https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97098
Bug ID: 97098
Summary: vect_bb_slp_mark_live_stmts() loops forever on test
case using -O3
Product: gcc
Version: 11.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: bergner at gcc dot gnu.org
Target Milestone: ---
Created attachment 49237
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=49237&action=edit
preprocessed test case
GCC trunk hangs on the attached test case (from OpenMP) when compiling with -O3
(powerpc64le-linux). Compiling with -O2 is fine.
Using the debugger and breaking into the compile multiple times, the compiler
always has the following backtrace:
(gdb) c
Continuing.
^C
Program received signal SIGINT, Interrupt.
0x0000000011813e54 in link_use_stmts_after (head=0x7ffff5c40448,
imm=0x7fffffff5c20)
at /home/bergner/gcc/gcc-fsf-mainline-mma/gcc/ssa-iterators.h:908
908 FOR_EACH_SSA_USE_OPERAND (use_p, head_stmt, op_iter, flag)
(gdb) bt
#0 0x0000000011813e54 in link_use_stmts_after (head=0x7ffff5c40448,
imm=0x7fffffff5c20)
at /home/bergner/gcc/gcc-fsf-mainline-mma/gcc/ssa-iterators.h:908
#1 0x000000001181413c in next_imm_use_stmt (imm=0x7fffffff5c20) at
/home/bergner/gcc/gcc-fsf-mainline-mma/gcc/ssa-iterators.h:961
#2 0x00000000118223a4 in vect_bb_slp_mark_live_stmts (bb_vinfo=0x133aae60,
node=0x136955f0, instance=0x133a1830, cost_vec=0x133a1858,
svisited=...) at
/home/bergner/gcc/gcc-fsf-mainline-mma/gcc/tree-vect-slp.c:3107
#3 0x0000000011822464 in vect_bb_slp_mark_live_stmts (bb_vinfo=0x133aae60,
node=0x13695660, instance=0x133a1830, cost_vec=0x133a1858,
svisited=...) at
/home/bergner/gcc/gcc-fsf-mainline-mma/gcc/tree-vect-slp.c:3128
#4 0x0000000011822464 in vect_bb_slp_mark_live_stmts (bb_vinfo=0x133aae60,
node=0x136956d0, instance=0x133a1830, cost_vec=0x133a1858,
svisited=...) at
/home/bergner/gcc/gcc-fsf-mainline-mma/gcc/tree-vect-slp.c:3128
#5 0x0000000011822464 in vect_bb_slp_mark_live_stmts (bb_vinfo=0x133aae60,
node=0x13695740, instance=0x133a1830, cost_vec=0x133a1858,
svisited=...) at
/home/bergner/gcc/gcc-fsf-mainline-mma/gcc/tree-vect-slp.c:3128
#6 0x0000000011822464 in vect_bb_slp_mark_live_stmts (bb_vinfo=0x133aae60,
node=0x13695820, instance=0x133a1830, cost_vec=0x133a1858,
svisited=...) at
/home/bergner/gcc/gcc-fsf-mainline-mma/gcc/tree-vect-slp.c:3128
#7 0x0000000011822464 in vect_bb_slp_mark_live_stmts (bb_vinfo=0x133aae60,
node=0x13695890, instance=0x133a1830, cost_vec=0x133a1858,
svisited=...) at
/home/bergner/gcc/gcc-fsf-mainline-mma/gcc/tree-vect-slp.c:3128
#8 0x0000000011822464 in vect_bb_slp_mark_live_stmts (bb_vinfo=0x133aae60,
node=0x1369a1f0, instance=0x133a1830, cost_vec=0x133a1858,
svisited=...) at
/home/bergner/gcc/gcc-fsf-mainline-mma/gcc/tree-vect-slp.c:3128
#9 0x0000000011822464 in vect_bb_slp_mark_live_stmts (bb_vinfo=0x133aae60,
node=0x1369a2d0, instance=0x133a1830, cost_vec=0x133a1858,
svisited=...) at
/home/bergner/gcc/gcc-fsf-mainline-mma/gcc/tree-vect-slp.c:3128
#10 0x0000000011822464 in vect_bb_slp_mark_live_stmts (bb_vinfo=0x133aae60,
node=0x1369a340, instance=0x133a1830, cost_vec=0x133a1858,
svisited=...) at
/home/bergner/gcc/gcc-fsf-mainline-mma/gcc/tree-vect-slp.c:3128
...
