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First stab at PDP-11 cycle times (11/70 to be precise) is more or less complete now

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This commit is contained in:
Jeff 2016-10-03 14:27:14 -07:00 • committed by Jeff Parsons
commit 2a065f4efc
6 changed files with 491 additions and 445 deletions
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59
modules/pdp11/lib/cpustate.js
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@ -172,10 +172,12 @@ CPUStatePDP11.prototype.initRegs = function()
this.opFlags = 0;
/*
* srcMode and dstMode are set by getVirtualByMode(), indicating to the opcode handlers the mode(s) used
* as part of the current opcode. Ditto for srcReg and dstReg.
* srcMode and srcReg are set by getVirtualByMode() for reads, and dstMode and dstReg are set for writes/updates.
* indicating to the opcode handlers the mode(s) and register(s) used as part of the current opcode, so that they
* can calculate the correct number of cycles. dstAddr is set for byte operations that also need to know the
* effective address for their cycle calculation.
*/
this.srcMode = this.dstMode = 0;
this.srcMode = this.dstMode = this.dstAddr = 0;
this.srcReg = this.dstReg = 0;
this.cpuType = 70;
@ -1335,16 +1337,18 @@ CPUStatePDP11.prototype.getVirtualByMode = function(addressMode, accessFlags)
}
/*
* Modes that need to auto-increment or auto-decrement will break,
* n order to perform the update; others will return an address immediately.
* Modes that need to auto-increment or auto-decrement will break, in order to perform the
* update; others will return an address immediately.
*/
switch (mode) {
/*
* Mode 0: Registers don't have a virtual address, so trap.
* TODO: Review whether we should ever actually hit this code path (hence the assert).
*
* NOTE: Most instruction code paths never call getVirtualByMode() when the mode is zero;
* JMP and JSR instructions are exceptions, but that's OK, because those are documented to
* "cause an 'illegal' instruction" condition", which we interpret to mean a BUS_ERROR trap.
*/
case 0:
this.assert(false);
this.trap(PDP11.TRAP.BUS_ERROR, PDP11.REASON.NOREGADDR);
return 0;
@ -1363,7 +1367,7 @@ CPUStatePDP11.prototype.getVirtualByMode = function(addressMode, accessFlags)
this.opFlags |= PDP11.OPFLAG.TRAP_SP;
}
}
this.nStepCycles -= 2 + 1;
this.nStepCycles -= (2 + 1);
return (reg === 7? this.regsGen[reg] : (this.regsGen[reg] | addrDSpace));
/*
@ -1378,7 +1382,7 @@ CPUStatePDP11.prototype.getVirtualByMode = function(addressMode, accessFlags)
stepSize = 1;
}
}
this.nStepCycles -= 2 + 1;
this.nStepCycles -= (2 + 1);
break;
/*
@ -1391,7 +1395,7 @@ CPUStatePDP11.prototype.getVirtualByMode = function(addressMode, accessFlags)
virtualAddress = this.readWordFromVirtual(virtualAddress);
// if (reg === 7) LOG_ADDRESS(virtualAddress); // @#n not operational
virtualAddress |= addrDSpace;
this.nStepCycles -= 5 + 2;
this.nStepCycles -= (5 + 2);
break;
/*
@ -1402,7 +1406,7 @@ CPUStatePDP11.prototype.getVirtualByMode = function(addressMode, accessFlags)
if (reg < 6 && (accessFlags & PDP11.ACCESS.BYTE)) stepSize = -1;
virtualAddress = (this.regsGen[reg] + stepSize) & 0xffff;
if (reg !== 7) virtualAddress |= addrDSpace;
this.nStepCycles -= 3 + 1;
this.nStepCycles -= (3 + 1);
break;
/*
@ -1413,7 +1417,7 @@ CPUStatePDP11.prototype.getVirtualByMode = function(addressMode, accessFlags)
virtualAddress = (this.regsGen[reg] - 2) & 0xffff;
if (reg !== 7) virtualAddress |= addrDSpace;
virtualAddress = this.readWordFromVirtual(virtualAddress) | addrDSpace;
this.nStepCycles -= 6 + 2;
this.nStepCycles -= (6 + 2);
break;
/*
@ -1422,7 +1426,7 @@ CPUStatePDP11.prototype.getVirtualByMode = function(addressMode, accessFlags)
case 6:
virtualAddress = this.getPCWord();
virtualAddress = ((virtualAddress + this.regsGen[reg]) & 0xffff) | addrDSpace;
this.nStepCycles -= 4 + 2;
this.nStepCycles -= (4 + 2);
return virtualAddress;
/*
@ -1432,7 +1436,7 @@ CPUStatePDP11.prototype.getVirtualByMode = function(addressMode, accessFlags)
virtualAddress = this.getPCWord();
