1.1 --- a/src/share/classes/com/sun/tools/javac/util/Bits.java Sat Sep 14 15:23:21 2013 +0100
1.2 +++ b/src/share/classes/com/sun/tools/javac/util/Bits.java Sat Sep 14 19:04:47 2013 +0100
1.3 @@ -27,8 +27,6 @@
1.4
1.5 import java.util.Arrays;
1.6
1.7 -import static com.sun.tools.javac.util.Bits.BitsOpKind.*;
1.8 -
1.9 /** A class for extensible, mutable bit sets.
1.10 *
1.11 * <p><b>This is NOT part of any supported API.
1.12 @@ -38,20 +36,6 @@
1.13 */
1.14 public class Bits {
1.15
1.16 - public enum BitsOpKind {
1.17 - INIT,
1.18 - CLEAR,
1.19 - INCL_BIT,
1.20 - EXCL_BIT,
1.21 - ASSIGN,
1.22 - AND_SET,
1.23 - OR_SET,
1.24 - DIFF_SET,
1.25 - XOR_SET,
1.26 - INCL_RANGE,
1.27 - EXCL_RANGE,
1.28 - }
1.29 -
1.30 // ____________ reset _________
1.31 // / UNKNOWN \ <-------- / UNINIT \
1.32 // \____________/ | \_________/
1.33 @@ -64,11 +48,14 @@
1.34 // | |
1.35 // -----------
1.36 // any
1.37 - private enum BitsState {
1.38 + protected enum BitsState {
1.39 /* A Bits instance is in UNKNOWN state if it has been explicitly reset.
1.40 * It is possible to get to this state from any other by calling the
1.41 * reset method. An instance in the UNKNOWN state can pass to the
1.42 * NORMAL state after being assigned another Bits instance.
1.43 + *
1.44 + * Bits instances are final fields in Flow so the UNKNOWN state models
1.45 + * the null assignment.
1.46 */
1.47 UNKNOWN,
1.48 /* A Bits instance is in UNINIT when it is created with the default
1.49 @@ -103,13 +90,9 @@
1.50
1.51 public int[] bits = null;
1.52 // This field will store last version of bits after every change.
1.53 - public int[] oldBits = null;
1.54 -
1.55 - public BitsOpKind lastOperation = null;
1.56 -
1.57 private static final int[] unassignedBits = new int[0];
1.58
1.59 - private BitsState currentState;
1.60 + protected BitsState currentState;
1.61
1.62 /** Construct an initially empty set.
1.63 */
1.64 @@ -127,27 +110,20 @@
1.65
1.66 /** Construct a set consisting initially of given bit vector.
1.67 */
1.68 - private Bits(int[] bits, BitsState initState) {
1.69 + protected Bits(int[] bits, BitsState initState) {
1.70 this.bits = bits;
1.71 this.currentState = initState;
1.72 switch (initState) {
1.73 case UNKNOWN:
1.74 - reset(); //this will also set current state;
1.75 + this.bits = null;
1.76 break;
1.77 case NORMAL:
1.78 Assert.check(bits != unassignedBits);
1.79 - lastOperation = INIT;
1.80 break;
1.81 }
1.82 }
1.83
1.84 - /** This method will be called after any operation that causes a change to
1.85 - * the bits. Subclasses can thus override it in order to extract information
1.86 - * from the changes produced to the bits by the given operation.
1.87 - */
1.88 - public void changed() {}
1.89 -
1.90 - private void sizeTo(int len) {
1.91 + protected void sizeTo(int len) {
1.92 if (bits.length < len) {
1.93 bits = Arrays.copyOf(bits, len);
1.94 }
1.95 @@ -157,16 +133,18 @@
1.96 */
1.97 public void clear() {
1.98 Assert.check(currentState != BitsState.UNKNOWN);
1.99 - oldBits = bits;
1.100 - lastOperation = CLEAR;
1.101 - for (int i = 0; i < bits.length; i++) bits[i] = 0;
1.102 - changed();
1.103 + for (int i = 0; i < bits.length; i++) {
1.104 + bits[i] = 0;
1.105 + }
1.106 currentState = BitsState.NORMAL;
1.107 }
1.108
1.109 public void reset() {
1.110 + internalReset();
1.111 + }
1.112 +
1.113 + protected void internalReset() {
1.114 bits = null;
1.115 - oldBits = null;
1.116 currentState = BitsState.UNKNOWN;
1.117 }
1.118
1.119 @@ -175,40 +153,40 @@
1.120 }
1.121
1.122 public Bits assign(Bits someBits) {
1.123 - lastOperation = ASSIGN;
1.124 - oldBits = bits;
1.125 bits = someBits.dup().bits;
1.126 - changed();
1.127 currentState = BitsState.NORMAL;
1.128 return this;
1.129 }
1.130
1.131 /** Return a copy of this set.
