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; RUN: opt < %s -simplifycfg -S | FileCheck %s
; int foo1_with_default(int a) {
; switch(a) {
; case 10:
; return 10;
; case 20:
; return 2;
; }
; return 4;
; }
define i32 @foo1_with_default(i32 %a) {
; CHECK-LABEL: @foo1_with_default
; CHECK: %switch.selectcmp = icmp eq i32 %a, 20
; CHECK-NEXT: %switch.select = select i1 %switch.selectcmp, i32 2, i32 4
; CHECK-NEXT: %switch.selectcmp1 = icmp eq i32 %a, 10
; CHECK-NEXT: %switch.select2 = select i1 %switch.selectcmp1, i32 10, i32 %switch.select
entry:
switch i32 %a, label %sw.epilog [
i32 10, label %sw.bb
i32 20, label %sw.bb1
]
sw.bb:
br label %return
sw.bb1:
br label %return
sw.epilog:
br label %return
return:
%retval.0 = phi i32 [ 4, %sw.epilog ], [ 2, %sw.bb1 ], [ 10, %sw.bb ]
ret i32 %retval.0
}
; int foo1_without_default(int a) {
; switch(a) {
; case 10:
; return 10;
; case 20:
; return 2;
; }
; __builtin_unreachable();
; }
define i32 @foo1_without_default(i32 %a) {
; CHECK-LABEL: @foo1_without_default
; CHECK: %switch.selectcmp = icmp eq i32 %a, 10
; CHECK-NEXT: %switch.select = select i1 %switch.selectcmp, i32 10, i32 2
; CHECK-NOT: %switch.selectcmp1
entry:
switch i32 %a, label %sw.epilog [
i32 10, label %sw.bb
i32 20, label %sw.bb1
]
sw.bb:
br label %return
sw.bb1:
br label %return
sw.epilog:
unreachable
return:
%retval.0 = phi i32 [ 2, %sw.bb1 ], [ 10, %sw.bb ]
ret i32 %retval.0
}
|
