llvm-project/llvm/test/Transforms/JumpThreading/degenerate-phi.ll

25 lines
550 B
LLVM

; RUN: opt -jump-threading -disable-output < %s
; PR9112
; This is actually a test for value tracking. Jump threading produces
; "%phi = phi i16" when it removes all edges leading to %unreachable.
; The .ll parser won't let us write that directly since it's invalid code.
define void @func() nounwind {
entry:
br label %bb
bb:
br label %bb
unreachable:
%phi = phi i16 [ %add, %unreachable ], [ 0, %next ]
%add = add i16 0, %phi
%cmp = icmp slt i16 %phi, 0
br i1 %cmp, label %unreachable, label %next
next:
br label %unreachable
}