sparc.md

gcc库的原代码,对编程有很大帮助.

;;- Machine description for SPARC chip for GNU C compiler
;;  Copyright (C) 1987, 88, 89, 92, 93, 94, 1995 Free Software Foundation, Inc.
;;  Contributed by Michael Tiemann ([e-mail])
;;  64 bit SPARC V9 support by Michael Tiemann, Jim Wilson, and Doug Evans,
;;  at Cygnus Support.

;; This file is part of GNU CC.

;; GNU CC is free software; you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation; either version 2, or (at your option)
;; any later version.

;; GNU CC is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;; GNU General Public License for more details.

;; You should have received a copy of the GNU General Public License
;; along with GNU CC; see the file COPYING.  If not, write to
;; the Free Software Foundation, 59 Temple Place - Suite 330,
;; Boston, MA 02111-1307, USA.

;;- See file "rtl.def" for documentation on define_insn, match_*, et. al.

;; The upper 32 fp regs on the v9 can't hold SFmode values.  To deal with this
;; a second register class, EXTRA_FP_REGS, exists for the v9 chip.  The name
;; is a bit of a misnomer as it covers all 64 fp regs.  The corresponding
;; constraint letter is 'e'.  To avoid any confusion, 'e' is used instead of
;; 'f' for all DF/TFmode values, including those that are specific to the v8.

;; Architecture type.  Arch32bit includes v7, sparclite, v8.

(define_attr "arch" "arch32bit,arch64bit"
  (const (symbol_ref "sparc_arch_type")))

;; CPU type. This is only used for instruction scheduling
(define_attr "cpu" "cypress,supersparc"
 (const
  (cond [(symbol_ref "TARGET_SUPERSPARC") (const_string "supersparc")]
	(const_string "cypress"))))

;; Insn type.  Used to default other attribute values.

;; type "unary" insns have one input operand (1) and one output operand (0)
;; type "binary" insns have two input operands (1,2) and one output (0)
;; type "compare" insns have one or two input operands (0,1) and no output
;; type "call_no_delay_slot" is a call followed by an unimp instruction.

(define_attr "type"
  "move,unary,binary,compare,load,store,ialu,shift,uncond_branch,branch,call,call_no_delay_slot,address,imul,fpload,fpstore,fp,fpcmp,fpmul,fpdivs,fpdivd,fpsqrt,cmove,multi,misc"
  (const_string "binary"))

;; Set true if insn uses call-clobbered intermediate register.
(define_attr "use_clobbered" "false,true"
  (if_then_else (and (eq_attr "type" "address")
		     (match_operand 0 "clobbered_register" ""))
	 	(const_string "true")
		(const_string "false")))

;; Length (in # of insns).
(define_attr "length" ""
  (cond [(eq_attr "type" "load,fpload")
	 (if_then_else (match_operand 1 "symbolic_memory_operand" "")
		       (const_int 2) (const_int 1))

	 (eq_attr "type" "store,fpstore")
	 (if_then_else (match_operand 0 "symbolic_memory_operand" "")
		       (const_int 2) (const_int 1))

	 (eq_attr "type" "address") (const_int 2)

	 (eq_attr "type" "binary")
	 (if_then_else (ior (match_operand 2 "arith_operand" "")
			    (match_operand 2 "arith_double_operand" ""))
		       (const_int 1) (const_int 3))

	 (eq_attr "type" "multi") (const_int 2)

	 (eq_attr "type" "move,unary")
	 (if_then_else (ior (match_operand 1 "arith_operand" "")
			    (match_operand 1 "arith_double_operand" ""))
		       (const_int 1) (const_int 2))]

	(const_int 1)))

(define_asm_attributes
  [(set_attr "length" "1")
   (set_attr "type" "multi")])

;; Attributes for instruction and branch scheduling

(define_attr "in_call_delay" "false,true"
  (cond [(eq_attr "type" "uncond_branch,branch,call,call_no_delay_slot,multi")
	 	(const_string "false")
	 (eq_attr "type" "load,fpload,store,fpstore")
	 	(if_then_else (eq_attr "length" "1")
			      (const_string "true")
			      (const_string "false"))
	 (eq_attr "type" "address")
	 	(if_then_else (eq_attr "use_clobbered" "false")
			      (const_string "true")
			      (const_string "false"))]
	(if_then_else (eq_attr "length" "1")
		      (const_string "true")
		      (const_string "false"))))

(define_delay (eq_attr "type" "call")
  [(eq_attr "in_call_delay" "true") (nil) (nil)])

;; ??? Should implement the notion of predelay slots for floating point
;; branches.  This would allow us to remove the nop always inserted before
;; a floating point branch.

