examples/aarch32/abs.cc

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#include "examples.h"

#define __ masm->

void GenerateAbs(MacroAssembler* masm) {
  // int32_t abs(int32_t x)
  // Argument location:
  //   x -> r0

  __ Cmp(r0, 0);
  // If r0 is negative, negate r0.
  __ Rsb(mi, r0, r0, 0);
  __ Bx(lr);
}


#ifndef TEST_EXAMPLES
int main() {
  MacroAssembler masm(A32);
  // Generate the code for the example function.
  Label abs;
  masm.Bind(&abs);
  GenerateAbs(&masm);
  masm.FinalizeCode();
#ifdef VIXL_INCLUDE_SIMULATOR_AARCH32
  // There is no simulator defined for VIXL AArch32.
  printf("This example cannot be simulated\n");
#else
  byte* code = masm.GetBuffer()->GetStartAddress<byte*>();
  uint32_t code_size = masm.GetSizeOfCodeGenerated();
  ExecutableMemory memory(code, code_size);
  // Run the example function.
  int32_t (*abs_function)(int32_t) =
      memory.GetEntryPoint<int32_t (*)(int32_t)>(abs);
  int32_t input_value = -42;
  int32_t output_value = (*abs_function)(input_value);
  printf("native: abs(%d) = %d\n", input_value, output_value);
#endif
  return 0;
}
#endif  // TEST_EXAMPLES