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; RUN: opt -S -simplifycfg < %s | FileCheck %s
; We're sign extending an 8-bit value.
; The switch condition must be in the range [-128, 127], so any cases outside of that range must be dead.
; Only the first case has a non-zero weight, but that gets eliminated. Note
; that this shouldn't have been the case in the first place, but the test here
; ensures that all-zero branch weights are not attached causing problems downstream.
define i1 @repeated_signbits(i8 %condition) {
; CHECK-LABEL: @repeated_signbits(
; CHECK: switch i32
; CHECK-DAG: i32 -128, label %a
; CHECK-DAG: i32 -1, label %a
; CHECK-DAG: i32 0, label %a
; CHECK-DAG: i32 127, label %a
; CHECK-NEXT: ]
; CHECK-NOT: , !prof
;
entry:
%sext = sext i8 %condition to i32
switch i32 %sext, label %default [
i32 -2147483648, label %a
i32 -129, label %a
i32 -128, label %a
i32 -1, label %a
i32 0, label %a
i32 127, label %a
i32 128, label %a
i32 2147483647, label %a
], !prof !1
a:
ret i1 1
default:
ret i1 0
}
!1 = !{!"branch_weights", i32 0, i32 1, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0}
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