vm.lisp

开源跨平台Lisp编译器

;;;; miscellaneous VM definition noise for the x86-64

;;;; This software is part of the SBCL system. See the README file for
;;;; more information.
;;;;
;;;; This software is derived from the CMU CL system, which was
;;;; written at Carnegie Mellon University and released into the
;;;; public domain. The software is in the public domain and is
;;;; provided with absolutely no warranty. See the COPYING and CREDITS
;;;; files for more information.

(in-package "SB!VM")

;;; the size of an INTEGER representation of a SYSTEM-AREA-POINTER, i.e.
;;; size of a native memory address
(deftype sap-int () '(unsigned-byte 64))

;;;; register specs

(eval-when (:compile-toplevel :load-toplevel :execute)
  (defvar *byte-register-names* (make-array 32 :initial-element nil))
  (defvar *word-register-names* (make-array 16 :initial-element nil))
  (defvar *dword-register-names* (make-array 16 :initial-element nil))
  (defvar *qword-register-names* (make-array 32 :initial-element nil))
  (defvar *float-register-names* (make-array 16 :initial-element nil)))

(macrolet ((defreg (name offset size)
             (let ((offset-sym (symbolicate name "-OFFSET"))
                   (names-vector (symbolicate "*" size "-REGISTER-NAMES*")))
               `(progn
                  (eval-when (:compile-toplevel :load-toplevel :execute)
                    ;; EVAL-WHEN is necessary because stuff like #.EAX-OFFSET
                    ;; (in the same file) depends on compile-time evaluation
                    ;; of the DEFCONSTANT. -- AL 20010224
                    (def!constant ,offset-sym ,offset))
                  (setf (svref ,names-vector ,offset-sym)
                        ,(symbol-name name)))))
           ;; FIXME: It looks to me as though DEFREGSET should also
           ;; define the related *FOO-REGISTER-NAMES* variable.
           (defregset (name &rest regs)
             `(eval-when (:compile-toplevel :load-toplevel :execute)
                (defparameter ,name
                  (list ,@(mapcar (lambda (name)
                                    (symbolicate name "-OFFSET"))
                                  regs))))))

  ;; byte registers
  ;;
  ;; Note: the encoding here is different than that used by the chip.
  ;; We use this encoding so that the compiler thinks that AX (and
  ;; EAX) overlap AL and AH instead of AL and CL.
  ;;
  ;; High-byte are registers disabled on AMD64, since they can't be
  ;; encoded for an op that has a REX-prefix and we don't want to
  ;; add special cases into the code generation. The overlap doesn't
  ;; therefore exist anymore, but the numbering hasn't been changed
  ;; to reflect this.
  (defreg al    0 :byte)
  (defreg cl    2 :byte)
  (defreg dl    4 :byte)
  (defreg bl    6 :byte)
  (defreg sil  12 :byte)
  (defreg dil  14 :byte)
  (defreg r8b  16 :byte)
  (defreg r9b  18 :byte)
  (defreg r10b 20 :byte)
  (defreg r11b 22 :byte)
  (defreg r12b 24 :byte)
  (defreg r13b 26 :byte)
  (defreg r14b 28 :byte)
  (defreg r15b 30 :byte)
  (defregset *byte-regs*
      al cl dl bl sil dil r8b r9b r10b
      #+nil r11b #+nil r12b r13b r14b r15b)

  ;; word registers
  (defreg ax 0 :word)
  (defreg cx 2 :word)
  (defreg dx 4 :word)
  (defreg bx 6 :word)
  (defreg sp 8 :word)
  (defreg bp 10 :word)
  (defreg si 12 :word)
  (defreg di 14 :word)
  (defregset *word-regs* ax cx dx bx si di)

  ;; double word registers
  (defreg eax 0 :dword)
  (defreg ecx 2 :dword)
  (defreg edx 4 :dword)
  (defreg ebx 6 :dword)
  (defreg esp 8 :dword)
  (defreg ebp 10 :dword)
  (defreg esi 12 :dword)
  (defreg edi 14 :dword)
  (defregset *dword-regs* eax ecx edx ebx esi edi)

  ;; quadword registers
  (defreg rax 0 :qword)
  (defreg rcx 2 :qword)
  (defreg rdx 4 :qword)
  (defreg rbx 6 :qword)
  (defreg rsp 8 :qword)
  (defreg rbp 10 :qword)
  (defreg rsi 12 :qword)
  (defreg rdi 14 :qword)
  (defreg r8  16 :qword)
  (defreg r9  18 :qword)
  (defreg r10 20 :qword)
  (defreg r11 22 :qword)
  (defreg r12 24 :qword)
  (defreg r13 26 :qword)
  (defreg r14 28 :qword)
  (defreg r15 30 :qword)
  ;; for no good reason at the time, r12 and r13 were missed from the
  ;; list of qword registers.  However
  ;; <jsnell> r13 is already used as temporary [#lisp irc 2005/01/30]
  ;; and we're now going to use r12 for the struct thread*
  ;;
  ;; Except that now we use r11 instead of r13 as the temporary,
  ;; since it's got a more compact encoding than r13, and experimentally
  ;; the temporary gets used more than the other registers that are never
  ;; wired. -- JES, 2005-11-02
  (defregset *qword-regs* rax rcx rdx rbx rsi rdi
             r8 r9 r10 #+nil r11 #+nil r12 r13  r14 r15)

