aboutsummaryrefslogtreecommitdiffstats
path: root/unmaintained/llvm3.9/rust-lang-llvm-pr53.patch
blob: 47b44808ed76f4e27224f2c8220466f2bac0ac3f (plain)
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
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
From 0d4331af6e01235479e44f9775b3fde9e19200a3 Mon Sep 17 00:00:00 2001
From: Keith Walker <kwalker@arm.com>
Date: Tue, 27 Sep 2016 16:46:07 +0000
Subject: [rust-lang/llvm#53 1/2] Propagate DBG_VALUE entries when there are
 unvisited predecessors

Variables are sometimes missing their debug location information in
blocks in which the variables should be available. This would occur
when one or more predecessor blocks had not yet been visited by the
routine which propagated the information from predecessor blocks.

This is addressed by only considering predecessor blocks which have
already been visited.

The solution to this problem was suggested by Daniel Berlin on the
LLVM developer mailing list.

Differential Revision: https://reviews.llvm.org/D24927


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@282506 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/CodeGen/LiveDebugValues.cpp          |  34 ++--
 test/CodeGen/ARM/dbg-range-extension.mir | 282 +++++++++++++++++++++++++++++++
 2 files changed, 306 insertions(+), 10 deletions(-)
 create mode 100644 test/CodeGen/ARM/dbg-range-extension.mir

diff --git a/lib/CodeGen/LiveDebugValues.cpp b/lib/CodeGen/LiveDebugValues.cpp
index 4ff88d528108..4cadd5855ed5 100644
--- a/lib/CodeGen/LiveDebugValues.cpp
+++ b/lib/CodeGen/LiveDebugValues.cpp
@@ -201,7 +201,8 @@ private:
                 VarLocInMBB &OutLocs, VarLocMap &VarLocIDs);
 
   bool join(MachineBasicBlock &MBB, VarLocInMBB &OutLocs, VarLocInMBB &InLocs,
-            const VarLocMap &VarLocIDs);
+            const VarLocMap &VarLocIDs,
+            SmallPtrSet<const MachineBasicBlock *, 16> &Visited);
 
   bool ExtendRanges(MachineFunction &MF);
 
@@ -368,7 +369,8 @@ bool LiveDebugValues::transfer(MachineInstr &MI, OpenRangesSet &OpenRanges,
 /// inserting a new DBG_VALUE instruction at the start of the @MBB - if the same
 /// source variable in all the predecessors of @MBB reside in the same location.
 bool LiveDebugValues::join(MachineBasicBlock &MBB, VarLocInMBB &OutLocs,
-                           VarLocInMBB &InLocs, const VarLocMap &VarLocIDs) {
+                           VarLocInMBB &InLocs, const VarLocMap &VarLocIDs,
+                           SmallPtrSet<const MachineBasicBlock *, 16> &Visited) {
   DEBUG(dbgs() << "join MBB: " << MBB.getName() << "\n");
   bool Changed = false;
 
@@ -376,21 +378,32 @@ bool LiveDebugValues::join(MachineBasicBlock &MBB, VarLocInMBB &OutLocs,
 
   // For all predecessors of this MBB, find the set of VarLocs that
   // can be joined.
+  int NumVisited = 0;
   for (auto p : MBB.predecessors()) {
+    // Ignore unvisited predecessor blocks.  As we are processing
+    // the blocks in reverse post-order any unvisited block can
+    // be considered to not remove any incoming values.
+    if (!Visited.count(p))
+      continue;
     auto OL = OutLocs.find(p);
     // Join is null in case of empty OutLocs from any of the pred.
     if (OL == OutLocs.end())
       return false;
 
-    // Just copy over the Out locs to incoming locs for the first predecessor.
-    if (p == *MBB.pred_begin()) {
+    // Just copy over the Out locs to incoming locs for the first visited
+    // predecessor, and for all other predecessors join the Out locs.
+    if (!NumVisited)
       InLocsT = OL->second;
-      continue;
-    }
-    // Join with this predecessor.
-    InLocsT &= OL->second;
+    else
+      InLocsT &= OL->second;
+    NumVisited++;
   }
 
+  // As we are processing blocks in reverse post-order we
+  // should have processed at least one predecessor, unless it
+  // is the entry block which has no predecessor.
+  assert((NumVisited || MBB.pred_empty()) &&
+         "Should have processed at least one predecessor");
   if (InLocsT.empty())
     return false;
 
