ComputeRecursionPoint(originalStart, originalEnd, modifiedStart, modifiedEnd, midOriginalArr, midModifiedArr, quitEarlyArr) {
        let originalIndex = 0, modifiedIndex = 0;
        let diagonalForwardStart = 0, diagonalForwardEnd = 0;
        let diagonalReverseStart = 0, diagonalReverseEnd = 0;
        // To traverse the edit graph and produce the proper LCS, our actual
        // start position is just outside the given boundary
        originalStart--;
        modifiedStart--;
        // We set these up to make the compiler happy, but they will
        // be replaced before we return with the actual recursion point
        midOriginalArr[0] = 0;
        midModifiedArr[0] = 0;
        // Clear out the history
        this.m_forwardHistory = [];
        this.m_reverseHistory = [];
        // Each cell in the two arrays corresponds to a diagonal in the edit graph.
        // The integer value in the cell represents the originalIndex of the furthest
        // reaching point found so far that ends in that diagonal.
        // The modifiedIndex can be computed mathematically from the originalIndex and the diagonal number.
        const maxDifferences = (originalEnd - originalStart) + (modifiedEnd - modifiedStart);
        const numDiagonals = maxDifferences + 1;
        const forwardPoints = new Int32Array(numDiagonals);
        const reversePoints = new Int32Array(numDiagonals);
        // diagonalForwardBase: Index into forwardPoints of the diagonal which passes through (originalStart, modifiedStart)
        // diagonalReverseBase: Index into reversePoints of the diagonal which passes through (originalEnd, modifiedEnd)
        const diagonalForwardBase = (modifiedEnd - modifiedStart);
        const diagonalReverseBase = (originalEnd - originalStart);
        // diagonalForwardOffset: Geometric offset which allows modifiedIndex to be computed from originalIndex and the
        //    diagonal number (relative to diagonalForwardBase)
        // diagonalReverseOffset: Geometric offset which allows modifiedIndex to be computed from originalIndex and the
        //    diagonal number (relative to diagonalReverseBase)
        const diagonalForwardOffset = (originalStart - modifiedStart);
        const diagonalReverseOffset = (originalEnd - modifiedEnd);
        // delta: The difference between the end diagonal and the start diagonal. This is used to relate diagonal numbers
        //   relative to the start diagonal with diagonal numbers relative to the end diagonal.
        // The Even/Oddn-ness of this delta is important for determining when we should check for overlap
        const delta = diagonalReverseBase - diagonalForwardBase;
        const deltaIsEven = (delta % 2 === 0);
        // Here we set up the start and end points as the furthest points found so far
        // in both the forward and reverse directions, respectively
        forwardPoints[diagonalForwardBase] = originalStart;
        reversePoints[diagonalReverseBase] = originalEnd;
        // Remember if we quit early, and thus need to do a best-effort result instead of a real result.
        quitEarlyArr[0] = false;
        // A couple of points:
        // --With this method, we iterate on the number of differences between the two sequences.
        //   The more differences there actually are, the longer this will take.
        // --Also, as the number of differences increases, we have to search on diagonals further
        //   away from the reference diagonal (which is diagonalForwardBase for forward, diagonalReverseBase for reverse).
        // --We extend on even diagonals (relative to the reference diagonal) only when numDifferences
        //   is even and odd diagonals only when numDifferences is odd.
        for (let numDifferences = 1; numDifferences <= (maxDifferences / 2) + 1; numDifferences++) {
            let furthestOriginalIndex = 0;
            let furthestModifiedIndex = 0;
            // Run the algorithm in the forward direction
            diagonalForwardStart = this.ClipDiagonalBound(diagonalForwardBase - numDifferences, numDifferences, diagonalForwardBase, numDiagonals);
            diagonalForwardEnd = this.ClipDiagonalBound(diagonalForwardBase + numDifferences, numDifferences, diagonalForwardBase, numDiagonals);
            for (let diagonal = diagonalForwardStart; diagonal <= diagonalForwardEnd; diagonal += 2) {
                // STEP 1: We extend the furthest reaching point in the present diagonal
                // by looking at the diagonals above and below and picking the one whose point
                // is further away from the start point (originalStart, modifiedStart)
                if (diagonal === diagonalForwardStart || (diagonal < diagonalForwardEnd && forwardPoints[diagonal - 1] < forwardPoints[diagonal + 1])) {
                    originalIndex = forwardPoints[diagonal + 1];
                }
                else {
                    originalIndex = forwardPoints[diagonal - 1] + 1;
                }
                modifiedIndex = originalIndex - (diagonal - diagonalForwardBase) - diagonalForwardOffset;
                // Save the current originalIndex so we can test for false overlap in step 3
                const tempOriginalIndex = originalIndex;
                // STEP 2: We can continue to extend the furthest reaching point in the present diagonal
                // so long as the elements are equal.
