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
Emit a gap region beginning where the switch body begins. This sets line
execution counts in the areas between non-overlapping cases to 0.
This also removes some special handling of the first case in a switch:
these are now treated like any other case.
This does not resolve an outstanding issue with case statement regions
that do not end when a region is terminated. But it should address
llvm.org/PR44011.
Differential Revision: https://reviews.llvm.org/D70571
This reverts commit 9d4806a387.
There seem to be bugs in llvm-cov --path-equivalence that are causing
Chromium problems. Revert this until they are understood or fixed.
This reverts r374324 (git commit 62808631ac)
I changed the test to not rely on finding the sequence "clang, test,
CoverageMapping" in the CWD used to run the test. Instead it makes its
own internal directory hierarchy of foo/bar/baz and looks for that.
llvm-svn: 374403
This reverts commit f6777964bd.
Because the absolute path check relies on temporary path containing
"clang", "test" and "CoverageMapping" as a subsequence, which is not
necessarily true on all systems(breaks internal integrates). Wanted to
fix it by checking for a leading "/" instead, but then noticed that it
would break windows tests, so leaving it to the author instead.
llvm-svn: 374324
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
There is no reason to emit coverage mappings for artificial statements
contained within defaulted methods, as these statements are not visible
to users.
Only emit a mapping for the body of the defaulted method (clang treats
the text of the "default" keyword as the body when reporting locations).
This allows users to see how often the default method is called, but
trims down the coverage mapping by skipping visitation of the children
of the method.
The immediate motivation for this change is that the lexer's
getPreciseTokenLocEnd API cannot return the correct location when given
an artificial statement (with a somewhat made-up location) as an input.
Test by Orivej Desh!
Fixes llvm.org/PR39822.
llvm-svn: 347803
popRegions used to assume that the start location of a region can't be
nested deeper than the end location, which is not always true.
Patch by Orivej Desh!
Differential Revision: https://reviews.llvm.org/D53244
llvm-svn: 347262
A deferred region should end before the start of a label, and should not
extend to the start of the label sub-statement.
Fixes llvm.org/PR35867.
llvm-svn: 333715
Discard the last uncompleted deferred region in a decl, if one exists.
This prevents lines at the end of a function containing only whitespace
or closing braces from being marked as uncovered, if they follow a
region terminator (return/break/etc).
The previous behavior was to heuristically complete deferred regions at
the end of a decl. In practice this ended up being too brittle for too
little gain. Users would complain that there was no way to reach full
code coverage because whitespace at the end of a function would be
marked uncovered.
rdar://40238228
Differential Revision: https://reviews.llvm.org/D46918
llvm-svn: 333609
This is similar to the LLVM change https://reviews.llvm.org/D46290.
We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.
Patch produced by
for i in $(git grep -l '\@brief'); do perl -pi -e 's/\@brief //g' $i & done
for i in $(git grep -l '\\brief'); do perl -pi -e 's/\\brief //g' $i & done
Differential Revision: https://reviews.llvm.org/D46320
llvm-svn: 331834
When a '>>' token is split into two '>' tokens (in C++11 onwards), or (as an
extension) when we do the same for other tokens starting with a '>', we can't
just use a location pointing to the first '>' as the location of the split
token, because that would result in our miscomputing the length and spelling
for the token. As a consequence, for example, a refactoring replacing 'A<X>'
with something else would sometimes replace one character too many, and
similarly diagnostics highlighting a template-id source range would highlight
one character too many.
Fix this by creating an expansion range covering the first character of the
'>>' token, whose spelling is '>'. For this to work, we generalize the
expansion range of a macro FileID to be either a token range (the common case)
or a character range (used in this new case).
llvm-svn: 331155
Found via codespell -q 3 -I ../clang-whitelist.txt
Where whitelist consists of:
archtype
cas
classs
checkk
compres
definit
frome
iff
inteval
ith
lod
methode
nd
optin
ot
pres
statics
te
thru
Patch by luzpaz! (This is a subset of D44188 that applies cleanly with a few
files that have dubious fixes reverted.)
Differential revision: https://reviews.llvm.org/D44188
llvm-svn: 329399
When parsing C++ type construction expressions with list initialization,
forward the locations of the braces to Sema.
Without these locations, the code coverage pass crashes on the given test
case, because the pass relies on getLocEnd() returning a valid location.
Here is what this patch does in more detail:
- Forwards init-list brace locations to Sema (ParseExprCXX),
- Builds an InitializationKind with these locations (SemaExprCXX), and
- Uses these locations for constructor initialization (SemaInit).
The remaining changes fall out of introducing a new overload for
creating direct-list InitializationKinds.
Testing: check-clang, and a stage2 coverage-enabled build of clang with
asserts enabled.
Differential Revision: https://reviews.llvm.org/D41921
llvm-svn: 322729
Emit a gap area starting after the r-paren location and ending at the
start of the body for the braces-optional statements (for, for-each,
while, etc). The count for the gap area equal to the body's count. This
extends the fix in r317758.
