Index: llvm/lib/CodeGen/LiveDebugValues.cpp
===================================================================
--- llvm/lib/CodeGen/LiveDebugValues.cpp
+++ llvm/lib/CodeGen/LiveDebugValues.cpp
@@ -89,6 +89,23 @@
return MI.getOperand(0).isReg() ? MI.getOperand(0).getReg() : Register();
}
+// If @Op is a stack or frame register return true, otherwise return false. This
+// is used to avoid the debug entry values from the registers, since we do not
+// support it at the moment.
+static bool isRegOtherThanSPAndFP(const MachineOperand &Op, MachineInstr &MI,
+ const TargetRegisterInfo *TRI) {
+ if (!Op.isReg())
+ return false;
+
+ MachineFunction *MF = MI.getParent()->getParent();
+ const TargetLowering *TLI = MF->getSubtarget().getTargetLowering();
+ unsigned SP = TLI->getStackPointerRegisterToSaveRestore();
+ Register FP = TRI->getFrameRegister(*MF);
+ Register Reg = Op.getReg();
+
+ return Reg && Reg != SP && Reg != FP;
+}
+
namespace {
class LiveDebugValues : public MachineFunctionPass {
@@ -205,7 +222,9 @@
RegisterKind,
SpillLocKind,
ImmediateKind,
- EntryValueKind
+ EntryValueKind,
+ EntryValueBackupKind,
+ EntryValueCopyBackupKind
} Kind = InvalidKind;
/// The value location. Stored separately to avoid repeatedly
@@ -227,7 +246,7 @@
assert(MI.isDebugValue() && "not a DBG_VALUE");
assert(MI.getNumOperands() == 4 && "malformed DBG_VALUE");
if (int RegNo = isDbgValueDescribedByReg(MI)) {
- Kind = MI.isDebugEntryValue() ? EntryValueKind : RegisterKind;
+ Kind = RegisterKind;
Loc.RegNo = RegNo;
} else if (MI.getOperand(0).isImm()) {
Kind = ImmediateKind;
@@ -239,17 +258,50 @@
Kind = ImmediateKind;
Loc.CImm = MI.getOperand(0).getCImm();
}
- assert((Kind != ImmediateKind || !MI.isDebugEntryValue()) &&
- "entry values must be register locations");
+
+ // We create the debug entry values from the factory functions rather than
+ // from this ctor.
+ assert(Kind != EntryValueKind && !isEntryBackupLoc());
}
/// Take the variable and machine-location in DBG_VALUE MI, and build an
/// entry location using the given expression.
static VarLoc CreateEntryLoc(const MachineInstr &MI, LexicalScopes &LS,
- const DIExpression *EntryExpr) {
+ const DIExpression *EntryExpr, unsigned Reg) {
VarLoc VL(MI, LS);
+ assert(VL.Kind == RegisterKind);
VL.Kind = EntryValueKind;
VL.Expr = EntryExpr;
+ VL.Loc.RegNo = Reg;
+ return VL;
+ }
+
+ /// Take the variable and machine-location from the DBG_VALUE (from the
+ /// function entry), and build an entry value backup location. The backup
+ /// location will turn into the normal location if the backup is valid at
+ /// the time of the primary location clobbering.
+ static VarLoc CreateEntryBackupLoc(const MachineInstr &MI,
+ LexicalScopes &LS,
+ const DIExpression *EntryExpr) {
+ VarLoc VL(MI, LS);
+ assert(VL.Kind == RegisterKind);
+ VL.Kind = EntryValueBackupKind;
+ VL.Expr = EntryExpr;
+ return VL;
+ }
+
+ /// Take the variable and machine-location from the DBG_VALUE (from the
+ /// function entry), and build a copy of an entry value backup location by
+ /// setting the register location to NewReg.
+ static VarLoc CreateEntryCopyBackupLoc(const MachineInstr &MI,
+ LexicalScopes &LS,
+ const DIExpression *EntryExpr,
+ unsigned NewReg) {
+ VarLoc VL(MI, LS);
+ assert(VL.Kind == RegisterKind);
+ VL.Kind = EntryValueCopyBackupKind;
+ VL.Expr = EntryExpr;
+ VL.Loc.RegNo = NewReg;
return VL;
}
@@ -288,8 +340,11 @@
switch (Kind) {
case EntryValueKind:
// An entry value is a register location -- but with an updated
- // expression.
- return BuildMI(MF, DbgLoc, IID, Indirect, Loc.RegNo, Var, Expr);
+ // expression. The register location of such DBG_VALUE is always the one
+ // from the entry DBG_VALUE, it does not matter if the entry value was
+ // copied in to another register due to some optimizations.
+ return BuildMI(MF, DbgLoc, IID, Indirect, MI.getOperand(0).getReg(),
+ Var, Expr);
case RegisterKind:
// Register locations are like the source DBG_VALUE, but with the
// register number from this VarLoc.
@@ -308,8 +363,11 @@
MachineOperand MO = MI.getOperand(0);
return BuildMI(MF, DbgLoc, IID, Indirect, MO, Var, DIExpr);
}
+ case EntryValueBackupKind:
+ case EntryValueCopyBackupKind:
case InvalidKind:
- llvm_unreachable("Tried to produce DBG_VALUE for invalid VarLoc");
+ llvm_unreachable(
+ "Tried to produce DBG_VALUE for invalid or backup VarLoc");
}
llvm_unreachable("Unrecognized LiveDebugValues.VarLoc.Kind enum");
}
@@ -317,6 +375,27 @@
/// Is the Loc field a constant or constant object?
bool isConstant() const { return Kind == ImmediateKind; }
+ /// Check if the Loc field is an entry backup location.
+ bool isEntryBackupLoc() const {
+ return Kind == EntryValueBackupKind || Kind == EntryValueCopyBackupKind;
+ }
+
+ /// If this variable is described by a register holding the entry value,
+ /// return it, otherwise return 0.
+ unsigned getEntryValueBackupReg() const {
+ if (Kind == EntryValueBackupKind)
+ return Loc.RegNo;
+ return 0;
+ }
+
+ /// If this variable is described by a register holding the copy of the
+ /// entry value, return it, otherwise return 0.
+ unsigned getEntryValueCopyBackupReg() const {
+ if (Kind == EntryValueCopyBackupKind)
+ return Loc.RegNo;
+ return 0;
+ }
+
/// If this variable is described by a register, return it,
/// otherwise return 0.
unsigned isDescribedByReg() const {
@@ -336,6 +415,8 @@
switch (Kind) {
case RegisterKind:
case EntryValueKind:
+ case EntryValueBackupKind:
+ case EntryValueCopyBackupKind:
dbgs() << printReg(Loc.RegNo, TRI);
break;
case SpillLocKind:
@@ -353,7 +434,12 @@
if (Var.getInlinedAt())
dbgs() << "!" << Var.getInlinedAt()->getMetadataID() << ")\n";
else
- dbgs() << "(null))\n";
+ dbgs() << "(null))";
+
+ if (isEntryBackupLoc())
+ dbgs() << " (backup loc)\n";
+ else
+ dbgs() << "\n";
}
#endif
@@ -369,7 +455,6 @@
}
};
- using DebugParamMap = SmallDenseMap<const DILocalVariable *, MachineInstr *>;
using VarLocMap = UniqueVector<VarLoc>;
using VarLocSet = SparseBitVector<>;
using VarLocInMBB = SmallDenseMap<const MachineBasicBlock *, VarLocSet>;
@@ -399,6 +484,7 @@
class OpenRangesSet {
VarLocSet VarLocs;
SmallDenseMap<DebugVariable, unsigned, 8> Vars;
+ SmallDenseMap<DebugVariable, unsigned, 8> EntryValuesBackupVars;
OverlapMap &OverlappingFragments;
public:
@@ -406,40 +492,38 @@
const VarLocSet &getVarLocs() const { return VarLocs; }
- /// Terminate all open ranges for Var by removing it from the set.
- void erase(DebugVariable Var);
+ /// Terminate all open ranges for VL.Var by removing it from the set.
+ void erase(const VarLoc &VL);
/// Terminate all open ranges listed in \c KillSet by removing
/// them from the set.
- void erase(const VarLocSet &KillSet, const VarLocMap &VarLocIDs) {
- VarLocs.intersectWithComplement(KillSet);
- for (unsigned ID : KillSet)
- Vars.erase(VarLocIDs[ID].Var);
- }
+ void erase(const VarLocSet &KillSet, const VarLocMap &VarLocIDs);
/// Insert a new range into the set.
