[libc] [llvm] [libc][fenv] Refactor x86 fenv implementations to make it work for various fenv_t. (PR #165015)

[via llvm-commits]

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@@ -130,5 +130,11 @@
       "value": true,
       "doc": "Add nullptr checks in the library's implementations to some functions for which passing nullptr is undefined behavior."
     }
+  },
+  "fenv": {
+    "LIBC_CONF_TRAP_ON_RAISE_FP_EXCEPT": {
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lntue wrote:

Due to the significant runtime cost that we observed for this behavior, I think this should be off by default to benefits most users.

https://github.com/llvm/llvm-project/pull/165015