Merge pull request #4884 from vitong/main

Update doc with cl.exe /arm64EC flag

Author: prmerger-automator[bot]

docs/build/reference/compiler-options-listed-alphabetically.md

@@ -17,6 +17,7 @@ This table contains an alphabetical list of compiler options. For a list of comp
 | [`/AI<dir>`](ai-specify-metadata-directories.md) | Specifies a directory to search to resolve file references passed to the [`#using`](../../preprocessor/hash-using-directive-cpp.md) directive. |
 | [`/analyze`](analyze-code-analysis.md) | Enables code analysis. |
 | [`/arch:<IA32|SSE|SSE2|AVX|AVX2|AVX512>`](arch-x86.md) | Minimum CPU architecture requirements. IA32, SSE, and SSE2 are x86 only. |
+| `/arm64EC` | Generate code compatible with the arm64EC ABI. |
 | [`/await`](await-enable-coroutine-support.md) | Enable coroutines (resumable functions) extensions. |
 | [`/await:strict`](await-enable-coroutine-support.md) | Enable standard C++20 coroutine support with earlier language versions. |
 | [`/bigobj`](bigobj-increase-number-of-sections-in-dot-obj-file.md) | Increases the number of addressable sections in an .obj file. |