[PATCH] D67552: [LangRef] Clarify fmuladd(a, b, c) can be treated as fadd (fmul a, b), c).

[Florian Hahn via Phabricator via llvm-commits]

fhahn marked 2 inline comments as done.
fhahn added inline comments.


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Comment at: llvm/docs/LangRef.rst:13954
 
 is equivalent to the expression a \* b + c, except that rounding will
 not be performed between the multiplication and addition steps if the
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reames wrote:
> Please change:
> "is equivalent to the expression a \* b + c, except that rounding will
> not be performed between the multiplication and addition steps if the
> code generator fuses the operations. "
> 
> To:
> "is equivalent to the expression a \* b + c, except that it is unspecified whether rounding will be performed between the multiplication and addition steps. "
Sounds good, thanks! Do you think that clarification is enough, without the additional sentence?


================
Comment at: llvm/docs/LangRef.rst:13956
 not be performed between the multiplication and addition steps if the
-code generator fuses the operations. Fusion is not guaranteed, even if
-the target platform supports it. If a fused multiply-add is required, the
-corresponding :ref:`llvm.fma <int_fma>` intrinsic function should be used
-instead. This never sets errno, just as '``llvm.fma.*``'.
+code generator fuses the operations. The optimizer can treat `@llvm.fmuladd`
+as `fadd (fmul %a, %b), %c`, until the code generator replaces it with
----------------
reames wrote:
> Your added sentence does not parse for me.
Do you mean when reading the sentence or with sphinx?


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