Summary:
r262157 added ELF-specific logic to put a comdat on the __profc_*
globals created for available_externally functions. We should be able to
generalize that logic to all object file formats that support comdats,
i.e. everything other than MachO. This fixes duplicate symbol errors,
since on COFF, linkonce_odr doesn't make the symbol weak.
Fixes PR38251.
Reviewers: davidxl, xur
Subscribers: hiraditya, dmajor, llvm-commits, aheejin
Differential Revision: https://reviews.llvm.org/D49882
llvm-svn: 338082
The API verification tool tapi has difficulty processing frameworks
which enable code coverage, but which have no code. The profile lowering
pass does not emit the runtime hook in this case because no counters are
lowered.
While the hook is not needed for program correctness (the profile
runtime doesn't have to be linked in), it's needed to allow tapi to
validate the exported symbol set of instrumented binaries.
It was not possible to add a workaround in tapi for empty binaries due
to an architectural issue: tapi generates its expected symbol set before
it inspects a binary. Changing that model has a higher cost than simply
forcing llvm to always emit the runtime hook.
rdar://36076904
Differential Revision: https://reviews.llvm.org/D43794
llvm-svn: 326350
Doing so breaks compilation of the following C program
(under -fprofile-instr-generate):
__attribute__((always_inline)) inline int foo() { return 0; }
int main() { return foo(); }
At link time, we fail because taking the address of an
available_externally function creates an undefined external reference,
which the TU cannot provide.
Emitting the function definition into the object file at all appears to
be a violation of the langref: "Globals with 'available_externally'
linkage are never emitted into the object file corresponding to the LLVM
module."
Differential Revision: https://reviews.llvm.org/D34134
llvm-svn: 305327
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
This reverts 295092 (re-applies 295084), with a fix for dangling
references from the array of coverage names passed down from frontends.
I missed this in my initial testing because I only checked test/Profile,
and not test/CoverageMapping as well.
Original commit message:
The profile name variables passed to counter increment intrinsics are dead
after we emit the finalized name data in __llvm_prf_nm. However, we neglect to
erase these name variables. This causes huge size increases in the
__TEXT,__const section as well as slowdowns when linker dead stripping is
disabled. Some affected projects are so massive that they fail to link on
Darwin, because only the small code model is supported.
Fix the issue by throwing away the name constants as soon as we're done with
them.
Differential Revision: https://reviews.llvm.org/D29921
llvm-svn: 295099
The profile name variables passed to counter increment intrinsics are
dead after we emit the finalized name data in __llvm_prf_nm. However, we
neglect to erase these name variables. This causes huge size increases
in the __TEXT,__const section as well as slowdowns when linker dead
stripping is disabled. Some affected projects are so massive that they
fail to link on Darwin, because only the small code model is supported.
Fix the issue by throwing away the name constants as soon as we're done
with them.
Differential Revision: https://reviews.llvm.org/D29921
llvm-svn: 295084
On some architectures (s390x, ppc64, sparc64, mips), C-level int is passed
as i32 signext instead of plain i32. Likewise, unsigned int may be passed
as i32, i32 signext, or i32 zeroext depending on the platform. Mark
__llvm_profile_instrument_target properly (its last parameter is unsigned
int).
This (together with the clang change) makes compiler-rt profile testsuite pass
on s390x.
Differential Revision: http://reviews.llvm.org/D21736
llvm-svn: 287534
On Darwin, marking a section as "regular,live_support" means that a
symbol in the section should only be kept live if it has a reference to
something that is live. Otherwise, the linker is free to dead-strip it.
Turn this functionality on for the __llvm_prf_data section.
This means that counters and data associated with dead functions will be
removed from dead-stripped binaries. This will result in smaller
profiles and binaries, and should speed up profile collection.
Tested with check-profile, llvm-lit test/tools/llvm-{cov,profdata}, and
check-llvm.
Differential Revision: https://reviews.llvm.org/D25456
llvm-svn: 283947
Inline virtual functions has linkeonceodr linkage (emitted in comdat on
supporting targets). If the vtable for the class is not emitted in the
defining module, function won't be address taken thus its address is not
recorded. At the mercy of the linker, if the per-func prf_data from this
module (in comdat) is picked at link time, we will lose mapping from
function address to its hash val. This leads to missing icall promotion.
The second test case (currently disabled) in compiler_rt (r271528):
instrprof-icall-prom.test demostrates the bug. The first profile-use
subtest is fine due to linker order difference.
With this change, no missing icall targets is found in instrumented clang's
raw profile.
llvm-svn: 271532
Summary:
The PS4 linker seems to handle this fine.
Hi David, it seems that indeed most ELF linkers support
__{start,stop}_SECNAME, as our proprietary linker does as well.
This follows the pattern of r250679 w.r.t. the testing.
Maggie, Phillip, Paul: I've tested this with the PS4 SDK 3.5 toolchain
prerelease and it seems to work fine.
Reviewers: davidxl
Subscribers: probinson, phillip.power, MaggieYi
Differential Revision: http://reviews.llvm.org/D17672
llvm-svn: 262112
This reduces sizes of instrumented object files, final binaries,
process images, and raw profile data.
The format of the indexed profile data remain the same.
Differential Revision: http://reviews.llvm.org/D16388
llvm-svn: 260117
The linker requires that a comdat section must be associated
with a another comdat section that precedes it. This
means the comdat section's name needs to use the profile name
var's name.
