https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69899
--- Comment #5 from Arseny Solokha <asolokha at gmx dot com> ---
I believe practically all gcc branches, the current gcc-11.0.1-alpha20210314
snapshot (g:c2d7c39fcb8a3cb67600cdb6fde49ecb0e951589) included, demonstrate the
same issue on
gcc/testsuite/gcc.target/s390/vector/long-double-asm-commutative.c w/ -O1
-ffinite-math-only:
% x86_64-unknown-linux-gnu-gcc-11.0.1 -O1 -ffinite-math-only -c
gcc/testsuite/gcc.target/s390/vector/long-double-asm-commutative.c
gcc/testsuite/gcc.target/s390/vector/long-double-asm-commutative.c: In function
'main':
gcc/testsuite/gcc.target/s390/vector/long-double-asm-commutative.c:11:3: error:
output constraint 0 must specify a single register
11 | asm("lxr\t%0,%1\n"
| ^~~
during RTL pass: stack
gcc/testsuite/gcc.target/s390/vector/long-double-asm-commutative.c:16:1:
internal compiler error: in replace_reg, at reg-stack.c:714
16 | }
| ^
0x6b654d replace_reg
/var/tmp/portage/sys-devel/gcc-11.0.1_alpha20210314/work/gcc-11-20210314/gcc/reg-stack.c:714
0xd6e91b compare_for_stack_reg
/var/tmp/portage/sys-devel/gcc-11.0.1_alpha20210314/work/gcc-11-20210314/gcc/reg-stack.c:1379
0xd6e91b subst_stack_regs_pat
/var/tmp/portage/sys-devel/gcc-11.0.1_alpha20210314/work/gcc-11-20210314/gcc/reg-stack.c:2001
0xd6f212 subst_stack_regs
/var/tmp/portage/sys-devel/gcc-11.0.1_alpha20210314/work/gcc-11-20210314/gcc/reg-stack.c:2444
0xd6f418 convert_regs_1
/var/tmp/portage/sys-devel/gcc-11.0.1_alpha20210314/work/gcc-11-20210314/gcc/reg-stack.c:3080
0xd6f418 convert_regs_2
/var/tmp/portage/sys-devel/gcc-11.0.1_alpha20210314/work/gcc-11-20210314/gcc/reg-stack.c:3214
0xd704c8 convert_regs
/var/tmp/portage/sys-devel/gcc-11.0.1_alpha20210314/work/gcc-11-20210314/gcc/reg-stack.c:3249
0xd704c8 reg_to_stack
/var/tmp/portage/sys-devel/gcc-11.0.1_alpha20210314/work/gcc-11-20210314/gcc/reg-stack.c:3374
0xd704c8 rest_of_handle_stack_regs
/var/tmp/portage/sys-devel/gcc-11.0.1_alpha20210314/work/gcc-11-20210314/gcc/reg-stack.c:3429
0xd704c8 execute
/var/tmp/portage/sys-devel/gcc-11.0.1_alpha20210314/work/gcc-11-20210314/gcc/reg-stack.c:3461
