[llvm] r206780 - Use value semantics to manage DbgVariables rather than dynamic allocation/pointers.
David Blaikie
dblaikie at gmail.com
Mon Apr 21 13:13:10 PDT 2014
Author: dblaikie
Date: Mon Apr 21 15:13:09 2014
New Revision: 206780
URL: http://llvm.org/viewvc/llvm-project?rev=206780&view=rev
Log:
Use value semantics to manage DbgVariables rather than dynamic allocation/pointers.
Requires switching some vectors to lists to maintain pointer validity.
These could be changed to forward_lists (singly linked) with a bit more
work - I've left comments to that effect.
Modified:
llvm/trunk/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
llvm/trunk/lib/CodeGen/AsmPrinter/DwarfDebug.h
Modified: llvm/trunk/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/AsmPrinter/DwarfDebug.cpp?rev=206780&r1=206779&r2=206780&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/AsmPrinter/DwarfDebug.cpp (original)
+++ llvm/trunk/lib/CodeGen/AsmPrinter/DwarfDebug.cpp Mon Apr 21 15:13:09 2014
@@ -563,14 +563,13 @@ DIE *DwarfDebug::createScopeChildrenDIE(
// Collect arguments for current function.
if (LScopes.isCurrentFunctionScope(Scope)) {
- for (DbgVariable *ArgDV : CurrentFnArguments)
- if (ArgDV)
- if (DIE *Arg =
- TheCU->constructVariableDIE(*ArgDV, Scope->isAbstractScope())) {
- Children.push_back(Arg);
- if (ArgDV->isObjectPointer())
- ObjectPointer = Arg;
- }
+ for (DbgVariable &ArgDV : CurrentFnArguments)
+ if (ArgDV.getVariable()) {
+ DIE *Arg = TheCU->constructVariableDIE(ArgDV, Scope->isAbstractScope());
+ Children.push_back(Arg);
+ if (ArgDV.isObjectPointer())
+ ObjectPointer = Arg;
+ }
// If this is a variadic function, add an unspecified parameter.
DISubprogram SP(Scope->getScopeNode());
@@ -583,11 +582,11 @@ DIE *DwarfDebug::createScopeChildrenDIE(
}
// Collect lexical scope children first.
- for (DbgVariable *DV : ScopeVariables.lookup(Scope))
- if (DIE *Variable = TheCU->constructVariableDIE(*DV,
+ for (DbgVariable &DV : ScopeVariables.lookup(Scope))
+ if (DIE *Variable = TheCU->constructVariableDIE(DV,
Scope->isAbstractScope())) {
Children.push_back(Variable);
- if (DV->isObjectPointer())
+ if (DV.isObjectPointer())
ObjectPointer = Variable;
}
for (LexicalScope *LS : Scope->getChildren())
@@ -1120,32 +1119,33 @@ DbgVariable *DwarfDebug::findAbstractVar
if (!Scope)
return NULL;
- AbsDbgVariable = new DbgVariable(Var, NULL, this);
- addScopeVariable(Scope, AbsDbgVariable);
+ AbsDbgVariable = &addScopeVariable(Scope, DbgVariable(Var, NULL, this));
AbstractVariables[Var] = AbsDbgVariable;
return AbsDbgVariable;
}
// If Var is a current function argument then add it to CurrentFnArguments list.
-bool DwarfDebug::addCurrentFnArgument(DbgVariable *Var, LexicalScope *Scope) {
+DbgVariable *DwarfDebug::addCurrentFnArgument(DbgVariable &Var, LexicalScope *Scope) {
if (!LScopes.isCurrentFunctionScope(Scope))
- return false;
- DIVariable DV = Var->getVariable();
+ return nullptr;
+ DIVariable DV = Var.getVariable();
if (DV.getTag() != dwarf::DW_TAG_arg_variable)
- return false;
+ return nullptr;
unsigned ArgNo = DV.getArgNumber();
if (ArgNo == 0)
- return false;
+ return nullptr;
- size_t Size = CurrentFnArguments.size();
- if (Size == 0)
- CurrentFnArguments.resize(CurFn->getFunction()->arg_size());
- // llvm::Function argument size is not good indicator of how many
- // arguments does the function have at source level.
