
Original RFC: http://lists.llvm.org/pipermail/llvm-dev/2017-August/117028.html
This change adds a '.stack-size' section containing metadata on function stack sizes to output ELF files behind the new -stack-size-section flag. The section contains pairs of function symbol references (8 byte) and stack sizes (unsigned LEB128).
The contents of this section can be used to measure changes to stack sizes between different versions of the compiler or a source base. The advantage of having a section is that we can extract this information when examining binaries that we didn't build, and it allows users and tools easy access to that information just by referencing the binary.
There is a follow up change to add an option to clang.
Thanks.
Reviewers: hfinkel, MatzeB
Reviewed By: MatzeB
Subscribers: thegameg, asb, llvm-commits
Differential Revision: https://reviews.llvm.org/D39788
llvm-svn: 319430
Summary:
Original RFC: http://lists.llvm.org/pipermail/llvm-dev/2017-August/117028.html
I wasn't sure who to put as reviewers, so please add/remove people as appropriate.
This change adds a '.stack-size' section containing metadata on function stack sizes to output ELF files behind the new -stack-size-section flag. The section contains pairs of function symbol references (8 byte) and stack sizes (unsigned LEB128).
The contents of this section can be used to measure changes to stack sizes between different versions of the compiler or a source base. The advantage of having a section is that we can extract this information when examining binaries that we didn't build, and it allows users and tools easy access to that information just by referencing the binary.
There is a follow up change to add an option to clang.
Thanks.
Reviewers: hfinkel, MatzeB
Reviewed By: MatzeB
Subscribers: thegameg, asb, llvm-commits
Differential Revision: https://reviews.llvm.org/D39788
llvm-svn: 319423
Summary:
This makes it very easy to test files that only differ in a constant
value somewhere in the test case.
Reviewers: jlebar, hfinkel, chandlerc, probinson
Reviewed By: probinson
Subscribers: probinson, llvm-commits
Differential Revision: https://reviews.llvm.org/D39629
llvm-svn: 317572
It is currently not possible to build the documentation with cmake and
the same version of Sphinx (1.5.1) used to generate the public facing
documentation on llvm.org. When code blocks cannot be parsed by
Pygments, it generates a warning which is treated as an error.
In addition to being annoying and confusing for developers, this
needlessly increases the bar for newcomers that want to get involved.
This patch removes the language specifier from the affected block. The
result is the same as when parsing fails: the block are not highlighted.
llvm-svn: 317472
This refers to a temporary path that can be shared across all tests,
identified by a particular label. This can be used for things like
caches.
At the moment, the character set for the LABEL is limited to C
identifier characters, plus '-', '+', '=', and '.'. This is the same
set of characters currently allowed in REQUIRES clause identifiers.
llvm-svn: 315697
Minor doc update that the FileCheck matcher supports POSIX ERE.
It also fixes a minor issue in the regexp describing a variable
name: underscores are allowed too.
Differential Revision: https://reviews.llvm.org/D38787
llvm-svn: 315679
At the last LLVM dev meeting we had a debug info for optimized code
BoF session. In that session I presented some graphs that showed how
the quality of the debug info produced by LLVM changed over the last
couple of years. This is a cleaned up version of the patch I used to
collect the this data. It is implemented as an extension of
llvm-dwarfdump, adding a new --statistics option. The intended
use-case is to automatically run this on the debug info produced by,
e.g., our bots, to identify eyebrow-raising changes or regressions
introduced by new transformations that we could act on.
In the current form, two kinds of data are being collected:
- The number of variables that have a debug location versus the number
of variables in total (this takes into account inlined instances of
the same function, so if a variable is completely missing form only
one instance it will be found).
- The PC range covered by variable location descriptions versus the PC
range of all variables' containing lexical scopes.
The output format is versioned and extensible, so I'm looking forward
to both bug fixes and ideas for other data that would be interesting
to track.
Differential Revision: https://reviews.llvm.org/D36627
llvm-svn: 315101
Summary: Add a -name-whitelist option, which behaves in the same way as -name, but it reads in multiple function names from the given input file(s).
Reviewers: vsk
Reviewed By: vsk
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D37111
llvm-svn: 312227
Summary:
This patch adds the -path-equivalence option (example: llvm-cov show -path-equivalence=/origin/path,/local/path) which maps the source code path from one machine to another when using `llvm-cov show`. This is similar to the -filename-equivalence option, but doesn't require you to specify all the source files on the command line.
This allows you to generate the coverage data on one machine (e.g. in a CI system), and then use llvm-cov on another machine where you have the same code base on a different path.
Reviewers: vsk
Reviewed By: vsk
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D36391
llvm-svn: 310827
The coverage tool needs to know which slice to look at when it's handed
a universal binary. Some projects need to look at aggregate coverage
reports for a variety of slices in different binaries: this patch adds
support for these kinds of projects to llvm-cov.
rdar://problem/33579007
llvm-svn: 309747
Debugging LIT scripts can be rather painful, as LIT directly does not
specify which line has failed.
Rather, FileCheck is expected to report the failing location, but it can
be often ambiguous if multiple commands are tested against the same
prefix. This change adds a -vv option, which echoes all output.
Then detecting the error becomes straightforward: last printed line is
the failing one.
Of course, it could be desired to try to get failing line number
directly from bash, but it involves excessive hacks on older bash
versions (cf.
https://stackoverflow.com/questions/24398691/how-to-get-the-real-line-number-of-a-failing-bash-command)
Differential Revision: https://reviews.llvm.org/D35330
llvm-svn: 307938
When an output directory is specified, llvm-cov spawns some threads to
speed up the process of writing out file reports. Add an option which
allows users to control how many threads llvm-cov uses.
A CommandGuide.rst update + test is included.
llvm-svn: 307609
This is especially useful when lit is invoked indirectly by the build
system, and additional arguments can not be easily specified.
Differential Revision: https://reviews.llvm.org/D35091
llvm-svn: 307339
This patch adds the value profile support to profile the size parameter of
memory intrinsic calls: memcpy, memcmp, and memmov.
Differential Revision: http://reviews.llvm.org/D28965
llvm-svn: 297897
If `--enable-var-scope` is in effect, variables with names that
start with `$` are considered to be global. All other variables are
local. All local variables get undefined at the beginning of each
CHECK-LABEL block. Global variables are not affected by CHECK-LABEL.
This makes it easier to ensure that individual tests are not affected
by variables set in preceding tests.
Differential Revision: https://reviews.llvm.org/D30749
llvm-svn: 297396
Clement Courbet