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diff --git a/lib/lshrdi3.c b/lib/lshrdi3.c
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+//===-- lshrdi3.c - Implement __lshrdi3 -----------------------------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements __lshrdi3 for the compiler_rt library.
+//
+//===----------------------------------------------------------------------===//
+
+#include "int_lib.h"
+
+// Returns: logical a >> b
+
+// Precondition: 0 <= b < bits_in_dword
+
+di_int
+__lshrdi3(di_int a, si_int b)
+{
+ const int bits_in_word = (int)(sizeof(si_int) * CHAR_BIT);
+ udwords input;
+ udwords result;
+ input.all = a;
+ if (b & bits_in_word) // bits_in_word <= b < bits_in_dword
+ {
+ result.high = 0;
+ result.low = input.high >> (b - bits_in_word);
+ }
+ else // 0 <= b < bits_in_word
+ {
+ if (b == 0)
+ return a;
+ result.high = input.high >> b;
+ result.low = (input.high << (bits_in_word - b)) | (input.low >> b);
+ }
+ return result.all;
+}