RFR: 8144028: Use AArch64 bit-test instructions in C2

Edward Nevill edward.nevill at gmail.com
Wed Nov 25 16:56:08 UTC 2015

On Wed, 2015-11-25 at 15:49 +0000, Andrew Haley wrote:
> For some reason (oversight, I guess) we never got around to using the
> bit-testing AArch64 instructions in C2.  TBZ/TBNZ are quite nice in
> that they allow bit tests and branches (and tests for +ve/-ve) without
> hitting the condition codes.  TST sets the condition codes based on a
> set of bits in a register: it's an AND which throws the result away.
> http://cr.openjdk.java.net/~aph/8144028/

Looks fine. Small typo.

In cmpL_branch_sign and cmpI_branch_sign

+  format %{ "cb$cmp   $op1, $labl" %}

should be "tb$cmp ..."


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