Properly test the LLVM_USE_RVALUE_REFERENCES macro.

[oota-llvm.git] / include / llvm / Support / LEB128.h

diff --git a/include/llvm/Support/LEB128.h b/include/llvm/Support/LEB128.h
index 00c7eeaebcbb41d66597710411c1332fc462b61f..410edd4dc740af731f5e0ec14aad5d556ea811bf 100644 (file)
--- a/include/llvm/Support/LEB128.h
+++ b/include/llvm/Support/LEB128.h
@@ -19,7 +19,7 @@
 
 namespace llvm {
 
-/// Utility function to encode a SLEB128 value.
+/// Utility function to encode a SLEB128 value to an output stream.
 static inline void encodeSLEB128(int64_t Value, raw_ostream &OS) {
   bool More;
   do {
@@ -34,7 +34,7 @@ static inline void encodeSLEB128(int64_t Value, raw_ostream &OS) {
   } while (More);
 }
 
-/// Utility function to encode a ULEB128 value.
+/// Utility function to encode a ULEB128 value to an output stream.
 static inline void encodeULEB128(uint64_t Value, raw_ostream &OS,
                                  unsigned Padding = 0) {
   do {
@@ -53,6 +53,43 @@ static inline void encodeULEB128(uint64_t Value, raw_ostream &OS,
   }
 }
 
+/// Utility function to encode a ULEB128 value to a buffer. Returns
+/// the length in bytes of the encoded value.
+static inline unsigned encodeULEB128(uint64_t Value, uint8_t *p,
+                                     unsigned Padding = 0) {
+  uint8_t *orig_p = p;
+  do {
+    uint8_t Byte = Value & 0x7f;
+    Value >>= 7;
+    if (Value != 0 || Padding != 0)
+      Byte |= 0x80; // Mark this byte that that more bytes will follow.
+    *p++ = Byte;
+  } while (Value != 0);
+
+  // Pad with 0x80 and emit a null byte at the end.
+  if (Padding != 0) {
+    for (; Padding != 1; --Padding)
+      *p++ = '\x80';
+    *p++ = '\x00';
+  }
+  return (unsigned)(p - orig_p);
+}
+
+
+/// Utility function to decode a ULEB128 value.
+static inline uint64_t decodeULEB128(const uint8_t *p, unsigned *n = 0) {
+  const uint8_t *orig_p = p;
+  uint64_t Value = 0;
+  unsigned Shift = 0;
+  do {
+    Value += (*p & 0x7f) << Shift;
+    Shift += 7;
+  } while (*p++ >= 128);
+  if (n)
+    *n = (unsigned)(p - orig_p);
+  return Value;
+}
+
 }  // namespace llvm
 
 #endif  // LLVM_SYSTEM_LEB128_H