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; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -instcombine -S | FileCheck %s
target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"
define i8* @example(i8* dereferenceable(24) %x) {
; CHECK-LABEL: @example(
; CHECK-NEXT: [[X2:%.*]] = bitcast i8* [[X:%.*]] to {}**
; CHECK-NEXT: [[Y:%.*]] = load {}*, {}** [[X2]], align 8
; CHECK-NEXT: [[Y_IS_NULL:%.*]] = icmp ne {}* [[Y]], null
; CHECK-NEXT: call void @llvm.assume(i1 [[Y_IS_NULL]])
; CHECK-NEXT: ret i8* [[X]]
;
%x2 = bitcast i8* %x to {}**
%y = load {}*, {}** %x2, align 8
%y_is_null = icmp eq {}* %y, null
%x0 = getelementptr inbounds i8, i8* %x, i64 0
%res = select i1 %y_is_null, i8* null, i8* %x0
%nonnull = icmp ne i8* %res, null
call void @llvm.assume(i1 %nonnull)
ret i8* %res
}
; TODO: this should be folded to `ret i8* %x` as well.
define i8* @example2(i8* %x) {
; CHECK-LABEL: @example2(
; CHECK-NEXT: [[X2:%.*]] = bitcast i8* [[X:%.*]] to {}**
; CHECK-NEXT: [[Y:%.*]] = load {}*, {}** [[X2]], align 8
; CHECK-NEXT: [[Y_IS_NULL:%.*]] = icmp eq {}* [[Y]], null
; CHECK-NEXT: [[RES:%.*]] = select i1 [[Y_IS_NULL]], i8* null, i8* [[X]]
; CHECK-NEXT: [[NONNULL:%.*]] = icmp ne i8* [[RES]], null
; CHECK-NEXT: call void @llvm.assume(i1 [[NONNULL]])
; CHECK-NEXT: ret i8* [[RES]]
;
%x2 = bitcast i8* %x to {}**
%y = load {}*, {}** %x2, align 8
%y_is_null = icmp eq {}* %y, null
%x0 = getelementptr inbounds i8, i8* %x, i64 0
%res = select i1 %y_is_null, i8* null, i8* %x0
%nonnull = icmp ne i8* %res, null
call void @llvm.assume(i1 %nonnull)
ret i8* %res
}
declare void @llvm.assume(i1)
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