Patch tested by Johan Engelen.
llvm-svn: 256220
When targeting COFF, it is required that a comdat section to
have a global obj with the same name as the comdat (except for
comdats with select kind to be associative). This fix makes
sure that the comdat is keyed on the data variable for COFF.
Also improved test coverage for this.
llvm-svn: 256193
Profile symbols have long prefixes which waste space and creating pressure for linker.
This patch shortens the prefixes to minimal length without losing verbosity.
Differential Revision: http://reviews.llvm.org/D15503
llvm-svn: 255575
Before the patch, -fprofile-instr-generate compile will fail
if no integrated-as is specified when the file contains
any static functions (the -S output is also invalid).
This is the second try. The fix in this patch is very localized.
Only profile symbol names of profile symbols with internal
linkage are fixed up while initializer of name syms are not
changes. This means there is no format change nor version bump.
llvm-svn: 255434
This change introduces an instrumentation intrinsic instruction for
value profiling purposes, the lowering of the instrumentation intrinsic
and raw reader updates. The raw profile data files for llvm-profdata
testing are updated.
llvm-svn: 253484
Clang driver now injects -u<hook_var> flag in the linker
command line, in which case user function is not needed
any more.
Differential Revision: http://reviews.llvm.org/D14033
llvm-svn: 251612
On Linux, the profile runtime can use __start_SECTNAME and __stop_SECTNAME
symbols defined by the linker to locate the start and end location of
a named section (with C name). This eliminates the need for instrumented
binary to call __llvm_profile_register_function during start-up time.
llvm-svn: 250199
In -fprofile-instr-generate compilation, to remove the redundant profile
variables for the COMDAT functions, these variables are placed in the same
COMDAT group as its associated function. This way when the COMDAT function
is not picked by the linker, those profile variables will also not be
output in the final binary. This may cause warning when mix link objects
built w and wo -fprofile-instr-generate.
This patch puts the profile variables for COMDAT functions to its own COMDAT
group to avoid the problem.
Patch by xur.
Differential Revision: http://reviews.llvm.org/D12248
llvm-svn: 248440
This fixes a bit I forgot in r238335. In addition to the data record and
the counter, we can also move the name of the counter to the comdat for
the associated function.
I'm also adding an IR test case to check that these three elements are
placed in the proper comdat.
llvm-svn: 238351
Similar to gep (r230786) and load (r230794) changes.
Similar migration script can be used to update test cases, which
successfully migrated all of LLVM and Polly, but about 4 test cases
needed manually changes in Clang.
(this script will read the contents of stdin and massage it into stdout
- wrap it in the 'apply.sh' script shown in previous commits + xargs to
apply it over a large set of test cases)
import fileinput
import sys
import re
rep = re.compile(r"(getelementptr(?:\s+inbounds)?\s*\()((<\d*\s+x\s+)?([^@]*?)(|\s*addrspace\(\d+\))\s*\*(?(3)>)\s*)(?=$|%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|zeroinitializer|<|\[\[[a-zA-Z]|\{\{)", re.MULTILINE | re.DOTALL)
def conv(match):
line = match.group(1)
line += match.group(4)
line += ", "
line += match.group(2)
return line
line = sys.stdin.read()
off = 0
for match in re.finditer(rep, line):
sys.stdout.write(line[off:match.start()])
sys.stdout.write(conv(match))
off = match.end()
sys.stdout.write(line[off:])
llvm-svn: 232184
Essentially the same as the GEP change in r230786.
A similar migration script can be used to update test cases, though a few more
test case improvements/changes were required this time around: (r229269-r229278)
import fileinput
import sys
import re
pat = re.compile(r"((?:=|:|^)\s*load (?:atomic )?(?:volatile )?(.*?))(| addrspace\(\d+\) *)\*($| *(?:%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|\[\[[a-zA-Z]|\{\{).*$)")
for line in sys.stdin:
sys.stdout.write(re.sub(pat, r"\1, \2\3*\4", line))
Reviewers: rafael, dexonsmith, grosser
Differential Revision: http://reviews.llvm.org/D7649
llvm-svn: 230794
This symbol exists only to pull in the required pieces of the runtime,
so nothing ever needs to refer to it. Making it hidden avoids the
potential for issues with duplicate symbols when linking profiled
libraries together.
llvm-svn: 230566
This test checks that the symbols instrprof creates have appropriate
linkage. The tests already exist in clang in a slightly different form
from before we sunk profile generation into an LLVM pass, but that's
an awkward place for them now. I'll remove/simplify the clang versions
shortly.
llvm-svn: 230383
Introduce the ``llvm.instrprof_increment`` intrinsic and the
``-instrprof`` pass. These provide the infrastructure for writing
counters for profiling, as in clang's ``-fprofile-instr-generate``.
The implementation of the instrprof pass is ported directly out of the
CodeGenPGO classes in clang, and with the followup in clang that rips
that code out to use these new intrinsics this ends up being NFC.
Doing the instrumentation this way opens some doors in terms of
improving the counter performance. For example, this will make it
simple to experiment with alternate lowering strategies, and allows us
to try handling profiling specially in some optimizations if we want
to.
Finally, this drastically simplifies the frontend and puts all of the
lowering logic in one place.
llvm-svn: 223672
Reid Kleckner