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| ; RUN: opt -S -basicaa -dse < %s | FileCheck %s
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"
; We incorrectly returned noalias in the example below for "ptr.64" and
; "either_ptr.64".
; PR18460
%nested = type { %nested.i64 }
%nested.i64 = type { i64 }
define i64 @testcase(%nested * noalias %p1, %nested * noalias %p2,
i32 %a, i32 %b) {
%ptr = getelementptr inbounds %nested, %nested* %p1, i64 -1, i32 0
%ptr.64 = getelementptr inbounds %nested.i64, %nested.i64* %ptr, i64 0, i32 0
%ptr2= getelementptr inbounds %nested, %nested* %p2, i64 0, i32 0
%cmp = icmp ult i32 %a, %b
%either_ptr = select i1 %cmp, %nested.i64* %ptr2, %nested.i64* %ptr
%either_ptr.64 = getelementptr inbounds %nested.i64, %nested.i64* %either_ptr, i64 0, i32 0
; Because either_ptr.64 and ptr.64 can alias (we used to return noalias)
; elimination of the first store is not valid.
; CHECK: store i64 2
; CHECK: load
; CHECK: store i64 1
store i64 2, i64* %ptr.64, align 8
%r = load i64, i64* %either_ptr.64, align 8
store i64 1, i64* %ptr.64, align 8
ret i64 %r
}
|