[clang] [X86][AVX10.2] Add comments for the avx10_2convertintrin.h file (PR #120766)

[Phoebe Wang via cfe-commits]

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@@ -24,567 +24,3243 @@
   __attribute__((__always_inline__, __nodebug__, __target__("avx10.2-256"),    \
                  __min_vector_width__(256)))
 
+/// Convert two 128-bit vectors, \a __A and \a __B, containing packed
+/// single-precision (32-bit) floating-point elements to a 128-bit vector
+/// containing FP16 elements.
+///
+/// \code{.operation}
+/// FOR i := 0 to 7
+/// 	IF i < 4
+/// 		dst.fp16[i] := convert_fp32_to_fp16(__B.fp32[i])
+/// 	ELSE
+/// 		dst.fp16[i] := convert_fp32_to_fp16(__A.fp32[i - 4])
+/// 	FI
+/// ENDFOR
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phoebewang wrote:

Missing `DEST[MAX:128] := 0`, the same for the rest.

https://github.com/llvm/llvm-project/pull/120766