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Salinas, David
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[StructurizeCFG] Stop setting DebugLocs in flow blocks (llvm#139088) (llvm#2281)
2 parents 160ae96 + 8cb07ce commit 3a4a864

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-46
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3 files changed

+39
-46
lines changed

‎llvm/lib/Transforms/Scalar/StructurizeCFG.cpp‎

Lines changed: 22 additions & 29 deletions
Original file line numberDiff line numberDiff line change
@@ -129,8 +129,6 @@ using BBPredicates = DenseMap<BasicBlock *, PredInfo>;
129129
using PredMap = DenseMap<BasicBlock *, BBPredicates>;
130130
using BB2BBMap = DenseMap<BasicBlock *, BasicBlock *>;
131131

132-
using BranchDebugLocMap = DenseMap<BasicBlock *, DebugLoc>;
133-
134132
// A traits type that is intended to be used in graph algorithms. The graph
135133
// traits starts at an entry node, and traverses the RegionNodes that are in
136134
// the Nodes set.
@@ -303,8 +301,6 @@ class StructurizeCFG {
303301
PredMap LoopPreds;
304302
BranchVector LoopConds;
305303

306-
BranchDebugLocMap TermDL;
307-
308304
RegionNode *PrevNode;
309305

310306
void orderNodes();
@@ -336,14 +332,14 @@ class StructurizeCFG {
336332

337333
void simplifyAffectedPhis();
338334

339-
void killTerminator(BasicBlock *BB);
335+
DebugLoc killTerminator(BasicBlock *BB);
340336

341337
void changeExit(RegionNode *Node, BasicBlock *NewExit,
342338
bool IncludeDominator);
343339

344340
BasicBlock *getNextFlow(BasicBlock *Dominator);
345341

346-
BasicBlock *needPrefix(bool NeedEmpty);
342+
std::pair<BasicBlock *, DebugLoc> needPrefix(bool NeedEmpty);
347343

348344
BasicBlock *needPostfix(BasicBlock *Flow, bool ExitUseAllowed);
349345

@@ -595,14 +591,14 @@ void StructurizeCFG::collectInfos() {
595591
// Find the last back edges
596592
analyzeLoops(RN);
597593
}
598-
594+
/*
599595
// Reset the collected term debug locations
600596
TermDL.clear();
601597
602598
for (BasicBlock &BB : *Func) {
603599
if (const DebugLoc &DL = BB.getTerminator()->getDebugLoc())
604600
TermDL[&BB] = DL;
605-
}
601+
} */
606602
}
607603

608604
/// Insert the missing branch conditions
@@ -924,15 +920,17 @@ void StructurizeCFG::simplifyAffectedPhis() {
924920
}
925921

926922
/// Remove phi values from all successors and then remove the terminator.
927-
void StructurizeCFG::killTerminator(BasicBlock *BB) {
923+
DebugLoc StructurizeCFG::killTerminator(BasicBlock *BB) {
928924
Instruction *Term = BB->getTerminator();
929925
if (!Term)
930-
return;
926+
return DebugLoc();
931927

932928
for (BasicBlock *Succ : successors(BB))
933929
delPhiValues(BB, Succ);
934930

931+
DebugLoc DL = Term->getDebugLoc();
935932
Term->eraseFromParent();
933+
return DL;
936934
}
937935

938936
/// Let node exit(s) point to NewExit
@@ -971,9 +969,9 @@ void StructurizeCFG::changeExit(RegionNode *Node, BasicBlock *NewExit,
971969
SubRegion->replaceExit(NewExit);
972970
} else {
973971
BasicBlock *BB = Node->getNodeAs<BasicBlock>();
974-
killTerminator(BB);
972+
DebugLoc DL = killTerminator(BB);
975973
BranchInst *Br = BranchInst::Create(NewExit, BB);
976-
Br->setDebugLoc(TermDL[BB]);
974+
Br->setDebugLoc(DL);
977975
addPhiValues(BB, NewExit);
978976
if (IncludeDominator)
979977
DT->changeImmediateDominator(NewExit, BB);
@@ -988,25 +986,20 @@ BasicBlock *StructurizeCFG::getNextFlow(BasicBlock *Dominator) {
988986
BasicBlock *Flow = BasicBlock::Create(Context, FlowBlockName,
989987
Func, Insert);
990988
FlowSet.insert(Flow);
991-
992-
// use a temporary variable to avoid a use-after-free if the map's storage is
993-
// reallocated
994-
DebugLoc DL = TermDL[Dominator];
995-
TermDL[Flow] = std::move(DL);
996-
997989
DT->addNewBlock(Flow, Dominator);
998990
ParentRegion->getRegionInfo()->setRegionFor(Flow, ParentRegion);
999991
return Flow;
1000992
}
1001993

