src/code/ppc-vm.lisp

   1 ;;; This file contains the PPC specific runtime stuff.
   2 ;;;
   3 (in-package "SB-VM")
   4
   5 (defun machine-type ()
   6   "Returns a string describing the type of the local machine."
   7   #-64-bit "PowerPC"
   8   #+64-bit "PowerPC64")
   9
  10 (defun return-machine-address (scp)
  11   (sap-int (context-lr scp)))
  12
  13 \f
  14
  15 ;;;; "Sigcontext" access functions, cut & pasted from x86-vm.lisp then
  16 ;;;; hacked for types.
  17
  18 (define-alien-routine ("os_context_lr_addr" context-lr-addr) (* unsigned-long)
  19   (context (* os-context-t)))
  20
  21 (defun context-lr (context)
  22   (declare (type (alien (* os-context-t)) context))
  23   (int-sap (deref (context-lr-addr context))))
  24 ;;; This is like CONTEXT-REGISTER, but returns the value of a float
  25 ;;; register. FORMAT is the type of float to return.
  26
  27 ;;; FIXME: Whether COERCE actually knows how to make a float out of a
  28 ;;; long is another question. This stuff still needs testing.
  29 #+nil
  30 (define-alien-routine ("os_context_fpregister_addr" context-float-register-addr)
  31   (* long)
  32   (context (* os-context-t))
  33   (index int))
  34 (defun context-float-register (context index format)
  35   (declare (type (alien (* os-context-t)) context))
  36   (error "context-float-register not working yet? ~S" (list context index format))
  37   #+nil
  38   (coerce (deref (context-float-register-addr context index)) format))
  39 (defun %set-context-float-register (context index format new)
  40   (declare (type (alien (* os-context-t)) context))
  41   (error "%set-context-float-register not working yet? ~S" (list context index format new))
  42   #+nil
  43   (setf (deref (context-float-register-addr context index))
  44         (coerce new format)))
  45
  46 ;;; Given a signal context, return the floating point modes word in
  47 ;;; the same format as returned by FLOATING-POINT-MODES.
  48 ;;;
  49 ;;; FIXME: surely this must be accessible under some other operating systems?
  50 #+linux
  51 (define-alien-routine ("os_context_fp_control" context-floating-point-modes)
  52     (unsigned 32)
  53   (context (* os-context-t)))
  54
  55 \f
  56 ;;;; INTERNAL-ERROR-ARGS.
  57
  58 ;;; GIVEN a (POSIX) signal context, extract the internal error
  59 ;;; arguments from the instruction stream.  This is e.g.
  60
  61 ;;; INTERNAL-ERROR-ARGS -- interface.
  62 ;;;
  63 ;;; Given the sigcontext, extract the internal error arguments from the
  64 ;;; instruction stream.
  65 ;;;
  66 (defun internal-error-args (context)
  67   (declare (type (alien (* os-context-t)) context))
  68   (let* ((pc (context-pc context))
  69          (bad-inst (sap-ref-32 pc 0))
  70          (op (ldb (byte 16 16) bad-inst))
  71          (regnum (ldb (byte 5 0) op)))
  72     (declare (type system-area-pointer pc))
  73     (cond ((= op #+64-bit
  74                  (logior (ash 2 10) (ash 1 5) null-offset) ;; TDI LGT,$NULL
  75                  #-64-bit
  76                  (logior (ash 3 10) (ash 6 5))) ;; twllei r0
  77            (let ((trap-number (ldb (byte 8 0) bad-inst)))
  78              (sb-kernel::decode-internal-error-args (sap+ pc 4) trap-number)))
  79           ((and (= (ldb (byte 6 10) op) 3) ;; twi
  80                 (or (= regnum #.(sc+offset-offset arg-count-sc))
  81                     (= (ldb (byte 5 5) op) 24))) ;; :ne
  82            ;; Type errors are encoded as
  83            ;; twi 0 value-register error-code
  84            ;; twi :ne temp-register x
  85            (let ((prev (sap-ref-32 (int-sap (- (sap-int pc) 4)) 0)))
  86              (if (and (= (ldb (byte 5 5) op) 24) ;; is the condition :ne?
  87                       (= (ldb (byte 6 26) prev) 3) ;; is it twi?
  88                       (= (ldb (byte 5 21) prev) 0)) ;; is it non-trapping?