;; ??? It is OK for fill_simple_delay_slots to put load/store instructions
;; in a delay slot, but it is not OK for fill_eager_delay_slots to do so.
;; This is because doing so will add several pipeline stalls to the path
;; that the load/store did not come from.  Unfortunately, there is no way
;; to prevent fill_eager_delay_slots from using load/store without completely
;; disabling them.  For the SPEC benchmark set, this is a serious lose,
;; because it prevents us from moving back the final store of inner loops.

(define_attr "in_branch_delay" "false,true"
  (if_then_else (and (eq_attr "type" "!uncond_branch,branch,call,call_no_delay_slot,multi")
		     (eq_attr "length" "1"))
		(const_string "true")
		(const_string "false")))

(define_attr "in_uncond_branch_delay" "false,true"
  (if_then_else (and (eq_attr "type" "!uncond_branch,branch,call,call_no_delay_slot,multi")
		     (eq_attr "length" "1"))
		(const_string "true")
		(const_string "false")))

(define_attr "in_annul_branch_delay" "false,true"
  (if_then_else (and (eq_attr "type" "!uncond_branch,branch,call,call_no_delay_slot,multi")
		     (eq_attr "length" "1"))
		(const_string "true")
		(const_string "false")))

(define_delay (eq_attr "type" "branch")
  [(eq_attr "in_branch_delay" "true")
   (nil) (eq_attr "in_annul_branch_delay" "true")])

(define_delay (eq_attr "type" "uncond_branch")
  [(eq_attr "in_uncond_branch_delay" "true")
   (nil) (nil)])
   
;; Function units of the SPARC

;; (define_function_unit {name} {num-units} {n-users} {test}
;;                       {ready-delay} {issue-delay} [{conflict-list}])

;; The integer ALU.
;; (Noted only for documentation; units that take one cycle do not need to
;; be specified.)

;; On the sparclite, integer multiply takes 1, 3, or 5 cycles depending on
;; the inputs.

;; (define_function_unit "alu" 1 0
;;  (eq_attr "type" "unary,binary,move,address") 1 0)

;; ---- cypress CY7C602 scheduling:
;; Memory with load-delay of 1 (i.e., 2 cycle load).
(define_function_unit "memory" 1 0 
  (and (eq_attr "type" "load,fpload") (eq_attr "cpu" "cypress")) 2 2)

;; SPARC has two floating-point units: the FP ALU,
;; and the FP MUL/DIV/SQRT unit.
;; Instruction timings on the CY7C602 are as follows
;; FABSs	4
;; FADDs/d	5/5
;; FCMPs/d	4/4
;; FDIVs/d	23/37
;; FMOVs	4
;; FMULs/d	5/7
;; FNEGs	4
;; FSQRTs/d	34/63
;; FSUBs/d	5/5
;; FdTOi/s	5/5
;; FsTOi/d	5/5
;; FiTOs/d	9/5

;; The CY7C602 can only support 2 fp isnsn simultaneously.
;; More insns cause the chip to stall.

(define_function_unit "fp_alu" 1 0
  (and (eq_attr "type" "fp")            (eq_attr "cpu" "cypress")) 5 5)
(define_function_unit "fp_mds" 1 0
  (and (eq_attr "type" "fpmul")         (eq_attr "cpu" "cypress")) 7 7)
(define_function_unit "fp_mds" 1 0
  (and (eq_attr "type" "fpdivs,fpdivd") (eq_attr "cpu" "cypress")) 37 37)
(define_function_unit "fp_mds" 1 0
  (and (eq_attr "type" "fpsqrt")        (eq_attr "cpu" "cypress")) 63 63)

;; ----- The TMS390Z55 scheduling
;; The Supersparc can issue 1 - 3 insns per cycle; here we assume
;; three insns/cycle, and hence multiply all costs by three.
;; Combinations up to two integer, one ld/st, one fp.
;; Memory delivers its result in one cycle to IU, zero cycles to FP
(define_function_unit "memory" 1 0
  (and (eq_attr "type" "load")          (eq_attr "cpu" "supersparc")) 3 3)
(define_function_unit "memory" 1 0
  (and (eq_attr "type" "fpload")        (eq_attr "cpu" "supersparc")) 1 3)
;; at least one in three instructions can be a mem opt.
(define_function_unit "memory" 1 0
  (and (eq_attr "type" "store,fpstore") (eq_attr "cpu" "supersparc")) 1 3)
;; at least one in three instructions can be a shift op.
(define_function_unit "shift" 1 0
  (and (eq_attr "type" "shift")         (eq_attr "cpu" "supersparc")) 1 3)