                while (originalIndex < originalEnd && modifiedIndex < modifiedEnd && this.ElementsAreEqual(originalIndex + 1, modifiedIndex + 1)) {
                    originalIndex++;
                    modifiedIndex++;
                }
                forwardPoints[diagonal] = originalIndex;
                if (originalIndex + modifiedIndex > furthestOriginalIndex + furthestModifiedIndex) {
                    furthestOriginalIndex = originalIndex;
                    furthestModifiedIndex = modifiedIndex;
                }
                // STEP 3: If delta is odd (overlap first happens on forward when delta is odd)
                // and diagonal is in the range of reverse diagonals computed for numDifferences-1
                // (the previous iteration; we haven't computed reverse diagonals for numDifferences yet)
                // then check for overlap.
                if (!deltaIsEven && Math.abs(diagonal - diagonalReverseBase) <= (numDifferences - 1)) {
                    if (originalIndex >= reversePoints[diagonal]) {
                        midOriginalArr[0] = originalIndex;
                        midModifiedArr[0] = modifiedIndex;
                        if (tempOriginalIndex <= reversePoints[diagonal] && 1447 /* LocalConstants.MaxDifferencesHistory */ > 0 && numDifferences <= (1447 /* LocalConstants.MaxDifferencesHistory */ + 1)) {
                            // BINGO! We overlapped, and we have the full trace in memory!
                            return this.WALKTRACE(diagonalForwardBase, diagonalForwardStart, diagonalForwardEnd, diagonalForwardOffset, diagonalReverseBase, diagonalReverseStart, diagonalReverseEnd, diagonalReverseOffset, forwardPoints, reversePoints, originalIndex, originalEnd, midOriginalArr, modifiedIndex, modifiedEnd, midModifiedArr, deltaIsEven, quitEarlyArr);
                        }
                        else {
                            // Either false overlap, or we didn't have enough memory for the full trace
                            // Just return the recursion point
                            return null;
                        }
                    }
                }
            }
            // Check to see if we should be quitting early, before moving on to the next iteration.
            const matchLengthOfLongest = ((furthestOriginalIndex - originalStart) + (furthestModifiedIndex - modifiedStart) - numDifferences) / 2;
            if (this.ContinueProcessingPredicate !== null && !this.ContinueProcessingPredicate(furthestOriginalIndex, matchLengthOfLongest)) {
                // We can't finish, so skip ahead to generating a result from what we have.
                quitEarlyArr[0] = true;
                // Use the furthest distance we got in the forward direction.
                midOriginalArr[0] = furthestOriginalIndex;
                midModifiedArr[0] = furthestModifiedIndex;
                if (matchLengthOfLongest > 0 && 1447 /* LocalConstants.MaxDifferencesHistory */ > 0 && numDifferences <= (1447 /* LocalConstants.MaxDifferencesHistory */ + 1)) {
                    // Enough of the history is in memory to walk it backwards
                    return this.WALKTRACE(diagonalForwardBase, diagonalForwardStart, diagonalForwardEnd, diagonalForwardOffset, diagonalReverseBase, diagonalReverseStart, diagonalReverseEnd, diagonalReverseOffset, forwardPoints, reversePoints, originalIndex, originalEnd, midOriginalArr, modifiedIndex, modifiedEnd, midModifiedArr, deltaIsEven, quitEarlyArr);
                }
                else {
                    // We didn't actually remember enough of the history.
                    //Since we are quitting the diff early, we need to shift back the originalStart and modified start
                    //back into the boundary limits since we decremented their value above beyond the boundary limit.
