File: redundant-left-shift-input-masking-pr49778.ll

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llvm-toolchain-19 1%3A19.1.7-3
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; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -passes=instcombine -S | FileCheck %s

; PR49778: this should not be folded to 0.
define i32 @src(i1 %x2) {
; CHECK-LABEL: @src(
; CHECK-NEXT:    [[X13:%.*]] = zext i1 [[X2:%.*]] to i32
; CHECK-NEXT:    [[_7:%.*]] = shl nsw i32 -1, [[X13]]
; CHECK-NEXT:    [[MASK:%.*]] = xor i32 [[_7]], -1
; CHECK-NEXT:    [[_8:%.*]] = and i32 [[MASK]], [[X13]]
; CHECK-NEXT:    [[_9:%.*]] = shl nuw nsw i32 [[_8]], [[X13]]
; CHECK-NEXT:    ret i32 [[_9]]
;
  %x13 = zext i1 %x2 to i32
  %_7 = shl i32 4294967295, %x13
  %mask = xor i32 %_7, 4294967295
  %_8 = and i32 %mask, %x13
  %_9 = shl i32 %_8, %x13
  ret i32 %_9
}