llvm-project

Commit Graph

Author	SHA1	Message	Date
Georgii Rymar	98a4289810	[llvm-readobj] - For SHT_REL relocations, don't display an addend. This is https://bugs.llvm.org/show_bug.cgi?id=44257. In LLVM style we always print `0` as addend when dumping SHT_REL relocations. It is confusing, this patch stops printing it as the first comment on the bug page suggests. Differential revision: https://reviews.llvm.org/D93033	2020-12-14 12:03:00 +03:00
Fangrui Song	2bfee35cb8	[MC][ELF] Emit a relocation if target is defined in the same section and is non-local For a target symbol defined in the same section, currently we don't emit a relocation if VariantKind is VK_None (with few exceptions like RISC-V relaxation), while GNU as emits one. This causes program behavior differences with and without -ffunction-sections, and can break intended symbol interposition in a -shared link. ``` .globl foo foo: call foo # no relocation. On other targets, may be written as b foo, etc call bar # a relocation if bar is in another section (e.g. -ffunction-sections) call foo@plt # a relocation ``` Unify these cases by always emitting a relocation. If we ever want to optimize `call foo` in -shared links, we should emit a STB_LOCAL alias and call via the alias. ARM/thumb2-beq-fixup.s: we now emit a relocation to global_thumb_fn as GNU as does. X86/Inputs/align-branch-64-2.s: we now emit R_X86_64_PLT32 to foo as GNU does. ELF/relax.s: rewrite the test as target-in-same-section.s . We omitted relocations to `global` and now emit R_X86_64_PLT32. Note, GNU as does not emit a relocation for `jmp global` (maybe its own bug). Our new behavior is compatible except `jmp global`. Reviewed By: peter.smith Differential Revision: https://reviews.llvm.org/D72197	2020-01-12 13:46:24 -08:00
James Molloy	728cf85950	[Thumb1] Add relocations for fixups fixup_arm_thumb_{br,bcc} These need to be mapped through to R_ARM_THM_JUMP{11,8} respectively. Fixes PR30279. llvm-svn: 280651	2016-09-05 08:29:15 +00:00

Author

SHA1

Message

Date

Georgii Rymar

98a4289810

[llvm-readobj] - For SHT_REL relocations, don't display an addend.

This is https://bugs.llvm.org/show_bug.cgi?id=44257.

In LLVM style we always print `0` as addend when dumping
SHT_REL relocations. It is confusing, this patch stops
printing it as the first comment on the bug page suggests.

Differential revision: https://reviews.llvm.org/D93033

2020-12-14 12:03:00 +03:00

Fangrui Song

2bfee35cb8

[MC][ELF] Emit a relocation if target is defined in the same section and is non-local

For a target symbol defined in the same section, currently we don't emit
a relocation if VariantKind is VK_None (with few exceptions like RISC-V
relaxation), while GNU as emits one. This causes program behavior
differences with and without -ffunction-sections, and can break intended
symbol interposition in a -shared link.

```
.globl foo
foo:
  call foo      # no relocation. On other targets, may be written as b foo, etc
  call bar      # a relocation if bar is in another section (e.g. -ffunction-sections)
  call foo@plt  # a relocation
```

Unify these cases by always emitting a relocation. If we ever want to
optimize `call foo` in -shared links, we should emit a STB_LOCAL alias
and call via the alias.

ARM/thumb2-beq-fixup.s: we now emit a relocation to global_thumb_fn as GNU as does.
X86/Inputs/align-branch-64-2.s: we now emit R_X86_64_PLT32 to foo as GNU does.

ELF/relax.s: rewrite the test as target-in-same-section.s .
We omitted relocations to `global` and now emit R_X86_64_PLT32.
Note, GNU as does not emit a relocation for `jmp global` (maybe its own
bug). Our new behavior is compatible except `jmp global`.

Reviewed By: peter.smith

Differential Revision: https://reviews.llvm.org/D72197

2020-01-12 13:46:24 -08:00

James Molloy

728cf85950

[Thumb1] Add relocations for fixups fixup_arm_thumb_{br,bcc}

These need to be mapped through to R_ARM_THM_JUMP{11,8} respectively.

Fixes PR30279.

llvm-svn: 280651

2016-09-05 08:29:15 +00:00

3 Commits