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view gen/todebug.cpp @ 1117:4c20fcc4252b
Fun with parameter attributes: For several of the "synthetic" parameters added
to D functions, we can apply noalias and nocapture. They are sret parameters,
'nest' pointers passed to nested functions, and _argptr:
Nocapture:
- Sret and nest are nocapture because they don't represent D-level variables,
and thus the callee can't (validly) obtain a pointer to them, let alone keep
it around after it returns.
- _argptr is nocapture because although the callee has access to it as a
pointer, that pointer is invalidated when it returns.
All three are noalias because they're function-local variables
- Sret and _argptr are noalias because they're freshly alloca'd memory only
used for a single function call that's not allowed to keep an aliasing
pointer to it around (since the parameter is nocapture).
- 'Nest' is noalias because the callee only ever has access to one such pointer
per parent function, and every parent function has a different one.
This commit also ensures attributes set on sret, _arguments and _argptr are
propagated to calls to such functions.
It also adds one exception to the general rule that attributes on function types
should propagate to calls: the type of a delegate's function pointer has a
'nest' parameter, but this can either be a true 'nest' (for delegates to nested
functions) or a 'this' (for delegates to member functions). Since 'this' is
neither noalias nor nocapture, and there's generally no way to tell which one it
is, we remove these attributes at the call site if the callee is a delegate.
author | Frits van Bommel <fvbommel wxs.nl> |
---|---|
date | Sat, 14 Mar 2009 22:15:31 +0100 |
parents | 8038b106c458 |
children | 79758fd2f48a |
line wrap: on
line source
#include "gen/llvm.h" #include "llvm/Support/Dwarf.h" #include "llvm/CodeGen/MachineModuleInfo.h" #include "llvm/System/Path.h" #include "declaration.h" #include "module.h" #include "mars.h" #include "gen/todebug.h" #include "gen/irstate.h" #include "gen/tollvm.h" #include "gen/logger.h" #include "gen/llvmhelpers.h" #include "gen/linkage.h" #include "ir/irmodule.h" using namespace llvm::dwarf; #define DBG_NULL ( LLConstant::getNullValue(DBG_TYPE) ) #define DBG_TYPE ( getPtrToType(llvm::StructType::get(NULL,NULL)) ) #define DBG_CAST(X) ( llvm::ConstantExpr::getBitCast(X, DBG_TYPE) ) #define DBG_TAG(X) ( llvm::ConstantExpr::getAdd( DtoConstUint( X ), DtoConstUint( llvm::LLVMDebugVersion ) ) ) ////////////////////////////////////////////////////////////////////////////////////////////////// /** * Emits a global variable, LLVM Dwarf style, only declares. * @param type Type of variable. * @param name Name. * @return The global variable. */ static LLGlobalVariable* emitDwarfGlobalDecl(const LLStructType* type, const char* name, bool linkonce=false) { LLGlobalValue::LinkageTypes linkage = linkonce ? DEBUGINFO_LINKONCE_LINKAGE_TYPE : LLGlobalValue::InternalLinkage; LLGlobalVariable* gv = new LLGlobalVariable(type, true, linkage, NULL, name, gIR->module); gv->setSection("llvm.metadata"); return gv; } ////////////////////////////////////////////////////////////////////////////////////////////////// static llvm::DIAnchor getDwarfAnchor(dwarf_constants c) { switch (c) { case DW_TAG_compile_unit: return gIR->difactory.GetOrCreateCompileUnitAnchor(); case DW_TAG_variable: return gIR->difactory.GetOrCreateGlobalVariableAnchor(); case DW_TAG_subprogram: return gIR->difactory.GetOrCreateSubprogramAnchor(); default: assert(0); } } ////////////////////////////////////////////////////////////////////////////////////////////////// static const llvm::StructType* getDwarfCompileUnitType() { return isaStruct(gIR->module->getTypeByName("llvm.dbg.compile_unit.type")); } static const llvm::StructType* getDwarfSubProgramType() { return isaStruct(gIR->module->getTypeByName("llvm.dbg.subprogram.type")); } static const llvm::StructType* getDwarfVariableType() { return isaStruct(gIR->module->getTypeByName("llvm.dbg.variable.type")); } static const llvm::StructType* getDwarfDerivedTypeType() { return isaStruct(gIR->module->getTypeByName("llvm.dbg.derivedtype.type")); } static