[llvm] r351525 - [CodeGen] Fix bugs in LiveDebugVariables when debug labels are generated.
Hsiangkai Wang via llvm-commits
llvm-commits at lists.llvm.org
Thu Jan 17 23:17:10 PST 2019
Author: hsiangkai
Date: Thu Jan 17 23:17:09 2019
New Revision: 351525
URL: http://llvm.org/viewvc/llvm-project?rev=351525&view=rev
Log:
[CodeGen] Fix bugs in LiveDebugVariables when debug labels are generated.
Remove DBG_LABELs in LiveDebugVariables and generate them in
VirtRegRewriter.
This bug is reported in
https://bugs.chromium.org/p/chromium/issues/detail?id=898152.
Differential Revision: https://reviews.llvm.org/D54465
Added:
llvm/trunk/test/CodeGen/Generic/live-debug-label.ll
Modified:
llvm/trunk/lib/CodeGen/LiveDebugVariables.cpp
Modified: llvm/trunk/lib/CodeGen/LiveDebugVariables.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/LiveDebugVariables.cpp?rev=351525&r1=351524&r2=351525&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/LiveDebugVariables.cpp (original)
+++ llvm/trunk/lib/CodeGen/LiveDebugVariables.cpp Thu Jan 17 23:17:09 2019
@@ -71,6 +71,7 @@ EnableLDV("live-debug-variables", cl::in
cl::desc("Enable the live debug variables pass"), cl::Hidden);
STATISTIC(NumInsertedDebugValues, "Number of DBG_VALUEs inserted");
+STATISTIC(NumInsertedDebugLabels, "Number of DBG_LABELs inserted");
char LiveDebugVariables::ID = 0;
@@ -339,6 +340,37 @@ public:
void print(raw_ostream &, const TargetRegisterInfo *);
};
+/// A user label is a part of a debug info user label.
+class UserLabel {
+ const DILabel *Label; ///< The debug info label we are part of.
+ DebugLoc dl; ///< The debug location for the label. This is
+ ///< used by dwarf writer to find lexical scope.
+ SlotIndex loc; ///< Slot used by the debug label.
+
+ /// Insert a DBG_LABEL into MBB at Idx.
+ void insertDebugLabel(MachineBasicBlock *MBB, SlotIndex Idx,
+ LiveIntervals &LIS, const TargetInstrInfo &TII);
+
+public:
+ /// Create a new UserLabel.
+ UserLabel(const DILabel *label, DebugLoc L, SlotIndex Idx)
+ : Label(label), dl(std::move(L)), loc(Idx) {}
+
+ /// Does this UserLabel match the parameters?
+ bool match(const DILabel *L, const DILocation *IA,
+ const SlotIndex Index) const {
+ return Label == L && dl->getInlinedAt() == IA && loc == Index;
+ }
+
+ /// Recreate DBG_LABEL instruction from data structures.
+ void emitDebugLabel(LiveIntervals &LIS, const TargetInstrInfo &TII);
+
+ /// Return DebugLoc of this UserLabel.
+ DebugLoc getDebugLoc() { return dl; }
+
+ void print(raw_ostream &, const TargetRegisterInfo *);
+};
+
/// Implementation of the LiveDebugVariables pass.
class LDVImpl {
LiveDebugVariables &pass;
@@ -356,6 +388,9 @@ class LDVImpl {
/// All allocated UserValue instances.
SmallVector<std::unique_ptr<UserValue>, 8> userValues;
+ /// All allocated UserLabel instances.
+ SmallVector<std::unique_ptr<UserLabel>, 2> userLabels;
+
/// Map virtual register to eq class leader.
using VRMap = DenseMap<unsigned, UserValue *>;
VRMap virtRegToEqClass;
@@ -379,6 +414,14 @@ class LDVImpl {
/// \returns True if the DBG_VALUE instruction should be deleted.
bool handleDebugValue(MachineInstr &MI, SlotIndex Idx);
+ /// Add DBG_LABEL instruction to UserLabel.
+ ///
+ /// \param MI DBG_LABEL instruction
+ /// \param Idx Last valid SlotIndex before instruction.
+ ///
+ /// \returns True if the DBG_LABEL instruction should be deleted.
+ bool handleDebugLabel(MachineInstr &MI, SlotIndex Idx);
+
/// Collect and erase all DBG_VALUE instructions, adding a UserValue def
/// for each instruction.
///
@@ -400,6 +443,7 @@ public:
void clear() {
MF = nullptr;
userValues.clear();
+ userLabels.clear();
virtRegToEqClass.clear();
userVarMap.clear();
// Make sure we call emitDebugValues if the machine function was modified.
