[PATCH] D152351: [clang] Add __builtin_isfpclass

[Serge Pavlov via Phabricator via cfe-commits]

sepavloff added a comment.

In D152351#4402615 <https://reviews.llvm.org/D152351#4402615>, @qiucf wrote:

> It's necessary to check range of first argument in `SemaChecking.cpp` using `SemaBuiltinConstantArgRange`.
>
>   _Bool check_isfpclass_1(float x) { return __builtin_isfpclass(123456, x); } // ICE
>   
>   int g;
>   // error: cannot compile this builtin function yet
>   // there's better diagnostics when 1st argument is not constant
>   _Bool check_isfpclass_2(float x) { return __builtin_isfpclass(g, x); }

Added the check and a test for it. Thanks!



================
Comment at: clang/include/clang/Basic/Builtins.def:491
 BUILTIN(__builtin_isnormal,   "i.", "FnctE")
+BUILTIN(__builtin_isfpclass,  "iCi.", "nctE")
 
----------------
qiucf wrote:
> Why these intrinsics' type spec end with dot? I thought they are for vaargs.
It is a hack to have polymorphic builtin function. The argument `.` represents one argument but it can be of any type. So no need to have separate functions for every type.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D152351/new/

https://reviews.llvm.org/D152351