| Arnold Schwaighofer | e3ac099 | 2014-01-16 04:53:18 +0000 | [diff] [blame^] | 1 | ; RUN: opt -S -basicaa -dse < %s | FileCheck %s |
| 2 | |
| 3 | target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" |
| 4 | target triple = "x86_64-unknown-linux-gnu" |
| 5 | |
| 6 | ; We incorrectly returned noalias in the example below for "ptr.64" and |
| 7 | ; "either_ptr.64". |
| 8 | ; PR18460 |
| 9 | |
| 10 | %nested = type { %nested.i64 } |
| 11 | %nested.i64 = type { i64 } |
| 12 | |
| 13 | define i64 @testcase(%nested * noalias %p1, %nested * noalias %p2, |
| 14 | i32 %a, i32 %b) { |
| 15 | %ptr = getelementptr inbounds %nested* %p1, i64 -1, i32 0 |
| 16 | %ptr.64 = getelementptr inbounds %nested.i64* %ptr, i64 0, i32 0 |
| 17 | %ptr2= getelementptr inbounds %nested* %p2, i64 0, i32 0 |
| 18 | %cmp = icmp ult i32 %a, %b |
| 19 | %either_ptr = select i1 %cmp, %nested.i64* %ptr2, %nested.i64* %ptr |
| 20 | %either_ptr.64 = getelementptr inbounds %nested.i64* %either_ptr, i64 0, i32 0 |
| 21 | |
| 22 | ; Because either_ptr.64 and ptr.64 can alias (we used to return noalias) |
| 23 | ; elimination of the first store is not valid. |
| 24 | |
| 25 | ; CHECK: store i64 2 |
| 26 | ; CHECK: load |
| 27 | ; CHECK; store i64 1 |
| 28 | |
| 29 | store i64 2, i64* %ptr.64, align 8 |
| 30 | %r = load i64* %either_ptr.64, align 8 |
| 31 | store i64 1, i64* %ptr.64, align 8 |
| 32 | ret i64 %r |
| 33 | } |