llvm/test/Analysis/ValueTracking/knownzero-shift.ll


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; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt -instsimplify -S < %s | FileCheck %s

define i1 @test(i8 %p, i8* %pq) {
; CHECK-LABEL: @test(
; CHECK-NEXT:    ret i1 false
;
  %q = load i8, i8* %pq, !range !0 ; %q is known nonzero; no known bits
  %1 = or i8 %p, 2                 ; %1[1] = 1
  %2 = and i8 %1, 254              ; %2[0] = 0, %2[1] = 1
  %A = lshr i8 %2, 1               ; We should know that %A is nonzero.
  %x = icmp eq i8 %A, 0
  ret i1 %x
}

!0 = !{ i8 1, i8 5 }