1// Copyright 2013, ARM Limited
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26
27#include "examples.h"
28
29#define BUF_SIZE (4096)
30#define __ masm->
31
32void GenerateAbs(MacroAssembler* masm) {
33  // int64_t abs(int64_t x)
34  // Argument location:
35  //   x -> x0
36
37  // This example uses a conditional instruction (cneg) to compute the
38  // absolute value of an integer.
39  __ Cmp(x0, 0);
40  __ Cneg(x0, x0, mi);
41  __ Ret();
42}
43
44
45#ifndef TEST_EXAMPLES
46int main(void) {
47  // Create and initialize the assembler and the simulator.
48  byte assm_buf[BUF_SIZE];
49  MacroAssembler masm(assm_buf, BUF_SIZE);
50  Decoder decoder;
51  Simulator simulator(&decoder);
52
53  // Generate the code for the example function.
54  Label abs;
55  masm.Bind(&abs);
56  GenerateAbs(&masm);
57  masm.FinalizeCode();
58
59  // Run the example function.
60  int64_t input_value = -42;
61  simulator.set_xreg(0, input_value);
62  simulator.RunFrom(abs.target());
63  printf("abs(%ld) = %ld\n", input_value, simulator.xreg(0));
64
65  return 0;
66}
67#endif
68