1.132 */
1.133 - private Bits dup() {
1.134 + public Bits dup() {
1.135 Assert.check(currentState != BitsState.UNKNOWN);
1.136 Bits tmp = new Bits();
1.137 - if (currentState != BitsState.NORMAL) {
1.138 - tmp.bits = bits;
1.139 - } else {
1.140 - tmp.bits = new int[bits.length];
1.141 - System.arraycopy(bits, 0, tmp.bits, 0, bits.length);
1.142 - }
1.143 + tmp.bits = dupBits();
1.144 currentState = BitsState.NORMAL;
1.145 return tmp;
1.146 }
1.147
1.148 + protected int[] dupBits() {
1.149 + int [] result;
1.150 + if (currentState != BitsState.NORMAL) {
1.151 + result = bits;
1.152 + } else {
1.153 + result = new int[bits.length];
1.154 + System.arraycopy(bits, 0, result, 0, bits.length);
1.155 + }
1.156 + return result;
1.157 + }
1.158 +
1.159 /** Include x in this set.
1.160 */
1.161 public void incl(int x) {
1.162 Assert.check(currentState != BitsState.UNKNOWN);
1.163 - Assert.check(x >= 0);
1.164 - oldBits = bits;
1.165 - lastOperation = INCL_BIT;
1.166 + Assert.check(x >= 0, "Value of x " + x);
1.167 sizeTo((x >>> wordshift) + 1);
1.168 bits[x >>> wordshift] = bits[x >>> wordshift] |
1.169 (1 << (x & wordmask));
1.170 - changed();
1.171 currentState = BitsState.NORMAL;
1.172 }
1.173
1.174 @@ -217,14 +195,11 @@
1.175 */
1.176 public void inclRange(int start, int limit) {
1.177 Assert.check(currentState != BitsState.UNKNOWN);
1.178 - oldBits = bits;
1.179 - lastOperation = INCL_RANGE;
1.180 sizeTo((limit >>> wordshift) + 1);
1.181 for (int x = start; x < limit; x++) {
1.182 bits[x >>> wordshift] = bits[x >>> wordshift] |
1.183 (1 << (x & wordmask));
1.184 }
1.185 - changed();
1.186 currentState = BitsState.NORMAL;
1.187 }
1.188
1.189 @@ -232,13 +207,10 @@
1.190 */
1.191 public void excludeFrom(int start) {
1.192 Assert.check(currentState != BitsState.UNKNOWN);
1.193 - oldBits = bits;
1.194 - lastOperation = EXCL_RANGE;
1.195 Bits temp = new Bits();
1.196 temp.sizeTo(bits.length);
1.197 temp.inclRange(0, start);
1.198 internalAndSet(temp);
1.199 - changed();
1.200 currentState = BitsState.NORMAL;
1.201 }
1.202
1.203 @@ -247,12 +219,9 @@
1.204 public void excl(int x) {
1.205 Assert.check(currentState != BitsState.UNKNOWN);
1.206 Assert.check(x >= 0);
1.207 - oldBits = bits;
1.208 - lastOperation = EXCL_BIT;
1.209 sizeTo((x >>> wordshift) + 1);
1.210 bits[x >>> wordshift] = bits[x >>> wordshift] &
1.211 ~(1 << (x & wordmask));
1.212 - changed();
1.213 currentState = BitsState.NORMAL;
1.214 }
1.215
1.216 @@ -269,15 +238,12 @@
1.217 */
1.218 public Bits andSet(Bits xs) {
1.219 Assert.check(currentState != BitsState.UNKNOWN);
1.220 - oldBits = bits;
1.221 - lastOperation = AND_SET;
1.222 internalAndSet(xs);
1.223 - changed();
1.224 currentState = BitsState.NORMAL;
1.225 return this;
1.226 }
1.227
1.228 - private void internalAndSet(Bits xs) {
1.229 + protected void internalAndSet(Bits xs) {
1.230 Assert.check(currentState != BitsState.UNKNOWN);
1.231 sizeTo(xs.bits.length);
