With old "medium" code model, we call a function with a pair of PCALAU12I
and JIRL instructions. The assembler produces something like:
8: 1a00000c pcalau12i $t0, 0
8: R_LARCH_PCALA_HI20 g
c: 4c000181 jirl $ra, $t0, 0
c: R_LARCH_PCALA_LO12 g
The linker generates a "PLT entry" for data without any diagnostic.
If "g" is a data symbol and ld with -shared option, it may load two
instructions in the PLT.
Without -shared option, loongarch_elf_adjust_dynamic_symbol can delete PLT
entry.
For R_LARCH_PCALA_HI20 relocation, linker only generate PLT entry for STT_FUNC
and STT_GNU_IFUNC symbols.
If the symbol index is not zero, the addend is used to represent
the first and the third expressions of the .align.
The lowest 8 bits are used to represent the first expression.
Other bits are used to represent the third expression.
The addend of R_LARCH_ALIGN for ".align 5, ,4" is 0x405.
The addend of R_LARCH_ALIGN for ".balign 32, ,4" is 0x405.
R_LARCH_CALL36 is used for medium code model function call pcaddu18i+jirl, and
these two instructions must adjacent.
The LoongArch ABI v2.20 at here: https://github.com/loongson/la-abi-specs.
The newer update-copyright.py fixes file encoding too, removing cr/lf
on binutils/bfdtest2.c and ld/testsuite/ld-cygwin/exe-export.exp, and
embedded cr in binutils/testsuite/binutils-all/ar.exp string match.
loongarch_elf_finish_dynamic_symbol is called after elf_link_sort_relocs
if -z combreloc. elf_link_sort_relocs redistributes the contents of
.rela.* sections those would be merged into .rela.dyn, so the slot for
R_LARCH_IRELATIVE may be out of relplt->contents now.
To make things worse, the boundary check
dyn < dyn + relplt->size / sizeof (*dyn)
is obviously wrong ("x + 10 < x"? :), causing the issue undetected
during the linking process and the resulted executable suddenly crashes
at runtime.
The issue was found during an attempt to add static-pie support to the
toolchain.
Fix it by iterating through the inputs of .rela.dyn to find the slot.
ld/testsuite/ld-loongarch-elf
* ld-loongarch-elf.exp: Test LoongArch32 and LoongArch64 testcases respectively.
* jmp_op.d: Fix bug in test LoongArch32.
* disas-jirl-32.d: New test case for LoongArch32.
* disas-jirl-32.s: New test case for LoongArch32.
* disas-jirl.d: Skip test case LoongArch32.
* macro_op_32.d: New test case for LoongArch32.
* macro_op_32.s: New test case for LoongArch32.
* macro_op.d: Skip test case LoongArch32.
The result of running etc/update-copyright.py --this-year, fixing all
the files whose mode is changed by the script, plus a build with
--enable-maintainer-mode --enable-cgen-maint=yes, then checking
out */po/*.pot which we don't update frequently.
The copy of cgen was with commit d1dd5fcc38ead reverted as that commit
breaks building of bfp opcodes files.
