From: Guillermo J. Rozas <edu/mit/csail/zurich/gjr>
Date: Wed, 5 Aug 1992 22:13:59 +0000 (+0000)
Subject: Fix swapped opcodes bug in i486 manual (FDIV <-> FDIVR, FSUB <->
X-Git-Tag: 20090517-FFI~9159
X-Git-Url: https://birchwood-abbey.net/git?a=commitdiff_plain;h=97ce458bc7b4e43fc1f92c60be8fd16972b3afde;p=mit-scheme.git

Fix swapped opcodes bug in i486 manual (FDIV <-> FDIVR, FSUB <->
FSUBR).
---

diff --git a/v7/src/compiler/machines/i386/instrf.scm b/v7/src/compiler/machines/i386/instrf.scm
index 02a4d1008..656fde53a 100644
--- 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 1.10 1992/02/28 20:22:42 jinx Exp $
+$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 $
 
 Copyright (c) 1992 Massachusetts Institute of Technology
 
@@ -57,9 +57,15 @@ MIT in each case. |#
 	       (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))))
+		     ;; (8 (+ ,opcode2 i))
+		     (8 (+ ,opcode1 i))
+		     ))
 
 	      (()
 	       (BYTE (8 #xde)