Re: [x86 PATCH] Convert ptestz of pandn into ptestc.

On Fri, Jun 16, 2023 at 3:27 PM Roger Sayle wrote: > > > Hi Uros, > Here's an updated version of this patch incorporating your comments. > It uses emit_insn (target, const1_rtx), bt_comparison operator to > combine the sete/setne to setc/setnc, and je/jne to jc/jnc patterns, > uses scan-assembler-

RE: [x86 PATCH] Convert ptestz of pandn into ptestc.

ches@gcc.gnu.org > Subject: Re: [x86 PATCH] Convert ptestz of pandn into ptestc. > > On Tue, Jun 13, 2023 at 6:03 PM Roger Sayle > wrote: > > > > > > This patch is the next instalment in a set of backend patches around > > improvements to ptest/vptest. A previ

Re: [x86 PATCH] Convert ptestz of pandn into ptestc.

On Tue, Jun 13, 2023 at 6:03 PM Roger Sayle wrote: > > > This patch is the next instalment in a set of backend patches around > improvements to ptest/vptest. A previous patch optimized the sequence > t=pand(x,y); ptestz(t,t) into the equivalent ptestz(x,y), using the > property that ZF is set to

[x86 PATCH] Convert ptestz of pandn into ptestc.

This patch is the next instalment in a set of backend patches around improvements to ptest/vptest. A previous patch optimized the sequence t=pand(x,y); ptestz(t,t) into the equivalent ptestz(x,y), using the property that ZF is set to (X&Y) == 0. This patch performs a similar transformation, conv