Skip stack accesses unless requested, as the memory profiler runtime
does not currently look at or report accesses for these addresses.
Differential Revision: https://reviews.llvm.org/D109868
This removes an abuse of ELF linker behaviors while keeping Mach-O/COFF linker
behaviors unchanged.
ELF: when module_ctor is in a comdat, this patch removes reliance on a linker
abuse (an SHT_INIT_ARRAY in a section group retains the whole group) by using
SHF_GNU_RETAIN. No linker behavior difference when module_ctor is not in a comdat.
Mach-O: module_ctor gets `N_NO_DEAD_STRIP`. No linker behavior difference
because module_ctor is already referenced by a `S_MOD_INIT_FUNC_POINTERS`
section (GC root).
PE/COFF: no-op. SanitizerCoverage already appends module_ctor to `llvm.used`.
Other sanitizers: llvm.used for local linkage is not implemented in
`TargetLoweringObjectFileCOFF::emitLinkerDirectives` (once implemented or
switched to a non-local linkage, COFF can use module_ctor in comdat (i.e.
generalize ELF-specific rL301586)).
There is no object file size difference.
Reviewed By: vitalybuka
Differential Revision: https://reviews.llvm.org/D106246
The x86-64 backend currently has a bug which uses a wrong register when for the GOTPCREL reference.
The program will crash without the dso_local specifier.
Similar to -fprofile-generate=, add -fmemory-profile= which takes a
directory path. This is passed down to LLVM via a new module flag
metadata. LLVM in turn provides this name to the runtime via the new
__memprof_profile_filename variable.
Additionally, always pass a default filename (in $cwd if a directory
name is not specified vi the = form of the option). This is also
consistent with the behavior of the PGO instrumentation. Since the
memory profiles will generally be fairly large, it doesn't make sense to
dump them to stderr. Also, importantly, the memory profiles will
eventually be dumped in a compact binary format, which is another reason
why it does not make sense to send these to stderr by default.
Change the existing memprof tests to specify log_path=stderr when that
was being relied on.
Depends on D89086.
Differential Revision: https://reviews.llvm.org/D89087
This is consistent with the clang option added in
7ed8124d46, and the comments on the
runtime patch in D87120.
Differential Revision: https://reviews.llvm.org/D87622
See RFC for background:
http://lists.llvm.org/pipermail/llvm-dev/2020-June/142744.html
Note that the runtime changes will be sent separately (hopefully this
week, need to add some tests).
This patch includes the LLVM pass to instrument memory accesses with
either inline sequences to increment the access count in the shadow
location, or alternatively to call into the runtime. It also changes
calls to memset/memcpy/memmove to the equivalent runtime version.
The pass is modeled on the address sanitizer pass.
The clang changes add the driver option to invoke the new pass, and to
link with the upcoming heap profiling runtime libraries.
Currently there is no attempt to optimize the instrumentation, e.g. to
aggregate updates to the same memory allocation. That will be
implemented as follow on work.
Differential Revision: https://reviews.llvm.org/D85948
Teresa Johnson