xref: /aosp_15_r20/external/llvm/test/Transforms/LowerSwitch/2014-06-11-SwitchDefaultUnreachableOpt.ll (revision 9880d6810fe72a1726cb53787c6711e909410d58) 
1*9880d681SAndroid Build Coastguard Worker; RUN: opt < %s -lowerswitch -S | FileCheck %s
2*9880d681SAndroid Build Coastguard Worker;
3*9880d681SAndroid Build Coastguard Worker; The switch is lowered with a single icmp.
4*9880d681SAndroid Build Coastguard Worker; CHECK: icmp
5*9880d681SAndroid Build Coastguard Worker; CHECK-NOT: icmp
6*9880d681SAndroid Build Coastguard Worker;
7*9880d681SAndroid Build Coastguard Worker;int foo(int a) {
8*9880d681SAndroid Build Coastguard Worker;
9*9880d681SAndroid Build Coastguard Worker;  switch (a) {
10*9880d681SAndroid Build Coastguard Worker;  case 0:
11*9880d681SAndroid Build Coastguard Worker;    return 10;
12*9880d681SAndroid Build Coastguard Worker;  case 1:
13*9880d681SAndroid Build Coastguard Worker;    return 3;
14*9880d681SAndroid Build Coastguard Worker;  default:
15*9880d681SAndroid Build Coastguard Worker;    __builtin_unreachable();
16*9880d681SAndroid Build Coastguard Worker;  }
17*9880d681SAndroid Build Coastguard Worker;
18*9880d681SAndroid Build Coastguard Worker;}
19*9880d681SAndroid Build Coastguard Worker
20*9880d681SAndroid Build Coastguard Workerdefine i32 @foo(i32 %a) {
21*9880d681SAndroid Build Coastguard Worker  %1 = alloca i32, align 4
22*9880d681SAndroid Build Coastguard Worker  %2 = alloca i32, align 4
23*9880d681SAndroid Build Coastguard Worker  store i32 %a, i32* %2, align 4
24*9880d681SAndroid Build Coastguard Worker  %3 = load i32, i32* %2, align 4
25*9880d681SAndroid Build Coastguard Worker  switch i32 %3, label %6 [
26*9880d681SAndroid Build Coastguard Worker    i32 0, label %4
27*9880d681SAndroid Build Coastguard Worker    i32 1, label %5
28*9880d681SAndroid Build Coastguard Worker  ]
29*9880d681SAndroid Build Coastguard Worker
30*9880d681SAndroid Build Coastguard Worker; <label>:4
31*9880d681SAndroid Build Coastguard Worker  store i32 10, i32* %1
32*9880d681SAndroid Build Coastguard Worker  br label %7
33*9880d681SAndroid Build Coastguard Worker
34*9880d681SAndroid Build Coastguard Worker; <label>:5
35*9880d681SAndroid Build Coastguard Worker  store i32 3, i32* %1
36*9880d681SAndroid Build Coastguard Worker  br label %7
37*9880d681SAndroid Build Coastguard Worker
38*9880d681SAndroid Build Coastguard Worker; <label>:6
39*9880d681SAndroid Build Coastguard Worker  unreachable
40*9880d681SAndroid Build Coastguard Worker
41*9880d681SAndroid Build Coastguard Worker; <label>:7
42*9880d681SAndroid Build Coastguard Worker  %8 = load i32, i32* %1
43*9880d681SAndroid Build Coastguard Worker  ret i32 %8
44*9880d681SAndroid Build Coastguard Worker}
45