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return;
                  }
                  stack.length = newStackLength;
                } else if (
                  funcId in ttContext.functionsDefined &&
                  !functionsCalled.includes(funcId)
                ) {
                  callstack.push({ data, i, stackTop: stack.length - 1 });
                  functionsCalled.push(funcId);
                  pc = ttContext.functionsDefined[funcId];
                  if (!pc) {
                    warn("TT: CALL non-existent function");
                    ttContext.hintsValid = false;
                    return;
                  }
                  data = pc.data;
                  i = pc.i;
                }
              }
            }
          } else if (op === 0x2c && !tooComplexToFollowFunctions) {
            
            if (inFDEF || inELSE) {
              warn("TT: nested FDEFs not allowed");
              tooComplexToFollowFunctions = true;
            }
            inFDEF = true;
            
            lastDeff = i;
            funcId = stack.pop();