- if (ArgNo > Size)
- CurrentFnArguments.resize(ArgNo * 2);
- CurrentFnArguments[ArgNo - 1] = Var;
- return true;
+ auto I = CurrentFnArguments.begin();
+ for (; I != CurrentFnArguments.end(); ++I)
+ if (ArgNo < I->getVariable().getArgNumber())
+ break;
+ return &*CurrentFnArguments.insert(I, std::move(Var));
+}
+
+DbgVariable &DwarfDebug::addVariable(DbgVariable Var, LexicalScope *Scope) {
+ if (DbgVariable *Res = addCurrentFnArgument(Var, Scope))
+ return *Res;
+ return addScopeVariable(Scope, std::move(Var));
}
// Collect variable information from side table maintained by MMI.
@@ -1163,10 +1163,9 @@ void DwarfDebug::collectVariableInfoFrom
continue;
DbgVariable *AbsDbgVariable = findAbstractVariable(DV, VI.Loc);
- DbgVariable *RegVar = new DbgVariable(DV, AbsDbgVariable, this);
- RegVar->setFrameIndex(VI.Slot);
- if (!addCurrentFnArgument(RegVar, Scope))
- addScopeVariable(Scope, RegVar);
+ DbgVariable RegVar(DV, AbsDbgVariable, this);
+ RegVar.setFrameIndex(VI.Slot);
+ addVariable(std::move(RegVar), Scope);
if (AbsDbgVariable)
AbsDbgVariable->setFrameIndex(VI.Slot);
}
@@ -1247,21 +1246,19 @@ DwarfDebug::collectVariableInfo(SmallPtr
Processed.insert(DV);
assert(MInsn->isDebugValue() && "History must begin with debug value");
DbgVariable *AbsVar = findAbstractVariable(DV, MInsn->getDebugLoc());
- DbgVariable *RegVar = new DbgVariable(DV, AbsVar, this);
- if (!addCurrentFnArgument(RegVar, Scope))
- addScopeVariable(Scope, RegVar);
+ DbgVariable &RegVar = addVariable(DbgVariable(DV, AbsVar, this), Scope);
if (AbsVar)
AbsVar->setMInsn(MInsn);
// Simplify ranges that are fully coalesced.
if (History.size() <= 1 ||
(History.size() == 2 && MInsn->isIdenticalTo(History.back()))) {
- RegVar->setMInsn(MInsn);
+ RegVar.setMInsn(MInsn);
continue;
}
// Handle multiple DBG_VALUE instructions describing one variable.
- RegVar->setDotDebugLocOffset(DotDebugLocEntries.size());
+ RegVar.setDotDebugLocOffset(DotDebugLocEntries.size());
DotDebugLocEntries.resize(DotDebugLocEntries.size() + 1);
DebugLocList &LocList = DotDebugLocEntries.back();
@@ -1319,7 +1316,7 @@ DwarfDebug::collectVariableInfo(SmallPtr
if (!DV || !DV.isVariable() || !Processed.insert(DV))
continue;
if (LexicalScope *Scope = LScopes.findLexicalScope(DV.getContext()))
- addScopeVariable(Scope, new DbgVariable(DV, NULL, this));
+ addScopeVariable(Scope, DbgVariable(DV, NULL, this));
}
}
@@ -1626,9 +1623,9 @@ void DwarfDebug::beginFunction(const Mac
}
}
-void DwarfDebug::addScopeVariable(LexicalScope *LS, DbgVariable *Var) {
- SmallVectorImpl<DbgVariable *> &Vars = ScopeVariables[LS];
- DIVariable DV = Var->getVariable();
+DbgVariable &DwarfDebug::addScopeVariable(LexicalScope *LS, DbgVariable Var) {
+ auto &Vars = ScopeVariables[LS];
+ DIVariable DV = Var.getVariable();
// Variables with positive arg numbers are parameters.
if (unsigned ArgNum = DV.getArgNumber()) {
// Keep all parameters in order at the start of the variable list to ensure
@@ -1638,9 +1635,9 @@ void DwarfDebug::addScopeVariable(Lexica
// builds have the right order to begin with), searching from the back (this
// would catch the unoptimized case quickly), or doing a binary search
// rather than linear search.
