1 // Copyright 2013, ARM Limited
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5 // modification, are permitted provided that the following conditions are met:
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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
main(void)46 int 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