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1; RUN: llc -verify-machineinstrs -mtriple=arm64-apple-ios7.0 -o - %s | FileCheck %s
2@var = global void()* zeroinitializer
3
4declare void @bar()
5
6define void @foo() {
7; CHECK-LABEL: foo:
8       %func = load void()*, void()** @var
9
10       ; Calling a function encourages @foo to use a callee-saved register,
11       ; which makes it a natural choice for the tail call itself. But we don't
12       ; want that: the final "br xN" has to use a temporary or argument
13       ; register.
14       call void @bar()
15
16       tail call void %func()
17; CHECK: br {{x([0-79]|1[0-8])}}
18       ret void
19}
20
21; No matter how tempting it is, LLVM should not use x30 since that'll be
22; restored to its incoming value before the "br".
23define void @test_x30_tail() {
24; CHECK-LABEL: test_x30_tail:
25; CHECK: mov [[DEST:x[0-9]+]], x30
26; CHECK: br [[DEST]]
27  %addr = call i8* @llvm.returnaddress(i32 0)
28  %faddr = bitcast i8* %addr to void()*
29  tail call void %faddr()
30  ret void
31}
32
33declare i8* @llvm.returnaddress(i32)
34