https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79963
Bug ID: 79963
Summary: vec_eq_any extracts wrong CR bit when compiling with
-mcpu=power9
Product: gcc
Version: 7.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: target
Assignee: unassigned at gcc dot gnu.org
Reporter: acsawdey at gcc dot gnu.org
CC: meissner at gcc dot gnu.org, wschmidt at gcc dot gnu.org
Target Milestone: ---
Target: powerpc64*-*-* power9
Tested with trunk 245979:
gcc/xgcc -Bgcc ../trunk/gcc/testsuite/gcc.target/powerpc/altivec-12.c -maltivec
-lm -g -o ./altivec-12.exe
In test testsuite/gcc.target/powerpc/altivec-12.c line 50:
CHECK_IF (vec_any_eq (h, addf1));
For power9 we generate this code:
.L17:
.loc 1 50 0 is_stmt 1
addis 9,2,.LC1@toc@ha
ld 9,.LC1@toc@l(9)
lxv 12,0(9)
addis 9,2,addf1@toc@ha
addi 9,9,addf1@toc@l
lxv 0,0(9)
xvcmpeqsp. 0,12,0
mfcr 9,2
rlwinm 9,9,25,1
xori 9,9,0x1
extsw 9,9
cmpdi 7,9,0
bne 7,.L18
.loc 1 50 0 is_stmt 0 discriminator 1
bl abort
In gdb I can see that h and addf1 are equal after loading, and the comparison
is correct, however we are extracting the wrong bit from the cr with the
rlwinm.
For power8 we generate this code:
.L17:
.loc 1 50 0 is_stmt 1
addis 9,2,.LC1@toc@ha
ld 9,.LC1@toc@l(9)
lxvd2x 0,0,9
xxpermdi 12,0,0,2
addis 9,2,addf1@toc@ha
addi 9,9,addf1@toc@l
lxvd2x 0,0,9
xxpermdi 0,0,0,2
xvcmpeqsp. 0,12,0
mfcr 9,2
rlwinm 9,9,27,1
xori 9,9,0x1
extsw 9,9
cmpdi 7,9,0
bne 7,.L18
.loc 1 50 0 is_stmt 0 discriminator 1
bl abort
which runs correctly.
