test/Transforms/PhaseOrdering/ptr-umax-null.ll

; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt -passes='default<O3>' -S < %s | FileCheck %s

target datalayout = "e-p:64:64"

; Commoning the null comparisons exposed by the pointer umax decomposition
; allows (X == null) || ((X == null) && (Y == null)) to simplify to X == null.
define i1 @umax_null_logical_or(ptr %x, ptr %y) {
; CHECK-LABEL: @umax_null_logical_or(
; CHECK-NEXT:    [[XNULL:%.*]] = icmp eq ptr [[X:%.*]], null
; CHECK-NEXT:    ret i1 [[XNULL]]
;
  %xnull = icmp eq ptr %x, null
  %cmp = icmp ugt ptr %x, %y
  %max = select i1 %cmp, ptr %x, ptr %y
  %maxnull = icmp eq ptr %max, null
  %r = select i1 %xnull, i1 true, i1 %maxnull
  ret i1 %r
}

; The order of the comparisons exposed by the decomposition does not matter.
define i1 @umax_null_logical_or_commuted(ptr %x, ptr %y) {
; CHECK-LABEL: @umax_null_logical_or_commuted(
; CHECK-NEXT:    [[XNULL:%.*]] = icmp eq ptr [[X:%.*]], null
; CHECK-NEXT:    ret i1 [[XNULL]]
;
  %xnull = icmp eq ptr %x, null
  %cmp = icmp ult ptr %y, %x
  %max = select i1 %cmp, ptr %x, ptr %y
  %maxnull = icmp eq ptr %max, null
  %r = select i1 %xnull, i1 true, i1 %maxnull
  ret i1 %r
}