More overflow checks in memory allocator.

[shoumikhin]

Summary:

• Safer overflow math for high alignments
• Only over-allocate up to alignment - 1 bytes when a higher-than-malloc alignment is requested
• Move EXECUTORCH_TRACK_ALLOCATION to after a successful allocation and use the final size

Differential Revision: D86228757

[pytorch-bot]

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✅ You can merge normally! (6 Unrelated Failures)

As of commit c325d75 with merge base 149e23d ():

BROKEN TRUNK - The following jobs failed but were present on the merge base:

👉 Rebase onto the `viable/strict` branch to avoid these failures

• pull / test-binary-size-linux-gcc / linux-job (gh) (trunk failure)
  ##[error]The operation was canceled.
• pull / test-openvino-linux / linux-job (gh) (trunk failure)
  ##[error]The operation was canceled.
• pull / test-setup-linux-gcc / linux-job (gh) (trunk failure)
  ##[error]The operation was canceled.
• pull / unittest / windows / windows-job (gh) (trunk failure)
  backends/xnnpack/test/ops/test_conv1d.py::TestConv1d::test_qs8_conv1d_batchnorm_seq
• pull / unittest-editable / windows / windows-job (gh) (trunk failure)
  backends/xnnpack/test/ops/test_conv1d.py::TestConv1d::test_qs8_conv1d_batchnorm_seq
• trunk / unittest-release / windows / windows-job (gh) (trunk failure)
  backends/xnnpack/test/ops/test_conv1d.py::TestConv1d::test_qs8_conv1d_batchnorm_seq

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[meta-codesync]

@shoumikhin has exported this pull request. If you are a Meta employee, you can view the originating Diff in D86228757.

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