;; There are only two write ports to the integer register file
;; A store also uses a write port
(define_function_unit "iwport" 2 0
  (and (eq_attr "type" "load,store,shift,ialu") (eq_attr "cpu" "supersparc")) 1 3)

;; Timings; throughput/latency
;; FADD     1/3    add/sub, format conv, compar, abs, neg
;; FMUL     1/3
;; FDIVs    4/6
;; FDIVd    7/9
;; FSQRTs   6/8
;; FSQRTd  10/12
;; IMUL     4/4

(define_function_unit "fp_alu" 1 0
  (and (eq_attr "type" "fp,fpcmp") (eq_attr "cpu" "supersparc")) 9 3)
(define_function_unit "fp_mds" 1 0
  (and (eq_attr "type" "fpmul")    (eq_attr "cpu" "supersparc")) 9 3)
(define_function_unit "fp_mds" 1 0
  (and (eq_attr "type" "fpdivs")   (eq_attr "cpu" "supersparc")) 18 12)
(define_function_unit "fp_mds" 1 0
  (and (eq_attr "type" "fpdivd")   (eq_attr "cpu" "supersparc")) 27 21)
(define_function_unit "fp_mds" 1 0
  (and (eq_attr "type" "fpsqrt")   (eq_attr "cpu" "supersparc")) 36 30)
(define_function_unit "fp_mds" 1 0
  (and (eq_attr "type" "imul")     (eq_attr "cpu" "supersparc")) 12 12)

;; Compare instructions.
;; This controls RTL generation and register allocation.

;; We generate RTL for comparisons and branches by having the cmpxx 
;; patterns store away the operands.  Then, the scc and bcc patterns
;; emit RTL for both the compare and the branch.
;;
;; We do this because we want to generate different code for an sne and
;; seq insn.  In those cases, if the second operand of the compare is not
;; const0_rtx, we want to compute the xor of the two operands and test
;; it against zero.
;;
;; We start with the DEFINE_EXPANDs, then the DEFINE_INSNs to match
;; the patterns.  Finally, we have the DEFINE_SPLITs for some of the scc
;; insns that actually require more than one machine instruction.

;; Put cmpsi first among compare insns so it matches two CONST_INT operands.

(define_expand "cmpsi"
  [(set (reg:CC 0)
	(compare:CC (match_operand:SI 0 "register_operand" "")
		    (match_operand:SI 1 "arith_operand" "")))]
  ""
  "
{
  sparc_compare_op0 = operands[0];
  sparc_compare_op1 = operands[1];
  DONE;
}")

(define_expand "cmpdi"
  [(set (reg:CCX 0)
	(compare:CCX (match_operand:DI 0 "register_operand" "")
		     (match_operand:DI 1 "arith_double_operand" "")))]
  "TARGET_V9"
  "
{
  sparc_compare_op0 = operands[0];
  sparc_compare_op1 = operands[1];
  DONE;
}")

(define_expand "cmpsf"
  [(set (reg:CCFP 0)
	(compare:CCFP (match_operand:SF 0 "register_operand" "")
		      (match_operand:SF 1 "register_operand" "")))]
  "TARGET_FPU"
  "
{
  sparc_compare_op0 = operands[0];
  sparc_compare_op1 = operands[1];
  DONE;
}")

(define_expand "cmpdf"
  [(set (reg:CCFP 0)
	(compare:CCFP (match_operand:DF 0 "register_operand" "")
		      (match_operand:DF 1 "register_operand" "")))]
  "TARGET_FPU"
  "
{
  sparc_compare_op0 = operands[0];
  sparc_compare_op1 = operands[1];
  DONE;
}")

(define_expand "cmptf"
  [(set (reg:CCFP 0)
	(compare:CCFP (match_operand:TF 0 "register_operand" "")
		      (match_operand:TF 1 "register_operand" "")))]
  "TARGET_FPU"
  "
{
  sparc_compare_op0 = operands[0];
  sparc_compare_op1 = operands[1];
  DONE;
}")

;; Next come the scc insns.  For seq, sne, sgeu, and sltu, we can do this
;; without jumps using the addx/subx instructions.  For seq/sne on v9 we use
;; the same code as v8 (the addx/subx method has more applications).  The
;; exception to this is "reg != 0" which can be done in one instruction on v9
;; (so we do it).  For the rest, on v9 we use conditional moves; on v8, we do
;; branches.

