File: variadic_safety.ll

package info (click to toggle)
llvm-toolchain-14 1%3A14.0.6-12
  • links: PTS, VCS
  • area: main
  • in suites: bookworm
  • size: 1,496,180 kB
  • sloc: cpp: 5,593,972; ansic: 986,872; asm: 585,869; python: 184,223; objc: 72,530; lisp: 31,119; f90: 27,793; javascript: 9,780; pascal: 9,762; sh: 9,482; perl: 7,468; ml: 5,432; awk: 3,523; makefile: 2,538; xml: 953; cs: 573; fortran: 567
file content (38 lines) | stat: -rw-r--r-- 1,280 bytes parent folder | download | duplicates (3)
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
33
34
35
36
37
38
; RUN: opt < %s -passes=deadargelim -S | FileCheck %s

declare void @llvm.va_start(i8*)

define internal i32 @va_func(i32 %a, i32 %b, ...) {
  %valist = alloca i8
  call void @llvm.va_start(i8* %valist)

  ret i32 %b
}

; Function derived from AArch64 ABI, where 8 integer arguments go in
; registers but the 9th goes on the stack. We really don't want to put
; just 7 args in registers and then start on the stack since any
; va_arg implementation already present in va_func won't be expecting
; it.
define i32 @call_va(i32 %in) {
  %stacked = alloca i32
  store i32 42, i32* %stacked
  %res = call i32(i32, i32, ...) @va_func(i32 %in, i32 %in, [6 x i32] undef, i32* byval(i32) %stacked)
  ret i32 %res
; CHECK: call i32 (i32, i32, ...) @va_func(i32 undef, i32 %in, [6 x i32] undef, i32* byval(i32) %stacked)
}

define internal i32 @va_deadret_func(i32 %a, i32 %b, ...) {
  %valist = alloca i8
  call void @llvm.va_start(i8* %valist)

  ret i32 %a
}

define void @call_deadret(i32 %in) {
  %stacked = alloca i32
  store i32 42, i32* %stacked
  call i32 (i32, i32, ...) @va_deadret_func(i32 undef, i32 %in, [6 x i32] undef, i32* byval(i32) %stacked)
  ret void
; CHECK: call void (i32, i32, ...) @va_deadret_func(i32 undef, i32 undef, [6 x i32] undef, i32* byval(i32) %stacked)
}