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Starting on 1.16.1

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This commit is contained in:
Jeff Parsons 2014-11-29 08:29:25 -08:00 • committed by jeffpar
commit 6248972684
121 changed files with 1261 additions and 1091 deletions
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66
modules/pcjs/lib/x86seg.js
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@ -50,6 +50,7 @@ if (typeof module !== 'undefined') {
function X86Seg(cpu, id, sName, fProt)
{
this.cpu = cpu;
this.dbg = cpu.dbg;
this.id = id;
this.sName = sName || "";
this.sel = 0;
@ -154,18 +155,30 @@ X86Seg.loadProt = function loadProt(sel, fSuppress)
addrDT = cpu.segLDT.base;
addrDTLimit = addrDT + cpu.segLDT.limit;
}
var addrDesc = addrDT + (sel & X86.SEL.MASK);
if (addrDesc + 7 <= addrDTLimit) {
/*
* TODO: This is only the first of many steps toward accurately counting cycles in protected mode;
* I simply noted that "POP segreg" takes 5 cycles in real mode and 20 in protected mode, so I'm
* starting with a 15-cycle difference. Obviously the difference will be much greater when the load fails.
*/
if (!fSuppress) cpu.nStepCycles -= 15;
return this.loadDesc8(addrDesc, sel);
}
if (!fSuppress) {
X86Help.opHelpFault.call(this.cpu, X86.EXCEPTION.GP_FAULT, sel);
/*
* The ROM BIOS POST executes some test code in protected-mode without properly initializing the LDT,
* which has no bearing on the ROM's own code, because it never loads any LDT selectors, but if at the same
* time our Debugger attempts to validate a selector in one of its breakpoints, that could cause some
* 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.
*/
if (!fSuppress || addrDT) {
var addrDesc = addrDT + (sel & X86.SEL.MASK);
if (addrDesc + 7 <= addrDTLimit) {
/*
* TODO: This is only the first of many steps toward accurately counting cycles in protected mode;
* I simply noted that "POP segreg" takes 5 cycles in real mode and 20 in protected mode, so I'm
* starting with a 15-cycle difference. Obviously the difference will be much greater when the load fails.
*/
if (!fSuppress) cpu.nStepCycles -= 15;
return this.loadDesc8(addrDesc, sel, fSuppress);
}
if (!fSuppress) {
X86Help.opHelpFault.call(cpu, X86.EXCEPTION.GP_FAULT, sel);
}
}
return null;
};
@ -214,7 +227,7 @@ X86Seg.loadProtIDT = function loadProtIDT(nIDT)
if (addrDesc + 7 <= cpu.addrIDTLimit) {
return this.loadDesc8(addrDesc, nIDT);
}
X86Help.opHelpFault.call(this.cpu, X86.EXCEPTION.GP_FAULT, nIDT | X86.ERRCODE.IDT | X86.ERRCODE.EXT, true);
X86Help.opHelpFault.call(cpu, X86.EXCEPTION.GP_FAULT, nIDT | X86.ERRCODE.IDT | X86.ERRCODE.EXT, true);
return null;
};
@ -383,8 +396,8 @@ X86Seg.switchTSS = function switchTSS(selNew, fNest)
return false;
}
var addrNew = cpu.segTSS.base;
if (DEBUG) {
cpu.messageDebugger((fNest? "Task switch" : "Task return") + ": TR " + str.toHexWord(selOld) + " (%" + str.toHex(addrOld, 6) + "), new TR " + str.toHexWord(selNew) + " (%" + str.toHex(addrNew, 6) + ")", Debugger.MESSAGE.TSS);
if (DEBUG && DEBUGGER && this.dbg && this.dbg.messageEnabled(Debugger.MESSAGE.TSS)) {
this.dbg.message((fNest? "Task switch" : "Task return") + ": TR " + str.toHexWord(selOld) + " (%" + str.toHex(addrOld, 6) + "), new TR " + str.toHexWord(selNew) + " (%" + str.toHex(addrNew, 6) + ")");
}
if (fNest) {
if (cpu.segTSS.type == X86.DESC.ACC.TYPE.TSS_BUSY) {
@ -503,7 +516,7 @@ X86Seg.prototype.loadDesc6 = function(addrDesc, sel)
};
/**
* loadDesc8(addrDesc, sel)
* loadDesc8(addrDesc, sel, fSuppress)
*
* Used to load a protected-mode selector that refers to an 8-byte "descriptor table" (GDT, LDT, IDT) entry:
*
@ -517,9 +530,10 @@ X86Seg.prototype.loadDesc6 = function(addrDesc, sel)
