[compiler-rt] [builtins][AArch32] Fix __gnu_* functions (PR #137638)

[Peter Smith via llvm-commits]

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@@ -16,12 +16,12 @@ COMPILER_RT_ABI NOINLINE float __extendhfsf2(src_t a) {
   return __extendXfYf2__(a);
 }
 
-COMPILER_RT_ABI float __gnu_h2f_ieee(src_t a) { return __extendhfsf2(a); }
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smithp35 wrote:

This is the default for all non-Arm targets, as written this will disappear from all but the `__ARM_EABI__` targets.

This is probably fine in practice as at least recent versions of clang will not call `__gnu_h2f_ieee` and `__gnu_f2h_ieee` for non Arm targets. It will be worth a #else for #if defined(`__ARM_EABI__`) with this line just in case a new compiler-rt is used with an old object with such a call.

https://github.com/llvm/llvm-project/pull/137638