tests/foreign-stack-alignment.impure.lisp

   1 ;;;; Testing the stack alignment of foreign calls. Uses stack-alignment-offset.c.
   2
   3 ;;;; This software is part of the SBCL system. See the README file for
   4 ;;;; more information.
   5 ;;;;
   6 ;;;; While most of SBCL is derived from the CMU CL system, the test
   7 ;;;; files (like this one) were written from scratch after the fork
   8 ;;;; from CMU CL.
   9 ;;;;
  10 ;;;; This software is in the public domain and is provided with
  11 ;;;; absolutely no warranty. See the COPYING and CREDITS files for
  12 ;;;; more information.
  13
  14 (use-package :sb-alien)
  15
  16 ;;; Callbacks are not part of the exported interface yet -- when they are this can
  17 ;;; go away.
  18 (import 'sb-alien::alien-lambda)
  19
  20 (defun run (program &rest arguments)
  21   (let* ((proc nil)
  22          (output
  23           (with-output-to-string (s)
  24             (setf proc (run-program program arguments
  25                                     :search (not (eql #\. (char program 0)))
  26                                     :output s)))))
  27     (unless (zerop (process-exit-code proc))
  28       (error "Bad exit code: ~S~%Output:~% ~S"
  29              (process-exit-code proc)
  30              output))
  31     output))
  32
  33 (defvar *required-alignment*
  34   #+(and ppc darwin) 16
  35   #+(and ppc linux) 8
  36   #+x86-64 16
  37   #+mips 8
  38   #+x86 4
  39   #-(or x86 x86-64 mips (and ppc (or darwin linux))) (error "Unknown platform"))
  40
  41 ;;;; Build the offset-tool as regular excutable, and run it with
  42 ;;;; fork/exec, so that no lisp is on the stack. This is our known-good
  43 ;;;; number.
  44
  45 (run "cc"
  46      #+(and (or linux freebsd) (or x86-64 ppc)) "-fPIC"
  47      "stack-alignment-offset.c" "-o" "stack-alignment-offset")
  48
  49 (defparameter *good-offset*
  50   (parse-integer (run "./stack-alignment-offset"
  51                       (princ-to-string *required-alignment*))))
  52
  53 ;;;; Build the tool again, this time as a shared object, and load it
  54
  55 (run "cc" "stack-alignment-offset.c"
  56      #+(and (or linux freebsd) (or x86-64 ppc)) "-fPIC"
  57      #+darwin "-bundle" #-darwin "-shared"
  58      "-o" "stack-alignment-offset.so")
  59
  60 (load-shared-object "stack-alignment-offset.so")
  61
  62 (define-alien-routine stack-alignment-offset int (alignment int))
  63 (define-alien-routine trampoline int (callback (function int)))
  64
  65 ;;;; Now get the offset by calling from lisp, first with a regular foreign function
  66 ;;;; call, then with an intervening callback.
  67
  68 (with-test (:name :regular)
  69   (assert (= *good-offset* (stack-alignment-offset *required-alignment*))))
  70
  71 (with-test (:name :callback)
  72   (assert (= *good-offset* (trampoline (alien-lambda int ()
  73                                        (stack-alignment-offset *required-alignment*))))))
  74
  75 ;;;; success!