[arm] account for signed bit when calculating offset to PLT entry #18454
Conversation
This file contains 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
vargaz
reviewed
Jan 15, 2020
mono/mini/tramp-arm.c
Outdated
| @@ -1128,7 +1128,7 @@ mono_arm_get_thumb_plt_entry (guint8 *code) | |||
|
|
|||
| g_assert ((t1 >> 11) == 0x1e); | |||
|
|
|||
| s = (t1 >> 10) & 0x1; | |||
| s = (t1 >> 10) & 0x1 ? 1 : 0; | |||
| imm10 = (t1 >> 0) & 0x3ff; | |||
vargaz
approved these changes
Jan 15, 2020
jaykrell
reviewed
Jan 15, 2020
| /* Sign extend from 24 bits to 32 bits */ | ||
| imm32 = ((gint32)imm32 << 8) >> 8; | ||
| /* Sign extend from 25 bits to 32 bits */ | ||
| imm32 = ((gint32)imm32 << 7) >> 7; |
There was a problem hiding this comment.
Maybe worth a helper function. Like:
https://github.com/microsoft/Detours/blob/64ec135a509884aa60ac6c19b59564f1da9cb2fa/src/detours.cpp#L1019
or
https://github.com/microsoft/Detours/blob/64ec135a509884aa60ac6c19b59564f1da9cb2fa/src/disasm.cpp#L1867
(MIT licensed)
|
@monojenkins squash |
|
@monojenkins backport 2019-12 |
|
@monojenkins backport 2019-10 |
This was referenced Jan 15, 2020
monojenkins
added a commit
that referenced
this pull request
Jan 16, 2020
… entry (#18461) [2019-10] [arm] account for signed bit when calculating offset to PLT entry See `bl` documentation (make sure you look at the thumb2 one): <img width="1003" alt="Screenshot 2020-01-14 at 22 43 33" src="https://user-images.githubusercontent.com/75403/72385601-2bb53b00-3720-11ea-9858-d73bc2d02a7e.png"> Fixes #18247 Backport of #18454. /cc @lewurm
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Outdated suggestions cannot be applied.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.
See
bldocumentation (make sure you look at the thumb2 one):Fixes #18247