xref: /llvm-project/llvm/test/Analysis/BasicAA/dag.ll (revision 303c308e452c703c3d47940383ded3b2d3eefd56)
1; RUN: opt < %s -aa-pipeline=basic-aa -passes=aa-eval -print-all-alias-modref-info 2>&1 | 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"
4
5; BasicAA's guard against use-def cycles shouldn't prevent it from
6; analyzing use-def dags.
7
8; CHECK: MustAlias:  i8* %base, i8* %phi
9; CHECK: MustAlias: i16* %base, i8* %base
10; CHECK: MustAlias: i16* %base, i8* %phi
11define i8 @foo(ptr %base, i1 %x, i1 %w) {
12entry:
13  load i8, ptr %base
14  br i1 %w, label %wa, label %wb
15wa:
16  load i8, ptr %base
17  br label %wc
18wb:
19  load i8, ptr %base
20  br label %wc
21wc:
22  %first = phi ptr [ %base, %wa ], [ %base, %wb ]
23  br i1 %x, label %xa, label %xb
24xa:
25  br label %xc
26xb:
27  br label %xc
28xc:
29  %phi = phi ptr [ %first, %xa ], [ %first, %xb ]
30
31  store i8 0, ptr %phi
32
33  store i16 -1, ptr %base
34
35  %loaded = load i8, ptr %phi
36  ret i8 %loaded
37}
38