https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89313
Bug ID: 89313
Summary: [9 Regression] ICE in process_alt_operands, at
lra-constraints.c:2962
Product: gcc
Version: 9.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c
Assignee: unassigned at gcc dot gnu.org
Reporter: gs...@t-online.de
Target Milestone: ---
Changed between 20180930 and 20181007 :
$ cat z1.c
long f (long a);
long g (void)
{
register long z asm ("rax");
asm ("foo %0, %1, %1" : "=&r" (z) : "r" (f), "0" (f));
return z;
}
$ gcc-9-20190210 -c z1.c -O0
z1.c: Assembler messages:
z1.c:5: Error: no such instruction: `foo %rax,%rdx,%rdx'
$ gcc-9-20190210 -c z1.c -O2
z1.c: In function 'g':
z1.c:7:1: error: unable to generate reloads for impossible constraints:
7 | }
| ^
(insn 7 16 15 2 (parallel [
(set (reg/v:DI 0 ax [ z ])
(asm_operands:DI ("foo %0, %1, %1") ("=&r") 0 [
(reg/v:DI 0 ax [ z ]) repeated x2
]
[
(asm_input:DI ("r") z1.c:5)
(asm_input:DI ("0") z1.c:5)
]
[] z1.c:5))
(clobber (reg:CC 17 flags))
]) "z1.c":5:3 -1
(expr_list:REG_UNUSED (reg:CC 17 flags)
(nil)))
during RTL pass: reload
z1.c:7:1: internal compiler error: in process_alt_operands, at
lra-constraints.c:2962
0x5aa7c0 _fatal_insn(char const*, rtx_def const*, char const*, int, char
const*)
../../gcc/rtl-error.c:108
0x93ac40 process_alt_operands
../../gcc/lra-constraints.c:2961
0x93d4bb curr_insn_transform
../../gcc/lra-constraints.c:3922
0x93fe8e lra_constraints(bool)
../../gcc/lra-constraints.c:4942
0x92e454 lra(_IO_FILE*)
../../gcc/lra.c:2461
0x8e9ff1 do_reload
../../gcc/ira.c:5516
0x8e9ff1 execute
../../gcc/ira.c:5700