- void insert(unsigned VarLocID, DebugVariable Var) {
- VarLocs.set(VarLocID);
- Vars.insert({Var, VarLocID});
- }
+ void insert(unsigned VarLocID, const VarLoc &VL);
/// Insert a set of ranges.
void insertFromLocSet(const VarLocSet &ToLoad, const VarLocMap &Map) {
for (unsigned Id : ToLoad) {
- const VarLoc &Var = Map[Id];
- insert(Id, Var.Var);
+ const VarLoc &VarL = Map[Id];
+ insert(Id, VarL);
}
}
+ unsigned getEntryValueBackup(DebugVariable Var);
+
/// Empty the set.
void clear() {
VarLocs.clear();
Vars.clear();
+ EntryValuesBackupVars.clear();
}
/// Return whether the set is empty or not.
bool empty() const {
- assert(Vars.empty() == VarLocs.empty() && "open ranges are inconsistent");
+ assert((Vars.empty() && EntryValuesBackupVars.empty()) ==
+ VarLocs.empty() &&
+ "open ranges are inconsistent");
return VarLocs.empty();
}
};
@@ -473,21 +557,22 @@
VarLocMap &VarLocIDs);
void transferSpillOrRestoreInst(MachineInstr &MI, OpenRangesSet &OpenRanges,
VarLocMap &VarLocIDs, TransferMap &Transfers);
+ bool removeEntryValue(const MachineInstr &MI, OpenRangesSet &OpenRanges,
+ VarLocMap &VarLocIDs, const VarLoc &EntryVL);
void emitEntryValues(MachineInstr &MI, OpenRangesSet &OpenRanges,
VarLocMap &VarLocIDs, TransferMap &Transfers,
- DebugParamMap &DebugEntryVals,
SparseBitVector<> &KillSet);
+ void recordEntryValues(MachineInstr &MI, OpenRangesSet &OpenRanges,
+ VarLocMap &VarLocIDs);
void transferRegisterCopy(MachineInstr &MI, OpenRangesSet &OpenRanges,
VarLocMap &VarLocIDs, TransferMap &Transfers);
void transferRegisterDef(MachineInstr &MI, OpenRangesSet &OpenRanges,
- VarLocMap &VarLocIDs, TransferMap &Transfers,
- DebugParamMap &DebugEntryVals);
+ VarLocMap &VarLocIDs, TransferMap &Transfers);
bool transferTerminator(MachineBasicBlock *MBB, OpenRangesSet &OpenRanges,
VarLocInMBB &OutLocs, const VarLocMap &VarLocIDs);
void process(MachineInstr &MI, OpenRangesSet &OpenRanges,
- VarLocMap &VarLocIDs, TransferMap &Transfers,
- DebugParamMap &DebugEntryVals);
+ VarLocMap &VarLocIDs, TransferMap &Transfers);
void accumulateFragmentMap(MachineInstr &MI, VarToFragments &SeenFragments,
OverlapMap &OLapMap);
@@ -591,17 +676,20 @@
/// Erase a variable from the set of open ranges, and additionally erase any
/// fragments that may overlap it.
-void LiveDebugValues::OpenRangesSet::erase(DebugVariable Var) {
+void LiveDebugValues::OpenRangesSet::erase(const VarLoc &VL) {
// Erasure helper.
- auto DoErase = [this](DebugVariable VarToErase) {
- auto It = Vars.find(VarToErase);
- if (It != Vars.end()) {
+ auto DoErase = [VL, this](DebugVariable VarToErase) {
+ auto *EraseFrom = VL.isEntryBackupLoc() ? &EntryValuesBackupVars : &Vars;
+ auto It = EraseFrom->find(VarToErase);
+ if (It != EraseFrom->end()) {
unsigned ID = It->second;
VarLocs.reset(ID);
- Vars.erase(It);
+ EraseFrom->erase(It);
}
};
+ DebugVariable Var = VL.Var;
+
// Erase the variable/fragment that ends here.
DoErase(Var);
@@ -622,6 +710,34 @@
}
}
+void LiveDebugValues::OpenRangesSet::erase(const VarLocSet &KillSet,
+ const VarLocMap &VarLocIDs) {
+ VarLocs.intersectWithComplement(KillSet);
+ for (unsigned ID : KillSet) {
+ const VarLoc *VL = &VarLocIDs[ID];
+ auto *EraseFrom = VL->isEntryBackupLoc() ? &EntryValuesBackupVars : &Vars;
+ EraseFrom->erase(VL->Var);
+ }
+}
+
+void LiveDebugValues::OpenRangesSet::insert(unsigned VarLocID,
+ const VarLoc &VL) {
+ auto *InsertInto = VL.isEntryBackupLoc() ? &EntryValuesBackupVars : &Vars;
+ VarLocs.set(VarLocID);
+ InsertInto->insert({VL.Var, VarLocID});
+}
+
+/// Return the Loc ID of an entry value backup location, if it exists for the
+/// variable, otherwise return 0.
+unsigned
+LiveDebugValues::OpenRangesSet::getEntryValueBackup(DebugVariable Var) {
+ auto It = EntryValuesBackupVars.find(Var);
+ if (It != EntryValuesBackupVars.end())
+ return It->second;
+
+ return 0;
+}
+
//===----------------------------------------------------------------------===//
// Debug Range Extension Implementation
//===----------------------------------------------------------------------===//
@@ -664,6 +780,58 @@
return {Reg, Offset};
}
+/// Try to salvage the debug entry value if we encounter a new debug value
+/// describing the same parameter, otherwise stop tracking the value. Return
+/// true if we should stop tracking the entry value, otherwise return false.
+bool LiveDebugValues::removeEntryValue(const MachineInstr &MI,
+ OpenRangesSet &OpenRanges,
+ VarLocMap &VarLocIDs,
+ const VarLoc &EntryVL) {
+ // Skip the DBG_VALUE which is the debug entry value itself.
+ if (MI.isIdenticalTo(EntryVL.MI))
+ return false;
+
+ // If the parameter's location is not register location, we can not track
+ // the entry value any more. In addition, if the debug expression from the
+ // DBG_VALUE is not empty, we can assume the parameter's value has changed
+ // indicating that we should stop tracking its entry value as well.
+ if (!MI.getOperand(0).isReg() ||
+ MI.getDebugExpression()->getNumElements() != 0)
+ return true;
+
+ // If the DBG_VALUE comes from a copy instruction that copies the entry value,
+ // it means the parameter's value has not changed and we should be able to use
+ // its entry value.
+ bool TrySalvageEntryValue = false;
+ Register Reg = MI.getOperand(0).getReg();
+ const MachineOperand *SrcRegOp, *DestRegOp;
+ auto I = std::next(MI.getReverseIterator());
+ if (I == MI.getParent()->rend() || I->isDebugInstr()) {
+ // This is a propagated DBG_VALUE.
+ return false;
+ } else {
+ if (TII->isCopyInstr(*I, SrcRegOp, DestRegOp)) {
+ if (Reg != DestRegOp->getReg())
+ return true;
+ TrySalvageEntryValue = true;
+ }
+ }
+
+ if (TrySalvageEntryValue) {
+ for (unsigned ID : OpenRanges.getVarLocs()) {
+ const VarLoc &VL = VarLocIDs[ID];
+ if (!VL.isEntryBackupLoc())
+ continue;
+
+ if (VL.getEntryValueCopyBackupReg() == Reg &&
+ VL.MI.getOperand(0).getReg() == SrcRegOp->getReg())
+ return false;
+ }
+ }
+
+ return true;
+}
+
/// End all previous ranges related to @MI and start a new range from @MI
/// if it is a DBG_VALUE instr.
void LiveDebugValues::transferDebugValue(const MachineInstr &MI,
@@ -678,18 +846,33 @@
assert(Var->isValidLocationForIntrinsic(DebugLoc) &&
"Expected inlined-at fields to agree");
- // End all previous ranges of Var.
DebugVariable V(Var, Expr, InlinedAt);
- OpenRanges.erase(V);
- // Add the VarLoc to OpenRanges from this DBG_VALUE.
+ // Check if this DBG_VALUE indicates a parameter's value changing.
+ // If that is the case, we should stop tracking its entry value.
+ unsigned EntryValBackupID = OpenRanges.getEntryValueBackup(V);
+ if (Var->isParameter() && EntryValBackupID) {
+ const VarLoc &EntryVL = VarLocIDs[EntryValBackupID];
+ if (removeEntryValue(MI, OpenRanges, VarLocIDs, EntryVL)) {
+ LLVM_DEBUG(dbgs() << "Deleting a DBG entry value because of: ";
+ MI.print(dbgs(), /*IsStandalone*/ false,
+ /*SkipOpers*/ false, /*SkipDebugLoc*/ false,
+ /*AddNewLine*/ true, TII));
+ OpenRanges.erase(EntryVL);
+ }
+ }
+
unsigned ID;
if (isDbgValueDescribedByReg(MI) || MI.getOperand(0).isImm() ||
MI.getOperand(0).isFPImm() || MI.getOperand(0).isCImm()) {
// Use normal VarLoc constructor for registers and immediates.
VarLoc VL(MI, LS);
+ // End all previous ranges of VL.Var.
+ OpenRanges.erase(VL);
+
ID = VarLocIDs.insert(VL);
- OpenRanges.insert(ID, VL.Var);
+ // Add the VarLoc to OpenRanges from this DBG_VALUE.
