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      1 // Copyright 2016, VIXL authors
      2 // All rights reserved.
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      4 // Redistribution and use in source and binary forms, with or without
      5 // modification, are permitted provided that the following conditions are met:
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      9 //   * Redistributions in binary form must reproduce the above copyright notice,
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     26 
     27 #include "examples.h"
     28 
     29 #define __ masm->
     30 
     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
     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