@@ -445,12 +489,21 @@ static void printDebugLoc(const DebugLoc
CommentOS << " ]";
}
-static void printExtendedName(raw_ostream &OS, const DILocalVariable *V,
+static void printExtendedName(raw_ostream &OS, const DINode *Node,
const DILocation *DL) {
- const LLVMContext &Ctx = V->getContext();
- StringRef Res = V->getName();
+ const LLVMContext &Ctx = Node->getContext();
+ StringRef Res;
+ unsigned Line;
+ if (const auto *V = dyn_cast<const DILocalVariable>(Node)) {
+ Res = V->getName();
+ Line = V->getLine();
+ } else if (const auto *L = dyn_cast<const DILabel>(Node)) {
+ Res = L->getName();
+ Line = L->getLine();
+ }
+
if (!Res.empty())
- OS << Res << "," << V->getLine();
+ OS << Res << "," << Line;
if (auto *InlinedAt = DL->getInlinedAt()) {
if (DebugLoc InlinedAtDL = InlinedAt) {
OS << " @[";
@@ -461,9 +514,8 @@ static void printExtendedName(raw_ostrea
}
void UserValue::print(raw_ostream &OS, const TargetRegisterInfo *TRI) {
- auto *DV = cast<DILocalVariable>(Variable);
OS << "!\"";
- printExtendedName(OS, DV, dl);
+ printExtendedName(OS, Variable, dl);
OS << "\"\t";
for (LocMap::const_iterator I = locInts.begin(); I.valid(); ++I) {
@@ -483,10 +535,22 @@ void UserValue::print(raw_ostream &OS, c
OS << '\n';
}
+void UserLabel::print(raw_ostream &OS, const TargetRegisterInfo *TRI) {
+ OS << "!\"";
+ printExtendedName(OS, Label, dl);
+
+ OS << "\"\t";
+ OS << loc;
+ OS << '\n';
+}
+
void LDVImpl::print(raw_ostream &OS) {
OS << "********** DEBUG VARIABLES **********\n";
- for (unsigned i = 0, e = userValues.size(); i != e; ++i)
- userValues[i]->print(OS, TRI);
+ for (auto &userValue : userValues)
+ userValue->print(OS, TRI);
+ OS << "********** DEBUG LABELS **********\n";
+ for (auto &userLabel : userLabels)
+ userLabel->print(OS, TRI);
}
#endif
@@ -587,6 +651,29 @@ bool LDVImpl::handleDebugValue(MachineIn
return true;
}
+bool LDVImpl::handleDebugLabel(MachineInstr &MI, SlotIndex Idx) {
+ // DBG_LABEL label
+ if (MI.getNumOperands() != 1 || !MI.getOperand(0).isMetadata()) {
+ LLVM_DEBUG(dbgs() << "Can't handle " << MI);
+ return false;
+ }
+
+ // Get or create the UserLabel for label here.
+ const DILabel *Label = MI.getDebugLabel();
+ const DebugLoc &DL = MI.getDebugLoc();
+ bool Found = false;
+ for (auto const &L : userLabels) {
+ if (L->match(Label, DL->getInlinedAt(), Idx)) {
+ Found = true;
+ break;
+ }
+ }
+ if (!Found)
+ userLabels.push_back(llvm::make_unique<UserLabel>(Label, DL, Idx));
+
+ return true;
+}
+
bool LDVImpl::collectDebugValues(MachineFunction &mf) {
bool Changed = false;
for (MachineFunction::iterator MFI = mf.begin(), MFE = mf.end(); MFI != MFE;
@@ -610,7 +697,8 @@ bool LDVImpl::collectDebugValues(Machine
do {
// Only handle DBG_VALUE in handleDebugValue(). Skip all other
// kinds of debug instructions.
