[llvm-commits] CVS: llvm/lib/VMCore/Constants.cpp

[Evan Cheng]

Changes in directory llvm/lib/VMCore:

Constants.cpp updated: 1.167 -> 1.168
---
Log message:

Speed up isCString()

---
Diffs of the changes:  (+14 -4)

 Constants.cpp |   18 ++++++++++++++----
 1 files changed, 14 insertions(+), 4 deletions(-)


Index: llvm/lib/VMCore/Constants.cpp
diff -u llvm/lib/VMCore/Constants.cpp:1.167 llvm/lib/VMCore/Constants.cpp:1.168
--- llvm/lib/VMCore/Constants.cpp:1.167	Thu Oct 26 14:15:05 2006
+++ llvm/lib/VMCore/Constants.cpp	Thu Oct 26 16:48:03 2006
@@ -1077,11 +1077,21 @@
 /// isString) and it ends in a null byte \0 and does not contains any other
 /// null bytes except its terminator.
 bool ConstantArray::isCString() const {
-  if (!isString()) return false;
-  // This is safe because a ConstantArray cannot be a zero array.
-  for (unsigned i = 0, e = getNumOperands()-1; i != e; ++i)
-    if (cast<ConstantInt>(getOperand(i))->getZExtValue() == 0)
+  // Check the element type for sbyte or ubyte...
+  if (getType()->getElementType() != Type::UByteTy &&
+      getType()->getElementType() != Type::SByteTy)
+    return false;
+  Constant *Zero = Constant::getNullValue(getOperand(0)->getType());
+  // Last element must be a null.
+  if (getOperand(getNumOperands()-1) != Zero)
+    return false;
+  // Other elements must be non-null integers.
+  for (unsigned i = 0, e = getNumOperands()-1; i != e; ++i) {
+    if (!isa<ConstantInt>(getOperand(i)))
       return false;
+    if (getOperand(i) == Zero)
+      return false;
+  }
   return true;
 }