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-rw-r--r--lib/builtins/ashrdi3.c44
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diff --git a/lib/builtins/ashrdi3.c b/lib/builtins/ashrdi3.c
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+/*===-- ashrdi3.c - Implement __ashrdi3 -----------------------------------===
+ *
+ * The LLVM Compiler Infrastructure
+ *
+ * This file is dual licensed under the MIT and the University of Illinois Open
+ * Source Licenses. See LICENSE.TXT for details.
+ *
+ * ===----------------------------------------------------------------------===
+ *
+ * This file implements __ashrdi3 for the compiler_rt library.
+ *
+ * ===----------------------------------------------------------------------===
+ */
+
+#include "int_lib.h"
+
+/* Returns: arithmetic a >> b */
+
+/* Precondition: 0 <= b < bits_in_dword */
+
+ARM_EABI_FNALIAS(lasr, ashrdi3)
+
+COMPILER_RT_ABI di_int
+__ashrdi3(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.s.high = input.s.high < 0 ? -1 : 0 */
+ result.s.high = input.s.high >> (bits_in_word - 1);
+ result.s.low = input.s.high >> (b - bits_in_word);
+ }
+ else /* 0 <= b < bits_in_word */
+ {
+ if (b == 0)
+ return a;
+ result.s.high = input.s.high >> b;
+ result.s.low = (input.s.high << (bits_in_word - b)) | (input.s.low >> b);
+ }
+ return result.all;
+}