RFR: 8354815: RISC-V: Change type of bitwise rotation shift to iRegIorL2I

Feilong Jiang fjiang at openjdk.org
Thu Apr 17 12:34:53 UTC 2025


On Mon, 14 Apr 2025 09:46:34 GMT, Anjian-Wen <duke at openjdk.org> wrote:

> There is no need to do a type conversion when the shift amount of bitwise rotation is an integer converted from long (ConvL2I).
> There reason is that these instruction performs a rotate right/left of source by the amount in the least-significant 5/6 bits
> of the shift amount depending on the width of the operation (32-bit/64-bit). For 32-bit operations, the resulting 32-bit
> value is sign-extended by copying bit 31 to all of the more-significant bits. This means that we could use iRegIorL2I type for
> source for these 32-bit operations as well.
> 
> Jtreg Testing in progress

Looks good!

-------------

Marked as reviewed by fjiang (Committer).

PR Review: https://git.openjdk.org/jdk/pull/24618#pullrequestreview-2775572348


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