File: tail-call.ll

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llvm-toolchain-3.7 1%3A3.7.1-5
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; RUN: llc -mtriple armv7 -target-abi apcs -O0 -o - < %s \
; RUN:   | FileCheck %s -check-prefix CHECK-TAIL
; RUN: llc -mtriple armv7 -target-abi apcs -O0 -disable-tail-calls -o - < %s \
; RUN:   | FileCheck %s -check-prefix CHECK-NO-TAIL

declare i32 @callee(i32 %i)
declare extern_weak fastcc void @callee_weak()

define i32 @caller(i32 %i) {
entry:
  %r = tail call i32 @callee(i32 %i)
  ret i32 %r
}

; CHECK-TAIL-LABEL: caller
; CHECK-TAIL: b callee

; CHECK-NO-TAIL-LABEL: caller
; CHECK-NO-TAIL: push {lr}
; CHECK-NO-TAIL: bl callee
; CHECK-NO-TAIL: pop {lr}
; CHECK-NO-TAIL: bx lr


; Weakly-referenced extern functions cannot be tail-called, as AAELF does
; not define the behaviour of branch instructions to undefined weak symbols.
define fastcc void @caller_weak() {
; CHECK-LABEL: caller_weak:
; CHECK: bl callee_weak
  tail call void @callee_weak()
  ret void
}