------- Comment #4 from law at redhat dot com 2010-05-11 05:31 -------
I doubt my work will make a significant difference for this test.
We're trying to reload an insn which matches:
(define_insn "*add<mode>3_cconly_overflow"
[(set (reg:CCC FLAGS_REG)
(compare:CCC
(plus:SWI
(match_operand:SWI 1 "nonimmediate_operand" "%0")
(match_operand:SWI 2 "<general_operand>" "<r><i>m"))
(match_dup 1)))
(clobber (match_scratch:SWI 0 "=<r>"))]
"ix86_binary_operator_ok (PLUS, <MODE>mode, operands)"
"add{<imodesuffix>}\t{%2, %0|%0, %2}"
[(set_attr "type" "alu")
(set_attr "mode" "<MODE>")])
(gdb) p debug_reload()
Reload 0: reload_in (SI) = (reg:SI 6 bp)
reload_out (SI) = (scratch:SI)
GENERAL_REGS, RELOAD_OTHER (opnum = 0), can't combine
reload_in_reg: (subreg:SI (reg:DI 6 bp [orig:66 D.2764 ] [66]) 0)
reload_out_reg: (scratch:SI)
$14 = void
(gdb) p debug_rtx (insn)
(insn 25 24 26 5 j.c:26 (parallel [
(set (reg:CCC 17 flags)
(compare:CCC (plus:SI (subreg:SI (reg:DI 6 bp [orig:66 D.2764 ]
[66]) 0)
(reg:SI 3 bx [orig:58 D.2737 ] [58]))
(subreg:SI (reg:DI 6 bp [orig:66 D.2764 ] [66]) 0)))
(clobber (scratch:SI))
]) 316 {*addsi3_cconly_overflow} (expr_list:REG_DEAD (reg:DI 6 bp
[orig:66 D.2764 ] [66])
(expr_list:REG_DEAD (reg:SI 3 bx [orig:58 D.2737 ] [58])
(nil))))
I think the only way to satisfy this reload is to allocate the scratch to
(subreg: SI (reg:DI 6)) I have no clue why reload doesn't do that.
--
law at redhat dot com changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |law at redhat dot com
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44031
