unused-phis.ll
720 Bytes
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; RUN: opt < %s -lcssa -S | FileCheck %s
; RUN: opt < %s -passes=lcssa -S | FileCheck %s
; CHECK: exit1:
; CHECK: .lcssa =
; CHECK: exit2:
; CHECK: .lcssa1 =
; CHECK: exit3:
; CHECK-NOT: .lcssa
; Test to ensure that when there are multiple exit blocks, PHI nodes are
; only inserted by LCSSA when there is a use dominated by a given exit
; block.
declare void @printf(i32 %i)
define i32 @unused_phis() nounwind {
entry:
br label %loop
loop:
%i = phi i32 [0, %entry], [1, %then2]
br i1 undef, label %exit1, label %then1
then1:
br i1 undef, label %exit2, label %then2
then2:
br i1 undef, label %exit3, label %loop
exit1:
call void @printf(i32 %i)
ret i32 %i
exit2:
ret i32 %i
exit3:
ret i32 0
}