  89                  (values (ldb (byte 16 0) prev)
  90                          (list (make-sc+offset any-reg-sc-number
  91                                                (ldb (byte 5 16) prev))))
  92                  ;; arg-count errors are encoded as
  93                  ;; twi {:ne :llt :lgt} nargs arg-count
  94                  (values #.(error-number-or-lose 'invalid-arg-count-error)
  95                          '(#.arg-count-sc)))))
  96           (t
  97            (values #.(error-number-or-lose 'unknown-error) nil)))))
  98
  99 ;;; To support linkage-space as efficiently as on x86-64, these
 100 ;;; things have to happen:
 101 ;;; * funcallable-instances must become directly callable objects
 102 ;;; * simple-fun-self, closure-fun, fin-fun must be raw addresses
 103 ;;; * LRAs should be removed
 104 ;;; For now, I'm using a hand-assembled simple-fun as simplifying wrapper
 105 ;;; since executable funinstances are not supported.
 106 #+64-bit
 107 (progn
 108 (defun ensure-simplistic (function name)
 109   (when (simple-fun-p function)
 110     (return-from ensure-simplistic function))
 111   (binding*
 112       ((nraw (* 8 n-word-bytes))
 113        (code (sb-c:allocate-code-object nil 4 nraw))
 114        ;; FIXME: why does an undef FUNCTION come in as either/or? Can I settle on just one?
 115        (undef (or (eql function 0) (null function)))
 116        ;; It's nice if these blobs of code are all the same size but the funinstance case
 117        ;; doesn't fit entirely within NRAW bytes, so it calls an ASM routine.
 118        ((insts helper)
 119         (cond (undef
 120                (values
 121                 #(#xE95FFFD8     ; LD $FDEFN,-40($LIP)     ; [debug-info] = the function name
 122                   #x3BF20000     ; ADDI $LIP,$NULL,x       ; UNDEFINED-TRAMP
 123                   #x7FE903A6     ; MTCTR $LIP
 124                   #x4E800420)    ; BCTR
 125                 'undefined-tramp))
 126               ((funcallable-instance-p function)
 127                (values
 128                 #(#xEABFFFD8     ; LD $LEXENV,-40($LIP)    ; [debug-info] = the funinstance
 129                   #x3BF20000     ; ADDI $LIP,$NULL,x       ; FUNCALLABLE-INSTANCE-TRAMP
 130                   #x7FE903A6     ; MTCTR $LIP
 131                   #x4E800420)    ; BCTR
 132                 'funcallable-instance-tramp))
 133               (t ; closure
 134                #(#xEABFFFD8      ; LD $LEXENV,-40($LIP)    ; [debug-info] = the closure
 135                  #x38000002      ; ADDI $ZERO,$ZERO,2
 136                  #x7FF5002A      ; LDX $LIP,$LEXENV,$ZERO  ; get closure's simple-fun entrypoint
 137                  #x7FE903A6      ; MTCTR $LIP
 138                  #x4E800420))))) ; BCTR
 139     (with-pinned-objects (code)
 140       (let ((self (sap+ (code-instructions code) 16)))
 141         (setf (sap-ref-word self (ash -2 word-shift)) 1 ; jump table word count
 142               (sap-ref-word self (ash -1 word-shift)) 0 ; unused
 143               (sap-ref-word self 0) (logior #x600 simple-fun-widetag)
 144               (sap-ref-sap self 8) (sap+ self 16))
 145         (let ((start (sap+ self 16)))
 146           (dotimes (i (length insts))
 147             (setf (sap-ref-32 start (ash i 2)) (aref insts i)))
 148           (when helper
 149             (let ((imm (- (sb-fasl:get-asm-routine helper) nil-value)))
 150               (setf (sap-ref-32 start 4) (logior (sap-ref-32 start 4) imm)))))
 151         ;; Store trailing data
 152         (let ((end (sap+ self (- nraw 16)))) ; undo 16 added above
 153           (setf (sap-ref-32 end -8) #x10 ; code-instructions to fun-base offset
 154                 (sap-ref-16 end -4) (ash 1 5) ; simple-fun count
 155                 (sap-ref-16 end -2) 8)))) ; trailer len in bytes
 156     (code-header-set code code-debug-info-slot (if undef name function))
 157     (%code-entry-point code 0)))
 158
 159 (defun stepper-fun (closure) (ensure-simplistic closure nil))
 160 ) ; end PROGN