@@ -463,6 +476,7 @@ bool LiveDebugValues::ExtendRanges(MachineFunction &MF) {
   // To solve it, we perform join() and transfer() using the two worklist method
   // until the ranges converge.
   // Ranges have converged when both worklists are empty.
+  SmallPtrSet<const MachineBasicBlock *, 16> Visited;
   while (!Worklist.empty() || !Pending.empty()) {
     // We track what is on the pending worklist to avoid inserting the same
     // thing twice.  We could avoid this with a custom priority queue, but this
@@ -471,8 +485,8 @@ bool LiveDebugValues::ExtendRanges(MachineFunction &MF) {
     while (!Worklist.empty()) {
       MachineBasicBlock *MBB = OrderToBB[Worklist.top()];
       Worklist.pop();
-      MBBJoined = join(*MBB, OutLocs, InLocs, VarLocIDs);
-
+      MBBJoined = join(*MBB, OutLocs, InLocs, VarLocIDs, Visited);
+      Visited.insert(MBB);
       if (MBBJoined) {
         MBBJoined = false;
         Changed = true;
diff --git a/test/CodeGen/ARM/dbg-range-extension.mir b/test/CodeGen/ARM/dbg-range-extension.mir
new file mode 100644
index 000000000000..b18f56197948
--- /dev/null
+++ b/test/CodeGen/ARM/dbg-range-extension.mir
@@ -0,0 +1,282 @@
+# RUN: llc -mtriple=arm-eabi -run-pass=livedebugvalues %s -o - | FileCheck %s
+#
+# Check that the debug information for variables are propagated into the correct blocks.
+#
+# Generated from the C source:
+#
+# int func2(int,  int);
+# void func(int a) {
+#   int b = func2(10, 11);
+#   if (a) {
+#     int c = func2(12, 13);
+#     for(int i = 1; i < a; i++) {
+#       func2(i, i+b);
+#     }
+#     func2(b,c);
+#   }
+#   func2(b,a);
+# }
+
+# CHECK: [[VAR_A:![0-9]+]] = !DILocalVariable(name: "a",
+# CHECK: [[VAR_B:![0-9]+]] = !DILocalVariable(name: "b",
+# CHECK: [[VAR_C:![0-9]+]] = !DILocalVariable(name: "c",
+# CHECK: [[VAR_I:![0-9]+]] = !DILocalVariable(name: "i",
+
+# CHECK: bb.0.entry
+# CHECK: DBG_VALUE debug-use %r0, debug-use _, [[VAR_A]]
+# CHECK: DBG_VALUE debug-use [[REG_A:%r[0-9]+]], debug-use _, [[VAR_A]]
+# CHECK: DBG_VALUE debug-use [[REG_B:%r[0-9]+]], debug-use _, [[VAR_B]]
+
+# CHECK: bb.1.if.then
+# CHECK: DBG_VALUE debug-use [[REG_B]], debug-use _, [[VAR_B]]
+# CHECK: DBG_VALUE debug-use [[REG_A]], debug-use _, [[VAR_A]]
+# CHECK: DBG_VALUE debug-use [[REG_C:%r[0-9]+]], debug-use _, [[VAR_C]]
+# CHECK: DBG_VALUE 1, 0, [[VAR_I]]
+
+# CHECK: bb.2.for.body
+# CHECK: DBG_VALUE debug-use [[REG_I:%r[0-9]+]], debug-use _, [[VAR_I]]
+# CHECK: DBG_VALUE debug-use [[REG_C]], debug-use _, [[VAR_C]]
+# CHECK: DBG_VALUE debug-use [[REG_B]], debug-use _, [[VAR_B]]
+# CHECK: DBG_VALUE debug-use [[REG_A]], debug-use _, [[VAR_A]]
+# CHECK: DBG_VALUE debug-use [[REG_I]], debug-use _, [[VAR_I]]
+
+# CHECK: bb.3.for.cond
+# CHECK: DBG_VALUE debug-use [[REG_C]], debug-use _, [[VAR_C]]
+# CHECK: DBG_VALUE debug-use [[REG_B]], debug-use _, [[VAR_B]]
+# CHECK: DBG_VALUE debug-use [[REG_A]], debug-use _, [[VAR_A]]
+# CHECK: DBG_VALUE debug-use [[REG_I]], debug-use _, [[VAR_I]]
+
+# CHECK: bb.4.for.cond.cleanup
+# CHECK: DBG_VALUE debug-use [[REG_I]], debug-use _, [[VAR_I]]
+# CHECK: DBG_VALUE debug-use [[REG_C]], debug-use _, [[VAR_C]]
+# CHECK: DBG_VALUE debug-use [[REG_B]], debug-use _, [[VAR_B]]
+# CHECK: DBG_VALUE debug-use [[REG_A]], debug-use _, [[VAR_A]]
+
+# CHECK: bb.5.if.end
+# CHECK: DBG_VALUE debug-use [[REG_B]], debug-use _, [[VAR_B]]
+# CHECK: DBG_VALUE debug-use [[REG_A]], debug-use _, [[VAR_A]]
+--- |
+  ; ModuleID = '/data/kwalker/work/OpenSource-llvm/llvm/test/CodeGen/ARM/dbg-range-extension.ll'
+  source_filename = "/data/kwalker/work/OpenSource-llvm/llvm/test/CodeGen/ARM/dbg-range-extension.ll"
+  target datalayout = "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64"
+  target triple = "arm---eabi"
+  
+  ; Function Attrs: minsize nounwind optsize
+  define void @func(i32 %a) local_unnamed_addr #0 !dbg !8 {
+  entry:
+    tail call void @llvm.dbg.value(metadata i32 %a, i64 0, metadata !13, metadata !20), !dbg !21
+    %call = tail call i32 @func2(i32 10, i32 11) #0, !dbg !22
+    tail call void @llvm.dbg.value(metadata i32 %call, i64 0, metadata !14, metadata !20), !dbg !23
+    %tobool = icmp eq i32 %a, 0, !dbg !24
+    br i1 %tobool, label %if.end, label %if.then, !dbg !25
+  
+  if.then:                                          ; preds = %entry
+    %call1 = tail call i32 @func2(i32 12, i32 13) #0, !dbg !26
+    tail call void @llvm.dbg.value(metadata i32 %call1, i64 0, metadata !15, metadata !20), !dbg !27
+    tail call void @llvm.dbg.value(metadata i32 1, i64 0, metadata !18, metadata !20), !dbg !28
+    br label %for.cond, !dbg !29
+  
+  for.cond:                                         ; preds = %for.body, %if.then
+    %i.0 = phi i32 [ 1, %if.then ], [ %inc, %for.body ]
+    tail call void @llvm.dbg.value(metadata i32 %i.0, i64 0, metadata !18, metadata !20), !dbg !28
+    %cmp = icmp slt i32 %i.0, %a, !dbg !30
