test/Transforms/InstSimplify/select.ll

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

define i1 @bool_true_or_false(i1 %cond) {
; CHECK-LABEL: @bool_true_or_false(
; CHECK-NEXT:    ret i1 [[COND:%.*]]
;
  %s = select i1 %cond, i1 true, i1 false
  ret i1 %s
}

define i1 @cond_constexpr_bool_true_or_false(i1 %cond) {
; CHECK-LABEL: @cond_constexpr_bool_true_or_false(
; CHECK-NEXT:    ret i1 ptrtoint (ptr @cond_constexpr_bool_true_or_false to i1)
;
  %s = select i1 ptrtoint (ptr @cond_constexpr_bool_true_or_false to i1), i1 true, i1 false
  ret i1 %s
}

define <2 x i1> @bool_true_or_false_vec(<2 x i1> %cond) {
; CHECK-LABEL: @bool_true_or_false_vec(
; CHECK-NEXT:    ret <2 x i1> [[COND:%.*]]
;
  %s = select <2 x i1> %cond, <2 x i1> <i1 true, i1 true>, <2 x i1> zeroinitializer
  ret <2 x i1> %s
}

define <2 x i1> @bool_true_or_false_vec_undef(<2 x i1> %cond) {
; CHECK-LABEL: @bool_true_or_false_vec_undef(
; CHECK-NEXT:    ret <2 x i1> [[COND:%.*]]
;
  %s = select <2 x i1> %cond, <2 x i1> <i1 undef, i1 true>, <2 x i1> <i1 false, i1 undef>
  ret <2 x i1> %s
}

define i32 @cond_is_false(i32 %A, i32 %B) {
; CHECK-LABEL: @cond_is_false(
; CHECK-NEXT:    ret i32 [[B:%.*]]
;
  %C = select i1 false, i32 %A, i32 %B
  ret i32 %C
}

define i32 @cond_is_true(i32 %A, i32 %B) {
; CHECK-LABEL: @cond_is_true(
; CHECK-NEXT:    ret i32 [[A:%.*]]
;
  %C = select i1 true, i32 %A, i32 %B
  ret i32 %C
}

define i32 @equal_arms(i1 %cond, i32 %x) {
; CHECK-LABEL: @equal_arms(
; CHECK-NEXT:    ret i32 [[X:%.*]]
;
  %V = select i1 %cond, i32 %x, i32 %x
  ret i32 %V
}

define <2 x i32> @equal_arms_vec(<2 x i1> %cond, <2 x i32> %x) {
; CHECK-LABEL: @equal_arms_vec(
; CHECK-NEXT:    ret <2 x i32> [[X:%.*]]
;
  %V = select <2 x i1> %cond, <2 x i32> %x, <2 x i32> %x
  ret <2 x i32> %V
}

define <2 x i32> @equal_arms_vec_undef(<2 x i1> %cond) {
; CHECK-LABEL: @equal_arms_vec_undef(
; CHECK-NEXT:    ret <2 x i32> <i32 42, i32 42>
;
  %V = select <2 x i1> %cond, <2 x i32> <i32 42, i32 undef>, <2 x i32> <i32 undef, i32 42>
  ret <2 x i32> %V
}

define <3 x float> @equal_arms_vec_less_undef(<3 x i1> %cond) {
; CHECK-LABEL: @equal_arms_vec_less_undef(
; CHECK-NEXT:    ret <3 x float> <float 4.200000e+01, float 4.200000e+01, float 4.300000e+01>
;
  %V = select <3 x i1> %cond, <3 x float> <float 42.0, float undef, float 43.0>, <3 x float> <float 42.0, float 42.0, float 43.0>
  ret <3 x float> %V
}

define <3 x float> @equal_arms_vec_more_undef(<3 x i1> %cond) {
; CHECK-LABEL: @equal_arms_vec_more_undef(
; CHECK-NEXT:    ret <3 x float> <float 4.200000e+01, float undef, float 4.300000e+01>
;
  %V = select <3 x i1> %cond, <3 x float> <float 42.0, float undef, float undef>, <3 x float> <float undef, float undef, float 43.0>
  ret <3 x float> %V
}

define <2 x i8> @vsel_tvec(<2 x i8> %x, <2 x i8> %y) {
; CHECK-LABEL: @vsel_tvec(
; CHECK-NEXT:    ret <2 x i8> [[X:%.*]]
;
  %s = select <2 x i1><i1 true, i1 true>, <2 x i8> %x, <2 x i8> %y
  ret <2 x i8> %s
}

define <2 x i8> @vsel_fvec(<2 x i8> %x, <2 x i8> %y) {
; CHECK-LABEL: @vsel_fvec(
; CHECK-NEXT:    ret <2 x i8> [[Y:%.*]]
;
  %s = select <2 x i1><i1 false, i1 false>, <2 x i8> %x, <2 x i8> %y
  ret <2 x i8> %s
}

define <2 x i8> @vsel_mixedvec() {
; CHECK-LABEL: @vsel_mixedvec(
; CHECK-NEXT:    ret <2 x i8> <i8 0, i8 3>
;
  %s = select <2 x i1><i1 true, i1 false>, <2 x i8> <i8 0, i8 1>, <2 x i8> <i8 2, i8 3>
  ret <2 x i8> %s
}

define <3 x i8> @vsel_undef_true_op(<3 x i8> %x, <3 x i8> %y) {
; CHECK-LABEL: @vsel_undef_true_op(
; CHECK-NEXT:    ret <3 x i8> [[X:%.*]]
;
  %s = select <3 x i1><i1 1, i1 undef, i1 1>, <3 x i8> %x, <3 x i8> %y
  ret <3 x i8> %s
}

define <3 x i4> @vsel_undef_false_op(<3 x i4> %x, <3 x i4> %y) {
; CHECK-LABEL: @vsel_undef_false_op(
; CHECK-NEXT:    ret <3 x i4> [[Y:%.*]]
;
  %s = select <3 x i1><i1 0, i1 undef, i1 undef>, <3 x i4> %x, <3 x i4> %y
  ret <3 x i4> %s
}

define i32 @test1(i32 %x) {
; CHECK-LABEL: @test1(
; CHECK-NEXT:    ret i32 [[X:%.*]]
;
  %and = and i32 %x, 1
  %cmp = icmp eq i32 %and, 0
  %and1 = and i32 %x, -2
  %and1.x = select i1 %cmp, i32 %and1, i32 %x
  ret i32 %and1.x
}

define i32 @test2(i32 %x) {
; CHECK-LABEL: @test2(
; CHECK-NEXT:    ret i32 [[X:%.*]]
;
  %and = and i32 %x, 1
  %cmp = icmp ne i32 %and, 0
  %and1 = and i32 %x, -2
  %and1.x = select i1 %cmp, i32 %x, i32 %and1
  ret i32 %and1.x
}

define i32 @test3(i32 %x) {
; CHECK-LABEL: @test3(
; CHECK-NEXT:    [[AND1:%.*]] = and i32 [[X:%.*]], -2
; CHECK-NEXT:    ret i32 [[AND1]]
;
  %and = and i32 %x, 1
  %cmp = icmp ne i32 %and, 0
  %and1 = and i32 %x, -2
  %and1.x = select i1 %cmp, i32 %and1, i32 %x
  ret i32 %and1.x
}

define i32 @test4(i32 %X) {
; CHECK-LABEL: @test4(
; CHECK-NEXT:    [[OR:%.*]] = or i32 [[X:%.*]], -2147483648
; CHECK-NEXT:    ret i32 [[OR]]
;
  %cmp = icmp slt i32 %X, 0
  %or = or i32 %X, -2147483648
  %cond = select i1 %cmp, i32 %X, i32 %or
  ret i32 %cond
}

; Same as above, but the compare isn't canonical
define i32 @test4noncanon(i32 %X) {
; CHECK-LABEL: @test4noncanon(
; CHECK-NEXT:    [[OR:%.*]] = or i32 [[X:%.*]], -2147483648
; CHECK-NEXT:    ret i32 [[OR]]
;
  %cmp = icmp sle i32 %X, -1
  %or = or i32 %X, -2147483648
  %cond = select i1 %cmp, i32 %X, i32 %or
  ret i32 %cond
}

define i32 @test5(i32 %X) {
; CHECK-LABEL: @test5(
; CHECK-NEXT:    ret i32 [[X:%.*]]
;
  %cmp = icmp slt i32 %X, 0
  %or = or i32 %X, -2147483648
  %cond = select i1 %cmp, i32 %or, i32 %X
  ret i32 %cond
}

define i32 @test6(i32 %X) {
; CHECK-LABEL: @test6(
; CHECK-NEXT:    [[AND:%.*]] = and i32 [[X:%.*]], 2147483647
; CHECK-NEXT:    ret i32 [[AND]]
;
  %cmp = icmp slt i32 %X, 0
  %and = and i32 %X, 2147483647
  %cond = select i1 %cmp, i32 %and, i32 %X
  ret i32 %cond
}

define i32 @test7(i32 %X) {
; CHECK-LABEL: @test7(
; CHECK-NEXT:    ret i32 [[X:%.*]]
;
  %cmp = icmp slt i32 %X, 0
  %and = and i32 %X, 2147483647
  %cond = select i1 %cmp, i32 %X, i32 %and
  ret i32 %cond
}

define i32 @test8(i32 %X) {
; CHECK-LABEL: @test8(
; CHECK-NEXT:    ret i32 [[X:%.*]]
;
  %cmp = icmp sgt i32 %X, -1
  %or = or i32 %X, -2147483648
  %cond = select i1 %cmp, i32 %X, i32 %or
  ret i32 %cond
}

define i32 @test9(i32 %X) {
; CHECK-LABEL: @test9(
; CHECK-NEXT:    [[OR:%.*]] = or i32 [[X:%.*]], -2147483648
; CHECK-NEXT:    ret i32 [[OR]]
;
  %cmp = icmp sgt i32 %X, -1
  %or = or i32 %X, -2147483648
  %cond = select i1 %cmp, i32 %or, i32 %X
  ret i32 %cond
}

