Audit use of lsh and fix glitches

I audited use of lsh in the Lisp source code, and fixed the
glitches that I found.  While I was at it, I replaced uses of lsh
with ash when either will do.  Replacement is OK when either
argument is known to be nonnegative, or when only the low-order
bits of the result matter, and is a (minor) win since ash is a bit
more solid than lsh nowadays, and is a bit faster.
* lisp/calc/calc-ext.el (math-check-fixnum):
Prefer most-positive-fixnum to (lsh -1 -1).
* lisp/vc/vc-hg.el (vc-hg-state-fast): When testing fixnum width,
prefer (zerop (ash most-positive-fixnum -32)) to (zerop (lsh -1
32)) (Bug#32485#11).
* lisp/emacs-lisp/bytecomp.el (byte-compile-lapcode):
Tighten sanity-check for bytecode overflow, by checking that the
result of (ash pc -8) is nonnegative.  Formerly this check was not
needed since lsh was used and the number overflowed differently.
* lisp/net/dns.el (dns-write): Fix some obvious sign typos in
shift counts.  Evidently this part of the code has never been
exercised.
* lisp/progmodes/hideif.el (hif-shiftleft, hif-shiftright):
* lisp/term/common-win.el (x-setup-function-keys):
Simplify.
* admin/unidata/unidata-gen.el, admin/unidata/uvs.el:
* doc/lispref/keymaps.texi, doc/lispref/syntax.texi:
* doc/misc/calc.texi, doc/misc/cl.texi, etc/NEWS.19:
* lisp/arc-mode.el, lisp/calc/calc-bin.el, lisp/calc/calc-comb.el:
* lisp/calc/calc-ext.el, lisp/calc/calc-math.el:
* lisp/cedet/semantic/wisent/comp.el, lisp/composite.el:
* lisp/disp-table.el, lisp/dos-fns.el, lisp/edmacro.el:
* lisp/emacs-lisp/bindat.el, lisp/emacs-lisp/byte-opt.el:
* lisp/emacs-lisp/bytecomp.el, lisp/emacs-lisp/cl-extra.el:
* lisp/erc/erc-dcc.el, lisp/facemenu.el, lisp/gnus/message.el:
* lisp/gnus/nndoc.el, lisp/gnus/nnmaildir.el, lisp/image.el:
* lisp/international/ccl.el, lisp/international/fontset.el:
* lisp/international/mule-cmds.el, lisp/international/mule.el:
* lisp/json.el, lisp/mail/binhex.el, lisp/mail/rmail.el:
* lisp/mail/uudecode.el, lisp/md4.el, lisp/net/dns.el:
* lisp/net/ntlm.el, lisp/net/sasl.el, lisp/net/socks.el:
* lisp/net/tramp.el, lisp/obsolete/levents.el:
* lisp/obsolete/pgg-parse.el, lisp/org/org.el:
* lisp/org/ox-publish.el, lisp/progmodes/cc-defs.el:
* lisp/progmodes/ebnf2ps.el, lisp/progmodes/hideif.el:
* lisp/ps-bdf.el, lisp/ps-print.el, lisp/simple.el:
* lisp/tar-mode.el, lisp/term/common-win.el:
* lisp/term/tty-colors.el, lisp/term/xterm.el, lisp/vc/vc-git.el:
* lisp/vc/vc-hg.el, lisp/x-dnd.el, test/src/data-tests.el:
Prefer ash to lsh when either will do.

4 files changed, 23 insertions, 23 deletions

diff --git a/lisp/emacs-lisp/bindat.el b/lisp/emacs-lisp/bindat.el
index c1343765901..3124217303f 100644
--- a/lisp/emacs-lisp/bindat.el
+++ b/lisp/emacs-lisp/bindat.el
@@ -205,22 +205,22 @@
     (setq bindat-idx (1+ bindat-idx))))
 
 (defun bindat--unpack-u16 ()
-  (logior (lsh (bindat--unpack-u8) 8) (bindat--unpack-u8)))
+  (logior (ash (bindat--unpack-u8) 8) (bindat--unpack-u8)))
 
 (defun bindat--unpack-u24 ()
-  (logior (lsh (bindat--unpack-u16) 8) (bindat--unpack-u8)))
+  (logior (ash (bindat--unpack-u16) 8) (bindat--unpack-u8)))
 
