1156cd587Sjoerg /* ===-- ashrti3.c - Implement __ashrti3 -----------------------------------=== 2156cd587Sjoerg * 3156cd587Sjoerg * The LLVM Compiler Infrastructure 4156cd587Sjoerg * 5156cd587Sjoerg * This file is dual licensed under the MIT and the University of Illinois Open 6156cd587Sjoerg * Source Licenses. See LICENSE.TXT for details. 7156cd587Sjoerg * 8156cd587Sjoerg * ===----------------------------------------------------------------------=== 9156cd587Sjoerg * 10156cd587Sjoerg * This file implements __ashrti3 for the compiler_rt library. 11156cd587Sjoerg * 12156cd587Sjoerg * ===----------------------------------------------------------------------=== 13156cd587Sjoerg */ 14156cd587Sjoerg 15156cd587Sjoerg #include "int_lib.h" 16156cd587Sjoerg 17156cd587Sjoerg #ifdef CRT_HAS_128BIT 18156cd587Sjoerg 19156cd587Sjoerg /* Returns: arithmetic a >> b */ 20156cd587Sjoerg 21156cd587Sjoerg /* Precondition: 0 <= b < bits_in_tword */ 22156cd587Sjoerg 23*f7f78b33Sjoerg COMPILER_RT_ABI ti_int __ashrti3(ti_int a,si_int b)24156cd587Sjoerg__ashrti3(ti_int a, si_int b) 25156cd587Sjoerg { 26156cd587Sjoerg const int bits_in_dword = (int)(sizeof(di_int) * CHAR_BIT); 27156cd587Sjoerg twords input; 28156cd587Sjoerg twords result; 29156cd587Sjoerg input.all = a; 30156cd587Sjoerg if (b & bits_in_dword) /* bits_in_dword <= b < bits_in_tword */ 31156cd587Sjoerg { 32156cd587Sjoerg /* result.s.high = input.s.high < 0 ? -1 : 0 */ 33156cd587Sjoerg result.s.high = input.s.high >> (bits_in_dword - 1); 34156cd587Sjoerg result.s.low = input.s.high >> (b - bits_in_dword); 35156cd587Sjoerg } 36156cd587Sjoerg else /* 0 <= b < bits_in_dword */ 37156cd587Sjoerg { 38156cd587Sjoerg if (b == 0) 39156cd587Sjoerg return a; 40156cd587Sjoerg result.s.high = input.s.high >> b; 41156cd587Sjoerg result.s.low = (input.s.high << (bits_in_dword - b)) | (input.s.low >> b); 42156cd587Sjoerg } 43156cd587Sjoerg return result.all; 44156cd587Sjoerg } 45156cd587Sjoerg 46156cd587Sjoerg #endif /* CRT_HAS_128BIT */ 47