ReleaseNotes: add lld/ELF notes

Pull Request: #124508

Author: MaskRay

lld/docs/ReleaseNotes.rst

@@ -29,12 +29,45 @@ ELF Improvements
 * ``-z nosectionheader`` has been implemented to omit the section header table.
   The operation is similar to ``llvm-objcopy --strip-sections``.
   (`#101286 <https://github.com/llvm/llvm-project/pull/101286>`_)
+* ``--randomize-section-padding=<seed>`` is introduced to insert random padding
+  between input sections and at the start of each segment. This can be used to
+  control measurement bias in A/B experiments.
+  (`#117653 <https://github.com/llvm/llvm-project/pull/117653>`_)
+* The reproduce tarball created with ``--reproduce=`` now excludes directories
+  specified in the ``--dependency-file`` argument (used by Ninja). This
+  resolves an error where non-existent directories could cause issues when
+  invoking ``ld.lld @response.txt``.
+* ``--symbol-ordering-file=`` and call graph profile can now be used together.
+* When ``--call-graph-ordering-file=`` is specified, ``.llvm.call-graph-profile``
+  sections in relocatable files are no longer used.
+* ``--lto-basic-block-sections=labels`` is deprecated in favor of
+  ``--lto-basic-block-address-map``.
+  (`#110697 <https://github.com/llvm/llvm-project/pull/110697>`_)
+* In non-relocatable links, a ``.note.GNU-stack`` section with the
+  ``SHF_EXECINSTR`` flag is now rejected unless ``-z execstack`` is specified.
+  (`#124068 <https://github.com/llvm/llvm-project/pull/124068>`_)
+* In relocatable links, the ``sh_entsize`` member of a ``SHF_MERGE`` section
+  with relocations is now respected in the output.
+* Quoted names can now be used in output section phdr, memory region names,
+  ``OVERLAY``, the LHS of ``--defsym``, and ``INSERT AFTER``.
 * Section ``CLASS`` linker script syntax binds input sections to named classes,
   which are referenced later one or more times. This provides access to the
   automatic spilling mechanism of `--enable-non-contiguous-regions` without
   globally changing the semantics of section matching. It also independently
   increases the expressive power of linker scripts.
   (`#95323 <https://github.com/llvm/llvm-project/pull/95323>`_)
+* ``INCLUDE`` cycle detection has been fixed. A linker script can now be
+  included twice.
+* The ``archivename:`` syntax when matching input sections is now supported.
+  (`#119293 <https://github.com/llvm/llvm-project/pull/119293>`_)
+* To support Arm v6-M, short thunks using B.w are no longer generated.
+  (`#118111 <https://github.com/llvm/llvm-project/pull/118111>`_)
+* For AArch64, BTI-aware long branch thunks can now be created to a destination
+  function without a BTI instruction.
+  (`#108989 <https://github.com/llvm/llvm-project/pull/108989>`_)
+  (`#116402 <https://github.com/llvm/llvm-project/pull/116402>`_)
+* Relocations related to GOT and TLSDESC for the AArch64 Pointer Authentication ABI
+  are now supported.
 * Supported relocation types for x86-64 target:
   * ``R_X86_64_CODE_4_GOTPCRELX`` (`#109783 <https://github.com/llvm/llvm-project/pull/109783>`_) (`#116737 <https://github.com/llvm/llvm-project/pull/116737>`_)
   * ``R_X86_64_CODE_4_GOTTPOFF`` (`#116634 <https://github.com/llvm/llvm-project/pull/116634>`_)