1.232 for (int i = 0; i < xs.bits.length; i++) {
1.233 @@ -289,13 +255,10 @@
1.234 */
1.235 public Bits orSet(Bits xs) {
1.236 Assert.check(currentState != BitsState.UNKNOWN);
1.237 - oldBits = bits;
1.238 - lastOperation = OR_SET;
1.239 sizeTo(xs.bits.length);
1.240 for (int i = 0; i < xs.bits.length; i++) {
1.241 bits[i] = bits[i] | xs.bits[i];
1.242 }
1.243 - changed();
1.244 currentState = BitsState.NORMAL;
1.245 return this;
1.246 }
1.247 @@ -304,14 +267,11 @@
1.248 */
1.249 public Bits diffSet(Bits xs) {
1.250 Assert.check(currentState != BitsState.UNKNOWN);
1.251 - oldBits = bits;
1.252 - lastOperation = DIFF_SET;
1.253 for (int i = 0; i < bits.length; i++) {
1.254 if (i < xs.bits.length) {
1.255 bits[i] = bits[i] & ~xs.bits[i];
1.256 }
1.257 }
1.258 - changed();
1.259 currentState = BitsState.NORMAL;
1.260 return this;
1.261 }
1.262 @@ -320,13 +280,10 @@
1.263 */
1.264 public Bits xorSet(Bits xs) {
1.265 Assert.check(currentState != BitsState.UNKNOWN);
1.266 - oldBits = bits;
1.267 - lastOperation = XOR_SET;
1.268 sizeTo(xs.bits.length);
1.269 for (int i = 0; i < xs.bits.length; i++) {
1.270 bits[i] = bits[i] ^ xs.bits[i];
1.271 }
1.272 - changed();
1.273 currentState = BitsState.NORMAL;
1.274 return this;
1.275 }
1.276 @@ -336,7 +293,9 @@
1.277 */
1.278 private static int trailingZeroBits(int x) {
1.279 Assert.check(wordlen == 32);
1.280 - if (x == 0) return 32;
1.281 + if (x == 0) {
1.282 + return 32;
1.283 + }
1.284 int n = 1;
1.285 if ((x & 0xffff) == 0) { n += 16; x >>>= 16; }
1.286 if ((x & 0x00ff) == 0) { n += 8; x >>>= 8; }
1.287 @@ -355,24 +314,31 @@
1.288 public int nextBit(int x) {
1.289 Assert.check(currentState != BitsState.UNKNOWN);
1.290 int windex = x >>> wordshift;
1.291 - if (windex >= bits.length) return -1;
1.292 + if (windex >= bits.length) {
1.293 + return -1;
1.294 + }
1.295 int word = bits[windex] & ~((1 << (x & wordmask))-1);
1.296 while (true) {
1.297 - if (word != 0)
1.298 + if (word != 0) {
1.299 return (windex << wordshift) + trailingZeroBits(word);
1.300 + }
1.301 windex++;
1.302 - if (windex >= bits.length) return -1;
1.303 + if (windex >= bits.length) {
1.304 + return -1;
1.305 + }
1.306 word = bits[windex];
1.307 }
1.308 }
1.309
1.310 /** a string representation of this set.
1.311 */
1.312 + @Override
1.313 public String toString() {
1.314 - if (bits.length > 0) {
1.315 + if (bits != null && bits.length > 0) {
1.316 char[] digits = new char[bits.length * wordlen];
1.317 - for (int i = 0; i < bits.length * wordlen; i++)
1.318 + for (int i = 0; i < bits.length * wordlen; i++) {
1.319 digits[i] = isMember(i) ? '1' : '0';
1.320 + }
1.321 return new String(digits);
1.322 } else {
1.323 return "[]";
1.324 @@ -396,6 +362,8 @@
1.325 System.out.println("found " + i);
1.326 count ++;
1.327 }
1.328 - if (count != 125) throw new Error();
1.329 + if (count != 125) {
1.330 + throw new Error();
1.331 + }
1.332 }
1.333 }
