https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95636
Bug ID: 95636
Summary: ICE in sched2: internal compiler error: in
create_block_for_bookkeeping, at sel-sched.c:4549
Product: gcc
Version: 11.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: target
Assignee: unassigned at gcc dot gnu.org
Reporter: qianchao9 at huawei dot com
Target Milestone: ---
There exists a ICE on AArch64 when using GCC11.
Compiling this with -fsel-sched-pipelining -fselective-scheduling2
-fvar-tracking-assignments -Os:
typedef long unsigned int size_t;
extern volatile int chk_calls;
volatile char *s2 = "defg";
volatile size_t l1 = 1;
long buf1[64];
char *buf2 = (char *) (buf1 + 32);
void
__attribute__((noinline))
test3 (void)
{
struct A { char buf1[10]; char buf2[10]; } a;
char *r;
char buf3[20];
int i;
r = buf3;
for (i = 0; i < 2; ++i)
{
if (i == l1 + 1)
r = &a.buf1[1];
else if (i == l1)
r = &a.buf2[7];
else if (i == l1 + 1)
r = &buf3[5];
else if (i == l1 + 2)
r = &a.buf1[9];
}
__builtin___memcpy_chk (r, s2, l1, __builtin_object_size (r, 0));
if (chk_calls != 5){
abort ();
}
}
gives:
during RTL pass: sched2
testcase.c:32:1: internal compiler error: in create_block_for_bookkeeping, at
sel-sched.c:4549
32 | }
| ^
0xd4e55b create_block_for_bookkeeping
../../gcc/sel-sched.c:4549
0xd4e55b find_place_for_bookkeeping
../../gcc/sel-sched.c:4686
0xd4e55b generate_bookkeeping_insn
../../gcc/sel-sched.c:4786
0xd4e55b move_op_at_first_insn
../../gcc/sel-sched.c:6063
0xd4eca7 code_motion_path_driver
../../gcc/sel-sched.c:6657
0xd4f123 code_motion_process_successors
../../gcc/sel-sched.c:6342
0xd4f123 code_motion_path_driver
../../gcc/sel-sched.c:6608
0xd4f123 code_motion_process_successors
../../gcc/sel-sched.c:6342
0xd4f123 code_motion_path_driver
../../gcc/sel-sched.c:6608
0xd4f123 code_motion_process_successors
../../gcc/sel-sched.c:6342
0xd4f123 code_motion_path_driver
../../gcc/sel-sched.c:6608
0xd4fd4b move_op
../../gcc/sel-sched.c:6702
0xd4fd4b move_exprs_to_boundary
../../gcc/sel-sched.c:5223
0xd4fd4b schedule_expr_on_boundary
../../gcc/sel-sched.c:5436
0xd53af7 fill_insns
../../gcc/sel-sched.c:5578
0xd55713 schedule_on_fences
../../gcc/sel-sched.c:7353
0xd55713 sel_sched_region_2
../../gcc/sel-sched.c:7491
0xd56743 sel_sched_region_1
../../gcc/sel-sched.c:7533
0xd57bf7 sel_sched_region(int)
../../gcc/sel-sched.c:7634
0xd5855f run_selective_scheduling()
../../gcc/sel-sched.c:7720
during sched2 pass, we get bb:
(code_label 181 191 180 15 11 (nil) [2 uses])
(note 180 181 194 15 [bb 15] NOTE_INSN_BASIC_BLOCK)
(debug_insn 194 180 193 15 (var_location:SI i (plus:SI (reg:SI 1 x1 [orig:103
ivtmp.11 ] [103])
(const_int 1 [0x1]))) -1
(nil))
gcc/cfgrtl.c (rtl_split_block) tries to splits that bb to
(code_label 181 191 180 15 11 (nil) [2 uses])
(note 180 181 205 15 [bb 15] NOTE_INSN_BASIC_BLOCK)
and new_bb:
(note 205 180 194 20 [bb 20] NOTE_INSN_BASIC_BLOCK)
(debug_insn 194 205 204 20 (var_location:SI i (plus:SI (reg:SI 1 x1 [orig:103
ivtmp.11 ] [103])
(const_int 1 [0x1]))) -1
(nil))
(note 204 194 193 20 NOTE_INSN_DELETED)
Although new_bb contained only debug insns, we will swap the block numbers of
new_bb and single_succ(new_bb). So NOTE_INSN_DELETED note emited by
gcc/cfgrtl.c (rtl_split_block) is unnecessary here.
the following fixes the latent bug - we delete new_bb's NOTE_INSN_DELETED note
diff --git a/gcc/haifa-sched.c b/gcc/haifa-sched.c
index 80687fb5359..6dece11bf0c 100644
--- a/gcc/haifa-sched.c
+++ b/gcc/haifa-sched.c
@@ -9158,7 +9158,12 @@ sched_split_block_1 (basic_block first_bb, rtx after)
/* sched_split_block emits note if *check == BB_END. Probably it
is better to rip that note off. */
- return e->dest;
+ basic_block new_bb = e->dest;
+ rtx_insn *last_insn = BB_END (e->dest);
+ if (NOTE_P (last_insn) && NOTE_KIND (last_insn) == NOTE_INSN_DELETED)
+ delete_insn (last_insn);
+
+ return new_bb;
}
Bootstrap and tested on aarch64 platform. No new regression witnessed.
Any suggestions?
