test/Transforms/InstCombine/icmp-add.ll

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

; PR1949

define i1 @test1(i32 %a) {
; CHECK-LABEL: @test1(
; CHECK-NEXT:    [[C:%.*]] = icmp ugt i32 [[A:%.*]], -5
; CHECK-NEXT:    ret i1 [[C]]
;
  %b = add i32 %a, 4
  %c = icmp ult i32 %b, 4
  ret i1 %c
}

define <2 x i1> @test1vec(<2 x i32> %a) {
; CHECK-LABEL: @test1vec(
; CHECK-NEXT:    [[C:%.*]] = icmp ugt <2 x i32> [[A:%.*]], <i32 -5, i32 -5>
; CHECK-NEXT:    ret <2 x i1> [[C]]
;
  %b = add <2 x i32> %a, <i32 4, i32 4>
  %c = icmp ult <2 x i32> %b, <i32 4, i32 4>
  ret <2 x i1> %c
}

define i1 @test2(i32 %a) {
; CHECK-LABEL: @test2(
; CHECK-NEXT:    [[C:%.*]] = icmp ult i32 [[A:%.*]], 4
; CHECK-NEXT:    ret i1 [[C]]
;
  %b = sub i32 %a, 4
  %c = icmp ugt i32 %b, -5
  ret i1 %c
}

define <2 x i1> @test2vec(<2 x i32> %a) {
; CHECK-LABEL: @test2vec(
; CHECK-NEXT:    [[C:%.*]] = icmp ult <2 x i32> [[A:%.*]], <i32 4, i32 4>
; CHECK-NEXT:    ret <2 x i1> [[C]]
;
  %b = sub <2 x i32> %a, <i32 4, i32 4>
  %c = icmp ugt <2 x i32> %b, <i32 -5, i32 -5>
  ret <2 x i1> %c
}

define i1 @test3(i32 %a) {
; CHECK-LABEL: @test3(
; CHECK-NEXT:    [[C:%.*]] = icmp sgt i32 [[A:%.*]], 2147483643
; CHECK-NEXT:    ret i1 [[C]]
;
  %b = add i32 %a, 4
  %c = icmp slt i32 %b, 2147483652
  ret i1 %c
}

define <2 x i1> @test3vec(<2 x i32> %a) {
; CHECK-LABEL: @test3vec(
; CHECK-NEXT:    [[C:%.*]] = icmp sgt <2 x i32> [[A:%.*]], <i32 2147483643, i32 2147483643>
; CHECK-NEXT:    ret <2 x i1> [[C]]
;
  %b = add <2 x i32> %a, <i32 4, i32 4>
  %c = icmp slt <2 x i32> %b, <i32 2147483652, i32 2147483652>
  ret <2 x i1> %c
}

define i1 @test4(i32 %a) {
; CHECK-LABEL: @test4(
; CHECK-NEXT:    [[C:%.*]] = icmp slt i32 [[A:%.*]], -4
; CHECK-NEXT:    ret i1 [[C]]
;
  %b = add i32 %a, 2147483652
  %c = icmp sge i32 %b, 4
  ret i1 %c
}

define { i32, i1 } @test4multiuse(i32 %a) {
; CHECK-LABEL: @test4multiuse(
; CHECK-NEXT:    [[B:%.*]] = add i32 [[A:%.*]], -2147483644
; CHECK-NEXT:    [[C:%.*]] = icmp slt i32 [[B]], -4
; CHECK-NEXT:    [[TMP:%.*]] = insertvalue { i32, i1 } undef, i32 [[B]], 0
; CHECK-NEXT:    [[RES:%.*]] = insertvalue { i32, i1 } [[TMP]], i1 [[C]], 1
; CHECK-NEXT:    ret { i32, i1 } [[RES]]
;

  %b = add i32 %a, -2147483644
  %c = icmp slt i32 %b, -4

  %tmp = insertvalue { i32, i1 } undef, i32 %b, 0
  %res = insertvalue { i32, i1 } %tmp, i1 %c, 1

  ret { i32, i1 } %res
}

define <2 x i1> @test4vec(<2 x i32> %a) {
; CHECK-LABEL: @test4vec(
; CHECK-NEXT:    [[C:%.*]] = icmp slt <2 x i32> [[A:%.*]], <i32 -4, i32 -4>
; CHECK-NEXT:    ret <2 x i1> [[C]]
;
  %b = add <2 x i32> %a, <i32 2147483652, i32 2147483652>
  %c = icmp sge <2 x i32> %b, <i32 4, i32 4>
  ret <2 x i1> %c
}

