Add logging to report any failures that may occur on calls to libdl. Without
this, it is difficult to identify the actual problem if the test fails.
llvm-svn: 209097
Shared objects are hard. After this commit, we do the right thing when
profiling two separate shared objects that have been dlopen'd with
`RTLD_LOCAL`, when the main executable is *not* being profiled.
This mainly simplifies the writer logic.
- At initialization, determine the output filename and truncate the
file. Depending on whether shared objects can see each other, this
may happen multiple times.
- At exit, each executable writes its own profile in append mode.
<rdar://problem/16918688>
llvm-svn: 209053
Change the API of the instrumented profiling library to work with shared
objects.
- Most things are now declared hidden, so that each executable gets
its own copy.
- Initialization hooks up a linked list of writers.
- The raw format with shared objects that are profiled consists of a
concatenated series of profiles. llvm-profdata knows how to deal
with that since r208938.
<rdar://problem/16918688>
llvm-svn: 208940
Saleem Abdulrasool