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Fixed read/write breakpoints for instructions that snapshot the cycle count, and improved the disassembly of PC-relative operands

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Jeff Parsons 2016-10-21 13:45:01 -07:00 • committed by Jeff Parsons
commit 22e24697fe
5 changed files with 286 additions and 263 deletions
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13
modules/pdp11/lib/cpu.js
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@ -530,7 +530,7 @@ CPUPDP11.prototype.addCycles = function(nCycles, fEndStep)
{
this.nTotalCycles += nCycles;
if (fEndStep) {
this.nBurstCycles = this.nStepCycles = 0;
this.nBurstCycles = this.nStepCycles = this.nSnapCycles = 0;
}
};
@ -643,7 +643,7 @@ CPUPDP11.prototype.resetCycles = function()
{
this.mhz = 0;
this.nYieldsSinceStatusUpdate = 0;
this.nTotalCycles = this.nRunCycles = this.nBurstCycles = this.nStepCycles = 0;
this.nTotalCycles = this.nRunCycles = this.nBurstCycles = this.nStepCycles = this.nSnapCycles = 0;
this.resetChecksum();
this.setSpeed(1);
};
@ -1019,7 +1019,13 @@ CPUPDP11.prototype.updateTimers = function(nCycles)
CPUPDP11.prototype.endBurst = function(fReset)
{
var nCycles = this.nBurstCycles -= this.nStepCycles;
this.nStepCycles = 0;
/*
* In addition to zeroing nStepCycles, it's important that we also zero nSnapCycles, because if a CPU
* burst is being ended after nStepCycles has been "snapped" (because a certain opcode has an unusual timing
* calculation that must be based on a "snapped" cycle count rather the opcode's starting cycle count), we
* could inadvertently undo the endBurst() if the original "snapped" value was used to update nStepCycles.
*/
this.nStepCycles = this.nSnapCycles = 0;
if (fReset) this.nBurstCycles = 0;
return nCycles;
};
@ -1190,7 +1196,6 @@ CPUPDP11.prototype.yieldCPU = function()
{
this.endBurst(); // this will break us out of stepCPU()
this.nCyclesNextYield = 0; // this will break us out of runCPU(), once we break out of stepCPU()
// if (DEBUG) this.nSnapCycles = this.nBurstCycles;
/*
* The Debugger calls yieldCPU() after every message() to ensure browser responsiveness, but it looks
* odd for those messages to show CPU state changes if the Control Panel, Video display, etc, does not,