[clang] [llvm] Option to control signaling NaN support (PR #193055)

[Serge Pavlov via cfe-commits]

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@@ -2574,6 +2574,14 @@ For example:
 ``sanitize_alloc_token``
     This attribute indicates that implicit allocation token instrumentation
     is enabled for this function.
+``signaling-nans``
+    If a function has this attribute, signaling NaNs are assumed to be treated
+    according to IEEE 754 rules. That is, signaling NaN values are quieted in
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spavloff wrote:

Multiplication by `1.0` can be used by a user as a portable way for quieting sNaNs. This operation does not access FP environment and should be available in default mode also.

https://github.com/llvm/llvm-project/pull/193055