1; RUN: opt < %s  -loop-vectorize -force-vector-interleave=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; Make sure that the reverse iterators are calculated using 64bit arithmetic, not 32.
7;
8; int foo(int n, int *A) {
9;   int sum;
10;   for (int i=n; i > 0; i--)
11;     sum += A[i*2];
12;   return sum;
13; }
14;
15
16;CHECK-LABEL: @foo(
17;CHECK:  <i64 0, i64 -1, i64 -2, i64 -3>
18;CHECK: ret
19define i32 @foo(i32 %n, i32* nocapture %A) {
20  %1 = icmp sgt i32 %n, 0
21  br i1 %1, label %.lr.ph, label %._crit_edge
22
23.lr.ph:                                           ; preds = %0
24  %2 = sext i32 %n to i64
25  br label %3
26
27; <label>:3                                       ; preds = %.lr.ph, %3
28  %indvars.iv = phi i64 [ %2, %.lr.ph ], [ %indvars.iv.next, %3 ]
29  %sum.01 = phi i32 [ undef, %.lr.ph ], [ %9, %3 ]
30  %4 = trunc i64 %indvars.iv to i32
31  %5 = shl nsw i32 %4, 1
32  %6 = sext i32 %5 to i64
33  %7 = getelementptr inbounds i32, i32* %A, i64 %6
34  %8 = load i32, i32* %7, align 4
35  %9 = add nsw i32 %8, %sum.01
36  %indvars.iv.next = add i64 %indvars.iv, -1
37  %10 = trunc i64 %indvars.iv.next to i32
38  %11 = icmp sgt i32 %10, 0
39  br i1 %11, label %3, label %._crit_edge
40
41._crit_edge:                                      ; preds = %3, %0
42  %sum.0.lcssa = phi i32 [ undef, %0 ], [ %9, %3 ]
43  ret i32 %sum.0.lcssa
44}
45
46