1002-
/// Create a new or reuse the previous node as flow node
1003-
BasicBlock *StructurizeCFG::needPrefix(bool NeedEmpty) {
994+
/// Create a new or reuse the previous node as flow node. Returns a block and a
995+
/// debug location to be used for new instructions in that block.
996+
std::pair<BasicBlock *, DebugLoc> StructurizeCFG::needPrefix(bool NeedEmpty) {
1004997
BasicBlock *Entry = PrevNode->getEntry();
1005998

1006999
if (!PrevNode->isSubRegion()) {
1007-
killTerminator(Entry);
1000+
DebugLoc DL = killTerminator(Entry);
10081001
if (!NeedEmpty || Entry->getFirstInsertionPt() == Entry->end())
1009-
return Entry;
1002+
return {Entry, DL};
10101003
}
10111004

10121005
// create a new flow node
@@ -1015,7 +1008,7 @@ BasicBlock *StructurizeCFG::needPrefix(bool NeedEmpty) {
10151008
// and wire it up
10161009
changeExit(PrevNode, Flow, true);
10171010
PrevNode = ParentRegion->getBBNode(Flow);
1018-
return Flow;
1011+
return {Flow, DebugLoc()};
10191012
}
10201013

10211014
/// Returns the region exit if possible, otherwise just a new flow node
@@ -1079,15 +1072,15 @@ void StructurizeCFG::wireFlow(bool ExitUseAllowed,
10791072
PrevNode = Node;
10801073
} else {
10811074
// Insert extra prefix node (or reuse last one)
1082-
BasicBlock *Flow = needPrefix(false);
1075+
auto [Flow, DL] = needPrefix(false);
10831076

10841077
// Insert extra postfix node (or use exit instead)
10851078
BasicBlock *Entry = Node->getEntry();
10861079
BasicBlock *Next = needPostfix(Flow, ExitUseAllowed);
10871080

10881081
// let it point to entry and next block
10891082
BranchInst *Br = BranchInst::Create(Entry, Next, BoolPoison, Flow);
1090-
Br->setDebugLoc(TermDL[Flow]);
1083+
Br->setDebugLoc(DL);
10911084
Conditions.push_back(Br);
10921085
addPhiValues(Flow, Entry);
10931086
DT->changeImmediateDominator(Entry, Flow);
@@ -1114,7 +1107,7 @@ void StructurizeCFG::handleLoops(bool ExitUseAllowed,
11141107
}
11151108

11161109
if (!isPredictableTrue(Node))
1117-
LoopStart = needPrefix(true);
1110+
LoopStart = needPrefix(true).first;
11181111

11191112
LoopEnd = Loops[Node->getEntry()];
11201113
wireFlow(false, LoopEnd);
@@ -1125,10 +1118,11 @@ void StructurizeCFG::handleLoops(bool ExitUseAllowed,
11251118
assert(LoopStart != &LoopStart->getParent()->getEntryBlock());
11261119

11271120
// Create an extra loop end node
1128-
LoopEnd = needPrefix(false);
1121+
DebugLoc DL;
1122+
std::tie(LoopEnd, DL) = needPrefix(false);
11291123
BasicBlock *Next = needPostfix(LoopEnd, ExitUseAllowed);
11301124
BranchInst *Br = BranchInst::Create(Next, LoopStart, BoolPoison, LoopEnd);
1131-
Br->setDebugLoc(TermDL[LoopEnd]);
1125+
Br->setDebugLoc(DL);
11321126
LoopConds.push_back(Br);
11331127
addPhiValues(LoopEnd, LoopStart);
11341128
setPrevNode(Next);
@@ -1328,7 +1322,6 @@ bool StructurizeCFG::run(Region *R, DominatorTree *DT) {
13281322
LoopPreds.clear();
13291323
LoopConds.clear();
13301324
FlowSet.clear();
1331-
TermDL.clear();
13321325

