Re-enable PREFTECH, fix IP limit checking, and restore support for autoMount overrides

devices/pc/machine/compaq/deskpro386/ega/2048kb/machine.xml

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <?xml-stylesheet type="text/xsl" href="/versions/pcjs/1.21.0/machine.xsl"?>
 <machine id="deskpro386" class="pc" border="1" pos="center" background="#FAEBD7">
-	<name pos="center">COMPAQ DeskPro 386, 2Mb RAM, COMPAQ EGA</name>
+	<name pos="center">COMPAQ DeskPro 386, 2Mb RAM, 128Kb EGA</name>
 	<computer id="deskpro386-ega-2048k" name="COMPAQ DeskPro 386" buswidth="32"/>
 	<cpu id="cpu386" model="80386" autostart="false"/>
 	<ram id="ramLow" addr="0x00000" test="false" size="0xa0000" comment="ROM BIOS memory test has been disabled"/>

devices/pc/machine/compaq/deskpro386/ega/4096kb/machine.xml

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <?xml-stylesheet type="text/xsl" href="/versions/pcjs/1.21.0/machine.xsl"?>
 <machine id="deskpro386" class="pc" border="1" pos="center" background="#FAEBD7">
-	<name pos="center">COMPAQ DeskPro 386, 4Mb RAM, COMPAQ EGA</name>
+	<name pos="center">COMPAQ DeskPro 386, 4Mb RAM, 128Kb EGA</name>
 	<computer id="deskpro386-ega-2048k" name="COMPAQ DeskPro 386" buswidth="32"/>
 	<cpu id="cpu386" model="80386" autostart="false"/>
 	<ram id="ramLow" addr="0x00000" test="false" size="0xa0000" comment="ROM BIOS memory test has been disabled"/>

modules/markout/lib/markout.js

@@ -332,7 +332,7 @@ MarkOut.aHTMLEntities = {
  *      'config' (eg, "machine.xml")
  *      'template' (eg, "machine.xsl")
  *      'uncompiled' (eg, true)
- *      'automount' (eg, {"A":{"name":"OS/2 FOOTBALL Boot Disk (v7.68.17)","path":"/disks/pc/os2/misc/football/debugger/FOOTBALL-7.68.17.json"}})
+ *      'autoMount' (eg, {"A":{"name":"OS/2 FOOTBALL Boot Disk (v7.68.17)","path":"/disks/pc/os2/misc/football/debugger/FOOTBALL-7.68.17.json"}})
  *      'parms'
  *
  * Non-reserved properties include:
@@ -356,7 +356,7 @@ MarkOut.aHTMLEntities = {
 MarkOut.aFMBooleanMachineProps = {
     'autopower': "autoPower"
 };
-MarkOut.aFMReservedMachineProps = ['id', 'name', 'type', 'debugger', 'config', 'template', 'uncompiled', 'automount', 'parms'];
+MarkOut.aFMReservedMachineProps = ['id', 'name', 'type', 'debugger', 'config', 'template', 'uncompiled', 'autoMount', 'parms'];
 
