examples/swap4.cc

// Copyright 2014, ARM Limited
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#include "examples.h"

#define BUF_SIZE (4096)
#define __ masm->

void GenerateSwap4(MacroAssembler* masm) {
  // VIXL's macro assembler provides some functions to manipulate the stack.
  // This example shows some of these functions.
  __ Claim(16);
  __ Poke(x0, 0);
  __ Poke(x1, 8);
  __ Push(x3, x2);

  __ Pop(x1, x0);
  __ Peek(x3, 0);
  __ Peek(x2, 8);
  __ Drop(16);

  __ Ret();
}


#ifndef TEST_EXAMPLES
#ifdef VIXL_INCLUDE_SIMULATOR
int main(void) {
  // Create and initialize the assembler and the simulator.
  byte assm_buf[BUF_SIZE];
  MacroAssembler masm(assm_buf, BUF_SIZE);
  Decoder decoder;
  Simulator simulator(&decoder);

  // Generate the code for the example function.
  Label swap4;
  masm.Bind(&swap4);
  GenerateSwap4(&masm);
  masm.FinalizeCode();

  // Run the example function.
  simulator.set_xreg(0, 0x1111111111111111);
  simulator.set_xreg(1, 0x2222222222222222);
  simulator.set_xreg(2, 0x3333333333333333);
  simulator.set_xreg(3, 0x4444444444444444);

  // clang-format off
  printf("Before swap4:\n"
         "x0 = 0x%" PRIx64 "\n"
         "x1 = 0x%" PRIx64 "\n"
         "x2 = 0x%" PRIx64 "\n"
         "x3 = 0x%" PRIx64 "\n",
         simulator.xreg(0), simulator.xreg(1),
         simulator.xreg(2), simulator.xreg(3));
  // clang-format on

  simulator.RunFrom(masm.GetLabelAddress<Instruction*>(&swap4));

  // clang-format off
  printf("After swap4:\n"
         "x0 = 0x%" PRIx64 "\n"
         "x1 = 0x%" PRIx64 "\n"
         "x2 = 0x%" PRIx64 "\n"
         "x3 = 0x%" PRIx64 "\n",
         simulator.xreg(0), simulator.xreg(1),
         simulator.xreg(2), simulator.xreg(3));
  // clang-format on

  return 0;
}
#else
// Without the simulator there is nothing to test.
int main(void) { return 0; }
#endif  // VIXL_INCLUDE_SIMULATOR
#endif  // TEST_EXAMPLES