+ OpenRanges.insert(ID, VL);
} else if (MI.hasOneMemOperand()) {
llvm_unreachable("DBG_VALUE with mem operand encountered after regalloc?");
} else {
@@ -699,32 +882,30 @@
}
}
+/// Turn the entry value backup locations into primary locations.
void LiveDebugValues::emitEntryValues(MachineInstr &MI,
OpenRangesSet &OpenRanges,
VarLocMap &VarLocIDs,
TransferMap &Transfers,
- DebugParamMap &DebugEntryVals,
SparseBitVector<> &KillSet) {
for (unsigned ID : KillSet) {
if (!VarLocIDs[ID].Var.getVar()->isParameter())
continue;
- const MachineInstr *CurrDebugInstr = &VarLocIDs[ID].MI;
+ auto DebugVar = VarLocIDs[ID].Var;
+ unsigned EntryValBackupID = OpenRanges.getEntryValueBackup(DebugVar);
- // If parameter's DBG_VALUE is not in the map that means we can't
- // generate parameter's entry value.
- if (!DebugEntryVals.count(CurrDebugInstr->getDebugVariable()))
+ // If the parameter has the entry value backup, it means we should
+ // be able to use its entry value.
+ if (!EntryValBackupID)
continue;
- auto ParamDebugInstr = DebugEntryVals[CurrDebugInstr->getDebugVariable()];
- DIExpression *NewExpr = DIExpression::prepend(
- ParamDebugInstr->getDebugExpression(), DIExpression::EntryValue);
-
- VarLoc EntryLoc = VarLoc::CreateEntryLoc(*ParamDebugInstr, LS, NewExpr);
-
- unsigned EntryValLocID = VarLocIDs.insert(EntryLoc);
- Transfers.push_back({&MI, EntryValLocID});
- OpenRanges.insert(EntryValLocID, EntryLoc.Var);
+ const VarLoc &EntryVL = VarLocIDs[EntryValBackupID];
+ VarLoc EntryLoc =
+ VarLoc::CreateEntryLoc(EntryVL.MI, LS, EntryVL.Expr, EntryVL.Loc.RegNo);
+ unsigned EntryValueID = VarLocIDs.insert(EntryLoc);
+ Transfers.push_back({&MI, EntryValueID});
+ OpenRanges.insert(EntryValueID, EntryLoc);
}
}
@@ -745,17 +926,17 @@
// Close this variable's previous location range.
DebugVariable V(*DebugInstr);
- OpenRanges.erase(V);
+ OpenRanges.erase(VL);
// Record the new location as an open range, and a postponed transfer
// inserting a DBG_VALUE for this location.
- OpenRanges.insert(LocId, VL.Var);
+ OpenRanges.insert(LocId, VL);
TransferDebugPair MIP = {&MI, LocId};
Transfers.push_back(MIP);
};
- // End all previous ranges of Var.
- OpenRanges.erase(VarLocIDs[OldVarID].Var);
+ // End all previous ranges of VL.Var.
+ OpenRanges.erase(VarLocIDs[OldVarID]);
switch (Kind) {
case TransferKind::TransferCopy: {
assert(NewReg &&
@@ -803,7 +984,7 @@
/// A definition of a register may mark the end of a range.
void LiveDebugValues::transferRegisterDef(
MachineInstr &MI, OpenRangesSet &OpenRanges, VarLocMap &VarLocIDs,
- TransferMap &Transfers, DebugParamMap &DebugEntryVals) {
+ TransferMap &Transfers) {
MachineFunction *MF = MI.getMF();
const TargetLowering *TLI = MF->getSubtarget().getTargetLowering();
unsigned SP = TLI->getStackPointerRegisterToSaveRestore();
@@ -837,8 +1018,7 @@
if (auto *TPC = getAnalysisIfAvailable<TargetPassConfig>()) {
auto &TM = TPC->getTM<TargetMachine>();
if (TM.Options.EnableDebugEntryValues)
- emitEntryValues(MI, OpenRanges, VarLocIDs, Transfers, DebugEntryVals,
- KillSet);
+ emitEntryValues(MI, OpenRanges, VarLocIDs, Transfers, KillSet);
}
}
@@ -999,8 +1179,10 @@
TransferMap &Transfers) {
const MachineOperand *SrcRegOp, *DestRegOp;
- if (!TII->isCopyInstr(MI, SrcRegOp, DestRegOp) || !SrcRegOp->isKill() ||
- !DestRegOp->isDef())
+ if (!TII->isCopyInstr(MI, SrcRegOp, DestRegOp))
+ return;
+
+ if (!DestRegOp->isDef())
return;
auto isCalleeSavedReg = [&](unsigned Reg) {
@@ -1021,6 +1203,30 @@
if (!isCalleeSavedReg(DestReg))
return;
+ // Remember an entry value movement. If we encounter a new debug value of
+ // a parameter describing only a moving of the value around, rather then
+ // modifying it, we are still able to use the entry value if needed.
+ if (isRegOtherThanSPAndFP(*DestRegOp, MI, TRI)) {
+ for (unsigned ID : OpenRanges.getVarLocs()) {
+ if (VarLocIDs[ID].getEntryValueBackupReg() == SrcReg) {
+ LLVM_DEBUG(dbgs() << "Copy of the entry value: "; MI.dump(););
+ VarLoc EntryValLocCopyBackup = VarLoc::CreateEntryCopyBackupLoc(
+ VarLocIDs[ID].MI, LS, VarLocIDs[ID].Expr, DestReg);
+
+ // Stop tracking the original entry value.
+ OpenRanges.erase(VarLocIDs[ID]);
+
+ // Start tracking the entry value copy.
+ unsigned EntryValCopyLocID = VarLocIDs.insert(EntryValLocCopyBackup);
+ OpenRanges.insert(EntryValCopyLocID, EntryValLocCopyBackup);
+ break;
+ }
+ }
+ }
+
+ if (!SrcRegOp->isKill())
+ return;
+
for (unsigned ID : OpenRanges.getVarLocs()) {
if (VarLocIDs[ID].isDescribedByReg() == SrcReg) {
insertTransferDebugPair(MI, OpenRanges, Transfers, VarLocIDs, ID,
@@ -1115,11 +1321,9 @@
/// This routine creates OpenRanges.
void LiveDebugValues::process(MachineInstr &MI, OpenRangesSet &OpenRanges,
- VarLocMap &VarLocIDs, TransferMap &Transfers,
- DebugParamMap &DebugEntryVals) {
+ VarLocMap &VarLocIDs, TransferMap &Transfers) {
transferDebugValue(MI, OpenRanges, VarLocIDs);
- transferRegisterDef(MI, OpenRanges, VarLocIDs, Transfers,
- DebugEntryVals);
+ transferRegisterDef(MI, OpenRanges, VarLocIDs, Transfers);
transferRegisterCopy(MI, OpenRanges, VarLocIDs, Transfers);
transferSpillOrRestoreInst(MI, OpenRanges, VarLocIDs, Transfers);
}
@@ -1240,6 +1444,8 @@
// The ID location is live-in to MBB -- work out what kind of machine
// location it is and create a DBG_VALUE.
const VarLoc &DiffIt = VarLocIDs[ID];
+ if (DiffIt.isEntryBackupLoc())
+ continue;
MachineInstr *MI = DiffIt.BuildDbgValue(*MBB.getParent());
MBB.insert(MBB.instr_begin(), MI);
@@ -1249,6 +1455,39 @@
}
}
+/// This routine records the entry values of function parameters. The values
+/// could be used as backup values. If we loose the track of some unmodified
+/// parameters, the backup values will be used as a primary locations.
+void LiveDebugValues::recordEntryValues(MachineInstr &MI,
+ OpenRangesSet &OpenRanges,
+ VarLocMap &VarLocIDs) {
+ if (auto *TPC = getAnalysisIfAvailable<TargetPassConfig>()) {
+ auto &TM = TPC->getTM<TargetMachine>();
+ if (!TM.Options.EnableDebugEntryValues)
+ return;
+ }
+
+ // TODO: Add support for parameters that are described as fragments.
+ // TODO: Add support for modified arguments that can be expressed
+ // by using its entry value.
+ // TODO: Add support for local variables that are expressed in terms of
+ // parameters entry values.
+ if (MI.getDebugLoc()->getInlinedAt() ||
+ !MI.getDebugVariable()->isParameter() || MI.isIndirectDebugValue() ||
+ OpenRanges.getEntryValueBackup(DebugVariable(MI)) ||
+ !isRegOtherThanSPAndFP(MI.getOperand(0), MI, TRI) ||
+ MI.getDebugExpression()->getNumElements() != 0)
+ return;
+
+ // Create the entry value and use it as a backup location until it is
+ // valid. It is valid until a parameter is not changed.
