M32C vs PR tree-optimization/39233

[DJ Delorie <dj at redhat dot com>]

As of this fix (yes, I know it was some time ago - I've been busy),
the m32c-elf build fails building the target libiberty:

./cc1 -fpreprocessed regex.i -quiet -dumpbase regex.c -mcpu=m32cm \
-auxbase-strip regex.o -g -O2 -W -Wall -Wwrite-strings -Wc++-compat \
-Wstrict-prototypes -pedantic -version -o regex.s


In file included from ../../../../gcc/libiberty/regex.c:639:
../../../../gcc/libiberty/regex.c: In function 'byte_re_match_2_internal':
../../../../gcc/libiberty/regex.c:7481: internal compiler error: in gen_add2_insn, at optabs.c:4733
Please submit a full bug report,
with preprocessed source if appropriate.
See <http://gcc.gnu.org/bugs.html> for instructions.
cc1.r144405.20090224-060515 - failed

The problem is, you *can't* treat pointers and integers the same on
m32c, as there is no integral type (16-bit? 32?) the same size as a
pointer (24 bits).  Pointer math and pointer compatisons need to be
done with pointer types.

[ gdb ] where
#0  fancy_abort (file=0x87e22a8 "../../gcc/gcc/optabs.c", line=4746, 
    function=0x87e28c9 "gen_add2_insn") at ../../gcc/gcc/diagnostic.c:724
#1  0x0837ddc5 in gen_add2_insn (x=0xb7993bb0, y=0xb7993b80) at ../../gcc/gcc/optabs.c:4745
#2  0x083f9df7 in gen_reload (out=0xb7993bb0, in=0xb7d086a8, opnum=0, type=RELOAD_FOR_INPUT)
    at ../../gcc/gcc/reload1.c:8248
#3  0x083fa959 in emit_input_reload_insns () at ../../gcc/gcc/reload1.c:7217
#4  do_input_reload (chain=<value optimized out>, rl=0x8896fcc, j=1)
    at ../../gcc/gcc/reload1.c:7511
#5  0x083ff278 in emit_reload_insns () at ../../gcc/gcc/reload1.c:7702
#6  reload_as_needed (live_known=1) at ../../gcc/gcc/reload1.c:4217
#7  0x084040f9 in reload (first=0xb7c8cd80, global=1) at ../../gcc/gcc/reload1.c:1169
#8  0x0832f799 in ira (f=<value optimized out>) at ../../gcc/gcc/ira.c:3239
#9  0x08331b50 in rest_of_handle_ira () at ../../gcc/gcc/ira.c:3309
#10 0x08396aed in execute_one_pass (pass=0x884a200) at ../../gcc/gcc/passes.c:1290
#11 0x08396d5c in execute_pass_list (pass=0x884a200) at ../../gcc/gcc/passes.c:1339
#12 0x08396d6f in execute_pass_list (pass=0x886bce0) at ../../gcc/gcc/passes.c:1340
#13 0x084aca80 in tree_rest_of_compilation (fndecl=0xb7fb5400) at ../../gcc/gcc/tree-optimize.c:437
#14 0x0860d3e2 in cgraph_expand_function (node=0xb7e84680) at ../../gcc/gcc/cgraphunit.c:1048
#15 0x0860f23f in cgraph_expand_all_functions () at ../../gcc/gcc/cgraphunit.c:1107
#16 cgraph_optimize () at ../../gcc/gcc/cgraphunit.c:1312
#17 0x080a5c0b in c_write_global_declarations () at ../../gcc/gcc/c-decl.c:8174
#18 0x0845817b in compile_file () at ../../gcc/gcc/toplev.c:989
#19 do_compile () at ../../gcc/gcc/toplev.c:2243
#20 toplev_main (argc=20, argv=0xbffff974) at ../../gcc/gcc/toplev.c:2278
#21 0x081266e2 in main (argc=Cannot access memory at address 0x23
) at ../../gcc/gcc/main.c:35

[ gdb ] call debug_reload(rl)
Reload 0: reload_in (HI) = (reg:HI 377 [ D.9641 ])
        A_REGS, RELOAD_FOR_INPUT_ADDRESS (opnum = 0)
        reload_in_reg: (reg:HI 377 [ D.9641 ])
        reload_reg_rtx: (reg:HI 4 a0)
Reload 1: reload_in (PSI) = (plus:PSI (reg:HI 377 [ D.9641 ])
                                                    (const_int 4 [0x4]))
        A_REGS, RELOAD_FOR_INPUT (opnum = 0), inc by 4
        reload_in_reg: (plus:PSI (reg:HI 377 [ D.9641 ])
                                                    (const_int 4 [0x4]))
        reload_reg_rtx: (reg:PSI 4 a0)
Reload 2: reload_in (PSI) = (mem/f:PSI (reg/f:PSI 5 a1 [995]) [7 S4 A8])
        A_HI_MEM_REGS, RELOAD_FOR_INPUT (opnum = 1), optional
        reload_in_reg: (mem/f:PSI (reg/f:PSI 5 a1 [995]) [7 S4 A8])


Note "(plus:PSI (reg:HI) (const_int))" - the mode conflict between PSI
and HI causes problems.

Can we somehow make this fix contingent on ports that have suitable
integral modes?