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Implemented INC/DEC opcodes

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This commit is contained in:
Jeff 2016-09-27 09:28:52 -07:00 • committed by Jeff Parsons
commit e322c5f912
3 changed files with 133 additions and 50 deletions
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55
modules/pdp11/lib/cpustate.js
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@ -512,7 +512,7 @@ CPUStatePDP11.prototype.getPC = function()
*/
CPUStatePDP11.prototype.setPC = function(addr)
{
this.regsGen[7] = addr;
this.regsGen[7] = addr & 0xffff;
};
/**
@ -526,6 +526,17 @@ CPUStatePDP11.prototype.getSP = function()
return this.regsGen[6];
};
/**
* setSP()
*
* @this {CPUStatePDP11}
* @param {number} addr
*/
CPUStatePDP11.prototype.setSP = function(addr)
{
this.regsGen[6] = addr & 0xffff;
};
/**
* requestHALT()
*
@ -702,6 +713,8 @@ CPUStatePDP11.prototype.setPSW = function(newPSW)
/**
* updateNZCFlags(result)
*
* NOTE: The V flag is simply zeroed, it is not "updated" based on the result.
*
* @this {CPUStatePDP11}
* @param {number} result
*/
@ -716,6 +729,8 @@ CPUStatePDP11.prototype.updateNZCFlags = function(result)
/**
* updateNZFlags(result)
*
* NOTE: The V flag is simply zeroed, it is not "updated" based on the result.
*
* @this {CPUStatePDP11}
* @param {number} result
*/
@ -743,6 +758,44 @@ CPUStatePDP11.prototype.updateAddFlags = function(result, src, dst)
}
};
/**
* updateIncFlags(result, src, dst)
*
* NOTE: We could have used updateAddFlags() if not for the fact that the C flag must be preserved.
*
* @this {CPUStatePDP11}
* @param {number} result (dst + src)
* @param {number} src (ie, 1)
* @param {number} dst
*/
CPUStatePDP11.prototype.updateIncFlags = function(result, src, dst)
{
if (!(this.opFlags & PDP11.OPFLAG.SKIP_FLAGS)) {
this.flagN = this.flagZ = result;
// Because src is always 1 (with a zero sign bit), it can be optimized out of this calculation
this.flagV = (/* src ^ */ result) & (dst ^ result);
}
};
/**
* updateDecFlags(result, src, dst)
*
* NOTE: We could have used updateSubFlags() if not for the fact that the C flag must be preserved.
*
* @this {CPUStatePDP11}
* @param {number} result (dst - src)
* @param {number} src (ie, 1)
* @param {number} dst
*/
CPUStatePDP11.prototype.updateDecFlags = function(result, src, dst)
{
if (!(this.opFlags & PDP11.OPFLAG.SKIP_FLAGS)) {
this.flagN = this.flagZ = result;
// Because src is always 1 (with a zero sign bit), it can be optimized out of this calculation
this.flagV = (/* src ^ */ dst) & (dst ^ result);
}
};
/**
* updateSubFlags(result, src, dst)
*