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Fixed OPDEF opcode generation (improper use of bitwise operators)

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This commit is contained in:
Jeff 2017-04-04 11:26:49 -07:00 • committed by Jeff Parsons
commit 427e6afdb8
3 changed files with 112 additions and 100 deletions
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7
modules/pdp10/lib/macro10.js
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@ -815,7 +815,12 @@ class Macro10 {
this.popScope();
if (w !== undefined) {
this.aWords[nLocation] += (w & (PDP10.OPCODE.A_FIELD | PDP10.OPCODE.X_FIELD | PDP10.OPCODE.Y_FIELD));
this.aWords[nLocation] |= (w & PDP10.OPCODE.I_FIELD);
/*
* We can't "OR" (|=) the I_FIELD bit into the target word, because it's a 36-bit value and bitwise
* operators truncate to 32 bits, so we'll use addition, trusting that the field was initially zero.
*/
this.dbg.assert(!(this.aWords[nLocation] & PDP10.OPCODE.I_FIELD));
this.aWords[nLocation] += (w & PDP10.OPCODE.I_FIELD);
if (sFixup) {
if (!this.aFixups[nLocation]) {
this.aFixups[nLocation] = sFixup;