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Re: [PATCH] rs6000: Fix the shift patterns, and add test

On Wed, Jul 2, 2014 at 5:06 PM, Segher Boessenkool
<> wrote:
> Firstly, it adds back the split conditions that I accidentally removed.
> Without it the dot insns are never generated, or rather, always split
> back to a separate compare instruction.
> Secondly, the shift amount should be SI always, not GPR, or GCC will
> insert a zero-extend at expand time that it cannot get rid of later.


> The test tests whether dot-form instructions are generated for both
> "dot" and "dot2" cases, that is, with just a CC output or also a GPR
> output; for all four basic shifts, with a register amount or an
> immediate amount.  It also tests for superfluous zero-extends.  This
> also tests if combine "simplifies" the rotates to right-rotates, which
> it shouldn't do anymore.
> Bootstrapped and tested as usual.  Okay to commit?
> Segher
> 2014-07-02  Segher Boessenkool  <>
> gcc/
>         * config/rs6000/ (rotl<mode>3, ashl<mode>3, lshr<mode>3,
>         ashr<mode>3): Correct mode of operands[2].
>         (rotl<mode>3_dot, rotl<mode>3_dot2, ashl<mode>3_dot, ashl<mode>3_dot2,
>         lshr<mode>3_dot, lshr<mode>3_dot2, ashr<mode>3_dot, ashr<mode>3_dot2):
>         Correct mode of operands[2].  Fix split condition.
> gcc/testsuite/
>         * New test.


Thanks, David

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