const llvm::StructType* getDwarfBasicTypeType() { return isaStruct(gIR->module->getTypeByName("llvm.dbg.basictype.type")); } static const llvm::StructType* getDwarfCompositeTypeType() { return isaStruct(gIR->module->getTypeByName("llvm.dbg.compositetype.type")); } static const llvm::StructType* getDwarfGlobalVariableType() { return isaStruct(gIR->module->getTypeByName("llvm.dbg.global_variable.type")); } ////////////////////////////////////////////////////////////////////////////////////////////////// // get the module the symbol is in, or - for template instances - the current module static Module* getDefinedModule(Dsymbol* s) { if (!DtoIsTemplateInstance(s)) return s->getModule(); else return gIR->dmodule; } ////////////////////////////////////////////////////////////////////////////////////////////////// static llvm::DIType dwarfTypeDescription_impl(Type* type, llvm::DICompileUnit cu, const char* c_name); static llvm::DIType dwarfTypeDescription(Type* type, llvm::DICompileUnit cu, const char* c_name); ////////////////////////////////////////////////////////////////////////////////////////////////// static llvm::DIBasicType dwarfBasicType(Type* type, llvm::DICompileUnit compileUnit) { Type* t = type->toBasetype(); const LLType* T = DtoType(type); // find encoding unsigned id; if (t->isintegral()) { if (type->isunsigned()) id = DW_ATE_unsigned; else id = DW_ATE_signed; } else if (t->isfloating()) { id = DW_ATE_float; } else { assert(0 && "unsupported basictype for debug info"); } return gIR->difactory.CreateBasicType( compileUnit, // context type->toChars(), // name llvm::DICompileUnit(NULL), // compile unit 0, // line number getTypeBitSize(T), // size (bits) getABITypeAlign(T)*8, // align (bits) 0, // offset (bits) //FIXME: need flags? 0, // flags id // encoding ); } ////////////////////////////////////////////////////////////////////////////////////////////////// static llvm::DIDerivedType dwarfDerivedType(Type* type, llvm::DICompileUnit compileUnit) { const LLType* T = DtoType(type); Type* t = type->toBasetype(); assert(t->ty == Tpointer && "unsupported derivedtype for debug info, only pointers allowed"); // find base type llvm::DIType basetype; Type* nt = t->nextOf(); basetype = dwarfTypeDescription_impl(nt, compileUnit, NULL); if (nt->ty == Tvoid) basetype = llvm::DIType(NULL); return gIR->difactory.CreateDerivedType( DW_TAG_pointer_type, // tag compileUnit, // context "", // name llvm::DICompileUnit(NULL), // compile unit 0, // line number getTypeBitSize(T), // size (bits) getABITypeAlign(T)*8, // align (bits) 0, // offset (bits) //FIXME: need flags? 0, // flags basetype // derived from ); } ////////////////////////////////////////////////////////////////////////////////////////////////// static llvm::DIDerivedType dwarfMemberType(unsigned linnum, Type* type, llvm::DICompileUnit compileUnit, llvm::DICompileUnit definedCU, const char* c_name, unsigned offset) { const LLType* T = DtoType(type); Type* t = type->toBasetype(); // find base type llvm::DIType basetype; basetype = dwarfTypeDescription(t, compileUnit, NULL); if (t->ty == Tvoid) basetype = llvm::DIType(NULL); return gIR->difactory.CreateDerivedType( DW_TAG_member, // tag compileUnit, // context c_name, // name definedCU, // compile unit linnum, // line number getTypeBitSize(T), // size (bits) getABITypeAlign(T)*8, // align (bits) offset*8, // offset (bits) //FIXME: need flags? 0, // flags basetype // derived from ); } ////////////////////////////////////////////////////////////////////////////////////////////////// //FIXME: This does not use llvm's DIFactory as it can't // handle recursive types properly. static llvm::DICompositeType dwarfCompositeType(Type* type, llvm::DICompileUnit compileUnit) { const LLType* T = DtoType(type); Type* t = type->toBasetype(); // defaults LLConstant* name = getNullPtr(getVoidPtrType()); LLGlobalVariable* members = NULL; unsigned linnum = 0; llvm::DICompileUnit definedCU; // prepare tag and members unsigned tag; // declare final global variable LLGlobalVariable* gv = NULL; // dynamic array if (t->ty == Tarray) { tag = DW_TAG_structure_type; LLGlobalVariable* len = dwarfMemberType(0, Type::tsize_t, compileUnit, llvm::DICompileUnit(NULL), "length", 