[clang] [CIR] Upstream support for FlattenCFG switch and SwitchFlatOp (PR #139154)

[Bruno Cardoso Lopes via cfe-commits]

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@@ -0,0 +1,68 @@
+// RUN: cir-opt %s | FileCheck %s
+!s32i = !cir.int<s, 32>
+
+cir.func @FlatSwitchWithoutDefault(%arg0: !s32i) {
+  cir.switch.flat %arg0 : !s32i, ^bb2 [
+    1: ^bb1
+  ]
+  ^bb1:
+    cir.br ^bb2
+  ^bb2:
+    cir.return
+}
+
+// CHECK: cir.switch.flat %arg0 : !s32i, ^bb2 [
+// CHECK-NEXT:  1: ^bb1
+// CHECK-NEXT: ]
+// CHECK-NEXT: ^bb1:
+// CHECK-NEXT:   cir.br ^bb2
+// CHECK-NEXT: ^bb2:
+//CHECK-NEXT:    cir.return
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bcardosolopes wrote:

Odd indentation compared with other check lines

https://github.com/llvm/llvm-project/pull/139154