Shengchen Kan 31dd29cfb3
[X86,lld] Handle relocation R_X86_64_REX2_GOTPCRELX (#109783)
For

	mov        name@GOTPCREL(%rip), %reg
	test       %reg, name@GOTPCREL(%rip)
	binop      name@GOTPCREL(%rip), %reg

where binop is one of adc, add, and, cmp, or, sbb, sub, xor
instructions, we added

 R_X86_64_REX2_GOTPCRELX = 43

in #106681.

Linker can treat R_X86_64_REX2_GOTPCRELX as R_X86_64_GOTPCREL or convert
the above instructions to

	lea	name(%rip), %reg
	mov	$name, %reg
	test	$name, %reg
	binop	$name, %reg

if the first byte of the instruction at the relocation `offset - 4` is
`0xd5` (namely, encoded w/ REX2 prefix) when possible.

Binutils patch:
3d5a60de52
Binutils mailthread:
https://sourceware.org/pipermail/binutils/2023-December/131462.html
ABI discussion: https://groups.google.com/g/x86-64-abi/c/KbzaNHRB6QU
Blog: https://kanrobert.github.io/rfc/All-about-APX-relocation
2024-09-29 12:52:36 +08:00
..
2024-08-30 10:50:56 -04:00
2023-05-02 09:34:48 +08:00
2023-08-21 09:11:51 -07:00
2024-01-22 09:09:46 -08:00
2024-07-28 12:38:10 -07:00
2023-07-18 17:57:31 -07:00
2024-06-14 23:20:50 -07:00
2023-07-25 17:06:07 +08:00
2023-07-25 17:06:07 +08:00
2024-09-16 13:12:45 -07:00
2023-07-18 17:57:31 -07:00
2024-04-19 09:09:41 -07:00
2024-05-15 15:41:20 -07:00
2024-07-15 10:39:23 +02:00
2024-07-31 12:57:23 -07:00