virtualAddress = (virtualAddress + this.regsGen[reg]) & 0xffff;
virtualAddress = this.readWordFromVirtual(virtualAddress | PDP11.ACCESS.DSPACE) | addrDSpace;
this.nStepCycles -= 7 + 3;
this.nStepCycles -= (7 + 3);
return virtualAddress;
}
@ -1496,7 +1500,7 @@ CPUStatePDP11.prototype.readWordFromPrevSpace = function(opCode, accessFlags)
var src;
if (!(opCode & PDP11.OPMODE.MASK)) {
this.srcMode = 0;
var reg = opCode & PDP11.OPREG.MASK;
var reg = this.srcReg = opCode & PDP11.OPREG.MASK;
if (reg != 6 || ((this.regPSW >> 2) & PDP11.PSW.PMODE) === (this.regPSW & PDP11.PSW.PMODE)) {
src = this.regsGen[reg];
} else {
@ -1529,7 +1533,7 @@ CPUStatePDP11.prototype.writeWordToPrevSpace = function(opCode, accessFlags, dat
}
if (!(opCode & PDP11.OPMODE.MASK)) {
this.dstMode = 0;
var reg = opCode & PDP11.OPREG.MASK;
var reg = this.dstReg = opCode & PDP11.OPREG.MASK;
if (reg != 6 || ((this.regPSW >> 2) & PDP11.PSW.PMODE) === (this.regPSW & PDP11.PSW.PMODE)) {
this.regsGen[reg] = data;
} else {
@ -1557,7 +1561,7 @@ CPUStatePDP11.prototype.readWordByMode = function(addressMode)
var result;
if (!(addressMode & PDP11.OPMODE.MASK)) {
this.srcMode = 0;
result = this.regsGen[addressMode & PDP11.OPREG.MASK];
result = this.regsGen[this.srcReg = addressMode & PDP11.OPREG.MASK];
} else {
/*
* NOTE: This used to call readWordFromPhysical(), after calling getAddrVirtual(), but the latter is
@ -1581,7 +1585,7 @@ CPUStatePDP11.prototype.readByteByMode = function(addressMode)
var result;
if (!(addressMode & PDP11.OPMODE.MASK)) {
this.srcMode = 0;
result = this.regsGen[addressMode & PDP11.OPREG.MASK] & 0xff;
result = this.regsGen[this.srcReg = addressMode & PDP11.OPREG.MASK] & 0xff;
} else {
result = this.readByteFromPhysical(this.getAddr(addressMode, PDP11.ACCESS.READ_BYTE));
}
@ -1602,7 +1606,7 @@ CPUStatePDP11.prototype.updateWordByMode = function(addressMode, src, fnOp)
{
if (!(addressMode & PDP11.OPMODE.MASK)) {
this.dstMode = 0;
var reg = addressMode & PDP11.OPREG.MASK;
var reg = this.dstReg = addressMode & PDP11.OPREG.MASK;
this.regsGen[reg] = fnOp.call(this, src, this.regsGen[reg]);
} else {
var addr = this.getAddr(addressMode, PDP11.ACCESS.UPDATE_WORD);
@ -1624,10 +1628,10 @@ CPUStatePDP11.prototype.updateByteByMode = function(addressMode, src, fnOp)
{
if (!(addressMode & PDP11.OPMODE.MASK)) {
this.dstMode = 0;
var reg = addressMode & PDP11.OPREG.MASK;
var reg = this.dstReg = addressMode & PDP11.OPREG.MASK;
this.regsGen[reg] = (this.regsGen[reg] & 0xff00) | fnOp.call(this, src, this.regsGen[reg]);
} else {
var addr = this.getAddr(addressMode, PDP11.ACCESS.UPDATE_BYTE);
var addr = this.dstAddr = this.getAddr(addressMode, PDP11.ACCESS.UPDATE_BYTE);
this.writeByteToPhysical(addr, fnOp.call(this, src, this.readByteFromPhysical(addr)));
}
};
@ -1646,7 +1650,7 @@ CPUStatePDP11.prototype.writeWordByMode = function(addressMode, data)
{
if (!(addressMode & PDP11.OPMODE.MASK)) {
this.dstMode = 0;
this.regsGen[addressMode & PDP11.OPREG.MASK] = data & 0xffff;
this.regsGen[this.dstReg = addressMode & PDP11.OPREG.MASK] = data & 0xffff;
} else {
this.writeWordToPhysical(this.getAddr(addressMode, PDP11.ACCESS.WRITE_WORD), data);
}
@ -1668,7 +1672,7 @@ CPUStatePDP11.prototype.writeByteByMode = function(addressMode, data, writeFlags
{
if (!(addressMode & PDP11.OPMODE.MASK)) {
this.dstMode = 0;
var reg = addressMode & PDP11.OPREG.MASK;
var reg = this.dstReg = addressMode & PDP11.OPREG.MASK;
if (!data) {
this.regsGen[reg] &= ~0xff; // TODO: Profile to determine if this is a win
} else if (writeFlags & PDP11.WRITE.SIGNEXT) {
@ -1687,10 +1691,15 @@ CPUStatePDP11.prototype.writeByteByMode = function(addressMode, data, writeFlags
*
* @this {CPUStatePDP11}
* @param {number} opCode
* @param {boolean|number} condition
*/
CPUStatePDP11.prototype.branch = function(opCode)
CPUStatePDP11.prototype.branch = function(opCode, condition)
{
this.setPC(this.regsGen[PDP11.REG.PC] + ((opCode << 24) >> 23));
if (condition) {
this.setPC(this.getPC() + ((opCode << 24) >> 23));
this.nStepCycles -= 2;
}
this.nStepCycles -= (2 + 1);
};
/**