…ions.

`DTLS_on_libc_memalign` is called from primary
allocator, so `__sanitizer_get_allocated_begin`
should also be aware of allocation,
and correctly handled by `GetDTLSRange`.

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

It was added for RTEMS which was removed at D104279.

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