trunk/053eaef2c546cc3dfe715cc995a70d2b20e6a075: Fix Windows cpp wrapper int array FileCheck (#185145)

The Windows CPU cpp-wrapper repro in #162366 still had a test expectation that assumed generated C++ int64 array literals always use the L suffix. MSVC-generated code uses LL for these literals, and the test already had the same platform split elsewhere through target_assert_size_stride_str. That made CPUReproTests.test_require_stride_order_non_owning fail on Windows even when the generated allocation and stride-order behavior was correct.

Factor the cpp-wrapper int-array formatting into cpp_int_array_str() and reuse it in both the existing assert-size-stride helper and the repro test. This keeps the expectation tied to the platform-specific generated C++ spelling instead of hard-coding Linux formatting in the Windows test path.

The attached convolution_backward C-shim failures from the issue are already addressed on current main by 1b421fae114 [inductor] Fix MSVC const pointer emission in cpp wrapper temporary arrays (#179846), so this change is limited to the remaining Windows-sensitive FileCheck expectation.

Fixes #162366
Generated by my agent

Test Plan:

• TORCHINDUCTOR_CPP_WRAPPER=1 python - <<'PY'
  import runpy
  import sys
  sys.modules['torchvision'] = None
  sys.path.insert(0, 'test/inductor')
  sys.argv = ['test/inductor/test_cpu_repro.py', 'CPUReproTests.test_require_stride_order_non_owning']
  runpy.run_path('test/inductor/test_cpu_repro.py', run_name='main')
  PY
• python - <<'PY'
  import sys
  sys.modules['torchvision'] = None
  sys.path.insert(0, 'test/inductor')
  import test_torchinductor
  orig = sys.platform
  try:
  sys.platform = 'win32'
  assert test_torchinductor.cpp_int_array_str([2, 3, 4, 4]) == '{2LL, 3LL, 4LL, 4LL}'
  sys.platform = 'linux'
  assert test_torchinductor.cpp_int_array_str([2, 3, 4, 4]) == '{2L, 3L, 4L, 4L}'
  finally:
  sys.platform = orig
  print('cpp_int_array_str platform formatting OK')
  PY
• TORCHINDUCTOR_CPP_WRAPPER=1 python - <<'PY'
  import runpy
  import sys
  sys.modules['torchvision'] = None
  sys.path.insert(0, 'test/inductor')
  sys.argv = ['test/inductor/test_torchinductor.py', 'CpuTests.test_conv_backward_cpu']
  runpy.run_path('test/inductor/test_torchinductor.py', run_name='main')
  PY
• TORCHINDUCTOR_CPP_WRAPPER=1 python - <<'PY'
  import runpy
  import sys
  sys.modules['torchvision'] = None
  sys.path.insert(0, 'test/inductor')
  sys.argv = ['test/inductor/test_torchinductor.py', 'CpuTests.test_conv2d_backward_channels_last_cpu']
  runpy.run_path('test/inductor/test_torchinductor.py', run_name='main')
  PY
• python - <<'PY'
  import runpy
  import sys
  sys.modules['torchvision'] = None
  sys.path.insert(0, 'test/inductor')
  sys.argv = ['test/inductor/test_cpu_repro.py', 'CPUReproTests.test_require_stride_order_non_owning']
  runpy.run_path('test/inductor/test_cpu_repro.py', run_name='main')
  PY
• lintrunner -a

Pull Request resolved: #185145
Approved by: https://github.com/desertfire