 /**
  * convertMD()
@@ -436,17 +436,18 @@ MarkOut.prototype.convertMD = function(sIndent)
                     }
                     for (var iOption = 0; iOption < aaOptions.length; iOption++) {
                         aOptions = aaOptions[iOption];
-                        var sSpace = aOptions[1], sName = aOptions[2], sValue = aOptions[3];
+                        var sSpace = aOptions[1], sName = aOptions[2].toLowerCase(), sValue = aOptions[3];
+                        if (sName == 'automount') sName = 'autoMount';  // for backward compatibility
                         if (!id && sName == 'id') {
                             id = sValue;
-                        } else if (sName == 'automount') {
+                        } else if (sName == 'autoMount') {
                             /*
-                             * I take a simplistic approach to parsing the object definition associated with "automount",
+                             * I take a simplistic approach to parsing the object definition associated with "autoMount",
                              * because I know it only consists of 1 or more drive letters, each of which may be followed
                              * by 1 or 2 additional properties (eg, "name" and "path").  If we need to support other JSON
                              * object definitions in the future, this will have to be generalized.
                              *
-                             * Here's an example of "automount" output:
+                             * Here's an example of "autoMount" output:
                              *
                              *      {"A":{"name":"OS/2 FOOTBALL Boot Disk (v7.68.17)","path":"/disks/pc/os2/misc/football/debugger/FOOTBALL-7.68.17.json"}}
                              *
@@ -477,7 +478,7 @@ MarkOut.prototype.convertMD = function(sIndent)
                         machine[sName] = sValue;
                     }
                     /*
-                     * Any "non-reserved" properties are now merged into the 'parms' property; 'automount'
+                     * Any "non-reserved" properties are now merged into the 'parms' property; 'autoMount'
                      * is treated as reserved only because it must be encoded as an object rather than a string.
                      */
                     machine['parms'] = '{';
@@ -490,7 +491,7 @@ MarkOut.prototype.convertMD = function(sIndent)
                             machine['parms'] += sProp + ':"' + machine[sProp] + '",';
                         }
                     }
-                    machine['parms'] += 'autoMount:' + machine['automount'] + '}';
+                    machine['parms'] += 'autoMount:' + machine['autoMount'] + '}';
                     if (id) this.aMachineDefs[id] = machine;
                 }
             }

modules/pcjs/lib/cpu.js

@@ -529,9 +529,15 @@ CPU.prototype.setFocus = function()
          * into view.  The CPU is not a visual component, so when the CPU wants to set focus, the primary intent
          * is to ensure that keyboard input is fielded properly.
          */
-        var x = window.scrollX, y = window.scrollY;
+        var x = 0, y = 0;
+        if (window) {
+            x = window.scrollX;
+            y = window.scrollY;
+        }
         this.aVideo[0].setFocus();
-        window.scrollTo(x, y);
+        if (window) {
+            window.scrollTo(x, y);
+        }
     }
 };
 

modules/pcjs/lib/defines.js

@@ -59,7 +59,7 @@ var DEBUGGER = true;            // this @define is overridden by the Closure Com
  * but as currently implemented, it does not yield as much improvement as I'd hoped when paging is enabled, so PREFETCH
  * is still off by default.
  */
-var PREFETCH = false;
+var PREFETCH = true;
 
 /**
  * @define {boolean}

modules/pcjs/lib/x86cpu.js

@@ -2190,8 +2190,8 @@ X86CPU.prototype.setIP = function(off)
  */
 X86CPU.prototype.setLIP = function(addr)
 {
-    this.regLIP = addr|0;
+    this.regLIP = addr;
-    this.regLIPLimit = (this.segCS.base + this.segCS.limit)|0;
+    this.regLIPMax = (this.segCS.base >>> 0) + (this.segCS.limit >>> 0) + 1;
 
     /*
      * TODO: Verify the proper source for CPL.  Should it come from segCS.cpl or segCS.dpl?
@@ -2230,8 +2230,7 @@ X86CPU.prototype.setLIP = function(addr)
 X86CPU.prototype.setCSIP = function(off, sel, fCall)
 {
     /*
-     * We break this operation into the following discrete steps (eg, set IP, load CS, and then update IP) so
+     * Setting IP needs to occur AFTER loadCode(), because it may differ from the given IP if sel refers to a gate.
-     * that segCS.load(sel) has the ability to modify IP when sel refers to a gate (call, interrupt, trap, etc).
      */
     var base = this.segCS.loadCode(off, sel, fCall);
     if (base !== X86.ADDR_INVALID) {
@@ -2254,61 +2253,41 @@ X86CPU.prototype.setCSBase = function(addr)
     var regIP = this.getIP();
     addr = this.segCS.setBase(addr);
     this.regLIP = (addr + regIP)|0;
-    this.regLIPLimit = (addr + this.segCS.limit)|0;
+    this.regLIPMax = (addr >>> 0) + (this.segCS.limit >>> 0) + 1;
 };
 