;; Seq_special[_xxx] and sne_special[_xxx] clobber the CC reg, because they
;; generate addcc/subcc instructions.

(define_expand "seqsi_special"
  [(set (match_dup 3)
	(xor:SI (match_operand:SI 1 "register_operand" "")
		(match_operand:SI 2 "register_operand" "")))
   (parallel [(set (match_operand:SI 0 "register_operand" "")
		   (eq:SI (match_dup 3) (const_int 0)))
	      (clobber (reg:CC 0))])]
  ""
  "{ operands[3] = gen_reg_rtx (SImode); }")

(define_expand "seqdi_special"
  [(set (match_dup 3)
	(xor:DI (match_operand:DI 1 "register_operand" "")
		(match_operand:DI 2 "register_operand" "")))
   (parallel [(set (match_operand:DI 0 "register_operand" "")
		   (eq:DI (match_dup 3) (const_int 0)))
	      (clobber (reg:CCX 0))])]
  ""
  "{ operands[3] = gen_reg_rtx (DImode); }")

(define_expand "snesi_special"
  [(set (match_dup 3)
	(xor:SI (match_operand:SI 1 "register_operand" "")
		(match_operand:SI 2 "register_operand" "")))
   (parallel [(set (match_operand:SI 0 "register_operand" "")
		   (ne:SI (match_dup 3) (const_int 0)))
	      (clobber (reg:CC 0))])]
  ""
  "{ operands[3] = gen_reg_rtx (SImode); }")

(define_expand "snedi_special"
  [(set (match_dup 3)
	(xor:DI (match_operand:DI 1 "register_operand" "")
		(match_operand:DI 2 "register_operand" "")))
   (parallel [(set (match_operand:DI 0 "register_operand" "")
		   (ne:DI (match_dup 3) (const_int 0)))
	      (clobber (reg:CCX 0))])]
  ""
  "{ operands[3] = gen_reg_rtx (DImode); }")

(define_expand "seqdi_special_trunc"
  [(set (match_dup 3)
	(xor:DI (match_operand:DI 1 "register_operand" "")
		(match_operand:DI 2 "register_operand" "")))
   (parallel [(set (match_operand:SI 0 "register_operand" "")
		   (eq:SI (subreg:SI (match_dup 3) 0) (const_int 0)))
	      (clobber (reg:CC 0))])]
  ""
  "{ operands[3] = gen_reg_rtx (DImode); }")

(define_expand "snedi_special_trunc"
  [(set (match_dup 3)
	(xor:DI (match_operand:DI 1 "register_operand" "")
		(match_operand:DI 2 "register_operand" "")))
   (parallel [(set (match_operand:SI 0 "register_operand" "")
		   (ne:SI (subreg:SI (match_dup 3) 0) (const_int 0)))
	      (clobber (reg:CC 0))])]
  ""
  "{ operands[3] = gen_reg_rtx (DImode); }")

(define_expand "seqsi_special_extend"
  [(set (subreg:SI (match_dup 3) 0)
	(xor:SI (match_operand:SI 1 "register_operand" "")
		(match_operand:SI 2 "register_operand" "")))
   (parallel [(set (match_operand:DI 0 "register_operand" "")
		   (eq:DI (match_dup 3) (const_int 0)))
	      (clobber (reg:CCX 0))])]
  ""
  "{ operands[3] = gen_reg_rtx (DImode); }")

(define_expand "snesi_special_extend"
  [(set (subreg:SI (match_dup 3) 0)
	(xor:SI (match_operand:SI 1 "register_operand" "")
		(match_operand:SI 2 "register_operand" "")))
   (parallel [(set (match_operand:DI 0 "register_operand" "")
		   (ne:DI (match_dup 3) (const_int 0)))
	      (clobber (reg:CCX 0))])]
  ""
  "{ operands[3] = gen_reg_rtx (DImode); }")

;; ??? v9: Operand 0 needs a mode, so SImode was chosen.
;; However, the code handles both SImode and DImode.
(define_expand "seq"
  [(set (match_operand:SI 0 "intreg_operand" "")
	(eq:SI (match_dup 1) (const_int 0)))]
  ""
  "
{
  if (GET_MODE (sparc_compare_op0) == SImode)
    {
      rtx pat;