1 // Copyright 2016, VIXL authors
2 // All rights reserved.
3 //
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15 //
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26
27 #include "examples.h"
28
29 using namespace vixl;
30 using namespace vixl::aarch32;
31
32 #define __ masm->
33
GenerateAbs(MacroAssembler * masm)34 void GenerateAbs(MacroAssembler* masm) {
35 // int32_t abs(int32_t x)
36 // Argument location:
37 // x -> r0
38
39 __ Cmp(r0, 0);
40 // If r0 is negative, negate r0.
41 __ Rsb(mi, r0, r0, 0);
42 __ Bx(lr);
43 }
44
45
46 #ifndef TEST_EXAMPLES
main()47 int main() {
48 MacroAssembler masm(A32);
49 // Generate the code for the example function.
50 Label abs;
51 masm.Bind(&abs);
52 GenerateAbs(&masm);
53 masm.FinalizeCode();
54 #ifdef VIXL_INCLUDE_SIMULATOR_AARCH32
55 // There is no simulator defined for VIXL AArch32.
56 printf("This example cannot be simulated\n");
57 #else
58 byte* code = masm.GetBuffer()->GetStartAddress<byte*>();
59 uint32_t code_size = masm.GetSizeOfCodeGenerated();
60 ExecutableMemory memory(code, code_size);
61 // Run the example function.
62 int32_t (*abs_function)(int32_t) =
63 memory.GetEntryPoint<int32_t (*)(int32_t)>(abs,
64 masm.GetInstructionSetInUse());
65 int32_t input_value = -42;
66 int32_t output_value = (*abs_function)(input_value);
67 printf("native: abs(%d) = %d\n", input_value, output_value);
68 #endif
69 return 0;
70 }
71 #endif // TEST_EXAMPLES
72