 /**
- * advanceIP(inc)
+ * checkIP(inc)
+ *
+ * TODO: If we didn't care about compatibility, we could just return:
+ *
+ *      (this.regLIP + inc)|0
+ *
+ * and be done with it, because there probably isn't any "good" code that triggers the
+ * "newLIP > this.regLIPMax" condition.  This check costs us about 2Mhz performance on an 80386.
+ *
+ * Turning PREFETCH on tends to offset this performance hit, but PREFETCH *without* this hit would
+ * probably perform even better.
  *
  * @this {X86CPU}
  * @param {number} inc (positive)
+ * @return {number} new LIP
  */
-X86CPU.prototype.advanceIP = function(inc)
+X86CPU.prototype.checkIP = function(inc)
 {
-    // DEBUG: this.assert(inc > 0);
+    var newLIP = (this.regLIP >>> 0) + inc;
-
+    if (newLIP > this.regLIPMax) {
-    this.regLIP = (this.regLIP + inc)|0;
-    /*
-     * Properly comparing regLIP to regLIPLimit would normally require coercing both to unsigned
-     * (ie, floating-point) values.  But instead, we do a subtraction, (regLIPLimit - regLIP), and
-     * if the result is negative, we need only be concerned if the signs of both numbers are the same
-     * (ie, the sign of their XOR'ed union is positive).
-     *
-     * TODO: I'm combining the old 8088 address-wrap check with the new segment-limit check,
-     * even though the correct time to do the latter is immediately BEFORE a fetch, not AFTER; eg,
-     * consider the following code:
-     *
-     *      AX=0100 BX=0015 CX=0080 DX=F859 SP=0A62 BP=0A98 SI=0000 DI=0000
-     *      SS=0038[1759E0,0B5F] DS=02E8[0107A0,017F] ES=0970[009700,6949] A20=ON
-     *      CS=02E0[010080,06FB] LD=0028[000000,0000] GD=[11AEE0,4977] ID=[120082,03FF]
-     *      TR=0010 MS=FFF3 PS=3202 V0 D0 I1 T0 S0 Z0 A0 P0 C0
-     *      02E0:06F9 C20400          RET      0004
-     *
-     * After fetching the 3rd byte of the "RET 0004" instruction at CS:06FB, the CPU wants to automatically
-     * advance IP to 06FC, which of course, exceeds the limit, but that doesn't matter unless we actually
-     * fetch a byte from 06FC, which won't happen.  I'm working around this for now by applying a -1
-     * fudge factor to the fault check below.
-     */
-    if (DEBUG) {
         /*
-         * TODO: This isn't DEBUG code, but it also isn't strictly necessary for properly written code,
+         * There's no such thing as a GP fault on the 8086/8088, and I'm assuming that,
-         * and it hurts performance.  Since this effectively turns advanceIP() into a one-line function for
+         * on newer processors, when the segment limit is the maximum, it's OK for IP to wrap.
-         * non-DEBUG builds, it should automatically get inlined (either at compile-time by the Closure Compiler
-         * or at run-time by whatever JavaScript engine you're using).
          */
-        var off = (this.regLIPLimit - this.regLIP)|0;
+        if (this.model <= X86.MODEL_8088 || this.segCS.limit == this.segCS.maskAddr) {
-        if (off < 0 && (this.regLIPLimit ^ this.regLIP) >= 0) {
+            newLIP = this.segCS.base + ((newLIP - this.regLIPMax) & (I386? this.maskData : 0xffff));
-            /*
+        } else {
-             * There's no such thing as a GP fault on the 8086/8088, and I'm assuming that, on newer
+            X86.helpFault.call(this, X86.EXCEPTION.GP_FAULT, 0);
-             * processors, when the segment limit is set to the maximum, it's OK for IP to wrap.
-             */
-            if (this.model <= X86.MODEL_8088 || this.segCS.limit == this.segCS.maskAddr) {
-                this.setIP(this.regLIP - this.segCS.base);
-            } else if (off < -1) {          // fudge factor
-                X86.helpFault.call(this, X86.EXCEPTION.GP_FAULT, 0);
-            }
         }
     }
+    return newLIP|0;
 };
 
