test/test-utils.cc

// Copyright 2015, ARM Limited
// All rights reserved.
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// modification, are permitted provided that the following conditions are met:
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#include "test-utils.h"

#include <sys/mman.h>

#include "globals-vixl.h"
#include "a64/cpu-a64.h"

namespace vixl {

ExecutableMemory::ExecutableMemory(size_t size)
  : size_(size),
    buffer_(mmap(NULL, size, PROT_READ | PROT_WRITE | PROT_EXEC,
                 MAP_SHARED | MAP_ANONYMOUS, -1, 0)) {
  VIXL_ASSERT(reinterpret_cast<intptr_t>(buffer_) != -1);
}

ExecutableMemory::~ExecutableMemory() {
  munmap(buffer_, size_);
}

void ExecutableMemory::Write(const byte* code_start, size_t code_size) const {
  VIXL_CHECK(code_size <= size_);
  memcpy(buffer_, code_start, size_);
}

void ExecutableMemory::Execute(int offset) const {
  void (*test_function)(void);

  VIXL_ASSERT((offset >= 0) && (static_cast<size_t>(offset) < size_));
  VIXL_STATIC_ASSERT(sizeof(buffer_) == sizeof(test_function));
  VIXL_STATIC_ASSERT(sizeof(uintptr_t) == sizeof(test_function));
  uintptr_t entry_point = reinterpret_cast<uintptr_t>(buffer_);
  entry_point += offset;
  memcpy(&test_function, &entry_point, sizeof(test_function));

#if defined(__aarch64__)
  aarch64::CPU::EnsureIAndDCacheCoherency(buffer_, size_);
#elif defined(__arm__)
  // TODO: Do not use __builtin___clear_cache and instead implement
  // `CPU::EnsureIAndDCacheCoherency` for aarch32.
  __builtin___clear_cache(buffer_, reinterpret_cast<char*>(buffer_) + size_);
#endif
  test_function();
}

}  // namespace vixl