1 // Copyright 2014, VIXL authors 2 // All rights reserved. 3 // 4 // Redistribution and use in source and binary forms, with or without 5 // modification, are permitted provided that the following conditions are met: 6 // 7 // * Redistributions of source code must retain the above copyright notice, 8 // this list of conditions and the following disclaimer. 9 // * Redistributions in binary form must reproduce the above copyright notice, 10 // this list of conditions and the following disclaimer in the documentation 11 // and/or other materials provided with the distribution. 12 // * Neither the name of ARM Limited nor the names of its contributors may be 13 // used to endorse or promote products derived from this software without 14 // specific prior written permission. 15 // 16 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS CONTRIBUTORS "AS IS" AND 17 // ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 18 // WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 19 // DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE 20 // FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 // DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 22 // SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 23 // CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24 // OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 25 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 27 #include "examples.h" 28 29 #define __ masm-> 30 31 void GenerateAbs(MacroAssembler* masm) { 32 // int64_t abs(int64_t x) 33 // Argument location: 34 // x -> x0 35 36 // This example uses a conditional instruction (cneg) to compute the 37 // absolute value of an integer. 38 __ Cmp(x0, 0); 39 __ Cneg(x0, x0, mi); 40 __ Ret(); 41 } 42 43 44 #ifndef TEST_EXAMPLES 45 #ifdef VIXL_INCLUDE_SIMULATOR_AARCH64 46 int main(void) { 47 MacroAssembler masm; 48 Decoder decoder; 49 Simulator simulator(&decoder); 50 51 // Generate the code for the example function. 52 Label abs; 53 masm.Bind(&abs); 54 GenerateAbs(&masm); 55 masm.FinalizeCode(); 56 57 // Run the example function. 58 int64_t input_value = -42; 59 simulator.WriteXRegister(0, input_value); 60 simulator.RunFrom(masm.GetLabelAddress<Instruction*>(&abs)); 61 printf("abs(%" PRId64 ") = %" PRId64 "\n", 62 input_value, 63 simulator.ReadXRegister(0)); 64 65 return 0; 66 } 67 #else 68 // Without the simulator there is nothing to test. 69 int main(void) { return 0; } 70 #endif // VIXL_INCLUDE_SIMULATOR_AARCH64 71 #endif // TEST_EXAMPLES 72
