Remove low-signal FileDataLoader allocation-failure tests

Differential Revision: D109506462

Pull Request resolved: #20469

Author: metascroy

extension/data_loader/test/file_data_loader_test.cpp

@@ -8,9 +8,7 @@
 
 #include <executorch/extension/data_loader/file_data_loader.h>
 
-#include <atomic>
 #include <cstring>
-#include <new>
 
 #include <gtest/gtest.h>
 
@@ -27,59 +25,6 @@ using executorch::runtime::Error;
 using executorch::runtime::FreeableBuffer;
 using executorch::runtime::Result;
 
-namespace {
-// When set, the replacement nothrow aligned operator new below returns nullptr,
-// simulating an allocation failure without needing a real OOM.
-std::atomic<bool> g_fail_aligned_nothrow_alloc{false};
-
-// RAII guard to ensure flag is reset even if test asserts early.
-struct FailAllocGuard {
-  FailAllocGuard() {
-    g_fail_aligned_nothrow_alloc.store(true, std::memory_order_relaxed);
-  }
-  ~FailAllocGuard() {
-    g_fail_aligned_nothrow_alloc.store(false, std::memory_order_relaxed);
-  }
-};
-} // namespace
-
-// Detect ASAN to avoid multiple definition link error and to skip test when
-// ASAN runtime provides its own strong operator new.
-#if defined(__SANITIZE_ADDRESS__) || \
-    (defined(__has_feature) && __has_feature(address_sanitizer))
-#define ET_TEST_ASAN_ENABLED 1
-#else
-#define ET_TEST_ASAN_ENABLED 0
-#endif
-
-#if !ET_TEST_ASAN_ENABLED
-// Replaces the global nothrow aligned allocation function for this test binary
-// so FileDataLoader's segment allocation can be made to fail on demand. When
-// the toggle is off it forwards to the real aligned allocator. We call the
-// throwing aligned new inside a try/catch and convert exceptions to nullptr
-// to emulate nothrow semantics without recursing into this same nothrow
-// overload (calling ::operator new(size, alignment, std::nothrow) here would
-// infinite-loop). Memory allocated here is released through the default
-// operator delete, which is not replaced.
-// This is a strong (non-weak) replacement so it reliably overrides libc++'s
-// default on all platforms (a weak definition loses to libc++'s own weak
-// definition on Apple's linker, leaving the override silently unused). Under
-// ASAN this whole block is excluded so it can't clash with ASAN's allocator.
-void* operator new(
-    std::size_t size,
-    std::align_val_t alignment,
-    const std::nothrow_t& /* tag */) noexcept {
-  if (g_fail_aligned_nothrow_alloc.load(std::memory_order_relaxed)) {
-    return nullptr;
-  }
-  try {
-    return ::operator new(size, alignment);
-  } catch (...) {
-    return nullptr;
-  }
-}
-#endif // !ET_TEST_ASAN_ENABLED
-
 class FileDataLoaderTest : public ::testing::TestWithParam<size_t> {
  protected:
   void SetUp() override {
@@ -202,46 +147,6 @@ TEST_P(FileDataLoaderTest, OutOfBoundsLoadFails) {
   }
 }
 
-#if !ET_TEST_ASAN_ENABLED
-TEST_P(FileDataLoaderTest, AllocationFailureDuringLoadReturnsError) {
-  // Create a temp file; contents don't matter.
-  uint8_t data[256] = {};
-  TempFile tf(data, sizeof(data));
-
-  Result<FileDataLoader> fdl =
-      FileDataLoader::from(tf.path().c_str(), alignment());
-  ASSERT_EQ(fdl.error(), Error::Ok);
-
-  // Force the segment allocation inside load() to fail. The loader must surface
-  // Error::MemoryAllocationFailed rather than letting std::bad_alloc escape,
-  // which would abort the process in the exception-free runtime.
-  FailAllocGuard fail_guard;
-  Result<FreeableBuffer> fb = fdl->load(
-      /*offset=*/0,
-      /*size=*/sizeof(data),
-      DataLoader::SegmentInfo(DataLoader::SegmentInfo::Type::Program));
-
-  EXPECT_EQ(fb.error(), Error::MemoryAllocationFailed);
-}
-#endif // !ET_TEST_ASAN_ENABLED
-
-#if !ET_TEST_ASAN_ENABLED
-TEST_P(FileDataLoaderTest, AllocationFailureDuringFromReturnsError) {
-  // Create a temp file; contents don't matter.
-  uint8_t data[256] = {};
-  TempFile tf(data, sizeof(data));
-
-  // Force the filename allocation inside from() to fail. FileDataLoader::from
-  // copies the filename using et_aligned_alloc and must return
-  // Error::MemoryAllocationFailed on nullptr rather than throwing.
-  FailAllocGuard fail_guard;
-  Result<FileDataLoader> fdl =
-      FileDataLoader::from(tf.path().c_str(), alignment());
-
-  EXPECT_EQ(fdl.error(), Error::MemoryAllocationFailed);
-}
-#endif // !ET_TEST_ASAN_ENABLED
-
 TEST_P(FileDataLoaderTest, FromMissingFileFails) {
   // Wrapping a file that doesn't exist should fail.
   Result<FileDataLoader> fdl = FileDataLoader::from(