Add regression test for <#288>

Author: GuillaumeGomez

tests/run/call-llvm-intrinsics.rs

@@ -0,0 +1,38 @@
+// Compiler:
+//
+// Run-time:
+//   status: 0
+
+// FIXME: Remove this test once rustc's `./tests/codegen/riscv-abi/call-llvm-intrinsics.rs`
+// stops ignoring GCC backend.
+
+#![feature(link_llvm_intrinsics)]
+#![allow(internal_features)]
+
+struct A;
+
+impl Drop for A {
+    fn drop(&mut self) {
+        println!("A");
+    }
+}
+
+extern "C" {
+    #[link_name = "llvm.sqrt.f32"]
+    fn sqrt(x: f32) -> f32;
+}
+
+pub fn do_call() {
+    let _a = A;
+
+    unsafe {
+        // Ensure that we `call` LLVM intrinsics instead of trying to `invoke` them
+        // CHECK: store float 4.000000e+00, float* %{{.}}, align 4
+        // CHECK: call float @llvm.sqrt.f32(float %{{.}}
+        sqrt(4.0);
+    }
+}
+
+fn main() {
+    do_call();
+}