Re: [PATCH 0/4 v3] Fix PR/63679 when --param sra-max-scalarization-size specified

[Alan Lawrence <alan dot lawrence at foss dot arm dot com>]

On 21/12/15 13:13, Alan Lawrence wrote:
> This is a respin of previous patch series:
> https://gcc.gnu.org/ml/gcc-patches/2015-10/msg03271.html
> Minus three of the smaller patches having already been committed; with the
> updated version of the main patch to SRA; and the patches to DOM reworked
> to avoid constructing gimple stmt's.
>
> IMHO this feels quite invasive for stage 3, however, I note the PR/63679
> (ssa-dom-cse-2.c being XFAILed on a bunch of platforms, and currently still
> FAILing on ARM) is a regression from gcc 4.9.1. So I'd ask maintainer's thoughts
> as to whether we should take this patch set for gcc 6.

I've now tested the series on powerpc64-none-linux-gnu (gcc110) and 
powerpc64le-none-linux-gnu (gcc112).

On powerpc64le, this causes the same guality failures as on AArch64:
gcc.dg/guality/pr54970.c   -O1  line 15 a[0] == 1
gcc.dg/guality/pr54970.c   -O1  line 20 a[0] == 1
gcc.dg/guality/pr54970.c   -O1  line 25 a[0] == 1
and the same with other optimization flags. (I note that there are quite a lot 
of guality failures on both powerpc and also aarch64, which are generally not 
included in the posts on the gcc-testresults mailing list).

The same pr54970 tests still seem to pass on powerpc64 big-endian even with the 
patches.

On both powerpc64 and powerpc64le, the ssa-dom-cse-7.c test also fails, because 
the constant gets pushed to the constant pool :(, which was not the point of 
that test (I'd tried to construct it to test normalization of MEM_REFs in DOM 
prior to the SRA changes). So, adding --param 
sra-max-scalarization-size-Ospeed=32 fixes this once the SRA patch is in (!), or 
we could xfail on powerpc64*-*-*-*.

--Alan