; icmp Pred (add nsw X, C2), C --> icmp Pred X, (C - C2), when C - C2 does not overflow.
; This becomes equality because it's at the limit.

define i1 @nsw_slt1(i8 %a) {
; CHECK-LABEL: @nsw_slt1(
; CHECK-NEXT:    [[C:%.*]] = icmp eq i8 [[A:%.*]], -128
; CHECK-NEXT:    ret i1 [[C]]
;
  %b = add nsw i8 %a, 100
  %c = icmp slt i8 %b, -27
  ret i1 %c
}

define <2 x i1> @nsw_slt1_splat_vec(<2 x i8> %a) {
; CHECK-LABEL: @nsw_slt1_splat_vec(
; CHECK-NEXT:    [[C:%.*]] = icmp eq <2 x i8> [[A:%.*]], <i8 -128, i8 -128>
; CHECK-NEXT:    ret <2 x i1> [[C]]
;
  %b = add nsw <2 x i8> %a, <i8 100, i8 100>
  %c = icmp slt <2 x i8> %b, <i8 -27, i8 -27>
  ret <2 x i1> %c
}

; icmp Pred (add nsw X, C2), C --> icmp Pred X, (C - C2), when C - C2 does not overflow.
; This becomes equality because it's at the limit.

define i1 @nsw_slt2(i8 %a) {
; CHECK-LABEL: @nsw_slt2(
; CHECK-NEXT:    [[C:%.*]] = icmp ne i8 [[A:%.*]], 127
; CHECK-NEXT:    ret i1 [[C]]
;
  %b = add nsw i8 %a, -100
  %c = icmp slt i8 %b, 27
  ret i1 %c
}

define <2 x i1> @nsw_slt2_splat_vec(<2 x i8> %a) {
; CHECK-LABEL: @nsw_slt2_splat_vec(
; CHECK-NEXT:    [[C:%.*]] = icmp ne <2 x i8> [[A:%.*]], <i8 127, i8 127>
; CHECK-NEXT:    ret <2 x i1> [[C]]
;
  %b = add nsw <2 x i8> %a, <i8 -100, i8 -100>
  %c = icmp slt <2 x i8> %b, <i8 27, i8 27>
  ret <2 x i1> %c
}

; icmp Pred (add nsw X, C2), C --> icmp Pred X, (C - C2), when C - C2 does not overflow.
; Less than the limit, so the predicate doesn't change.

define i1 @nsw_slt3(i8 %a) {
; CHECK-LABEL: @nsw_slt3(
; CHECK-NEXT:    [[C:%.*]] = icmp slt i8 [[A:%.*]], -126
; CHECK-NEXT:    ret i1 [[C]]
;
  %b = add nsw i8 %a, 100
  %c = icmp slt i8 %b, -26
  ret i1 %c
}

; icmp Pred (add nsw X, C2), C --> icmp Pred X, (C - C2), when C - C2 does not overflow.
; Less than the limit, so the predicate doesn't change.

define i1 @nsw_slt4(i8 %a) {
; CHECK-LABEL: @nsw_slt4(
; CHECK-NEXT:    [[C:%.*]] = icmp slt i8 [[A:%.*]], 126
; CHECK-NEXT:    ret i1 [[C]]
;
  %b = add nsw i8 %a, -100
  %c = icmp slt i8 %b, 26
  ret i1 %c
}

; icmp Pred (add nsw X, C2), C --> icmp Pred X, (C - C2), when C - C2 does not overflow.
; Try sgt to make sure that works too.

