https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88134
--- Comment #22 from rguenther at suse dot de <rguenther at suse dot de> --- On Fri, 21 Dec 2018, asolokha at gmx dot com wrote: > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88134 > > --- Comment #21 from Arseny Solokha <asolokha at gmx dot com> --- > (In reply to Arseny Solokha from comment #13) > > In decl_address_invariant_p() we hit this break: > > > > 3423 case VAR_DECL: > > 3424 if ((TREE_STATIC (op) || DECL_EXTERNAL (op)) > > 3425 || DECL_THREAD_LOCAL_P (op) > > 3426 || DECL_CONTEXT (op) == current_function_decl > > 3427 || decl_function_context (op) == current_function_decl) > > 3428 return true; > > 3429 break; > > > > and return false, which in the end becomes what is_gimple_min_invariant() > > returns. > > Indeed, w/ -ftrapping-math we have this at the point of the (failing) > assertion: > > (gdb) p debug_tree (currop->op0) > <addr_expr 0x7ffff78a0f60 > type <pointer_type 0x7ffff77cf888 > type <real_type 0x7ffff77cf498 double DF > size <integer_cst 0x7ffff77c8000 constant 64> > unit-size <integer_cst 0x7ffff77c8018 constant 8> > align:64 warn_if_not_align:0 symtab:0 alias-set 1 canonical-type > 0x7ffff77cf498 precision:64 > pointer_to_this <pointer_type 0x7ffff77cf888>> > public unsigned SI > size <integer_cst 0x7ffff77b6f90 constant 32> > unit-size <integer_cst 0x7ffff77b6fa8 constant 4> > align:32 warn_if_not_align:0 symtab:0 alias-set -1 canonical-type > 0x7ffff77cf888> > > arg:0 <var_decl 0x7ffff7fcf5a0 D.1473 type <real_type 0x7ffff77cf498 > double> > addressable used ignored read DF gcpt737x.c:9:5 size <integer_cst > 0x7ffff77c8000 64> unit-size <integer_cst 0x7ffff77c8018 8> > align:64 warn_if_not_align:0 context <function_decl 0x7ffff78a5c00 > i6>>> > $1 = void > > while w/ -fno-trapping-math: > > (gdb) p debug_tree (currop->op0) > <addr_expr 0x7ffff78cf0c0 > type <pointer_type 0x7ffff77cf888 > type <real_type 0x7ffff77cf498 double DF > size <integer_cst 0x7ffff77c8000 constant 64> > unit-size <integer_cst 0x7ffff77c8018 constant 8> > align:64 warn_if_not_align:0 symtab:0 alias-set 1 canonical-type > 0x7ffff77cf498 precision:64 > pointer_to_this <pointer_type 0x7ffff77cf888>> > public unsigned SI > size <integer_cst 0x7ffff77b6f90 constant 32> > unit-size <integer_cst 0x7ffff77b6fa8 constant 4> > align:32 warn_if_not_align:0 symtab:0 alias-set 2 canonical-type > 0x7ffff77cf888> > > arg:0 <var_decl 0x7ffff7fcf6c0 D.1480 type <real_type 0x7ffff77cf498 > double> > addressable used ignored DF gcpt737x.c:9:5 size <integer_cst > 0x7ffff77c8000 64> unit-size <integer_cst 0x7ffff77c8018 8> > align:64 warn_if_not_align:0>> > $1 = void > > There's no function context in the latter case, so > > 3427 || decl_function_context (op) == current_function_decl) > > evaluates to false, and gcc_assert() eventually fails. > > In case of -fno-trapping-math this context gets assigned during the second > call > to gimple_add_tmp_var(): > > 751 DECL_CONTEXT (tmp) = current_function_decl; > 752 DECL_SEEN_IN_BIND_EXPR_P (tmp) = 1; > > and I fail to see why this doesn't happen w/ -ftrapping-math. The assignment > clearly happens on the second invocation of gimple_add_tmp_var() but > watchpoint > doesn't fire. > > -fno-trapping-math: > > Breakpoint 1, gimple_add_tmp_var (tmp=0x7ffff7fcf510) > at gcc/tree.h:3270 > (gdb) > Continuing. > > Hardware watchpoint 3: -location DECL_CONTEXT (tmp) > > Old value = (tree_node *) 0x0 > New value = (tree_node *) 0x7ffff78a5c00 > gimple_add_tmp_var (tmp=0x7ffff7fcf510) > at gcc/gimplify.c:752 > > (gdb) > Continuing. > > Breakpoint 1, gimple_add_tmp_var (tmp=0x7ffff7fcf5a0) > at gcc/tree.h:3270 > > (gdb) > Continuing. > > Hardware watchpoint 4: -location TREE_OPERAND (currop->op0, > 0).decl_minimal.context > > Old value = (tree_node *) 0x0 > New value = (tree_node *) 0x7ffff78a5c00 > gimple_add_tmp_var (tmp=0x7ffff7fcf5a0) > at gcc/gimplify.c:752 > > (gdb) > Continuing. > > Breakpoint 1, gimple_add_tmp_var (tmp=0x7ffff7fcf630) > at gcc/tree.h:3270 > > (gdb) > Continuing. > > Breakpoint 2, create_component_ref_by_pieces_1 (block=0x7ffff78a3888, > ref=0x1e4d090, operand=0x7fffffffc7d0, stmts=0x7fffffffc868) > at gcc/tree-ssa-pre.c:2520 > > (gdb) > Continuing. > [Inferior 1 (process 4261) exited normally] > > -ftrapping-math: > > Breakpoint 1, gimple_add_tmp_var (tmp=0x7ffff7fcf510) > at gcc/tree.h:3270 > > (gdb) > Continuing. > > Hardware watchpoint 3: -location DECL_CONTEXT (tmp) > > Old value = (tree_node *) 0x0 > New value = (tree_node *) 0x7ffff78a5c00 > gimple_add_tmp_var (tmp=0x7ffff7fcf510) > at gcc/gimplify.c:752 > > (gdb) > Continuing. > > Breakpoint 1, gimple_add_tmp_var (tmp=0x7ffff7fcf5a0) > at gcc/tree.h:3270 > > (gdb) > Continuing. > > Breakpoint 1, gimple_add_tmp_var (tmp=0x7ffff7fcf630) > at gcc/tree.h:3270 > > (gdb) > Continuing. > > Breakpoint 2, create_component_ref_by_pieces_1 (block=0x7ffff78a3138, > ref=0x1e4cb40, operand=0x7fffffffc960, stmts=0x7fffffffc9f8) > at gcc/tree-ssa-pre.c:2520 > > (gdb) > Continuing. > during GIMPLE pass: pre > cptctz2r.c: In function 'i6': > cptctz2r.c:4:1: internal compiler error: in create_component_ref_by_pieces_1, > at tree-ssa-pre.c:2520 > > What should I look at next? Where do the vars get created from? (backtrace from the gimple_add_tmp_var places?)