+ DIExpression *NewExpr =
+ DIExpression::prepend(MI.getDebugExpression(), DIExpression::EntryValue);
+ VarLoc EntryValLocAsBackup = VarLoc::CreateEntryBackupLoc(MI, LS, NewExpr);
+ unsigned EntryValLocID = VarLocIDs.insert(EntryValLocAsBackup);
+ OpenRanges.insert(EntryValLocID, EntryValLocAsBackup);
+}
+
/// Calculate the liveness information for the given machine function and
/// extend ranges across basic blocks.
bool LiveDebugValues::ExtendRanges(MachineFunction &MF) {
@@ -1285,33 +1524,15 @@
std::greater<unsigned int>>
Pending;
- const TargetLowering *TLI = MF.getSubtarget().getTargetLowering();
- unsigned SP = TLI->getStackPointerRegisterToSaveRestore();
- Register FP = TRI->getFrameRegister(MF);
- auto IsRegOtherThanSPAndFP = [&](const MachineOperand &Op) -> bool {
- return Op.isReg() && Op.getReg() != SP && Op.getReg() != FP;
- };
-
- // Working set of currently collected debug variables mapped to DBG_VALUEs
- // representing candidates for production of debug entry values.
- DebugParamMap DebugEntryVals;
-
MachineBasicBlock &First_MBB = *(MF.begin());
// Only in the case of entry MBB collect DBG_VALUEs representing
// function parameters in order to generate debug entry values for them.
// Currently, we generate debug entry values only for parameters that are
// unmodified throughout the function and located in a register.
- // TODO: Add support for parameters that are described as fragments.
- // TODO: Add support for modified arguments that can be expressed
- // by using its entry value.
- // TODO: Add support for local variables that are expressed in terms of
- // parameters entry values.
- for (auto &MI : First_MBB)
- if (MI.isDebugValue() && !MI.getDebugLoc()->getInlinedAt() &&
- !MI.isIndirectDebugValue() && IsRegOtherThanSPAndFP(MI.getOperand(0)) &&
- !DebugEntryVals.count(MI.getDebugVariable()) &&
- !MI.getDebugExpression()->isFragment())
- DebugEntryVals[MI.getDebugVariable()] = &MI;
+ for (auto &MI : First_MBB) {
+ if (MI.isDebugValue())
+ recordEntryValues(MI, OpenRanges, VarLocIDs);
+ }
// Initialize per-block structures and scan for fragment overlaps.
for (auto &MBB : MF) {
@@ -1369,7 +1590,7 @@
// First load any pending inlocs.
OpenRanges.insertFromLocSet(PendingInLocs[MBB], VarLocIDs);
for (auto &MI : *MBB)
- process(MI, OpenRanges, VarLocIDs, Transfers, DebugEntryVals);
+ process(MI, OpenRanges, VarLocIDs, Transfers);
OLChanged |= transferTerminator(MBB, OpenRanges, OutLocs, VarLocIDs);
LLVM_DEBUG(printVarLocInMBB(MF, OutLocs, VarLocIDs,
Index: llvm/test/DebugInfo/MIR/X86/entry-value-of-modified-param.mir
===================================================================
--- /dev/null
+++ llvm/test/DebugInfo/MIR/X86/entry-value-of-modified-param.mir
@@ -0,0 +1,121 @@
+# RUN: llc -debug-entry-values -run-pass=livedebugvalues -march=x86-64 -o - %s | FileCheck %s
+#
+#extern void fn1 (int, int, int);
+#
+#__attribute__((noinline))
+#int
+#fn2 (int a, int b, int c) {
+# int q = 2 + a;
+#
+# fn1 (5, 6, q);
+#
+# b = b + 7;
+# if (b < 17)
+# return 1;
+# else
+# return 0;
+#}
+#
+# CHECK: ![[ARG_A:.*]] = !DILocalVariable(name: "a"
+# CHECK: ![[ARG_B:.*]] = !DILocalVariable(name: "b"
+# CHECK: ![[ARG_C:.*]] = !DILocalVariable(name: "c"
+# CHECK: DBG_VALUE $edi, $noreg, ![[ARG_A]], !DIExpression(DW_OP_LLVM_entry_value, 1)
+# CHECK: DBG_VALUE $edx, $noreg, ![[ARG_C]], !DIExpression(DW_OP_LLVM_entry_value, 1)
+# CHECK: DBG_VALUE $edi, $noreg, ![[ARG_A]], !DIExpression(DW_OP_LLVM_entry_value, 1)
+# CHECK-NOT: DBG_VALUE $esi, $noreg, ![[ARG_B]], !DIExpression(DW_OP_LLVM_entry_value, 1)
+#
+--- |
+ ; ModuleID = 'test.c'
+ source_filename = "test.c"
+ target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
+ target triple = "x86_64-unknown-linux-gnu"
+
+ ; Function Attrs: noinline nounwind uwtable
+ define dso_local i32 @fn2(i32 %a, i32 %b, i32 %c) local_unnamed_addr !dbg !12 {
+ entry:
+ call void @llvm.dbg.value(metadata i32 %a, metadata !16, metadata !DIExpression()), !dbg !20
+ call void @llvm.dbg.value(metadata i32 %b, metadata !17, metadata !DIExpression()), !dbg !20
+ call void @llvm.dbg.value(metadata i32 %c, metadata !18, metadata !DIExpression()), !dbg !20
+ %add = add nsw i32 %a, 2, !dbg !21
+ call void @llvm.dbg.value(metadata i32 %add, metadata !19, metadata !DIExpression()), !dbg !20
+ tail call void @fn1(i32 5, i32 6, i32 %add), !dbg !22
+ call void @llvm.dbg.value(metadata i32 %b, metadata !17, metadata !DIExpression(DW_OP_plus_uconst, 7, DW_OP_stack_value)), !dbg !20
+ %cmp = icmp slt i32 %b, 10, !dbg !23
+ %. = zext i1 %cmp to i32, !dbg !25
+ ret i32 %., !dbg !26
+ }
+
+ declare !dbg !4 dso_local void @fn1(i32, i32, i32) local_unnamed_addr
+
+ ; Function Attrs: nounwind readnone speculatable willreturn
+ declare void @llvm.dbg.value(metadata, metadata, metadata)
+
+ !llvm.dbg.cu = !{!0}
+ !llvm.module.flags = !{!8, !9, !10}
+ !llvm.ident = !{!11}
+
+ !0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang version 10.0.0", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, retainedTypes: !3, nameTableKind: None)
+ !1 = !DIFile(filename: "test.c", directory: "/dir")
+ !2 = !{}
+ !3 = !{!4}
+ !4 = !DISubprogram(name: "fn1", scope: !1, file: !1, line: 1, type: !5, flags: DIFlagPrototyped, spFlags: DISPFlagOptimized, retainedNodes: !2)
+ !5 = !DISubroutineType(types: !6)
+ !6 = !{null, !7, !7, !7}
+ !7 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
+ !8 = !{i32 2, !"Dwarf Version", i32 4}
+ !9 = !{i32 2, !"Debug Info Version", i32 3}
+ !10 = !{i32 1, !"wchar_size", i32 4}
+ !11 = !{!"clang version 10.0.0"}
+ !12 = distinct !DISubprogram(name: "fn2", scope: !1, file: !1, line: 5, type: !13, scopeLine: 6, flags: DIFlagPrototyped | DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !15)
+ !13 = !DISubroutineType(types: !14)
+ !14 = !{!7, !7, !7, !7}
+ !15 = !{!16, !17, !18, !19}
+ !16 = !DILocalVariable(name: "a", arg: 1, scope: !12, file: !1, line: 5, type: !7)
+ !17 = !DILocalVariable(name: "b", arg: 2, scope: !12, file: !1, line: 5, type: !7)
+ !18 = !DILocalVariable(name: "c", arg: 3, scope: !12, file: !1, line: 5, type: !7)
+ !19 = !DILocalVariable(name: "q", scope: !12, file: !1, line: 7, type: !7)
+ !20 = !DILocation(line: 0, scope: !12)
+ !21 = !DILocation(line: 7, column: 15, scope: !12)
+ !22 = !DILocation(line: 9, column: 5, scope: !12)
+ !23 = !DILocation(line: 12, column: 11, scope: !24)
+ !24 = distinct !DILexicalBlock(scope: !12, file: !1, line: 12, column: 9)
+ !25 = !DILocation(line: 0, scope: !24)
+ !26 = !DILocation(line: 16, column: 1, scope: !12)
+
+...