; Same as above, but the compare isn't canonical
define i32 @test9noncanon(i32 %X) {
; CHECK-LABEL: @test9noncanon(
; CHECK-NEXT:    [[OR:%.*]] = or i32 [[X:%.*]], -2147483648
; CHECK-NEXT:    ret i32 [[OR]]
;
  %cmp = icmp sge i32 %X, 0
  %or = or i32 %X, -2147483648
  %cond = select i1 %cmp, i32 %or, i32 %X
  ret i32 %cond
}

define i32 @test10(i32 %X) {
; CHECK-LABEL: @test10(
; CHECK-NEXT:    ret i32 [[X:%.*]]
;
  %cmp = icmp sgt i32 %X, -1
  %and = and i32 %X, 2147483647
  %cond = select i1 %cmp, i32 %and, i32 %X
  ret i32 %cond
}

define i32 @test11(i32 %X) {
; CHECK-LABEL: @test11(
; CHECK-NEXT:    [[AND:%.*]] = and i32 [[X:%.*]], 2147483647
; CHECK-NEXT:    ret i32 [[AND]]
;
  %cmp = icmp sgt i32 %X, -1
  %and = and i32 %X, 2147483647
  %cond = select i1 %cmp, i32 %X, i32 %and
  ret i32 %cond
}

define <2 x i8> @test11vec(<2 x i8> %X) {
; CHECK-LABEL: @test11vec(
; CHECK-NEXT:    [[AND:%.*]] = and <2 x i8> [[X:%.*]], <i8 127, i8 127>
; CHECK-NEXT:    ret <2 x i8> [[AND]]
;
  %cmp = icmp sgt <2 x i8> %X, <i8 -1, i8 -1>
  %and = and <2 x i8> %X, <i8 127, i8 127>
  %sel = select <2 x i1> %cmp, <2 x i8> %X, <2 x i8> %and
  ret <2 x i8> %sel
}

define i32 @test12(i32 %X) {
; CHECK-LABEL: @test12(
; CHECK-NEXT:    [[AND:%.*]] = and i32 [[X:%.*]], 3
; CHECK-NEXT:    ret i32 [[AND]]
;
  %cmp = icmp ult i32 %X, 4
  %and = and i32 %X, 3
  %cond = select i1 %cmp, i32 %X, i32 %and
  ret i32 %cond
}

; Same as above, but the compare isn't canonical
define i32 @test12noncanon(i32 %X) {
; CHECK-LABEL: @test12noncanon(
; CHECK-NEXT:    [[AND:%.*]] = and i32 [[X:%.*]], 3
; CHECK-NEXT:    ret i32 [[AND]]
;
  %cmp = icmp ule i32 %X, 3
  %and = and i32 %X, 3
  %cond = select i1 %cmp, i32 %X, i32 %and
  ret i32 %cond
}

define i32 @test13(i32 %X) {
; CHECK-LABEL: @test13(
; CHECK-NEXT:    [[AND:%.*]] = and i32 [[X:%.*]], 3
; CHECK-NEXT:    ret i32 [[AND]]
;
  %cmp = icmp ugt i32 %X, 3
  %and = and i32 %X, 3
  %cond = select i1 %cmp, i32 %and, i32 %X
  ret i32 %cond
}

; Same as above, but the compare isn't canonical
define i32 @test13noncanon(i32 %X) {
; CHECK-LABEL: @test13noncanon(
; CHECK-NEXT:    [[AND:%.*]] = and i32 [[X:%.*]], 3
; CHECK-NEXT:    ret i32 [[AND]]
;
  %cmp = icmp uge i32 %X, 4
  %and = and i32 %X, 3
  %cond = select i1 %cmp, i32 %and, i32 %X
  ret i32 %cond
}

define i32 @select_icmp_and_8_eq_0_or_8(i32 %x) {
; CHECK-LABEL: @select_icmp_and_8_eq_0_or_8(
; CHECK-NEXT:    [[OR:%.*]] = or i32 [[X:%.*]], 8
; CHECK-NEXT:    ret i32 [[OR]]
;
  %and = and i32 %x, 8
  %cmp = icmp eq i32 %and, 0
  %or = or i32 %x, 8
  %sel = select i1 %cmp, i32 %or, i32 %x
  ret i32 %sel
}

define i32 @select_icmp_and_8_eq_0_or_8_alt(i32 %x) {
; CHECK-LABEL: @select_icmp_and_8_eq_0_or_8_alt(
; CHECK-NEXT:    [[OR:%.*]] = or i32 [[X:%.*]], 8
; CHECK-NEXT:    ret i32 [[OR]]
;
  %and = and i32 %x, 8
  %cmp = icmp ne i32 %and, 0
  %or = or i32 %x, 8
  %sel = select i1 %cmp, i32 %x, i32 %or
  ret i32 %sel
}

define i32 @select_icmp_and_8_ne_0_or_8(i32 %x) {
; CHECK-LABEL: @select_icmp_and_8_ne_0_or_8(
; CHECK-NEXT:    ret i32 [[X:%.*]]
;
  %and = and i32 %x, 8
  %cmp = icmp ne i32 %and, 0
  %or = or i32 %x, 8
  %sel = select i1 %cmp, i32 %or, i32 %x
  ret i32 %sel
}

define i32 @select_icmp_and_8_ne_0_or_8_alt(i32 %x) {
; CHECK-LABEL: @select_icmp_and_8_ne_0_or_8_alt(
; CHECK-NEXT:    ret i32 [[X:%.*]]
;
  %and = and i32 %x, 8
  %cmp = icmp eq i32 %and, 0
  %or = or i32 %x, 8
  %sel = select i1 %cmp, i32 %x, i32 %or
  ret i32 %sel
}

define i32 @select_icmp_and_8_eq_0_and_not_8(i32 %x) {
; CHECK-LABEL: @select_icmp_and_8_eq_0_and_not_8(
; CHECK-NEXT:    [[AND1:%.*]] = and i32 [[X:%.*]], -9
; CHECK-NEXT:    ret i32 [[AND1]]
;
  %and = and i32 %x, 8
  %cmp = icmp eq i32 %and, 0
  %and1 = and i32 %x, -9
  %sel = select i1 %cmp, i32 %x, i32 %and1
  ret i32 %sel
}

define i32 @select_icmp_and_8_eq_0_and_not_8_alt(i32 %x) {
; CHECK-LABEL: @select_icmp_and_8_eq_0_and_not_8_alt(
; CHECK-NEXT:    [[AND1:%.*]] = and i32 [[X:%.*]], -9
; CHECK-NEXT:    ret i32 [[AND1]]
;
  %and = and i32 %x, 8
  %cmp = icmp ne i32 %and, 0
  %and1 = and i32 %x, -9
  %sel = select i1 %cmp, i32 %and1, i32 %x
  ret i32 %sel
}

define i32 @select_icmp_and_8_ne_0_and_not_8(i32 %x) {
; CHECK-LABEL: @select_icmp_and_8_ne_0_and_not_8(
; CHECK-NEXT:    ret i32 [[X:%.*]]
;
  %and = and i32 %x, 8
  %cmp = icmp ne i32 %and, 0
  %and1 = and i32 %x, -9
  %sel = select i1 %cmp, i32 %x, i32 %and1
  ret i32 %sel
}

define i32 @select_icmp_and_8_ne_0_and_not_8_alt(i32 %x) {
; CHECK-LABEL: @select_icmp_and_8_ne_0_and_not_8_alt(
; CHECK-NEXT:    ret i32 [[X:%.*]]
;
  %and = and i32 %x, 8
  %cmp = icmp eq i32 %and, 0
  %and1 = and i32 %x, -9
  %sel = select i1 %cmp, i32 %and1, i32 %x
  ret i32 %sel
}

; PR28466: https://llvm.org/bugs/show_bug.cgi?id=28466
; Each of the previous 8 patterns has a variant that replaces the
; 'and' with a 'trunc' and the icmp eq/ne with icmp slt/sgt.

define i32 @select_icmp_trunc_8_ne_0_or_128(i32 %x) {
; CHECK-LABEL: @select_icmp_trunc_8_ne_0_or_128(
; CHECK-NEXT:    [[OR:%.*]] = or i32 [[X:%.*]], 128
; CHECK-NEXT:    ret i32 [[OR]]
;
  %trunc = trunc i32 %x to i8
  %cmp = icmp sgt i8 %trunc, -1
  %or = or i32 %x, 128
  %sel = select i1 %cmp, i32 %or, i32 %x
  ret i32 %sel
}

define i32 @select_icmp_trunc_8_ne_0_or_128_alt(i32 %x) {
; CHECK-LABEL: @select_icmp_trunc_8_ne_0_or_128_alt(
; CHECK-NEXT:    [[OR:%.*]] = or i32 [[X:%.*]], 128
; CHECK-NEXT:    ret i32 [[OR]]
;
  %trunc = trunc i32 %x to i8
  %cmp = icmp slt i8 %trunc, 0
  %or = or i32 %x, 128
  %sel = select i1 %cmp, i32 %x, i32 %or
  ret i32 %sel
}

define i32 @select_icmp_trunc_8_eq_0_or_128(i32 %x) {
; CHECK-LABEL: @select_icmp_trunc_8_eq_0_or_128(
; CHECK-NEXT:    ret i32 [[X:%.*]]
;
  %trunc = trunc i32 %x to i8
  %cmp = icmp slt i8 %trunc, 0
  %or = or i32 %x, 128
  %sel = select i1 %cmp, i32 %or, i32 %x
  ret i32 %sel
}

define i32 @select_icmp_trunc_8_eq_0_or_128_alt(i32 %x) {
; CHECK-LABEL: @select_icmp_trunc_8_eq_0_or_128_alt(
; CHECK-NEXT:    ret i32 [[X:%.*]]
;
  %trunc = trunc i32 %x to i8
  %cmp = icmp sgt i8 %trunc, -1
  %or = or i32 %x, 128
  %sel = select i1 %cmp, i32 %x, i32 %or
  ret i32 %sel
}

define i32 @select_icmp_trunc_8_eq_0_and_not_8(i32 %x) {
; CHECK-LABEL: @select_icmp_trunc_8_eq_0_and_not_8(
; CHECK-NEXT:    [[AND:%.*]] = and i32 [[X:%.*]], -9
; CHECK-NEXT:    ret i32 [[AND]]
;
  %trunc = trunc i32 %x to i4
  %cmp = icmp sgt i4 %trunc, -1
  %and = and i32 %x, -9
  %sel = select i1 %cmp, i32 %x, i32 %and
  ret i32 %sel
}

define i32 @select_icmp_trunc_8_eq_0_and_not_8_alt(i32 %x) {
; CHECK-LABEL: @select_icmp_trunc_8_eq_0_and_not_8_alt(
; CHECK-NEXT:    [[AND:%.*]] = and i32 [[X:%.*]], -9
; CHECK-NEXT:    ret i32 [[AND]]
;
  %trunc = trunc i32 %x to i4
  %cmp = icmp slt i4 %trunc, 0
  %and = and i32 %x, -9
  %sel = select i1 %cmp, i32 %and, i32 %x
  ret i32 %sel
}

define i32 @select_icmp_trunc_8_ne_0_and_not_8(i32 %x) {
; CHECK-LABEL: @select_icmp_trunc_8_ne_0_and_not_8(
; CHECK-NEXT:    ret i32 [[X:%.*]]
;
  %trunc = trunc i32 %x to i4
  %cmp = icmp slt i4 %trunc, 0
  %and = and i32 %x, -9
  %sel = select i1 %cmp, i32 %x, i32 %and
  ret i32 %sel
}

define i32 @select_icmp_trunc_8_ne_0_and_not_8_alt(i32 %x) {
; CHECK-LABEL: @select_icmp_trunc_8_ne_0_and_not_8_alt(
; CHECK-NEXT:    ret i32 [[X:%.*]]
;
  %trunc = trunc i32 %x to i4
  %cmp = icmp sgt i4 %trunc, -1
  %and = and i32 %x, -9
  %sel = select i1 %cmp, i32 %and, i32 %x
  ret i32 %sel
}

