Rework the routines that convert AP[S]Int into a string. Now, instead of

returning an std::string by value, it fills in a SmallString/SmallVector
passed in.  This significantly reduces string thrashing in some cases.

More specifically, this:
 - Adds an operator<< and a print method for APInt that allows you to 
   directly send them to an ostream.
 - Reimplements APInt::toString to be much simpler and more efficient
   algorithmically in addition to not thrashing strings quite as much.

This speeds up llvm-dis on kc++ by 7%, and may also slightly speed up the
asmprinter.  This also fixes a bug I introduced into the asmwriter in a
previous patch w.r.t. alias printing.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54873 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 14 insertions, 4 deletions

diff --git a/include/llvm/ADT/APSInt.h b/include/llvm/ADT/APSInt.h
index edb36bafe4..00bece62ad 100644
--- a/include/llvm/ADT/APSInt.h
+++ b/include/llvm/ADT/APSInt.h
@@ -19,7 +19,6 @@
 
 namespace llvm {
   
-  
 class APSInt : public APInt {
   bool IsUnsigned;
 public:
@@ -58,11 +57,16 @@ public:
   void setIsUnsigned(bool Val) { IsUnsigned = Val; }
   void setIsSigned(bool Val) { IsUnsigned = !Val; }
   
-  /// This is used internally to convert an APInt to a string.
-  /// @brief Converts an APInt to a std::string
-  std::string toString(uint8_t Radix = 10) const {
+  /// toString - Append this APSInt to the specified SmallString.
+  void toString(SmallVectorImpl<char> &Str, unsigned Radix = 10) const {
+    return APInt::toString(Str, Radix, isSigned());
+  }
+  /// toString - Converts an APInt to a std::string.  This is an inefficient
+  /// method, your should prefer passing in a SmallString instead.
+  std::string toString(unsigned Radix) const {
     return APInt::toString(Radix, isSigned());
   }
+  using APInt::toString;
   
   APSInt& extend(uint32_t width) {
     if (IsUnsigned)
@@ -235,6 +239,12 @@ public:
   void Profile(FoldingSetNodeID& ID) const;
 };
   
+inline std::ostream &operator<<(std::ostream &OS, const APSInt &I) {
+  I.print(OS, I.isSigned());
+  return OS;
+}
+  
+  
 } // end namespace llvm
 
 #endif