; cpu description for debugging and experimental purposes. -*- Scheme -*-
; This file is part of CGEN.
; See file COPYING.CGEN for details.
; Copyright (C) 2000 Red Hat, Inc.
;
; This file is for experimental purposes.  Don't expect it to be correct
; or up to date.

(include "simplify.inc")

(define-arch
  (name play) ; name of cpu
  (comment "experimental .cpu file")
  (insn-lsb0? #f)
  (machs playb)
  (isas play)
)

(define-isa
  (name play)
  (base-insn-bitsize 16)
  (decode-assist (0 1 2 3))
)
  
(define-cpu
  (name cpuf)
  (comment "experimental cpu family")
  (endian little)
  (word-bitsize 32)
)

(define-mach
  (name playb)
  (comment "experimental mach")
  (cpu cpuf)
)

(define-model
  (name test) (comment "test") (attrs)
  (mach playb)
  ;(pipeline all "" () ((fetch) (decode) (execute) (writeback)))
  (unit u-exec "Execution Unit" () 1 1
	() () () ())
)

; Instruction fields.

(dnf f-op1       "op1"                 () 0 4)
(dnf f-op2       "op2"                 () 4 4)
(dnf f-op3       "op3"                 () 8 4)
(dnf f-op4       "op4"                 () 12 4)
(dnf f-r1        "r1"                  () 8 4)
(dnf f-r2        "r2"                  () 12 4)
(df  f-simm16     "simm16"             () 16 16 INT #f #f)

(define-normal-insn-enum insn-op1 "insn format enums" () OP1_ f-op1
  (.map .str (.iota 16))
)

(define-normal-insn-enum insn-op2 "insn format enums (2)" () OP2_ f-op2
  (.map .str (.iota 16))
)

(define-normal-insn-enum insn-op3 "insn format enums (3)" () OP3_ f-op3
  (.map .str (.iota 16))
)

(define-normal-insn-enum insn-op4 "insn format enums (4)" () OP4_ f-op4
  (.map .str (.iota 16))
)

; Hardware.

(dnh h-pc "program counter" (PC PROFILE) (pc) () () ())

(define-hardware
  (name h-gr)
  (comment "general registers")
  (attrs PROFILE );CACHE-ADDR)
  (type register WI (16))
  (indices keyword ""
	   ( (fp 13) (lr 14) (sp 15)
	     (r0 0) (r1 1) (r2 2) (r3 3) (r4 4) (r5 5) (r6 6) (r7 7)
	     (r8 8) (r9 9) (r10 10) (r11 11) (r12 12) (r13 13) (r14 14) (r15 15)
	     ))
)

(define-hardware
  (name h-status)
  (comment "status reg")
  (type register SI)
  (get () (const 0))
  (set (newval) (nop))
)

; These bits are actualy part of the PS register
(dsh h-nbit "negative bit" () (register BI))
(dsh h-zbit "zero     bit" () (register BI))
(dsh h-vbit "overflow bit" () (register BI))
(dsh h-cbit "carry    bit" () (register BI))

(dsh h-df "df test" () (register DF))
(dsh h-tf "tf test" () (register TF))

; Operand attributes.

(define-attr
  (for operand)
  (type boolean)
  (name HASH-PREFIX)
  (comment "immediates have a '#' prefix")
)

; Operands.

(dnop nbit "negative bit" (SEM-ONLY) h-nbit f-nil)
(dnop vbit "overflow bit" (SEM-ONLY) h-vbit f-nil)
(dnop zbit "zero     bit" (SEM-ONLY) h-zbit f-nil)
(dnop cbit "carry    bit" (SEM-ONLY) h-cbit f-nil)

(dnop dr     "destination register"    () h-gr   f-r1)
(dnop sr     "source register"         () h-gr   f-r2)
(dnop simm-16 "16 bit signed immediate" (HASH-PREFIX) h-sint f-simm16)

; Note that `df' doesn't work as that is a pmacro.
(dnop df-reg "df reg" () h-df f-nil)
(dnop tf-reg "tf reg" () h-tf f-nil)

; Instructions.

