[Test][JITLink] Correctly generate the R_X86_64_PC8 relocation. #109283
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
maksfb
reviewed
Sep 20, 2024
| @@ -10,10 +10,4 @@ | |||
| main: | |||
| xorl %eax, %eax | |||
| retq | |||
| .size main, .-main | |||
|
|
|||
| .type P,@object | |||
There was a problem hiding this comment.
Thanks for spotting the issue and providing the fix. I'm not sure why loope would make llvm-mc emit relocation and .byte main-. would not. I suggest not to rely on the loope behavior and issue .byte main-. in a different section, e.g. .rodata. I.e. if you insert .rodata before .globl P, it will force llvm-mc to always emit a relocation.
There was a problem hiding this comment.
Thanks for the suggestion! I fixed it by emitting a byte main - . to the .rodata section.
Previously, ELF_R_X86_64_PC8.s doesn't produce the R_X86_64_PC8
relocation. This patch helps fix it by emitting a byte `main - .` to the
.rodata section.
Before:
```
llvm-mc -triple=x86_64-unknown-linux -position-independent -filetype=obj -o - ELF_R_X86_64_PC8.s | llvm-readobj -r -
File: <stdin>
Format: elf64-x86-64
Arch: x86_64
AddressSize: 64bit
LoadName: <Not found>
Relocations [
]
```
After:
```
llvm-mc -triple=x86_64-unknown-linux -position-independent -filetype=obj -o - ELF_R_X86_64_PC8.s | llvm-readobj -r -
File: <stdin>
Format: elf64-x86-64
Arch: x86_64
AddressSize: 64bit
LoadName: <Not found>
Relocations [
Section (4) .rela.rodata {
0x0 R_X86_64_PC8 main 0x0
}
]
```
higuoxing
force-pushed
the
jitlink-test-reloc
branch
from
bc5b9b4 to
953dbfa
Compare
lhames
approved these changes
Sep 22, 2024
higuoxing
changed the title
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Previously, ELF_R_X86_64_PC8.s doesn't produce the R_X86_64_PC8 relocation. This patch helps fix it.
Before:
After: