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Added ROT and ROTC (albeit untested)

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This commit is contained in:
Jeff 2017-03-03 21:09:45 -08:00 • committed by Jeff Parsons
commit 88f66f9590
3 changed files with 163 additions and 110 deletions
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59
modules/pdp10/lib/cpuops.js
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@ -1368,7 +1368,12 @@ PDP10.opASH = function(op, acc)
};
/**
* opROT(0o241000)
* opROT(0o241000): Rotate
*
* From the DEC PDP-10 System Reference Manual (May 1968), p. 2-25:
*
* Rotate AC the number of places specified by E. If E is positive, rotate left; bit 0 is rotated
* into bit 35. If E is negative, rotate right; bit 35 is rotated into bit O.
*
* @this {CPUStatePDP10}
* @param {number} op
@ -1376,7 +1381,19 @@ PDP10.opASH = function(op, acc)
*/
PDP10.opROT = function(op, acc)
{
this.opUndefined(op);
/*
* Convert the unsigned 18-bit value in regEA to a signed 8-bit value, modulo +/-36.
*/
var s = ((this.regEA << 14) >> 24) % 36;
if (s) {
var w = this.readWord(acc);
if (s > 0) {
w = ((w * Math.pow(2, s)) % PDP10.WORD_LIMIT) + Math.trunc(w / Math.pow(2, 36 - s));
} else {
w = Math.trunc(w / Math.pow(2, -s)) + ((w * Math.pow(2, 36 + s)) % PDP10.WORD_LIMIT);
}
this.writeWord(acc, w);
}
};
/**
@ -1442,7 +1459,14 @@ PDP10.opASHC = function(op, acc)
};
/**
* opROTC(0o245000)
* opROTC(0o245000): Rotate Combined
*
* From the DEC PDP-10 System Reference Manual (May 1968), p. 2-26:
*
* Concatenate accumulators A and A+1 with A on the left, and rotate the 72-bit combination the
* number of places specified by E. If E is positive, rotate left; bit 0 is rotated into bit 71
* (bit 35 of AC A +1) and bit 36 into bit 35. If E is negative, rotate right; bit 35 is rotated
* into bit 36 and bit 71 into bit 0.
*
* @this {CPUStatePDP10}
* @param {number} op
@ -1450,7 +1474,34 @@ PDP10.opASHC = function(op, acc)
*/
PDP10.opROTC = function(op, acc)
{
this.opUndefined(op);
/*
* Convert the unsigned 18-bit value in regEA to a signed 8-bit value.
*/
var s = ((this.regEA << 14) >> 24) % 72;
if (s) {
var wLeft = this.readWord(acc);
var wRight = this.readWord((acc + 1) & 0o17);
var wExcess = wLeft;
if (s > 0) {
if (s < 36) {
wLeft = ((wLeft * Math.pow(2, s)) % PDP10.WORD_LIMIT) + Math.trunc(wRight / Math.pow(2, 36 - s));
wRight = ((wRight * Math.pow(2, s)) % PDP10.WORD_LIMIT) + Math.trunc(wExcess / Math.pow(2, 36 - s));
} else {
wLeft = ((wRight * Math.pow(2, s - 36)) % PDP10.WORD_LIMIT) + Math.trunc(wLeft / Math.pow(2, 72 - s));
wRight = ((wExcess * Math.pow(2, s - 36)) % PDP10.WORD_LIMIT) + Math.trunc(wRight / Math.pow(2, 72 - s));
}
} else {
if (s > -36) {
wLeft = Math.trunc(wLeft / Math.pow(2, -s)) + ((wRight * Math.pow(2, 36 + s)) % PDP10.WORD_LIMIT);
wRight = Math.trunc(wRight / Math.pow(2, -s)) + ((wExcess * Math.pow(2, 36 + s)) % PDP10.WORD_LIMIT);
} else {
wLeft = Math.trunc(wRight / Math.pow(2, -s - 36)) + ((wLeft * Math.pow(2, 72 + s)) % PDP10.WORD_LIMIT);
wRight = Math.trunc(wExcess / Math.pow(2, -s - 36)) + ((wRight * Math.pow(2, 72 + s)) % PDP10.WORD_LIMIT);
}
}
this.writeWord(acc, wLeft);
this.writeWord((acc + 1) & 0o17, wRight);
}
};
/**