llvm/test/Transforms/InstCombine/smin-icmp.ll

; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt -S -instcombine < %s | FileCheck %s

; If we have an smin feeding a signed or equality icmp that shares an
; operand with the smin, the compare should always be folded.
; Test all 6 foldable predicates (eq,ne,sge,sgt,sle,slt) * 4 commutation
; possibilities for each predicate. Note that folds to true/false or
; folds to an existing instruction may be handled by InstSimplify.

; smin(X, Y) == X --> X <= Y

define i1 @eq_smin1(i32 %x, i32 %y) {
; CHECK-LABEL: @eq_smin1(
; CHECK-NEXT:    [[CMP2:%.*]] = icmp sle i32 %x, %y
; CHECK-NEXT:    ret i1 [[CMP2]]
;
  %cmp1 = icmp slt i32 %x, %y
  %sel = select i1 %cmp1, i32 %x, i32 %y
  %cmp2 = icmp eq i32 %sel, %x
  ret i1 %cmp2
}

; Commute min operands.

define i1 @eq_smin2(i32 %x, i32 %y) {
; CHECK-LABEL: @eq_smin2(
; CHECK-NEXT:    [[CMP2:%.*]] = icmp sle i32 %x, %y
; CHECK-NEXT:    ret i1 [[CMP2]]
;
  %cmp1 = icmp slt 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 min op to the RHS.

define i1 @eq_smin3(i32 %a, i32 %y) {
; CHECK-LABEL: @eq_smin3(
; CHECK-NEXT:    [[X:%.*]] = add i32 %a, 3
; CHECK-NEXT:    [[CMP2:%.*]] = icmp sle i32 [[X]], %y
; CHECK-NEXT:    ret i1 [[CMP2]]
;
  %x = add i32 %a, 3 ; thwart complexity-based canonicalization
  %cmp1 = icmp slt i32 %x, %y
  %sel = select i1 %cmp1, i32 %x, i32 %y
  %cmp2 = icmp eq i32 %x, %sel
  ret i1 %cmp2
}

; Commute min operands.

define i1 @eq_smin4(i32 %a, i32 %y) {
; CHECK-LABEL: @eq_smin4(
; CHECK-NEXT:    [[X:%.*]] = add i32 %a, 3
; CHECK-NEXT:    [[CMP2:%.*]] = icmp sle i32 [[X]], %y
; CHECK-NEXT:    ret i1 [[CMP2]]
;
  %x = add i32 %a, 3 ; thwart complexity-based canonicalization
  %cmp1 = icmp slt i32 %y, %x
  %sel = select i1 %cmp1, i32 %y, i32 %x
  %cmp2 = icmp eq i32 %x, %sel
  ret i1 %cmp2
}

; smin(X, Y) >= X --> X <= Y

define i1 @sge_smin1(i32 %x, i32 %y) {
; CHECK-LABEL: @sge_smin1(
; CHECK-NEXT:    [[CMP2:%.*]] = icmp sle i32 %x, %y
; CHECK-NEXT:    ret i1 [[CMP2]]
;
  %cmp1 = icmp slt i32 %x, %y
  %sel = select i1 %cmp1, i32 %x, i32 %y
  %cmp2 = icmp sge i32 %sel, %x
  ret i1 %cmp2
}

; Commute min operands.

define i1 @sge_smin2(i32 %x, i32 %y) {
; CHECK-LABEL: @sge_smin2(
; CHECK-NEXT:    [[CMP2:%.*]] = icmp sle i32 %x, %y
; CHECK-NEXT:    ret i1 [[CMP2]]
;
  %cmp1 = icmp slt i32 %y, %x
  %sel = select i1 %cmp1, i32 %y, i32 %x
  %cmp2 = icmp sge i32 %sel, %x
  ret i1 %cmp2
}

; Disguise the icmp predicate by commuting the min op to the RHS.

define i1 @sge_smin3(i32 %a, i32 %y) {
; CHECK-LABEL: @sge_smin3(
; CHECK-NEXT:    [[X:%.*]] = add i32 %a, 3
; CHECK-NEXT:    [[CMP2:%.*]] = icmp sle i32 [[X]], %y
; CHECK-NEXT:    ret i1 [[CMP2]]
;
  %x = add i32 %a, 3 ; thwart complexity-based canonicalization
  %cmp1 = icmp slt i32 %x, %y
  %sel = select i1 %cmp1, i32 %x, i32 %y
  %cmp2 = icmp sle i32 %x, %sel
  ret i1 %cmp2
}