+    br i1 %cmp, label %for.body, label %for.cond.cleanup, !dbg !33
+  
+  for.cond.cleanup:                                 ; preds = %for.cond
+    %call3 = tail call i32 @func2(i32 %call, i32 %call1) #0, !dbg !34
+    br label %if.end, !dbg !35
+  
+  for.body:                                         ; preds = %for.cond
+    %0 = add i32 %call, %i.0, !dbg !36
+    %call2 = tail call i32 @func2(i32 %i.0, i32 %0) #0, !dbg !36
+    %inc = add nuw nsw i32 %i.0, 1, !dbg !38
+    tail call void @llvm.dbg.value(metadata i32 %inc, i64 0, metadata !18, metadata !20), !dbg !28
+    br label %for.cond, !dbg !40, !llvm.loop !41
+  
+  if.end:                                           ; preds = %for.cond.cleanup, %entry
+    %call4 = tail call i32 @func2(i32 %call, i32 %a) #0, !dbg !43
+    ret void, !dbg !44
+  }
+  
+  ; Function Attrs: minsize optsize
+  declare i32 @func2(i32, i32) local_unnamed_addr #1
+  
+  ; Function Attrs: nounwind readnone
+  declare void @llvm.dbg.value(metadata, i64, metadata, metadata) #2
+  
+  ; Function Attrs: nounwind
+  declare void @llvm.stackprotector(i8*, i8**) #3
+  
+  attributes #0 = { minsize nounwind optsize }
+  attributes #1 = { minsize optsize }
+  attributes #2 = { nounwind readnone }
+  attributes #3 = { nounwind }
+  
+  !llvm.dbg.cu = !{!0}
+  !llvm.module.flags = !{!3, !4, !5, !6}
+  !llvm.ident = !{!7}
+  
+  !0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2)
+  !1 = !DIFile(filename: "loop.c", directory: "/tmp")
+  !2 = !{}
+  !3 = !{i32 2, !"Dwarf Version", i32 4}
+  !4 = !{i32 2, !"Debug Info Version", i32 3}
+  !5 = !{i32 1, !"wchar_size", i32 4}
+  !6 = !{i32 1, !"min_enum_size", i32 4}
+  !7 = !{!"clang version 4.0.0 (http://llvm.org/git/clang.git b8f10df3679b36f51e1de7c4351b82d297825089) (http://llvm.org/git/llvm.git c2a5d16d1e3b8c49f5bbb1ff87a76ac4f88edb89)"}
+  !8 = distinct !DISubprogram(name: "func", scope: !1, file: !1, line: 2, type: !9, isLocal: false, isDefinition: true, scopeLine: 2, flags: DIFlagPrototyped, isOptimized: true, unit: !0, variables: !12)
+  !9 = !DISubroutineType(types: !10)
+  !10 = !{null, !11}
+  !11 = !DIBasicType(name: "int", size: 32, align: 32, encoding: DW_ATE_signed)
+  !12 = !{!13, !14, !15, !18}
+  !13 = !DILocalVariable(name: "a", arg: 1, scope: !8, file: !1, line: 2, type: !11)
+  !14 = !DILocalVariable(name: "b", scope: !8, file: !1, line: 3, type: !11)
+  !15 = !DILocalVariable(name: "c", scope: !16, file: !1, line: 5, type: !11)
+  !16 = distinct !DILexicalBlock(scope: !17, file: !1, line: 4, column: 9)
+  !17 = distinct !DILexicalBlock(scope: !8, file: !1, line: 4, column: 6)
+  !18 = !DILocalVariable(name: "i", scope: !19, file: !1, line: 6, type: !11)
+  !19 = distinct !DILexicalBlock(scope: !16, file: !1, line: 6, column: 3)
+  !20 = !DIExpression()
+  !21 = !DILocation(line: 2, column: 15, scope: !8)
+  !22 = !DILocation(line: 3, column: 17, scope: !8)
+  !23 = !DILocation(line: 3, column: 13, scope: !8)
+  !24 = !DILocation(line: 4, column: 6, scope: !17)
+  !25 = !DILocation(line: 4, column: 6, scope: !8)
+  !26 = !DILocation(line: 5, column: 11, scope: !16)
+  !27 = !DILocation(line: 5, column: 7, scope: !16)
+  !28 = !DILocation(line: 6, column: 11, scope: !19)
+  !29 = !DILocation(line: 6, column: 7, scope: !19)
+  !30 = !DILocation(line: 6, column: 20, scope: !31)
+  !31 = !DILexicalBlockFile(scope: !32, file: !1, discriminator: 1)
+  !32 = distinct !DILexicalBlock(scope: !19, file: !1, line: 6, column: 3)
+  !33 = !DILocation(line: 6, column: 3, scope: !31)
+  !34 = !DILocation(line: 9, column: 3, scope: !16)
+  !35 = !DILocation(line: 10, column: 2, scope: !16)
+  !36 = !DILocation(line: 7, column: 4, scope: !37)
+  !37 = distinct !DILexicalBlock(scope: !32, file: !1, line: 6, column: 30)
+  !38 = !DILocation(line: 6, column: 26, scope: !39)
+  !39 = !DILexicalBlockFile(scope: !32, file: !1, discriminator: 3)
+  !40 = !DILocation(line: 6, column: 3, scope: !39)
+  !41 = distinct !{!41, !42}
+  !42 = !DILocation(line: 6, column: 3, scope: !16)
+  !43 = !DILocation(line: 11, column: 2, scope: !8)
+  !44 = !DILocation(line: 12, column: 1, scope: !8)
+
+...
+---
+name:            func
+alignment:       2
+exposesReturnsTwice: false
+legalized:       false
+regBankSelected: false
+selected:        false
+tracksRegLiveness: false
+liveins:         
+  - { reg: '%r0' }
+calleeSavedRegisters: [ '%lr', '%d8', '%d9', '%d10', '%d11', '%d12', '%d13', 
+                        '%d14', '%d15', '%q4', '%q5', '%q6', '%q7', '%r4', 
+                        '%r5', '%r6', '%r7', '%r8', '%r9', '%r10', '%r11', 
+                        '%s16', '%s17', '%s18', '%s19', '%s20', '%s21', 
+                        '%s22', '%s23', '%s24', '%s25', '%s26', '%s27', 
+                        '%s28', '%s29', '%s30', '%s31', '%d8_d10', '%d9_d11', 
+                        '%d10_d12', '%d11_d13', '%d12_d14', '%d13_d15', 