Fixes PR35387, rdar://35570345
Testing: stage2 coverage-enabled build of clang, check-clang
llvm-svn: 319373
There are some limitations with emitting regions in macro expansions
because we don't gather file IDs within the expansions. Fix the check
that prevents us from emitting deferred regions in expansions to make an
exception for headers, which is something we can handle.
rdar://35373009
llvm-svn: 317760
The area immediately after a terminated region in the function top-level
should have the same count as the label it precedes.
This solves another problem with wrapped segments. Consider:
1| a:
2| return 0;
3| b:
4| return 1;
Without a gap area starting after the first return, the wrapped segment
from line 2 would make it look like line 3 is executed, when it's not.
rdar://35373009
llvm-svn: 317759
The area immediately after the closing right-paren of an if condition
should have a count equal to the 'then' block's count. Use a gap region
to set this count, so that region highlighting for the 'then' block
remains precise.
This solves a problem we have with wrapped segments. Consider:
1| if (false)
2| foo();
Without a gap area starting after the condition, the wrapped segment
from line 1 would make it look like line 2 is executed, when it's not.
rdar://35373009
llvm-svn: 317758
A trailing deferred region isn't necessary in a function that ends with
this pattern:
...
else {
...
return;
}
Special-case this pattern so that the closing curly brace of the
function isn't marked as uncovered. This issue came up in PR34962.
llvm-svn: 315982
This makes it possible to view sub-line region counts for the l.h.s of
&& and || expressions in coverage reports.
It also fixes PR33465, which shows an example of incorrect coverage
output for an assignment statement containing '||'.
llvm-svn: 315979
As a special case, throw away deferred regions for trailing returns.
This allows the closing curly brace to have a count, and is less
distracting.
llvm-svn: 313603
This patch teaches the preprocessor to report more precise source ranges for
code that is skipped due to conditional directives.
The new behavior includes the '#' from the opening directive and the full text
of the line containing the closing directive in the skipped area. This matches
up clang's behavior (we don't IRGen the code between the closing "endif" and
the end of a line).
This also affects the code coverage implementation. See llvm.org/PR34166 (this
also happens to be rdar://problem/23224058).
The old behavior (report the end of the skipped range as the end
location of the 'endif' token) is preserved for indexing clients.
Differential Revision: https://reviews.llvm.org/D36642
llvm-svn: 312947
The current coverage implementation doesn't handle region termination
very precisely. Take for example an `if' statement with a `return':
void f() {
if (true) {
return; // The `if' body's region is terminated here.
}
// This line gets the same coverage as the `if' condition.
}
If the function `f' is called, the line containing the comment will be
marked as having executed once, which is not correct.
The solution here is to create a deferred region after terminating a
region. The deferred region is completed once the start location of the
next statement is known, and is then pushed onto the region stack.
In the cases where it's not possible to complete a deferred region, it
can safely be dropped.
Testing: lit test updates, a stage2 coverage-enabled build of clang
This is a reapplication but there are no changes from the original commit.
With D36813, the segment builder in llvm will be able to handle deferred
regions correctly.
llvm-svn: 312818
The code after a noreturn call doesn't execute.
The pattern in the testcase is pretty common in LLVM (a switch with
a default case that calls llvm_unreachable).
The original version of this patch was reverted in r309995 due to a
crash. This version includes a fix for that crash (testcase in
test/CoverageMapping/md.cpp).
Differential Revision: https://reviews.llvm.org/D36250
llvm-svn: 310406
This reverts commit r310010. I don't think there's anything wrong with
this commit, but it's causing clang to generate output that llvm-cov
doesn't do a good job with and the fix isn't immediately clear.
See Eli's comment in D36250 for more context.
I'm reverting the clang change so the coverage bot can revert back to
producing sensible output, and to give myself some time to investigate
what went wrong in llvm.
llvm-svn: 310154
The current coverage implementation doesn't handle region termination
very precisely. Take for example an `if' statement with a `return':
void f() {
if (true) {
return; // The `if' body's region is terminated here.
}
// This line gets the same coverage as the `if' condition.
}
If the function `f' is called, the line containing the comment will be
marked as having executed once, which is not correct.
The solution here is to create a deferred region after terminating a
region. The deferred region is completed once the start location of the
next statement is known, and is then pushed onto the region stack.
In the cases where it's not possible to complete a deferred region, it
can safely be dropped.
Testing: lit test updates, a stage2 coverage-enabled build of clang
llvm-svn: 310010
The code after a noreturn call doesn't execute.
The pattern in the testcase is pretty common in LLVM (a switch with
a default case that calls llvm_unreachable).
Differential Revision: https://reviews.llvm.org/D36250
llvm-svn: 309995
We never overwrite the end location of a region, so we would end up with
an overly large region when we reused the switch's region.
It's possible this code will be substantially rewritten in the near
future to deal with fallthrough more accurately, but this seems like
an improvement on its own for now.
Differential Revision: https://reviews.llvm.org/D34801
llvm-svn: 309901
Vedant Kumar