; NOTE: Assertions have been autogenerated by utils/update_test_checks.py ; RUN: opt < %s -passes=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)