13331326
return true;
13341327
}

‎llvm/test/CodeGen/AMDGPU/si-annotate-dbg-info.ll‎

Lines changed: 9 additions & 9 deletions
Original file line numberDiff line numberDiff line change
@@ -12,17 +12,17 @@ define amdgpu_ps i32 @if_else(i32 %0) !dbg !5 {
1212
; OPT-NEXT: [[TMP4:%.*]] = extractvalue { i1, i64 } [[TMP2]], 1, !dbg [[DBG14]]
1313
; OPT-NEXT: br i1 [[TMP3]], label [[FALSE:%.*]], label [[FLOW:%.*]], !dbg [[DBG14]]
1414
; OPT: Flow:
15-
; OPT-NEXT: [[TMP5:%.*]] = phi i32 [ 33, [[FALSE]] ], [ undef, [[TMP1:%.*]] ]
16-
; OPT-NEXT: [[TMP6:%.*]] = call { i1, i64 } @llvm.amdgcn.else.i64.i64(i64 [[TMP4]]), !dbg [[DBG14]]
17-
; OPT-NEXT: [[TMP7:%.*]] = extractvalue { i1, i64 } [[TMP6]], 0, !dbg [[DBG14]]
18-
; OPT-NEXT: [[TMP8:%.*]] = extractvalue { i1, i64 } [[TMP6]], 1, !dbg [[DBG14]]
19-
; OPT-NEXT: br i1 [[TMP7]], label [[TRUE:%.*]], label [[EXIT:%.*]], !dbg [[DBG14]]
15+
; OPT-NEXT: [[TMP7:%.*]] = phi i32 [ 33, [[FALSE]] ], [ undef, [[TMP1:%.*]] ]
16+
; OPT-NEXT: [[TMP5:%.*]] = call { i1, i64 } @llvm.amdgcn.else.i64.i64(i64 [[TMP4]])
17+
; OPT-NEXT: [[TMP6:%.*]] = extractvalue { i1, i64 } [[TMP5]], 0
18+
; OPT-NEXT: [[TMP8:%.*]] = extractvalue { i1, i64 } [[TMP5]], 1
19+
; OPT-NEXT: br i1 [[TMP6]], label [[TRUE:%.*]], label [[EXIT:%.*]]
2020
; OPT: true:
2121
; OPT-NEXT: br label [[EXIT]], !dbg [[DBG15:![0-9]+]]
2222
; OPT: false:
2323
; OPT-NEXT: br label [[FLOW]], !dbg [[DBG16:![0-9]+]]
2424
; OPT: exit:
25-
; OPT-NEXT: [[RET:%.*]] = phi i32 [ [[TMP5]], [[FLOW]] ], [ 42, [[TRUE]] ], !dbg [[DBG17:![0-9]+]]
25+
; OPT-NEXT: [[RET:%.*]] = phi i32 [ [[TMP7]], [[FLOW]] ], [ 42, [[TRUE]] ], !dbg [[DBG17:![0-9]+]]
2626
; OPT-NEXT: call void @llvm.amdgcn.end.cf.i64(i64 [[TMP8]])
2727
; OPT-NEXT: #dbg_value(i32 [[RET]], [[META11:![0-9]+]], !DIExpression(), [[DBG17]])
2828
; OPT-NEXT: ret i32 [[RET]], !dbg [[DBG18:![0-9]+]]
@@ -66,9 +66,9 @@ define amdgpu_ps void @loop_if_break(i32 %n) !dbg !19 {
6666
; OPT-NEXT: [[TMP3]] = phi i32 [ [[I_NEXT]], [[LOOP_BODY]] ], [ undef, [[LOOP]] ]
6767
; OPT-NEXT: [[TMP4:%.*]] = phi i1 [ false, [[LOOP_BODY]] ], [ true, [[LOOP]] ]
6868
; OPT-NEXT: call void @llvm.amdgcn.end.cf.i64(i64 [[TMP2]])
69-
; OPT-NEXT: [[TMP5]] = call i64 @llvm.amdgcn.if.break.i64(i1 [[TMP4]], i64 [[PHI_BROKEN]]), !dbg [[DBG27]]
70-
; OPT-NEXT: [[TMP6:%.*]] = call i1 @llvm.amdgcn.loop.i64(i64 [[TMP5]]), !dbg [[DBG27]]
71-
; OPT-NEXT: br i1 [[TMP6]], label [[EXIT:%.*]], label [[LOOP]], !dbg [[DBG27]]
69+
; OPT-NEXT: [[TMP5]] = call i64 @llvm.amdgcn.if.break.i64(i1 [[TMP4]], i64 [[PHI_BROKEN]])
70+
; OPT-NEXT: [[TMP6:%.*]] = call i1 @llvm.amdgcn.loop.i64(i64 [[TMP5]])
71+
; OPT-NEXT: br i1 [[TMP6]], label [[EXIT:%.*]], label [[LOOP]]
7272
; OPT: exit:
7373
; OPT-NEXT: call void @llvm.amdgcn.end.cf.i64(i64 [[TMP5]])
7474
; OPT-NEXT: ret void, !dbg [[DBG30:![0-9]+]]

