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Improved separation of FDC media parameters from drive parameters

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This commit is contained in:
Jeff Parsons 2014-10-20 00:24:13 -05:00 • committed by jeffpar
commit 1809543577
32 changed files with 1915 additions and 1887 deletions
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20
my_modules/pcjs-client/lib/x86help.js
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@ -34,8 +34,8 @@
"use strict";
if (typeof module !== 'undefined') {
var X86 = require("./x86");
var Debugger = require("./debugger");
var X86 = require("./x86");
var Debugger = require("./debugger");
}
var X86Help = {
@ -127,14 +127,14 @@ var X86Help = {
* @param {number} dst
* @param {number} src
* @return {number}
*
*
* 80286_and_80287_Programmers_Reference_Manual_1987.pdf, p.B-44 (p.254) notes that:
*
*
* "The low 16 bits of the product of a 16-bit signed multiply are the same as those of an
* unsigned multiply. The three operand IMUL instruction can be used for unsigned operands as well."
*
*
* However, we still sign-extend the operands before multiplying, making it easier to range-check the result.
*
*
* (80186/80188 and up)
*/
opHelpIMUL16: function(dst, src) {
@ -237,8 +237,8 @@ var X86Help = {
if (wIndex < wLower || wIndex > wUpper) {
/*
* The INT 0x05 handler must be called with CS:IP pointing to the BOUND instruction.
*
* TODO: Determine the cycle impact when a BOUND exception is triggered, over and above nOpCyclesBound.
*
* TODO: Determine the cycle impact when a BOUND exception is triggered, over and above nOpCyclesBound.
*/
this.setIP(this.opEA - this.segCS.base);
X86Help.opHelpINT.call(this, X86.EXCEPTION.BOUND_ERR, null, 0);
@ -273,7 +273,7 @@ var X86Help = {
/*
* Currently, segVER.load() will return an error only if the selector is beyond the bounds of the
* descriptor table or the descriptor is not for a segment.
*
*
* TODO: This instruction's 80286 documentation does not discuss conforming code segments; determine
* if we need a special check for them.
*/
@ -297,7 +297,7 @@ var X86Help = {
/*
* Currently, segVER.load() will return an error only if the selector is beyond the bounds of the
* descriptor table or the descriptor is not for a segment.
*
*
* TODO: LSL is explicitly documented as ALSO requiring a non-null selector, so we check X86.SEL.MASK;
* are there any other instructions that were, um, less explicit but also require a non-null selector?
*/