Try again with an up-to-date version of D69471 (99317124 was a stale
revision).
---
Revise the coverage mapping format to reduce binary size by:
1. Naming function records and marking them `linkonce_odr`, and
2. Compressing filenames.
This shrinks the size of llc's coverage segment by 82% (334MB -> 62MB)
and speeds up end-to-end single-threaded report generation by 10%. For
reference the compressed name data in llc is 81MB (__llvm_prf_names).
Rationale for changes to the format:
- With the current format, most coverage function records are discarded.
E.g., more than 97% of the records in llc are *duplicate* placeholders
for functions visible-but-not-used in TUs. Placeholders *are* used to
show under-covered functions, but duplicate placeholders waste space.
- We reached general consensus about giving (1) a try at the 2017 code
coverage BoF [1]. The thinking was that using `linkonce_odr` to merge
duplicates is simpler than alternatives like teaching build systems
about a coverage-aware database/module/etc on the side.
- Revising the format is expensive due to the backwards compatibility
requirement, so we might as well compress filenames while we're at it.
This shrinks the encoded filenames in llc by 86% (12MB -> 1.6MB).
See CoverageMappingFormat.rst for the details on what exactly has
changed.
Fixes PR34533 [2], hopefully.
[1] http://lists.llvm.org/pipermail/llvm-dev/2017-October/118428.html
[2] https://bugs.llvm.org/show_bug.cgi?id=34533
Differential Revision: https://reviews.llvm.org/D69471
Revise the coverage mapping format to reduce binary size by:
1. Naming function records and marking them `linkonce_odr`, and
2. Compressing filenames.
This shrinks the size of llc's coverage segment by 82% (334MB -> 62MB)
and speeds up end-to-end single-threaded report generation by 10%. For
reference the compressed name data in llc is 81MB (__llvm_prf_names).
Rationale for changes to the format:
- With the current format, most coverage function records are discarded.
E.g., more than 97% of the records in llc are *duplicate* placeholders
for functions visible-but-not-used in TUs. Placeholders *are* used to
show under-covered functions, but duplicate placeholders waste space.
- We reached general consensus about giving (1) a try at the 2017 code
coverage BoF [1]. The thinking was that using `linkonce_odr` to merge
duplicates is simpler than alternatives like teaching build systems
about a coverage-aware database/module/etc on the side.
- Revising the format is expensive due to the backwards compatibility
requirement, so we might as well compress filenames while we're at it.
This shrinks the encoded filenames in llc by 86% (12MB -> 1.6MB).
See CoverageMappingFormat.rst for the details on what exactly has
changed.
Fixes PR34533 [2], hopefully.
[1] http://lists.llvm.org/pipermail/llvm-dev/2017-October/118428.html
[2] https://bugs.llvm.org/show_bug.cgi?id=34533
Differential Revision: https://reviews.llvm.org/D69471
Revise the coverage mapping format to reduce binary size by:
1. Naming function records and marking them `linkonce_odr`, and
2. Compressing filenames.
This shrinks the size of llc's coverage segment by 82% (334MB -> 62MB)
and speeds up end-to-end single-threaded report generation by 10%. For
reference the compressed name data in llc is 81MB (__llvm_prf_names).
Rationale for changes to the format:
- With the current format, most coverage function records are discarded.
E.g., more than 97% of the records in llc are *duplicate* placeholders
for functions visible-but-not-used in TUs. Placeholders *are* used to
show under-covered functions, but duplicate placeholders waste space.
- We reached general consensus about giving (1) a try at the 2017 code
coverage BoF [1]. The thinking was that using `linkonce_odr` to merge
duplicates is simpler than alternatives like teaching build systems
about a coverage-aware database/module/etc on the side.
- Revising the format is expensive due to the backwards compatibility
requirement, so we might as well compress filenames while we're at it.
This shrinks the encoded filenames in llc by 86% (12MB -> 1.6MB).
See CoverageMappingFormat.rst for the details on what exactly has
changed.
Fixes PR34533 [2], hopefully.
[1] http://lists.llvm.org/pipermail/llvm-dev/2017-October/118428.html
[2] https://bugs.llvm.org/show_bug.cgi?id=34533
Differential Revision: https://reviews.llvm.org/D69471
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
In the coverage report, the line and count columns have been swapped to make it more readable.
A follow-up commit in compiler-rt is needed
Differential Revision: https://reviews.llvm.org/D23281
llvm-svn: 278152
This enables users to export coverage information as portable JSON for use by
analysis tools and storage in document based databases.
The export sub-command is invoked just like the others:
llvm-cov export -instr-profile path/to/foo.profdata path/to/foo.binary
The resulting JSON contains a list of files and functions. Every file object
contains a list of segments, expansions, and a summary of the file's region,
function, and line coverage. Every function object contains the function's name
and regions. There is also a total summary for the entire object file.
Changes since the initial commit (r276813):
- Fixed the regexes in the tests to handle Windows filepaths.
Patch by Eddie Hurtig!
Differential Revision: https://reviews.llvm.org/D22651
llvm-svn: 276818
This enables users to export coverage information as portable JSON for use by
analysis tools and storage in document based databases.
The export sub-command is invoked just like the others:
llvm-cov export -instr-profile path/to/foo.profdata path/to/foo.binary
The resulting JSON contains a list of files and functions. Every file object
contains a list of segments, expansions, and a summary of the file's region,
function, and line coverage. Every function object contains the function's name
and regions. There is also a total summary for the entire object file.
Patch by Eddie Hurtig!
Differential Revision: https://reviews.llvm.org/D22651
llvm-svn: 276813
This makes the reader check the endianness of the object file its
given and behave appropriately. For the test I dug up a really old
linker and created a ppc-apple-darwin file for llvm-cov to read.
llvm-svn: 232422
This still doesn't actually work correctly for big endian input files,
but since these tests all use little endian input files they don't
actually fail. I'll be committing a real fix for big endian soon, but
I don't have proper tests for it yet.
llvm-svn: 232354
This code was casting regions of a memory buffer to a couple of
different structs. This is wrong in a few ways:
1. It breaks aliasing rules.
2. If the buffer isn't aligned, it hits undefined behaviour.
3. It completely ignores endianness differences.
4. The structs being defined for this aren't specifying their padding
properly, so this doesn't even represent the data properly on some
platforms.
This commit is mostly NFC, except that it fixes reading coverage for
32 bit binaries as a side effect of getting rid of the mispadded
structs. I've included a test for that.
I've also baked in that we only handle little endian more explicitly,
since that was true in practice already. I'll fix this to handle
endianness properly in a followup commit.
llvm-svn: 232346
Vedant Kumar