[PATCH] D35295: [docs] Add section 'Half-Precision Floating Point'

[Simon Tatham via Phabricator via cfe-commits]

simon_tatham added inline comments.


================
Comment at: docs/LanguageExtensions.rst:448
+``__fp16`` is a storage and interchange format only. This means that values of
+``__fp16`` promote to (at least) float when used in artimethic operations. There are
+two ``__fp16`` formats. Clang supports the IEEE 754-2008 format and not the
----------------
typo: artimethic -> arithmetic


================
Comment at: docs/LanguageExtensions.rst:454
+``_FloatN`` is defined as a binary floating type, where the N suffix denotes
+the number of bits and is 16, 32, 64, or greater and egual to 128 and a
+multiple of 32. Clang supports ``_Float16``.  The difference with ``__fp16`` is
----------------
typo: egual -> equal


================
Comment at: docs/LanguageExtensions.rst:455
+the number of bits and is 16, 32, 64, or greater and egual to 128 and a
+multiple of 32. Clang supports ``_Float16``.  The difference with ``__fp16`` is
+that arithmetic is performed in half-precision, thus it is not a storage-only
----------------
Wording nit: "The difference with `__fp16` is that ..." suggests that you're about to describe how __fp16 does things. Or at least it could be read as suggesting that.

Using "from" instead of "with" clarifies that you're saying how something is //unlike// fp16. I think I would also clarify by restating the type name in the subclause, along the lines of

  The difference from ``__fp16`` is that arithmetic on ``_Float16`` is performed in half-precision, ...


https://reviews.llvm.org/D35295