(dni add "add"
     ()
     "add $dr,$sr"
     (+ OP1_4 OP2_0 dr sr)
     (sequence ()
	       (set vbit (add-oflag dr sr (const 0)))
	       (set cbit (add-cflag dr sr (const 0)))
	       (set dr (add dr sr))
	       (set zbit (zflag dr))
	       (set nbit (nflag dr)))
     ()
)

(dni addv2 "add version 2"
     ()
     "add $dr,$sr"
     (+ OP1_4 OP2_1 dr sr)
     (sequence ((WI tmp1))
	       (parallel ()
			 (set tmp1 (add dr sr))
			 (set vbit (add-oflag dr sr (const 0)))
			 (set cbit (add-cflag dr sr (const 0))))
	       (set zbit (zflag tmp1))
	       (set nbit (nflag tmp1))
	       (set dr tmp1)
	       )
     ()
)

(dni addi "addi"
     ()
     "addi $dr,$sr,$simm-16"
     (+ OP1_4 OP2_2 dr sr simm-16)
     (set dr (add sr simm-16))
     ()
)

(define-pmacro (reg+ oprnd n)
  (reg h-gr (add (index-of oprnd) (const n)))
)

(dni ldm "ldm"
     ()
     "ldm $dr,$sr"
     (+ OP1_5 OP2_2 dr sr)
     (sequence ()
	       (set dr sr)
	       (set (reg+ dr 1) (reg+ sr 1))
	       )
     ()
)

(dni use-ifield "use-ifield"
     ()
     "foo $dr,$sr"
     (+ OP1_5 OP2_3 dr sr)
     (sequence ()
	       (set dr (ifield f-r2))
	       )
     ()
)

(dni use-index-of "index-of"
     ()
     "index-of $dr,$sr"
     (+ OP1_5 OP2_4 dr sr)
     (set dr (reg h-gr (add (index-of sr) (const 1))))
     ()
)

(dni load-df "use df"
     ()
     "load-df df,[$sr]"
     (+ OP1_6 OP2_0 OP3_0 sr)
     (set df-reg (mem DF sr))
     ()
)

(dni make-df "use df"
     ()
     "make-df df,[$sr]"
     (+ OP1_6 OP2_1 OP3_0 sr)
     (set df-reg (join DF SI (mem SI sr) (mem SI (add sr (const 4)))))
     ()
)

(dni split-df "use df"
     ()
     "split-df df,[$sr]"
     (+ OP1_6 OP2_2 OP3_0 sr)
     (sequence ((DF temp))
	       (set temp df-reg)
	       (set (concat (SI SI)
			     sr
			     (reg h-gr (add (regno sr) (const 1))))
		    (split DF SI temp))
	       )
     ()
)

(dni load-tf "use tf"
     ()
     "load-tf tf,[$sr]"
     (+ OP1_6 OP2_3 OP3_0 sr)
     (set tf-reg (mem TF sr))
     ()
)

(dni make-tf "use tf"
     ()
     "make-tf tf,[$sr]"
     (+ OP1_6 OP2_4 OP3_0 sr)
     (set tf-reg (join TF SI
		    sr
		    (reg h-gr (add (regno sr) (const 1)))
		    (reg h-gr (add (regno sr) (const 2)))
		    (reg h-gr (add (regno sr) (const 3)))))
     ()
)

(dni split-tf "use tf"
     ()
     "split-tf tf,[$sr]"
     (+ OP1_6 OP2_5 OP3_0 sr)
     (sequence ((TF temp))
	       (set temp tf-reg)
	       (set (concat (SI SI SI SI)
			     sr
			     (reg h-gr (add (regno sr) (const 1)))
			     (reg h-gr (add (regno sr) (const 2)))
			     (reg h-gr (add (regno sr) (const 3))))
		    (split TF SI temp))
	       )
     ()
)