[clang] [Headers][X86] Make brief descriptions briefer (PR #82422)

[Phoebe Wang via cfe-commits]

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@@ -2099,9 +2099,11 @@ static __inline__ __m128i __DEFAULT_FN_ATTRS _mm_add_epi64(__m128i __a,
 }
 
 /// Adds, with saturation, the corresponding elements of two 128-bit
-///    signed [16 x i8] vectors, saving each sum in the corresponding element of
-///    a 128-bit result vector of [16 x i8]. Positive sums greater than 0x7F are
-///    saturated to 0x7F. Negative sums less than 0x80 are saturated to 0x80.
+///    signed [16 x i8] vectors, saving each sum in the corresponding element
+///    of a 128-bit result vector of [16 x i8].
+///
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phoebewang wrote:

> Are you saying the detail about saturation belongs in the brief description?

Yes. I though otherwise the full description may turn into the second paragraph only. I'm not a doxygen user, so the explanation sounds good to me.

https://github.com/llvm/llvm-project/pull/82422