Re: [PATCH v6 00/13] s390x/tcg: Implement Vector-Enhancements Facility 2

[Thomas Huth]

On 03/05/2022 16.42, David Miller wrote:
> Sorry,  It was in the discussion for v4 patches,  as an attachment .
> mail thread:
> [PATCH v4 10/11] tests/tcg/s390x: Tests for Vector Enhancements Facility 2
> So it likely never made it to the mailing list.
>
> I've reattached and will forward the patch (by itself) to the mailing list.
>
> I think the other solution works just as well by ignoring if compiler
> doesn't support z15.
>
> I just thought I'd bring it back up as I saw discussion about it.

Ok, I now gave this a try ... and while this should now work fine with older 
versions of gcc/binutils, it's failing with Clang now:

  BUILD   s390x-linux-user guest-tests
/home/thuth/devel/qemu/tests/tcg/s390x/vxeh2_vs.c:14:18: error: couldn't 
allocate output register for constraint 'v'
    asm volatile(".insn vrr, 0xE70000000074, %[v1], %[v2], %[v3], 0,0,0\n"
                 ^
/home/thuth/devel/qemu/tests/tcg/s390x/vxeh2_vs.c:22:18: error: couldn't 
allocate output register for constraint 'v'
    asm volatile(".insn vrr, 0xE7000000007E, %[v1], %[v2], %[v3], 0,0,0\n"
                 ^
/home/thuth/devel/qemu/tests/tcg/s390x/vxeh2_vs.c:30:18: error: couldn't 
allocate output register for constraint 'v'
    asm volatile(".insn vrr, 0xE7000000007C, %[v1], %[v2], %[v3], 0,0,0\n"
                 ^
/home/thuth/devel/qemu/tests/tcg/s390x/vxeh2_vs.c:40:18: error: couldn't 
allocate output register for constraint 'v'
    asm volatile(".insn vrr, 0xE70000000086, %[v1], %[v2], %[v3], 0, %[I], 0\n"
                 ^
/home/thuth/devel/qemu/tests/tcg/s390x/vxeh2_vs.c:51:18: error: couldn't 
allocate output register for constraint 'v'
    asm volatile(".insn vrr, 0xE70000000087, %[v1], %[v2], %[v3], 0, %[I], 0\n"
                 ^
5 errors generated.
make[1]: *** [../Makefile.target:109: vxeh2_vs] Error 1
make[1]: *** Waiting for unfinished jobs....
/home/thuth/devel/qemu/tests/tcg/s390x/vxeh2_vcvt.c:14:18: error: couldn't 
allocate output register for constraint 'v'
    asm volatile(".insn vrr, 0xE700000000C3, %[v1], %[v2], 0, %[m3], %[m4], 
%[m5]\n"
                 ^
/home/thuth/devel/qemu/tests/tcg/s390x/vxeh2_vcvt.c:25:18: error: couldn't 
allocate output register for constraint 'v'
    asm volatile(".insn vrr, 0xE700000000C1, %[v1], %[v2], 0, %[m3], %[m4], 
%[m5]\n"
                 ^
/home/thuth/devel/qemu/tests/tcg/s390x/vxeh2_vcvt.c:36:18: error: couldn't 
allocate output register for constraint 'v'
    asm volatile(".insn vrr, 0xE700000000C2, %[v1], %[v2], 0, %[m3], %[m4], 
%[m5]\n"
                 ^
/home/thuth/devel/qemu/tests/tcg/s390x/vxeh2_vcvt.c:47:18: error: couldn't 
allocate output register for constraint 'v'
    asm volatile(".insn vrr, 0xE700000000C0, %[v1], %[v2], 0, %[m3], %[m4], 
%[m5]\n"
                 ^
4 errors generated.

...

Thus I think I'll rather go with the other approach instead that checks for 
the availability of -march=z15.

 Thomas