2014-06-11-SwitchDefaultUnreachableOpt.ll
670 Bytes
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; 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
}