  ;; floating point registers
  (defreg float0 0 :float)
  (defreg float1 1 :float)
  (defreg float2 2 :float)
  (defreg float3 3 :float)
  (defreg float4 4 :float)
  (defreg float5 5 :float)
  (defreg float6 6 :float)
  (defreg float7 7 :float)
  (defreg float8 8 :float)
  (defreg float9 9 :float)
  (defreg float10 10 :float)
  (defreg float11 11 :float)
  (defreg float12 12 :float)
  (defreg float13 13 :float)
  (defreg float14 14 :float)
  (defreg float15 15 :float)
  (defregset *float-regs* float0 float1 float2 float3 float4 float5 float6 float7
             float8 float9 float10 float11 float12 float13 float14 float15)

  ;; registers used to pass arguments
  ;;
  ;; the number of arguments/return values passed in registers
  (def!constant  register-arg-count 3)
  ;; names and offsets for registers used to pass arguments
  (eval-when (:compile-toplevel :load-toplevel :execute)
    (defparameter *register-arg-names* '(rdx rdi rsi)))
  (defregset    *register-arg-offsets* rdx rdi rsi)
  (defregset    *c-call-register-arg-offsets* rdi rsi rdx rcx r8 r9))

;;;; SB definitions

;;; There are 16 registers really, but we consider them 32 in order to
;;; describe the overlap of byte registers. The only thing we need to
;;; represent is what registers overlap. Therefore, we consider bytes
;;; to take one unit, and [dq]?words to take two. We don't need to
;;; tell the difference between [dq]?words, because you can't put two
;;; words in a dword register.
(define-storage-base registers :finite :size 32)

(define-storage-base float-registers :finite :size 16)

(define-storage-base stack :unbounded :size 8)
(define-storage-base constant :non-packed)
(define-storage-base immediate-constant :non-packed)
(define-storage-base noise :unbounded :size 2)

;;;; SC definitions

;;; a handy macro so we don't have to keep changing all the numbers whenever
;;; we insert a new storage class
;;;
(defmacro !define-storage-classes (&rest classes)
  (collect ((forms))
    (let ((index 0))
      (dolist (class classes)
        (let* ((sc-name (car class))
               (constant-name (symbolicate sc-name "-SC-NUMBER")))
          (forms `(define-storage-class ,sc-name ,index
                    ,@(cdr class)))
          (forms `(def!constant ,constant-name ,index))
          (incf index))))
    `(progn
       ,@(forms))))

;;; The DEFINE-STORAGE-CLASS call for CATCH-BLOCK refers to the size
;;; of CATCH-BLOCK. The size of CATCH-BLOCK isn't calculated until
;;; later in the build process, and the calculation is entangled with
;;; code which has lots of predependencies, including dependencies on
;;; the prior call of DEFINE-STORAGE-CLASS. The proper way to
;;; unscramble this would be to untangle the code, so that the code
;;; which calculates the size of CATCH-BLOCK can be separated from the
;;; other lots-of-dependencies code, so that the code which calculates
;;; the size of CATCH-BLOCK can be executed early, so that this value
;;; is known properly at this point in compilation. However, that
;;; would be a lot of editing of code that I (WHN 19990131) can't test
;;; until the project is complete. So instead, I set the correct value
;;; by hand here (a sort of nondeterministic guess of the right
;;; answer:-) and add an assertion later, after the value is
;;; calculated, that the original guess was correct.
;;;
;;; (What a KLUDGE! Anyone who wants to come in and clean up this mess
;;; has my gratitude.) (FIXME: Maybe this should be me..)
(eval-when (:compile-toplevel :load-toplevel :execute)
  (def!constant kludge-nondeterministic-catch-block-size 6))

(!define-storage-classes

  ;; non-immediate constants in the constant pool
  (constant constant)

  (fp-single-zero immediate-constant)
  (fp-double-zero immediate-constant)

  (immediate immediate-constant)

  ;;
  ;; the stacks
  ;;

  ;; the control stack
  (control-stack stack)                 ; may be pointers, scanned by GC

  ;; the non-descriptor stacks
  ;; XXX alpha backend has :element-size 2 :alignment 2 in these entries
  (signed-stack stack)                  ; (signed-byte 64)
  (unsigned-stack stack)                ; (unsigned-byte 64)
  (character-stack stack)               ; non-descriptor characters.
  (sap-stack stack)                     ; System area pointers.
  (single-stack stack)                  ; single-floats
  (double-stack stack)
  (complex-single-stack stack :element-size 2)  ; complex-single-floats
  (complex-double-stack stack :element-size 2)  ; complex-double-floats


  ;;
  ;; magic SCs
  ;;

  (ignore-me noise)

  ;;
  ;; things that can go in the integer registers
  ;;

  ;; On the X86, we don't have to distinguish between descriptor and