1 // Copyright 2016, VIXL authors
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26
27 #include "examples.h"
28
29 #define __ masm->
30
GenerateAbs(MacroAssembler * masm)31 void GenerateAbs(MacroAssembler* masm) {
32 // int32_t abs(int32_t x)
33 // Argument location:
34 // x -> r0
35
36 __ Cmp(r0, 0);
37 // If r0 is negative, negate r0.
38 __ Rsb(mi, r0, r0, 0);
39 __ Bx(lr);
40 }
41
42
43 #ifndef TEST_EXAMPLES
main()44 int main() {
45 MacroAssembler masm(A32);
46 // Generate the code for the example function.
47 Label abs;
48 masm.Bind(&abs);
49 GenerateAbs(&masm);
50 masm.FinalizeCode();
51 #ifdef VIXL_INCLUDE_SIMULATOR_AARCH32
52 // There is no simulator defined for VIXL AArch32.
53 printf("This example cannot be simulated\n");
54 #else
55 byte* code = masm.GetBuffer()->GetStartAddress<byte*>();
56 uint32_t code_size = masm.GetSizeOfCodeGenerated();
57 ExecutableMemory memory(code, code_size);
58 // Run the example function.
59 int32_t (*abs_function)(int32_t) =
60 memory.GetEntryPoint<int32_t (*)(int32_t)>(abs,
61 masm.GetInstructionSetInUse());
62 int32_t input_value = -42;
63 int32_t output_value = (*abs_function)(input_value);
64 printf("native: abs(%d) = %d\n", input_value, output_value);
65 #endif
66 return 0;
67 }
68 #endif // TEST_EXAMPLES
69