[llvm-commits] CVS: llvm/lib/Support/APInt.cpp

[Reid Spencer]

Changes in directory llvm/lib/Support:

APInt.cpp updated: 1.48 -> 1.49
---
Log message:

Implement the getHashValue method.
Fix toString use of getValue to use getZExtValue()


---
Diffs of the changes:  (+16 -1)

 APInt.cpp |   17 ++++++++++++++++-
 1 files changed, 16 insertions(+), 1 deletion(-)


Index: llvm/lib/Support/APInt.cpp
diff -u llvm/lib/Support/APInt.cpp:1.48 llvm/lib/Support/APInt.cpp:1.49
--- llvm/lib/Support/APInt.cpp:1.48	Mon Feb 26 02:10:54 2007
+++ llvm/lib/Support/APInt.cpp	Mon Feb 26 15:02:27 2007
@@ -661,6 +661,21 @@
   return getMinValue(numBits, false);
 }
 
+uint64_t APInt::getHashValue() const {
+  // LLVM only supports bit widths up to 2^23 so shift the bitwidth into the
+  // high range. This makes the hash unique for integer values < 2^41 bits and
+  // doesn't hurt for larger values.
+  uint64_t hash = uint64_t(BitWidth) << (APINT_BITS_PER_WORD - 23);
+
+  // Add the sum of the words to the hash.
+  if (isSingleWord())
+    hash += VAL;
+  else
+    for (uint32_t i = 0; i < getNumWords(); ++i)
+      hash += pVal[i];
+  return hash;
+}
+
 /// HiBits - This function returns the high "numBits" bits of this APInt.
 APInt APInt::getHiBits(uint32_t numBits) const {
   return APIntOps::lshr(*this, BitWidth - numBits);
@@ -1660,7 +1675,7 @@
     APInt tmp2(tmp.getBitWidth(), 0);
     divide(tmp, tmp.getNumWords(), divisor, divisor.getNumWords(), &tmp2, 
            &APdigit);
-    uint32_t digit = APdigit.getValue();
+    uint32_t digit = APdigit.getZExtValue();
     assert(digit < radix && "divide failed");
     result.insert(insert_at,digits[digit]);
     tmp = tmp2;