; NOTE: Assertions have been autogenerated by utils/update_test_checks.py ; RUN: opt -S -instcombine < %s | FileCheck %s ; If we have an smax feeding a signed or equality icmp that shares an ; operand with the smax, the compare should always be folded. ; Test all 4 foldable predicates (eq,ne,sgt,sle) * 4 commutation ; possibilities for each predicate. Note that folds to true/false ; (predicate = sge/slt) or folds to an existing instruction should be ; handled by InstSimplify. ; smax(X, Y) == X --> X >= Y define i1 @eq_smax1(i32 %x, i32 %y) { ; CHECK-LABEL: @eq_smax1( ; CHECK-NEXT: [[CMP2:%.*]] = icmp sge i32 %x, %y ; CHECK-NEXT: ret i1 [[CMP2]] ; %cmp1 = icmp sgt i32 %x, %y %sel = select i1 %cmp1, i32 %x, i32 %y %cmp2 = icmp eq i32 %sel, %x ret i1 %cmp2 } ; Commute max operands. define i1 @eq_smax2(i32 %x, i32 %y) { ; CHECK-LABEL: @eq_smax2( ; CHECK-NEXT: [[CMP2:%.*]] = icmp sge i32 %x, %y ; CHECK-NEXT: ret i1 [[CMP2]] ; %cmp1 = icmp sgt i32 %y, %x %sel = select i1 %cmp1, i32 %y, i32 %x %cmp2 = icmp eq i32 %sel, %x ret i1 %cmp2 } ; Disguise the icmp predicate by commuting the max op to the RHS. define i1 @eq_smax3(i32 %a, i32 %y) { ; CHECK-LABEL: @eq_smax3( ; CHECK-NEXT: [[X:%.*]] = add i32 %a, 3 ; CHECK-NEXT: [[CMP2:%.*]] = icmp sge i32 [[X]], %y ; CHECK-NEXT: ret i1 [[CMP2]] ; %x = add i32 %a, 3 ; thwart complexity-based canonicalization %cmp1 = icmp sgt i32 %x, %y %sel = select i1 %cmp1, i32 %x, i32 %y %cmp2 = icmp eq i32 %x, %sel ret i1 %cmp2 } ; Commute max operands. define i1 @eq_smax4(i32 %a, i32 %y) { ; CHECK-LABEL: @eq_smax4( ; CHECK-NEXT: [[X:%.*]] = add i32 %a, 3 ; CHECK-NEXT: [[CMP2:%.*]] = icmp sge i32 [[X]], %y ; CHECK-NEXT: ret i1 [[CMP2]] ; %x = add i32 %a, 3 ; thwart complexity-based canonicalization %cmp1 = icmp sgt i32 %y, %x %sel = select i1 %cmp1, i32 %y, i32 %x %cmp2 = icmp eq i32 %x, %sel ret i1 %cmp2 } ; smax(X, Y) <= X --> X >= Y define i1 @sle_smax1(i32 %x, i32 %y) { ; CHECK-LABEL: @sle_smax1( ; CHECK-NEXT: [[CMP2:%.*]] = icmp sge i32 %x, %y ; CHECK-NEXT: ret i1 [[CMP2]] ; %cmp1 = icmp sgt i32 %x, %y %sel = select i1 %cmp1, i32 %x, i32 %y %cmp2 = icmp sle i32 %sel, %x ret i1 %cmp2 } ; Commute max operands. define i1 @sle_smax2(i32 %x, i32 %y) { ; CHECK-LABEL: @sle_smax2( ; CHECK-NEXT: [[CMP2:%.*]] = icmp sge i32 %x, %y ; CHECK-NEXT: ret i1 [[CMP2]] ; %cmp1 = icmp sgt i32 %y, %x %sel = select i1 %cmp1, i32 %y, i32 %x %cmp2 = icmp sle i32 %sel, %x ret i1 %cmp2 } ; Disguise the icmp predicate by commuting the max op to the RHS. define i1 @sle_smax3(i32 %a, i32 %y) { ; CHECK-LABEL: @sle_smax3( ; CHECK-NEXT: [[X:%.*]] = add i32 %a, 3 ; CHECK-NEXT: [[CMP2:%.*]] = icmp sge i32 [[X]], %y ; CHECK-NEXT: ret i1 [[CMP2]] ; %x = add i32 %a, 3 ; thwart complexity-based canonicalization %cmp1 = icmp sgt i32 %x, %y %sel = select i1 %cmp1, i32 %x, i32 %y %cmp2 = icmp sge i32 %x, %sel ret i1 %cmp2 } ; Commute max operands. define i1 @sle_smax4(i32 %a, i32 %y) { ; CHECK-LABEL: @sle_smax4( ; CHECK-NEXT: [[X:%.*]] = add i32 %a, 3 ; CHECK-NEXT: [[CMP2:%.