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This commit is contained in:
Jeff Parsons 2015-02-02 14:36:30 -08:00 • committed by jeffpar
commit 2cd13b2058
11 changed files with 2808 additions and 2743 deletions
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30
modules/pcjs/lib/x86seg.js
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@ -1,5 +1,5 @@
/**
* @fileoverview Implements PCjs X86 Segment objects
* @fileoverview Implements PCjs X86 Segment Registers
* @author <a href="mailto:Jeff@pcjs.org">Jeff Parsons</a>
* @version 1.0
* Created 2014-Sep-10
@ -45,7 +45,7 @@ if (typeof module !== 'undefined') {
* @constructor
* @param {X86CPU} cpu
* @param {number} id
* @param {string} [sName] segment name
* @param {string} [sName] segment register name
* @param {boolean} [fProt] true if segment register used exclusively in protected-mode (eg, segLDT)
*/
function X86Seg(cpu, id, sName, fProt)
@ -81,12 +81,17 @@ function X86Seg(cpu, id, sName, fProt)
* As long as setCSIP() or opHelpINT() are used for all CS changes, fCall is set automatically.
*
* TODO: Consider making fCall a parameter to load(), instead of a property that must be set prior to
* calling load(); the downside (and why I didn't do that in the first place) is that such a parameter
* is meaningless for segments other than segCS.
* calling load(); the downside is that such a parameter is meaningless for segments other than segCS.
*/
this.awParms = (this.id == X86Seg.ID.CODE? new Array(32) : []);
this.fCall = null;
this.fStackSwitch = false;
/*
* The following properties are used for STACK segments only (ie, segSS); we want to make it easier
* for setSS() to set stack lower and upper limits, which requires knowing whether or not the segment is
* marked as EXPDOWN.
*/
this.fExpDown = false;
this.updateMode(fProt);
}
@ -117,6 +122,7 @@ X86Seg.ID = {
*/
X86Seg.loadReal = function loadReal(sel, fSuppress)
{
this.cpu.assert(!(sel & ~0xffff));
this.sel = sel;
this.dataSize = this.addrSize = 2;
this.dataMask = this.addrMask = 0xffff;
@ -152,6 +158,8 @@ X86Seg.loadProt = function loadProt(sel, fSuppress)
var addrDTLimit;
var cpu = this.cpu;
this.cpu.assert(!(sel & ~0xffff));
if (!(sel & X86.SEL.LDT)) {
addrDT = cpu.addrGDT;
addrDTLimit = cpu.addrGDTLimit;
@ -166,8 +174,8 @@ X86Seg.loadProt = function loadProt(sel, fSuppress)
* grief here. We avoid that grief by 1) relying on the Debugger setting fSuppress to true, and 2) skipping
* segment lookup if the descriptor table being referenced is zero.
*
* TODO: This could probably be simplified to a test of addrDT; please note, however, that there's nothing
* in the design of the CPU that prevents the GDT or LDT being located at physical address zero.
* TODO: This could probably be simplified to a test of addrDT; however, there's nothing in the design
* of the CPU that prevents the GDT or LDT being located at physical address zero.
*/
if (!fSuppress || addrDT) {
var addrDesc = addrDT + (sel & X86.SEL.MASK);
@ -193,7 +201,7 @@ X86Seg.loadProt = function loadProt(sel, fSuppress)
*
* @this {X86Seg}
* @param {number} nIDT
* @return {number} address from selected veector, or ADDR_INVALID if error (TODO: No error conditions exist yet)
* @return {number} address from selected vector, or ADDR_INVALID if error (TODO: No error conditions exist yet)
*/
X86Seg.loadIDTReal = function loadIDTReal(nIDT)
{
@ -455,7 +463,7 @@ X86Seg.switchTSS = function switchTSS(selNew, fNest)
offSP = (this.cpl << 2) + X86.TSS.CPL0_SP;
offSS = offSP + 2;
}
cpu.setSS(cpu.getShort(addrNew + offSS)); // TODO: Do we care that cpu.setSS() -- unlike segSS.load() -- will also set X86.OPFLAG.NOINTR?
cpu.setSS(cpu.getShort(addrNew + offSS), true);
cpu.setSP(cpu.getShort(addrNew + offSP));
cpu.segLDT.load(cpu.getShort(addrNew + X86.TSS.TASK_LDT));
if (fNest) cpu.setShort(addrNew + X86.TSS.PREV_TSS, selOld);
@ -592,7 +600,7 @@ X86Seg.prototype.loadDesc8 = function(addrDesc, sel, fSuppress)
break;
}
regSP = cpu.popWord();
cpu.setSS(cpu.popWord()); // TODO: Do we care that cpu.setSS() -- unlike segSS.load() -- will also set X86.OPFLAG.NOINTR?
cpu.setSS(cpu.popWord(), true);
cpu.setSP(regSP);
this.fStackSwitch = true;
}
@ -659,7 +667,7 @@ X86Seg.prototype.loadDesc8 = function(addrDesc, sel, fSuppress)
offSS = offSP + 2;
regSSPrev = cpu.getSS();
regSPPrev = cpu.getSP();
cpu.setSS(cpu.getShort(addrTSS + offSS)); // TODO: Do we care that cpu.setSS() -- unlike segSS.load() -- will also set X86.OPFLAG.NOINTR?
cpu.setSS(cpu.getShort(addrTSS + offSS), true);
cpu.setSP(cpu.getShort(addrTSS + offSP));
cpu.pushWord(regSSPrev);
cpu.pushWord(regSPPrev);
@ -819,6 +827,7 @@ X86Seg.prototype.updateMode = function(fProt)
if (fProt === undefined) {
fProt = !!(this.cpu.regMSW & X86.MSW.PE);
}
this.fExpDown = false;
if (fProt) {
this.load = X86Seg.loadProt;
this.loadIDT = X86Seg.loadIDTProt;
@ -843,6 +852,7 @@ X86Seg.prototype.updateMode = function(fProt)
if ((this.acc & (X86.DESC.ACC.TYPE.CODE | X86.DESC.ACC.TYPE.EXPDOWN)) == X86.DESC.ACC.TYPE.EXPDOWN) {
if (this.checkRead == X86Seg.checkReadProt) this.checkRead = X86Seg.checkReadProtDown;
if (this.checkWrite == X86Seg.checkWriteProt) this.checkWrite = X86Seg.checkWriteProtDown;
this.fExpDown = true;
}
}
this.cpl = this.sel & X86.SEL.RPL;