 (defun bindat--unpack-u32 ()
-  (logior (lsh (bindat--unpack-u16) 16) (bindat--unpack-u16)))
+  (logior (ash (bindat--unpack-u16) 16) (bindat--unpack-u16)))
 
 (defun bindat--unpack-u16r ()
-  (logior (bindat--unpack-u8) (lsh (bindat--unpack-u8) 8)))
+  (logior (bindat--unpack-u8) (ash (bindat--unpack-u8) 8)))
 
 (defun bindat--unpack-u24r ()
-  (logior (bindat--unpack-u16r) (lsh (bindat--unpack-u8) 16)))
+  (logior (bindat--unpack-u16r) (ash (bindat--unpack-u8) 16)))
 
 (defun bindat--unpack-u32r ()
-  (logior (bindat--unpack-u16r) (lsh (bindat--unpack-u16r) 16)))
+  (logior (bindat--unpack-u16r) (ash (bindat--unpack-u16r) 16)))
 
 (defun bindat--unpack-item (type len &optional vectype)
   (if (eq type 'ip)
@@ -250,7 +250,7 @@
 	    (if (/= 0 (logand m j))
 		(setq bits (cons bnum bits)))
 	    (setq bnum (1- bnum)
-		  j (lsh j -1)))))
+		  j (ash j -1)))))
       bits))
    ((eq type 'str)
     (let ((s (substring bindat-raw bindat-idx (+ bindat-idx len))))
@@ -459,30 +459,30 @@ e.g. corresponding to STRUCT.FIELD1[INDEX2].FIELD3..."
   (setq bindat-idx (1+ bindat-idx)))
 
 (defun bindat--pack-u16 (v)
-  (aset bindat-raw bindat-idx (logand (lsh v -8) 255))
+  (aset bindat-raw bindat-idx (logand (ash v -8) 255))
   (aset bindat-raw (1+ bindat-idx) (logand v 255))
   (setq bindat-idx (+ bindat-idx 2)))
 
 (defun bindat--pack-u24 (v)
-  (bindat--pack-u8 (lsh v -16))
+  (bindat--pack-u8 (ash v -16))
   (bindat--pack-u16 v))
 
 (defun bindat--pack-u32 (v)
-  (bindat--pack-u16 (lsh v -16))
+  (bindat--pack-u16 (ash v -16))
   (bindat--pack-u16 v))
 
 (defun bindat--pack-u16r (v)
-  (aset bindat-raw (1+ bindat-idx) (logand (lsh v -8) 255))
+  (aset bindat-raw (1+ bindat-idx) (logand (ash v -8) 255))
   (aset bindat-raw bindat-idx (logand v 255))
   (setq bindat-idx (+ bindat-idx 2)))
 
 (defun bindat--pack-u24r (v)
   (bindat--pack-u16r v)
-  (bindat--pack-u8 (lsh v -16)))
+  (bindat--pack-u8 (ash v -16)))
 
 (defun bindat--pack-u32r (v)
   (bindat--pack-u16r v)
-  (bindat--pack-u16r (lsh v -16)))
+  (bindat--pack-u16r (ash v -16)))
 