+---
+name: fn2
+alignment: 16
+callSites:
+ - { bb: 0, offset: 14, fwdArgRegs:
+ - { arg: 0, reg: '$edi' }
+ - { arg: 1, reg: '$esi' }
+ - { arg: 2, reg: '$edx' } }
+body: |
+ bb.0.entry:
+ liveins: $edi, $esi, $rbx
+
+ DBG_VALUE $edi, $noreg, !16, !DIExpression(), debug-location !20
+ DBG_VALUE $esi, $noreg, !17, !DIExpression(), debug-location !20
+ DBG_VALUE $edx, $noreg, !18, !DIExpression(), debug-location !20
+ frame-setup PUSH64r killed $rbx, implicit-def $rsp, implicit $rsp
+ CFI_INSTRUCTION def_cfa_offset 16
+ CFI_INSTRUCTION offset $rbx, -16
+ $ebx = MOV32rr $esi
+ DBG_VALUE $ebx, $noreg, !17, !DIExpression(), debug-location !20
+ renamable $edi = KILL $edi, implicit-def $rdi
+ DBG_VALUE $edi, $noreg, !16, !DIExpression(), debug-location !20
+ renamable $edx = LEA64_32r killed renamable $rdi, 1, $noreg, 2, $noreg, debug-location !21
+ DBG_VALUE $edx, $noreg, !19, !DIExpression(), debug-location !20
+ $edi = MOV32ri 5, debug-location !22
+ $esi = MOV32ri 6, debug-location !22
+ CALL64pcrel32 @fn1, csr_64, implicit $rsp, implicit $ssp, implicit $edi, implicit $esi, implicit $edx, implicit-def $rsp, implicit-def $ssp, debug-location !22
+ DBG_VALUE $ebx, $noreg, !17, !DIExpression(DW_OP_plus_uconst, 7, DW_OP_stack_value), debug-location !20
+ renamable $eax = XOR32rr undef $eax, undef $eax, implicit-def dead $eflags, debug-location !23
+ CMP32ri8 killed renamable $ebx, 10, implicit-def $eflags, debug-location !23
+ renamable $al = SETCCr 12, implicit killed $eflags, implicit killed $eax, implicit-def $eax, debug-location !23
+ $rbx = frame-destroy POP64r implicit-def $rsp, implicit $rsp, debug-location !26
+ CFI_INSTRUCTION def_cfa_offset 8, debug-location !26
+ RETQ $eax, debug-location !26
+
+...
Index: llvm/test/DebugInfo/MIR/X86/entry-values-diamond-bbs.mir
===================================================================
--- /dev/null
+++ llvm/test/DebugInfo/MIR/X86/entry-values-diamond-bbs.mir
@@ -0,0 +1,169 @@
+# RUN: llc -debug-entry-values -run-pass=livedebugvalues -march=x86-64 -o - %s | FileCheck %s
+#
+# The test case was artificially adjusted, in order to make proper diamond basic
+# block structure relevant to the debug entry values propagation.
+#
+# CHECK: ![[ARG_B:.*]] = !DILocalVariable(name: "b"
+# CHECK: bb.0.entry
+# CHECK: DBG_VALUE $esi, $noreg, ![[ARG_B]], !DIExpression()
+# CHECK: bb.1.if.then
+# CHECK: DBG_VALUE $esi, $noreg, ![[ARG_B]], !DIExpression(DW_OP_LLVM_entry_value, 1)
+# CHECK: bb.2.if.else
+# CHECK: DBG_VALUE $esi, $noreg, ![[ARG_B]], !DIExpression(DW_OP_LLVM_entry_value, 1)
+# CHECK: bb.3.if.end
+# CHECK: DBG_VALUE $esi, $noreg, ![[ARG_B]], !DIExpression(DW_OP_LLVM_entry_value, 1)
+#
+--- |
+ ; ModuleID = 'test.c'
+ source_filename = "test.c"
+ target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
+ target triple = "x86_64-unknown-linux-gnu"
+
+ ; Function Attrs: noinline nounwind uwtable
+ define dso_local i32 @fn2(i32 %a, i32 %b, i32 %c) local_unnamed_addr !dbg !12 {
+ entry:
+ call void @llvm.dbg.value(metadata i32 %a, metadata !16, metadata !DIExpression()), !dbg !20
+ call void @llvm.dbg.value(metadata i32 %b, metadata !17, metadata !DIExpression()), !dbg !20
+ call void @llvm.dbg.value(metadata i32 %c, metadata !18, metadata !DIExpression()), !dbg !20
+ %add = add nsw i32 %a, 2, !dbg !21
+ call void @llvm.dbg.value(metadata i32 %add, metadata !19, metadata !DIExpression()), !dbg !20
+ tail call void @fn1(i32 5, i32 6, i32 %add) #3, !dbg !22
+ %cmp = icmp slt i32 %b, 17, !dbg !23
+ br i1 %cmp, label %if.then, label %if.else, !dbg !25
+
+ if.then: ; preds = %entry
+ %add1 = add nsw i32 %b, 7, !dbg !26
+ call void @llvm.dbg.value(metadata i32 %add1, metadata !17, metadata !DIExpression()), !dbg !20
+ tail call void @fn1(i32 5, i32 %add1, i32 %c) #3, !dbg !28
+ br label %if.end, !dbg !29
+
+ if.else: ; preds = %entry
+ %add2 = add nuw nsw i32 %b, 1, !dbg !30
+ call void @llvm.dbg.value(metadata i32 %add2, metadata !17, metadata !DIExpression()), !dbg !20
+ tail call void @fn1(i32 1, i32 %add2, i32 %c) #3, !dbg !32
+ br label %if.end
+
+ if.end: ; preds = %if.else, %if.then
+ %b.addr.0 = phi i32 [ %add1, %if.then ], [ %add2, %if.else ], !dbg !33
+ call void @llvm.dbg.value(metadata i32 %b.addr.0, metadata !17, metadata !DIExpression()), !dbg !20
+ ret i32 %b.addr.0, !dbg !34
+ }
+
+ declare !dbg !4 dso_local void @fn1(i32, i32, i32) local_unnamed_addr
+
+ ; Function Attrs: nounwind readnone speculatable willreturn
+ declare void @llvm.dbg.value(metadata, metadata, metadata)
+
+ !llvm.dbg.cu = !{!0}
+ !llvm.module.flags = !{!8, !9, !10}
+ !llvm.ident = !{!11}
+
+ !0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang version 10.0.0", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, retainedTypes: !3, nameTableKind: None)
+ !1 = !DIFile(filename: "test.c", directory: "/dir")
+ !2 = !{}
+ !3 = !{!4}
+ !4 = !DISubprogram(name: "fn1", scope: !1, file: !1, line: 1, type: !5, flags: DIFlagPrototyped, spFlags: DISPFlagOptimized, retainedNodes: !2)
+ !5 = !DISubroutineType(types: !6)
+ !6 = !{null, !7, !7, !7}
+ !7 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
+ !8 = !{i32 2, !"Dwarf Version", i32 4}
+ !9 = !{i32 2, !"Debug Info Version", i32 3}
+ !10 = !{i32 1, !"wchar_size", i32 4}
+ !11 = !{!"clang version 10.0.0"}
+ !12 = distinct !DISubprogram(name: "fn2", scope: !1, file: !1, line: 5, type: !13, scopeLine: 6, flags: DIFlagPrototyped | DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !15)
+ !13 = !DISubroutineType(types: !14)
+ !14 = !{!7, !7, !7, !7}
+ !15 = !{!16, !17, !18, !19}
+ !16 = !DILocalVariable(name: "a", arg: 1, scope: !12, file: !1, line: 5, type: !7)
+ !17 = !DILocalVariable(name: "b", arg: 2, scope: !12, file: !1, line: 5, type: !7)
+ !18 = !DILocalVariable(name: "c", arg: 3, scope: !12, file: !1, line: 5, type: !7)
+ !19 = !DILocalVariable(name: "q", scope: !12, file: !1, line: 7, type: !7)
+ !20 = !DILocation(line: 0, scope: !12)
+ !21 = !DILocation(line: 7, column: 15, scope: !12)
+ !22 = !DILocation(line: 9, column: 5, scope: !12)
+ !23 = !DILocation(line: 11, column: 11, scope: !24)
+ !24 = distinct !DILexicalBlock(scope: !12, file: !1, line: 11, column: 9)
+ !25 = !DILocation(line: 11, column: 9, scope: !12)
+ !26 = !DILocation(line: 12, column: 13, scope: !27)
+ !27 = distinct !DILexicalBlock(scope: !24, file: !1, line: 11, column: 17)
+ !28 = !DILocation(line: 13, column: 8, scope: !27)
+ !29 = !DILocation(line: 14, column: 5, scope: !27)
+ !30 = !DILocation(line: 15, column: 13, scope: !31)
+ !31 = distinct !DILexicalBlock(scope: !24, file: !1, line: 14, column: 12)
+ !32 = !DILocation(line: 16, column: 7, scope: !31)
+ !33 = !DILocation(line: 0, scope: !24)
+ !34 = !DILocation(line: 19, column: 5, scope: !12)
+
+...
