From: Fangrui Song <maskray@google.com>
To: liuzhensong <liuzhensong@loongson.cn>
Cc: binutils@sourceware.org, i.swmail@xen0n.name, xry111@xry111.site
Subject: Re: [PATCH v2] LoongArch:ld: Fix relocation error of pcrel.
Date: Sat, 3 Sep 2022 09:55:49 -0700 [thread overview]
Message-ID: <CAFP8O3KVzE04u4ooT26f=+1DhprdGDfhj3bNztXFZ1dA4MPYbQ@mail.gmail.com> (raw)
In-Reply-To: <20220903084149.1612310-1-liuzhensong@loongson.cn>
On Sat, Sep 3, 2022 at 1:43 AM liuzhensong <liuzhensong@loongson.cn> wrote:
>
> Patch for branch 2.39.
> Need to reduce the address of pc when using
> reloction R_LARCH_SOP_PUSH_PCREL.
>
> bfd/
> * elfnn-loongarch.c
> ---
> bfd/elfnn-loongarch.c | 3 +-
> ld/testsuite/ld-loongarch-elf/pcrel-const.d | 14 +++++++
> ld/testsuite/ld-loongarch-elf/pcrel-const.lds | 14 +++++++
> ld/testsuite/ld-loongarch-elf/pcrel-const.s | 12 ++++++
> ld/testsuite/ld-loongarch-elf/pr.exp | 39 +++++++++++++++++++
> 5 files changed, 81 insertions(+), 1 deletion(-)
> create mode 100644 ld/testsuite/ld-loongarch-elf/pcrel-const.d
> create mode 100644 ld/testsuite/ld-loongarch-elf/pcrel-const.lds
> create mode 100644 ld/testsuite/ld-loongarch-elf/pcrel-const.s
> create mode 100644 ld/testsuite/ld-loongarch-elf/pr.exp
>
> diff --git a/bfd/elfnn-loongarch.c b/bfd/elfnn-loongarch.c
> index 5b44901b9e0..fafdc7c7458 100644
> --- a/bfd/elfnn-loongarch.c
> +++ b/bfd/elfnn-loongarch.c
> @@ -2341,9 +2341,10 @@ loongarch_elf_relocate_section (bfd *output_bfd, struct bfd_link_info *info,
> case R_LARCH_SOP_PUSH_PLT_PCREL:
> unresolved_reloc = false;
>
> - if (resolved_to_const)
> + if (!is_undefweak && resolved_to_const)
> {
> relocation += rel->r_addend;
> + relocation -= pc;
> break;
> }
> else if (is_undefweak)
> diff --git a/ld/testsuite/ld-loongarch-elf/pcrel-const.d b/ld/testsuite/ld-loongarch-elf/pcrel-const.d
> new file mode 100644
> index 00000000000..ae4705aa531
> --- /dev/null
> +++ b/ld/testsuite/ld-loongarch-elf/pcrel-const.d
> @@ -0,0 +1,14 @@
> +#as: -mla-global-with-pcrel
> +#objdump: -Drsz
> +
> +.*:[ ]+file format .*
> +
> +
> +Disassembly of section .text:
> +
> +.* <foo>:
> +#...
> +[ ]+8:[ ]+02c04084[ ]+addi.d[ ]+\$a0,[ ]+\$a0,[ ]+16\(0x10\)
> +#...
> +0+14 <__sec_end>:
> +#pass
> diff --git a/ld/testsuite/ld-loongarch-elf/pcrel-const.lds b/ld/testsuite/ld-loongarch-elf/pcrel-const.lds
> new file mode 100644
> index 00000000000..34b9861f4fa
> --- /dev/null
> +++ b/ld/testsuite/ld-loongarch-elf/pcrel-const.lds
> @@ -0,0 +1,14 @@
> +ENTRY(foo);
> +SECTIONS
> +{
> + .text : {
> + *(.text*)
> + }
> +
> + .data : {
> + __sec_start = .;
> + *(.gzdata)
> + __sec_end = .;
> + }
> +}
> +PROVIDE(__sec_size = __sec_end);
__sec_size is now the address of __sec_end instead of a size. Is this
intentional?
> diff --git a/ld/testsuite/ld-loongarch-elf/pcrel-const.s b/ld/testsuite/ld-loongarch-elf/pcrel-const.s
> new file mode 100644
> index 00000000000..8b4a9d7aea0
> --- /dev/null
> +++ b/ld/testsuite/ld-loongarch-elf/pcrel-const.s
> @@ -0,0 +1,12 @@
> + .text
> + .align 2
> + .globl foo
> + .type foo, @function
> +foo:
> + nop
> + la.global $r4,__sec_size
> + ldptr.w $r4,$r4,0
> + jr $r1
> + .size foo, .-foo
> + .data
> + .word 1
> diff --git a/ld/testsuite/ld-loongarch-elf/pr.exp b/ld/testsuite/ld-loongarch-elf/pr.exp
> new file mode 100644
> index 00000000000..c0cc2fc30d2
> --- /dev/null
> +++ b/ld/testsuite/ld-loongarch-elf/pr.exp
> @@ -0,0 +1,39 @@
> +# Expect script for LoongArch ELF linker tests
> +# Copyright (C) 2022 Free Software Foundation, Inc.
> +#
> +# This file is part of the GNU Binutils.
> +#
> +# This program is free software; you can redistribute it and/or modify
> +# it under the terms of the GNU General Public License as published by
> +# the Free Software Foundation; either version 3 of the License, or
> +# (at your option) any later version.
> +#
> +# This program is distributed in the hope that it will be useful,
> +# but WITHOUT ANY WARRANTY; without even the implied warranty of
> +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> +# GNU General Public License for more details.
> +#
> +# You should have received a copy of the GNU General Public License
> +# along with this program; if not, write to the Free Software
> +# Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
> +# MA 02110-1301, USA.
> +#
> +
> +if ![istarget loongarch64-*-*] {
> + return
> +}
> +
> +set link_tests [list \
> + [list \
> + "pcrel const" \
> + "-T pcrel-const.lds" "" \
> + "-mla-global-with-pcrel" \
> + { pcrel-const.s } \
> + [list \
> + [list objdump -D pcrel-const.d] \
> + ] \
> + "pcrel-const" \
> + ] \
> +]
> +
> +run_ld_link_tests $link_tests
> --
> 2.31.1
>
--
宋方睿
next prev parent reply other threads:[~2022-09-03 16:56 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-09-03 8:41 liuzhensong
2022-09-03 16:55 ` Fangrui Song [this message]
2022-09-05 1:17 ` liuzhensong
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