[PATCH] D62862: [ELF][LLD] Allow reading of more than one FEATURE_1_AND in same object.

[Peter Smith via Phabricator via llvm-commits]

peter.smith created this revision.
peter.smith added reviewers: ruiu, MaskRay.
Herald added subscribers: kristof.beyls, arichardson, javed.absar, emaste.
Herald added a reviewer: espindola.
peter.smith added a parent revision: D62853: Read .note.gnu.property sections and emit a merged .note.gnu.property section..

This patch is a follow on from D62853 <https://reviews.llvm.org/D62853> . Although many relocatable objects will have a single GNU_PROPERTY_X86_FEATURE_1_AND in the .note.gnu.property section it is permissible to have more than one, and there is a test in ld.bfd that uses it. The behavior that ld.bfd follows is to set the feature bit for a relocatable object if any of the GNU_PROPERTY_X86_FEATURE_1_AND have the feature bit set.

The specific test in ld.bfd is https://github.com/bminor/binutils-gdb/blob/master/ld/testsuite/ld-aarch64/property-bti-pac1.s there isn't an X86 equivalent test but the same behaviour can be observed with IBT and SHSTK. I've added a test case for that.

This could be considered a corner case, however it is not known whether tools will just add another GNU_PROPERTY_X86_FEATURE_1_AND rather than find an existing one and add to it.


https://reviews.llvm.org/D62862

Files:
  ELF/InputFiles.cpp
  test/ELF/i386-cet.s
  test/ELF/x86-property-relocatable.s

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