*]] = icmp sge i32 [[X]], %y ; CHECK-NEXT: ret i1 [[CMP2]] ; %x = add i32 %a, 3 ; thwart complexity-based canonicalization %cmp1 = icmp sgt i32 %y, %x %sel = select i1 %cmp1, i32 %y, i32 %x %cmp2 = icmp sge i32 %x, %sel ret i1 %cmp2 } ; smax(X, Y) != X --> X < Y define i1 @ne_smax1(i32 %x, i32 %y) { ; CHECK-LABEL: @ne_smax1( ; CHECK-NEXT: [[CMP2:%.*]] = icmp slt i32 %x, %y ; CHECK-NEXT: ret i1 [[CMP2]] ; %cmp1 = icmp sgt i32 %x, %y %sel = select i1 %cmp1, i32 %x, i32 %y %cmp2 = icmp ne i32 %sel, %x ret i1 %cmp2 } ; Commute max operands. define i1 @ne_smax2(i32 %x, i32 %y) { ; CHECK-LABEL: @ne_smax2( ; CHECK-NEXT: [[CMP1:%.*]] = icmp sgt i32 %y, %x ; CHECK-NEXT: ret i1 [[CMP1]] ; %cmp1 = icmp sgt i32 %y, %x %sel = select i1 %cmp1, i32 %y, i32 %x %cmp2 = icmp ne i32 %sel, %x ret i1 %cmp2 } ; Disguise the icmp predicate by commuting the max op to the RHS. define i1 @ne_smax3(i32 %a, i32 %y) { ; CHECK-LABEL: @ne_smax3( ; CHECK-NEXT: [[X:%.*]] = add i32 %a, 3 ; CHECK-NEXT: [[CMP2:%.*]] = icmp slt i32 [[X]], %y ; CHECK-NEXT: ret i1 [[CMP2]] ; %x = add i32 %a, 3 ; thwart complexity-based canonicalization %cmp1 = icmp sgt i32 %x, %y %sel = select i1 %cmp1, i32 %x, i32 %y %cmp2 = icmp ne i32 %x, %sel ret i1 %cmp2 } ; Commute max operands. define i1 @ne_smax4(i32 %a, i32 %y) { ; CHECK-LABEL: @ne_smax4( ; CHECK-NEXT: [[X:%.*]] = add i32 %a, 3 ; CHECK-NEXT: [[CMP1:%.*]] = icmp slt i32 [[X]], %y ; CHECK-NEXT: ret i1 [[CMP1]] ; %x = add i32 %a, 3 ; thwart complexity-based canonicalization %cmp1 = icmp sgt i32 %y, %x %sel = select i1 %cmp1, i32 %y, i32 %x %cmp2 = icmp ne i32 %x, %sel ret i1 %cmp2 } ; smax(X, Y) > X --> X < Y define i1 @sgt_smax1(i32 %x, i32 %y) { ; CHECK-LABEL: @sgt_smax1( ; CHECK-NEXT: [[CMP2:%.*]] = icmp slt i32 %x, %y ; CHECK-NEXT: ret i1 [[CMP2]] ; %cmp1 = icmp sgt i32 %x, %y %sel = select i1 %cmp1, i32 %x, i32 %y %cmp2 = icmp sgt i32 %sel, %x ret i1 %cmp2 } ; Commute max operands. define i1 @sgt_smax2(i32 %x, i32 %y) { ; CHECK-LABEL: @sgt_smax2( ; CHECK-NEXT: [[CMP1:%.*]] = icmp sgt i32 %y, %x ; CHECK-NEXT: ret i1 [[CMP1]] ; %cmp1 = icmp sgt i32 %y, %x %sel = select i1 %cmp1, i32 %y, i32 %x %cmp2 = icmp sgt i32 %sel, %x ret i1 %cmp2 } ; Disguise the icmp predicate by commuting the max op to the RHS. define i1 @sgt_smax3(i32 %a, i32 %y) { ; CHECK-LABEL: @sgt_smax3( ; CHECK-NEXT: [[X:%.*]] = add i32 %a, 3 ; CHECK-NEXT: [[CMP2:%.*]] = icmp slt i32 [[X]], %y ; CHECK-NEXT: ret i1 [[CMP2]] ; %x = add i32 %a, 3 ; thwart complexity-based canonicalization %cmp1 = icmp sgt i32 %x, %y %sel = select i1 %cmp1, i32 %x, i32 %y %cmp2 = icmp slt i32 %x, %sel ret i1 %cmp2 } ; Commute max operands. define i1 @sgt_smax4(i32 %a, i32 %y) { ; CHECK-LABEL: @sgt_smax4( ; CHECK-NEXT: [[X:%.*]] = add i32 %a, 3 ; CHECK-NEXT: [[CMP1:%.*]] = icmp slt i32 [[X]], %y ; CHECK-NEXT: ret i1 [[CMP1]] ; %x = add i32 %a, 3 ; thwart complexity-based canonicalization %cmp1 = icmp sgt i32 %y, %x %sel = select i1 %cmp1, i32 %y, i32 %x %cmp2 = icmp slt i32 %x, %sel ret i1 %cmp2 }