                    originalStart++;
                    modifiedStart++;
                    return [
                        new DiffChange(originalStart, originalEnd - originalStart + 1, modifiedStart, modifiedEnd - modifiedStart + 1)
                    ];
                }
            }
            // Run the algorithm in the reverse direction
            diagonalReverseStart = this.ClipDiagonalBound(diagonalReverseBase - numDifferences, numDifferences, diagonalReverseBase, numDiagonals);
            diagonalReverseEnd = this.ClipDiagonalBound(diagonalReverseBase + numDifferences, numDifferences, diagonalReverseBase, numDiagonals);
            for (let diagonal = diagonalReverseStart; diagonal <= diagonalReverseEnd; diagonal += 2) {
                // STEP 1: We extend the furthest reaching point in the present diagonal
                // by looking at the diagonals above and below and picking the one whose point
                // is further away from the start point (originalEnd, modifiedEnd)
                if (diagonal === diagonalReverseStart || (diagonal < diagonalReverseEnd && reversePoints[diagonal - 1] >= reversePoints[diagonal + 1])) {
                    originalIndex = reversePoints[diagonal + 1] - 1;
                }
                else {
                    originalIndex = reversePoints[diagonal - 1];
                }
                modifiedIndex = originalIndex - (diagonal - diagonalReverseBase) - diagonalReverseOffset;
                // Save the current originalIndex so we can test for false overlap
                const tempOriginalIndex = originalIndex;
                // STEP 2: We can continue to extend the furthest reaching point in the present diagonal
                // as long as the elements are equal.
                while (originalIndex > originalStart && modifiedIndex > modifiedStart && this.ElementsAreEqual(originalIndex, modifiedIndex)) {
                    originalIndex--;
                    modifiedIndex--;
                }
                reversePoints[diagonal] = originalIndex;
                // STEP 4: If delta is even (overlap first happens on reverse when delta is even)
                // and diagonal is in the range of forward diagonals computed for numDifferences
                // then check for overlap.
                if (deltaIsEven && Math.abs(diagonal - diagonalForwardBase) <= numDifferences) {
                    if (originalIndex <= forwardPoints[diagonal]) {
                        midOriginalArr[0] = originalIndex;
                        midModifiedArr[0] = modifiedIndex;
                        if (tempOriginalIndex >= forwardPoints[diagonal] && 1447 /* LocalConstants.MaxDifferencesHistory */ > 0 && numDifferences <= (1447 /* LocalConstants.MaxDifferencesHistory */ + 1)) {
                            // BINGO! We overlapped, and we have the full trace in memory!
                            return this.WALKTRACE(diagonalForwardBase, diagonalForwardStart, diagonalForwardEnd, diagonalForwardOffset, diagonalReverseBase, diagonalReverseStart, diagonalReverseEnd, diagonalReverseOffset, forwardPoints, reversePoints, originalIndex, originalEnd, midOriginalArr, modifiedIndex, modifiedEnd, midModifiedArr, deltaIsEven, quitEarlyArr);
                        }
                        else {
                            // Either false overlap, or we didn't have enough memory for the full trace
                            // Just return the recursion point
                            return null;
                        }
                    }
                }
            }
            // Save current vectors to history before the next iteration
            if (numDifferences <= 1447 /* LocalConstants.MaxDifferencesHistory */) {
                // We are allocating space for one extra int, which we fill with
                // the index of the diagonal base index
                let temp = new Int32Array(diagonalForwardEnd - diagonalForwardStart + 2);
                temp[0] = diagonalForwardBase - diagonalForwardStart + 1;
                MyArray.Copy2(forwardPoints, diagonalForwardStart, temp, 1, diagonalForwardEnd - diagonalForwardStart + 1);
                this.m_forwardHistory.push(temp);
                temp = new Int32Array(diagonalReverseEnd - diagonalReverseStart + 2);
                temp[0] = diagonalReverseBase - diagonalReverseStart + 1;
                MyArray.Copy2(reversePoints, diagonalReverseStart, temp, 1, diagonalReverseEnd - diagonalReverseStart + 1);
                this.m_reverseHistory.push(temp);
            }
        }
        // If we got here, then we have the full trace in history. We just have to convert it to a change list
        // NOTE: This part is a bit messy
        return this.WALKTRACE(diagonalForwardBase, diagonalForwardStart, diagonalForwardEnd, diagonalForwardOffset, diagonalReverseBase, diagonalReverseStart, diagonalReverseEnd, diagonalReverseOffset, forwardPoints, reversePoints, originalIndex, originalEnd, midOriginalArr, modifiedIndex, modifiedEnd, midModifiedArr, deltaIsEven, quitEarlyArr);
    }
Given the range to compute the diff on, this method finds the point:
(midOriginal, midModified)
that exists in the middle of the LCS of the two sequences and
is the point at which the LCS problem may be broken down recursively.
This method will try to keep the LCS trace in memory. If the LCS recursion
point is calculated and the full trace is available in memory, then this method
will return the change list.
@param originalStart The start bound of the original sequence range
@param originalEnd The end bound of the original sequence range
@param modifiedStart The start bound of the modified sequence range
@param modifiedEnd The end bound of the modified sequence range
@param midOriginal The middle point of the original sequence range
@param midModified The middle point of the modified sequence range
@returns The diff changes, if available, otherwise null