define i1 @nsw_sgt1(i8 %a) {
; CHECK-LABEL: @nsw_sgt1(
; CHECK-NEXT:    [[C:%.*]] = icmp eq i8 [[A:%.*]], 127
; CHECK-NEXT:    ret i1 [[C]]
;
  %b = add nsw i8 %a, -100
  %c = icmp sgt i8 %b, 26
  ret i1 %c
}

define <2 x i1> @nsw_sgt1_splat_vec(<2 x i8> %a) {
; CHECK-LABEL: @nsw_sgt1_splat_vec(
; CHECK-NEXT:    [[C:%.*]] = icmp eq <2 x i8> [[A:%.*]], <i8 127, i8 127>
; CHECK-NEXT:    ret <2 x i1> [[C]]
;
  %b = add nsw <2 x i8> %a, <i8 -100, i8 -100>
  %c = icmp sgt <2 x i8> %b, <i8 26, i8 26>
  ret <2 x i1> %c
}

define i1 @nsw_sgt2(i8 %a) {
; CHECK-LABEL: @nsw_sgt2(
; CHECK-NEXT:    [[C:%.*]] = icmp sgt i8 [[A:%.*]], -126
; CHECK-NEXT:    ret i1 [[C]]
;
  %b = add nsw i8 %a, 100
  %c = icmp sgt i8 %b, -26
  ret i1 %c
}

define <2 x i1> @nsw_sgt2_splat_vec(<2 x i8> %a) {
; CHECK-LABEL: @nsw_sgt2_splat_vec(
; CHECK-NEXT:    [[C:%.*]] = icmp sgt <2 x i8> [[A:%.*]], <i8 -126, i8 -126>
; CHECK-NEXT:    ret <2 x i1> [[C]]
;
  %b = add nsw <2 x i8> %a, <i8 100, i8 100>
  %c = icmp sgt <2 x i8> %b, <i8 -26, i8 -26>
  ret <2 x i1> %c
}

; icmp Pred (add nsw X, C2), C --> icmp Pred X, (C - C2), when C - C2 does not overflow.
; Comparison with 0 doesn't need special-casing.

define i1 @slt_zero_add_nsw(i32 %a) {
; CHECK-LABEL: @slt_zero_add_nsw(
; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[A:%.*]], -1
; CHECK-NEXT:    ret i1 [[CMP]]
;
  %add = add nsw i32 %a, 1
  %cmp = icmp slt i32 %add, 0
  ret i1 %cmp
}

; The same fold should work with vectors.

define <2 x i1> @slt_zero_add_nsw_splat_vec(<2 x i8> %a) {
; CHECK-LABEL: @slt_zero_add_nsw_splat_vec(
; CHECK-NEXT:    [[CMP:%.*]] = icmp slt <2 x i8> [[A:%.*]], <i8 -1, i8 -1>
; CHECK-NEXT:    ret <2 x i1> [[CMP]]
;
  %add = add nsw <2 x i8> %a, <i8 1, i8 1>
  %cmp = icmp slt <2 x i8> %add, zeroinitializer
  ret <2 x i1> %cmp
}

; Test the edges - instcombine should not interfere with simplification to constants.
; Constant subtraction does not overflow, but this is false.

define i1 @nsw_slt3_ov_no(i8 %a) {
; CHECK-LABEL: @nsw_slt3_ov_no(
; CHECK-NEXT:    ret i1 false
;
  %b = add nsw i8 %a, 100
  %c = icmp slt i8 %b, -28
  ret i1 %c
}

; Test the edges - instcombine should not interfere with simplification to constants.
; Constant subtraction overflows. This is false.

define i1 @nsw_slt4_ov(i8 %a) {
; CHECK-LABEL: @nsw_slt4_ov(
; CHECK-NEXT:    ret i1 false
;
  %b = add nsw i8 %a, 100
  %c = icmp slt i8 %b, -29
  ret i1 %c
}

; Test the edges - instcombine should not interfere with simplification to constants.
; Constant subtraction overflows. This is true.

define i1 @nsw_slt5_ov(i8 %a) {
; CHECK-LABEL: @nsw_slt5_ov(
; CHECK-NEXT:    ret i1 true
;
  %b = add nsw i8 %a, -100
  %c = icmp slt i8 %b, 28
  ret i1 %c
}

; InstCombine should not thwart this opportunity to simplify completely.

define i1 @slt_zero_add_nsw_signbit(i8 %x) {
; CHECK-LABEL: @slt_zero_add_nsw_signbit(
; CHECK-NEXT:    ret i1 true
;
  %y = add nsw i8 %x, -128
  %z = icmp slt i8 %y, 0
  ret i1 %z
}

; InstCombine should not thwart this opportunity to simplify completely.

