upload datalab

labs/datalab/bits.c

@@ -143,7 +143,7 @@ NOTES:
  *   Rating: 1
  */
 int bitXor(int x, int y) {
-  return 2;
+  return ~(~(x & ~y) & ~(~x & y));
 }
 /* 
  * tmin - return minimum two's complement integer 
@@ -152,9 +152,7 @@ int bitXor(int x, int y) {
  *   Rating: 1
  */
 int tmin(void) {
-
-  return 2;
-
+  return 1 << 31;
 }
 //2
 /*
@@ -165,7 +163,7 @@ int tmin(void) {
  *   Rating: 1
  */
 int isTmax(int x) {
-  return 2;
+  return !((x + 1) ^ ~x) & !!(x + 1);
 }
 /* 
  * allOddBits - return 1 if all odd-numbered bits in word set to 1
@@ -176,7 +174,11 @@ int isTmax(int x) {
  *   Rating: 2
  */
 int allOddBits(int x) {
-  return 2;
+  x = x & (x >> 16);
+  x = x & (x >> 8);
+  x = x & (x >> 4);
+  x = x & (x >> 2);
+  return (x >> 1) & 0x01;
 }
 /* 
  * negate - return -x 
@@ -186,7 +188,7 @@ int allOddBits(int x) {
  *   Rating: 2
  */
 int negate(int x) {
-  return 2;
+  return ~x + 1;
 }
 //3
 /* 
@@ -199,7 +201,8 @@ int negate(int x) {
  *   Rating: 3
  */
 int isAsciiDigit(int x) {
-  return 2;
+  x = x ^ 0x30;
+  return (!(x >> 4)) & ((~x >> 3) | ((~x >> 2) & (~x >> 1)));
 }
 /* 
  * conditional - same as x ? y : z 
@@ -209,7 +212,9 @@ int isAsciiDigit(int x) {
  *   Rating: 3
  */
 int conditional(int x, int y, int z) {
-  return 2;
+  x = !!x;
+  x = (x << 31) >> 31;
+  return (x & y) | (~x & z);
 }
 /* 
  * isLessOrEqual - if x <= y  then return 1, else return 0 
@@ -219,7 +224,9 @@ int conditional(int x, int y, int z) {
  *   Rating: 3
  */
 int isLessOrEqual(int x, int y) {
-  return 2;
+  int x_neg = x >> 31, y_neg = y >> 31;
+  y = y + ~x + 1;
+  return ((x_neg & ~y_neg) | ~((~x_neg & y_neg) | (y >> 31))) & 1;
 }
 //4
 /* 
@@ -231,7 +238,12 @@ int isLessOrEqual(int x, int y) {
  *   Rating: 4 
  */
 int logicalNeg(int x) {
-  return 2;
+  x = x | (x >> 16);
+  x = x | (x >> 8);
+  x = x | (x >> 4);
+  x = x | (x >> 2);
+  x = x | (x >> 1);
+  return ~x & 1;
 }
 /* howManyBits - return the minimum number of bits required to represent x in
  *             two's complement
@@ -246,7 +258,26 @@ int logicalNeg(int x) {
  *  Rating: 4
  */
 int howManyBits(int x) {
-  return 0;
+  int cnt = 1, a;
+  x = x ^ (x >> 31);
+
+  a = !!(x >> 16) << 4;
+  x = x >> a;
+  cnt = cnt + a;
+
+  a = !!(x >> 8) << 3;
+  x = x >> a;
+  cnt = cnt + a;
+
+  a = !!(x >> 4) << 2;
+  x = x >> a;
+  cnt = cnt + a;
+
+  a = !!(x >> 2) << 1;
+  x = x >> a;
+  cnt = cnt + a;
+
+  return cnt + !!x + !!(x >> 1);
 }
 //float
 /* 
@@ -261,7 +292,27 @@ int howManyBits(int x) {
  *   Rating: 4
  */
 unsigned floatScale2(unsigned uf) {
-  return 2;
+  unsigned s = uf & 0x80000000, f = uf & 0x007FFFFF, e = (uf >> 23) & 0xFF;
+
+  if (e == 0xFFU) {
+    return uf;
+  }
+
+  if (e == 0U) {
+    if (f == 0U) {
+      return uf;
+    } else {
+      e = (f >= 0x00400000U);
+      f = (f << 1) & 0x007FFFFFU;
+      return s | (e << 23) | f;
+    }
+  }
+  
+  e = e + 1;
+  if (e == 0xFFU) {
+    f = 0;
+  }
+  return s | (e << 23) | f;
 }
 /* 
  * floatFloat2Int - Return bit-level equivalent of expression (int) f
@@ -276,7 +327,31 @@ unsigned floatScale2(unsigned uf) {
  *   Rating: 4
  */
 int floatFloat2Int(unsigned uf) {
-  return 2;
+  unsigned s = uf & 0x80000000, f = uf & 0x007FFFFF, e = (uf >> 23) & 0xFF;
+  
+  if (e == 0xFFU) {
+    return 0x80000000U;
+  }
+
+  if (e == 0U) {
+    return 0;
+  } else {
+    int E = e - 127;
+    
+    if (E <= -1) {
+      return 0;
+    } else if (E <= 30) {
+      f = (f | 0x00800000);
+      if (E >= 23) {
+        f = f << (E - 23);
+      } else {
+        f = f >> (23 - E);
+      }
+      return s ? -f : f;
+    } else {
+      return 0x80000000U;
+    }
+  }
 }
 /* 
  * floatPower2 - Return bit-level equivalent of the expression 2.0^x
@@ -292,5 +367,13 @@ int floatFloat2Int(unsigned uf) {
  *   Rating: 4
  */
 unsigned floatPower2(int x) {
-    return 2;
+  if (x < -149) {
+    return 0U;
+  } else if (x <= -127) {
+    return 1U << (x + 149);
+  } else if (x <= 127) {
+    return (x + 127) << 23;
+  } else {
+    return 0x7F800000U;
+  }
 }