[clang] [clang] Additional FP classification functions (PR #69041)

[Timm Baeder via cfe-commits]

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@@ -494,6 +494,9 @@ BUILTIN(__builtin_isinf,      "i.", "FnctE")
 BUILTIN(__builtin_isinf_sign, "i.", "FnctE")
 BUILTIN(__builtin_isnan,      "i.", "FnctE")
 BUILTIN(__builtin_isnormal,   "i.", "FnctE")
+BUILTIN(__builtin_issubnormal,"i.", "FnctE")
+BUILTIN(__builtin_iszero,     "i.", "FnctE")
+BUILTIN(__builtin_issignaling,"i.", "FnctE")
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tbaederr wrote:

The `E` means they can be evaluated at compile time, but I don't see changes to `ExprConstant.cpp`?

https://github.com/llvm/llvm-project/pull/69041