Imported Upstream version 5.18.0.225

Former-commit-id: 10196d987d5fc5564b9d3b33b1fdf13190f4d0b5

external/llvm/test/Transforms/LowerSwitch/2014-06-11-SwitchDefaultUnreachableOpt.ll

@@ -0,0 +1,44 @@
+; RUN: opt < %s -lowerswitch -S | FileCheck %s
+;
+; The switch is lowered with a single icmp.
+; CHECK: icmp
+; CHECK-NOT: icmp
+;
+;int foo(int a) {
+;
+;  switch (a) {
+;  case 0:
+;    return 10;
+;  case 1:
+;    return 3;
+;  default:
+;    __builtin_unreachable();
+;  }
+;
+;}
+
+define i32 @foo(i32 %a) {
+  %1 = alloca i32, align 4
+  %2 = alloca i32, align 4
+  store i32 %a, i32* %2, align 4
+  %3 = load i32, i32* %2, align 4
+  switch i32 %3, label %6 [
+    i32 0, label %4
+    i32 1, label %5
+  ]
+
+; <label>:4 
+  store i32 10, i32* %1
+  br label %7
+
+; <label>:5
+  store i32 3, i32* %1
+  br label %7
+
+; <label>:6
+  unreachable
+
+; <label>:7
+  %8 = load i32, i32* %1
+  ret i32 %8
+}