define i1 @slt_zero_add_nuw_signbit(i8 %x) {
; CHECK-LABEL: @slt_zero_add_nuw_signbit(
; CHECK-NEXT:    ret i1 true
;
  %y = add nuw i8 %x, 128
  %z = icmp slt i8 %y, 0
  ret i1 %z
}

define i1 @reduce_add_ult(i32 %in) {
; CHECK-LABEL: @reduce_add_ult(
; CHECK-NEXT:    [[A18:%.*]] = icmp ult i32 [[IN:%.*]], 9
; CHECK-NEXT:    ret i1 [[A18]]
;
  %a6 = add nuw i32 %in, 3
  %a18 = icmp ult i32 %a6, 12
  ret i1 %a18
}

define i1 @reduce_add_ugt(i32 %in) {
; CHECK-LABEL: @reduce_add_ugt(
; CHECK-NEXT:    [[A18:%.*]] = icmp ugt i32 [[IN:%.*]], 9
; CHECK-NEXT:    ret i1 [[A18]]
;
  %a6 = add nuw i32 %in, 3
  %a18 = icmp ugt i32 %a6, 12
  ret i1 %a18
}

define i1 @reduce_add_ule(i32 %in) {
; CHECK-LABEL: @reduce_add_ule(
; CHECK-NEXT:    [[A18:%.*]] = icmp ult i32 [[IN:%.*]], 10
; CHECK-NEXT:    ret i1 [[A18]]
;
  %a6 = add nuw i32 %in, 3
  %a18 = icmp ule i32 %a6, 12
  ret i1 %a18
}

define i1 @reduce_add_uge(i32 %in) {
; CHECK-LABEL: @reduce_add_uge(
; CHECK-NEXT:    [[A18:%.*]] = icmp ugt i32 [[IN:%.*]], 8
; CHECK-NEXT:    ret i1 [[A18]]
;
  %a6 = add nuw i32 %in, 3
  %a18 = icmp uge i32 %a6, 12
  ret i1 %a18
}

define i1 @ult_add_ssubov(i32 %in) {
; CHECK-LABEL: @ult_add_ssubov(
; CHECK-NEXT:    ret i1 false
;
  %a6 = add nuw i32 %in, 71
  %a18 = icmp ult i32 %a6, 3
  ret i1 %a18
}

define i1 @ult_add_nonuw(i8 %in) {
; CHECK-LABEL: @ult_add_nonuw(
; CHECK-NEXT:    [[A6:%.*]] = add i8 [[IN:%.*]], 71
; CHECK-NEXT:    [[A18:%.*]] = icmp ult i8 [[A6]], 12
; CHECK-NEXT:    ret i1 [[A18]]
;
  %a6 = add i8 %in, 71
  %a18 = icmp ult i8 %a6, 12
  ret i1 %a18
}

define i1 @uge_add_nonuw(i32 %in) {
; CHECK-LABEL: @uge_add_nonuw(
; CHECK-NEXT:    [[A6:%.*]] = add i32 [[IN:%.*]], 3
; CHECK-NEXT:    [[A18:%.*]] = icmp ugt i32 [[A6]], 11
; CHECK-NEXT:    ret i1 [[A18]]
;
  %a6 = add i32 %in, 3
  %a18 = icmp uge i32 %a6, 12
  ret i1 %a18
}

; Test unsigned add overflow patterns. The div ops are only here to
; thwart complexity based canonicalization of the operand order.

define i1 @op_ugt_sum_commute1(i8 %p1, i8 %p2) {
; CHECK-LABEL: @op_ugt_sum_commute1(
; CHECK-NEXT:    [[X:%.*]] = sdiv i8 42, [[P1:%.*]]
; CHECK-NEXT:    [[Y:%.*]] = sdiv i8 42, [[P2:%.*]]
; CHECK-NEXT:    [[TMP1:%.*]] = xor i8 [[X]], -1
; CHECK-NEXT:    [[C:%.*]] = icmp ugt i8 [[Y]], [[TMP1]]
; CHECK-NEXT:    ret i1 [[C]]
;
  %x = sdiv i8 42, %p1
  %y = sdiv i8 42, %p2
  %a = add i8 %x, %y
  %c = icmp ugt i8 %x, %a
  ret i1 %c
}

