llvm-project/llvm/test/Transforms/LowerSwitch/condition-phi-unreachable-d...

37 lines
1.0 KiB
LLVM

; RUN: opt < %s -lowerswitch -S | FileCheck %s
; This test verifies -lowerswitch does not crash when an removing an
; unreachable default branch causes a PHI node used as the switch
; condition to be erased.
define void @f() local_unnamed_addr {
entry:
br label %sw.epilog
sw.epilog: ; preds = %sw.epilog.outer, %for.body
%i = phi i32 [ undef, %for.body ], [ 0, %entry ]
br i1 undef, label %for.body, label %for.end
for.body: ; preds = %sw.epilog
switch i32 %i, label %sw.epilog [
i32 0, label %sw.epilog.outer.backedge.loopexit
i32 1, label %sw.epilog.outer.backedge
]
sw.epilog.outer.backedge.loopexit: ; preds = %for.body
br label %for.end
sw.epilog.outer.backedge: ; preds = %for.body
unreachable
for.end: ; preds = %sw.epilog
ret void
}
; The phi and the switch should both be eliminated.
; CHECK: @f()
; CHECK: sw.epilog:
; CHECK-NOT: phi
; CHECK: for.body:
; CHECK-NOT: switch