[PATCH 2/2] s390: Do not rewrite insns and their relocs in linker if --no-relax

[Andreas Krebbel]

On 10/15/25 6:17 PM, Jens Remus wrote:
> Under certain conditions the linker rewrites:
> - GOT access using lgrl to larl, changing the GOTENT to a PC32DBL reloc
> - GOT access using lg to larl, changing the GOT20 to a PC32DBL reloc
> - Relative long addressing instructions of weak symbols, which
>    definitively resolve to zero to either (1) load address of zero,
>    (2) a NOP, or (3) a trapping instruction, changing the relocation to
>    a NONE reloc.
>
> Suppress rewriting of non-TLS instructions and related relocations in
> linker if option --no-relax is specified.  This aligns with LLVM linker
> behavior on s390.
>
> Like x86-64 do not actually enable the linker relaxation option by
> default, as other targets would do using ENABLE_RELAXATION or
> TARGET_ENABLE_RELAXATION in their linker emulation scripts.  Instead
> perform linker instruction/relocation rewrites by default unless linker
> option --no-relax is explicitly specified by the user.  This ensures no
> functional change unless --no-relax is used.
>
> bfd/
> 	* elf64-s390.c (elf_s390_relocate_section): Do not rewrite
> 	non-TLS instructions and related relocations if --no-relax.
> 	* elf32-s390.c (elf_s390_relocate_section): Likewise.
>
> ld/testsuite/
> 	* ld-s390/s390.exp: New tests.  Same as gotreloc_*-1a and
> 	weakundef-*a, but with linker option --no-relax, to verify
> 	suppression of linker non-TLS insn and reloc rewrites.
> 	* ld-s390/gotreloc_31-1b.dd: Likewise.
> 	* ld-s390/gotreloc_31-no-pie-1b.dd: Likewise.
> 	* ld-s390/gotreloc_64-no-pie-1b.dd: Likewise.
> 	* ld-s390/gotreloc_64-norelro-1b.dd: Likewise.
> 	* ld-s390/gotreloc_64-relro-1b.dd: Likewise.
> 	* ld-s390/weakundef-1b.d: Likewise.  Check for expected reloc
> 	overflows.
> 	* ld-s390/weakundef-2b.d: Likewise.
>
> Signed-off-by: Jens Remus <jremus@linux.ibm.com>

Ok, thanks!

Andreas