 (defun bindat--pack-item (v type len &optional vectype)
   (if (eq type 'ip)
@@ -515,7 +515,7 @@ e.g. corresponding to STRUCT.FIELD1[INDEX2].FIELD3..."
 	    (if (memq bnum v)
 		(setq m (logior m j)))
 	    (setq bnum (1- bnum)
-		  j (lsh j -1))))
+		  j (ash j -1))))
 	(bindat--pack-u8 m))))
    ((memq type '(str strz))
     (let ((l (length v)) (i 0))
diff --git a/lisp/emacs-lisp/byte-opt.el b/lisp/emacs-lisp/byte-opt.el
index 1920503b8c4..4854808fd02 100644
--- a/lisp/emacs-lisp/byte-opt.el
+++ b/lisp/emacs-lisp/byte-opt.el
@@ -1283,7 +1283,7 @@
 		  (setq bytedecomp-ptr (1+ bytedecomp-ptr))
 		  (+ (aref bytes bytedecomp-ptr)
 		     (progn (setq bytedecomp-ptr (1+ bytedecomp-ptr))
-			    (lsh (aref bytes bytedecomp-ptr) 8))))
+			    (ash (aref bytes bytedecomp-ptr) 8))))
 		 (t tem))))		;Offset was in opcode.
 	((>= bytedecomp-op byte-constant)
 	 (prog1 (- bytedecomp-op byte-constant)	;Offset in opcode.
@@ -1297,7 +1297,7 @@
 	 (setq bytedecomp-ptr (1+ bytedecomp-ptr))
 	 (+ (aref bytes bytedecomp-ptr)
 	    (progn (setq bytedecomp-ptr (1+ bytedecomp-ptr))
-		   (lsh (aref bytes bytedecomp-ptr) 8))))
+		   (ash (aref bytes bytedecomp-ptr) 8))))
 	((and (>= bytedecomp-op byte-listN)
 	      (<= bytedecomp-op byte-discardN))
 	 (setq bytedecomp-ptr (1+ bytedecomp-ptr)) ;Offset in next byte.
diff --git a/lisp/emacs-lisp/bytecomp.el b/lisp/emacs-lisp/bytecomp.el
index ee28e61800d..0b8f8824b4c 100644
--- a/lisp/emacs-lisp/bytecomp.el
+++ b/lisp/emacs-lisp/bytecomp.el
@@ -835,7 +835,7 @@ all the arguments.
 (defmacro byte-compile-push-bytecode-const2 (opcode const2 bytes pc)
   "Push OPCODE and the two-byte constant CONST2 onto BYTES, and add 3 to PC.
 CONST2 may be evaluated multiple times."
-  `(byte-compile-push-bytecodes ,opcode (logand ,const2 255) (lsh ,const2 -8)
+  `(byte-compile-push-bytecodes ,opcode (logand ,const2 255) (ash ,const2 -8)
 				,bytes ,pc))
 
 (defun byte-compile-lapcode (lap)
@@ -925,9 +925,9 @@ CONST2 may be evaluated multiple times."
       ;; Splits PC's value into 2 bytes. The jump address is
       ;; "reconstructed" by the `FETCH2' macro in `bytecode.c'.
       (setcar (cdr bytes-tail) (logand pc 255))
-      (setcar bytes-tail (lsh pc -8))
+      (setcar bytes-tail (ash pc -8))
       ;; FIXME: Replace this by some workaround.
-      (if (> (car bytes-tail) 255) (error "Bytecode overflow")))
+      (or (<= 0 (car bytes-tail) 255) (error "Bytecode overflow")))
 
     ;; Similarly, replace TAGs in all jump tables with the correct PC index.
     (dolist (hash-table byte-compile-jump-tables)
@@ -2793,8 +2793,8 @@ If FORM is a lambda or a macro, byte-compile it as a function."
     (if (> mandatory 127)
         (byte-compile-report-error "Too many (>127) mandatory arguments")
       (logior mandatory
-              (lsh nonrest 8)
-              (lsh rest 7)))))
+              (ash nonrest 8)
+              (ash rest 7)))))
 
 
 (defun byte-compile-lambda (fun &optional add-lambda reserved-csts)
@@ -3258,7 +3258,7 @@ for symbols generated by the byte compiler itself."
          (fun (car form))
          (fargs (aref fun 0))
          (start-depth byte-compile-depth)
-         (fmax2 (if (numberp fargs) (lsh fargs -7)))     ;2*max+rest.
+         (fmax2 (if (numberp fargs) (ash fargs -7)))     ;2*max+rest.
          ;; (fmin (if (numberp fargs) (logand fargs 127)))
          (alen (length (cdr form)))
          (dynbinds ())
diff --git a/lisp/emacs-lisp/cl-extra.el b/lisp/emacs-lisp/cl-extra.el
index 36b65f97b07..bea38a05096 100644
--- a/lisp/emacs-lisp/cl-extra.el
+++ b/lisp/emacs-lisp/cl-extra.el
@@ -472,7 +472,7 @@ Optional second arg STATE is a random-state object."
 	   (n (logand 8388607 (aset vec i (- (aref vec i) (aref vec j))))))
       (if (integerp lim)
 	  (if (<= lim 512) (% n lim)
-	    (if (> lim 8388607) (setq n (+ (lsh n 9) (cl-random 512 state))))
+	    (if (> lim 8388607) (setq n (+ (ash n 9) (cl-random 512 state))))
 	    (let ((mask 1023))
 	      (while (< mask (1- lim)) (setq mask (1+ (+ mask mask))))
 	      (if (< (setq n (logand n mask)) lim) n (cl-random lim state))))