; Commute min operands.

define i1 @sge_smin4(i32 %a, i32 %y) {
; CHECK-LABEL: @sge_smin4(
; CHECK-NEXT:    [[X:%.*]] = add i32 %a, 3
; CHECK-NEXT:    [[CMP2:%.*]] = icmp sle i32 [[X]], %y
; CHECK-NEXT:    ret i1 [[CMP2]]
;
  %x = add i32 %a, 3 ; thwart complexity-based canonicalization
  %cmp1 = icmp slt i32 %y, %x
  %sel = select i1 %cmp1, i32 %y, i32 %x
  %cmp2 = icmp sle i32 %x, %sel
  ret i1 %cmp2
}

; smin(X, Y) != X --> X > Y

define i1 @ne_smin1(i32 %x, i32 %y) {
; CHECK-LABEL: @ne_smin1(
; CHECK-NEXT:    [[CMP2:%.*]] = icmp sgt i32 %x, %y
; CHECK-NEXT:    ret i1 [[CMP2]]
;
  %cmp1 = icmp slt i32 %x, %y
  %sel = select i1 %cmp1, i32 %x, i32 %y
  %cmp2 = icmp ne i32 %sel, %x
  ret i1 %cmp2
}

; Commute min operands.

define i1 @ne_smin2(i32 %x, i32 %y) {
; CHECK-LABEL: @ne_smin2(
; CHECK-NEXT:    [[CMP1:%.*]] = icmp slt i32 %y, %x
; CHECK-NEXT:    ret i1 [[CMP1]]
;
  %cmp1 = icmp slt 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 min op to the RHS.

define i1 @ne_smin3(i32 %a, i32 %y) {
; CHECK-LABEL: @ne_smin3(
; CHECK-NEXT:    [[X:%.*]] = add i32 %a, 3
; CHECK-NEXT:    [[CMP2:%.*]] = icmp sgt i32 [[X]], %y
; CHECK-NEXT:    ret i1 [[CMP2]]
;
  %x = add i32 %a, 3 ; thwart complexity-based canonicalization
  %cmp1 = icmp slt i32 %x, %y
  %sel = select i1 %cmp1, i32 %x, i32 %y
  %cmp2 = icmp ne i32 %x, %sel
  ret i1 %cmp2
}

; Commute min operands.

define i1 @ne_smin4(i32 %a, i32 %y) {
; CHECK-LABEL: @ne_smin4(
; CHECK-NEXT:    [[X:%.*]] = add i32 %a, 3
; CHECK-NEXT:    [[CMP1:%.*]] = icmp sgt i32 [[X]], %y
; CHECK-NEXT:    ret i1 [[CMP1]]
;
  %x = add i32 %a, 3 ; thwart complexity-based canonicalization
  %cmp1 = icmp slt i32 %y, %x
  %sel = select i1 %cmp1, i32 %y, i32 %x
  %cmp2 = icmp ne i32 %x, %sel
  ret i1 %cmp2
}

; smin(X, Y) < X --> X > Y

define i1 @slt_smin1(i32 %x, i32 %y) {
; CHECK-LABEL: @slt_smin1(
; CHECK-NEXT:    [[CMP2:%.*]] = icmp sgt i32 %x, %y
; CHECK-NEXT:    ret i1 [[CMP2]]
;
  %cmp1 = icmp slt i32 %x, %y
  %sel = select i1 %cmp1, i32 %x, i32 %y
  %cmp2 = icmp slt i32 %sel, %x
  ret i1 %cmp2
}

; Commute min operands.

define i1 @slt_smin2(i32 %x, i32 %y) {
; CHECK-LABEL: @slt_smin2(
; CHECK-NEXT:    [[CMP1:%.*]] = icmp slt i32 %y, %x
; CHECK-NEXT:    ret i1 [[CMP1]]
;
  %cmp1 = icmp slt i32 %y, %x
  %sel = select i1 %cmp1, i32 %y, i32 %x
  %cmp2 = icmp slt i32 %sel, %x
  ret i1 %cmp2
}

; Disguise the icmp predicate by commuting the min op to the RHS.