define <2 x i1> @op_ugt_sum_vec_commute2(<2 x i8> %p1, <2 x i8> %p2) {
; CHECK-LABEL: @op_ugt_sum_vec_commute2(
; CHECK-NEXT:    [[X:%.*]] = sdiv <2 x i8> <i8 42, i8 -42>, [[P1:%.*]]
; CHECK-NEXT:    [[Y:%.*]] = sdiv <2 x i8> <i8 42, i8 -42>, [[P2:%.*]]
; CHECK-NEXT:    [[TMP1:%.*]] = xor <2 x i8> [[X]], <i8 -1, i8 -1>
; CHECK-NEXT:    [[C:%.*]] = icmp ugt <2 x i8> [[Y]], [[TMP1]]
; CHECK-NEXT:    ret <2 x i1> [[C]]
;
  %x = sdiv <2 x i8> <i8 42, i8 -42>, %p1
  %y = sdiv <2 x i8> <i8 42, i8 -42>, %p2
  %a = add <2 x i8> %y, %x
  %c = icmp ugt <2 x i8> %x, %a
  ret <2 x i1> %c
}

define i1 @sum_ugt_op_uses(i8 %p1, i8 %p2, i8* %p3) {
; CHECK-LABEL: @sum_ugt_op_uses(
; CHECK-NEXT:    [[X:%.*]] = sdiv i8 42, [[P1:%.*]]
; CHECK-NEXT:    [[Y:%.*]] = sdiv i8 42, [[P2:%.*]]
; CHECK-NEXT:    [[A:%.*]] = add i8 [[X]], [[Y]]
; CHECK-NEXT:    store i8 [[A]], i8* [[P3:%.*]], align 1
; CHECK-NEXT:    [[C:%.*]] = icmp ugt i8 [[X]], [[A]]
; CHECK-NEXT:    ret i1 [[C]]
;
  %x = sdiv i8 42, %p1
  %y = sdiv i8 42, %p2
  %a = add i8 %x, %y
  store i8 %a, i8* %p3
  %c = icmp ugt i8 %x, %a
  ret i1 %c
}

define <2 x i1> @sum_ult_op_vec_commute1(<2 x i8> %p1, <2 x i8> %p2) {
; CHECK-LABEL: @sum_ult_op_vec_commute1(
; CHECK-NEXT:    [[X:%.*]] = sdiv <2 x i8> <i8 42, i8 -42>, [[P1:%.*]]
; CHECK-NEXT:    [[Y:%.*]] = sdiv <2 x i8> <i8 -42, i8 42>, [[P2:%.*]]
; CHECK-NEXT:    [[TMP1:%.*]] = xor <2 x i8> [[X]], <i8 -1, i8 -1>
; CHECK-NEXT:    [[C:%.*]] = icmp ugt <2 x i8> [[Y]], [[TMP1]]
; CHECK-NEXT:    ret <2 x i1> [[C]]
;
  %x = sdiv <2 x i8> <i8 42, i8 -42>, %p1
  %y = sdiv <2 x i8> <i8 -42, i8 42>, %p2
  %a = add <2 x i8> %x, %y
  %c = icmp ult <2 x i8> %a, %x
  ret <2 x i1> %c
}

define i1 @sum_ult_op_commute2(i8 %p1, i8 %p2) {
; CHECK-LABEL: @sum_ult_op_commute2(
; CHECK-NEXT:    [[X:%.*]] = sdiv i8 42, [[P1:%.*]]
; CHECK-NEXT:    [[Y:%.*]] = sdiv i8 42, [[P2:%.*]]
; CHECK-NEXT:    [[TMP1:%.*]] = xor i8 [[X]], -1
; CHECK-NEXT:    [[C:%.*]] = icmp ugt i8 [[Y]], [[TMP1]]
; CHECK-NEXT:    ret i1 [[C]]
;
  %x = sdiv i8 42, %p1
  %y = sdiv i8 42, %p2
  %a = add i8 %y, %x
  %c = icmp ult i8 %a, %x
  ret i1 %c
}

define i1 @sum_ult_op_uses(i8 %x, i8 %y, i8* %p) {
; CHECK-LABEL: @sum_ult_op_uses(
; CHECK-NEXT:    [[A:%.*]] = add i8 [[Y:%.*]], [[X:%.*]]
; CHECK-NEXT:    store i8 [[A]], i8* [[P:%.*]], align 1
; CHECK-NEXT:    [[C:%.*]] = icmp ult i8 [[A]], [[X]]
; CHECK-NEXT:    ret i1 [[C]]
;
  %a = add i8 %y, %x
  store i8 %a, i8* %p
  %c = icmp ult i8 %a, %x
  ret i1 %c
}