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1; RUN: opt -gvn-hoist -newgvn -gvn-hoist  -S < %s | FileCheck %s
2; Test to demonstrate that newgvn creates opportunities for
3; more gvn-hoist when sibling branches contain identical expressions.
4
5target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
6target triple = "x86_64-unknown-linux-gnu"
7
8; Check that all "or" expressions are hoisted.
9; CHECK-LABEL: @encode
10; CHECK: or i32
11; CHECK-NOT: or i32
12
13define i8* @encode(i8* %p, i32 %v) {
14entry:
15  %p.addr = alloca i8*, align 8
16  %v.addr = alloca i32, align 4
17  store i8* %p, i8** %p.addr, align 8
18  store i32 %v, i32* %v.addr, align 4
19  %0 = load i32, i32* %v.addr, align 4
20  %cmp = icmp ult i32 %0, 23
21  br i1 %cmp, label %if.then, label %if.else
22
23if.then:                                          ; preds = %entry
24  %1 = load i32, i32* %v.addr, align 4
25  %or = or i32 %1, 128
26  %conv = trunc i32 %or to i8
27  %2 = load i8*, i8** %p.addr, align 8
28  %incdec.ptr = getelementptr inbounds i8, i8* %2, i32 1
29  store i8* %incdec.ptr, i8** %p.addr, align 8
30  store i8 %conv, i8* %2, align 1
31  br label %if.end15
32
33if.else:                                          ; preds = %entry
34  %3 = load i32, i32* %v.addr, align 4
35  %cmp1 = icmp ult i32 %3, 42
36  br i1 %cmp1, label %if.then3, label %if.else9
37
38if.then3:                                         ; preds = %if.else
39  %4 = load i32, i32* %v.addr, align 4
40  %or4 = or i32 %4, 128
41  %conv5 = trunc i32 %or4 to i8
42  %5 = load i8*, i8** %p.addr, align 8
43  %incdec.ptr6 = getelementptr inbounds i8, i8* %5, i32 1
44  store i8* %incdec.ptr6, i8** %p.addr, align 8
45  store i8 %conv5, i8* %5, align 1
46  %6 = load i32, i32* %v.addr, align 4
47  %conv7 = trunc i32 %6 to i8
48  %7 = load i8*, i8** %p.addr, align 8
49  %incdec.ptr8 = getelementptr inbounds i8, i8* %7, i32 1
50  store i8* %incdec.ptr8, i8** %p.addr, align 8
51  store i8 %conv7, i8* %7, align 1
52  br label %if.end
53
54if.else9:                                         ; preds = %if.else
55  %8 = load i32, i32* %v.addr, align 4
56  %or10 = or i32 %8, 128
57  %conv11 = trunc i32 %or10 to i8
58  %9 = load i8*, i8** %p.addr, align 8
59  %incdec.ptr12 = getelementptr inbounds i8, i8* %9, i32 1
60  store i8* %incdec.ptr12, i8** %p.addr, align 8
61  store i8 %conv11, i8* %9, align 1
62  %10 = load i32, i32* %v.addr, align 4
63  %shr = lshr i32 %10, 7
64  %conv13 = trunc i32 %shr to i8
65  %11 = load i8*, i8** %p.addr, align 8
66  %incdec.ptr14 = getelementptr inbounds i8, i8* %11, i32 1
67  store i8* %incdec.ptr14, i8** %p.addr, align 8
68  store i8 %conv13, i8* %11, align 1
69  br label %if.end
70
71if.end:                                           ; preds = %if.else9, %if.then3
72  br label %if.end15
73
74if.end15:                                         ; preds = %if.end, %if.then
75  %12 = load i8*, i8** %p.addr, align 8
76  ret i8* %12
77}
78