+                        '%q4_q5', '%q5_q6', '%q6_q7', '%q4_q5_q6_q7', '%r4_r5', 
+                        '%r6_r7', '%r8_r9', '%r10_r11', '%d8_d9_d10', '%d9_d10_d11', 
+                        '%d10_d11_d12', '%d11_d12_d13', '%d12_d13_d14', 
+                        '%d13_d14_d15', '%d8_d10_d12', '%d9_d11_d13', '%d10_d12_d14', 
+                        '%d11_d13_d15', '%d8_d10_d12_d14', '%d9_d11_d13_d15', 
+                        '%d9_d10', '%d11_d12', '%d13_d14', '%d9_d10_d11_d12', 
+                        '%d11_d12_d13_d14' ]
+frameInfo:       
+  isFrameAddressTaken: false
+  isReturnAddressTaken: false
+  hasStackMap:     false
+  hasPatchPoint:   false
+  stackSize:       24
+  offsetAdjustment: 0
+  maxAlignment:    4
+  adjustsStack:    true
+  hasCalls:        true
+  maxCallFrameSize: 0
+  hasOpaqueSPAdjustment: false
+  hasVAStart:      false
+  hasMustTailInVarArgFunc: false
+stack:           
+  - { id: 0, type: spill-slot, offset: -4, size: 4, alignment: 4, callee-saved-register: '%lr' }
+  - { id: 1, type: spill-slot, offset: -8, size: 4, alignment: 4, callee-saved-register: '%r11' }
+  - { id: 2, type: spill-slot, offset: -12, size: 4, alignment: 4, callee-saved-register: '%r7' }
+  - { id: 3, type: spill-slot, offset: -16, size: 4, alignment: 4, callee-saved-register: '%r6' }
+  - { id: 4, type: spill-slot, offset: -20, size: 4, alignment: 4, callee-saved-register: '%r5' }
+  - { id: 5, type: spill-slot, offset: -24, size: 4, alignment: 4, callee-saved-register: '%r4' }
+body:             |
+  bb.0.entry:
+    successors: %bb.5.if.end, %bb.1.if.then
+    liveins: %r0, %r4, %r5, %r6, %r7, %r11, %lr
+  
+    %sp = frame-setup STMDB_UPD %sp, 14, _, killed %r4, killed %r5, killed %r6, killed %r7, killed %r11, killed %lr
+    frame-setup CFI_INSTRUCTION def_cfa_offset 24
+    frame-setup CFI_INSTRUCTION offset %lr, -4
+    frame-setup CFI_INSTRUCTION offset %r11, -8
+    frame-setup CFI_INSTRUCTION offset %r7, -12
+    frame-setup CFI_INSTRUCTION offset %r6, -16
+    frame-setup CFI_INSTRUCTION offset %r5, -20
+    frame-setup CFI_INSTRUCTION offset %r4, -24
+    DBG_VALUE debug-use %r0, debug-use _, !13, !20, debug-location !21
+    %r4 = MOVr killed %r0, 14, _, _
+    DBG_VALUE debug-use %r4, debug-use _, !13, !20, debug-location !21
+    %r0 = MOVi 10, 14, _, _, debug-location !22
+    %r1 = MOVi 11, 14, _, _, debug-location !22
+    BL @func2, csr_aapcs, implicit-def dead %lr, implicit %sp, implicit killed %r0, implicit killed %r1, implicit-def %sp, implicit-def %r0, debug-location !22
+    %r5 = MOVr killed %r0, 14, _, _, debug-location !22
+    DBG_VALUE debug-use %r5, debug-use _, !14, !20, debug-location !23
+    CMPri %r4, 0, 14, _, implicit-def %cpsr, debug-location !25
+    Bcc %bb.5.if.end, 0, killed %cpsr
+  
+  bb.1.if.then:
+    successors: %bb.3.for.cond
+    liveins: %r4, %r5
+  
+    %r0 = MOVi 12, 14, _, _, debug-location !26
+    %r1 = MOVi 13, 14, _, _, debug-location !26
+    BL @func2, csr_aapcs, implicit-def dead %lr, implicit %sp, implicit killed %r0, implicit killed %r1, implicit-def %sp, implicit-def %r0, debug-location !26
+    %r6 = MOVr killed %r0, 14, _, _, debug-location !26
+    DBG_VALUE debug-use %r6, debug-use _, !15, !20, debug-location !27
+    %r7 = MOVi 1, 14, _, _
+    DBG_VALUE 1, 0, !18, !20, debug-location !28
+    B %bb.3.for.cond
+  
+  bb.2.for.body:
+    successors: %bb.3.for.cond
+    liveins: %r4, %r5, %r6, %r7
+  
+    %r1 = ADDrr %r5, %r7, 14, _, _, debug-location !36
+    %r0 = MOVr %r7, 14, _, _, debug-location !36
+    BL @func2, csr_aapcs, implicit-def dead %lr, implicit %sp, implicit killed %r0, implicit killed %r1, implicit-def %sp, implicit-def dead %r0, debug-location !36
+    %r7 = ADDri killed %r7, 1, 14, _, _, debug-location !38
+    DBG_VALUE debug-use %r7, debug-use _, !18, !20, debug-location !28
+  
+  bb.3.for.cond:
+    successors: %bb.2.for.body, %bb.4.for.cond.cleanup
+    liveins: %r4, %r5, %r6, %r7
+  
+    DBG_VALUE debug-use %r7, debug-use _, !18, !20, debug-location !28
+    CMPrr %r7, %r4, 14, _, implicit-def %cpsr, debug-location !33
+    Bcc %bb.2.for.body, 11, killed %cpsr, debug-location !33
+  
+  bb.4.for.cond.cleanup:
+    successors: %bb.5.if.end
+    liveins: %r4, %r5, %r6
+  
+    %r0 = MOVr %r5, 14, _, _, debug-location !34
+    %r1 = MOVr killed %r6, 14, _, _, debug-location !34
+    BL @func2, csr_aapcs, implicit-def dead %lr, implicit %sp, implicit killed %r0, implicit killed %r1, implicit-def %sp, implicit-def dead %r0, debug-location !34
+  
+  bb.5.if.end:
+    liveins: %r4, %r5
+  
+    %r0 = MOVr killed %r5, 14, _, _, debug-location !43
+    %r1 = MOVr killed %r4, 14, _, _, debug-location !43
+    %sp = LDMIA_UPD %sp, 14, _, def %r4, def %r5, def %r6, def %r7, def %r11, def %lr, debug-location !43
+    TAILJMPd @func2, implicit %sp, implicit %sp, implicit killed %r0, implicit killed %r1, debug-location !43
+
+...
-- 
2.7.4