; Make sure that at least a few of the same patterns are repeated with vector types.

define <2 x i32> @select_icmp_and_8_ne_0_and_not_8_vec(<2 x i32> %x) {
; CHECK-LABEL: @select_icmp_and_8_ne_0_and_not_8_vec(
; CHECK-NEXT:    ret <2 x i32> [[X:%.*]]
;
  %and = and <2 x i32> %x, <i32 8, i32 8>
  %cmp = icmp ne <2 x i32> %and, zeroinitializer
  %and1 = and <2 x i32> %x, <i32 -9, i32 -9>
  %sel = select <2 x i1> %cmp, <2 x i32> %x, <2 x i32> %and1
  ret <2 x i32> %sel
}

define <2 x i32> @select_icmp_trunc_8_ne_0_and_not_8_alt_vec(<2 x i32> %x) {
; CHECK-LABEL: @select_icmp_trunc_8_ne_0_and_not_8_alt_vec(
; CHECK-NEXT:    ret <2 x i32> [[X:%.*]]
;
  %trunc = trunc <2 x i32> %x to <2 x i4>
  %cmp = icmp sgt <2 x i4> %trunc, <i4 -1, i4 -1>
  %and = and <2 x i32> %x, <i32 -9, i32 -9>
  %sel = select <2 x i1> %cmp, <2 x i32> %and, <2 x i32> %x
  ret <2 x i32> %sel
}

; Insert a bit from x into y? This should be possible in InstCombine, but not InstSimplify?

define i32 @select_icmp_x_and_8_eq_0_y_and_not_8(i32 %x, i32 %y) {
; CHECK-LABEL: @select_icmp_x_and_8_eq_0_y_and_not_8(
; CHECK-NEXT:    [[AND:%.*]] = and i32 [[X:%.*]], 8
; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i32 [[AND]], 0
; CHECK-NEXT:    [[AND1:%.*]] = and i32 [[Y:%.*]], -9
; CHECK-NEXT:    [[Y_AND1:%.*]] = select i1 [[CMP]], i32 [[Y]], i32 [[AND1]]
; CHECK-NEXT:    ret i32 [[Y_AND1]]
;
  %and = and i32 %x, 8
  %cmp = icmp eq i32 %and, 0
  %and1 = and i32 %y, -9
  %y.and1 = select i1 %cmp, i32 %y, i32 %and1
  ret i32 %y.and1
}

define i64 @select_icmp_x_and_8_eq_0_y64_and_not_8(i32 %x, i64 %y) {
; CHECK-LABEL: @select_icmp_x_and_8_eq_0_y64_and_not_8(
; CHECK-NEXT:    [[AND:%.*]] = and i32 [[X:%.*]], 8
; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i32 [[AND]], 0
; CHECK-NEXT:    [[AND1:%.*]] = and i64 [[Y:%.*]], -9
; CHECK-NEXT:    [[Y_AND1:%.*]] = select i1 [[CMP]], i64 [[Y]], i64 [[AND1]]
; CHECK-NEXT:    ret i64 [[Y_AND1]]
;
  %and = and i32 %x, 8
  %cmp = icmp eq i32 %and, 0
  %and1 = and i64 %y, -9
  %y.and1 = select i1 %cmp, i64 %y, i64 %and1
  ret i64 %y.and1
}

define i64 @select_icmp_x_and_8_ne_0_y64_and_not_8(i32 %x, i64 %y) {
; CHECK-LABEL: @select_icmp_x_and_8_ne_0_y64_and_not_8(
; CHECK-NEXT:    [[AND:%.*]] = and i32 [[X:%.*]], 8
; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i32 [[AND]], 0
; CHECK-NEXT:    [[AND1:%.*]] = and i64 [[Y:%.*]], -9
; CHECK-NEXT:    [[AND1_Y:%.*]] = select i1 [[CMP]], i64 [[AND1]], i64 [[Y]]
; CHECK-NEXT:    ret i64 [[AND1_Y]]
;
  %and = and i32 %x, 8
  %cmp = icmp eq i32 %and, 0
  %and1 = and i64 %y, -9
  %and1.y = select i1 %cmp, i64 %and1, i64 %y
  ret i64 %and1.y
}

; Don't crash on a pointer or aggregate type.

define ptr @select_icmp_pointers(ptr %x, ptr %y) {
; CHECK-LABEL: @select_icmp_pointers(
; CHECK-NEXT:    [[CMP:%.*]] = icmp slt ptr [[X:%.*]], null
; CHECK-NEXT:    [[SEL:%.*]] = select i1 [[CMP]], ptr [[X]], ptr [[Y:%.*]]
; CHECK-NEXT:    ret ptr [[SEL]]
;
  %cmp = icmp slt ptr %x, null
  %sel = select i1 %cmp, ptr %x, ptr %y
  ret ptr %sel
}

; If the condition is known, we don't need to select, but we're not
; doing this fold here to avoid compile-time cost.

declare void @llvm.assume(i1)

define i8 @assume_sel_cond(i1 %cond, i8 %x, i8 %y) {
; CHECK-LABEL: @assume_sel_cond(
; CHECK-NEXT:    call void @llvm.assume(i1 [[COND:%.*]])
; CHECK-NEXT:    [[SEL:%.*]] = select i1 [[COND]], i8 [[X:%.*]], i8 [[Y:%.*]]
; CHECK-NEXT:    ret i8 [[SEL]]
;
  call void @llvm.assume(i1 %cond)
  %sel = select i1 %cond, i8 %x, i8 %y
  ret i8 %sel
}

define i8 @do_not_assume_sel_cond(i1 %cond, i8 %x, i8 %y) {
; CHECK-LABEL: @do_not_assume_sel_cond(
; CHECK-NEXT:    [[NOTCOND:%.*]] = icmp eq i1 [[COND:%.*]], false
; CHECK-NEXT:    call void @llvm.assume(i1 [[NOTCOND]])
; CHECK-NEXT:    [[SEL:%.*]] = select i1 [[COND]], i8 [[X:%.*]], i8 [[Y:%.*]]
; CHECK-NEXT:    ret i8 [[SEL]]
;
  %notcond = icmp eq i1 %cond, false
  call void @llvm.assume(i1 %notcond)
  %sel = select i1 %cond, i8 %x, i8 %y
  ret i8 %sel
}

define ptr @select_icmp_eq_0_gep_operand(ptr %base, i64 %n) {
; CHECK-LABEL: @select_icmp_eq_0_gep_operand(
; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i32, ptr [[BASE:%.*]], i64 [[N:%.*]]
; CHECK-NEXT:    ret ptr [[GEP]]
;
  %cond = icmp eq i64 %n, 0
  %gep = getelementptr i32, ptr %base, i64 %n
  %r = select i1 %cond, ptr %base, ptr %gep
  ret ptr %r
}

define ptr @select_icmp_ne_0_gep_operand(ptr %base, i64 %n) {
; CHECK-LABEL: @select_icmp_ne_0_gep_operand(
; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i32, ptr [[BASE:%.*]], i64 [[N:%.*]]
; CHECK-NEXT:    ret ptr [[GEP]]
;
  %cond = icmp ne i64 %n, 0
  %gep = getelementptr i32, ptr %base, i64 %n
  %r = select i1 %cond, ptr %gep, ptr %base
  ret ptr %r
}

define i1 @and_cmps(i32 %x) {
; CHECK-LABEL: @and_cmps(
; CHECK-NEXT:    [[CMP1:%.*]] = icmp slt i32 [[X:%.*]], 92
; CHECK-NEXT:    [[CMP2:%.*]] = icmp slt i32 [[X]], 11
; CHECK-NEXT:    [[R:%.*]] = select i1 [[CMP1]], i1 [[CMP2]], i1 false
; CHECK-NEXT:    ret i1 [[R]]
;
  %cmp1 = icmp slt i32 %x, 92
  %cmp2 = icmp slt i32 %x, 11
  %r = select i1 %cmp1, i1 %cmp2, i1 false
  ret i1 %r
}

define <2 x i1> @and_cmps_vector(<2 x i32> %x) {
; CHECK-LABEL: @and_cmps_vector(
; CHECK-NEXT:    [[CMP1:%.*]] = icmp slt <2 x i32> [[X:%.*]], <i32 92, i32 92>
; CHECK-NEXT:    [[CMP2:%.*]] = icmp slt <2 x i32> [[X]], <i32 11, i32 11>
; CHECK-NEXT:    [[R:%.*]] = select <2 x i1> [[CMP1]], <2 x i1> [[CMP2]], <2 x i1> zeroinitializer
; CHECK-NEXT:    ret <2 x i1> [[R]]
;
  %cmp1 = icmp slt <2 x i32> %x, <i32 92, i32 92>
  %cmp2 = icmp slt <2 x i32> %x, <i32 11, i32 11>
  %r = select <2 x i1> %cmp1, <2 x i1> %cmp2, <2 x i1> <i1 false, i1 false>
  ret <2 x i1> %r
}

