1*0a6a1f1dSLionel Sambuc /*===-- ashrdi3.c - Implement __ashrdi3 -----------------------------------=== 2*0a6a1f1dSLionel Sambuc * 3*0a6a1f1dSLionel Sambuc * The LLVM Compiler Infrastructure 4*0a6a1f1dSLionel Sambuc * 5*0a6a1f1dSLionel Sambuc * This file is dual licensed under the MIT and the University of Illinois Open 6*0a6a1f1dSLionel Sambuc * Source Licenses. See LICENSE.TXT for details. 7*0a6a1f1dSLionel Sambuc * 8*0a6a1f1dSLionel Sambuc * ===----------------------------------------------------------------------=== 9*0a6a1f1dSLionel Sambuc * 10*0a6a1f1dSLionel Sambuc * This file implements __ashrdi3 for the compiler_rt library. 11*0a6a1f1dSLionel Sambuc * 12*0a6a1f1dSLionel Sambuc * ===----------------------------------------------------------------------=== 13*0a6a1f1dSLionel Sambuc */ 14*0a6a1f1dSLionel Sambuc 15*0a6a1f1dSLionel Sambuc #include "int_lib.h" 16*0a6a1f1dSLionel Sambuc 17*0a6a1f1dSLionel Sambuc /* Returns: arithmetic a >> b */ 18*0a6a1f1dSLionel Sambuc 19*0a6a1f1dSLionel Sambuc /* Precondition: 0 <= b < bits_in_dword */ 20*0a6a1f1dSLionel Sambuc ARM_EABI_FNALIAS(lasr,ashrdi3)21*0a6a1f1dSLionel SambucARM_EABI_FNALIAS(lasr, ashrdi3) 22*0a6a1f1dSLionel Sambuc 23*0a6a1f1dSLionel Sambuc COMPILER_RT_ABI di_int 24*0a6a1f1dSLionel Sambuc __ashrdi3(di_int a, si_int b) 25*0a6a1f1dSLionel Sambuc { 26*0a6a1f1dSLionel Sambuc const int bits_in_word = (int)(sizeof(si_int) * CHAR_BIT); 27*0a6a1f1dSLionel Sambuc dwords input; 28*0a6a1f1dSLionel Sambuc dwords result; 29*0a6a1f1dSLionel Sambuc input.all = a; 30*0a6a1f1dSLionel Sambuc if (b & bits_in_word) /* bits_in_word <= b < bits_in_dword */ 31*0a6a1f1dSLionel Sambuc { 32*0a6a1f1dSLionel Sambuc /* result.s.high = input.s.high < 0 ? -1 : 0 */ 33*0a6a1f1dSLionel Sambuc result.s.high = input.s.high >> (bits_in_word - 1); 34*0a6a1f1dSLionel Sambuc result.s.low = input.s.high >> (b - bits_in_word); 35*0a6a1f1dSLionel Sambuc } 36*0a6a1f1dSLionel Sambuc else /* 0 <= b < bits_in_word */ 37*0a6a1f1dSLionel Sambuc { 38*0a6a1f1dSLionel Sambuc if (b == 0) 39*0a6a1f1dSLionel Sambuc return a; 40*0a6a1f1dSLionel Sambuc result.s.high = input.s.high >> b; 41*0a6a1f1dSLionel Sambuc result.s.low = (input.s.high << (bits_in_word - b)) | (input.s.low >> b); 42*0a6a1f1dSLionel Sambuc } 43*0a6a1f1dSLionel Sambuc return result.all; 44*0a6a1f1dSLionel Sambuc } 45