File: jump-table.ll

package info (click to toggle)
llvm-toolchain-19 1%3A19.1.7-3
  • links: PTS, VCS
  • area: main
  • in suites: forky, sid, trixie
  • size: 1,998,520 kB
  • sloc: cpp: 6,951,680; ansic: 1,486,157; asm: 913,598; python: 232,024; f90: 80,126; objc: 75,281; lisp: 37,276; pascal: 16,990; sh: 10,009; ml: 5,058; perl: 4,724; awk: 3,523; makefile: 3,167; javascript: 2,504; xml: 892; fortran: 664; cs: 573
file content (262 lines) | stat: -rw-r--r-- 12,347 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
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
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
; REQUIRES: arm-registered-target
; REQUIRES: aarch64-registered-target
; REQUIRES: x86-registered-target
; RUN: llc -mtriple=i686-windows < %s | FileCheck %s --check-prefixes=CHECK,I686,NOTA32
; RUN: llc -mtriple=x86_64-windows < %s | FileCheck %s --check-prefixes=CHECK,X64,NOTA32
; RUN: llc -mtriple=aarch64-windows -aarch64-min-jump-table-entries=4 < %s | FileCheck %s --check-prefixes=CHECK,A64,NOTA32
; RUN: llc -mtriple=thumbv7a-windows < %s | FileCheck %s --check-prefixes=CHECK,A32
; RUN: llc -mtriple=x86_64-windows -filetype=obj < %s | llvm-readobj - --codeview | FileCheck %s --check-prefixes=CV

; Generated by clang++ -S -c -std=c++11 -emit-llvm -g from the following C++11 source:
; extern "C" void f1();
; extern "C" void f2();
; extern "C" void f3();
; extern "C" void f4();
; extern "C" void f5();
; extern "C" void func(int i){
;     switch (i) {
;         case 0: f1(); break;
;         case 1: f2(); break;
;         case 2: f3(); break;
;         case 3: f4(); break;
;     }
;     switch (i) {
;         case 1: f2(); break;
;         case 2: f3(); break;
;         case 3: f4(); break;
;         case 4: f5(); break;
;         case 5: f1(); break;
;     }
; }

; i686 entries are absolute addresses (Base = 0, SwitchType = Pointer).
; x86_64 entries are fixed-size and relative to the jump table (Base = Table,
;   SwitchType = Int32).
; aarch64 entries are variable-sized and relative to the first entry's BB if
;   compressed (Base = Branch+0x4, SwitchType = UInt8ShiftLeft/UInt16ShiftLeft)
;   otherwise relative to the ADR instruction (Base = Branch-0xc, SwitchType =
;   Int32).
; thumbv7a entries are either absolute addresses (Base = 0, SwitchType =
;   Pointer) OR variable-sized and relative to *after* the branch instruction
;   (Base = Branch+0x4, SwitchType = UInt8ShiftLeft/UInt16ShiftLeft/UInt32) but
;   there appears to be a bug where the offsets are always 0.

; Verify branch labels match what's in the CodeView
; X64:            .Ltmp1:
; X64-NEXT:       jmpq    *%{{.*}}
; X64:            .Ltmp4:
; X64-NEXT:       jmpq    *%{{.*}}
; A32:            .LCPI0_0:
; A32-NEXT        add     pc, r{{.*}}
; NOTE: thumbv7a places the jump tables just after the branch, so verify the other branch below
; A64:            .Ltmp1:
; A64-NEXT:       br      x{{.*}}
; A64:            .Ltmp4:
; A64-NEXT:       br      x{{.*}}