* @this {X86Seg}
* @param {number} addrDesc is the descriptor address
* @param {number} sel is the associated selector
* @param {boolean} [fSuppress] is true to suppress any errors, cycle assessment, etc
* @return {number|null} base address of selected segment, or null if error
*/
X86Seg.prototype.loadDesc8 = function(addrDesc, sel)
X86Seg.prototype.loadDesc8 = function(addrDesc, sel, fSuppress)
{
var cpu = this.cpu;
var limit = cpu.getWord(addrDesc + X86.DESC.LIMIT.OFFSET);
@ -599,7 +613,7 @@ X86Seg.prototype.loadDesc8 = function(addrDesc, sel)
return this.base;
}
if (DEBUG) cpu.assert(false);
X86Help.opHelpFault.call(cpu, X86.EXCEPTION.GP_FAULT, sel, true);
if (!fSuppress) X86Help.opHelpFault.call(cpu, X86.EXCEPTION.GP_FAULT, sel, true);
base = null;
break;
}
@ -644,7 +658,7 @@ X86Seg.prototype.loadDesc8 = function(addrDesc, sel)
return this.base;
}
if (DEBUG) cpu.assert(false);
X86Help.opHelpFault.call(cpu, X86.EXCEPTION.GP_FAULT, sel | X86.ERRCODE.EXT, true);
if (!fSuppress) X86Help.opHelpFault.call(cpu, X86.EXCEPTION.GP_FAULT, sel | X86.ERRCODE.EXT, true);
base = null;
break;
}
@ -656,7 +670,7 @@ X86Seg.prototype.loadDesc8 = function(addrDesc, sel)
return this.base;
}
else {
X86Help.opHelpFault.call(this.cpu, X86.EXCEPTION.GP_FAULT, sel, true);
if (!fSuppress) X86Help.opHelpFault.call(cpu, X86.EXCEPTION.GP_FAULT, sel, true);
base = null;
break;
}
@ -665,7 +679,7 @@ X86Seg.prototype.loadDesc8 = function(addrDesc, sel)
else if (this.id == X86Seg.ID.DATA) {
if (selMasked) {
if (type < X86.DESC.ACC.TYPE.DATA_READONLY || (type & (X86.DESC.ACC.TYPE.CODE | X86.DESC.ACC.TYPE.READABLE)) == X86.DESC.ACC.TYPE.CODE) {
X86Help.opHelpFault.call(this.cpu, X86.EXCEPTION.GP_FAULT, sel, true);
if (!fSuppress) X86Help.opHelpFault.call(cpu, X86.EXCEPTION.GP_FAULT, sel, true);
base = null;
break;
}
@ -673,14 +687,14 @@ X86Seg.prototype.loadDesc8 = function(addrDesc, sel)
}
else if (this.id == X86Seg.ID.STACK) {
if (!selMasked || type < X86.DESC.ACC.TYPE.DATA_READONLY || (type & (X86.DESC.ACC.TYPE.CODE | X86.DESC.ACC.TYPE.READABLE)) == X86.DESC.ACC.TYPE.CODE) {
X86Help.opHelpFault.call(this.cpu, X86.EXCEPTION.GP_FAULT, sel, true);
if (!fSuppress) X86Help.opHelpFault.call(cpu, X86.EXCEPTION.GP_FAULT, sel, true);
base = null;
break;
}
}
else if (this.id == X86Seg.ID.TSS) {
if (!selMasked || type != X86.DESC.ACC.TYPE.TSS && type != X86.DESC.ACC.TYPE.TSS_BUSY) {
X86Help.opHelpFault.call(this.cpu, X86.EXCEPTION.TS_FAULT, sel, true);
if (!fSuppress) X86Help.opHelpFault.call(cpu, X86.EXCEPTION.TS_FAULT, sel, true);
base = null;
break;
}
@ -703,7 +717,7 @@ X86Seg.prototype.loadDesc8 = function(addrDesc, sel)
this.updateMode();
break;
}
this.messageDebugger(sel, base, limit, acc, ext);
if (!fSuppress) this.messageDebugger(sel, base, limit, acc, ext);
return base;
};
@ -830,11 +844,11 @@ X86Seg.prototype.updateMode = function(fProt)
X86Seg.prototype.messageDebugger = function(sel, base, limit, acc, ext)
{
if (DEBUG) {
if (DEBUGGER) {
if (DEBUGGER && this.dbg && this.dbg.messageEnabled(Debugger.MESSAGE.SEG)) {
var ch = (this.sName.length < 3? " " : "");
var sDPL = " dpl=" + this.dpl;
if (this.id == X86Seg.ID.CODE) sDPL += " cpl=" + this.cpl;
this.cpu.messageDebugger("loadSeg(" + this.sName + "):" + ch + "sel=" + str.toHexWord(sel) + " base=" + str.toHex(base) + " limit=" + str.toHexWord(limit) + " acc=" + str.toHexWord(acc) + sDPL, Debugger.MESSAGE.SEG);
this.dbg.message("loadSeg(" + this.sName + "):" + ch + "sel=" + str.toHexWord(sel) + " base=" + str.toHex(base) + " limit=" + str.toHexWord(limit) + " acc=" + str.toHexWord(acc) + sDPL);
}
this.cpu.assert(/* base != null && */ (!ext || ext == X86.DESC.EXT.AVAIL));
}