Richard Biener wrote:
> 
> I have posted 5 patches as part of a larger series to merge
> (parts) from the match-and-simplify branch.  While I think
> there was overall consensus that the idea behind the project
> is sound there are technical questions left for how the
> thing should look in the end.  I've raised them in 3/n
> which is the only patch of the series that contains any
> patterns sofar.
> 
> To re-iterate here (as I expect most people will only look
> at [0/n] patches ;)), the question is whether we are fine
> with making fold-const (thus fold_{unary,binary,ternary})
> not handle some cases it handles currently.

I have tested on aarch64 all the code in the match-and-simplify against trunk as
of the last merge at r216315:

2014-10-16  Richard Biener  <rguent...@suse.de>

        Merge from trunk r216235 through r216315.

Overall, I see a lot of perf regressions (about 2/3 of the tests) than
improvements (1/3 of the tests).  I will try to reduce tests.

For instance, saxpy regresses at -O3 on aarch64:

void saxpy(double* x, double* y, double* z) {
    int i=0;
    for (i = 0 ; i < ARRAY_SIZE; i++) {
        z[i] = x[i] + scalar*y[i];
    }
}

$ diff -u base.s mas.s
--- base.s      2014-10-16 15:30:15.351430000 -0500
+++ mas.s       2014-10-16 15:30:16.183035000 -0500
@@ -2,12 +2,14 @@
        add     x1, x2, 800
        ldr     q0, [x0, x2]
        add     x3, x2, 1600
+       cmp     x0, 784
        ldr     q1, [x0, x1]
+       add     x1, x0, 16
        fmla    v0.2d, v1.2d, v2.2d
        str     q0, [x0, x3]
-       add     x0, x0, 16
-       cmp     x0, 800
+       mov     x0, x1
        bne     .L140
 .LBE179:
-       subs    w4, w4, #1
+       cmp     w4, 1
+       sub     w4, w4, #1
        bne     .L139



Thanks,
Sebastian

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