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
This patch creates the profile data variable before lowering the profile intrinsics.
Reviewers: davidxl, silvas
Differential Revision: http://reviews.llvm.org/D16015
llvm-svn: 258156
Coverage mapping data may reference names of functions
that are skipped by FE (e.g, unused inline functions). Since
those functions are skipped, normal instr-prof function lowering
pass won't put those names in the right section, so special
handling is needed to walk through coverage mapping structure
and recollect the references.
With this patch, only names that are skipped are processed. This
simplifies the lowering code and it no longer needs to make
assumptions coverage mapping data layout. It should also be
more efficient.
llvm-svn: 257091
This is one last remaining instrumentatation related structure
that needs to be migrate to use the centralized template
definition. With this change, instrumentation code
related to coverage module header will be kept in sync
with the coverage mapping reader. The remaining code
which makes implicit assumption about covmap control
structure layout in the the lowering pass will cleaned
up in a different patch. This patch is not intended to
have no functional change.
llvm-svn: 256715
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
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
In profile runtime implementation for Darwin, Linux and FreeBSD, the
names of sections holding profile control/counter/naming data need
to be known by the runtime in order to locate the start/end of the
data. Moving the name definitions to the common file to specify the
connection.
llvm-svn: 253814
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
With this change, instrumentation code and reader/write
code related to profile data structs are kept strictly
in-sync. THis will be extended to cfe and compile-rt
references as well.
Differential Revision: http://reviews.llvm.org/D13843
llvm-svn: 252113
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
This patch converts the remaining references to literal
strings for names of profile runtime entites (such as
profile runtime hook, runtime hook use function, profile
init method, register function etc).
Also added documentation for all the new interfaces.
llvm-svn: 251093
This is a clean up patch that defines instr prof section and variable
name prefixes in a common header with access helper functions.
clang FE change will be done as a follow up once this patch is in.
Differential Revision: http://reviews.llvm.org/D13919
llvm-svn: 251058
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
Counter symbols created for linkonce functions are not discarded by ELF
linkers unless the symbols are placed in the same comdat section as its
associated function.
llvm-svn: 238335
This change is the second of 3 patches to add support for specifying
the profile output from the command line via -fprofile-instr-generate=<path>,
where the specified output path/file will be overridden by the
LLVM_PROFILE_FILE environment variable.
This patch adds the necessary support to the llvm instrumenter, specifically
a new member of GCOVOptions for clang to save the specified filename, and
support for calling the new compiler-rt interface from __llvm_profile_init.
Patch by Teresa Johnson. Thanks!
llvm-svn: 236288
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
Add handling for __llvm_coverage_mapping to the InstrProfiling
pass. We need to make sure the constant and any profile names it
refers to are in the correct sections, which is easier and cleaner to
do here where we have to know about profiling sections anyway.
This is really tricky to test without a frontend, so I'm committing
the test for the fix in clang. If anyone knows a good way to test this
within LLVM, please let me know.
Fixes PR22531.
llvm-svn: 228793
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
