Fix more floating-point documentation bugs.

diff --git a/v7/src/compiler/machines/i386/instrf.scm b/v7/src/compiler/machines/i386/instrf.scm
index 656fde53a9cc7f7be88fca5d5755e7bf8755bb8c..5d1cadf7459f6447bec54187ebdef719cd002e23 100644 (file)
--- a/v7/src/compiler/machines/i386/instrf.scm
+++ b/v7/src/compiler/machines/i386/instrf.scm
@@ -1,6 +1,6 @@
 #| -*-Scheme-*-
 
-$Header: /Users/cph/tmp/foo/mit-scheme/mit-scheme/v7/src/compiler/machines/i386/instrf.scm,v 1.11 1992/08/05 22:13:59 jinx Exp $
+$Header: /Users/cph/tmp/foo/mit-scheme/mit-scheme/v7/src/compiler/machines/i386/instrf.scm,v 1.12 1992/08/05 23:34:40 jinx Exp $
 
 Copyright (c) 1992 Massachusetts Institute of Technology
 
@@ -51,16 +51,18 @@ MIT in each case. |#
 (let-syntax
     ((define-binary-flonum
        (macro (mnemonic pmnemonic imnemonic digit opcode1 opcode2)
+        ;; In the following code, the commented code follows the i486
+        ;; manual, which is wrong.  The uncommented versions agree
+        ;; with the hardware and the description in the i486 book.
+
+        opcode2                        ; ignored
+
         `(begin
            (define-instruction ,mnemonic
              (((ST 0) (ST (? i)))
               (BYTE (8 #xd8)
                     (8 (+ ,opcode1 i))))
 
-             ;; In the following case, the manual uses opcode2
-             ;; but the instructions (FDIV <-> FDIVR, FSUB <-> FSUBR)
-             ;; are actually backwards.
-
              (((ST (? i)) (ST 0))
               (BYTE (8 #xdc)
                     ;; (8 (+ ,opcode2 i))
@@ -69,7 +71,9 @@ MIT in each case. |#
 
              (()
               (BYTE (8 #xde)
-                    (8 (+ ,opcode2 1))))
+                    ;; (8 (+ ,opcode2 1))
+                    (8 (+ ,opcode1 1))
+                    ))
 
              ((D (? source mW))
               (BYTE (8 #xdc))
@@ -82,7 +86,9 @@ MIT in each case. |#
            (define-instruction ,pmnemonic
              (((ST (? i)) (ST 0))
               (BYTE (8 #xde)
-                    (8 (+ ,opcode2 i)))))
+                    ;; (8 (+ ,opcode2 i))
+                    (8 (+ ,opcode1 i))
+                    )))
 
            (define-instruction ,imnemonic
              ((L (? source mW))