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Updated the extended logical operations (LSHC and ROTC) to treat the result as a 71-bit result, and ASHC to treat it as a 70-bit result

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Jeff 2017-03-06 16:42:29 -08:00 • committed by Jeff Parsons
commit 04ae721eb6
1 changed files with 16 additions and 0 deletions
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16
modules/shared/lib/int36.js
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@ -694,6 +694,7 @@ class Int36 {
{
num = Int36.validate(num);
this.error = Int36.ERROR.NONE;
/*
* Convert the unsigned 18-bit value in regEA to a signed 8-bit value (+/-255).
*/
@ -757,6 +758,10 @@ class Int36 {
else {
/*
* Simulate opASHC()
*
* TODO: Note that we force the result to be treated as a 70-bit result (we set magnitude to 70 at the end);
* however, what should happen if the incoming value wasn't a proper 70-bit value (ie, if the signs of value
* and extended didn't match)?
*/
var bits;
var wRight = this.value;
@ -879,6 +884,7 @@ class Int36 {
}
this.value = wRight;
this.extended = wLeft;
this.magnitude = 70;
}
}
}
@ -955,6 +961,11 @@ class Int36 {
}
this.value = wRight;
this.extended = wLeft;
/*
* TODO: Perhaps we should support magnitude 72 as way of indicating that the value should always be
* treated as an unsigned 72-bit value?
*/
this.magnitude = 71;
}
}
}
@ -1019,6 +1030,11 @@ class Int36 {
}
this.value = wRight;
this.extended = wLeft;
/*
* TODO: Perhaps we should support magnitude 72 as way of indicating that the value should always be
* treated as an unsigned 72-bit value?
*/
this.magnitude = 71;
}
}
}