; Verify jump table have the same entry size, base offset and shift as what's in the CodeView
; CHECK:          {{\.?}}LJTI0_0:
; I686-NEXT:      .long   LBB0_[[#]]
; X64-NEXT:       .long   .LBB0_[[#]]-.LJTI0_0
; A32-NEXT:       .byte   (($MBB0_[[#]])-(.LCPI0_0+4))/2
; A64-NEXT:       .byte   (.LBB0_[[FIRSTBLOCK:[0-9]+]]-.LBB0_[[FIRSTBLOCK]])>>2
; NOTE: thumbv7a places the jump tables just after the branch, so check for the other branch now
; A32:            .LCPI0_1:
; A32-NEXT        add     pc, r{{.*}}
; CHECK:          {{\.?}}LJTI0_1:
; I686-NEXT:      .long   LBB0_[[#]]
; X64-NEXT:       .long   .LBB0_[[#]]-.LJTI0_1
; A32-NEXT:       .byte   (($MBB0_[[#]])-(.LCPI0_1+4))/2
; A64-NEXT:       .byte   (.LBB0_[[SECONDBLOCK:[0-9]+]]-.LBB0_[[SECONDBLOCK]])>>2

; Verify CodeView
; CHECK:          [[INT16:\.short|\.hword]]	4441        [[COMMENT:#|//|@]] Record kind: S_ARMSWITCHTABLE
; I686-NEXT:      .long 0                               [[COMMENT]] Base offset
; I686-NEXT:      .short 0                              [[COMMENT]] Base section index
; X64-NEXT:       .secrel32	.LJTI0_0                    [[COMMENT]] Base offset
; X64-NEXT:       .secidx	.LJTI0_0                      [[COMMENT]] Base section index
; A32-NEXT:       .secrel32	.LCPI0_0+4                  [[COMMENT]] Base offset
; A32-NEXT:       .secidx	.LCPI0_0                      [[COMMENT]] Base section index
; A64-NEXT:       .secrel32	.LBB0_[[FIRSTBLOCK]]        [[COMMENT]] Base offset
; A64-NEXT:       .secidx	.LBB0_[[FIRSTBLOCK]]          [[COMMENT]] Base section index
; I686-NEXT:      .short	6                             [[COMMENT]] Switch type
; X64-NEXT:       .short	4                             [[COMMENT]] Switch type
; A32-NEXT:       .short	7                             [[COMMENT]] Switch type
; A64-NEXT:       .hword	7                             [[COMMENT]] Switch type
; NOTA32-NEXT:    .secrel32	{{\.?}}Ltmp1                [[COMMENT]] Branch offset
; A32-NEXT:       .secrel32	.LCPI0_0                    [[COMMENT]] Branch offset
; CHECK-NEXT:     .secrel32	{{\.?}}LJTI0_0              [[COMMENT]] Table offset
; NOTA32-NEXT:    .secidx	{{\.?}}Ltmp1                  [[COMMENT]] Branch section index
; A32-NEXT:       .secidx	.LCPI0_0                      [[COMMENT]] Branch section index
; CHECK-NEXT:     .secidx	{{\.?}}LJTI0_0                [[COMMENT]] Table section index
; CHECK-NEXT:     [[INT32:\.long|\.word]]	4             [[COMMENT]] Entries count
; CHECK:          [[INT16]]	4441                        [[COMMENT]] Record kind: S_ARMSWITCHTABLE
; I686-NEXT:      .long 0                               [[COMMENT]] Base offset
; I686-NEXT:      .short 0                              [[COMMENT]] Base section index
; X64-NEXT:       .secrel32	.LJTI0_1                    [[COMMENT]] Base offset
; X64-NEXT:       .secidx	.LJTI0_1                      [[COMMENT]] Base section index
; A32-NEXT:       .secrel32	.LCPI0_1+4                  [[COMMENT]] Base offset
; A32-NEXT:       .secidx	.LCPI0_1                      [[COMMENT]] Base section index
; A64-NEXT:       .secrel32	.LBB0_[[SECONDBLOCK]]       [[COMMENT]] Base offset
; A64-NEXT:       .secidx	.LBB0_[[SECONDBLOCK]]         [[COMMENT]] Base section index
; I686-NEXT:      .short	6                             [[COMMENT]] Switch type
; X64-NEXT:       .short	4                             [[COMMENT]] Switch type
; A32-NEXT:       .short	7                             [[COMMENT]] Switch type
; A64-NEXT:       .hword	7                             [[COMMENT]] Switch type
; NOTA32-NEXT:    .secrel32	{{\.?}}Ltmp4                [[COMMENT]] Branch offset
; A32-NEXT:       .secrel32	.LCPI0_1                    [[COMMENT]] Branch offset
; CHECK-NEXT:     .secrel32	{{\.?}}LJTI0_1              [[COMMENT]] Table offset
; NOTA32-NEXT:    .secidx	{{\.?}}Ltmp4                  [[COMMENT]] Branch section index
; A32-NEXT:       .secidx	.LCPI0_1                      [[COMMENT]] Branch section index
; CHECK-NEXT:     .secidx	{{\.?}}LJTI0_1                [[COMMENT]] Table section index
; CHECK-NEXT:     [[INT32]]	5                           [[COMMENT]] Entries count
; CHECK-NOT:      [[INT16]]	4441                        [[COMMENT]] Record kind: S_ARMSWITCHTABLE

