1 files changed, 101 insertions, 0 deletions
diff --git a/lib/Bytecode/Analyzer/ReaderPrimitives.h b/lib/Bytecode/Analyzer/ReaderPrimitives.h
new file mode 100644
index 0000000000..496ab2a5b1
--- /dev/null
+++ b/lib/Bytecode/Analyzer/ReaderPrimitives.h
@@ -0,0 +1,101 @@
+//===-- ReaderPrimitives.h - Bytecode file format reading prims -*- C++ -*-===//
+// 
+//                     The LLVM Compiler Infrastructure
+//
+// This file was developed by the LLVM research group and is distributed under
+// the University of Illinois Open Source License. See LICENSE.TXT for details.
+// 
+//===----------------------------------------------------------------------===//
+//
+// This header defines some basic functions for reading basic primitive types
+// from a bytecode stream.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef READERPRIMITIVES_H
+#define READERPRIMITIVES_H
+
+#include "Support/DataTypes.h"
+#include <string>
+
+namespace llvm {
+
+  static inline unsigned read(const unsigned char *&Buf,
+                              const unsigned char *EndBuf) {
+    if (Buf+4 > EndBuf) throw std::string("Ran out of data!");
+    Buf += 4;
+    return Buf[-4] | (Buf[-3] << 8) | (Buf[-2] << 16) | (Buf[-1] << 24);
+  }
+
+
+  // read_vbr - Read an unsigned integer encoded in variable bitrate format.
+  //
+  static inline unsigned read_vbr_uint(const unsigned char *&Buf, 
+                                       const unsigned char *EndBuf) {
+    unsigned Shift = 0;
+    unsigned Result = 0;
+    
+    do {
+      if (Buf == EndBuf) throw std::string("Ran out of data!");
+      Result |= (unsigned)((*Buf++) & 0x7F) << Shift;
+      Shift += 7;
+    } while (Buf[-1] & 0x80);
+    return Result;
+  }
+  
+  static inline uint64_t read_vbr_uint64(const unsigned char *&Buf, 
+                                         const unsigned char *EndBuf) {
+    unsigned Shift = 0;
+    uint64_t Result = 0;
+    
+    do {
+      if (Buf == EndBuf) throw std::string("Ran out of data!");
+      Result |= (uint64_t)((*Buf++) & 0x7F) << Shift;
+      Shift += 7;
+    } while (Buf[-1] & 0x80);
+    return Result;
+  }
+  
+  static inline int64_t read_vbr_int64(const unsigned char *&Buf, 
+                                       const unsigned char *EndBuf) {
+    uint64_t R = read_vbr_uint64(Buf, EndBuf);
+    if (R & 1) {
+      if (R != 1)
+        return -(int64_t)(R >> 1);
+      else   // There is no such thing as -0 with integers.  "-0" really means
+             // 0x8000000000000000.
+        return 1LL << 63;
+    } else
+      return  (int64_t)(R >> 1);
+  }
+  
+  // align32 - Round up to multiple of 32 bits...
+  static inline void align32(const unsigned char *&Buf, 
+                             const unsigned char *EndBuf) {
+    Buf = (const unsigned char *)((unsigned long)(Buf+3) & (~3UL));
+    if (Buf > EndBuf) throw std::string("Ran out of data!");
+  }
+  
+  static inline std::string read_str(const unsigned char *&Buf,
+                                     const unsigned char *EndBuf) {
+    unsigned Size = read_vbr_uint(Buf, EndBuf);
+    const unsigned char *OldBuf = Buf;
+    Buf += Size;
+    if (Buf > EndBuf)             // Size invalid?
+      throw std::string("Ran out of data reading a string!");
+    return std::string((char*)OldBuf, Size);
+  }
+  
+  static inline void input_data(const unsigned char *&Buf,
+                                const unsigned char *EndBuf, 
+                                void *Ptr, void *End) {
+    unsigned char *Start = (unsigned char *)Ptr;
+    unsigned Amount = (unsigned char *)End - Start;
+    if (Buf+Amount > EndBuf) throw std::string("Ran out of data!");
+    std::copy(Buf, Buf+Amount, Start);
+    Buf += Amount;
+  }
+  
+} // End llvm namespace
+
+#endif