no-hoist-prof.ll
3.42 KB
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
; RUN: opt -enable-new-pm=1 -sample-profile -licm -S -sample-profile-file='%S/Inputs/no-hoist-prof.prof' < %s | FileCheck %s --check-prefix=CHECK-BFI-LICM
; RUN: opt -passes=licm -S < %s | FileCheck %s --check-prefix=CHECK-LICM
; Original source code:
;
; int bar(int);
; int foo(int iter, int explode) {
; int base = bar(explode);
; for (int i = 0; i != iter; ++i)
; if (i == explode)
; iter = (base * base) + bar(iter);
; return iter;
; }
; We need debug information in this .ll in order to leverage the pgo file, so:
; .ll generated by running `clang++ -O3 -g -S -emit-llvm`, then:
; - move hoisted mul back into cold section
; - give labels names
; - reindex variables
; - remove metadata calls, attributes, module header
; - remove unnecessary metadata
; CHECK-LICM: .l.check.preheader:{{.*}}
; CHECK-LICM-NEXT: {{.*}} = mul {{.*}}
; CHECK-LICM-NEXT: br{{.*}}
; CHECK-BFI-LICM: .l.cold:{{.*}}
; CHECK-BFI-LICM-NEXT: {{.*}} = mul {{.*}}
define dso_local i32 @_Z3fooii(i32, i32) local_unnamed_addr #0 !dbg !7 {
%3 = tail call i32 @_Z3bari(i32 %1), !dbg !19
%4 = icmp eq i32 %0, 0, !dbg !22
br i1 %4, label %.l.ret, label %.l.check.preheader, !dbg !24
.l.check.preheader:
br label %.l.check, !dbg !24
.l.ret:
%5 = phi i32 [ 0, %2 ], [ %12, %.l.iterate ]
ret i32 %5, !dbg !25
.l.check:
%6 = phi i32 [ 0, %.l.check.preheader ], [ %13, %.l.iterate ]
%7 = phi i32 [ %0, %.l.check.preheader ], [ %12, %.l.iterate ]
%8 = icmp eq i32 %6, %1, !dbg !26
br i1 %8, label %.l.cold, label %.l.iterate, !dbg !28
.l.cold:
%9 = mul nsw i32 %3, %3
%10 = tail call i32 @_Z3bari(i32 %7), !dbg !29
%11 = add nsw i32 %10, %9, !dbg !30
br label %.l.iterate, !dbg !31
.l.iterate:
%12 = phi i32 [ %11, %.l.cold ], [ %7, %.l.check ]
%13 = add nuw nsw i32 %6, 1, !dbg !32
%14 = icmp eq i32 %13, %12, !dbg !22
br i1 %14, label %.l.ret, label %.l.check, !dbg !24, !llvm.loop !33
}
attributes #0 = { "use-sample-profile" }
declare dso_local i32 @_Z3bari(i32) local_unnamed_addr #1
!llvm.module.flags = !{!4}
!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !1, producer: "clang version 8.0.20181009 ", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, nameTableKind: None)
!1 = !DIFile(filename: "foo.cpp", directory: "/tmp/gather_pgo")
!4 = !{i32 2, !"Debug Info Version", i32 3}
!7 = distinct !DISubprogram(name: "foo", linkageName: "_Z3fooii", scope: !1, file: !1, line: 2, type: !8, isLocal: false, isDefinition: true, scopeLine: 2, flags: DIFlagPrototyped, isOptimized: true, unit: !0)
!8 = !DISubroutineType(types: !9)
!9 = !{!10, !10, !10}
!10 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
!16 = distinct !DILexicalBlock(scope: !7, file: !1, line: 4, column: 3)
!19 = !DILocation(line: 3, column: 14, scope: !7)
!22 = !DILocation(line: 4, column: 21, scope: !23)
!23 = distinct !DILexicalBlock(scope: !16, file: !1, line: 4, column: 3)
!24 = !DILocation(line: 4, column: 3, scope: !16)
!25 = !DILocation(line: 7, column: 3, scope: !7)
!26 = !DILocation(line: 5, column: 11, scope: !27)
!27 = distinct !DILexicalBlock(scope: !23, file: !1, line: 5, column: 9)
!28 = !DILocation(line: 5, column: 9, scope: !23)
!29 = !DILocation(line: 6, column: 30, scope: !27)
!30 = !DILocation(line: 6, column: 28, scope: !27)
!31 = !DILocation(line: 6, column: 7, scope: !27)
!32 = !DILocation(line: 4, column: 30, scope: !23)
!33 = distinct !{!33, !24, !34}
!34 = !DILocation(line: 6, column: 38, scope: !16)