------- Comment #5 from amodra at gmail dot com 2010-01-28 02:49 -------
OK, so at the time we call make_decl_rtl for mrSurfaceList::operator[]
(gdb) bt
#0 rs6000_elf_encode_section_info (decl=0x40402a00, rtl=0x404014a0, first=1)
at /home/alan/src/gcc/gcc/config/rs6000/rs6000.c:23487
#1 0x1082a4e4 in make_decl_rtl (decl=0x40402a00)
at /home/alan/src/gcc/gcc/varasm.c:1471
#2 0x1082b924 in notice_global_symbol (decl=0x40402a00)
at /home/alan/src/gcc/gcc/varasm.c:1628
#3 0x108839e8 in cgraph_mark_reachable_node (node=0x4035c1b0)
at /home/alan/src/gcc/gcc/cgraph.c:1479
#4 0x10889fd0 in cgraph_analyze_functions ()
at /home/alan/src/gcc/gcc/cgraphunit.c:980
#5 0x1088c250 in cgraph_finalize_compilation_unit ()
at /home/alan/src/gcc/gcc/cgraphunit.c:1073
#6 0x1012fbdc in cp_write_global_declarations ()
at /home/alan/src/gcc/gcc/cp/decl2.c:3780
we see these flags on the function decl:
addressable used public static weak autoinline decl_5
The weak flag makes default_binds_local_p decide that this is non-local so
doesn't set SYMBOL_REF_LOCAL_P on the rtl.
Later, here:
(gdb) bt
#0 cgraph_make_node_local (node=0x4035c1b0)
at /home/alan/src/gcc/gcc/cgraph.c:2157
#1 0x106e15e4 in modify_function () at /home/alan/src/gcc/gcc/tree-sra.c:3798
#2 ipa_early_sra () at /home/alan/src/gcc/gcc/tree-sra.c:3891
#3 0x1051f750 in execute_one_pass (pass=0x11045634)
at /home/alan/src/gcc/gcc/passes.c:1522
#4 0x1051fac4 in execute_pass_list (pass=0x11045634)
at /home/alan/src/gcc/gcc/passes.c:1577
#5 0x1051fadc in execute_pass_list (pass=0x11045470)
at /home/alan/src/gcc/gcc/passes.c:1578
#6 0x105221d4 in do_per_function_toporder (pass=0x11045408)
at /home/alan/src/gcc/gcc/passes.c:1120
#7 execute_ipa_pass_list (pass=0x11045408)
at /home/alan/src/gcc/gcc/passes.c:1759
#8 0x1088c034 in ipa_passes () at /home/alan/src/gcc/gcc/cgraphunit.c:1716
#9 cgraph_optimize () at /home/alan/src/gcc/gcc/cgraphunit.c:1775
#10 0x1088c25c in cgraph_finalize_compilation_unit ()
at /home/alan/src/gcc/gcc/cgraphunit.c:1082
#11 0x1012fbdc in cp_write_global_declarations ()
at /home/alan/src/gcc/gcc/cp/decl2.c:3780
a bunch of flags on the function decl are cleared, including the weak flag.
So rs6000_function_ok_for_sibcall quite happily says that a sibcall is OK,
***but the rtl flags have not been updated***.
In particular, SYMBOL_REF_LOCAL_P clear stops rs6000.md:sibcall_value_local32
from matching, and we try to use sibcall_value_nonlocal_sysv.
Seems to me that the rtl flags need updating in cgraph_make_node_local.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42344
