X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=include%2Fllvm%2FADT%2FBitVector.h;h=a3a8920186468ebf5f48044752fa0dde6ad4d4bd;hb=fc82fabe00b0b820e3c0d7fc9e289bace0295f11;hp=50ccdab159ead3ea6f0b66cfaee98cd0f3d032fa;hpb=b1183c1ff3b17689c036d5e7443b7343074d2f6f;p=oota-llvm.git

diff --git a/include/llvm/ADT/BitVector.h b/include/llvm/ADT/BitVector.h
index 50ccdab159e..a3a89201864 100644
--- a/include/llvm/ADT/BitVector.h
+++ b/include/llvm/ADT/BitVector.h
@@ -2,8 +2,8 @@
 //
 //                     The LLVM Compiler Infrastructure
 //
-// This file was developed by Evan Cheng and is distributed under
-// the University of Illinois Open Source License. See LICENSE.TXT for details.
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
@@ -16,8 +16,9 @@
 
 #include "llvm/Support/MathExtras.h"
 #include <algorithm>
-#include <cstdlib>
 #include <cassert>
+#include <cstdlib>
+#include <cstring>
 
 namespace llvm {
 
@@ -57,7 +58,7 @@ public:
     }
 
     operator bool() const {
-      return (*WordRef) & (1L << BitPos);
+      return ((*WordRef) & (1L << BitPos)) ? true : false;
     }
   };
 
@@ -245,10 +246,12 @@ public:
 
   // Indexing.
   reference operator[](unsigned Idx) {
+    assert (Idx < Size && "Out-of-bounds Bit access.");
     return reference(*this, Idx);
   }
 
   bool operator[](unsigned Idx) const {
+    assert (Idx < Size && "Out-of-bounds Bit access.");   
     BitWord Mask = 1L << (Idx % BITWORD_SIZE);
     return (Bits[Idx / BITWORD_SIZE] & Mask) != 0;
   }
@@ -259,12 +262,23 @@ public:
 
   // Comparison operators.
   bool operator==(const BitVector &RHS) const {
-    if (Size != RHS.Size)
-      return false;
-
-    for (unsigned i = 0; i < NumBitWords(size()); ++i)
+    unsigned ThisWords = NumBitWords(size());
+    unsigned RHSWords  = NumBitWords(RHS.size());
+    unsigned i;
+    for (i = 0; i != std::min(ThisWords, RHSWords); ++i)
       if (Bits[i] != RHS.Bits[i])
         return false;
+    
+    // Verify that any extra words are all zeros.
+    if (i != ThisWords) {
+      for (; i != ThisWords; ++i)
+        if (Bits[i])
+          return false;
+    } else if (i != RHSWords) {
+      for (; i != RHSWords; ++i)
+        if (RHS.Bits[i])
+          return false;
+    }
     return true;
   }
 
@@ -274,9 +288,18 @@ public:
 
   // Intersection, union, disjoint union.
   BitVector operator&=(const BitVector &RHS) {
-    assert(Size == RHS.Size && "Illegal operation!");
-    for (unsigned i = 0; i < NumBitWords(size()); ++i)
+    unsigned ThisWords = NumBitWords(size());
+    unsigned RHSWords  = NumBitWords(RHS.size());
+    unsigned i;
+    for (i = 0; i != std::min(ThisWords, RHSWords); ++i)
       Bits[i] &= RHS.Bits[i];
+    
+    // Any bits that are just in this bitvector become zero, because they aren't
+    // in the RHS bit vector.  Any words only in RHS are ignored because they
+    // are already zero in the LHS.
+    for (; i != ThisWords; ++i)
+      Bits[i] = 0;
+    
     return *this;
   }
 
@@ -355,6 +378,8 @@ private:
     // Destroy the old bits.
     delete[] Bits;
     Bits = NewBits;
+    
+    clear_unused_bits();
   }
 
   void init_words(BitWord *B, unsigned NumWords, bool t) {