This fixes support for merging profiles which broke as a consequence
of e50a38840d. The issue was missing
adjustment in merge logic to account for the binary IDs which are
now included in the raw profile just after header.
In addition, this change also:
* Includes the version in module signature that's used for merging
to avoid accidental attempts to merge incompatible profiles.
* Moves the binary IDs size field after version field in the header
as was suggested in the review.
Differential Revision: https://reviews.llvm.org/D107143
This fixes support for merging profiles which broke as a consequence
of e50a38840d. The issue was missing
adjustment in merge logic to account for the binary IDs which are
now included in the raw profile just after header.
In addition, this change also:
* Includes the version in module signature that's used for merging
to avoid accidental attempts to merge incompatible profiles.
* Moves the binary IDs size field after version field in the header
as was suggested in the review.
Differential Revision: https://reviews.llvm.org/D107143
Add support for continuously syncing profile counter updates to a file.
The motivation for this is that programs do not always exit cleanly. On
iOS, for example, programs are usually killed via a signal from the OS.
Running atexit() handlers after catching a signal is unreliable, so some
method for progressively writing out profile data is necessary.
The approach taken here is to mmap() the `__llvm_prf_cnts` section onto
a raw profile. To do this, the linker must page-align the counter and
data sections, and the runtime must ensure that counters are mapped to a
page-aligned offset within a raw profile.
Continuous mode is (for the moment) incompatible with the online merging
mode. This limitation is lifted in https://reviews.llvm.org/D69586.
Continuous mode is also (for the moment) incompatible with value
profiling, as I'm not sure whether there is interest in this and the
implementation may be tricky.
As I have not been able to test extensively on non-Darwin platforms,
only Darwin support is included for the moment. However, continuous mode
may "just work" without modification on Linux and some UNIX-likes. AIUI
the default value for the GNU linker's `--section-alignment` flag is set
to the page size on many systems. This appears to be true for LLD as
well, as its `no_nmagic` option is on by default. Continuous mode will
not "just work" on Fuchsia or Windows, as it's not possible to mmap() a
section on these platforms. There is a proposal to add a layer of
indirection to the profile instrumentation to support these platforms.
rdar://54210980
Differential Revision: https://reviews.llvm.org/D68351
I removed this test to unblock the ARM bots while looking into failures
(r374915), and am reinstating it now with a fix.
I believe the problem was that counter ptr address I used,
'\0\0\6\0\1\0\0\1', set the high bits of the pointer, not the low bits
like I wanted. On x86_64 this superficially looks like it tests r370826,
but it doesn't, as it would have been caught before r370826. However, on
ARM (or, 32-bit hosts more generally), I suspect the high bits were
cleared, and you get a 'valid' profile.
I verified that setting the *low* bits of the pointer does trigger the
new condition:
-// Note: The CounterPtr here is off-by-one. This should trigger a malformed profile error.
-RUN: printf '\0\0\6\0\1\0\0\1' >> %t.profraw
+// Note: The CounterPtr here is off-by-one.
+//
+// Octal '\11' is 9 in decimal: this should push CounterOffset to 1. As there are two counters,
+// the profile reader should error out.
+RUN: printf '\11\0\6\0\1\0\0\0' >> %t.profraw
This reverts commit c7cf5b3e4b918c9769fd760f28485b8d943ed968.
llvm-svn: 374927
There are a number arm bots failing after r374617 landed, and I'm not
sure why. It looks a bit like the error message llvm-profdata is
expected to print to stderr isn't flushed.
Weaken the test in an attempt to appease the arm bots: if this doesn't
work, that means that llvm-profdata is actually *not failing*, and that
will be a clear indication that some logic error is actually happening.
http://lab.llvm.org:8011/builders/clang-cmake-armv7-global-isel/builds/5604/
llvm-svn: 374792
The check needs to validate a counter offset before performing pointer
arithmetic with the (potentially corrupt) offset.
Found by UBSan's pointer overflow check.
rdar://54843625
Differential Revision: https://reviews.llvm.org/D66979
llvm-svn: 370826
Petr Hosek