From 62e0f454a03d4989c1646563ba2e8d87c5753964 Mon Sep 17 00:00:00 2001 From: "Duncan P. N. Exon Smith" Date: Wed, 15 Apr 2015 22:29:27 +0000 Subject: DebugInfo: Remove 'inlinedAt:' field from MDLocalVariable Remove 'inlinedAt:' from MDLocalVariable. Besides saving some memory (variables with it seem to be single largest `Metadata` contributer to memory usage right now in -g -flto builds), this stops optimization and backend passes from having to change local variables. The 'inlinedAt:' field was used by the backend in two ways: 1. To tell the backend whether and into what a variable was inlined. 2. To create a unique id for each inlined variable. Instead, rely on the 'inlinedAt:' field of the intrinsic's `!dbg` attachment, and change the DWARF backend to use a typedef called `InlinedVariable` which is `std::pair`. This `DebugLoc` is already passed reliably through the backend (as verified by r234021). This commit removes the check from r234021, but I added a new check (that will survive) in r235048, and changed the `DIBuilder` API in r235041 to require a `!dbg` attachment whose 'scope:` is in the same `MDSubprogram` as the variable's. If this breaks your out-of-tree testcases, perhaps the script I used (mdlocalvariable-drop-inlinedat.sh) will help; I'll attach it to PR22778 in a moment. llvm-svn: 235050 --- llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp | 80 +++++++++++++++--------------- 1 file changed, 40 insertions(+), 40 deletions(-) (limited to 'llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp') diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp index 527c1af88f8..631d13167bd 100644 --- a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp +++ b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp @@ -489,7 +489,8 @@ void DwarfDebug::finishVariableDefinitions() { // DIE::getUnit isn't simple - it walks parent pointers, etc. DwarfCompileUnit *Unit = lookupUnit(VariableDie->getUnit()); assert(Unit); - DbgVariable *AbsVar = getExistingAbstractVariable(Var->getVariable()); + DbgVariable *AbsVar = getExistingAbstractVariable( + InlinedVariable(Var->getVariable(), Var->getInlinedAt())); if (AbsVar && AbsVar->getDIE()) { Unit->addDIEEntry(*VariableDie, dwarf::DW_AT_abstract_origin, *AbsVar->getDIE()); @@ -660,48 +661,43 @@ void DwarfDebug::endModule() { } // Find abstract variable, if any, associated with Var. -DbgVariable *DwarfDebug::getExistingAbstractVariable(const DIVariable &DV, +DbgVariable *DwarfDebug::getExistingAbstractVariable(InlinedVariable IV, DIVariable &Cleansed) { - LLVMContext &Ctx = DV->getContext(); // More then one inlined variable corresponds to one abstract variable. - // FIXME: This duplication of variables when inlining should probably be - // removed. It's done to allow each DIVariable to describe its location - // because the DebugLoc on the dbg.value/declare isn't accurate. We should - // make it accurate then remove this duplication/cleansing stuff. - Cleansed = cleanseInlinedVariable(DV, Ctx); + Cleansed = IV.first; auto I = AbstractVariables.find(Cleansed); if (I != AbstractVariables.end()) return I->second.get(); return nullptr; } -DbgVariable *DwarfDebug::getExistingAbstractVariable(const DIVariable &DV) { +DbgVariable *DwarfDebug::getExistingAbstractVariable(InlinedVariable IV) { DIVariable Cleansed; - return getExistingAbstractVariable(DV, Cleansed); + return getExistingAbstractVariable(IV, Cleansed); } void DwarfDebug::createAbstractVariable(const DIVariable &Var, LexicalScope *Scope) { - auto AbsDbgVariable = make_unique(Var, DIExpression(), this); + auto AbsDbgVariable = + make_unique(Var, nullptr, DIExpression(), this); InfoHolder.addScopeVariable(Scope, AbsDbgVariable.get()); AbstractVariables[Var] = std::move(AbsDbgVariable); } -void DwarfDebug::ensureAbstractVariableIsCreated(const DIVariable &DV, +void DwarfDebug::ensureAbstractVariableIsCreated(InlinedVariable IV, const MDNode *ScopeNode) { - DIVariable Cleansed = DV; - if (getExistingAbstractVariable(DV, Cleansed)) + DIVariable Cleansed; + if (getExistingAbstractVariable(IV, Cleansed)) return; createAbstractVariable(Cleansed, LScopes.getOrCreateAbstractScope( cast(ScopeNode))); } -void -DwarfDebug::ensureAbstractVariableIsCreatedIfScoped(const DIVariable &DV, - const MDNode *ScopeNode) { - DIVariable Cleansed = DV; - if (getExistingAbstractVariable(DV, Cleansed)) +void DwarfDebug::ensureAbstractVariableIsCreatedIfScoped( + InlinedVariable IV, const MDNode *ScopeNode) { + DIVariable Cleansed; + if (getExistingAbstractVariable(IV, Cleansed)) return; if (LexicalScope *Scope = @@ -711,11 +707,12 @@ DwarfDebug::ensureAbstractVariableIsCreatedIfScoped(const DIVariable &DV, // Collect variable information from side table maintained by MMI. void DwarfDebug::collectVariableInfoFromMMITable( - SmallPtrSetImpl &Processed) { + DenseSet &Processed) { for (const auto &VI : MMI->getVariableDbgInfo()) { if (!VI.Var) continue; - Processed.insert(VI.Var); + InlinedVariable Var(VI.Var, VI.Loc ? VI.Loc->getInlinedAt() : nullptr); + Processed.insert(Var); LexicalScope *Scope = LScopes.findLexicalScope(VI.Loc); // If variable scope is not found then skip this variable. @@ -726,8 +723,9 @@ void DwarfDebug::collectVariableInfoFromMMITable( assert(DV->isValidLocationForIntrinsic(VI.Loc) && "Expected inlined-at fields to agree"); DIExpression Expr = cast_or_null(VI.Expr); - ensureAbstractVariableIsCreatedIfScoped(DV, Scope->getScopeNode()); - auto RegVar = make_unique(DV, Expr, this, VI.Slot); + ensureAbstractVariableIsCreatedIfScoped(Var, Scope->getScopeNode()); + auto RegVar = + make_unique(Var.first, Var.second, Expr, this, VI.Slot); if (InfoHolder.addScopeVariable(Scope, RegVar.get())) ConcreteVariables.push_back(std::move(RegVar)); } @@ -877,35 +875,34 @@ DwarfDebug::buildLocationList(SmallVectorImpl &DebugLoc, // Find variables for each lexical scope. -void -DwarfDebug::collectVariableInfo(DwarfCompileUnit &TheCU, DISubprogram SP, - SmallPtrSetImpl &Processed) { +void DwarfDebug::collectVariableInfo(DwarfCompileUnit &TheCU, DISubprogram SP, + DenseSet &Processed) { // Grab the variable info that was squirreled away in the MMI side-table. collectVariableInfoFromMMITable(Processed); for (const auto &I : DbgValues) { - DIVariable DV = cast(I.first); - if (Processed.count(DV)) + InlinedVariable IV = I.first; + if (Processed.count(IV)) continue; - // Instruction ranges, specifying where DV is accessible. + // Instruction ranges, specifying where IV is accessible. const auto &Ranges = I.second; if (Ranges.empty()) continue; LexicalScope *Scope = nullptr; - if (MDLocation *IA = DV->getInlinedAt()) - Scope = LScopes.findInlinedScope(DV->getScope(), IA); + if (const MDLocation *IA = IV.second) + Scope = LScopes.findInlinedScope(IV.first->getScope(), IA); else - Scope = LScopes.findLexicalScope(DV->getScope()); + Scope = LScopes.findLexicalScope(IV.first->getScope()); // If variable scope is not found then skip this variable. if (!Scope) continue; - Processed.insert(DV); + Processed.insert(IV); const MachineInstr *MInsn = Ranges.front().first; assert(MInsn->isDebugValue() && "History must begin with debug value"); - ensureAbstractVariableIsCreatedIfScoped(DV, Scope->getScopeNode()); + ensureAbstractVariableIsCreatedIfScoped(IV, Scope->getScopeNode()); ConcreteVariables.push_back(make_unique(MInsn, this)); DbgVariable *RegVar = ConcreteVariables.back().get(); InfoHolder.addScopeVariable(Scope, RegVar); @@ -931,12 +928,14 @@ DwarfDebug::collectVariableInfo(DwarfCompileUnit &TheCU, DISubprogram SP, // Collect info for variables that were optimized out. for (DIVariable DV : SP->getVariables()) { - if (!Processed.insert(DV).second) + if (!Processed.insert(InlinedVariable(DV, nullptr)).second) continue; if (LexicalScope *Scope = LScopes.findLexicalScope(DV->getScope())) { - ensureAbstractVariableIsCreatedIfScoped(DV, Scope->getScopeNode()); + ensureAbstractVariableIsCreatedIfScoped(InlinedVariable(DV, nullptr), + Scope->getScopeNode()); DIExpression NoExpr; - ConcreteVariables.push_back(make_unique(DV, NoExpr, this)); + ConcreteVariables.push_back( + make_unique(DV, nullptr, NoExpr, this)); InfoHolder.addScopeVariable(Scope, ConcreteVariables.back().get()); } } @@ -1188,7 +1187,7 @@ void DwarfDebug::endFunction(const MachineFunction *MF) { DISubprogram SP = cast(FnScope->getScopeNode()); DwarfCompileUnit &TheCU = *SPMap.lookup(SP); - SmallPtrSet ProcessedVars; + DenseSet ProcessedVars; collectVariableInfo(TheCU, SP, ProcessedVars); // Add the range of this function to the list of ranges for the CU. @@ -1218,9 +1217,10 @@ void DwarfDebug::endFunction(const MachineFunction *MF) { DISubprogram SP = cast(AScope->getScopeNode()); // Collect info for variables that were optimized out. for (DIVariable DV : SP->getVariables()) { - if (!ProcessedVars.insert(DV).second) + if (!ProcessedVars.insert(InlinedVariable(DV, nullptr)).second) continue; - ensureAbstractVariableIsCreated(DV, DV->getScope()); + ensureAbstractVariableIsCreated(InlinedVariable(DV, nullptr), + DV->getScope()); assert(LScopes.getAbstractScopesList().size() == NumAbstractScopes && "ensureAbstractVariableIsCreated inserted abstract scopes"); } -- cgit v1.2.3