File: early-cse.ll

package info (click to toggle)
llvm-toolchain-13 1%3A13.0.1-6~deb11u1
  • links: PTS, VCS
  • area: main
  • in suites: bullseye
  • size: 1,418,812 kB
  • sloc: cpp: 5,290,827; ansic: 996,570; asm: 544,593; python: 188,212; objc: 72,027; lisp: 30,291; f90: 25,395; sh: 24,900; javascript: 9,780; pascal: 9,398; perl: 7,484; ml: 5,432; awk: 3,523; makefile: 2,892; xml: 953; cs: 573; fortran: 539
file content (89 lines) | stat: -rw-r--r-- 2,232 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
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
; RUN: opt -S -early-cse -earlycse-debug-hash < %s | FileCheck %s

; While it is normally okay to do memory optimizations over calls to
; @readonly_function and @readnone_function, we cannot do that if
; they're carrying unknown operand bundles since the presence of
; unknown operand bundles implies arbitrary memory effects.

declare void @readonly_function() readonly nounwind willreturn
declare void @readnone_function() readnone nounwind willreturn

define i32 @test0(i32* %x) {
; CHECK-LABEL: @test0(
 entry:
  store i32 100, i32* %x
; CHECK: store i32 100, i32* %x
  call void @readonly_function() [ "tag"() ]
; CHECK: call void @readonly_function()

  %v = load i32, i32* %x
; CHECK: %v = load i32, i32* %x
; CHECK: ret i32 %v
  ret i32 %v
}

define i32 @test1(i32* %x) {
; CHECK: @test1(
 entry:
  store i32 100, i32* %x
; CHECK: store i32 100, i32* %x
  call void @readonly_function() readonly [ "tag"() ]
; CHECK-NOT: call void @readonly_function
  %v = load i32, i32* %x
  ret i32 %v
; CHECK: ret i32 100
}

define i32 @test3(i32* %x) {
; CHECK-LABEL: @test3(
 entry:
  store i32 100, i32* %x
; CHECK: store i32 100, i32* %x
  call void @readonly_function()
; CHECK-NOT: call void @readonly_function
  %v = load i32, i32* %x
  ret i32 %v
; CHECK: ret i32 100
}

define void @test4(i32* %x) {
; CHECK-LABEL: @test4(
 entry:
  store i32 100, i32* %x
; CHECK: store i32 100, i32* %x
  call void @readnone_function() [ "tag"() ]
; CHECK: call void @readnone_function
  store i32 200, i32* %x
; CHECK: store i32 200, i32* %x
  ret void
}

define void @test5(i32* %x) {
; CHECK-LABEL: @test5(
 entry:
  store i32 100, i32* %x
; CHECK-NOT: store i32 100, i32* %x
; CHECK-NOT: call void @readnone_function
  call void @readnone_function() readnone [ "tag"() ]
  store i32 200, i32* %x
; CHECK: store i32 200, i32* %x
  ret void
}

define void @test6(i32* %x) {
; The "deopt" operand bundle does not make the call to
; @readonly_function read-write; and so the nounwind readonly call can
; be deleted.

; CHECK-LABEL: @test6(
 entry:

; CHECK-NEXT: entry:
; CHECK-NEXT:  store i32 200, i32* %x
; CHECK-NEXT:  ret void

  store i32 100, i32* %x
  call void @readonly_function() [ "deopt"() ]
  store i32 200, i32* %x
  ret void
}