Function testMemoryGrowReadWriteBase

deps/v8/test/mjsunit/wasm/grow-memory.js:46–110

(size, load_fn, store_fn)

function testMemoryGrowReadWriteBase(size, load_fn, store_fn) {
  // size is the number of bytes for load and stores.
  var builder = genMemoryGrowBuilder();
  builder.addMemory(1, undefined);
  var module = builder.instantiate();
  var offset;
  var load = module.exports[load_fn];
  var store = module.exports[store_fn];
  function peek() { return load(offset); }
  function poke(value) { return store(offset, value); }
  function growMem(pages) { return module.exports.grow_memory(pages); }

  // Instead of checking every n-th offset, check the first 5.
  for(offset = 0; offset <= (4*size); offset+=size) {
    poke(20);
    assertEquals(20, peek());
  }
  for (offset = kPageSize - (size - 1); offset < kPageSize + size; offset++) {
    assertTraps(kTrapMemOutOfBounds, poke);
    assertTraps(kTrapMemOutOfBounds, peek);
  }

  assertEquals(1, growMem(3));

  for (let n = 1; n <= 3; n++) {
    for (offset = n * kPageSize - 5 * size; offset <= n * kPageSize + 4 * size;
         offset += size) {
      // Check the 5 offsets to the before and after the n-th page.
      //    page n-1              page n          page n+1
      //    +---- ... ------------+---------- ... +------ ...
      //    | | | ... | | | | | | | | | | | | ... | | | | ...
      //      <+>       ^                 ^
      //       |        first offset      last offset
      //       +-> size bytes
      poke(20);
      assertEquals(20, peek());
    }
  }

  // Check the last 5 valid offsets of the last page.
  for (offset = 4*kPageSize-size-(4*size); offset <= 4*kPageSize -size; offset+=size) {
    poke(20);
    assertEquals(20, peek());
  }

  for (offset = 4*kPageSize - (size-1); offset < 4*kPageSize + size; offset++) {
    assertTraps(kTrapMemOutOfBounds, poke);
    assertTraps(kTrapMemOutOfBounds, peek);
  }

  assertEquals(4, growMem(15));

  for (offset = 4*kPageSize - (size-1); offset <= 4*kPageSize + size; offset+=size) {
    poke(20);
    assertEquals(20, peek());
  }
  for (offset = 19*kPageSize - 10; offset <= 19*kPageSize - size; offset+=size) {
    poke(20);