File: tail-call.ll

package info (click to toggle)
llvm-toolchain-3.9 1%3A3.9.1-8
  • links: PTS, VCS
  • area: main
  • in suites: stretch
  • size: 441,060 kB
  • ctags: 428,777
  • sloc: cpp: 2,546,577; ansic: 538,318; asm: 119,677; objc: 103,316; python: 102,148; sh: 27,847; pascal: 5,626; ml: 5,510; perl: 5,293; lisp: 4,801; makefile: 2,177; xml: 686; cs: 362; php: 212; csh: 117
file content (32 lines) | stat: -rw-r--r-- 875 bytes parent folder | download | duplicates (5)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
; 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
}