https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67850
Bug ID: 67850
Summary: Wrong call_used_regs used in aggregate_value_p
Product: gcc
Version: 6.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: middle-end
Assignee: unassigned at gcc dot gnu.org
Reporter: hjl.tools at gmail dot com
CC: julia.koval at intel dot com
Target Milestone: ---
aggregate_value_p may be called:
#0 aggregate_value_p (exp=0x7ffff7ff9258, fntype=0x7ffff150b0a8)
at /export/gnu/import/git/sources/gcc/gcc/function.c:2096
#1 0x0000000000e2d3ae in (anonymous namespace)::pass_nrv::execute (
this=0x2313730, fun=0x7ffff16091f8)
at /export/gnu/import/git/sources/gcc/gcc/tree-nrv.c:153
#2 0x0000000000c6c6ce in execute_one_pass (pass=0x2313730)
at /export/gnu/import/git/sources/gcc/gcc/passes.c:2342
#3 0x0000000000c6c918 in execute_pass_list_1 (pass=0x2313730)
at /export/gnu/import/git/sources/gcc/gcc/passes.c:2395
#4 0x0000000000c6c989 in execute_pass_list (fn=0x7ffff16091f8, pass=0x2310730)
at /export/gnu/import/git/sources/gcc/gcc/passes.c:2406
#5 0x00000000008f436c in cgraph_node::expand (this=0x7ffff160c170)
at /export/gnu/import/git/sources/gcc/gcc/cgraphunit.c:1983
#6 0x00000000008f49a6 in expand_all_functions ()
at /export/gnu/import/git/sources/gcc/gcc/cgraphunit.c:2119
#7 0x00000000008f54bf in symbol_table::compile (this=0x7ffff14e90a8)
at /export/gnu/import/git/sources/gcc/gcc/cgraphunit.c:2472
#8 0x00000000008f56e0 in symbol_table::finalize_compilation_unit (
this=0x7ffff14e90a8)
at /export/gnu/import/git/sources/gcc/gcc/cgraphunit.c:2562
#9 0x0000000000d6a287 in compile_file ()
(gdb) f 1
#1 0x0000000000e2d3ae in (anonymous namespace)::pass_nrv::execute (
this=0x2313730, fun=0x7ffff16091f8)
at /export/gnu/import/git/sources/gcc/gcc/tree-nrv.c:153
153 if (!aggregate_value_p (result, current_function_decl))
(gdb)
But the wrong call_used_regs may be used here:
regno = REGNO (reg);
nregs = hard_regno_nregs[regno][TYPE_MODE (type)];
for (i = 0; i < nregs; i++)
if (! call_used_regs[regno + i])
return 1;
since targetm.expand_to_rtl_hook may be called to switch ABI:
(gdb) bt
#0 ix86_maybe_switch_abi ()
at /export/gnu/import/git/sources/gcc/gcc/config/i386/i386.c:7445
#1 0x00000000008b0e6f in (anonymous namespace)::pass_expand::execute (
this=0x2313850, fun=0x7ffff16090a8)
at /export/gnu/import/git/sources/gcc/gcc/cfgexpand.c:6153
#2 0x0000000000c6c6ce in execute_one_pass (pass=0x2313850)
at /export/gnu/import/git/sources/gcc/gcc/passes.c:2342
#3 0x0000000000c6c918 in execute_pass_list_1 (pass=0x2313850)
at /export/gnu/import/git/sources/gcc/gcc/passes.c:2395
#4 0x0000000000c6c989 in execute_pass_list (fn=0x7ffff16090a8, pass=0x2310730)
at /export/gnu/import/git/sources/gcc/gcc/passes.c:2406
#5 0x00000000008f436c in cgraph_node::expand (this=0x7ffff160c000)
at /export/gnu/import/git/sources/gcc/gcc/cgraphunit.c:1983
#6 0x00000000008f49a6 in expand_all_functions ()
at /export/gnu/import/git/sources/gcc/gcc/cgraphunit.c:2119
#7 0x00000000008f54bf in symbol_table::compile (this=0x7ffff14e90a8)
at /export/gnu/import/git/sources/gcc/gcc/cgraphunit.c:2472
#8 0x00000000008f56e0 in symbol_table::finalize_compilation_unit (
this=0x7ffff14e90a8)
at /export/gnu/import/git/sources/gcc/gcc/cgraphunit.c:2562
#9 0x0000000000d6a287 in compile_file ()
to change call_used_regs.