- SmallVectorImpl<DbgVariable *>::iterator I = Vars.begin();
+ auto I = Vars.begin();
while (I != Vars.end()) {
- unsigned CurNum = (*I)->getVariable().getArgNumber();
+ unsigned CurNum = I->getVariable().getArgNumber();
// A local (non-parameter) variable has been found, insert immediately
// before it.
if (CurNum == 0)
@@ -1650,11 +1647,11 @@ void DwarfDebug::addScopeVariable(Lexica
break;
++I;
}
- Vars.insert(I, Var);
- return;
+ return *Vars.insert(I, std::move(Var));
}
- Vars.push_back(Var);
+ Vars.push_back(std::move(Var));
+ return Vars.back();
}
// Gather and emit post-function debug information.
@@ -1710,7 +1707,7 @@ void DwarfDebug::endFunction(const Machi
if (AbstractVariables.lookup(CleanDV))
continue;
if (LexicalScope *Scope = LScopes.findAbstractScope(DV.getContext()))
- addScopeVariable(Scope, new DbgVariable(DV, NULL, this));
+ addScopeVariable(Scope, DbgVariable(DV, NULL, this));
}
}
if (ProcessedSPNodes.count(AScope->getScopeNode()) == 0)
@@ -1728,10 +1725,8 @@ void DwarfDebug::endFunction(const Machi
PrevCU = TheCU;
// Clear debug info
- for (auto &I : ScopeVariables)
- DeleteContainerPointers(I.second);
ScopeVariables.clear();
- DeleteContainerPointers(CurrentFnArguments);
+ CurrentFnArguments.clear();
UserVariables.clear();
DbgValues.clear();
AbstractVariables.clear();
@@ -2470,7 +2465,7 @@ void DwarfDebug::emitDebugARanges() {
// Build a set of address spans, sorted by CU.
for (const MCSection *Section : Sections) {
- SmallVector<SymbolCU, 8> &List = SectionMap[Section];
+ auto &List = SectionMap[Section];
if (List.size() < 2)
continue;
Modified: llvm/trunk/lib/CodeGen/AsmPrinter/DwarfDebug.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/AsmPrinter/DwarfDebug.h?rev=206780&r1=206779&r2=206780&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/AsmPrinter/DwarfDebug.h (original)
+++ llvm/trunk/lib/CodeGen/AsmPrinter/DwarfDebug.h Mon Apr 21 15:13:09 2014
@@ -30,6 +30,8 @@
#include "llvm/MC/MCDwarf.h"
#include "llvm/Support/Allocator.h"
+#include <list>
+
namespace llvm {
class AsmPrinter;
@@ -274,7 +276,9 @@ class DwarfDebug : public AsmPrinterHand
SectionMapType SectionMap;
// List of arguments for current function.
- SmallVector<DbgVariable *, 8> CurrentFnArguments;
+ // Linked list use to maintain pointer validity. Singly linked list could
+ // suffice with some contortions to addCurrentFnArgument.
+ std::list<DbgVariable> CurrentFnArguments;
LexicalScopes LScopes;
@@ -282,7 +286,9 @@ class DwarfDebug : public AsmPrinterHand
DenseMap<const MDNode *, DIE *> AbstractSPDies;
// Collection of dbg variables of a scope.
- typedef DenseMap<LexicalScope *, SmallVector<DbgVariable *, 8> >
+ // Linked list use to maintain pointer validity. Singly linked list could
+ // suffice with some contortions to addScopeVariable.
+ typedef DenseMap<LexicalScope *, std::list<DbgVariable>>
ScopeVariablesMap;
ScopeVariablesMap ScopeVariables;
@@ -413,7 +419,7 @@ class DwarfDebug : public AsmPrinterHand
MCDwarfDwoLineTable *getDwoLineTable(const DwarfCompileUnit &);
- void addScopeVariable(LexicalScope *LS, DbgVariable *Var);
+ DbgVariable &addScopeVariable(LexicalScope *LS, DbgVariable Var);
const SmallVectorImpl<DwarfUnit *> &getUnits() {
return InfoHolder.getUnits();
@@ -591,7 +597,9 @@ class DwarfDebug : public AsmPrinterHand
/// \brief If Var is an current function argument that add it in
/// CurrentFnArguments list.
- bool addCurrentFnArgument(DbgVariable *Var, LexicalScope *Scope);
+ DbgVariable *addCurrentFnArgument(DbgVariable &Var, LexicalScope *Scope);
+
+ DbgVariable &addVariable(DbgVariable Var, LexicalScope *Scope);
/// \brief Populate LexicalScope entries with variables' info.
void collectVariableInfo(SmallPtrSet<const MDNode *, 16> &ProcessedVars);
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