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sign_extended 32bit -addition
- From: "Sivaprasad.pv" <sivaprasad dot pv at redpinesignals dot com>
- To: gcc <gcc-help at gcc dot gnu dot org>
- Date: Wed, 30 Jan 2008 11:15:55 +0530
- Subject: sign_extended 32bit -addition
Hi all,
Our target supports 'addm op1,op2' instruction which perform following
operation.
op2=sign_extend(op1)+op2
where 'op1' is 16bit integer operand and 'op2' is 32bit integer
operand.before performing addition 'op1' is sign_extended to 32 bit
number and then perform addition with 'op2' and store the result in 'op2'.
I have added new pattern in md file as below.
(define_insn "*addsihi5"
[(set (match_operand:SI 0 "register_operand" "=D")
(plus:SI (match_operand:SI 1 "register_operand" "0")
(sign_extend:SI (match_operand:HI 2 "register_operand" "e"))))]
""
"addm %2,%0"
[(set_attr "type" "binary")])
But compiler generating following patterns independently:
(insn 13 12 14 (nil) (set (reg:SI 25)
(sign_extend:SI (reg:HI 26))) -1 (nil)
(nil))
(insn 15 14 16 (nil) (set (reg:SI 28)
(plus:SI (reg:SI 27)
(reg:SI 25))) -1 (nil)
(nil))
How can i make compiler to generate required pattern so that it can
generate addm instruction instead of sign_extend & addition instructions
independently.
Can u please help me in this regard.
--P.V. Siva prasad