; RUN: opt -S -passes=instcombine,simplify-cfg < %s 2>&1 | FileCheck %s declare void @llvm.assume(i1 noundef) define void @f1(i8* %a) { ; CHECK-LABEL: @f1( ; CHECK-NEXT: entry: ; CHECK-NEXT: [[PTR:%.*]] = getelementptr inbounds i8, i8* [[A:%.*]], i64 4 ; CHECK-NEXT: [[TMP0:%.*]] = ptrtoint i8* [[PTR]] to i64 ; CHECK-NEXT: [[TMP1:%.*]] = and i64 [[TMP0]], 3 ; CHECK-NEXT: [[TMP2:%.*]] = icmp eq i64 [[TMP1]], 0 ; CHECK-NEXT: br i1 [[TMP2]], label [[IF_THEN:%.*]], label [[IF_END:%.*]] ; CHECK: if.then: ; CHECK-NEXT: call void @llvm.assume(i1 true) [ "align"(i8* [[PTR]], i64 4) ] ; CHECK-NEXT: [[TMP3:%.*]] = bitcast i8* [[PTR]] to i32* ; CHECK-NEXT: store i32 4, i32* [[TMP3]], align 4 ; CHECK-NEXT: br label [[IF_END]] ; CHECK: if.end: ; CHECK-NEXT: ret void ; entry: %ptr = getelementptr inbounds i8, i8* %a, i64 4 %0 = ptrtoint i8* %ptr to i64 %1 = and i64 %0, 3 %2 = icmp eq i64 %1, 0 br i1 %2, label %if.then, label %if.end if.then: ; preds = %entry call void @llvm.assume(i1 true) [ "align"(i8* %ptr, i64 4) ] %3 = ptrtoint i8* %ptr to i64 %4 = and i64 %3, 3 %5 = icmp eq i64 %4, 0 br i1 %5, label %if.then1, label %if.else1 if.then1: ; preds = %if.then %6 = bitcast i8* %ptr to i32* store i32 4, i32* %6, align 4 br label %if.end if.else1: ; preds = %if.then store i8 1, i8* %ptr, align 1 br label %if.end if.end: ; preds = %if.then1, %if.else1, %entry ret void } ; TODO: We could fold away the branch "br i1 %3, ..." by either using a GEP or make getKnowledgeValidInContext aware the alignment bundle offset, and the improvement of value tracking of GEP. define void @f2(i8* %a) { ; CHECK-LABEL: @f2( ; CHECK-NEXT: entry: ; CHECK-NEXT: call void @llvm.assume(i1 true) [ "align"(i8* [[A:%.*]], i64 32, i32 24) ] ; CHECK-NEXT: [[TMP0:%.*]] = getelementptr inbounds i8, i8* [[A]], i64 8 ; CHECK-NEXT: [[TMP1:%.*]] = ptrtoint i8* [[TMP0]] to i64 ; CHECK-NEXT: [[TMP2:%.*]] = and i64 [[TMP1]], 8 ; CHECK-NEXT: [[TMP3:%.*]] = icmp eq i64 [[TMP2]], 0 ; CHECK-NEXT: br i1 [[TMP3]], label [[IF_THEN1:%.*]], label [[IF_ELSE1:%.*]] ; entry: call void @llvm.assume(i1 true) [ "align"(i8* %a, i64 32, i32 24) ] %0 = getelementptr inbounds i8, i8* %a, i64 8 %1 = ptrtoint i8* %0 to i64 %2 = and i64 %1, 15 %3 = icmp eq i64 %2, 0 br i1 %3, label %if.then, label %if.else if.then: ; preds = %entry %4 = bitcast i8* %0 to i64* store i64 16, i64* %4, align 4 br label %if.end if.else: ; preds = %entry store i8 1, i8* %0, align 1 br label %if.end if.end: ; preds = %if.else, %if.then ret void }