5091921: Sign flip issues in loop optimizer
Summary: Fix integer overflow problem in the code generated by loop optimizer.
Reviewed-by: never
/*
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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*
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
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*/
/**
* @test
* @bug 6890943
* @summary JVM mysteriously gives wrong result on 64-bit 1.6 VMs in hotspot mode.
*
* @run shell Test6890943.sh
*/
import java.util.*;
import java.io.*;
import java.util.regex.*;
public class Test6890943 {
public static final boolean AIR = true, ROCK = false;
public static void main(String[] args) {
new Test6890943().go();
}
int r, c, f, t;
boolean[][] grid;
public void go() {
Scanner s = new Scanner(System.in);
s.useDelimiter("\\s+");
int T = s.nextInt();
for (t = 0 ; t < T ; t++) {
r = s.nextInt(); c = s.nextInt(); f = s.nextInt();
grid = new boolean[r][c];
for (int x = 0 ; x < r ; x++) {
String line = s.next();
for (int y = 0 ; y < c ; y++) grid[x][y] = line.charAt(y) == '.';
}
int digs = solve();
String res = digs == -1 ? "No" : "Yes " + digs;
System.out.printf("Case #%d: %s\n", t+1, res);
}
}
Map<Integer, Integer> M = new HashMap<Integer, Integer>();
private int solve() {
M = new HashMap<Integer, Integer>();
M.put(calcWalkingRange(0, 0), 0);
for (int digDown = 0 ; digDown < r ; digDown++) {
Map<Integer, Integer> tries = new HashMap<Integer, Integer>();
for (Map.Entry<Integer, Integer> m : M.entrySet()) {
int q = m.getKey();
if (depth(q) != (digDown)) continue;
if (stuck(q)) continue;
tries.put(q, m.getValue());
}
for (Map.Entry<Integer, Integer> m : tries.entrySet()) {
int q = m.getKey();
int fallLeftDelta = 0, fallRightDelta = 0;
//fall left
int fallLeft = fall(digDown, start(q));
if (fallLeft > 0) {
fallLeftDelta = 1;
if (fallLeft <= f) addToM(calcWalkingRange(digDown+fallLeft, start(q)), m.getValue());
}
//fall right
int fallRight = fall(digDown, end(q));
if (fallRight > 0) {
fallRightDelta = 1;
if (fallRight <= f) addToM(calcWalkingRange(digDown+fallRight, end(q)), m.getValue());
}
for (int p = start(q) + fallLeftDelta ; p <= end(q) - fallRightDelta ; p++) {
//goLeft
for (int digSpot = p ; digSpot > start(q) +fallLeftDelta ; digSpot--) {
int fallDown = 1+fall(digDown+1, digSpot);
if (fallDown <= f) {
if (fallDown == 1) {
addToM(calcWalkingRange(digDown + 1, digSpot, digSpot, p), m.getValue() + Math.abs(digSpot-p)+1);
} else {
addToM(calcWalkingRange(digDown + fallDown, digSpot), m.getValue() + Math.abs(digSpot-p)+1);
}
}
}
//goRight
for (int digSpot = p ; digSpot < end(q)-fallRightDelta ;digSpot++) {
int fallDown = 1+fall(digDown+1, digSpot);
if (fallDown <= f) {
if (fallDown == 1) {
addToM(calcWalkingRange(digDown + 1, digSpot, p, digSpot), m.getValue() + Math.abs(digSpot-p)+1);
} else {
addToM(calcWalkingRange(digDown + fallDown, digSpot), m.getValue() + Math.abs(digSpot-p)+1);
}
}
}
}
}
}
int result = Integer.MAX_VALUE;
for (Map.Entry<Integer, Integer> m : M.entrySet()) {
if (depth(m.getKey()) == r-1) result = Math.min(m.getValue(), result);
}
if (result == Integer.MAX_VALUE) return -1;
return result;
}
private void addToM(int q, int i) {
Integer original = M.get(q);
if ( original == null ) M.put(q, i);
else M.put(q, Math.min(original, i));
}
private int fall(int row, int column) {
int res = 0;
for ( int p = row+1 ; p < r ; p++) {
if (grid[p][column] == AIR) res++;
else break;
}
return res;
}
private boolean stuck(int q) {
return start(q) == end(q);
}
private int depth(int q) {
return q % 50;
}
private int start(int q) {
return q / (50*50);
}
private int end(int q) {
return (q / 50) % 50;
}
private int calcWalkingRange(int depth, int pos) {
return calcWalkingRange(depth, pos, Integer.MAX_VALUE, Integer.MIN_VALUE);
}
private int calcWalkingRange(int depth, int pos, int airOverrideStart, int airOverrideEnd) {
int left = pos, right = pos;
if (depth >= r) return (c-1)*50 + depth;
while (left > 0) {
if (grid[depth][left-1] == ROCK && (left-1 < airOverrideStart || left-1 > airOverrideEnd)) break;
if (depth < r-1 && grid[depth+1][left-1] == AIR) {
left--;
break;
}
left--;
}
while (right < c-1) {
if (grid[depth][right+1] == ROCK && (right+1 < airOverrideStart || right+1 > airOverrideEnd)) break;
if (depth < r-1 && grid[depth+1][right+1] == AIR) {
right++;
break;
}
right++;
}
return left *50*50 + right*50 + depth;
}
}