Landing: 5d98400b5a77

Project / Subsystem

gcc / gcc/vector

Date

2026-07-15

Author

Pan Li

Commit

5d98400b5a77795c5103dbfe3f4a19f51c04f4c6

Source

github

Perf win

Yes

Breaking

No

All attributes

project
gcc
subsystem
gcc/vector
patch_id
commit_hash
5d98400b5a77795c5103dbfe3f4a19f51c04f4c6
source_type
github
headline
RISC-V: Align vwcvt[u].x.x.v with vsext.vf8 register overlap rules
tldr
RISC-V vector extension allows register overlap for vwcvt[u].x.x.v instructions, similar to vsext.vf8.
author
Pan Li
outcome
committed
performance_win
true
breaking_change
false
series_id
series_parts
[]
tags
  • risc-v
  • vector extension
  • optimization
discussion_id_link
bugzilla_pr
date
2026-07-15T00:00:00.000Z

This change allows the RISC-V vector extension’s vwcvt[u].x.x.v instructions to utilize register overlap. By leveraging the Wvr constraint in the vector instruction definition, the compiler can now generate code where the destination vector register set overlaps with the source register set, similar to the existing behavior of v[sz]ext.vf8.