1; RUN: opt -analyze --loop-accesses %s -enable-new-pm=0 | FileCheck %s
2; RUN: opt -passes=print-access-info %s -disable-output 2>&1 | FileCheck %s
3
4; This test verifies run-time boundary check of memory accesses.
5; The original loop:
6;   void fastCopy(const char* src, char* op) {
7;     int len = 32;
8;     while (len > 0) {
9;       *(reinterpret_cast<long long*>(op)) = *(reinterpret_cast<const long long*>(src));
10;       src += 8;
11;       op += 8;
12;       len -= 8;
13;     }
14;   }
15; Boundaries calculations before this patch:
16; (Low: %src High: (24 + %src))
17; and the actual distance between two pointers was 31,  (%op - %src = 31)
18; IsConflict = (24 > 31) = false -> execution is directed to the vectorized loop.
19; The loop was vectorized to 4, 32 byte memory access ( <4 x i64> ),
20; store a value at *%op touched memory under *%src.
21
22;CHECK: function 'fastCopy':
23;CHECK: (Low: %op High: (32 + %op))
24;CHECK: (Low: %src High: (32 + %src))
25
26define void @fastCopy(i8* nocapture readonly %src, i8* nocapture %op) {
27entry:
28  br label %while.body.preheader
29
30while.body.preheader:                             ; preds = %entry
31  br label %while.body
32
33while.body:                                       ; preds = %while.body.preheader, %while.body
34  %len.addr.07 = phi i32 [ %sub, %while.body ], [ 32, %while.body.preheader ]
35  %op.addr.06 = phi i8* [ %add.ptr1, %while.body ], [ %op, %while.body.preheader ]
36  %src.addr.05 = phi i8* [ %add.ptr, %while.body ], [ %src, %while.body.preheader ]
37  %0 = bitcast i8* %src.addr.05 to i64*
38  %1 = load i64, i64* %0, align 8
39  %2 = bitcast i8* %op.addr.06 to i64*
40  store i64 %1, i64* %2, align 8
41  %add.ptr = getelementptr inbounds i8, i8* %src.addr.05, i64 8
42  %add.ptr1 = getelementptr inbounds i8, i8* %op.addr.06, i64 8
43  %sub = add nsw i32 %len.addr.07, -8
44  %cmp = icmp sgt i32 %len.addr.07, 8
45  br i1 %cmp, label %while.body, label %while.end.loopexit
46
47while.end.loopexit:                               ; preds = %while.body
48  br label %while.end
49
50while.end:                                        ; preds = %while.end.loopexit, %entry
51  ret void
52}
53