1*3cab2bb3Spatrick //===-- multi3.c - Implement __multi3 -------------------------------------===// 2*3cab2bb3Spatrick // 3*3cab2bb3Spatrick // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4*3cab2bb3Spatrick // See https://llvm.org/LICENSE.txt for license information. 5*3cab2bb3Spatrick // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6*3cab2bb3Spatrick // 7*3cab2bb3Spatrick //===----------------------------------------------------------------------===// 8*3cab2bb3Spatrick // 9*3cab2bb3Spatrick // This file implements __multi3 for the compiler_rt library. 10*3cab2bb3Spatrick // 11*3cab2bb3Spatrick //===----------------------------------------------------------------------===// 12*3cab2bb3Spatrick 13*3cab2bb3Spatrick #include "int_lib.h" 14*3cab2bb3Spatrick 15*3cab2bb3Spatrick #ifdef CRT_HAS_128BIT 16*3cab2bb3Spatrick 17*3cab2bb3Spatrick // Returns: a * b 18*3cab2bb3Spatrick __mulddi3(du_int a,du_int b)19*3cab2bb3Spatrickstatic ti_int __mulddi3(du_int a, du_int b) { 20*3cab2bb3Spatrick twords r; 21*3cab2bb3Spatrick const int bits_in_dword_2 = (int)(sizeof(di_int) * CHAR_BIT) / 2; 22*3cab2bb3Spatrick const du_int lower_mask = (du_int)~0 >> bits_in_dword_2; 23*3cab2bb3Spatrick r.s.low = (a & lower_mask) * (b & lower_mask); 24*3cab2bb3Spatrick du_int t = r.s.low >> bits_in_dword_2; 25*3cab2bb3Spatrick r.s.low &= lower_mask; 26*3cab2bb3Spatrick t += (a >> bits_in_dword_2) * (b & lower_mask); 27*3cab2bb3Spatrick r.s.low += (t & lower_mask) << bits_in_dword_2; 28*3cab2bb3Spatrick r.s.high = t >> bits_in_dword_2; 29*3cab2bb3Spatrick t = r.s.low >> bits_in_dword_2; 30*3cab2bb3Spatrick r.s.low &= lower_mask; 31*3cab2bb3Spatrick t += (b >> bits_in_dword_2) * (a & lower_mask); 32*3cab2bb3Spatrick r.s.low += (t & lower_mask) << bits_in_dword_2; 33*3cab2bb3Spatrick r.s.high += t >> bits_in_dword_2; 34*3cab2bb3Spatrick r.s.high += (a >> bits_in_dword_2) * (b >> bits_in_dword_2); 35*3cab2bb3Spatrick return r.all; 36*3cab2bb3Spatrick } 37*3cab2bb3Spatrick 38*3cab2bb3Spatrick // Returns: a * b 39*3cab2bb3Spatrick __multi3(ti_int a,ti_int b)40*3cab2bb3SpatrickCOMPILER_RT_ABI ti_int __multi3(ti_int a, ti_int b) { 41*3cab2bb3Spatrick twords x; 42*3cab2bb3Spatrick x.all = a; 43*3cab2bb3Spatrick twords y; 44*3cab2bb3Spatrick y.all = b; 45*3cab2bb3Spatrick twords r; 46*3cab2bb3Spatrick r.all = __mulddi3(x.s.low, y.s.low); 47*3cab2bb3Spatrick r.s.high += x.s.high * y.s.low + x.s.low * y.s.high; 48*3cab2bb3Spatrick return r.all; 49*3cab2bb3Spatrick } 50*3cab2bb3Spatrick 51*3cab2bb3Spatrick #endif // CRT_HAS_128BIT 52