‎llvm/test/Transforms/StructurizeCFG/structurizecfg-debug-loc.ll‎

Lines changed: 8 additions & 8 deletions
Original file line numberDiff line numberDiff line change
@@ -5,7 +5,7 @@ define void @if_then_else(ptr addrspace(1) %out, i1 %arg) !dbg !7 {
55
; CHECK: entry:
66
; CHECK: br i1 {{.*}}, label %if.else, label %Flow, !dbg [[ITE_ENTRY_DL:![0-9]+]]
77
; CHECK: Flow:
8-
; CHECK: br i1 {{.*}}, label %if.then, label %exit, !dbg [[ITE_ENTRY_DL]]
8+
; CHECK: br i1 {{.*}}, label %if.then, label %exit
99
; CHECK: if.then:
1010
; CHECK: br label %exit, !dbg [[ITE_IFTHEN_DL:![0-9]+]]
1111
; CHECK: if.else:
@@ -36,7 +36,7 @@ define void @while_loop(ptr addrspace(1) %out) !dbg !14 {
3636
; CHECK: while.body:
3737
; CHECK: br label %Flow, !dbg [[WHILE_BODY_DL:![0-9]+]]
3838
; CHECK: Flow:
39-
; CHECK: br i1 {{.*}}, label %exit, label %while.header, !dbg [[WHILE_HEADER_DL]]
39+
; CHECK: br i1 {{.*}}, label %exit, label %while.header
4040
; CHECK: exit:
4141
;
4242
entry:
@@ -63,7 +63,7 @@ define void @while_multiple_exits(ptr addrspace(1) %out) !dbg !21 {
6363
; CHECK: while.exiting:
6464
; CHECK: br label %Flow, !dbg [[WHILEME_EXITING_DL:![0-9]+]]
6565
; CHECK: Flow:
66-
; CHECK: br i1 {{.*}}, label %exit, label %while.header, !dbg [[WHILEME_HEADER_DL]]
66+
; CHECK: br i1 {{.*}}, label %exit, label %while.header
6767
; CHECK: exit:
6868
;
6969
entry:
@@ -86,27 +86,27 @@ define void @nested_if_then_else(ptr addrspace(1) %out, i1 %a, i1 %b) !dbg !28 {
8686
; CHECK: entry:
8787
; CHECK: br i1 {{.*}}, label %if.else, label %Flow4, !dbg [[NESTED_ENTRY_DL:![0-9]+]]
8888
; CHECK: Flow4:
89-
; CHECK: br i1 {{.*}}, label %if.then, label %exit, !dbg [[NESTED_ENTRY_DL]]
89+
; CHECK: br i1 {{.*}}, label %if.then, label %exit
9090
; CHECK: if.then:
9191
; CHECK: br i1 {{.*}}, label %if.then.else, label %Flow2, !dbg [[NESTED_IFTHEN_DL:![0-9]+]]
9292
; CHECK: Flow2:
93-
; CHECK: br i1 {{.*}}, label %if.then.then, label %Flow3, !dbg [[NESTED_IFTHEN_DL]]
93+
; CHECK: br i1 {{.*}}, label %if.then.then, label %Flow3
9494
; CHECK: if.then.then:
9595
; CHECK: br label %Flow3, !dbg [[NESTED_IFTHENTHEN_DL:![0-9]+]]
9696
; CHECK: if.then.else:
9797
; CHECK: br label %Flow2, !dbg [[NESTED_IFTHENELSE_DL:![0-9]+]]
9898
; CHECK: if.else:
9999
; CHECK: br i1 {{.*}}, label %if.else.else, label %Flow, !dbg [[NESTED_IFELSE_DL:![0-9]+]]
100100
; CHECK: Flow:
101-
; CHECK: br i1 {{.*}}, label %if.else.then, label %Flow1, !dbg [[NESTED_IFELSE_DL]]
101+
; CHECK: br i1 {{.*}}, label %if.else.then, label %Flow1
102102
; CHECK: if.else.then:
103103
; CHECK: br label %Flow1, !dbg [[NESTED_IFELSETHEN_DL:![0-9]+]]
104104
; CHECK: if.else.else:
105105
; CHECK: br label %Flow, !dbg [[NESTED_IFELSEELSE_DL:![0-9]+]]
106106
; CHECK: Flow1:
107-
; CHECK: br label %Flow4, !dbg [[NESTED_IFELSE_DL]]
107+
; CHECK: br label %Flow4
108108
; CHECK: Flow3:
109-
; CHECK: br label %exit, !dbg [[NESTED_IFTHEN_DL]]
109+
; CHECK: br label %exit
110110
; CHECK: exit:
111111
;
112112
entry:

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