+---
+name: fn2
+alignment: 16
+fixedStack:
+ - { id: 0, type: spill-slot, offset: -24, size: 8, alignment: 8, stack-id: default,
+ callee-saved-register: '$rbx', callee-saved-restored: true, debug-info-variable: '',
+ debug-info-expression: '', debug-info-location: '' }
+ - { id: 1, type: spill-slot, offset: -16, size: 8, alignment: 16, stack-id: default,
+ callee-saved-register: '$rbp', callee-saved-restored: true, debug-info-variable: '',
+ debug-info-expression: '', debug-info-location: '' }
+body: |
+ bb.0.entry:
+ successors: %bb.1(0x40000000), %bb.2(0x40000000)
+ liveins: $edi, $edx, $esi, $rbp, $rbx
+
+ DBG_VALUE $edi, $noreg, !16, !DIExpression(), debug-location !20
+ DBG_VALUE $esi, $noreg, !17, !DIExpression(), debug-location !20
+ DBG_VALUE $edx, $noreg, !18, !DIExpression(), debug-location !20
+ frame-setup PUSH64r killed $rbp, implicit-def $rsp, implicit $rsp
+ CFI_INSTRUCTION def_cfa_offset 16
+ frame-setup PUSH64r killed $rbx, implicit-def $rsp, implicit $rsp
+ CFI_INSTRUCTION def_cfa_offset 24
+ frame-setup PUSH64r undef $rax, implicit-def $rsp, implicit $rsp
+ CFI_INSTRUCTION def_cfa_offset 32
+ CFI_INSTRUCTION offset $rbx, -24
+ CFI_INSTRUCTION offset $rbp, -16
+ $ebp = MOV32rr $edx
+ DBG_VALUE $ebp, $noreg, !18, !DIExpression(), debug-location !20
+ renamable $edi = KILL $edi, implicit-def $rdi
+ DBG_VALUE $edi, $noreg, !16, !DIExpression(), debug-location !20
+ renamable $edx = LEA64_32r killed renamable $rdi, 1, $noreg, 2, $noreg, debug-location !21
+ DBG_VALUE $edx, $noreg, !19, !DIExpression(), debug-location !20
+ $edi = MOV32ri 5, debug-location !22
+ CMP32ri8 renamable $ebp, 16, implicit-def $eflags, debug-location !23
+ JCC_1 %bb.2, 15, implicit killed $eflags, debug-location !25
+
+ bb.1.if.then:
+ successors: %bb.3(0x80000000)
+ liveins: $ebp, $ebx, $esi
+
+ $ebx = MOV32rr $esi
+ DBG_VALUE $ebx, $noreg, !17, !DIExpression(), debug-location !20
+ $esi = MOV32ri 5, debug-location !28
+ $ebx = MOV32ri 1
+ JMP_1 %bb.3
+
+ bb.2.if.else:
+ successors: %bb.3(0x80000000)
+ liveins: $ebp, $ebx, $esi
+
+ $ebx = MOV32rr $esi
+ DBG_VALUE $ebx, $noreg, !17, !DIExpression(), debug-location !20
+ $esi = MOV32ri 1, debug-location !32
+ $ebx = MOV32ri 2
+
+ bb.3.if.end:
+ liveins: $ebx, $edi, $ebp
+
+ $esi = MOV32rr $ebx, debug-location !33
+ $edx = MOV32rr killed $ebp, debug-location !33
+ CALL64pcrel32 @fn1, csr_64, implicit $rsp, implicit $ssp, implicit $edi, implicit $esi, implicit $edx, implicit-def $rsp, implicit-def $ssp, debug-location !33
+ DBG_VALUE $ebx, $noreg, !17, !DIExpression(), debug-location !20
+ $eax = MOV32rr killed $ebx, debug-location !34
+ $rsp = frame-destroy ADD64ri8 $rsp, 8, implicit-def dead $eflags, debug-location !34
+ CFI_INSTRUCTION def_cfa_offset 24, debug-location !34
+ $rbx = frame-destroy POP64r implicit-def $rsp, implicit $rsp, debug-location !34
+ CFI_INSTRUCTION def_cfa_offset 16, debug-location !34
+ $rbp = frame-destroy POP64r implicit-def $rsp, implicit $rsp, debug-location !34
+ CFI_INSTRUCTION def_cfa_offset 8, debug-location !34
+ RETQ killed $eax, debug-location !34
+
+...
Index: llvm/test/DebugInfo/MIR/X86/kill-entry-value-after-diamond-bbs.mir
===================================================================
--- /dev/null
+++ llvm/test/DebugInfo/MIR/X86/kill-entry-value-after-diamond-bbs.mir
@@ -0,0 +1,170 @@
+# RUN: llc -debug-entry-values -run-pass=livedebugvalues -march=x86-64 -o - %s | FileCheck %s
+#
+# The test case was artificially adjusted, in order to make proper diamond basic
+# block structure relevant to the debug entry values clobbering.
+#
+# CHECK: ![[ARG_B:.*]] = !DILocalVariable(name: "b"
+# CHECK: bb.0.entry
+# CHECK: DBG_VALUE $esi, $noreg, ![[ARG_B]], !DIExpression()
+# CHECK: bb.1.if.then
+# CHECK: DBG_VALUE $esi, $noreg, ![[ARG_B]], !DIExpression(DW_OP_LLVM_entry_value, 1)
+# CHECK: bb.2.if.else
+# CHECK: DBG_VALUE $esi, $noreg, ![[ARG_B]], !DIExpression(DW_OP_LLVM_entry_value, 1)
+# CHECK: bb.3.if.end
+# CHECK-NOT: DBG_VALUE $esi, $noreg, ![[ARG_B]], !DIExpression(DW_OP_LLVM_entry_value, 1)
+#
+--- |
+ ; ModuleID = 'test.c'
+ source_filename = "test.c"
+ target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
+ target triple = "x86_64-unknown-linux-gnu"
+
+ ; Function Attrs: noinline nounwind uwtable
+ define dso_local i32 @fn2(i32 %a, i32 %b, i32 %c) local_unnamed_addr !dbg !12 {
+ entry:
+ call void @llvm.dbg.value(metadata i32 %a, metadata !16, metadata !DIExpression()), !dbg !20
+ call void @llvm.dbg.value(metadata i32 %b, metadata !17, metadata !DIExpression()), !dbg !20
+ call void @llvm.dbg.value(metadata i32 %c, metadata !18, metadata !DIExpression()), !dbg !20
+ %add = add nsw i32 %a, 2, !dbg !21
+ call void @llvm.dbg.value(metadata i32 %add, metadata !19, metadata !DIExpression()), !dbg !20
+ tail call void @fn1(i32 5, i32 6, i32 %add), !dbg !22
+ %cmp = icmp slt i32 %b, 17, !dbg !23
+ br i1 %cmp, label %if.then, label %if.else, !dbg !25
+
+ if.then: ; preds = %entry
+ %add1 = add nsw i32 %b, 7, !dbg !26
+ call void @llvm.dbg.value(metadata i32 %add1, metadata !17, metadata !DIExpression()), !dbg !20
+ tail call void @fn1(i32 5, i32 %add1, i32 %c), !dbg !28
+ br label %if.end, !dbg !29
+
+ if.else: ; preds = %entry
+ %add2 = add nuw nsw i32 %b, 1, !dbg !30
+ call void @llvm.dbg.value(metadata i32 %add2, metadata !17, metadata !DIExpression()), !dbg !20
+ tail call void @fn1(i32 1, i32 %add2, i32 %c), !dbg !32
+ br label %if.end
+
+ if.end: ; preds = %if.else, %if.then
+ %b.addr.0 = phi i32 [ %add1, %if.then ], [ %add2, %if.else ], !dbg !33
+ call void @llvm.dbg.value(metadata i32 %b.addr.0, metadata !17, metadata !DIExpression()), !dbg !20
+ ret i32 %b.addr.0, !dbg !34
+ }
+
+ declare !dbg !4 dso_local void @fn1(i32, i32, i32) local_unnamed_addr
+
+ ; Function Attrs: nounwind readnone speculatable willreturn
+ declare void @llvm.dbg.value(metadata, metadata, metadata)
+
+ !llvm.dbg.cu = !{!0}
+ !llvm.module.flags = !{!8, !9, !10}
+ !llvm.ident = !{!11}
+
+ !0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang version 10.0.0", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, retainedTypes: !3, nameTableKind: None)
+ !1 = !DIFile(filename: "test.c", directory: "/dir")
+ !2 = !{}
+ !3 = !{!4}
+ !4 = !DISubprogram(name: "fn1", scope: !1, file: !1, line: 1, type: !5, flags: DIFlagPrototyped, spFlags: DISPFlagOptimized, retainedNodes: !2)
+ !5 = !DISubroutineType(types: !6)
+ !6 = !{null, !7, !7, !7}
+ !7 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
+ !8 = !{i32 2, !"Dwarf Version", i32 4}
+ !9 = !{i32 2, !"Debug Info Version", i32 3}
+ !10 = !{i32 1, !"wchar_size", i32 4}
+ !11 = !{!"clang version 10.0.0"}
+ !12 = distinct !DISubprogram(name: "fn2", scope: !1, file: !1, line: 5, type: !13, scopeLine: 6, flags: DIFlagPrototyped | DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !15)
+ !13 = !DISubroutineType(types: !14)
+ !14 = !{!7, !7, !7, !7}
+ !15 = !{!16, !17, !18, !19}
+ !16 = !DILocalVariable(name: "a", arg: 1, scope: !12, file: !1, line: 5, type: !7)
+ !17 = !DILocalVariable(name: "b", arg: 2, scope: !12, file: !1, line: 5, type: !7)
+ !18 = !DILocalVariable(name: "c", arg: 3, scope: !12, file: !1, line: 5, type: !7)
+ !19 = !DILocalVariable(name: "q", scope: !12, file: !1, line: 7, type: !7)
+ !20 = !DILocation(line: 0, scope: !12)
+ !21 = !DILocation(line: 7, column: 15, scope: !12)
+ !22 = !DILocation(line: 9, column: 5, scope: !12)
+ !23 = !DILocation(line: 11, column: 11, scope: !24)
+ !24 = distinct !DILexicalBlock(scope: !12, file: !1, line: 11, column: 9)
+ !25 = !DILocation(line: 11, column: 9, scope: !12)
+ !26 = !DILocation(line: 12, column: 13, scope: !27)
+ !27 = distinct !DILexicalBlock(scope: !24, file: !1, line: 11, column: 17)
+ !28 = !DILocation(line: 13, column: 8, scope: !27)
+ !29 = !DILocation(line: 14, column: 5, scope: !27)
+ !30 = !DILocation(line: 15, column: 13, scope: !31)
+ !31 = distinct !DILexicalBlock(scope: !24, file: !1, line: 14, column: 12)
+ !32 = !DILocation(line: 16, column: 7, scope: !31)
+ !33 = !DILocation(line: 0, scope: !24)
+ !34 = !DILocation(line: 19, column: 5, scope: !12)
+
+...