From 8a0fc26559123bb6eab3ceae93d5a2c94943614b Mon Sep 17 00:00:00 2001
From: Adrian Prantl <aprantl@apple.com>
Date: Wed, 28 Sep 2016 17:51:14 +0000
Subject: [rust-lang/llvm#53 2/2] Teach LiveDebugValues about lexical scopes.

This addresses PR26055 LiveDebugValues is very slow.

Contrary to the old LiveDebugVariables pass LiveDebugValues currently
doesn't look at the lexical scopes before inserting a DBG_VALUE
intrinsic. This means that we often propagate DBG_VALUEs much further
down than necessary. This is especially noticeable in large C++
functions with many inlined method calls that all use the same
"this"-pointer.

For example, in the following code it makes no sense to propagate the
inlined variable a from the first inlined call to f() into any of the
subsequent basic blocks, because the variable will always be out of
scope:

void sink(int a);
void __attribute((always_inline)) f(int a) { sink(a); }
void foo(int i) {
   f(i);
   if (i)
     f(i);
   f(i);
}

This patch reuses the LexicalScopes infrastructure we have for
LiveDebugVariables to take this into account.

The effect on compile time and memory consumption is quite noticeable:
I tested a benchmark that is a large C++ source with an enormous
amount of inlined "this"-pointers that would previously eat >24GiB
(most of them for DBG_VALUE intrinsics) and whose compile time was
dominated by LiveDebugValues. With this patch applied the memory
consumption is 1GiB and 1.7% of the time is spent in LiveDebugValues.

https://reviews.llvm.org/D24994
Thanks to Daniel Berlin and Keith Walker for reviewing!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@282611 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/CodeGen/LiveDebugValues.cpp                  |  51 ++++-
 test/CodeGen/ARM/dbg-range-extension.mir         |   1 -
 test/DebugInfo/COFF/register-variables.ll        |   8 +-
 test/DebugInfo/MIR/X86/livedebugvalues-limit.mir | 228 +++++++++++++++++++++++
 test/DebugInfo/X86/fission-ranges.ll             |   6 +-
 5 files changed, 278 insertions(+), 16 deletions(-)
 create mode 100644 test/DebugInfo/MIR/X86/livedebugvalues-limit.mir

diff --git a/lib/CodeGen/LiveDebugValues.cpp b/lib/CodeGen/LiveDebugValues.cpp
index 4cadd5855ed5..969944eb24a2 100644
--- a/lib/CodeGen/LiveDebugValues.cpp
+++ b/lib/CodeGen/LiveDebugValues.cpp
@@ -23,6 +23,7 @@
 #include "llvm/ADT/SparseBitVector.h"
 #include "llvm/ADT/Statistic.h"
 #include "llvm/ADT/UniqueVector.h"
+#include "llvm/CodeGen/LexicalScopes.h"
 #include "llvm/CodeGen/MachineFunction.h"
 #include "llvm/CodeGen/MachineFunctionPass.h"
 #include "llvm/CodeGen/MachineInstrBuilder.h"
@@ -60,6 +61,26 @@ class LiveDebugValues : public MachineFunctionPass {
 private:
   const TargetRegisterInfo *TRI;
   const TargetInstrInfo *TII;
+  LexicalScopes LS;
+
+  /// Keeps track of lexical scopes associated with a user value's source
+  /// location.
+  class UserValueScopes {
+    DebugLoc DL;
+    LexicalScopes &LS;
+    SmallPtrSet<const MachineBasicBlock *, 4> LBlocks;
+
+  public:
+    UserValueScopes(DebugLoc D, LexicalScopes &L) : DL(std::move(D)), LS(L) {}
+
+    /// Return true if current scope dominates at least one machine
+    /// instruction in a given machine basic block.
+    bool dominates(MachineBasicBlock *MBB) {
+      if (LBlocks.empty())
+        LS.getMachineBasicBlocks(DL, LBlocks);
+      return LBlocks.count(MBB) != 0 || LS.dominates(DL, MBB);
+    }
+  };
 
   /// Based on std::pair so it can be used as an index into a DenseMap.
   typedef std::pair<const DILocalVariable *, const DILocation *>
@@ -83,7 +104,7 @@ private:
   struct VarLoc {
     const DebugVariable Var;
     const MachineInstr &MI; ///< Only used for cloning a new DBG_VALUE.
-
+    mutable UserValueScopes UVS;
     enum { InvalidKind = 0, RegisterKind } Kind;
 
     /// The value location. Stored separately to avoid repeatedly
@@ -96,9 +117,9 @@ private:
       uint64_t Hash;
     } Loc;
 
-    VarLoc(const MachineInstr &MI)
+    VarLoc(const MachineInstr &MI, LexicalScopes &LS)
         : Var(MI.getDebugVariable(), MI.getDebugLoc()->getInlinedAt()), MI(MI),
-          Kind(InvalidKind) {
+          UVS(MI.getDebugLoc(), LS), Kind(InvalidKind) {
       static_assert((sizeof(Loc) == sizeof(uint64_t)),
                     "hash does not cover all members of Loc");
       assert(MI.isDebugValue() && "not a DBG_VALUE");
@@ -125,6 +146,10 @@ private:
       return 0;
     }
 
+    /// Determine whether the lexical scope of this value's debug location
+    /// dominates MBB.
+    bool dominates(MachineBasicBlock &MBB) const { return UVS.dominates(&MBB); }
+
     void dump() const { MI.dump(); }
 
     bool operator==(const VarLoc &Other) const {
@@ -229,6 +254,7 @@ public:
   /// Calculate the liveness information for the given machine function.
   bool runOnMachineFunction(MachineFunction &MF) override;
 };
+
 } // namespace
 
 //===----------------------------------------------------------------------===//
@@ -295,7 +321,7 @@ void LiveDebugValues::transferDebugValue(const MachineInstr &MI,
   // Add the VarLoc to OpenRanges from this DBG_VALUE.
   // TODO: Currently handles DBG_VALUE which has only reg as location.
   if (isDbgValueDescribedByReg(MI)) {
-    VarLoc VL(MI);
+    VarLoc VL(MI, LS);
     unsigned ID = VarLocIDs.insert(VL);
     OpenRanges.insert(ID, VL.Var);
   }
@@ -399,6 +425,13 @@ bool LiveDebugValues::join(MachineBasicBlock &MBB, VarLocInMBB &OutLocs,
     NumVisited++;
   }
 
