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| ; RUN: llc -verify-machineinstrs -mtriple=arm64-apple-ios7.0 -o - %s | FileCheck %s
@var = global void()* zeroinitializer
declare void @bar()
define void @foo() {
; CHECK-LABEL: foo:
%func = load void()*, void()** @var
; Calling a function encourages @foo to use a callee-saved register,
; which makes it a natural choice for the tail call itself. But we don't
; want that: the final "br xN" has to use a temporary or argument
; register.
call void @bar()
tail call void %func()
; CHECK: br {{x([0-79]|1[0-8])}}
ret void
}
; No matter how tempting it is, LLVM should not use x30 since that'll be
; restored to its incoming value before the "br".
define void @test_x30_tail() {
; CHECK-LABEL: test_x30_tail:
; CHECK: mov [[DEST:x[0-9]+]], x30
; CHECK: br [[DEST]]
%addr = call i8* @llvm.returnaddress(i32 0)
%faddr = bitcast i8* %addr to void()*
tail call void %faddr()
ret void
}
declare i8* @llvm.returnaddress(i32)
|