+---
+name: fn2
+alignment: 16
+fixedStack:
+ - { id: 0, type: spill-slot, offset: -24, size: 8, alignment: 8, stack-id: default,
+ callee-saved-register: '$rbx', callee-saved-restored: true, debug-info-variable: '',
+ debug-info-expression: '', debug-info-location: '' }
+ - { id: 1, type: spill-slot, offset: -16, size: 8, alignment: 16, stack-id: default,
+ callee-saved-register: '$rbp', callee-saved-restored: true, debug-info-variable: '',
+ debug-info-expression: '', debug-info-location: '' }
+body: |
+ bb.0.entry:
+ successors: %bb.1(0x40000000), %bb.2(0x40000000)
+ liveins: $edi, $edx, $esi, $rbp, $rbx
+
+ DBG_VALUE $edi, $noreg, !16, !DIExpression(), debug-location !20
+ DBG_VALUE $esi, $noreg, !17, !DIExpression(), debug-location !20
+ DBG_VALUE $edx, $noreg, !18, !DIExpression(), debug-location !20
+ frame-setup PUSH64r killed $rbp, implicit-def $rsp, implicit $rsp
+ CFI_INSTRUCTION def_cfa_offset 16
+ frame-setup PUSH64r killed $rbx, implicit-def $rsp, implicit $rsp
+ CFI_INSTRUCTION def_cfa_offset 24
+ frame-setup PUSH64r undef $rax, implicit-def $rsp, implicit $rsp
+ CFI_INSTRUCTION def_cfa_offset 32
+ CFI_INSTRUCTION offset $rbx, -24
+ CFI_INSTRUCTION offset $rbp, -16
+ $ebp = MOV32rr $edx
+ DBG_VALUE $ebp, $noreg, !18, !DIExpression(), debug-location !20
+ renamable $edi = KILL $edi, implicit-def $rdi
+ DBG_VALUE $edi, $noreg, !16, !DIExpression(), debug-location !20
+ renamable $edx = LEA64_32r killed renamable $rdi, 1, $noreg, 2, $noreg, debug-location !21
+ DBG_VALUE $edx, $noreg, !19, !DIExpression(), debug-location !20
+ $edi = MOV32ri 5, debug-location !22
+ CMP32ri8 renamable $ebp, 16, implicit-def $eflags, debug-location !23
+ JCC_1 %bb.2, 15, implicit killed $eflags, debug-location !25
+
+ bb.1.if.then:
+ successors: %bb.3(0x80000000)
+ liveins: $ebp, $ebx, $esi
+
+ $ebx = MOV32rr $esi
+ DBG_VALUE $ebx, $noreg, !17, !DIExpression(), debug-location !20
+ $esi = MOV32ri 5, debug-location !28
+ $ebx = MOV32ri 1
+ JMP_1 %bb.3
+
+ bb.2.if.else:
+ successors: %bb.3(0x80000000)
+ liveins: $ebp, $ebx, $esi
+
+ $ebp = MOV32rr $esi
+ DBG_VALUE $ebp, $noreg, !17, !DIExpression(), debug-location !20
+ $esi = MOV32ri 1, debug-location !32
+ $ebp = MOV32ri 2
+
+ bb.3.if.end:
+ liveins: $ebx, $edi, $ebp
+
+ $esi = MOV32rr $ebx, debug-location !33
+ $edx = MOV32rr killed $ebp, debug-location !33
+ CALL64pcrel32 @fn1, csr_64, implicit $rsp, implicit $ssp, implicit $edi, implicit $esi, implicit $edx, implicit-def $rsp, implicit-def $ssp, debug-location !33
+ DBG_VALUE $ebx, $noreg, !17, !DIExpression(), debug-location !20
+ $eax = MOV32rr killed $ebx, debug-location !34
+ $rsp = frame-destroy ADD64ri8 $rsp, 8, implicit-def dead $eflags, debug-location !34
+ CFI_INSTRUCTION def_cfa_offset 24, debug-location !34
+ $rbx = frame-destroy POP64r implicit-def $rsp, implicit $rsp, debug-location !34
+ CFI_INSTRUCTION def_cfa_offset 16, debug-location !34
+ $rbp = frame-destroy POP64r implicit-def $rsp, implicit $rsp, debug-location !34
+ CFI_INSTRUCTION def_cfa_offset 8, debug-location !34
+ RETQ killed $eax, debug-location !34
+
+...
+
Index: llvm/test/DebugInfo/MIR/X86/propagate-entry-value-cross-bbs.mir
===================================================================
--- /dev/null
+++ llvm/test/DebugInfo/MIR/X86/propagate-entry-value-cross-bbs.mir
@@ -0,0 +1,184 @@
+# RUN: llc -debug-entry-values -run-pass=livedebugvalues -march=x86-64 -o - %s | FileCheck %s
+#
+#extern void fn1 (int, int, int);
+#__attribute__((noinline))
+#int
+#fn2 (int a, int b, int c) {
+# int q = 2 + a;
+# fn1 (5, 6, q);
+# if (b < 17) {
+# b = b + 7;
+# fn1 (5, b, q);
+# } else {
+# b = b + 1;
+# fn1 (1, b, q);
+# }
+# return b;
+#}
+# CHECK: ![[ARG_C:.*]] = !DILocalVariable(name: "c"
+# CHECK: bb.0.entry:
+# CHECK: DBG_VALUE $edx, $noreg, ![[ARG_C]], !DIExpression(DW_OP_LLVM_entry_value, 1)
+# CHECK: bb.1.if.then:
+# CHECK: DBG_VALUE $edx, $noreg, ![[ARG_C]], !DIExpression(DW_OP_LLVM_entry_value, 1)
+# CHECK: bb.2.if.else:
+# CHECK: DBG_VALUE $edx, $noreg, ![[ARG_C]], !DIExpression(DW_OP_LLVM_entry_value, 1)
+# CHECK: bb.3.if.end:
+# CHECK: DBG_VALUE $edx, $noreg, ![[ARG_C]], !DIExpression(DW_OP_LLVM_entry_value, 1)
+#
+--- |
+ ; ModuleID = 'test.c'
+ source_filename = "test.c"
+ target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
+ target triple = "x86_64-unknown-linux-gnu"
+
+ ; Function Attrs: noinline nounwind uwtable
+ define dso_local i32 @fn2(i32 %a, i32 %b, i32 %c) local_unnamed_addr !dbg !12 {
+ entry:
+ call void @llvm.dbg.value(metadata i32 %a, metadata !16, metadata !DIExpression()), !dbg !20
+ call void @llvm.dbg.value(metadata i32 %b, metadata !17, metadata !DIExpression()), !dbg !20
+ call void @llvm.dbg.value(metadata i32 %c, metadata !18, metadata !DIExpression()), !dbg !20
+ %add = add nsw i32 %a, 2, !dbg !21
+ call void @llvm.dbg.value(metadata i32 %add, metadata !19, metadata !DIExpression()), !dbg !20
+ tail call void @fn1(i32 5, i32 6, i32 %add), !dbg !22
+ %cmp = icmp slt i32 %b, 17, !dbg !23
+ br i1 %cmp, label %if.then, label %if.else, !dbg !25
+
+ if.then: ; preds = %entry
+ %add1 = add nsw i32 %b, 7, !dbg !26
+ call void @llvm.dbg.value(metadata i32 %add1, metadata !17, metadata !DIExpression()), !dbg !20
+ tail call void @fn1(i32 5, i32 %add1, i32 %add), !dbg !28
+ br label %if.end, !dbg !29
+
+ if.else: ; preds = %entry
+ %add2 = add nuw nsw i32 %b, 1, !dbg !30
+ call void @llvm.dbg.value(metadata i32 %add2, metadata !17, metadata !DIExpression()), !dbg !20
+ tail call void @fn1(i32 1, i32 %add2, i32 %add), !dbg !32
+ br label %if.end
+
+ if.end: ; preds = %if.else, %if.then
+ %b.addr.0 = phi i32 [ %add1, %if.then ], [ %add2, %if.else ], !dbg !33
+ call void @llvm.dbg.value(metadata i32 %b.addr.0, metadata !17, metadata !DIExpression()), !dbg !20
