1; RUN: opt < %s -loop-vectorize -force-vector-unroll=2 -force-vector-width=4 -S | FileCheck %s
2
3target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"
4
5; Make sure consecutive vector generates correct negative indices.
6; PR15882
7
8; CHECK-LABEL: @reverse_induction_i64(
9; CHECK: add <4 x i64> %[[SPLAT:.*]], <i64 0, i64 -1, i64 -2, i64 -3>
10; CHECK: add <4 x i64> %[[SPLAT]], <i64 -4, i64 -5, i64 -6, i64 -7>
11
12define i32 @reverse_induction_i64(i64 %startval, i32 * %ptr) {
13entry:
14  br label %for.body
15
16for.body:
17  %add.i7 = phi i64 [ %startval, %entry ], [ %add.i, %for.body ]
18  %i.06 = phi i32 [ 0, %entry ], [ %inc4, %for.body ]
19  %redux5 = phi i32 [ 0, %entry ], [ %inc.redux, %for.body ]
20  %add.i = add i64 %add.i7, -1
21  %kind_.i = getelementptr inbounds i32* %ptr, i64 %add.i
22  %tmp.i1 = load i32* %kind_.i, align 4
23  %inc.redux = add i32 %tmp.i1, %redux5
24  %inc4 = add i32 %i.06, 1
25  %exitcond = icmp ne i32 %inc4, 1024
26  br i1 %exitcond, label %for.body, label %loopend
27
28loopend:
29  ret i32 %inc.redux
30}
31
32; CHECK-LABEL: @reverse_induction_i128(
33; CHECK: add <4 x i128> %[[SPLAT:.*]], <i128 0, i128 -1, i128 -2, i128 -3>
34; CHECK: add <4 x i128> %[[SPLAT]], <i128 -4, i128 -5, i128 -6, i128 -7>
35define i32 @reverse_induction_i128(i128 %startval, i32 * %ptr) {
36entry:
37  br label %for.body
38
39for.body:
40  %add.i7 = phi i128 [ %startval, %entry ], [ %add.i, %for.body ]
41  %i.06 = phi i32 [ 0, %entry ], [ %inc4, %for.body ]
42  %redux5 = phi i32 [ 0, %entry ], [ %inc.redux, %for.body ]
43  %add.i = add i128 %add.i7, -1
44  %kind_.i = getelementptr inbounds i32* %ptr, i128 %add.i
45  %tmp.i1 = load i32* %kind_.i, align 4
46  %inc.redux = add i32 %tmp.i1, %redux5
47  %inc4 = add i32 %i.06, 1
48  %exitcond = icmp ne i32 %inc4, 1024
49  br i1 %exitcond, label %for.body, label %loopend
50
51loopend:
52  ret i32 %inc.redux
53}
54
55; CHECK-LABEL: @reverse_induction_i16(
56; CHECK: add <4 x i16> %[[SPLAT:.*]], <i16 0, i16 -1, i16 -2, i16 -3>
57; CHECK: add <4 x i16> %[[SPLAT]], <i16 -4, i16 -5, i16 -6, i16 -7>
58
59define i32 @reverse_induction_i16(i16 %startval, i32 * %ptr) {
60entry:
61  br label %for.body
62
63for.body:
64  %add.i7 = phi i16 [ %startval, %entry ], [ %add.i, %for.body ]
65  %i.06 = phi i32 [ 0, %entry ], [ %inc4, %for.body ]
66  %redux5 = phi i32 [ 0, %entry ], [ %inc.redux, %for.body ]
67  %add.i = add i16 %add.i7, -1
68  %kind_.i = getelementptr inbounds i32* %ptr, i16 %add.i
69  %tmp.i1 = load i32* %kind_.i, align 4
70  %inc.redux = add i32 %tmp.i1, %redux5
71  %inc4 = add i32 %i.06, 1
72  %exitcond = icmp ne i32 %inc4, 1024
73  br i1 %exitcond, label %for.body, label %loopend
74
75loopend:
76  ret i32 %inc.redux
77}
78
79
80@a = common global [1024 x i32] zeroinitializer, align 16
81
82; We incorrectly transformed this loop into an empty one because we left the
83; induction variable in i8 type and truncated the exit value 1024 to 0.
84; int a[1024];
85;
86; void fail() {
87;   int reverse_induction = 1023;
88;   unsigned char forward_induction = 0;
89;   while ((reverse_induction) >= 0) {
90;     forward_induction++;
91;     a[reverse_induction] = forward_induction;
92;     --reverse_induction;
93;   }
94; }
95
96; CHECK-LABEL: @reverse_forward_induction_i64_i8(
97; CHECK: vector.body
98; CHECK: %index = phi i64 [ 0, %vector.ph ], [ %index.next, %vector.body ]
99; CHECK: %normalized.idx = sub i64 %index, 0
100; CHECK: %reverse.idx = sub i64 1023, %normalized.idx
101; CHECK: trunc i64 %index to i8
102
103define void @reverse_forward_induction_i64_i8() {
104entry:
105  br label %while.body
106
107while.body:
108  %indvars.iv = phi i64 [ 1023, %entry ], [ %indvars.iv.next, %while.body ]
109  %forward_induction.05 = phi i8 [ 0, %entry ], [ %inc, %while.body ]
110  %inc = add i8 %forward_induction.05, 1
111  %conv = zext i8 %inc to i32
112  %arrayidx = getelementptr inbounds [1024 x i32]* @a, i64 0, i64 %indvars.iv
113  store i32 %conv, i32* %arrayidx, align 4
114  %indvars.iv.next = add i64 %indvars.iv, -1
115  %0 = trunc i64 %indvars.iv to i32
116  %cmp = icmp sgt i32 %0, 0
117  br i1 %cmp, label %while.body, label %while.end
118
119while.end:
120  ret void
121}
122
123; CHECK-LABEL: @reverse_forward_induction_i64_i8_signed(
124; CHECK: vector.body:
125; CHECK:  %index = phi i64 [ 129, %vector.ph ], [ %index.next, %vector.body ]
126; CHECK:  %normalized.idx = sub i64 %index, 129
127; CHECK:  %reverse.idx = sub i64 1023, %normalized.idx
128; CHECK:  trunc i64 %index to i8
129
130define void @reverse_forward_induction_i64_i8_signed() {
131entry:
132  br label %while.body
133
134while.body:
135  %indvars.iv = phi i64 [ 1023, %entry ], [ %indvars.iv.next, %while.body ]
136  %forward_induction.05 = phi i8 [ -127, %entry ], [ %inc, %while.body ]
137  %inc = add i8 %forward_induction.05, 1
138  %conv = sext i8 %inc to i32
139  %arrayidx = getelementptr inbounds [1024 x i32]* @a, i64 0, i64 %indvars.iv
140  store i32 %conv, i32* %arrayidx, align 4
141  %indvars.iv.next = add i64 %indvars.iv, -1
142  %0 = trunc i64 %indvars.iv to i32
143  %cmp = icmp sgt i32 %0, 0
144  br i1 %cmp, label %while.body, label %while.end
145
146while.end:
147  ret void
148}
149