; NOTE: Assertions have been autogenerated by utils/update_test_checks.py ; RUN: opt < %s -passes=instcombine -S | FileCheck %s declare void @llvm.assume(i1) declare i8 @gen8() declare void @use8(i8) define i1 @t0(i8 %base, i8 %offset) { ; CHECK-LABEL: @t0( ; CHECK-NEXT: [[CMP:%.*]] = icmp slt i8 [[OFFSET:%.*]], 0 ; CHECK-NEXT: call void @llvm.assume(i1 [[CMP]]) ; CHECK-NEXT: [[ADJUSTED:%.*]] = sub i8 [[BASE:%.*]], [[OFFSET]] ; CHECK-NEXT: call void @use8(i8 [[ADJUSTED]]) ; CHECK-NEXT: [[RES:%.*]] = icmp uge i8 [[BASE]], [[OFFSET]] ; CHECK-NEXT: ret i1 [[RES]] ; %cmp = icmp slt i8 %offset, 0 call void @llvm.assume(i1 %cmp) %adjusted = sub i8 %base, %offset call void @use8(i8 %adjusted) %res = icmp ult i8 %adjusted, %base ret i1 %res } define i1 @t1(i8 %base, i8 %offset) { ; CHECK-LABEL: @t1( ; CHECK-NEXT: [[CMP:%.*]] = icmp slt i8 [[OFFSET:%.*]], 0 ; CHECK-NEXT: call void @llvm.assume(i1 [[CMP]]) ; CHECK-NEXT: [[ADJUSTED:%.*]] = sub i8 [[BASE:%.*]], [[OFFSET]] ; CHECK-NEXT: call void @use8(i8 [[ADJUSTED]]) ; CHECK-NEXT: [[RES:%.*]] = icmp ult i8 [[BASE]], [[OFFSET]] ; CHECK-NEXT: ret i1 [[RES]] ; %cmp = icmp slt i8 %offset, 0 call void @llvm.assume(i1 %cmp) %adjusted = sub i8 %base, %offset call void @use8(i8 %adjusted) %res = icmp uge i8 %adjusted, %base ret i1 %res } define i1 @t2(i8 %offset) { ; CHECK-LABEL: @t2( ; CHECK-NEXT: [[CMP:%.*]] = icmp slt i8 [[OFFSET:%.*]], 0 ; CHECK-NEXT: call void @llvm.assume(i1 [[CMP]]) ; CHECK-NEXT: [[BASE:%.*]] = call i8 @gen8() ; CHECK-NEXT: [[ADJUSTED:%.*]] = sub i8 [[BASE]], [[OFFSET]] ; CHECK-NEXT: call void @use8(i8 [[ADJUSTED]]) ; CHECK-NEXT: [[RES:%.*]] = icmp uge i8 [[BASE]], [[OFFSET]] ; CHECK-NEXT: ret i1 [[RES]] ; %cmp = icmp slt i8 %offset, 0 call void @llvm.assume(i1 %cmp) %base = call i8 @gen8() %adjusted = sub i8 %base, %offset call void @use8(i8 %adjusted) %res = icmp ugt i8 %base, %adjusted ret i1 %res } define i1 @t3(i8 %offset) { ; CHECK-LABEL: @t3( ; CHECK-NEXT: [[CMP:%.*]] = icmp slt i8 [[OFFSET:%.*]], 0 ; CHECK-NEXT: call void @llvm.assume(i1 [[CMP]]) ; CHECK-NEXT: [[BASE:%.*]] = call i8 @gen8() ; CHECK-NEXT: [[ADJUSTED:%.*]] = sub i8 [[BASE]], [[OFFSET]] ; CHECK-NEXT: call void @use8(i8 [[ADJUSTED]]) ; CHECK-NEXT: [[RES:%.*]] = icmp ult i8 [[BASE]], [[OFFSET]] ; CHECK-NEXT: ret i1 [[RES]] ; %cmp = icmp slt i8 %offset, 0 call void @llvm.assume(i1 %cmp) %base = call i8 @gen8() %adjusted = sub i8 %base, %offset call void @use8(i8 %adjusted) %res = icmp ule i8 %base, %adjusted ret i1 %res } ; Here we don't know that offset is non-zero. Can't fold. define i1 @n4_maybezero(i8 %base, i8 %offset) { ; CHECK-LABEL: @n4_maybezero( ; CHECK-NEXT: [[ADJUSTED:%.*]] = sub i8 [[BASE:%.*]], [[OFFSET:%.*]] ; CHECK-NEXT: call void @use8(i8 [[ADJUSTED]]) ; CHECK-NEXT: [[RES:%.*]] = icmp ult i8 [[ADJUSTED]], [[BASE]] ; CHECK-NEXT: ret i1 [[RES]] ; %adjusted = sub i8 %base, %offset call void @use8(i8 %adjusted) %res = icmp ult i8 %adjusted, %base ret i1 %res } ; We need to know that about %offset, %base won't do. Can't fold. define i1 @n5_wrongnonzero(i8 %base, i8 %offset) { ; CHECK-LABEL: @n5_wrongnonzero( ; CHECK-NEXT: [[CMP:%.*]] = icmp sgt i8 [[BASE:%.*]], 0 ; CHECK-NEXT: call void @llvm.assume(i1 [[CMP]]) ; CHECK-NEXT: [[ADJUSTED:%.*]] = sub i8 [[BASE]], [[OFFSET:%.*]] ; CHECK-NEXT: call void @use8(i8 [[ADJUSTED]]) ; CHECK-NEXT: [[RES:%.*]] = icmp ult i8 [[ADJUSTED]], [[BASE]] ; CHECK-NEXT: ret i1 [[RES]] ; %cmp = icmp sgt i8 %base, 0 call void @llvm.assume(i1 %cmp) %adjusted = sub i8 %base, %offset call void @use8(i8 %adjusted) %res = icmp ult i8 %adjusted, %base ret i1 %res }