define i1 @or_cmps(float %x) {
; CHECK-LABEL: @or_cmps(
; CHECK-NEXT:    [[CMP1:%.*]] = fcmp uno float [[X:%.*]], 4.200000e+01
; CHECK-NEXT:    [[CMP2:%.*]] = fcmp uno float [[X]], 5.200000e+01
; CHECK-NEXT:    [[R:%.*]] = select i1 [[CMP1]], i1 true, i1 [[CMP2]]
; CHECK-NEXT:    ret i1 [[R]]
;
  %cmp1 = fcmp uno float %x, 42.0
  %cmp2 = fcmp uno float %x, 52.0
  %r = select i1 %cmp1, i1 true, i1 %cmp2
  ret i1 %r
}

define <2 x i1> @or_logic_vector(<2 x i1> %x, <2 x i1> %y) {
; CHECK-LABEL: @or_logic_vector(
; CHECK-NEXT:    ret <2 x i1> [[X:%.*]]
;
  %a = and <2 x i1> %x, %y
  %r = select <2 x i1> %x, <2 x i1> <i1 true, i1 true>, <2 x i1> %a
  ret <2 x i1> %r
}

define i1 @and_not_cmps(i32 %x) {
; CHECK-LABEL: @and_not_cmps(
; CHECK-NEXT:    [[CMP1:%.*]] = icmp slt i32 [[X:%.*]], 92
; CHECK-NEXT:    [[CMP2:%.*]] = icmp slt i32 [[X]], 11
; CHECK-NEXT:    [[R:%.*]] = select i1 [[CMP1]], i1 false, i1 [[CMP2]]
; CHECK-NEXT:    ret i1 [[R]]
;
  %cmp1 = icmp slt i32 %x, 92
  %cmp2 = icmp slt i32 %x, 11
  %r = select i1 %cmp1, i1 false, i1 %cmp2
  ret i1 %r
}

define i1 @or_not_cmps(i32 %x) {
; CHECK-LABEL: @or_not_cmps(
; CHECK-NEXT:    [[CMP1:%.*]] = icmp slt i32 [[X:%.*]], 92
; CHECK-NEXT:    [[CMP2:%.*]] = icmp slt i32 [[X]], 11
; CHECK-NEXT:    [[R:%.*]] = select i1 [[CMP1]], i1 [[CMP2]], i1 true
; CHECK-NEXT:    ret i1 [[R]]
;
  %cmp1 = icmp slt i32 %x, 92
  %cmp2 = icmp slt i32 %x, 11
  %r = select i1 %cmp1, i1 %cmp2, i1 true
  ret i1 %r
}

define i8 @and_cmps_wrong_type(i32 %x) {
; CHECK-LABEL: @and_cmps_wrong_type(
; CHECK-NEXT:    [[CMP1:%.*]] = icmp slt i32 [[X:%.*]], 92
; CHECK-NEXT:    [[CMP2:%.*]] = icmp slt i32 [[X]], 11
; CHECK-NEXT:    [[S:%.*]] = sext i1 [[CMP2]] to i8
; CHECK-NEXT:    [[R:%.*]] = select i1 [[CMP1]], i8 [[S]], i8 0
; CHECK-NEXT:    ret i8 [[R]]
;
  %cmp1 = icmp slt i32 %x, 92
  %cmp2 = icmp slt i32 %x, 11
  %s = sext i1 %cmp2 to i8
  %r = select i1 %cmp1, i8 %s, i8 0
  ret i8 %r
}

define i1 @y_might_be_poison(float %x, float %y) {
; CHECK-LABEL: @y_might_be_poison(
; CHECK-NEXT:    [[C1:%.*]] = fcmp ord float 0.000000e+00, [[X:%.*]]
; CHECK-NEXT:    [[C2:%.*]] = fcmp ord float [[X]], [[Y:%.*]]
; CHECK-NEXT:    [[C3:%.*]] = select i1 [[C1]], i1 [[C2]], i1 false
; CHECK-NEXT:    ret i1 [[C3]]
;
  %c1 = fcmp ord float 0.0, %x
  %c2 = fcmp ord float %x, %y
  %c3 = select i1 %c1, i1 %c2, i1 false
  ret i1 %c3
}

; Negative tests to ensure we don't remove selects with undef true/false values.
; See https://bugs.llvm.org/show_bug.cgi?id=31633
; https://lists.llvm.org/pipermail/llvm-dev/2016-October/106182.html
; https://reviews.llvm.org/D83360
define i32 @false_undef(i1 %cond, i32 %x) {
; CHECK-LABEL: @false_undef(
; CHECK-NEXT:    [[S:%.*]] = select i1 [[COND:%.*]], i32 [[X:%.*]], i32 undef
; CHECK-NEXT:    ret i32 [[S]]
;
  %s = select i1 %cond, i32 %x, i32 undef
  ret i32 %s
}

define i32 @true_undef(i1 %cond, i32 %x) {
; CHECK-LABEL: @true_undef(
; CHECK-NEXT:    [[S:%.*]] = select i1 [[COND:%.*]], i32 undef, i32 [[X:%.*]]
; CHECK-NEXT:    ret i32 [[S]]
;
  %s = select i1 %cond, i32 undef, i32 %x
  ret i32 %s
}

define <2 x i32> @false_undef_vec(i1 %cond, <2 x i32> %x) {
; CHECK-LABEL: @false_undef_vec(
; CHECK-NEXT:    [[S:%.*]] = select i1 [[COND:%.*]], <2 x i32> [[X:%.*]], <2 x i32> undef
; CHECK-NEXT:    ret <2 x i32> [[S]]
;
  %s = select i1 %cond, <2 x i32> %x, <2 x i32> undef
  ret <2 x i32> %s
}

define <2 x i32> @true_undef_vec(i1 %cond, <2 x i32> %x) {
; CHECK-LABEL: @true_undef_vec(
; CHECK-NEXT:    [[S:%.*]] = select i1 [[COND:%.*]], <2 x i32> undef, <2 x i32> [[X:%.*]]
; CHECK-NEXT:    ret <2 x i32> [[S]]
;
  %s = select i1 %cond, <2 x i32> undef, <2 x i32> %x
  ret <2 x i32> %s
}

; These can be folded because the other value is guaranteed not to be poison.
define i32 @false_undef_true_constant(i1 %cond) {
; CHECK-LABEL: @false_undef_true_constant(
; CHECK-NEXT:    ret i32 10
;
  %s = select i1 %cond, i32 10, i32 undef
  ret i32 %s
}

define i32 @true_undef_false_constant(i1 %cond) {
; CHECK-LABEL: @true_undef_false_constant(
; CHECK-NEXT:    ret i32 20
;
  %s = select i1 %cond, i32 undef, i32 20
  ret i32 %s
}

define <2 x i32> @false_undef_true_constant_vec(i1 %cond) {
; CHECK-LABEL: @false_undef_true_constant_vec(
; CHECK-NEXT:    ret <2 x i32> <i32 42, i32 -42>
;
  %s = select i1 %cond, <2 x i32> <i32 42, i32 -42>, <2 x i32> undef
  ret <2 x i32> %s
}

define <2 x i32> @true_undef_false_constant_vec(i1 %cond) {
; CHECK-LABEL: @true_undef_false_constant_vec(
; CHECK-NEXT:    ret <2 x i32> <i32 -42, i32 42>
;
  %s = select i1 %cond, <2 x i32> undef, <2 x i32> <i32 -42, i32 42>
  ret <2 x i32> %s
}

; If one input is undef and the other is freeze, we can fold it to the freeze.
define i32 @false_undef_true_freeze(i1 %cond, i32 %x) {
; CHECK-LABEL: @false_undef_true_freeze(
; CHECK-NEXT:    [[XF:%.*]] = freeze i32 [[X:%.*]]
; CHECK-NEXT:    ret i32 [[XF]]
;
  %xf = freeze i32 %x
  %s = select i1 %cond, i32 %xf, i32 undef
  ret i32 %s
}

define i32 @false_undef_false_freeze(i1 %cond, i32 %x) {
; CHECK-LABEL: @false_undef_false_freeze(
; CHECK-NEXT:    [[XF:%.*]] = freeze i32 [[X:%.*]]
; CHECK-NEXT:    ret i32 [[XF]]
;
  %xf = freeze i32 %x
  %s = select i1 %cond, i32 undef, i32 %xf
  ret i32 %s
}

@g = external global i32, align 1

define <2 x i32> @false_undef_true_constextpr_vec(i1 %cond) {
; CHECK-LABEL: @false_undef_true_constextpr_vec(
; CHECK-NEXT:    ret <2 x i32> <i32 ptrtoint (ptr @g to i32), i32 ptrtoint (ptr @g to i32)>
;
  %s = select i1 %cond, <2 x i32> <i32 undef, i32 ptrtoint (ptr @g to i32)>, <2 x i32> <i32 ptrtoint (ptr @g to i32), i32 undef>
  ret <2 x i32> %s
}

define i32 @all_constant_true_undef() {
; CHECK-LABEL: @all_constant_true_undef(
; CHECK-NEXT:    ret i32 1
;
  %s = select i1 ptrtoint (ptr @all_constant_true_undef to i1), i32 undef, i32 1
  ret i32 %s
}

define float @all_constant_false_undef() {
; CHECK-LABEL: @all_constant_false_undef(
; CHECK-NEXT:    ret float 1.000000e+00
;
  %s = select i1 ptrtoint (ptr @all_constant_false_undef to i1), float undef, float 1.0
  ret float %s
}

define <2 x i32> @all_constant_true_undef_vec() {
; CHECK-LABEL: @all_constant_true_undef_vec(
; CHECK-NEXT:    ret <2 x i32> <i32 1, i32 -1>
;
  %s = select i1 ptrtoint (ptr @all_constant_true_undef_vec to i1), <2 x i32> undef, <2 x i32> <i32 1, i32 -1>
  ret <2 x i32> %s
}

define <2 x float> @all_constant_false_undef_vec() {
; CHECK-LABEL: @all_constant_false_undef_vec(
; CHECK-NEXT:    ret <2 x float> <float 1.000000e+00, float -1.000000e+00>
;
  %s = select i1 ptrtoint (ptr @all_constant_false_undef_vec to i1), <2 x float> undef, <2 x float> <float 1.0, float -1.0>
  ret <2 x float> %s
}