+  // Filter out DBG_VALUES that are out of scope.
+  VarLocSet KillSet;
+  for (auto ID : InLocsT)
+    if (!VarLocIDs[ID].dominates(MBB))
+      KillSet.set(ID);
+  InLocsT.intersectWithComplement(KillSet);
+
   // As we are processing blocks in reverse post-order we
   // should have processed at least one predecessor, unless it
   // is the entry block which has no predecessor.
@@ -519,12 +552,14 @@ bool LiveDebugValues::ExtendRanges(MachineFunction &MF) {
 }
 
 bool LiveDebugValues::runOnMachineFunction(MachineFunction &MF) {
+  if (!MF.getFunction()->getSubprogram())
+    // LiveDebugValues will already have removed all DBG_VALUEs.
+    return false;
+
   TRI = MF.getSubtarget().getRegisterInfo();
   TII = MF.getSubtarget().getInstrInfo();
+  LS.initialize(MF);
 
-  bool Changed = false;
-
-  Changed |= ExtendRanges(MF);
-
+  bool Changed = ExtendRanges(MF);
   return Changed;
 }
diff --git a/test/CodeGen/ARM/dbg-range-extension.mir b/test/CodeGen/ARM/dbg-range-extension.mir
index b18f56197948..466f69396948 100644
--- a/test/CodeGen/ARM/dbg-range-extension.mir
+++ b/test/CodeGen/ARM/dbg-range-extension.mir
@@ -47,7 +47,6 @@
 # CHECK: DBG_VALUE debug-use [[REG_I]], debug-use _, [[VAR_I]]
 
