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Problem with modyfying "addsi3" in machine description
- From: Tomasz Jankowski <tomcioj at gmail dot com>
- To: gcc-help at gcc dot gnu dot org
- Date: Fri, 12 Oct 2012 17:04:48 +0200
- Subject: Problem with modyfying "addsi3" in machine description
Hello,
I'm working on machine description for modified OpenRISC and at the
moment I'm trying to modify standard "addsi3" insn. I have custom add
in instruction called "radd", which I'm going to use for regular
arithmetic (for computing addresses, offsets for stack pointer etc. I
use "standard" OpenRISC instructions). The problem with "radd" is only
operates on register, so when I have to add immediate to register I
have to first manually copy immediate to temporary register and then
call my "radd" instruction. I implemented code for that:
(define_expand "addsi3"
[(set (match_operand:SI 0 "general_operand" "")
(plus:SI (match_operand:SI 1 "general_operand" "")
(match_operand:SI 2 "general_operand" "")))]
""
{
if (CONST_INT_P (operands [2]))
{
operands [2] = force_reg (SImode, operands [2]);
emit_insn (gen_rto (operands [2], operands [2]));
}
//emit_insn (gen_rtx_SET (VOIDmode, operands [0], gen_rtx_PLUS
(SImode, operands [1], operands [2])));
DONE;
})
(define_insn "radd"
[(set (match_operand:SI 0 "register_operand" "=r")
(plus:SI (match_operand:SI 1 "register_operand" "%r")
(match_operand:SI 2 "register_operand" "r")))]
""
"l.radd \t%0,%1,%2"
[(set_attr "type" "add")
(set_attr "length" "1")])
During GCC compilation, when self test are run GCC fails on assertion:
gcc_assert (can_create_pseudo_p ());
in function:
rtx gen_reg_rtx (enum machine_mode mode)
Why I cannot create temporary registers in define_expand? What's
possible workaround for this issue?
Bye