; Negative tests. Don't fold if the non-undef operand is a constexpr.
define i32 @all_constant_false_undef_true_constexpr() {
; CHECK-LABEL: @all_constant_false_undef_true_constexpr(
; CHECK-NEXT:    ret i32 ptrtoint (ptr @all_constant_false_undef_true_constexpr to i32)
;
  %s = select i1 ptrtoint (ptr @all_constant_false_undef_true_constexpr to i1), i32 ptrtoint (ptr @all_constant_false_undef_true_constexpr to i32), i32 undef
  ret i32 %s
}

define i32 @all_constant_true_undef_false_constexpr() {
; CHECK-LABEL: @all_constant_true_undef_false_constexpr(
; CHECK-NEXT:    ret i32 ptrtoint (ptr @all_constant_true_undef_false_constexpr to i32)
;
  %s = select i1 ptrtoint (ptr @all_constant_true_undef_false_constexpr to i1), i32 undef, i32 ptrtoint (ptr @all_constant_true_undef_false_constexpr to i32)
  ret i32 %s
}

; Negative tests. Don't fold if the non-undef operand is a vector containing a constexpr.
define <2 x i32> @all_constant_false_undef_true_constexpr_vec() {
; CHECK-LABEL: @all_constant_false_undef_true_constexpr_vec(
; CHECK-NEXT:    ret <2 x i32> <i32 ptrtoint (ptr @all_constant_false_undef_true_constexpr_vec to i32), i32 -1>
;
  %s = select i1 ptrtoint (ptr @all_constant_false_undef_true_constexpr_vec to i1), <2 x i32> <i32 ptrtoint (ptr @all_constant_false_undef_true_constexpr_vec to i32), i32 -1>, <2 x i32> undef
  ret <2 x i32> %s
}

define <2 x i32> @all_constant_true_undef_false_constexpr_vec() {
; CHECK-LABEL: @all_constant_true_undef_false_constexpr_vec(
; CHECK-NEXT:    ret <2 x i32> <i32 -1, i32 ptrtoint (ptr @all_constant_true_undef_false_constexpr_vec to i32)>
;
  %s = select i1 ptrtoint (ptr @all_constant_true_undef_false_constexpr_vec to i1), <2 x i32> undef, <2 x i32><i32 -1, i32 ptrtoint (ptr @all_constant_true_undef_false_constexpr_vec to i32)>
  ret <2 x i32> %s
}

define i1 @expand_binop_undef(i32 %x, i32 %y) {
; CHECK-LABEL: @expand_binop_undef(
; CHECK-NEXT:    [[CMP9_NOT_1:%.*]] = icmp eq i32 [[X:%.*]], [[Y:%.*]]
; CHECK-NEXT:    [[CMP15:%.*]] = icmp slt i32 [[X]], [[Y]]
; CHECK-NEXT:    [[SPEC_SELECT39:%.*]] = select i1 [[CMP9_NOT_1]], i1 undef, i1 [[CMP15]]
; CHECK-NEXT:    [[SPEC_SELECT40:%.*]] = xor i1 [[CMP9_NOT_1]], true
; CHECK-NEXT:    [[SPEC_SELECT:%.*]] = and i1 [[SPEC_SELECT39]], [[SPEC_SELECT40]]
; CHECK-NEXT:    ret i1 [[SPEC_SELECT]]
;
  %cmp9.not.1 = icmp eq i32 %x, %y
  %cmp15 = icmp slt i32 %x, %y
  %spec.select39 = select i1 %cmp9.not.1, i1 undef, i1 %cmp15
  %spec.select40 = xor i1 %cmp9.not.1, 1
  %spec.select  = and i1 %spec.select39, %spec.select40
  ret i1 %spec.select
}

define i32 @pr47322_more_poisonous_replacement(i32 %arg) {
; CHECK-LABEL: @pr47322_more_poisonous_replacement(
; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i32 [[ARG:%.*]], 0
; CHECK-NEXT:    [[TRAILING:%.*]] = call i32 @llvm.cttz.i32(i32 [[ARG]], i1 immarg true)
; CHECK-NEXT:    [[SHIFTED:%.*]] = lshr i32 [[ARG]], [[TRAILING]]
; CHECK-NEXT:    [[R1_SROA_0_1:%.*]] = select i1 [[CMP]], i32 0, i32 [[SHIFTED]]
; CHECK-NEXT:    ret i32 [[R1_SROA_0_1]]
;
  %cmp = icmp eq i32 %arg, 0
  %trailing = call i32 @llvm.cttz.i32(i32 %arg, i1 immarg true)
  %shifted = lshr i32 %arg, %trailing
  %r1.sroa.0.1 = select i1 %cmp, i32 0, i32 %shifted
  ret i32 %r1.sroa.0.1
}
declare i32 @llvm.cttz.i32(i32, i1 immarg)

; Partial undef scalable vectors should be ignored.
define <vscale x 2 x i1> @ignore_scalable_undef(<vscale x 2 x i1> %cond) {
; CHECK-LABEL: @ignore_scalable_undef(
; CHECK-NEXT:    ret <vscale x 2 x i1> insertelement (<vscale x 2 x i1> undef, i1 true, i32 0)
;
  %vec = insertelement <vscale x 2 x i1> undef, i1 true, i32 0
  %s = select <vscale x 2 x i1> %cond, <vscale x 2 x i1> undef, <vscale x 2 x i1> %vec
  ret <vscale x 2 x i1> %s
}

define i32 @select_neutral_add_rhs(i32 %x, i32 %y) {
; CHECK-LABEL: @select_neutral_add_rhs(
; CHECK-NEXT:    [[ADD:%.*]] = add i32 [[X:%.*]], [[Y:%.*]]
; CHECK-NEXT:    ret i32 [[ADD]]
;
  %cmp = icmp ne i32 %y, 0
  %add = add i32 %x, %y
  %sel = select i1 %cmp, i32 %add, i32 %x
  ret i32 %sel
}

define i32 @select_neutral_add_lhs(i32 %x, i32 %y) {
; CHECK-LABEL: @select_neutral_add_lhs(
; CHECK-NEXT:    [[ADD:%.*]] = add i32 [[Y:%.*]], [[X:%.*]]
; CHECK-NEXT:    ret i32 [[ADD]]
;
  %cmp = icmp ne i32 %y, 0
  %add = add i32 %y, %x
  %sel = select i1 %cmp, i32 %add, i32 %x
  ret i32 %sel
}

define <2 x i32> @select_neutral_add_rhs_vec(<2 x i32> %x, <2 x i32> %y) {
; CHECK-LABEL: @select_neutral_add_rhs_vec(
; CHECK-NEXT:    [[ADD:%.*]] = add <2 x i32> [[X:%.*]], [[Y:%.*]]
; CHECK-NEXT:    ret <2 x i32> [[ADD]]
;
  %cmp = icmp ne <2 x i32> %y, zeroinitializer
  %add = add <2 x i32> %x, %y
  %sel = select <2 x i1> %cmp, <2 x i32> %add, <2 x i32> %x
  ret <2 x i32> %sel
}

define <2 x i32> @select_neutral_add_lhs_vec(<2 x i32> %x, <2 x i32> %y) {
; CHECK-LABEL: @select_neutral_add_lhs_vec(
; CHECK-NEXT:    [[ADD:%.*]] = add <2 x i32> [[Y:%.*]], [[X:%.*]]
; CHECK-NEXT:    ret <2 x i32> [[ADD]]
;
  %cmp = icmp ne <2 x i32> %y, zeroinitializer
  %add = add <2 x i32> %y, %x
  %sel = select <2 x i1> %cmp, <2 x i32> %add, <2 x i32> %x
  ret <2 x i32> %sel
}

define i32 @select_neutral_sub_rhs(i32 %x, i32 %y) {
; CHECK-LABEL: @select_neutral_sub_rhs(
; CHECK-NEXT:    [[ADD:%.*]] = sub i32 [[X:%.*]], [[Y:%.*]]
; CHECK-NEXT:    ret i32 [[ADD]]
;
  %cmp = icmp ne i32 %y, 0
  %add = sub i32 %x, %y
  %sel = select i1 %cmp, i32 %add, i32 %x
  ret i32 %sel
}

define i32 @select_neutral_sub_lhs(i32 %x, i32 %y) {
; CHECK-LABEL: @select_neutral_sub_lhs(
; CHECK-NEXT:    [[CMP:%.*]] = icmp ne i32 [[Y:%.*]], 0
; CHECK-NEXT:    [[ADD:%.*]] = sub i32 [[Y]], [[X:%.*]]
; CHECK-NEXT:    [[SEL:%.*]] = select i1 [[CMP]], i32 [[ADD]], i32 [[X]]
; CHECK-NEXT:    ret i32 [[SEL]]
;
  %cmp = icmp ne i32 %y, 0
  %add = sub i32 %y, %x
  %sel = select i1 %cmp, i32 %add, i32 %x
  ret i32 %sel
}

define i32 @select_ctpop_zero(i32 %x) {
; CHECK-LABEL: @select_ctpop_zero(
; CHECK-NEXT:    [[T1:%.*]] = call i32 @llvm.ctpop.i32(i32 [[X:%.*]])
; CHECK-NEXT:    ret i32 [[T1]]
;
  %t0 = icmp eq i32 %x, 0
  %t1 = call i32 @llvm.ctpop.i32(i32 %x)
  %sel = select i1 %t0, i32 0, i32 %t1
  ret i32 %sel
}

; FIXME: This is safe to fold.
define <2 x i32> @select_ctpop_zero_vec(<2 x i32> %x) {
; CHECK-LABEL: @select_ctpop_zero_vec(
; CHECK-NEXT:    [[T0:%.*]] = icmp eq <2 x i32> [[X:%.*]], zeroinitializer
; CHECK-NEXT:    [[T1:%.*]] = call <2 x i32> @llvm.ctpop.v2i32(<2 x i32> [[X]])
; CHECK-NEXT:    [[SEL:%.*]] = select <2 x i1> [[T0]], <2 x i32> zeroinitializer, <2 x i32> [[T1]]
; CHECK-NEXT:    ret <2 x i32> [[SEL]]
;
  %t0 = icmp eq <2 x i32> %x, zeroinitializer
  %t1 = call <2 x i32> @llvm.ctpop.v2i32(<2 x i32> %x)
  %sel = select <2 x i1> %t0, <2 x i32> zeroinitializer, <2 x i32> %t1
  ret <2 x i32> %sel
}

