1; RUN: opt -S -loop-vectorize -force-vector-unroll=1 -force-vector-width=4 -dce -instcombine < %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"
4target triple = "x86_64-apple-macosx10.8.0"
5
6@uf = common global [100 x i32] zeroinitializer, align 16
7@xi = common global [100 x i32] zeroinitializer, align 16
8@q = common global [100 x i32] zeroinitializer, align 16
9
10; PR16455
11
12
13; Due to a bug in the way we handled reverse induction stores we would generate
14; a shuffle too many.
15
16define void @t()  {
17entry:
18  br label %for.body
19
20; CHECK-LABEL: @t(
21; CHECK: vector.body:
22; CHECK: load <4 x i32>
23; CHECK: [[VAR1:%[a-zA-Z0-9]+]] = shufflevector
24; CHECK: load <4 x i32>
25; CHECK: [[VAR2:%[a-zA-Z0-9]+]] = shufflevector
26; CHECK: [[VAR3:%[a-zA-Z0-9]+]] = add nsw <4 x i32> [[VAR2]], [[VAR1]]
27; CHECK: [[VAR4:%[a-zA-Z0-9]+]] = shufflevector <4 x i32> [[VAR3]]
28; CHECK: store <4 x i32> [[VAR4]]
29; CHECK: load <4 x i32>
30; CHECK: [[VAR5:%[a-zA-Z0-9]+]] = shufflevector
31; CHECK-NOT: add nsw <4 x i32> [[VAR4]], [[VAR5]]
32; CHECK-NOT: add nsw <4 x i32> [[VAR5]], [[VAR4]]
33; CHECK: add nsw <4 x i32> [[VAR3]], [[VAR5]]
34
35for.body:
36  %indvars.iv = phi i64 [ 93, %entry ], [ %indvars.iv.next, %for.body ]
37  %0 = add i64 %indvars.iv, 1
38  %arrayidx = getelementptr inbounds [100 x i32]* @uf, i64 0, i64 %0
39  %arrayidx3 = getelementptr inbounds [100 x i32]* @xi, i64 0, i64 %0
40  %1 = load i32* %arrayidx3, align 4
41  %2 = load i32* %arrayidx, align 4
42  %add4 = add nsw i32 %2, %1
43  store i32 %add4, i32* %arrayidx, align 4
44  %arrayidx7 = getelementptr inbounds [100 x i32]* @q, i64 0, i64 %0
45  %3 = load i32* %arrayidx7, align 4
46  %add8 = add nsw i32 %add4, %3
47  store i32 %add8, i32* %arrayidx, align 4
48  %indvars.iv.next = add i64 %indvars.iv, -1
49  %4 = trunc i64 %indvars.iv.next to i32
50  %cmp = icmp ugt i32 %4, 2
51  br i1 %cmp, label %for.body, label %for.end
52
53for.end:
54  ret void
55}
56