 /**
@@ -3704,9 +3683,10 @@ X86CPU.prototype.refillPrefetch = function()
  */
 X86CPU.prototype.getIPByte = function()
 {
+    var newLIP = this.checkIP(1);
     var b = (PREFETCH? this.getBytePrefetch() : this.getByte(this.regLIP));
     if (BACKTRACK) this.bus.updateBackTrackCode(this.regLIP, this.backTrack.btiMem0);
-    this.advanceIP(1);
+    this.regLIP = newLIP;
     return b;
 };
 
@@ -3718,12 +3698,13 @@ X86CPU.prototype.getIPByte = function()
  */
 X86CPU.prototype.getIPShort = function()
 {
+    var newLIP = this.checkIP(2);
     var w = (PREFETCH? this.getShortPrefetch() : this.getShort(this.regLIP));
     if (BACKTRACK) {
         this.bus.updateBackTrackCode(this.regLIP, this.backTrack.btiMem0);
         this.bus.updateBackTrackCode(this.regLIP + 1, this.backTrack.btiMem1);
     }
-    this.advanceIP(2);
+    this.regLIP = newLIP;
     return w;
 };
 
@@ -3735,6 +3716,7 @@ X86CPU.prototype.getIPShort = function()
  *
 X86CPU.prototype.getIPLong = function()
 {
+    var newLIP = this.checkIP(4);
     var l = (PREFETCH? this.getLongPrefetch() : this.getLong(this.regLIP));
     if (BACKTRACK) {
         this.bus.updateBackTrackCode(this.regLIP, this.backTrack.btiMem0);
@@ -3742,7 +3724,7 @@ X86CPU.prototype.getIPLong = function()
         this.bus.updateBackTrackCode(this.regLIP + 2, this.backTrack.btiMem2);
         this.bus.updateBackTrackCode(this.regLIP + 3, this.backTrack.btiMem3);
     }
-    this.advanceIP(4);
+    this.regLIP = newLIP;
     return l;
 };
  */
@@ -3755,12 +3737,13 @@ X86CPU.prototype.getIPLong = function()
  */
 X86CPU.prototype.getIPAddr = function()
 {
+    var newLIP = this.checkIP(this.sizeAddr);
     var w = (PREFETCH? this.getAddr() : this.getAddr(this.regLIP));
     if (BACKTRACK) {
         this.bus.updateBackTrackCode(this.regLIP, this.backTrack.btiMem0);
         this.bus.updateBackTrackCode(this.regLIP + 1, this.backTrack.btiMem1);
     }
-    this.advanceIP(this.sizeAddr);
+    this.regLIP = newLIP;
     return w;
 };
 
@@ -3772,12 +3755,13 @@ X86CPU.prototype.getIPAddr = function()
  */
 X86CPU.prototype.getIPWord = function()
 {
+    var newLIP = this.checkIP(this.sizeData);
     var w = (PREFETCH? this.getWordPrefetch() : this.getWord(this.regLIP));
     if (BACKTRACK) {
         this.bus.updateBackTrackCode(this.regLIP, this.backTrack.btiMem0);
         this.bus.updateBackTrackCode(this.regLIP + 1, this.backTrack.btiMem1);
     }
-    this.advanceIP(this.sizeData);
+    this.regLIP = newLIP;
     return w;
 };
 
@@ -3789,9 +3773,10 @@ X86CPU.prototype.getIPWord = function()
  */
 X86CPU.prototype.getIPDisp = function()
 {
+    var newLIP = this.checkIP(1);
     var w = ((PREFETCH? this.getBytePrefetch() : this.getByte(this.regLIP)) << 24) >> 24;
     if (BACKTRACK) this.bus.updateBackTrackCode(this.regLIP, this.backTrack.btiMem0);
-    this.advanceIP(1);
+    this.regLIP = newLIP;
     return w;
 };