https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84753
--- Comment #3 from Jeffrey Walton <noloader at gmail dot com> ---
(In reply to Jeffrey Walton from comment #2)
> (In reply to Bill Schmidt from comment #1)
> > GCC 4.8.5 is out of service. This is fixed in all in-service versions of
> > GCC (6.4 and later).
>
> Interesting. I'm seeing it in GCC 7.2.0. Are you certain of this?
Here's an example to make sure we are on the same page.
$ /opt/cfarm/gcc-latest/bin/g++ --version
g++ (GCC) 7.2.0
$ /opt/cfarm/gcc-latest/bin/g++ -g3 -O3 -Wall -DTEST_MAIN -mcpu=power8
sha256-p8.cxx -o sha256-p8.exe
$ objdump --disassemble sha256-p8.exe | c++filt
0000000010000880 <SHA256_SCHEDULE(unsigned int*, unsigned char const*)>:
10000880: 03 10 40 3c lis r2,4099
10000884: 00 81 42 38 addi r2,r2,-32512
10000888: f0 ff c1 fb std r30,-16(r1)
1000088c: f8 ff e1 fb std r31,-8(r1)
10000890: fe ff 22 3d addis r9,r2,-2
10000894: 10 00 c4 3b addi r30,r4,16
10000898: 70 8e 29 39 addi r9,r9,-29072
1000089c: 10 00 e3 3b addi r31,r3,16
100008a0: 20 00 84 39 addi r12,r4,32
100008a4: 20 00 63 39 addi r11,r3,32
100008a8: 99 4e 00 7c lxvd2x vs32,0,r9
100008ac: 30 00 a3 38 addi r5,r3,48
100008b0: 40 00 23 39 addi r9,r3,64
100008b4: c4 ff c0 38 li r6,-60
100008b8: c0 ff e0 38 li r7,-64
100008bc: 99 26 20 7c lxvd2x vs33,0,r4
100008c0: 30 00 84 38 addi r4,r4,48
100008c4: f8 ff 00 39 li r8,-8
100008c8: e4 ff 40 39 li r10,-28
100008cc: 57 02 00 f0 xxswapd vs32,vs32
100008d0: 57 0a 21 f0 xxswapd vs33,vs33
100008d4: 97 05 00 f0 xxlnand vs32,vs32,vs32
100008d8: 2b 08 21 10 vperm v1,v1,v1,v0
100008dc: 57 0a 21 f0 xxswapd vs33,vs33
100008e0: 99 1f 20 7c stxvd2x vs33,0,r3
100008e4: 18 00 60 38 li r3,24
100008e8: a6 03 69 7c mtctr r3
100008ec: 99 f6 20 7c lxvd2x vs33,0,r30
100008f0: 57 0a 21 f0 xxswapd vs33,vs33
100008f4: 2b 08 21 10 vperm v1,v1,v1,v0
100008f8: 57 0a 21 f0 xxswapd vs33,vs33
100008fc: 99 ff 20 7c stxvd2x vs33,0,r31
10000900: 99 66 20 7c lxvd2x vs33,0,r12
10000904: 57 0a 21 f0 xxswapd vs33,vs33
10000908: 2b 08 21 10 vperm v1,v1,v1,v0
1000090c: 57 0a 21 f0 xxswapd vs33,vs33
10000910: 99 5f 20 7c stxvd2x vs33,0,r11
10000914: 99 26 20 7c lxvd2x vs33,0,r4
10000918: 57 0a 21 f0 xxswapd vs33,vs33
1000091c: 2b 08 01 10 vperm v0,v1,v1,v0
10000920: 57 02 00 f0 xxswapd vs32,vs32
10000924: 99 2f 00 7c stxvd2x vs32,0,r5
10000928: 00 00 00 60 nop
1000092c: 00 00 42 60 ori r2,r2,0
10000930: 99 36 09 7c lxvd2x vs32,r9,r6
10000934: 99 3e 89 7d lxvd2x vs44,r9,r7
10000938: 99 56 a9 7d lxvd2x vs45,r9,r10
1000093c: 99 46 29 7c lxvd2x vs33,r9,r8
10000940: 82 06 00 10 vshasigmaw v0,v0,0,0
10000944: 82 7e 21 10 vshasigmaw v1,v1,0,15
10000948: 80 60 00 10 vadduwm v0,v0,v12
1000094c: 80 68 00 10 vadduwm v0,v0,v13
10000950: 80 08 00 10 vadduwm v0,v0,v1
10000954: 99 4f 00 7c stxvd2x vs32,0,r9
10000958: 08 00 29 39 addi r9,r9,8
1000095c: d4 ff 00 42 bdnz 10000930 <SHA256_SCHEDULE(unsigned
int*, unsigned char const*)+0xb0>
10000960: f0 ff c1 eb ld r30,-16(r1)
10000964: f8 ff e1 eb ld r31,-8(r1)
10000968: 20 00 80 4e blr
1000096c: 00 00 00 00 .long 0x0
10000970: 00 09 00 00 .long 0x900
10000974: 00 02 00 00 attn
10000978: 00 00 00 60 nop
1000097c: 00 00 42 60 ori r2,r2,0
