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reload question
- From: Alex Turjan <aturjan at yahoo dot com>
- To: gcc at gcc dot gnu dot org
- Date: Wed, 23 Jun 2010 10:22:30 -0700 (PDT)
- Subject: reload question
Hi,
My port supports hardware loops generated by the following (do_end) pattern:
(set (pc) (if_then_else (ne (match_operand:HI 0 "general_register_operand" "d")
(const_int 0))
(label_ref (match_operand 1 "" ""))
(pc)))
(set (match_operand:HI 2 "general_register_operand" "=0")
(plus:HI (match_operand:HI 3 "general_register_operand" "0")
(const_int -1)))
(clobber (match_operand:BI 4 "predicate_register_operand" "=j"))
When Im compiling a loop with high register pressure the register allocator does not allocate a register for the loop counter (i.e., operand 0) as it has a long life range. Thus operand 0 has to be reloaded but then I get a failure in the reload:
error: unable to generate reloads for:
(jump_insn 211 182 188 11 lib5.c:51 (parallel [
(set (pc)
(if_then_else (ne (reg:HI 292 [ N ])
(const_int 0 [0x0]))
(label_ref 183)
(pc)))
(set (reg:HI 292 [ N ])
(plus:HI (reg:HI 292 [ N ])
(const_int -1 [0xffffffffffffffff])))
(clobber (reg:BI 33 p1 [293]))
]) 506 {do_endhi} (expr_list:REG_UNUSED (reg:BI 33 p1 [293])
(expr_list:REG_BR_PROB (const_int 9100 [0x238c])
(nil)))
-> 183)
lib5.c:105:1: internal compiler error: in find_reloads, at reload.c:3821
Can anybody give me a hint?
I am aware of the following msg:
http://gcc.gnu.org/ml/gcc/2001-09/msg00942.html
but still dont know how to make reload do the work.
thanks,
Alex