reapply the patches reverted in r149470 that reenable ConstantDataArray,

but with a critical fix to the SelectionDAG code that optimizes copies
from strings into immediate stores: the previous code was stopping reading
string data at the first nul.  Address this by adding a new argument to
llvm::getConstantStringInfo, preserving the behavior before the patch.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@149800 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 9 insertions, 47 deletions

diff --git a/include/llvm/Analysis/ValueTracking.h b/include/llvm/Analysis/ValueTracking.h
index 300f51df37..dfd774b916 100644
--- a/include/llvm/Analysis/ValueTracking.h
+++ b/include/llvm/Analysis/ValueTracking.h
@@ -17,14 +17,13 @@
 
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/Support/DataTypes.h"
-#include <string>
 
 namespace llvm {
-  template <typename T> class SmallVectorImpl;
   class Value;
   class Instruction;
   class APInt;
   class TargetData;
+  class StringRef;
   
   /// ComputeMaskedBits - Determine which of the bits specified in Mask are
   /// known to be either zero or one and return them in the KnownZero/KnownOne
@@ -125,16 +124,15 @@ namespace llvm {
     return GetPointerBaseWithConstantOffset(const_cast<Value*>(Ptr), Offset,TD);
   }
   
-  /// GetConstantStringInfo - This function computes the length of a
+  /// getConstantStringInfo - This function computes the length of a
   /// null-terminated C string pointed to by V.  If successful, it returns true
-  /// and returns the string in Str.  If unsuccessful, it returns false.  If
-  /// StopAtNul is set to true (the default), the returned string is truncated
-  /// by a nul character in the global.  If StopAtNul is false, the nul
-  /// character is included in the result string.
-  bool GetConstantStringInfo(const Value *V, std::string &Str,
-                             uint64_t Offset = 0,
-                             bool StopAtNul = true);
-                        
+  /// and returns the string in Str.  If unsuccessful, it returns false.  This
+  /// does not include the trailing nul character by default.  If TrimAtNul is
+  /// set to false, then this returns any trailing nul characters as well as any
+  /// other characters that come after it.
+  bool getConstantStringInfo(const Value *V, StringRef &Str,
+                             uint64_t Offset = 0, bool TrimAtNul = true);
+
   /// GetStringLength - If we can compute the length of the string pointed to by
   /// the specified pointer, return 'len+1'.  If we can't, return 0.
   uint64_t GetStringLength(Value *V);
diff --git a/include/llvm/Constants.h b/include/llvm/Constants.h
index 43f625a68f..a4723d37f0 100644
--- a/include/llvm/Constants.h
+++ b/include/llvm/Constants.h
@@ -352,17 +352,6 @@ public:
   // ConstantArray accessors
   static Constant *get(ArrayType *T, ArrayRef<Constant*> V);
                              
-  /// This method constructs a ConstantArray and initializes it with a text
-  /// string. The default behavior (AddNull==true) causes a null terminator to
-  /// be placed at the end of the array. This effectively increases the length
-  /// of the array by one (you've been warned).  However, in some situations 
-  /// this is not desired so if AddNull==false then the string is copied without
-  /// null termination.
-  
-  // FIXME Remove this.
-  static Constant *get(LLVMContext &Context, StringRef Initializer,
-                       bool AddNull = true);
-  
   /// Transparently provide more efficient getOperand methods.
   DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Constant);
 
@@ -373,31 +362,6 @@ public:
     return reinterpret_cast<ArrayType*>(Value::getType());
   }
 
-  // FIXME: String methods will eventually be removed.
-  
-  
-  /// isString - This method returns true if the array is an array of i8 and
-  /// the elements of the array are all ConstantInt's.
-  bool isString() const;
-
-  /// isCString - This method returns true if the array is a string (see
-  /// @verbatim
-  /// isString) and it ends in a null byte \0 and does not contains any other
-  /// @endverbatim
-  /// null bytes except its terminator.
-  bool isCString() const;
-
-  /// getAsString - If this array is isString(), then this method converts the
-  /// array to an std::string and returns it.  Otherwise, it asserts out.
-  ///
-  std::string getAsString() const;
-
-  /// getAsCString - If this array is isCString(), then this method converts the
-  /// array (without the trailing null byte) to an std::string and returns it.
-  /// Otherwise, it asserts out.
-  ///
-  std::string getAsCString() const;
-
   virtual void destroyConstant();
   virtual void replaceUsesOfWithOnConstant(Value *From, Value *To, Use *U);