cmd/internal/obj/arm64: fix incorrect rejection of legal instructions

"BFI $0, R1, $7, R2" is expected to copy bit 0~6 from R1 to R2, and
left R2's other bits unchanged.

But the assembler rejects it with error "illegal bit number", and
BFIW/SBFIZ/SBFIZW/UBFIZ/UBFIZW have the same problem.

This CL fixes that issue and adds corresponding test cases.

fixes #26736

Change-Id: Ie0090a0faa38a49dd9b096a0f435987849800b76
Run-TryBot: Ben Shi <>
Reviewed-by: Cherry Zhang <>
2 files changed
tree: 4c66ab580fa1254b5d172b4424046f09a519b68a
  1. .gitattributes
  2. .github/
  3. .gitignore
  10. api/
  11. doc/
  12. favicon.ico
  13. lib/
  14. misc/
  15. robots.txt
  16. src/
  17. test/

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