- if (MBBI->isDebugValue() && handleDebugValue(*MBBI, Idx)) {
+ if ((MBBI->isDebugValue() && handleDebugValue(*MBBI, Idx)) ||
+ (MBBI->isDebugLabel() && handleDebugLabel(*MBBI, Idx))) {
MBBI = MBB->erase(MBBI);
Changed = true;
} else
@@ -1247,6 +1335,15 @@ void UserValue::insertDebugValue(Machine
} while (I != MBB->end());
}
+void UserLabel::insertDebugLabel(MachineBasicBlock *MBB, SlotIndex Idx,
+ LiveIntervals &LIS,
+ const TargetInstrInfo &TII) {
+ MachineBasicBlock::iterator I = findInsertLocation(MBB, Idx, LIS);
+ ++NumInsertedDebugLabels;
+ BuildMI(*MBB, I, getDebugLoc(), TII.get(TargetOpcode::DBG_LABEL))
+ .addMetadata(Label);
+}
+
void UserValue::emitDebugValues(VirtRegMap *VRM, LiveIntervals &LIS,
const TargetInstrInfo &TII,
const TargetRegisterInfo &TRI,
@@ -1295,16 +1392,31 @@ void UserValue::emitDebugValues(VirtRegM
}
}
+void UserLabel::emitDebugLabel(LiveIntervals &LIS, const TargetInstrInfo &TII) {
+ LLVM_DEBUG(dbgs() << "\t" << loc);
+ MachineFunction::iterator MBB = LIS.getMBBFromIndex(loc)->getIterator();
+
+ LLVM_DEBUG(dbgs() << ' ' << printMBBReference(*MBB));
+ insertDebugLabel(&*MBB, loc, LIS, TII);
+
+ LLVM_DEBUG(dbgs() << '\n');
+}
+
void LDVImpl::emitDebugValues(VirtRegMap *VRM) {
LLVM_DEBUG(dbgs() << "********** EMITTING LIVE DEBUG VARIABLES **********\n");
if (!MF)
return;
const TargetInstrInfo *TII = MF->getSubtarget().getInstrInfo();
SpillOffsetMap SpillOffsets;
- for (unsigned i = 0, e = userValues.size(); i != e; ++i) {
- LLVM_DEBUG(userValues[i]->print(dbgs(), TRI));
- userValues[i]->rewriteLocations(*VRM, *MF, *TII, *TRI, SpillOffsets);
- userValues[i]->emitDebugValues(VRM, *LIS, *TII, *TRI, SpillOffsets);
+ for (auto &userValue : userValues) {
+ LLVM_DEBUG(userValue->print(dbgs(), TRI));
+ userValue->rewriteLocations(*VRM, *MF, *TII, *TRI, SpillOffsets);
+ userValue->emitDebugValues(VRM, *LIS, *TII, *TRI, SpillOffsets);
+ }
+ LLVM_DEBUG(dbgs() << "********** EMITTING LIVE DEBUG LABELS **********\n");
+ for (auto &userLabel : userLabels) {
+ LLVM_DEBUG(userLabel->print(dbgs(), TRI));
+ userLabel->emitDebugLabel(*LIS, *TII);
}
EmitDone = true;
}
Added: llvm/trunk/test/CodeGen/Generic/live-debug-label.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/Generic/live-debug-label.ll?rev=351525&view=auto
==============================================================================
--- llvm/trunk/test/CodeGen/Generic/live-debug-label.ll (added)
+++ llvm/trunk/test/CodeGen/Generic/live-debug-label.ll Thu Jan 17 23:17:09 2019
@@ -0,0 +1,141 @@
+; RUN: llc < %s -stop-after=virtregrewriter -o - | FileCheck %s
+;
+; Generated with "clang++ -g -O1 -S -emit-llvm"
+;
+; inline bool bar(char c) {
+; return c >= '0' && c <= '9';
+; }
+;
+; unsigned foo(const char* data,
+; int length,
+; int* parsing_result) {
+; unsigned value = 0;
+; int result = 1;
+; bool overflow = 0;
+;
+; while (bar(*data)) {
+; if (value > 1) {
+; result = 2;
+; overflow = 1;
+; }
+;
+; if (!overflow)
+; value = value + 1;
+; }
+;
+; if (length == 0 || value) {
+; if (!overflow)
+; result = 0;
+; } else {
+; result = 1;
+; }
+; bye:
+; *parsing_result = result;
+; return result == 0 ? value : 0;
+; }
+;
+; CHECK: {{^body:}}
+; CHECK: bye.thread21:
+; CHECK: DBG_LABEL !14
+; CHECK: if.then5:
+; CHECK: DBG_LABEL !14
+; CHECK-NOT: DBG_LABEL !14
+
+$_Z3barc = comdat any
+
+; Function Attrs: nounwind uwtable
+define dso_local i32 @_Z3fooPKciPi(i8* nocapture readonly %data, i32 %length, i32* nocapture %parsing_result) local_unnamed_addr !dbg !4 {
+entry:
+ %0 = load i8, i8* %data, align 1
+ %call23 = tail call zeroext i1 @_Z3barc(i8 signext %0), !dbg !15
+ br i1 %call23, label %while.body, label %while.end
+
