[clang] [CIR] Upstream minimal builtin function call support (PR #142981)

[Erich Keane via cfe-commits]

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@@ -0,0 +1,30 @@
+// RUN: %clang_cc1 -std=c++11 -triple x86_64-unknown-linux-gnu -Wno-unused-value -fclangir -emit-cir %s -o %t.cir
+// RUN: FileCheck --input-file=%t.cir %s -check-prefix=CIR
+// RUN: %clang_cc1 -std=c++11 -triple x86_64-unknown-linux-gnu -Wno-unused-value -fclangir -emit-llvm %s -o %t-cir.ll
+// RUN: FileCheck --input-file=%t-cir.ll %s -check-prefix=LLVM
+// RUN: %clang_cc1 -std=c++11 -triple x86_64-unknown-linux-gnu -Wno-unused-value -emit-llvm %s -o %t.ll
+// RUN: FileCheck --input-file=%t.ll %s -check-prefix=OGCG
+
+constexpr extern int cx_var = __builtin_is_constant_evaluated();
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erichkeane wrote:

We still seem to have a lot of code not tested in here?  I don't see any FP stuff here, for example.

https://github.com/llvm/llvm-project/pull/142981