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-rw-r--r--contrib/llvm/lib/Support/LEB128.cpp44
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diff --git a/contrib/llvm/lib/Support/LEB128.cpp b/contrib/llvm/lib/Support/LEB128.cpp
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+//===- LEB128.cpp - LEB128 utility functions implementation -----*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements some utility functions for encoding SLEB128 and
+// ULEB128 values.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Support/LEB128.h"
+
+namespace llvm {
+
+/// Utility function to get the size of the ULEB128-encoded value.
+unsigned getULEB128Size(uint64_t Value) {
+ unsigned Size = 0;
+ do {
+ Value >>= 7;
+ Size += sizeof(int8_t);
+ } while (Value);
+ return Size;
+}
+
+/// Utility function to get the size of the SLEB128-encoded value.
+unsigned getSLEB128Size(int64_t Value) {
+ unsigned Size = 0;
+ int Sign = Value >> (8 * sizeof(Value) - 1);
+ bool IsMore;
+
+ do {
+ unsigned Byte = Value & 0x7f;
+ Value >>= 7;
+ IsMore = Value != Sign || ((Byte ^ Sign) & 0x40) != 0;
+ Size += sizeof(int8_t);
+ } while (IsMore);
+ return Size;
+}
+
+} // namespace llvm