X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fcode%2Fearly-extensions.lisp;h=a3c401c8c42bb2b58b78cecca0f51b82d63c5020;hb=a74b0bdb483504f6faddf8089f848f61ed94b92a;hp=0f6fba90991fef888cf77c3941955962c7de0b28;hpb=8731c1a7c1a585d190151fa881050fb5e14c0616;p=sbcl.git

diff --git a/src/code/early-extensions.lisp b/src/code/early-extensions.lisp
index 0f6fba9..a3c401c 100644
--- a/src/code/early-extensions.lisp
+++ b/src/code/early-extensions.lisp
@@ -36,6 +36,35 @@
 ;;; index leaving the loop range)
 (def!type index-or-minus-1 () `(integer -1 (,sb!xc:array-dimension-limit)))
 
+;;; A couple of VM-related types that are currently used only on the
+;;; alpha platform. -- CSR, 2002-06-24
+(def!type unsigned-byte-with-a-bite-out (s bite)
+  (cond ((eq s '*) 'integer)
+        ((and (integerp s) (> s 0))
+         (let ((bound (ash 1 s)))
+           `(integer 0 ,(- bound bite 1))))
+        (t
+         (error "Bad size specified for UNSIGNED-BYTE type specifier: ~S." s))))
+
+;;; Motivated by the mips port. -- CSR, 2002-08-22
+(def!type signed-byte-with-a-bite-out (s bite)
+  (cond ((eq s '*) 'integer)
+	((and (integerp s) (> s 1))
+	 (let ((bound (ash 1 (1- s))))
+	   `(integer ,(- bound) ,(- bound bite 1))))
+	(t
+	 (error "Bad size specified for SIGNED-BYTE type specifier: ~S." s))))
+
+(def!type load/store-index (scale lowtag min-offset
+				 &optional (max-offset min-offset))
+  `(integer ,(- (truncate (+ (ash 1 16)
+			     (* min-offset sb!vm:n-word-bytes)
+			     (- lowtag))
+			  scale))
+	    ,(truncate (- (+ (1- (ash 1 16)) lowtag)
+			  (* max-offset sb!vm:n-word-bytes))
+		       scale)))
+
 ;;; the default value used for initializing character data. The ANSI
 ;;; spec says this is arbitrary, so we use the value that falls
 ;;; through when we just let the low-level consing code initialize
@@ -531,6 +560,19 @@
 			     ,@(values-names))
 			    (values ,@(values-names)))
 			  (values ,@(values-names))))))))))))
+
+(defmacro define-cached-synonym
+    (name &optional (original (symbolicate "%" name)))
+  (let ((cached-name (symbolicate "%%" name "-cached")))
+    `(progn
+       (defun-cached (,cached-name :hash-bits 8
+                                   :hash-function (lambda (x)
+                                                    (logand (sxhash x) #xff)))
+           ((args equal))
+         (apply #',original args))
+       (defun ,name (&rest args)
+         (,cached-name args)))))
+
 
 ;;;; package idioms
 
@@ -568,8 +610,23 @@
            (symbolp (cadr name))
            (null (cddr name)))))
 
-;;; Given a function name, return the name for the BLOCK which
-;;; encloses its body (e.g. in DEFUN, DEFINE-COMPILER-MACRO, or FLET).
+;;; Signal an error unless NAME is a legal function name.
+(defun legal-fun-name-or-type-error (name)
+  (unless (legal-fun-name-p name)
+    (error 'simple-type-error
+	   :datum name
+	   :expected-type '(or symbol list)
+	   :format-control "invalid function name: ~S"
+	   :format-arguments (list name))))
+
+;;; Given a function name, return the symbol embedded in it.
+;;;
+;;; The ordinary use for this operator (and the motivation for the
+;;; name of this operator) is to convert from a function name to the
+;;; name of the BLOCK which encloses its body.
+;;;
+;;; Occasionally the operator is useful elsewhere, where the operator
+;;; name is less mnemonic. (Maybe it should be changed?)
 (declaim (ftype (function ((or symbol cons)) symbol) fun-name-block-name))
 (defun fun-name-block-name (fun-name)
   (cond ((symbolp fun-name)
@@ -977,3 +1034,17 @@ which can be found at <http://sbcl.sourceforge.net/>.~:@>"
   (warn "using deprecated ~S~@[, should use ~S instead~]"
 	bad-name
 	good-name))
+
+;;; Anaphoric macros
+(defmacro awhen (test &body body)
+  `(let ((it ,test))
+     (when it ,@body)))
+
+(defmacro acond (&rest clauses)
+  (if (null clauses)
+      `()
+      (destructuring-bind ((test &body body) &rest rest) clauses
+        (once-only ((test test))
+          `(if ,test
+               (let ((it ,test)) (declare (ignorable it)),@body)
+               (acond ,@rest))))))