+while.body: ; preds = %entry, %while.body
+ %overflow.026 = phi i8 [ %spec.select18, %while.body ], [ 0, %entry ]
+ %result.025 = phi i32 [ %spec.select, %while.body ], [ 1, %entry ]
+ %value.024 = phi i32 [ %value.1, %while.body ], [ 0, %entry ]
+ %cmp = icmp ugt i32 %value.024, 1
+ %spec.select = select i1 %cmp, i32 2, i32 %result.025
+ %spec.select18 = select i1 %cmp, i8 1, i8 %overflow.026
+ %1 = and i8 %spec.select18, 1
+ %2 = xor i8 %1, 1
+ %3 = zext i8 %2 to i32
+ %value.1 = add i32 %value.024, %3
+ %4 = load i8, i8* %data, align 1
+ %call = tail call zeroext i1 @_Z3barc(i8 signext %4), !dbg !15
+ br i1 %call, label %while.body, label %while.end.loopexit
+
+while.end.loopexit: ; preds = %while.body
+ %phitmp = and i8 %spec.select18, 1
+ br label %while.end
+
+while.end: ; preds = %while.end.loopexit, %entry
+ %value.0.lcssa = phi i32 [ 0, %entry ], [ %value.1, %while.end.loopexit ]
+ %result.0.lcssa = phi i32 [ 1, %entry ], [ %spec.select, %while.end.loopexit ]
+ %overflow.0.lcssa = phi i8 [ 0, %entry ], [ %phitmp, %while.end.loopexit ]
+ %cmp3 = icmp eq i32 %length, 0
+ %tobool4 = icmp ne i32 %value.0.lcssa, 0
+ %or.cond = or i1 %cmp3, %tobool4
+ br i1 %or.cond, label %if.then5, label %bye.thread21
+
+bye.thread21: ; preds = %while.end
+ call void @llvm.dbg.label(metadata !14), !dbg !16
+ store i32 1, i32* %parsing_result, align 4
+ br label %6
+
+if.then5: ; preds = %while.end
+ %tobool6 = icmp eq i8 %overflow.0.lcssa, 0
+ call void @llvm.dbg.label(metadata !14), !dbg !16
+ call void @llvm.dbg.label(metadata !14), !dbg !16
+ br i1 %tobool6, label %bye.thread, label %bye
+
+bye.thread: ; preds = %if.then5
+ store i32 0, i32* %parsing_result, align 4
+ br label %5
+
+bye: ; preds = %if.then5
+ store i32 %result.0.lcssa, i32* %parsing_result, align 4
+ %cmp10 = icmp eq i32 %result.0.lcssa, 0
+ br i1 %cmp10, label %5, label %6
+
+; <label>:5: ; preds = %bye.thread, %bye
+ br label %6
+
+; <label>:6: ; preds = %bye.thread21, %bye, %5
+ %7 = phi i32 [ %value.0.lcssa, %5 ], [ 0, %bye ], [ 0, %bye.thread21 ]
+ ret i32 %7
+}
+
+; Function Attrs: inlinehint nounwind uwtable
+define linkonce_odr dso_local zeroext i1 @_Z3barc(i8 signext %c) local_unnamed_addr comdat {
+entry:
+ %c.off = add i8 %c, -48
+ %0 = icmp ult i8 %c.off, 10
+ ret i1 %0
+}
+
+; Function Attrs: nounwind readnone speculatable
+declare void @llvm.dbg.label(metadata) #0
+
+attributes #0 = { nounwind readnone speculatable }
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!3}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !1, isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, nameTableKind: None)
+!1 = !DIFile(filename: "live-debug-label.cc", directory: ".")
+!2 = !{}
+!3 = !{i32 2, !"Debug Info Version", i32 3}
+!4 = distinct !DISubprogram(name: "foo", linkageName: "_Z3fooPKciPi", scope: !1, file: !1, line: 5, type: !5, isLocal: false, isDefinition: true, scopeLine: 7, flags: DIFlagPrototyped, isOptimized: true, unit: !0, retainedNodes: !13)
+!5 = !DISubroutineType(types: !6)
+!6 = !{!7, !8, !11, !12}
+!7 = !DIBasicType(name: "unsigned int", size: 32, encoding: DW_ATE_unsigned)
+!8 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !9, size: 64)
+!9 = !DIDerivedType(tag: DW_TAG_const_type, baseType: !10)
+!10 = !DIBasicType(name: "char", size: 8, encoding: DW_ATE_signed_char)
+!11 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
+!12 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !11, size: 64)
+!13 = !{!14}
+!14 = !DILabel(scope: !4, name: "bye", file: !1, line: 28)
+!15 = !DILocation(line: 12, column: 10, scope: !4)
+!16 = !DILocation(line: 28, column: 1, scope: !4)
More information about the llvm-commits
mailing list