1// Copyright 2014, VIXL authors
2// All rights reserved.
3//
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5// modification, are permitted provided that the following conditions are met:
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11//     and/or other materials provided with the distribution.
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15//
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26
27#include "examples.h"
28
29#define __ masm->
30
31void 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
46int 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.
69int main(void) { return 0; }
70#endif  // VIXL_INCLUDE_SIMULATOR_AARCH64
71#endif  // TEST_EXAMPLES
72