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+//===-- ashldi3.c - Implement __ashldi3 -----------------------------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements __ashldi3 for the compiler_rt library.
+//
+//===----------------------------------------------------------------------===//
+
+#include "int_lib.h"
+
+// Returns: a << b
+
+// Precondition: 0 <= b < bits_in_dword
+
+di_int
+__ashldi3(di_int a, si_int b)
+{
+ const int bits_in_word = (int)(sizeof(si_int) * CHAR_BIT);
+ dwords input;
+ dwords result;
+ input.all = a;
+ if (b & bits_in_word) // bits_in_word <= b < bits_in_dword
+ {
+ result.low = 0;
+ result.high = input.low << (b - bits_in_word);
+ }
+ else // 0 <= b < bits_in_word
+ {
+ if (b == 0)
+ return a;
+ result.low = input.low << b;
+ result.high = (input.high << b) | (input.low >> (bits_in_word - b));
+ }
+ return result.all;
+}