1// Copyright 2013, ARM Limited
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26
27#include "examples.h"
28
29#define ARRAY_SIZE(Array) (sizeof(Array) / sizeof((Array)[0]))
30#define BUF_SIZE (4096)
31#define __ masm->
32
33void GenerateSumArray(MacroAssembler* masm) {
34  // uint32_t sum_array(uint8_t* array, uint32_t size)
35  //  Argument locations:
36  //    array (pointer) -> x0
37  //    size            -> x1
38
39  Label loop, end;
40
41  __ Mov(x2, x0);
42  __ Mov(w0, 0);
43
44  // There's nothing to do if the array is empty.
45  __ Cbz(w1, &end);
46
47  // Go through the array and sum the elements.
48  __ Bind(&loop);
49
50  __ Ldrb(w3, MemOperand(x2, 1, PostIndex));  // w3 = *(x2++)
51  __ Add(w0, w0, w3);
52
53  __ Sub(w1, w1, 1);
54  __ Cbnz(w1, &loop);
55
56  __ Bind(&end);
57  __ Ret();
58}
59
60
61#ifndef TEST_EXAMPLES
62int main(void) {
63  // Create and initialize the assembler and the simulator.
64  byte assm_buf[BUF_SIZE];
65  MacroAssembler masm(assm_buf, BUF_SIZE);
66  Decoder decoder;
67  Simulator simulator(&decoder);
68
69  // Generate the code for the example function.
70  Label sum_array;
71  masm.Bind(&sum_array);
72  GenerateSumArray(&masm);
73  masm.FinalizeCode();
74
75  // Run the example function.
76  uint8_t data[] = { 2, 45, 63, 7, 245, 38 };
77  uintptr_t data_addr = reinterpret_cast<uintptr_t>(data);
78  simulator.set_xreg(0, data_addr);
79  simulator.set_xreg(1, ARRAY_SIZE(data));
80  simulator.RunFrom(sum_array.target());
81
82  unsigned int i;
83  for (i = 0; i < ARRAY_SIZE(data) - 1; ++i) {
84    printf("%d + ", data[i]);
85  }
86  printf("%d = %d\n", data[i], simulator.wreg(0));
87
88  return 0;
89}
90#endif
91