[clang] [Clang] Add constexpr eval for cmath builtins (PR #194327)

[Zahira Ammarguellat via cfe-commits]

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@@ -6,17 +6,18 @@
 // RUN: %clang_cc1 -triple powerpc-ibm-aix -mlong-double-64 -emit-llvm -o - %s | FileCheck -check-prefix=CHECK %s
 // RUN: %clang_cc1 -triple powerpc64-ibm-aix -mlong-double-64 -emit-llvm -o - %s | FileCheck -check-prefix=CHECK %s
 
+long double arg = 1.0L;
 int main()
 {
   int DummyInt;
   long double DummyLongDouble;
   long double returnValue;
 
-  returnValue = __builtin_modfl(1.0L, &DummyLongDouble);
-  returnValue = __builtin_frexpl(0.0L, &DummyInt);
-  returnValue = __builtin_ldexpl(1.0L, 1);
+  returnValue = __builtin_modfl(arg, &DummyLongDouble);
+  returnValue = __builtin_frexpl(arg, &DummyInt);
+  returnValue = __builtin_ldexpl(arg, 1);
 }
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zahiraam wrote:

Good point!

https://github.com/llvm/llvm-project/pull/194327