File: arg-attr-propagation.ll

package info (click to toggle)
llvm-toolchain-9 1%3A9.0.1-16.1
  • links: PTS, VCS
  • area: main
  • in suites: bullseye
  • size: 882,388 kB
  • sloc: cpp: 4,167,636; ansic: 714,256; asm: 457,610; python: 155,927; objc: 65,094; sh: 42,856; lisp: 26,908; perl: 7,786; pascal: 7,722; makefile: 6,881; ml: 5,581; awk: 3,648; cs: 2,027; xml: 888; javascript: 381; ruby: 156
file content (50 lines) | stat: -rw-r--r-- 1,542 bytes parent folder | download | duplicates (6)
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
39
40
41
42
43
44
45
46
47
48
49
50
; RUN: opt -inline -S < %s | FileCheck %s

; The callee guarantees that the pointer argument is nonnull and dereferenceable.
; That information should transfer to the caller.

define i32 @callee(i32* dereferenceable(32) %t1) {
; CHECK-LABEL: @callee(i32* dereferenceable(32) %t1)
; CHECK-NEXT:    [[T2:%.*]] = load i32, i32* %t1
; CHECK-NEXT:    ret i32 [[T2]]
;
  %t2 = load i32, i32* %t1
  ret i32 %t2
}

; FIXME: All dereferenceability information is lost.
; The caller argument could be known nonnull and dereferenceable(32).

define i32 @caller1(i32* %t1) {
; CHECK-LABEL: @caller1(i32* %t1)
; CHECK-NEXT:    [[T2_I:%.*]] = load i32, i32* %t1
; CHECK-NEXT:    ret i32 [[T2_I]]
;
  %t2 = tail call i32 @callee(i32* dereferenceable(32) %t1)
  ret i32 %t2
}

; The caller argument is nonnull, but that can be explicit.
; The dereferenceable amount could be increased.

define i32 @caller2(i32* dereferenceable(31) %t1) {
; CHECK-LABEL: @caller2(i32* dereferenceable(31) %t1)
; CHECK-NEXT:    [[T2_I:%.*]] = load i32, i32* %t1
; CHECK-NEXT:    ret i32 [[T2_I]]
;
  %t2 = tail call i32 @callee(i32* dereferenceable(32) %t1)
  ret i32 %t2
}

; The caller argument is nonnull, but that can be explicit.
; Make sure that we don't propagate a smaller dereferenceable amount.

define i32 @caller3(i32* dereferenceable(33) %t1) {
; CHECK-LABEL: @caller3(i32* dereferenceable(33) %t1)
; CHECK-NEXT:    [[T2_I:%.*]] = load i32, i32* %t1
; CHECK-NEXT:    ret i32 [[T2_I]]
;
  %t2 = tail call i32 @callee(i32* dereferenceable(32) %t1)
  ret i32 %t2
}