define i1 @slt_smin3(i32 %a, i32 %y) {
; CHECK-LABEL: @slt_smin3(
; CHECK-NEXT:    [[X:%.*]] = add i32 %a, 3
; CHECK-NEXT:    [[CMP2:%.*]] = icmp sgt i32 [[X]], %y
; CHECK-NEXT:    ret i1 [[CMP2]]
;
  %x = add i32 %a, 3 ; thwart complexity-based canonicalization
  %cmp1 = icmp slt i32 %x, %y
  %sel = select i1 %cmp1, i32 %x, i32 %y
  %cmp2 = icmp sgt i32 %x, %sel
  ret i1 %cmp2
}

; Commute min operands.

define i1 @slt_smin4(i32 %a, i32 %y) {
; CHECK-LABEL: @slt_smin4(
; CHECK-NEXT:    [[X:%.*]] = add i32 %a, 3
; CHECK-NEXT:    [[CMP1:%.*]] = icmp sgt i32 [[X]], %y
; CHECK-NEXT:    ret i1 [[CMP1]]
;
  %x = add i32 %a, 3 ; thwart complexity-based canonicalization
  %cmp1 = icmp slt i32 %y, %x
  %sel = select i1 %cmp1, i32 %y, i32 %x
  %cmp2 = icmp sgt i32 %x, %sel
  ret i1 %cmp2
}

; smin(X, Y) <= X --> true

define i1 @sle_smin1(i32 %x, i32 %y) {
; CHECK-LABEL: @sle_smin1(
; CHECK-NEXT:    ret i1 true
;
  %cmp1 = icmp slt i32 %x, %y
  %sel = select i1 %cmp1, i32 %x, i32 %y
  %cmp2 = icmp sle i32 %sel, %x
  ret i1 %cmp2
}

; Commute min operands.

define i1 @sle_smin2(i32 %x, i32 %y) {
; CHECK-LABEL: @sle_smin2(
; CHECK-NEXT:    ret i1 true
;
  %cmp1 = icmp slt 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 min op to the RHS.

define i1 @sle_smin3(i32 %a, i32 %y) {
; CHECK-LABEL: @sle_smin3(
; CHECK-NEXT:    ret i1 true
;
  %x = add i32 %a, 3 ; thwart complexity-based canonicalization
  %cmp1 = icmp slt i32 %x, %y
  %sel = select i1 %cmp1, i32 %x, i32 %y
  %cmp2 = icmp sge i32 %x, %sel
  ret i1 %cmp2
}

; Commute min operands.

define i1 @sle_smin4(i32 %a, i32 %y) {
; CHECK-LABEL: @sle_smin4(
; CHECK-NEXT:    ret i1 true
;
  %x = add i32 %a, 3 ; thwart complexity-based canonicalization
  %cmp1 = icmp slt i32 %y, %x
  %sel = select i1 %cmp1, i32 %y, i32 %x
  %cmp2 = icmp sge i32 %x, %sel
  ret i1 %cmp2
}

; smin(X, Y) > X --> false

define i1 @sgt_smin1(i32 %x, i32 %y) {
; CHECK-LABEL: @sgt_smin1(
; CHECK-NEXT:    ret i1 false
;
  %cmp1 = icmp slt i32 %x, %y
  %sel = select i1 %cmp1, i32 %x, i32 %y
  %cmp2 = icmp sgt i32 %sel, %x
  ret i1 %cmp2
}

; Commute min operands.

define i1 @sgt_smin2(i32 %x, i32 %y) {
; CHECK-LABEL: @sgt_smin2(
; CHECK-NEXT:    ret i1 false
;
  %cmp1 = icmp slt 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 min op to the RHS.

define i1 @sgt_smin3(i32 %a, i32 %y) {
; CHECK-LABEL: @sgt_smin3(
; CHECK-NEXT:    ret i1 false
;
  %x = add i32 %a, 3 ; thwart complexity-based canonicalization
  %cmp1 = icmp slt i32 %x, %y
  %sel = select i1 %cmp1, i32 %x, i32 %y
  %cmp2 = icmp slt i32 %x, %sel
  ret i1 %cmp2
}

; Commute min operands.

define i1 @sgt_smin4(i32 %a, i32 %y) {
; CHECK-LABEL: @sgt_smin4(
; CHECK-NEXT:    ret i1 false
;
  %x = add i32 %a, 3 ; thwart complexity-based canonicalization
  %cmp1 = icmp slt i32 %y, %x
  %sel = select i1 %cmp1, i32 %y, i32 %x
  %cmp2 = icmp slt i32 %x, %sel
  ret i1 %cmp2
}