; Verify CodeView as dumped by llvm-readobj
; CV:      Subsection [
; CV:         SubSectionType: Symbols (0xF1)
; CV:         GlobalProcIdSym {
; CV:           DisplayName: func
; CV-NOT:     GlobalProcIdSym
; CV:           JumpTableSym {
; CV-NEXT:        Kind: S_ARMSWITCHTABLE (0x1159)
; CV-NEXT:        BaseOffset: 0x0
; CV-NEXT:        BaseSegment: 0
; CV-NEXT:        SwitchType: Int32 (0x4)
; CV-NEXT:        BranchOffset: 0x23
; CV-NEXT:        TableOffset: 0x0
; CV-NEXT:        BranchSegment: 0
; CV-NEXT:        TableSegment: 0
; CV-NEXT:        EntriesCount: 4
; CV-NEXT:      }
; CV-NEXT:      JumpTableSym {
; CV-NEXT:        Kind: S_ARMSWITCHTABLE (0x1159)
; CV-NEXT:        BaseOffset: 0x10
; CV-NEXT:        BaseSegment: 0
; CV-NEXT:        SwitchType: Int32 (0x4)
; CV-NEXT:        BranchOffset: 0x5A
; CV-NEXT:        TableOffset: 0x10
; CV-NEXT:        BranchSegment: 0
; CV-NEXT:        TableSegment: 0
; CV-NEXT:        EntriesCount: 5
; CV-NEXT:      }
; CV-NOT:       JumpTableSym {

source_filename = ".\\jump-table.cpp"
target datalayout = "e-m:w-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-pc-windows-msvc19.35.32216"

; Function Attrs: mustprogress noinline optnone uwtable
define dso_local void @func(i32 noundef %0) #0 !dbg !8 {
  %2 = alloca i32, align 4
  store i32 %0, ptr %2, align 4
  call void @llvm.dbg.declare(metadata ptr %2, metadata !14, metadata !DIExpression()), !dbg !15
  %3 = load i32, ptr %2, align 4, !dbg !16
  switch i32 %3, label %8 [
    i32 0, label %4
    i32 1, label %5
    i32 2, label %6
    i32 3, label %7
  ], !dbg !16

4:                                                ; preds = %1
  call void @f1(), !dbg !17
  br label %8, !dbg !17

5:                                                ; preds = %1
  call void @f2(), !dbg !19
  br label %8, !dbg !19

6:                                                ; preds = %1
  call void @f3(), !dbg !20
  br label %8, !dbg !20

7:                                                ; preds = %1
  call void @f4(), !dbg !21
  br label %8, !dbg !21

