[SPIR-V] Fix OpBitFieldExtract emulation for unsigned integer #7167
+12
−8
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
For an unsigned integer, we should OpShiftRightLogical instead of
OpShiftRightArithmetic. Otherwise the value may be extended incorrectly.
For example:
```
struct S {
uint16_t m1 : 8;
uint16_t m2 : 8;
};
void main() {
S s;
s.m1 = 0xff;
s.m2 = 0xff;
uint16_t result = s.m1;
}
```
If we do OpShiftRightArithmetic here, the result will be 0xffff.
s-perron
approved these changes
Feb 28, 2025
# for free
to join this conversation on GitHub.
Already have an account?
# 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Outdated suggestions cannot be applied.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.
For an unsigned integer, we should OpShiftRightLogical instead of OpShiftRightArithmetic. Otherwise the value may be extended incorrectly.
For example:
If we do OpShiftRightArithmetic here, the result will be 0xffff.