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This commit is contained in:
Jeff Parsons 2015-04-20 22:43:27 -07:00 • committed by jeffpar
commit ea04535880
2 changed files with 8 additions and 28 deletions
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2
modules/pcjs/lib/x86op0f.js
View file

@ -1272,7 +1272,7 @@ X86.aOps0F[0x05] = X86.opLOADALL;
X86.aOps0F[0x06] = X86.opCLTS;
/*
* On all processors (except the 8086/8088, of course), 0x0F,0x0B is also referred to as "UD2": an
* On all processors (except the 8086/8088, of course), X86.OPCODE.UD2 (0x0F,0x0B), aka "UD2", is an
* instruction guaranteed to raise a #UD (Invalid Opcode) exception (INT 0x06) on all future x86 processors.
*/
X86.aOps0F[0x0B] = X86.opInvalid;

34
modules/pcjs/lib/x86ops.js
View file

@ -3263,24 +3263,7 @@ X86.opMOVw = function MOVw()
};
/**
* op=0xC8 (ENTER imm,imm8) (80186/80188 and up)
*
* Here's the pseudo-code from http://www.pcjs.org/pubs/pc/reference/intel/80286/progref, p.B-40 (p.250):
*
* LEVEL := LEVEL MOD 32
* Push BP
* Set a temporary value FRAME_PTR := SP
* If LEVEL > 0 then
* Repeat (LEVEL-1) times:
* BP := BP - 2
* Push the word pointed to by BP
* End repeat
* Push FRAME_PTR
* End if
* BP := FRAME_PTR
* SP := SP - first operand
*
* TODO: Verify that this pseudo-code is identical on the 80186/80188 (eg, is LEVEL MOD 32 performed in both instances?)
* op=0xC8 (ENTER imm16,imm8) (80186/80188 and up)
*
* @this {X86CPU}
*/
@ -3294,24 +3277,22 @@ X86.opENTER = function ENTER()
*/
this.nStepCycles -= 11;
this.pushWord(this.regEBP);
var wFrame = this.getSP() & this.segSS.addrMask;
var wFrame = this.getSP() & this.dataMask;
if (bLevel > 0) {
this.nStepCycles -= (bLevel << 2) + (bLevel > 1? 1 : 0);
while (--bLevel) {
this.regEBP = (this.regEBP & ~this.segSS.addrMask) | ((this.regEBP - this.dataSize) & this.segSS.addrMask);
this.pushWord(this.getSOWord(this.segSS, this.regEBP & this.segSS.addrMask));
this.regEBP = (this.regEBP & ~this.dataMask) | ((this.regEBP - this.dataSize) & this.dataMask);
this.pushWord(this.getSOWord(this.segSS, this.regEBP & this.dataMask));
}
this.pushWord(wFrame);
}
this.regEBP = (this.regEBP & ~this.segSS.addrMask) | wFrame;
this.regEBP = (this.regEBP & ~this.dataMask) | wFrame;
this.setSP((this.getSP() & ~this.segSS.addrMask) | ((this.getSP() - wLocal) & this.segSS.addrMask));
};
/**
* op=0xC9 (LEAVE) (80186/80188 and up)
*
* Set SP to BP, then pop BP.
*
* @this {X86CPU}
*/
X86.opLEAVE = function LEAVE()
@ -3489,7 +3470,7 @@ X86.opAAD = function AAD()
*
* Sets AL to 0xFF if CF=1, 0x00 otherwise; no flags are affected (similar to SBB AL,AL, but without side-effects)
*
* WARNING: I have no idea how many clocks this instruction originally consumed, so for now, I'm going with the minimum of 2.
* WARNING: I have no idea how many clocks this instruction originally required, so for now, I'm going with a minimum of 2.
*
* @this {X86CPU}
*/
@ -3581,7 +3562,7 @@ X86.opLOOP = function LOOP()
X86.opJCXZ = function JCXZ()
{
var disp = this.getIPDisp();
if (!this.regECX) {
if (!(this.regECX & this.addrMask)) {
this.setIP(this.getIP() + disp);
this.nStepCycles -= this.cycleCounts.nOpCyclesLoopZ;
return;
@ -3833,7 +3814,6 @@ X86.opHLT = function HLT()
if (!this.getIF()) {
if (DEBUGGER && this.dbg) this.advanceIP(-1);
this.stopCPU();
// return;
}
};