 # CHECK: bb.4.for.cond.cleanup
-# CHECK: DBG_VALUE debug-use [[REG_I]], debug-use _, [[VAR_I]]
 # CHECK: DBG_VALUE debug-use [[REG_C]], debug-use _, [[VAR_C]]
 # CHECK: DBG_VALUE debug-use [[REG_B]], debug-use _, [[VAR_B]]
 # CHECK: DBG_VALUE debug-use [[REG_A]], debug-use _, [[VAR_A]]
diff --git a/test/DebugInfo/COFF/register-variables.ll b/test/DebugInfo/COFF/register-variables.ll
index 9bb782853a3d..08246fef9603 100644
--- a/test/DebugInfo/COFF/register-variables.ll
+++ b/test/DebugInfo/COFF/register-variables.ll
@@ -37,8 +37,8 @@
 ; ASM:         #DEBUG_VALUE: c <- %EAX
 ; ASM:         testl   %esi, %esi
 ; ASM:         je      .LBB0_2
+; ASM: [[after_je:\.Ltmp.*]]:
 ; ASM: # BB#1:                                 # %if.then
-; ASM-DAG:     #DEBUG_VALUE: c <- %EAX
 ; ASM-DAG:     #DEBUG_VALUE: inlineinc:a <- %EAX
 ; ASM-DAG:     #DEBUG_VALUE: a <- %EAX
 ; ASM-DAG:     #DEBUG_VALUE: f:p <- %ESI
@@ -65,7 +65,7 @@
 ; ASM:         .cv_def_range    [[after_getint]] [[after_inc_eax]], "A\021\021\000\000\000"
 ; ASM:         .short  4414                    # Record kind: S_LOCAL
 ; ASM:         .asciz  "c"
-; ASM:         .cv_def_range    [[after_getint]] [[after_inc_eax]], "A\021\021\000\000\000"
+; ASM:         .cv_def_range    [[after_getint]] [[after_je]], "A\021\021\000\000\000"
 ; ASM:         .short  4414                    # Record kind: S_LOCAL
 ; ASM:         .asciz  "b"
 ; ASM:         .cv_def_range    [[after_inc_eax]] [[after_if]], "A\021\021\000\000\000"
@@ -132,7 +132,7 @@
 ; OBJ:     LocalVariableAddrRange {
 ; OBJ:       OffsetStart: .text+0xC
 ; OBJ:       ISectStart: 0x0
-; OBJ:       Range: 0x6
+; OBJ:       Range: 0x4
 ; OBJ:     }
 ; OBJ:   }
 ; OBJ:   Local {
@@ -143,7 +143,7 @@
 ; OBJ:   }
 ; OBJ:   DefRangeRegister {
 ; OBJ:     Register: 17
-; OBJ:     LocalVariableAddrRange {
+; OBJ:     MayHaveNoName: 0
 ; OBJ:       OffsetStart: .text+0x12
 ; OBJ:       ISectStart: 0x0
 ; OBJ:       Range: 0x6
diff --git a/test/DebugInfo/MIR/X86/livedebugvalues-limit.mir b/test/DebugInfo/MIR/X86/livedebugvalues-limit.mir
new file mode 100644
index 000000000000..4c87543636d5
--- /dev/null
+++ b/test/DebugInfo/MIR/X86/livedebugvalues-limit.mir
@@ -0,0 +1,228 @@
+--- |
+  ; RUN: llc -run-pass=livedebugvalues -march=x86-64 -o - %s | FileCheck %s
+  ; Created from:
+  ; void sink(int a);
+  ; void __attribute((always_inline)) f(int a) { sink(a); }
+  ; void foo(int i) {
+  ;   f(i);
+  ;   if (i)
+  ;     f(i);
+  ;   f(i);
+  ; }
+  ;
+  ; This test verifies that LiveDebugValues doesn't propagate DBG_VALUEs into
+  ; basic blocks that are beyond the scope of the source variable.
+  ;
+  ; CHECK:  bb.1.if.then:
+  ; CHECK:      DBG_VALUE debug-use %ebx, debug-use _, !19, !13, debug-location !20
+  ; CHECK-NOT:  DBG_VALUE debug-use %ebx, debug-use _, !12, !13, debug-location !21
+  ; CHECK:      DBG_VALUE debug-use %ebx, debug-use _, !12, !13, debug-location !27
+  ; CHECK: bb.2.if.end:
+  ; CHECK:     DBG_VALUE debug-use %ebx, debug-use _, !19, !13, debug-location !20
+  ; CHECK-NOT: DBG_VALUE debug-use %ebx, debug-use _, !12, !13, debug-location !21
+  ; CHECK:     DBG_VALUE debug-use %ebx, debug-use _, !12, !13, debug-location !31
+  ;
+  ; ModuleID = 'livedebugvalues-limit.ll'
+  source_filename = "livedebugvalues-limit.c"
+  target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
+  target triple = "x86_64-apple-macosx"
+  
+  ; Function Attrs: alwaysinline nounwind ssp uwtable
+  define void @f(i32 %a) local_unnamed_addr #0 !dbg !7 {
+  entry:
+    tail call void @llvm.dbg.value(metadata i32 %a, i64 0, metadata !12, metadata !13), !dbg !14
+    tail call void @sink(i32 %a) #4, !dbg !15
+    ret void, !dbg !16
+  }
+  
+  declare void @sink(i32) local_unnamed_addr
+  
+  ; Function Attrs: nounwind ssp uwtable
+  define void @foo(i32 %i) local_unnamed_addr #2 !dbg !17 {
+  entry:
+    tail call void @llvm.dbg.value(metadata i32 %i, i64 0, metadata !19, metadata !13), !dbg !20
+    tail call void @llvm.dbg.value(metadata i32 %i, i64 0, metadata !12, metadata !13) #4, !dbg !21
+    tail call void @sink(i32 %i) #4, !dbg !23
+    %tobool = icmp eq i32 %i, 0, !dbg !24
+    br i1 %tobool, label %if.end, label %if.then, !dbg !26
+  
+  if.then:                                          ; preds = %entry
+    tail call void @llvm.dbg.value(metadata i32 %i, i64 0, metadata !12, metadata !13) #4, !dbg !27
+    tail call void @sink(i32 %i) #4, !dbg !29
+    br label %if.end, !dbg !30
+  
+  if.end:                                           ; preds = %if.then, %entry
+    tail call void @llvm.dbg.value(metadata i32 %i, i64 0, metadata !12, metadata !13) #4, !dbg !31
+    tail call void @sink(i32 %i) #4, !dbg !33
+    ret void, !dbg !34
+  }
+  
+  ; Function Attrs: nounwind readnone
+  declare void @llvm.dbg.value(metadata, i64, metadata, metadata) #3
+  
+  ; Function Attrs: nounwind
+  declare void @llvm.stackprotector(i8*, i8**) #4
+  
+  attributes #0 = { alwaysinline nounwind ssp uwtable }
+  attributes #2 = { nounwind ssp uwtable }
+  attributes #3 = { nounwind readnone }
+  attributes #4 = { nounwind }
+  
+  !llvm.dbg.cu = !{!0}
+  !llvm.module.flags = !{!3, !4, !5}
+  !llvm.ident = !{!6}
+  
+  !0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang version 4.0.0 (trunk 281923) (llvm/trunk 281916)", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2)
+  !1 = !DIFile(filename: "livedebugvalues-limit.c", directory: "/Volumes/Fusion/Data/llvm")
+  !2 = !{}
+  !3 = !{i32 2, !"Dwarf Version", i32 4}
+  !4 = !{i32 2, !"Debug Info Version", i32 3}
+  !5 = !{i32 1, !"PIC Level", i32 2}
+  !6 = !{!"clang version 4.0.0 (trunk 281923) (llvm/trunk 281916)"}
+  !7 = distinct !DISubprogram(name: "f", scope: !1, file: !1, line: 3, type: !8, isLocal: false, isDefinition: true, scopeLine: 3, flags: DIFlagPrototyped, isOptimized: true, unit: !0, variables: !11)
+  !8 = !DISubroutineType(types: !9)
+  !9 = !{null, !10}
+  !10 = !DIBasicType(name: "int", size: 32, align: 32, encoding: DW_ATE_signed)
+  !11 = !{!12}
+  !12 = !DILocalVariable(name: "a", arg: 1, scope: !7, file: !1, line: 3, type: !10)
+  !13 = !DIExpression()
+  !14 = !DILocation(line: 3, column: 41, scope: !7)
+  !15 = !DILocation(line: 3, column: 46, scope: !7)
+  !16 = !DILocation(line: 3, column: 55, scope: !7)
+  !17 = distinct !DISubprogram(name: "foo", scope: !1, file: !1, line: 4, type: !8, isLocal: false, isDefinition: true, scopeLine: 4, flags: DIFlagPrototyped, isOptimized: true, unit: !0, variables: !18)
+  !18 = !{!19}
