Since glibc 2.34, dlsym does
1. malloc 1
2. malloc 2
3. free pointer from malloc 1
4. free pointer from malloc 2
These sequence was not handled by trivial dlsym hack.
This fixes https://bugs.llvm.org/show_bug.cgi?id=52278
Reviewed By: eugenis, morehouse
Differential Revision: https://reviews.llvm.org/D112588
See RFC for background:
http://lists.llvm.org/pipermail/llvm-dev/2020-June/142744.html
Follow on companion to the clang/llvm instrumentation support in D85948
and committed earlier.
This patch adds the compiler-rt runtime support for the memory
profiling.
Note that much of this support was cloned from asan (and then greatly
simplified and renamed). For example the interactions with the
sanitizer_common allocators, error handling, interception, etc.
The bulk of the memory profiling specific code can be found in the
MemInfoBlock, MemInfoBlockCache, and related classes defined and used
in memprof_allocator.cpp.
For now, the memory profile is dumped to text (stderr by default, but
honors the sanitizer_common log_path flag). It is dumped in either a
default verbose format, or an optional terse format.
This patch also adds a set of tests for the core functionality.
Differential Revision: https://reviews.llvm.org/D87120