1 // Copyright 2014, ARM Limited
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26
27 #include "examples.h"
28
29 #define BUF_SIZE (4096)
30 #define __ masm->
31
GenerateAbs(MacroAssembler * masm)32 void 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
46 #ifdef USE_SIMULATOR
main(void)47 int main(void) {
48 // Create and initialize the assembler and the simulator.
49 byte assm_buf[BUF_SIZE];
50 MacroAssembler masm(assm_buf, BUF_SIZE);
51 Decoder decoder;
52 Simulator simulator(&decoder);
53
54 // Generate the code for the example function.
55 Label abs;
56 masm.Bind(&abs);
57 GenerateAbs(&masm);
58 masm.FinalizeCode();
59
60 // Run the example function.
61 int64_t input_value = -42;
62 simulator.set_xreg(0, input_value);
63 simulator.RunFrom(masm.GetLabelAddress<Instruction*>(&abs));
64 printf("abs(%ld) = %ld\n", input_value, simulator.xreg(0));
65
66 return 0;
67 }
68 #else
69 // Without the simulator there is nothing to test.
main(void)70 int main(void) { return 0; }
71 #endif // USE_SIMULATOR
72 #endif // TEST_EXAMPLES
73