+  !19 = !DILocalVariable(name: "i", arg: 1, scope: !17, file: !1, line: 4, type: !10)
+  !20 = !DILocation(line: 4, column: 14, scope: !17)
+  !21 = !DILocation(line: 3, column: 41, scope: !7, inlinedAt: !22)
+  !22 = distinct !DILocation(line: 5, column: 3, scope: !17)
+  !23 = !DILocation(line: 3, column: 46, scope: !7, inlinedAt: !22)
+  !24 = !DILocation(line: 6, column: 7, scope: !25)
+  !25 = distinct !DILexicalBlock(scope: !17, file: !1, line: 6, column: 7)
+  !26 = !DILocation(line: 6, column: 7, scope: !17)
+  !27 = !DILocation(line: 3, column: 41, scope: !7, inlinedAt: !28)
+  !28 = distinct !DILocation(line: 7, column: 5, scope: !25)
+  !29 = !DILocation(line: 3, column: 46, scope: !7, inlinedAt: !28)
+  !30 = !DILocation(line: 7, column: 5, scope: !25)
+  !31 = !DILocation(line: 3, column: 41, scope: !7, inlinedAt: !32)
+  !32 = distinct !DILocation(line: 8, column: 3, scope: !17)
+  !33 = !DILocation(line: 3, column: 46, scope: !7, inlinedAt: !32)
+  !34 = !DILocation(line: 9, column: 1, scope: !17)
+
+...
+---
+name:            f
+alignment:       4
+exposesReturnsTwice: false
+legalized:       false
+regBankSelected: false
+selected:        false
+tracksRegLiveness: true
+liveins:         
+  - { reg: '%edi' }
+calleeSavedRegisters: [ '%bh', '%bl', '%bp', '%bpl', '%bx', '%ebp', '%ebx', 
+                        '%rbp', '%rbx', '%r12', '%r13', '%r14', '%r15', 
+                        '%r12b', '%r13b', '%r14b', '%r15b', '%r12d', '%r13d', 
+                        '%r14d', '%r15d', '%r12w', '%r13w', '%r14w', '%r15w' ]
+frameInfo:       
+  isFrameAddressTaken: false
+  isReturnAddressTaken: false
+  hasStackMap:     false
+  hasPatchPoint:   false
+  stackSize:       8
+  offsetAdjustment: 0
+  maxAlignment:    0
+  adjustsStack:    false
+  hasCalls:        false
+  maxCallFrameSize: 0
+  hasOpaqueSPAdjustment: false
+  hasVAStart:      false
+  hasMustTailInVarArgFunc: false
+fixedStack:      
+  - { id: 0, type: spill-slot, offset: -16, size: 8, alignment: 16 }
+body:             |
+  bb.0.entry:
+    liveins: %edi, %rbp
+  
+    frame-setup PUSH64r killed %rbp, implicit-def %rsp, implicit %rsp
+    CFI_INSTRUCTION def_cfa_offset 16
+    CFI_INSTRUCTION offset %rbp, -16
+    %rbp = frame-setup MOV64rr %rsp
+    CFI_INSTRUCTION def_cfa_register %rbp
+    DBG_VALUE debug-use %edi, debug-use _, !12, !13, debug-location !14
+    %rbp = POP64r implicit-def %rsp, implicit %rsp, debug-location !15
+    TAILJMPd64 @sink, csr_64, implicit %rsp, implicit %rsp, implicit %edi, debug-location !15
+
+...
+---
+name:            foo
+alignment:       4
+exposesReturnsTwice: false
+legalized:       false
+regBankSelected: false
+selected:        false
+tracksRegLiveness: true
+liveins:         
+  - { reg: '%edi' }
+calleeSavedRegisters: [ '%bh', '%bl', '%bp', '%bpl', '%bx', '%ebp', '%ebx', 
+                        '%rbp', '%rbx', '%r12', '%r13', '%r14', '%r15', 
+                        '%r12b', '%r13b', '%r14b', '%r15b', '%r12d', '%r13d', 
+                        '%r14d', '%r15d', '%r12w', '%r13w', '%r14w', '%r15w' ]
+frameInfo:       
+  isFrameAddressTaken: false
+  isReturnAddressTaken: false
+  hasStackMap:     false
+  hasPatchPoint:   false
+  stackSize:       24
+  offsetAdjustment: -8
+  maxAlignment:    0
+  adjustsStack:    true
+  hasCalls:        true
+  maxCallFrameSize: 0
+  hasOpaqueSPAdjustment: false
+  hasVAStart:      false
+  hasMustTailInVarArgFunc: false
+fixedStack:      
+  - { id: 0, type: spill-slot, offset: -24, size: 8, alignment: 8, callee-saved-register: '%rbx' }
+  - { id: 1, type: spill-slot, offset: -16, size: 8, alignment: 16 }
+body:             |
+  bb.0.entry:
+    successors: %bb.2.if.end, %bb.1.if.then
+    liveins: %edi, %rbx, %rbp
+  
+    frame-setup PUSH64r killed %rbp, implicit-def %rsp, implicit %rsp
+    CFI_INSTRUCTION def_cfa_offset 16
+    CFI_INSTRUCTION offset %rbp, -16
+    %rbp = frame-setup MOV64rr %rsp
+    CFI_INSTRUCTION def_cfa_register %rbp
+    frame-setup PUSH64r killed %rbx, implicit-def %rsp, implicit %rsp
+    frame-setup PUSH64r undef %rax, implicit-def %rsp, implicit %rsp
+    CFI_INSTRUCTION offset %rbx, -24
+    DBG_VALUE debug-use %edi, debug-use _, !19, !13, debug-location !20
+    %ebx = MOV32rr %edi
+    DBG_VALUE debug-use %ebx, debug-use _, !12, !13, debug-location !21
+    DBG_VALUE debug-use %ebx, debug-use _, !19, !13, debug-location !20
+    CALL64pcrel32 @sink, csr_64, implicit %rsp, implicit %edi, implicit-def %rsp, debug-location !23
+    TEST32rr %ebx, %ebx, implicit-def %eflags, debug-location !24
+    JE_1 %bb.2.if.end, implicit %eflags
+  
+  bb.1.if.then:
+    successors: %bb.2.if.end
+    liveins: %ebx, %rbp
+  
+    DBG_VALUE debug-use %ebx, debug-use _, !19, !13, debug-location !20
+    DBG_VALUE debug-use %ebx, debug-use _, !12, !13, debug-location !27
+    %edi = MOV32rr %ebx, debug-location !29
+    CALL64pcrel32 @sink, csr_64, implicit %rsp, implicit %edi, implicit-def %rsp, debug-location !29
+  
+  bb.2.if.end:
+    liveins: %ebx, %rbp
+  
+    DBG_VALUE debug-use %ebx, debug-use _, !19, !13, debug-location !20
+    %edi = MOV32rr killed %ebx, debug-location !33
+    %rsp = ADD64ri8 %rsp, 8, implicit-def dead %eflags, debug-location !33
+    DBG_VALUE debug-use %ebx, debug-use _, !12, !13, debug-location !31
+    %rbx = POP64r implicit-def %rsp, implicit %rsp, debug-location !33
+    %rbp = POP64r implicit-def %rsp, implicit %rsp, debug-location !33
+    TAILJMPd64 @sink, csr_64, implicit %rsp, implicit %rsp, implicit %edi, debug-location !33
+
+...
diff --git a/test/DebugInfo/X86/fission-ranges.ll b/test/DebugInfo/X86/fission-ranges.ll
index 3c05f223ee79..0dfb13ab66b7 100644
--- a/test/DebugInfo/X86/fission-ranges.ll
+++ b/test/DebugInfo/X86/fission-ranges.ll
@@ -32,13 +32,13 @@
 ; CHECK-NEXT:                    Length: 25
 ; CHECK-NEXT:      Location description: 50 93 04
 ; CHECK: [[E]]: Beginning address index: 4
-; CHECK-NEXT:                    Length: 23
+; CHECK-NEXT:                    Length: 19
 ; CHECK-NEXT:      Location description: 50 93 04
 ; CHECK: [[B]]: Beginning address index: 5
-; CHECK-NEXT:                    Length: 21
+; CHECK-NEXT:                    Length: 17
 ; CHECK-NEXT:      Location description: 50 93 04
 ; CHECK: [[D]]: Beginning address index: 6
-; CHECK-NEXT:                    Length: 21
+; CHECK-NEXT:                    Length: 17
 ; CHECK-NEXT:      Location description: 50 93 04
 
 ; Make sure we don't produce any relocations in any .dwo section (though in particular, debug_info.dwo)
-- 
2.7.4