; Negative test: Cannot fold due to cross-lane intrinsic.
define <2 x i32> @select_vector_reverse(<2 x i32> %x) {
; CHECK-LABEL: @select_vector_reverse(
; CHECK-NEXT:    [[CMP:%.*]] = icmp eq <2 x i32> [[X:%.*]], zeroinitializer
; CHECK-NEXT:    [[REV:%.*]] = call <2 x i32> @llvm.experimental.vector.reverse.v2i32(<2 x i32> [[X]])
; CHECK-NEXT:    [[SEL:%.*]] = select <2 x i1> [[CMP]], <2 x i32> zeroinitializer, <2 x i32> [[REV]]
; CHECK-NEXT:    ret <2 x i32> [[SEL]]
;
  %cmp = icmp eq <2 x i32> %x, zeroinitializer
  %rev = call <2 x i32> @llvm.experimental.vector.reverse.v2i32(<2 x i32> %x)
  %sel = select <2 x i1> %cmp, <2 x i32> zeroinitializer, <2 x i32> %rev
  ret <2 x i32> %sel
}

declare i32 @llvm.ctpop.i32(i32)
declare <2 x i32> @llvm.ctpop.v2i32(<2 x i32>)
declare <2 x i32> @llvm.experimental.vector.reverse.v2i32(<2 x i32>)

define <2 x i32> @vec_select_no_equivalence(<2 x i32> %x, <2 x i32> %y) {
; CHECK-LABEL: @vec_select_no_equivalence(
; CHECK-NEXT:    [[X10:%.*]] = shufflevector <2 x i32> [[X:%.*]], <2 x i32> undef, <2 x i32> <i32 1, i32 0>
; CHECK-NEXT:    [[COND:%.*]] = icmp eq <2 x i32> [[X]], zeroinitializer
; CHECK-NEXT:    [[S:%.*]] = select <2 x i1> [[COND]], <2 x i32> [[X10]], <2 x i32> zeroinitializer
; CHECK-NEXT:    ret <2 x i32> [[S]]
;
  %x10 = shufflevector <2 x i32> %x, <2 x i32> undef, <2 x i32> <i32 1, i32 0>
  %cond = icmp eq <2 x i32> %x, zeroinitializer
  %s = select <2 x i1> %cond, <2 x i32> %x10, <2 x i32> zeroinitializer
  ret <2 x i32> %s
}

define i8 @select_eq_xor_recursive(i8 %a, i8 %b) {
; CHECK-LABEL: @select_eq_xor_recursive(
; CHECK-NEXT:    [[XOR:%.*]] = xor i8 [[A:%.*]], [[B:%.*]]
; CHECK-NEXT:    [[INV:%.*]] = xor i8 [[XOR]], -1
; CHECK-NEXT:    ret i8 [[INV]]
;
  %xor = xor i8 %a, %b
  %inv = xor i8 %xor, -1
  %cmp = icmp eq i8 %a, %b
  %sel = select i1 %cmp, i8 -1, i8 %inv
  ret i8 %sel
}

define i8 @select_eq_xor_recursive2(i8 %a, i8 %b) {
; CHECK-LABEL: @select_eq_xor_recursive2(
; CHECK-NEXT:    [[XOR:%.*]] = xor i8 [[A:%.*]], [[B:%.*]]
; CHECK-NEXT:    [[INV:%.*]] = xor i8 [[XOR]], -1
; CHECK-NEXT:    [[ADD:%.*]] = add i8 [[INV]], 10
; CHECK-NEXT:    ret i8 [[ADD]]
;
  %xor = xor i8 %a, %b
  %inv = xor i8 %xor, -1
  %add = add i8 %inv, 10
  %cmp = icmp eq i8 %a, %b
  %sel = select i1 %cmp, i8 9, i8 %add
  ret i8 %sel
}

define i8 @select_eq_xor_recursive3(i8 %a, i8 %b) {
; CHECK-LABEL: @select_eq_xor_recursive3(
; CHECK-NEXT:    [[XOR:%.*]] = xor i8 [[A:%.*]], [[B:%.*]]
; CHECK-NEXT:    [[INV:%.*]] = xor i8 [[XOR]], -1
; CHECK-NEXT:    [[ADD:%.*]] = add i8 [[INV]], 10
; CHECK-NEXT:    [[MUL:%.*]] = mul i8 [[ADD]], 3
; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i8 [[A]], [[B]]
; CHECK-NEXT:    [[SEL:%.*]] = select i1 [[CMP]], i8 9, i8 [[MUL]]
; CHECK-NEXT:    ret i8 [[SEL]]
;
  %xor = xor i8 %a, %b
  %inv = xor i8 %xor, -1
  %add = add i8 %inv, 10
  %mul = mul i8 %add, 3
  %cmp = icmp eq i8 %a, %b
  %sel = select i1 %cmp, i8 9, i8 %mul
  ret i8 %sel
}

; Cannot drop select, because this would propagate poison from %a.
define i8 @select_eq_xor_recursive_propagates_poison(i8 %a, i8 %b) {
; CHECK-LABEL: @select_eq_xor_recursive_propagates_poison(
; CHECK-NEXT:    [[XOR1:%.*]] = add i8 [[A:%.*]], [[B:%.*]]
; CHECK-NEXT:    [[XOR2:%.*]] = xor i8 [[A]], [[XOR1]]
; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i8 [[B]], 0
; CHECK-NEXT:    [[SEL:%.*]] = select i1 [[CMP]], i8 0, i8 [[XOR2]]
; CHECK-NEXT:    ret i8 [[SEL]]
;
  %xor1 = add i8 %a, %b
  %xor2 = xor i8 %a, %xor1
  %cmp = icmp eq i8 %b, 0
  %sel = select i1 %cmp, i8 0, i8 %xor2
  ret i8 %sel
}

define i8 @select_eq_and_recursive(i8 %a) {
; CHECK-LABEL: @select_eq_and_recursive(
; CHECK-NEXT:    [[NEG:%.*]] = sub i8 0, [[A:%.*]]
; CHECK-NEXT:    [[AND:%.*]] = and i8 [[NEG]], [[A]]
; CHECK-NEXT:    [[ADD:%.*]] = add i8 [[AND]], 1
; CHECK-NEXT:    ret i8 [[ADD]]
;
  %neg = sub i8 0, %a
  %and = and i8 %neg, %a
  %add = add i8 %and, 1
  %cmp = icmp eq i8 %a, 0
  %sel = select i1 %cmp, i8 1, i8 %add
  ret i8 %sel
}

; Cannot drop select, because this would propagate poison from %b.
define i8 @select_eq_and_recursive_propagates_poison(i8 %a, i8 %b) {
; CHECK-LABEL: @select_eq_and_recursive_propagates_poison(
; CHECK-NEXT:    [[NEG:%.*]] = sub i8 [[B:%.*]], [[A:%.*]]
; CHECK-NEXT:    [[AND:%.*]] = and i8 [[NEG]], [[A]]
; CHECK-NEXT:    [[ADD:%.*]] = add i8 [[AND]], 1
; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i8 [[A]], 0
; CHECK-NEXT:    [[SEL:%.*]] = select i1 [[CMP]], i8 1, i8 [[ADD]]
; CHECK-NEXT:    ret i8 [[SEL]]
;
  %neg = sub i8 %b, %a
  %and = and i8 %neg, %a
  %add = add i8 %and, 1
  %cmp = icmp eq i8 %a, 0
  %sel = select i1 %cmp, i8 1, i8 %add
  ret i8 %sel
}

define i8 @select_eq_xor_recursive_allow_refinement(i8 %a, i8 %b) {
; CHECK-LABEL: @select_eq_xor_recursive_allow_refinement(
; CHECK-NEXT:    ret i8 0
;
  %xor1 = add i8 %a, %b
  %xor2 = xor i8 %a, %xor1
  %cmp = icmp eq i8 %b, 0
  %sel = select i1 %cmp, i8 %xor2, i8 0
  ret i8 %sel
}

define i8 @select_eq_mul_absorber(i8 %x, i8 noundef %y) {
; CHECK-LABEL: @select_eq_mul_absorber(
; CHECK-NEXT:    [[ADD:%.*]] = add i8 [[X:%.*]], -1
; CHECK-NEXT:    [[MUL:%.*]] = mul i8 [[ADD]], [[Y:%.*]]
; CHECK-NEXT:    ret i8 [[MUL]]
;
  %cmp = icmp eq i8 %x, 1
  %add = add i8 %x, -1
  %mul = mul i8 %add, %y
  %sel = select i1 %cmp, i8 0, i8 %mul
  ret i8 %sel
}

define i8 @select_eq_mul_not_absorber(i8 %x, i8 noundef %y) {
; CHECK-LABEL: @select_eq_mul_not_absorber(
; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i8 [[X:%.*]], 0
; CHECK-NEXT:    [[ADD:%.*]] = add i8 [[X]], -1
; CHECK-NEXT:    [[MUL:%.*]] = mul i8 [[ADD]], [[Y:%.*]]
; CHECK-NEXT:    [[SEL:%.*]] = select i1 [[CMP]], i8 0, i8 [[MUL]]
; CHECK-NEXT:    ret i8 [[SEL]]
;
  %cmp = icmp eq i8 %x, 0
  %add = add i8 %x, -1
  %mul = mul i8 %add, %y
  %sel = select i1 %cmp, i8 0, i8 %mul
  ret i8 %sel
}

; Vector to scalar options should be treated as lane-crossing.
define <2 x i8> @select_eq_vector_insert_extract(<2 x i8> %a, <2 x i8> %b) {
; CHECK-LABEL: @select_eq_vector_insert_extract(
; CHECK-NEXT:    [[EXTRACT0:%.*]] = extractelement <2 x i8> [[A:%.*]], i64 0
; CHECK-NEXT:    [[EXTRACT1:%.*]] = extractelement <2 x i8> [[A]], i64 1
; CHECK-NEXT:    [[INSERT0:%.*]] = insertelement <2 x i8> poison, i8 [[EXTRACT1]], i64 0
; CHECK-NEXT:    [[INSERT1:%.*]] = insertelement <2 x i8> [[INSERT0]], i8 [[EXTRACT0]], i64 1
; CHECK-NEXT:    [[CMP:%.*]] = icmp eq <2 x i8> [[A]], zeroinitializer
; CHECK-NEXT:    [[SEL:%.*]] = select <2 x i1> [[CMP]], <2 x i8> [[INSERT1]], <2 x i8> zeroinitializer
; CHECK-NEXT:    ret <2 x i8> [[SEL]]
;
  %extract0 = extractelement <2 x i8> %a, i64 0
  %extract1 = extractelement <2 x i8> %a, i64 1
  %insert0 = insertelement <2 x i8> poison, i8 %extract1, i64 0
  %insert1 = insertelement <2 x i8> %insert0, i8 %extract0, i64 1
  %cmp = icmp eq <2 x i8> %a, zeroinitializer
  %sel = select <2 x i1> %cmp, <2 x i8> %insert1, <2 x i8> zeroinitializer
  ret <2 x i8> %sel
}

define i32 @poison(i32 %x, i32 %y) {
; CHECK-LABEL: @poison(
; CHECK-NEXT:    ret i32 [[X:%.*]]
;
  %v = select i1 undef, i32 %x, i32 %y
  ret i32 %v
}

define i32 @poison2(i1 %cond, i32 %x) {
; CHECK-LABEL: @poison2(
; CHECK-NEXT:    ret i32 [[X:%.*]]
;
  %v = select i1 %cond, i32 poison, i32 %x
  ret i32 %v
}

define i32 @poison3(i1 %cond, i32 %x) {
; CHECK-LABEL: @poison3(
; CHECK-NEXT:    ret i32 [[X:%.*]]
;
  %v = select i1 %cond, i32 %x, i32 poison
  ret i32 %v
}

define <2 x i32> @poison4(<2 x i1> %cond, <2 x i32> %x) {
; CHECK-LABEL: @poison4(
; CHECK-NEXT:    ret <2 x i32> [[X:%.*]]
;
  %v = select <2 x i1> %cond, <2 x i32> %x, <2 x i32> poison
  ret <2 x i32> %v
}

