http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59763
Bug ID: 59763
Summary: ICE in dwarf2out_frame_debug_expr, at dwarf2cfi.c:1550
with -mno-accumulate-outgoing-args
Product: gcc
Version: unknown
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: rtl-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: ubizjak at gmail dot com
Following testcase:
--cut here--
extern void abort(void);
register long *B asm ("ebp");
int main()
{
abort();
return 0;
}
--cut here--
ICEs with -mno-accumulate-outgoing-args on 32bit and 64bit x86 targets, when
preferred stack boundary is larger than the word size (2 for 32bit and 4 for
64bit targets) Please note that default stack boundary is set to 4 by default,
so the ICE triggers even without -mpreferred-stack-boundary option.
-m32 -mno-accumulate-outgoing-args
t.c: In function ‘main’:
t.c:9:1: internal compiler error: in dwarf2out_frame_debug_expr, at
dwarf2cfi.c:1550
}
^
0x6c5cd3 dwarf2out_frame_debug_expr
/home/uros/gcc-svn/trunk/gcc/dwarf2cfi.c:1548
0x6c6133 dwarf2out_frame_debug
/home/uros/gcc-svn/trunk/gcc/dwarf2cfi.c:2043
0x6c6133 scan_insn_after
/home/uros/gcc-svn/trunk/gcc/dwarf2cfi.c:2369
0x6c7fd3 scan_trace
/home/uros/gcc-svn/trunk/gcc/dwarf2cfi.c:2526
0x6c8a92 create_cfi_notes
/home/uros/gcc-svn/trunk/gcc/dwarf2cfi.c:2565
0x6c8a92 execute_dwarf2_frame
/home/uros/gcc-svn/trunk/gcc/dwarf2cfi.c:2925
0x6c8a92 execute
/home/uros/gcc-svn/trunk/gcc/dwarf2cfi.c:3421
Please submit a full bug report,
...
-m64 -mno-accumulate-outgoing-args -mpreferred-stack-boundary=5
t.c: In function ‘main’:
t.c:9:1: internal compiler error: in dwarf2out_frame_debug_expr, at
dwarf2cfi.c:1550
}
^
0x6c5cd3 dwarf2out_frame_debug_expr
/home/uros/gcc-svn/trunk/gcc/dwarf2cfi.c:1548
0x6c6133 dwarf2out_frame_debug
/home/uros/gcc-svn/trunk/gcc/dwarf2cfi.c:2043
0x6c6133 scan_insn_after
/home/uros/gcc-svn/trunk/gcc/dwarf2cfi.c:2369
0x6c7fd3 scan_trace
/home/uros/gcc-svn/trunk/gcc/dwarf2cfi.c:2526
0x6c8a92 create_cfi_notes
/home/uros/gcc-svn/trunk/gcc/dwarf2cfi.c:2565
0x6c8a92 execute_dwarf2_frame
/home/uros/gcc-svn/trunk/gcc/dwarf2cfi.c:2925
0x6c8a92 execute
/home/uros/gcc-svn/trunk/gcc/dwarf2cfi.c:3421
Please submit a full bug report,
...
(gdb) up
#2 0x00000000006c5cd4 in dwarf2out_frame_debug_expr
(expr=expr@entry=0x7ffff19c8eb8) at
/home/uros/gcc-svn/trunk/gcc/dwarf2cfi.c:1548
1548 gcc_assert (!fixed_regs [REGNO (dest)]
(gdb) p debug_rtx (dest)
(reg/f:DI 6 bp)
$3 = void
(gdb) p debug_rtx(expr)
(set (reg/f:DI 6 bp)
(reg/f:DI 7 sp))
$4 = void
(gdb) list
1543 cur_trace->cfa_temp.offset = cur_cfa->offset;
1544 }
1545 else
1546 {
1547 /* Saving a register in a register. */
1548 gcc_assert (!fixed_regs [REGNO (dest)]
1549 /* For the SPARC and its register window. */
1550 || (dwf_regno (src) ==
DWARF_FRAME_RETURN_COLUMN));
1551
1552 /* After stack is aligned, we can only save SP in FP
The problem is that compiler emits the frame for main(), even when
-fomit-frame-pointer is active (the default for 64bit and 32bit targets).
(insn/f 16 3 17 2 (set (reg:DI 39 r10)
(plus:DI (reg/f:DI 7 sp)
(const_int 8 [0x8]))) t.c:6 259 {*leadi}
(nil))
(insn/f 17 16 18 2 (parallel [
(set (reg/f:DI 7 sp)
(and:DI (reg/f:DI 7 sp)
(const_int -32 [0xffffffffffffffe0])))
(clobber (reg:CC 17 flags))
]) t.c:6 400 {*anddi_1}
(nil))
(insn/f 18 17 19 2 (set (mem:DI (pre_dec:DI (reg/f:DI 7 sp)) [0 S8 A8])
(mem/c:DI (plus:DI (reg:DI 39 r10)
(const_int -8 [0xfffffffffffffff8])) [0 S8 A8])) t.c:6 65
{*pushdi2_rex64}
(nil))
(insn/f 19 18 20 2 (set (mem:DI (pre_dec:DI (reg/f:DI 7 sp)) [0 S8 A8])
(reg/f:DI 6 bp)) t.c:6 65 {*pushdi2_rex64}
(nil))
(insn/f 20 19 21 2 (set (reg/f:DI 6 bp)
(reg/f:DI 7 sp)) t.c:6 89 {*movdi_internal}
(nil))
(insn/f 21 20 22 2 (set (mem:DI (pre_dec:DI (reg/f:DI 7 sp)) [0 S8 A8])
(reg:DI 39 r10)) t.c:6 65 {*pushdi2_rex64}
(nil))
(insn/f 22 21 23 2 (parallel [
(set (reg/f:DI 7 sp)
(plus:DI (reg/f:DI 7 sp)
(const_int -8 [0xfffffffffffffff8])))
(clobber (reg:CC 17 flags))
(clobber (mem:BLK (scratch) [0 A8]))
]) t.c:6 969 {pro_epilogue_adjust_stack_di_add}
(nil))
The compiler trips on a frame-related (insn/f 20), where fixed reg (bp) is
touched. So, is it really necessary to emit frame-reg setup for main, even with
-fomit-frame-pointer?
This problem is the cause of the gcc.target/i386/pr9771-1.c testsuite failure
[1] when the compiler defaults to -march=corei7.
[1] http://gcc.gnu.org/ml/gcc-testresults/2014-01/msg00720.html
