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Fixed the Debugger's arithmetic truncation function (truncate())

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This commit is contained in:
Jeff 2017-04-01 14:36:39 -07:00 • committed by Jeff Parsons
commit 75b9a9c2ba
9 changed files with 84 additions and 149 deletions
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22
modules/shared/lib/debugger.js
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@ -473,15 +473,21 @@ class Debugger extends Component
}
else {
if (nBits <= 32) {
vNew = v | 0;
} else {
vNew = (v << (32 - nBits)) >> (32 - nBits);
}
else {
limit = Math.pow(2, nBits - 1);
if (v < -limit) {
if (v < -limit * 2) vNew = v % (limit * 2);
vNew += (limit * 2);
} else if (vNew >= limit) {
if (v >= limit * 2) vNew = v % (limit * 2);
vNew -= (limit * 2); // the sign bit was set in this overly large value, so make it negative
if (v >= limit) {
vNew = (v % limit);
if (((v / limit)|0) & 1) vNew -= limit;
} else if (v < -limit) {
vNew = (v % limit);
if ((((-v - 1) / limit) | 0) & 1) {
if (vNew) vNew += limit;
}
else {
if (!vNew) vNew -= limit;
}
}
}
}