; 0 is the absorber constant for 'and'.
; The 'select' can't block extra poison because both sides of 'and' have 'x' operand.

define i8 @replace_false_op_eq_neg_and(i8 %x) {
; CHECK-LABEL: @replace_false_op_eq_neg_and(
; CHECK-NEXT:    [[NEG:%.*]] = sub i8 0, [[X:%.*]]
; CHECK-NEXT:    [[AND:%.*]] = and i8 [[NEG]], [[X]]
; CHECK-NEXT:    ret i8 [[AND]]
;
  %eq0 = icmp eq i8 %x, 0
  %neg = sub i8 0, %x
  %and = and i8 %neg, %x
  %sel = select i1 %eq0, i8 0, i8 %and
  ret i8 %sel
}

; same as above, but commute 'and'

define i8 @replace_false_op_eq_neg_and_commute(i8 %x) {
; CHECK-LABEL: @replace_false_op_eq_neg_and_commute(
; CHECK-NEXT:    [[NEG:%.*]] = sub i8 0, [[X:%.*]]
; CHECK-NEXT:    [[AND:%.*]] = and i8 [[X]], [[NEG]]
; CHECK-NEXT:    ret i8 [[AND]]
;
  %eq0 = icmp eq i8 %x, 0
  %neg = sub i8 0, %x
  %and = and i8 %x, %neg
  %sel = select i1 %eq0, i8 0, i8 %and
  ret i8 %sel
}

; same as above, but swap 'select'

define i8 @replace_false_op_ne_neg_and(i8 %x) {
; CHECK-LABEL: @replace_false_op_ne_neg_and(
; CHECK-NEXT:    [[NEG:%.*]] = sub i8 0, [[X:%.*]]
; CHECK-NEXT:    [[AND:%.*]] = and i8 [[NEG]], [[X]]
; CHECK-NEXT:    ret i8 [[AND]]
;
  %ne0 = icmp ne i8 %x, 0
  %neg = sub i8 0, %x
  %and = and i8 %neg, %x
  %sel = select i1 %ne0, i8 %and, i8 0
  ret i8 %sel
}

; same as above, but commute 'and' and swap 'select'

define i8 @replace_false_op_ne_neg_and_commute(i8 %x) {
; CHECK-LABEL: @replace_false_op_ne_neg_and_commute(
; CHECK-NEXT:    [[NEG:%.*]] = sub i8 0, [[X:%.*]]
; CHECK-NEXT:    [[AND:%.*]] = and i8 [[X]], [[NEG]]
; CHECK-NEXT:    ret i8 [[AND]]
;
  %ne0 = icmp ne i8 %x, 0
  %neg = sub i8 0, %x
  %and = and i8 %x, %neg
  %sel = select i1 %ne0, i8 %and, i8 0
  ret i8 %sel
}

; the first binop can be anything as long as it has the common operand

define i8 @replace_false_op_eq_dec_and(i8 %x) {
; CHECK-LABEL: @replace_false_op_eq_dec_and(
; CHECK-NEXT:    [[DEC:%.*]] = add i8 [[X:%.*]], -1
; CHECK-NEXT:    [[AND:%.*]] = and i8 [[DEC]], [[X]]
; CHECK-NEXT:    ret i8 [[AND]]
;
  %eq0 = icmp eq i8 %x, 0
  %dec = add i8 %x, -1
  %and = and i8 %dec, %x
  %sel = select i1 %eq0, i8 0, i8 %and
  ret i8 %sel
}

; mul has the same absorber constant - "0"

define i8 @replace_false_op_eq_add_mul(i8 %x) {
; CHECK-LABEL: @replace_false_op_eq_add_mul(
; CHECK-NEXT:    [[ADD:%.*]] = add i8 [[X:%.*]], 42
; CHECK-NEXT:    [[MUL:%.*]] = mul i8 [[ADD]], [[X]]
; CHECK-NEXT:    ret i8 [[MUL]]
;
  %eq0 = icmp eq i8 %x, 0
  %add = add i8 %x, 42
  %mul = mul i8 %add, %x
  %sel = select i1 %eq0, i8 0, i8 %mul
  ret i8 %sel
}

; or has a different absorber constant = "-1"

define i8 @replace_false_op_eq_shl_or(i8 %x) {
; CHECK-LABEL: @replace_false_op_eq_shl_or(
; CHECK-NEXT:    [[SHL:%.*]] = shl i8 [[X:%.*]], 3
; CHECK-NEXT:    [[OR:%.*]] = or i8 [[X]], [[SHL]]
; CHECK-NEXT:    ret i8 [[OR]]
;
  %eq0 = icmp eq i8 %x, -1
  %shl = shl i8 %x, 3
  %or = or i8 %x, %shl
  %sel = select i1 %eq0, i8 -1, i8 %or
  ret i8 %sel
}

; negative test - wrong cmp predicate

define i8 @replace_false_op_sgt_neg_and(i8 %x) {
; CHECK-LABEL: @replace_false_op_sgt_neg_and(
; CHECK-NEXT:    [[EQ0:%.*]] = icmp sgt i8 [[X:%.*]], 0
; CHECK-NEXT:    [[NEG:%.*]] = sub i8 0, [[X]]
; CHECK-NEXT:    [[AND:%.*]] = and i8 [[NEG]], [[X]]
; CHECK-NEXT:    [[SEL:%.*]] = select i1 [[EQ0]], i8 0, i8 [[AND]]
; CHECK-NEXT:    ret i8 [[SEL]]
;
  %eq0 = icmp sgt i8 %x, 0
  %neg = sub i8 0, %x
  %and = and i8 %neg, %x
  %sel = select i1 %eq0, i8 0, i8 %and
  ret i8 %sel
}

; negative test - the binop must use a compare operand

define i8 @replace_false_op_eq_shl_or_wrong_cmp_op(i8 %x, i8 %y) {
; CHECK-LABEL: @replace_false_op_eq_shl_or_wrong_cmp_op(
; CHECK-NEXT:    [[EQ0:%.*]] = icmp eq i8 [[Y:%.*]], -1
; CHECK-NEXT:    [[SHL:%.*]] = shl i8 [[X:%.*]], 3
; CHECK-NEXT:    [[OR:%.*]] = or i8 [[X]], [[SHL]]
; CHECK-NEXT:    [[SEL:%.*]] = select i1 [[EQ0]], i8 -1, i8 [[OR]]
; CHECK-NEXT:    ret i8 [[SEL]]
;
  %eq0 = icmp eq i8 %y, -1
  %shl = shl i8 %x, 3
  %or = or i8 %x, %shl
  %sel = select i1 %eq0, i8 -1, i8 %or
  ret i8 %sel
}

; negative test - can't have extra source of potential poison

define i8 @replace_false_op_eq_neg_and_leak1(i8 %x, i8 %y) {
; CHECK-LABEL: @replace_false_op_eq_neg_and_leak1(
; CHECK-NEXT:    [[EQ0:%.*]] = icmp eq i8 [[X:%.*]], 0
; CHECK-NEXT:    [[NEG:%.*]] = sub i8 0, [[Y:%.*]]
; CHECK-NEXT:    [[AND:%.*]] = and i8 [[NEG]], [[X]]
; CHECK-NEXT:    [[SEL:%.*]] = select i1 [[EQ0]], i8 0, i8 [[AND]]
; CHECK-NEXT:    ret i8 [[SEL]]
;
  %eq0 = icmp eq i8 %x, 0
  %neg = sub i8 0, %y
  %and = and i8 %neg, %x
  %sel = select i1 %eq0, i8 0, i8 %and
  ret i8 %sel
}

; negative test - can't have extra source of potential poison

define i8 @replace_false_op_eq_neg_and_leak2(i8 %x, i8 %y) {
; CHECK-LABEL: @replace_false_op_eq_neg_and_leak2(
; CHECK-NEXT:    [[EQ0:%.*]] = icmp eq i8 [[X:%.*]], 0
; CHECK-NEXT:    [[NEG:%.*]] = sub i8 0, [[X]]
; CHECK-NEXT:    [[AND:%.*]] = and i8 [[NEG]], [[Y:%.*]]
; CHECK-NEXT:    [[SEL:%.*]] = select i1 [[EQ0]], i8 0, i8 [[AND]]
; CHECK-NEXT:    ret i8 [[SEL]]
;
  %eq0 = icmp eq i8 %x, 0
  %neg = sub i8 0, %x
  %and = and i8 %neg, %y
  %sel = select i1 %eq0, i8 0, i8 %and
  ret i8 %sel
}

; negative test - can't have extra source of potential poison

define i8 @replace_false_op_eq_add_mul_leak3(i8 %x, i8 %y) {
; CHECK-LABEL: @replace_false_op_eq_add_mul_leak3(
; CHECK-NEXT:    [[EQ0:%.*]] = icmp eq i8 [[X:%.*]], 0
; CHECK-NEXT:    [[ADD:%.*]] = add i8 [[X]], [[Y:%.*]]
; CHECK-NEXT:    [[MUL:%.*]] = mul i8 [[ADD]], [[X]]
; CHECK-NEXT:    [[SEL:%.*]] = select i1 [[EQ0]], i8 0, i8 [[MUL]]
; CHECK-NEXT:    ret i8 [[SEL]]
;
  %eq0 = icmp eq i8 %x, 0
  %add = add i8 %x, %y
  %mul = mul i8 %add, %x
  %sel = select i1 %eq0, i8 0, i8 %mul
  ret i8 %sel
}