+ ret i32 %b.addr.0, !dbg !34
+ }
+
+ declare !dbg !4 dso_local void @fn1(i32, i32, i32) local_unnamed_addr
+
+ ; Function Attrs: nounwind readnone speculatable willreturn
+ declare void @llvm.dbg.value(metadata, metadata, metadata)
+
+ !llvm.dbg.cu = !{!0}
+ !llvm.module.flags = !{!8, !9, !10}
+ !llvm.ident = !{!11}
+
+ !0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang version 10.0.0", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, retainedTypes: !3, nameTableKind: None)
+ !1 = !DIFile(filename: "test.c", directory: "/")
+ !2 = !{}
+ !3 = !{!4}
+ !4 = !DISubprogram(name: "fn1", scope: !1, file: !1, line: 1, type: !5, flags: DIFlagPrototyped, spFlags: DISPFlagOptimized, retainedNodes: !2)
+ !5 = !DISubroutineType(types: !6)
+ !6 = !{null, !7, !7, !7}
+ !7 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
+ !8 = !{i32 2, !"Dwarf Version", i32 4}
+ !9 = !{i32 2, !"Debug Info Version", i32 3}
+ !10 = !{i32 1, !"wchar_size", i32 4}
+ !11 = !{!"clang version 10.0.0"}
+ !12 = distinct !DISubprogram(name: "fn2", scope: !1, file: !1, line: 5, type: !13, scopeLine: 6, flags: DIFlagPrototyped | DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !15)
+ !13 = !DISubroutineType(types: !14)
+ !14 = !{!7, !7, !7, !7}
+ !15 = !{!16, !17, !18, !19}
+ !16 = !DILocalVariable(name: "a", arg: 1, scope: !12, file: !1, line: 5, type: !7)
+ !17 = !DILocalVariable(name: "b", arg: 2, scope: !12, file: !1, line: 5, type: !7)
+ !18 = !DILocalVariable(name: "c", arg: 3, scope: !12, file: !1, line: 5, type: !7)
+ !19 = !DILocalVariable(name: "q", scope: !12, file: !1, line: 7, type: !7)
+ !20 = !DILocation(line: 0, scope: !12)
+ !21 = !DILocation(line: 7, column: 15, scope: !12)
+ !22 = !DILocation(line: 9, column: 5, scope: !12)
+ !23 = !DILocation(line: 11, column: 11, scope: !24)
+ !24 = distinct !DILexicalBlock(scope: !12, file: !1, line: 11, column: 9)
+ !25 = !DILocation(line: 11, column: 9, scope: !12)
+ !26 = !DILocation(line: 12, column: 13, scope: !27)
+ !27 = distinct !DILexicalBlock(scope: !24, file: !1, line: 11, column: 17)
+ !28 = !DILocation(line: 13, column: 8, scope: !27)
+ !29 = !DILocation(line: 14, column: 5, scope: !27)
+ !30 = !DILocation(line: 15, column: 13, scope: !31)
+ !31 = distinct !DILexicalBlock(scope: !24, file: !1, line: 14, column: 12)
+ !32 = !DILocation(line: 16, column: 7, scope: !31)
+ !33 = !DILocation(line: 0, scope: !24)
+ !34 = !DILocation(line: 19, column: 5, scope: !12)
+
+...
+---
+name: fn2
+alignment: 16
+callSites:
+ - { bb: 0, offset: 20, fwdArgRegs:
+ - { arg: 0, reg: '$edi' }
+ - { arg: 1, reg: '$esi' }
+ - { arg: 2, reg: '$edx' } }
+ - { bb: 3, offset: 2, fwdArgRegs:
+ - { arg: 0, reg: '$edi' }
+ - { arg: 1, reg: '$esi' }
+ - { arg: 2, reg: '$edx' } }
+body: |
+ bb.0.entry:
+ successors: %bb.1(0x40000000), %bb.2(0x40000000)
+ liveins: $edi, $esi, $rbp, $rbx
+
+ DBG_VALUE $edi, $noreg, !16, !DIExpression(), debug-location !20
+ DBG_VALUE $esi, $noreg, !17, !DIExpression(), debug-location !20
+ DBG_VALUE $edx, $noreg, !18, !DIExpression(), debug-location !20
+ frame-setup PUSH64r killed $rbp, implicit-def $rsp, implicit $rsp
+ CFI_INSTRUCTION def_cfa_offset 16
+ frame-setup PUSH64r killed $rbx, implicit-def $rsp, implicit $rsp
+ CFI_INSTRUCTION def_cfa_offset 24
+ frame-setup PUSH64r undef $rax, implicit-def $rsp, implicit $rsp
+ CFI_INSTRUCTION def_cfa_offset 32
+ CFI_INSTRUCTION offset $rbx, -24
+ CFI_INSTRUCTION offset $rbp, -16
+ $ebx = MOV32rr $esi
+ DBG_VALUE $ebx, $noreg, !17, !DIExpression(), debug-location !20
+ $ebp = MOV32rr $edi
+ DBG_VALUE $ebp, $noreg, !16, !DIExpression(), debug-location !20
+ renamable $ebp = nsw ADD32ri8 killed renamable $ebp, 2, implicit-def dead $eflags, debug-location !21
+ DBG_VALUE $ebp, $noreg, !19, !DIExpression(), debug-location !20
+ $edi = MOV32ri 5, debug-location !22
+ $esi = MOV32ri 6, debug-location !22
+ $edx = MOV32rr $ebp, debug-location !22
+ CALL64pcrel32 @fn1, csr_64, implicit $rsp, implicit $ssp, implicit $edi, implicit $esi, implicit killed $edx, implicit-def $rsp, implicit-def $ssp, debug-location !22
+ CMP32ri8 renamable $ebx, 16, implicit-def $eflags, debug-location !23
+ JCC_1 %bb.2, 15, implicit killed $eflags, debug-location !25
+
+ bb.1.if.then:
+ successors: %bb.3(0x80000000)
+ liveins: $ebp, $ebx
+
+ renamable $ebx = nsw ADD32ri8 killed renamable $ebx, 7, implicit-def dead $eflags, debug-location !26
+ DBG_VALUE $ebx, $noreg, !17, !DIExpression(), debug-location !20
+ $edi = MOV32ri 5, debug-location !28
+ JMP_1 %bb.3
+
+ bb.2.if.else:
+ successors: %bb.3(0x80000000)
+ liveins: $ebp, $ebx
+
+ renamable $ebx = nuw nsw ADD32ri8 killed renamable $ebx, 1, implicit-def dead $eflags, debug-location !30
+ DBG_VALUE $ebx, $noreg, !17, !DIExpression(), debug-location !20
+ $edi = MOV32ri 1, debug-location !32
+
+ bb.3.if.end:
+ liveins: $ebx, $edi, $ebp
+
+ $esi = MOV32rr $ebx, debug-location !33
+ $edx = MOV32rr killed $ebp, debug-location !33
+ CALL64pcrel32 @fn1, csr_64, implicit $rsp, implicit $ssp, implicit $edi, implicit $esi, implicit killed $edx, implicit-def $rsp, implicit-def $ssp, debug-location !33
+ DBG_VALUE $ebx, $noreg, !17, !DIExpression(), debug-location !20
+ $eax = MOV32rr killed $ebx, debug-location !34
+ $rsp = frame-destroy ADD64ri8 $rsp, 8, implicit-def dead $eflags, debug-location !34
+ CFI_INSTRUCTION def_cfa_offset 24, debug-location !34
+ $rbx = frame-destroy POP64r implicit-def $rsp, implicit $rsp, debug-location !34
+ CFI_INSTRUCTION def_cfa_offset 16, debug-location !34
+ $rbp = frame-destroy POP64r implicit-def $rsp, implicit $rsp, debug-location !34
+ CFI_INSTRUCTION def_cfa_offset 8, debug-location !34
+ RETQ killed $eax, debug-location !34
+
+...