Summary:
Currently, RuntimeDyld will not allocate a section without relocations
even if such a section is marked allocatable and defines symbols.
When we emit .debug_line for compile units with unchanged code, we
output original (input) data, without relocations. If all units are
emitted in this way, we will have no relocations in the emitted
.debug_line. RuntimeDyld will not allocate the section and as a result
we will write an empty .debug_line section.
To workaround the issue, always emit a relocation of RELOC_NONE type
when emitting raw contents to debug_line.
(cherry picked from FBD32909869)
Summary:
With LTO, it's possible for multiple DWARF compile units to share the
same abbreviation section set, i.e. to have the same abbrev_offset.
When units sharing the same abbrev set are located next to each other
and neither of them is being processed (i.e. contain processed
functions), it can trigger a bug in BOLT. When this happened,
the abbrev set is considered empty. Additionally, different units
may patch abbrev section differently.
The fix is to not rely on the next unit offset when detecting
abbreviation set boundaries and to delay writing abbrev section
until all units are processed.
(cherry picked from FBD31985046)
Summary:
Moves source files into separate components, and make explicit
component dependency on each other, so LLVM build system knows how to
build BOLT in BUILD_SHARED_LIBS=ON.
Please use the -c merge.renamelimit=230 git option when rebasing your
work on top of this change.
To achieve this, we create a new library to hold core IR files (most
classes beginning with Binary in their names), a new library to hold
Utils, some command line options shared across both RewriteInstance
and core IR files, a new library called Rewrite to hold most classes
concerned with running top-level functions coordinating the binary
rewriting process, and a new library called Profile to hold classes
dealing with profile reading and writing.
To remove the dependency from BinaryContext into X86-specific classes,
we do some refactoring on the BinaryContext constructor to receive a
reference to the specific backend directly from RewriteInstance. Then,
the dependency on X86 or AArch64-specific classes is transfered to the
Rewrite library. We can't have the Core library depend on targets
because targets depend on Core (which would create a cycle).
Files implementing the entry point of a tool are transferred to the
tools/ folder. All header files are transferred to the include/
folder. The src/ folder was renamed to lib/.
(cherry picked from FBD32746834)