; negative test - can't have extra source of potential poison

define i8 @replace_false_op_eq_shl_or_leak4(i8 %x, i8 %y) {
; CHECK-LABEL: @replace_false_op_eq_shl_or_leak4(
; CHECK-NEXT:    [[EQ0:%.*]] = icmp eq i8 [[X:%.*]], -1
; CHECK-NEXT:    [[SHL:%.*]] = shl i8 [[Y:%.*]], [[X]]
; CHECK-NEXT:    [[OR:%.*]] = or i8 [[X]], [[SHL]]
; CHECK-NEXT:    [[SEL:%.*]] = select i1 [[EQ0]], i8 -1, i8 [[OR]]
; CHECK-NEXT:    ret i8 [[SEL]]
;
  %eq0 = icmp eq i8 %x, -1
  %shl = shl i8 %y, %x
  %or = or i8 %x, %shl
  %sel = select i1 %eq0, i8 -1, i8 %or
  ret i8 %sel
}

; negative test - wrong cmp constant

define i8 @replace_false_op_eq42_neg_and(i8 %x) {
; CHECK-LABEL: @replace_false_op_eq42_neg_and(
; CHECK-NEXT:    [[EQ42:%.*]] = icmp eq i8 [[X:%.*]], 42
; CHECK-NEXT:    [[NEG:%.*]] = sub i8 0, [[X]]
; CHECK-NEXT:    [[AND:%.*]] = and i8 [[NEG]], [[X]]
; CHECK-NEXT:    [[SEL:%.*]] = select i1 [[EQ42]], i8 0, i8 [[AND]]
; CHECK-NEXT:    ret i8 [[SEL]]
;
  %eq42 = icmp eq i8 %x, 42
  %neg = sub i8 0, %x
  %and = and i8 %neg, %x
  %sel = select i1 %eq42, i8 0, i8 %and
  ret i8 %sel
}

define ptr @select_op_replacement_in_phi(ptr %head) {
; CHECK-LABEL: @select_op_replacement_in_phi(
; CHECK-NEXT:  entry:
; CHECK-NEXT:    br label [[LOOP:%.*]]
; CHECK:       loop:
; CHECK-NEXT:    [[CURRENT:%.*]] = phi ptr [ [[HEAD:%.*]], [[ENTRY:%.*]] ], [ [[NEXT:%.*]], [[LATCH:%.*]] ]
; CHECK-NEXT:    [[PREV:%.*]] = phi ptr [ null, [[ENTRY]] ], [ [[CURRENT]], [[LATCH]] ]
; CHECK-NEXT:    [[CURRENT_NULL:%.*]] = icmp eq ptr [[CURRENT]], null
; CHECK-NEXT:    [[SEL:%.*]] = select i1 [[CURRENT_NULL]], ptr [[PREV]], ptr null
; CHECK-NEXT:    br i1 [[CURRENT_NULL]], label [[EXIT:%.*]], label [[LATCH]]
; CHECK:       latch:
; CHECK-NEXT:    [[NEXT]] = load ptr, ptr [[CURRENT]], align 8
; CHECK-NEXT:    br label [[LOOP]]
; CHECK:       exit:
; CHECK-NEXT:    ret ptr [[SEL]]
;
entry:
  br label %loop

loop:
  %current = phi ptr [ %head, %entry ], [ %next, %latch ]
  %prev = phi ptr [ null, %entry ], [ %current, %latch ]
  %current.null = icmp eq ptr %current, null
  %sel = select i1 %current.null, ptr %prev, ptr null
  br i1 %current.null, label %exit, label %latch

latch:
  %next = load ptr, ptr %current
  br label %loop

exit:
  ret ptr %sel
}

define i8 @select_sub_cmp(i8 %0, i8 %1) {
; CHECK-LABEL: @select_sub_cmp(
; CHECK-NEXT:    [[TMP3:%.*]] = sub nsw i8 [[TMP1:%.*]], [[TMP0:%.*]]
; CHECK-NEXT:    ret i8 [[TMP3]]
;
  %3 = icmp eq i8 %1, %0
  %4 = sub nsw i8 %1, %0
  %5 = select i1 %3, i8 0, i8 %4
  ret i8 %5
}

define <2 x i8> @select_sub_cmp_vec(<2 x i8> %0, <2 x i8> %1) {
; CHECK-LABEL: @select_sub_cmp_vec(
; CHECK-NEXT:    [[TMP3:%.*]] = sub nsw <2 x i8> [[TMP1:%.*]], [[TMP0:%.*]]
; CHECK-NEXT:    ret <2 x i8> [[TMP3]]
;
  %3 = icmp eq <2 x i8> %1, %0
  %4 = sub nsw <2 x i8> %1, %0
  %5 = select <2 x i1> %3, <2 x i8> <i8 0, i8 0>, <2 x i8> %4
  ret <2 x i8> %5
}

define i8 @select_sub_cmp_swap(i8 %0, i8 %1) {
; CHECK-LABEL: @select_sub_cmp_swap(
; CHECK-NEXT:    [[TMP3:%.*]] = sub nsw i8 [[TMP0:%.*]], [[TMP1:%.*]]
; CHECK-NEXT:    ret i8 [[TMP3]]
;
  %3 = icmp eq i8 %1, %0
  %4 = sub nsw i8 %0, %1
  %5 = select i1 %3, i8 0, i8 %4
  ret i8 %5
}

define <2 x i8> @select_sub_cmp_vec_swap(<2 x i8> %0, <2 x i8> %1) {
; CHECK-LABEL: @select_sub_cmp_vec_swap(
; CHECK-NEXT:    [[TMP3:%.*]] = sub nsw <2 x i8> [[TMP0:%.*]], [[TMP1:%.*]]
; CHECK-NEXT:    ret <2 x i8> [[TMP3]]
;
  %3 = icmp eq <2 x i8> %1, %0
  %4 = sub nsw <2 x i8> %0, %1
  %5 = select <2 x i1> %3, <2 x i8> <i8 0, i8 0>, <2 x i8> %4
  ret <2 x i8> %5
}

; negative test
define i8 @select_sub_cmp_nonzero(i8 %0, i8 %1) {
; CHECK-LABEL: @select_sub_cmp_nonzero(
; CHECK-NEXT:    [[TMP3:%.*]] = icmp eq i8 [[TMP1:%.*]], [[TMP0:%.*]]
; CHECK-NEXT:    [[TMP4:%.*]] = sub nsw i8 [[TMP1]], [[TMP0]]
; CHECK-NEXT:    [[TMP5:%.*]] = select i1 [[TMP3]], i8 42, i8 [[TMP4]]
; CHECK-NEXT:    ret i8 [[TMP5]]
;
  %3 = icmp eq i8 %1, %0
  %4 = sub nsw i8 %1, %0
  %5 = select i1 %3, i8 42, i8 %4
  ret i8 %5
}

; X == Y ? 0 : X ^ Y --> X ^ Y, https://alive2.llvm.org/ce/z/cykffE
define i8 @select_xor_cmp(i8 %0, i8 %1) {
; CHECK-LABEL: @select_xor_cmp(
; CHECK-NEXT:    [[TMP3:%.*]] = xor i8 [[TMP1:%.*]], [[TMP0:%.*]]
; CHECK-NEXT:    ret i8 [[TMP3]]
;
  %3 = icmp eq i8 %1, %0
  %4 = xor i8 %1, %0
  %5 = select i1 %3, i8 0, i8 %4
  ret i8 %5
}

define <2 x i8> @select_xor_cmp_vec(<2 x i8> %0, <2 x i8> %1) {
; CHECK-LABEL: @select_xor_cmp_vec(
; CHECK-NEXT:    [[TMP3:%.*]] = xor <2 x i8> [[TMP1:%.*]], [[TMP0:%.*]]
; CHECK-NEXT:    ret <2 x i8> [[TMP3]]
;
  %3 = icmp eq <2 x i8> %1, %0
  %4 = xor <2 x i8> %1, %0
  %5 = select <2 x i1> %3, <2 x i8> <i8 0, i8 0>, <2 x i8> %4
  ret <2 x i8> %5
}

define i8 @select_xor_cmp_swap(i8 %0, i8 %1) {
; CHECK-LABEL: @select_xor_cmp_swap(
; CHECK-NEXT:    [[TMP3:%.*]] = xor i8 [[TMP0:%.*]], [[TMP1:%.*]]
; CHECK-NEXT:    ret i8 [[TMP3]]
;
  %3 = icmp eq i8 %1, %0
  %4 = xor i8 %0, %1
  %5 = select i1 %3, i8 0, i8 %4
  ret i8 %5
}

define <2 x i8> @select_xor_cmp_vec_swap(<2 x i8> %0, <2 x i8> %1) {
; CHECK-LABEL: @select_xor_cmp_vec_swap(
; CHECK-NEXT:    [[TMP3:%.*]] = xor <2 x i8> [[TMP0:%.*]], [[TMP1:%.*]]
; CHECK-NEXT:    ret <2 x i8> [[TMP3]]
;
  %3 = icmp eq <2 x i8> %1, %0
  %4 = xor <2 x i8> %0, %1
  %5 = select <2 x i1> %3, <2 x i8> <i8 0, i8 0>, <2 x i8> %4
  ret <2 x i8> %5
}

; Negative test: the xor operands are not %0 and %1
define i8 @select_xor_cmp_unmatched_operands(i8 %0, i8 %1, i8 %c) {
; CHECK-LABEL: @select_xor_cmp_unmatched_operands(
; CHECK-NEXT:    [[TMP3:%.*]] = icmp eq i8 [[TMP1:%.*]], [[TMP0:%.*]]
; CHECK-NEXT:    [[TMP4:%.*]] = xor i8 [[TMP1]], [[C:%.*]]
; CHECK-NEXT:    [[TMP5:%.*]] = select i1 [[TMP3]], i8 0, i8 [[TMP4]]
; CHECK-NEXT:    ret i8 [[TMP5]]
;
  %3 = icmp eq i8 %1, %0
  %4 = xor i8 %1, %c
  %5 = select i1 %3, i8 0, i8 %4
  ret i8 %5
}