8:                                                ; preds = %1, %7, %6, %5, %4
  %9 = load i32, ptr %2, align 4, !dbg !22
  switch i32 %9, label %15 [
    i32 1, label %10
    i32 2, label %11
    i32 3, label %12
    i32 4, label %13
    i32 5, label %14
  ], !dbg !22

10:                                               ; preds = %8
  call void @f2(), !dbg !23
  br label %15, !dbg !23

11:                                               ; preds = %8
  call void @f3(), !dbg !25
  br label %15, !dbg !25

12:                                               ; preds = %8
  call void @f4(), !dbg !26
  br label %15, !dbg !26

13:                                               ; preds = %8
  call void @f5(), !dbg !27
  br label %15, !dbg !27

14:                                               ; preds = %8
  call void @f1(), !dbg !28
  br label %15, !dbg !28

15:                                               ; preds = %8, %14, %13, %12, %11, %10
  ret void, !dbg !29
}

; Function Attrs: nocallback nofree nosync nounwind readnone speculatable willreturn
declare void @llvm.dbg.declare(metadata, metadata, metadata) #1

declare dso_local void @f1() #2

declare dso_local void @f2() #2

declare dso_local void @f3() #2

declare dso_local void @f4() #2

declare dso_local void @f5() #2

attributes #0 = { mustprogress noinline optnone uwtable "frame-pointer"="none" "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
attributes #1 = { nocallback nofree nosync nounwind readnone speculatable willreturn }
attributes #2 = { "frame-pointer"="none" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }

!llvm.dbg.cu = !{!0}
!llvm.module.flags = !{!2, !3, !4, !5, !6}
!llvm.ident = !{!7}

!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus_11, file: !1, producer: "clang version 15.0.1", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, splitDebugInlining: false, nameTableKind: None)
!1 = !DIFile(filename: "jump-table.cpp", directory: "C:\\llvm", checksumkind: CSK_MD5, checksum: "35610c7104c8080f83e2bf6a02dabfc9")
!2 = !{i32 2, !"CodeView", i32 1}
!3 = !{i32 2, !"Debug Info Version", i32 3}
!4 = !{i32 1, !"wchar_size", i32 2}
!5 = !{i32 7, !"PIC Level", i32 2}
!6 = !{i32 7, !"uwtable", i32 2}
!7 = !{!"clang version 15.0.1"}
!8 = distinct !DISubprogram(name: "func", scope: !9, file: !9, line: 6, type: !10, scopeLine: 6, flags: DIFlagPrototyped, spFlags: DISPFlagDefinition, unit: !0, retainedNodes: !13)
!9 = !DIFile(filename: ".\\jump-table.cpp", directory: "C:\\llvm", checksumkind: CSK_MD5, checksum: "35610c7104c8080f83e2bf6a02dabfc9")
!10 = !DISubroutineType(types: !11)
!11 = !{null, !12}
!12 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
!13 = !{}
!14 = !DILocalVariable(name: "i", arg: 1, scope: !8, file: !9, line: 6, type: !12)
!15 = !DILocation(line: 6, scope: !8)
!16 = !DILocation(line: 7, scope: !8)
!17 = !DILocation(line: 8, scope: !18)
!18 = distinct !DILexicalBlock(scope: !8, file: !9, line: 7)
!19 = !DILocation(line: 9, scope: !18)
!20 = !DILocation(line: 10, scope: !18)
!21 = !DILocation(line: 11, scope: !18)
!22 = !DILocation(line: 13, scope: !8)
!23 = !DILocation(line: 14, scope: !24)
!24 = distinct !DILexicalBlock(scope: !8, file: !9, line: 13)
!25 = !DILocation(line: 15, scope: !24)
!26 = !DILocation(line: 16, scope: !24)
!27 = !DILocation(line: 17, scope: !24)
!28 = !DILocation(line: 18, scope: !24)
!29 = !DILocation(line: 20, scope: !8)