1*638d2b51SSandrine Bailleux /* ===-- lshrdi3.c - Implement __lshrdi3 -----------------------------------=== 2*638d2b51SSandrine Bailleux * 3*638d2b51SSandrine Bailleux * The LLVM Compiler Infrastructure 4*638d2b51SSandrine Bailleux * 5*638d2b51SSandrine Bailleux * This file is dual licensed under the MIT and the University of Illinois Open 6*638d2b51SSandrine Bailleux * Source Licenses. See LICENSE.TXT for details. 7*638d2b51SSandrine Bailleux * 8*638d2b51SSandrine Bailleux * ===----------------------------------------------------------------------=== 9*638d2b51SSandrine Bailleux * 10*638d2b51SSandrine Bailleux * This file implements __lshrdi3 for the compiler_rt library. 11*638d2b51SSandrine Bailleux * 12*638d2b51SSandrine Bailleux * ===----------------------------------------------------------------------=== 13*638d2b51SSandrine Bailleux */ 14*638d2b51SSandrine Bailleux 15*638d2b51SSandrine Bailleux #include "int_lib.h" 16*638d2b51SSandrine Bailleux 17*638d2b51SSandrine Bailleux /* Returns: logical a >> b */ 18*638d2b51SSandrine Bailleux 19*638d2b51SSandrine Bailleux /* Precondition: 0 <= b < bits_in_dword */ 20*638d2b51SSandrine Bailleux 21*638d2b51SSandrine Bailleux COMPILER_RT_ABI di_int 22*638d2b51SSandrine Bailleux __lshrdi3(di_int a, si_int b) 23*638d2b51SSandrine Bailleux { 24*638d2b51SSandrine Bailleux const int bits_in_word = (int)(sizeof(si_int) * CHAR_BIT); 25*638d2b51SSandrine Bailleux udwords input; 26*638d2b51SSandrine Bailleux udwords result; 27*638d2b51SSandrine Bailleux input.all = a; 28*638d2b51SSandrine Bailleux if (b & bits_in_word) /* bits_in_word <= b < bits_in_dword */ 29*638d2b51SSandrine Bailleux { 30*638d2b51SSandrine Bailleux result.s.high = 0; 31*638d2b51SSandrine Bailleux result.s.low = input.s.high >> (b - bits_in_word); 32*638d2b51SSandrine Bailleux } 33*638d2b51SSandrine Bailleux else /* 0 <= b < bits_in_word */ 34*638d2b51SSandrine Bailleux { 35*638d2b51SSandrine Bailleux if (b == 0) 36*638d2b51SSandrine Bailleux return a; 37*638d2b51SSandrine Bailleux result.s.high = input.s.high >> b; 38*638d2b51SSandrine Bailleux result.s.low = (input.s.high << (bits_in_word - b)) | (input.s.low >> b); 39*638d2b51SSandrine Bailleux } 40*638d2b51SSandrine Bailleux return result.all; 41*638d2b51SSandrine Bailleux } 42*638d2b51SSandrine Bailleux 43*638d2b51SSandrine Bailleux #if defined(__ARM_EABI__) 44*638d2b51SSandrine Bailleux AEABI_RTABI di_int __aeabi_llsr(di_int a, si_int b) COMPILER_RT_ALIAS(__lshrdi3); 45*638d2b51SSandrine Bailleux #endif 46