[clang] [CIR] Upstream a batch of passing tests from CIR-Incubator (PR #157333)

[Andy Kaylor via cfe-commits]

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@@ -0,0 +1,42 @@
+// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -fclangir -emit-cir %s -o %t.cir
+// RUN: FileCheck --input-file=%t.cir %s
+
+// Yields void.
+void test1() { ({ }); }
+// CHECK: @test1
+//     CHECK-NEXT: cir.return
+
+
+// Yields an out-of-scope scalar.
+void test2() { ({int x = 3; x; }); }
+// CHECK: @test2
+// CHECK: %[[#RETVAL:]] = cir.alloca !s32i, !cir.ptr<!s32i>
+// CHECK: cir.scope {
+// CHECK:   %[[#VAR:]] = cir.alloca !s32i, !cir.ptr<!s32i>, ["x", init]
+//          [...]
+// CHECK:   %[[#TMP:]] = cir.load{{.*}} %[[#VAR]] : !cir.ptr<!s32i>, !s32i
+// CHECK:   cir.store{{.*}} %[[#TMP]], %[[#RETVAL]] : !s32i, !cir.ptr<!s32i>
+// CHECK: }
+// CHECK: %{{.+}} = cir.load{{.*}} %[[#RETVAL]] : !cir.ptr<!s32i>, !s32i
+
+// Yields an aggregate.
+struct S { int x; };
+int test3() { return ({ struct S s = {1}; s; }).x; }
+// CHECK: @test3
+// CHECK: cir.scope {
+// CHECK: %[[#REF_TMP:]] = cir.alloca !rec_S, !cir.ptr<!rec_S>, ["ref.tmp0"]
+// CHECK:   cir.scope {
+// CHECK:     %[[#VAR:]] = cir.alloca !rec_S, !cir.ptr<!rec_S>
+//            [...]
+// CHECK:     cir.copy %[[#VAR]] to %[[#REF_TMP]] : !cir.ptr<!rec_S>
+// CHECK:   }
+// CHECK: %[[#RETADDR:]] = cir.get_member %[[#REF_TMP]][0] {name = "x"} : !cir.ptr<!rec_S> -> !cir.ptr<!s32i>
+// CHECK: %{{.+}} = cir.load{{.*}} %[[#RETADDR]] : !cir.ptr<!s32i>, !s32i
+
+// Expression is wrapped in an expression attribute (just ensure it does not crash).
+void test4(int x) { ({[[gsl::suppress("foo")]] x;}); }
+// CHECK: @test4
+
+// TODO(cir): Missing label support.
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andykaylor wrote:

@Andres-Salamanca Can we add a proper test for this now?

https://github.com/llvm/llvm-project/pull/157333