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; RUN: opt -basicaa -loop-accesses -analyze < %s | FileCheck %s
; RUN: opt -passes='require<scalar-evolution>,require<aa>,loop(print-access-info)' -disable-output < %s 2>&1 | FileCheck %s
; In:
;
; store_ptr = A;
; load_ptr = &A[2];
; for (i = 0; i < n; i++)
; *store_ptr++ = *load_ptr++ *10; // A[i] = A[i+2] * 10
;
; make sure, we look through the PHI to conclude that store_ptr and load_ptr
; both have A as their underlying object. The dependence is safe for
; vectorization requiring no memchecks.
;
; Otherwise we would try to prove independence with a memcheck that is going
; to always fail.
target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-apple-macosx10.10.0"
; CHECK: Memory dependences are safe{{$}}
define void @f(i8* noalias %A, i64 %width) {
for.body.preheader:
%A_ahead = getelementptr inbounds i8, i8* %A, i64 2
br label %for.body
for.body:
%i = phi i64 [ %i.1, %for.body ], [ 0, %for.body.preheader ]
%load_ptr = phi i8* [ %load_ptr.1, %for.body ], [ %A_ahead, %for.body.preheader ]
%store_ptr = phi i8* [ %store_ptr.1, %for.body ], [ %A, %for.body.preheader ]
%loadA = load i8, i8* %load_ptr, align 1
%mul = mul i8 %loadA, 10
store i8 %mul, i8* %store_ptr, align 1
%load_ptr.1 = getelementptr inbounds i8, i8* %load_ptr, i64 1
%store_ptr.1 = getelementptr inbounds i8, i8* %store_ptr, i64 1
%i.1 = add nuw i64 %i, 1
%exitcond = icmp eq i64 %i.1, %width
br i1 %exitcond, label %for.end, label %for.body
for.end:
ret void
}
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