Shrinking alloy memory interface so that alloy-sandbox doesn't need xe.

src/alloy/memory.cc

@@ -61,4 +61,43 @@ uint64_t Memory::SearchAligned(uint64_t start, uint64_t end,
   return 0;
 }
 
+SimpleMemory::SimpleMemory(size_t capacity) : memory_(capacity) {
+  membase_ = reinterpret_cast<uint8_t*>(memory_.data());
+  reserve_address_ = capacity - 8;
+}
+
+SimpleMemory::~SimpleMemory() = default;
+
+uint8_t SimpleMemory::LoadI8(uint64_t address) {
+  return poly::load<uint8_t>(membase_ + address);
+}
+
+uint16_t SimpleMemory::LoadI16(uint64_t address) {
+  return poly::load<uint16_t>(membase_ + address);
+}
+
+uint32_t SimpleMemory::LoadI32(uint64_t address) {
+  return poly::load<uint32_t>(membase_ + address);
+}
+
+uint64_t SimpleMemory::LoadI64(uint64_t address) {
+  return poly::load<uint64_t>(membase_ + address);
+}
+
+void SimpleMemory::StoreI8(uint64_t address, uint8_t value) {
+  poly::store<uint8_t>(membase_ + address, value);
+}
+
+void SimpleMemory::StoreI16(uint64_t address, uint16_t value) {
+  poly::store<uint16_t>(membase_ + address, value);
+}
+
+void SimpleMemory::StoreI32(uint64_t address, uint32_t value) {
+  poly::store<uint32_t>(membase_ + address, value);
+}
+
+void SimpleMemory::StoreI64(uint64_t address, uint64_t value) {
+  poly::store<uint64_t>(membase_ + address, value);
+}
+
 }  // namespace alloy