0).getGV(); assert(len); LLGlobalVariable* ptr = dwarfMemberType(0, t->nextOf()->pointerTo(), compileUnit, llvm::DICompileUnit(NULL), "ptr", global.params.is64bit?8:4).getGV(); assert(ptr); const LLArrayType* at = LLArrayType::get(DBG_TYPE, 2); std::vector<LLConstant*> elems(2); elems[0] = DBG_CAST(len); elems[1] = DBG_CAST(ptr); LLConstant* ca = LLConstantArray::get(at, elems); members = new LLGlobalVariable(ca->getType(), true, LLGlobalValue::InternalLinkage, ca, ".array", gIR->module); members->setSection("llvm.metadata"); name = DtoConstStringPtr(t->toChars(), "llvm.metadata"); } // struct/class else if (t->ty == Tstruct || t->ty == Tclass) { AggregateDeclaration* sd; if (t->ty == Tstruct) { TypeStruct* ts = (TypeStruct*)t; sd = ts->sym; } else { TypeClass* tc = (TypeClass*)t; sd = tc->sym; } assert(sd); // if we don't know the aggregate's size, we don't know enough about it // to provide debug info. probably a forward-declared struct? if (sd->sizeok == 0) return llvm::DICompositeType(NULL); IrStruct* ir = sd->ir.irStruct; assert(ir); if (!ir->diCompositeType.isNull()) return ir->diCompositeType; // set to handle recursive types properly gv = emitDwarfGlobalDecl(getDwarfCompositeTypeType(), "llvm.dbg.compositetype"); // set bogus initializer to satisfy asserts in DICompositeType constructor gv->setInitializer(LLConstant::getNullValue(getDwarfCompositeTypeType())); ir->diCompositeType = llvm::DICompositeType(gv); tag = DW_TAG_structure_type; name = DtoConstStringPtr(sd->toChars(), "llvm.metadata"); linnum = sd->loc.linnum; definedCU = DtoDwarfCompileUnit(getDefinedModule(sd)); std::vector<LLConstant*> elems; if (!ir->aggrdecl->isInterfaceDeclaration()) // plain interfaces don't have one { std::vector<VarDeclaration*>& arr = ir->varDecls; size_t narr = arr.size(); elems.reserve(narr); for (int k=0; k<narr; k++) { VarDeclaration* vd = arr[k]; assert(vd); LLGlobalVariable* ptr = dwarfMemberType(vd->loc.linnum, vd->type, compileUnit, definedCU, vd->toChars(), vd->offset).getGV(); elems.push_back(DBG_CAST(ptr)); } } const LLArrayType* at = LLArrayType::get(DBG_TYPE, elems.size()); LLConstant* ca = LLConstantArray::get(at, elems); members = new LLGlobalVariable(ca->getType(), true, LLGlobalValue::InternalLinkage, ca, ".array", gIR->module); members->setSection("llvm.metadata"); } // unsupported composite type else { assert(0 && "unsupported compositetype for debug info"); } std::vector<LLConstant*> vals(11); // tag vals[0] = DBG_TAG(tag); // context vals[1] = DBG_CAST(compileUnit.getGV()); // name vals[2] = name; // compile unit where defined if (definedCU.getGV()) vals[3] = DBG_CAST(definedCU.getGV()); else vals[3] = DBG_NULL; // line number where defined vals[4] = DtoConstInt(linnum); // size in bits vals[5] = LLConstantInt::get(LLType::Int64Ty, getTypeBitSize(T), false); // alignment in bits vals[6] = LLConstantInt::get(LLType::Int64Ty, getABITypeAlign(T)*8, false); // offset in bits vals[7] = LLConstantInt::get(LLType::Int64Ty, 0, false); // FIXME: dont know what this is vals[8] = DtoConstUint(0); // FIXME: ditto vals[9] = DBG_NULL; // members array if (members) vals[10] = DBG_CAST(members); else vals[10] = DBG_NULL; // set initializer if (!gv) gv = emitDwarfGlobalDecl(getDwarfCompositeTypeType(), "llvm.dbg.compositetype"); LLConstant* initia = LLConstantStruct::get(getDwarfCompositeTypeType(), vals); gv->setInitializer(initia); return llvm::DICompositeType(gv); } ////////////////////////////////////////////////////////////////////////////////////////////////// static llvm::DIGlobalVariable dwarfGlobalVariable(LLGlobalVariable* ll, VarDeclaration* vd) { #if DMDV2 assert(vd->isDataseg() || (vd->storage_class & (STCconst | STCinvariant) && vd->init)); #else assert(vd->isDataseg()); #endif llvm::DICompileUnit compileUnit = DtoDwarfCompileUnit(gIR->dmodule); return gIR->difactory.CreateGlobalVariable( compileUnit, // context vd->mangle(), // name vd->toPrettyChars(), // displayname vd->toChars(), // linkage name DtoDwarfCompileUnit(getDefinedModule(vd)), // compile unit vd->loc.linnum, // line num dwarfTypeDescription_impl(vd->type, compileUnit, NULL), // type vd->protection == PROTprivate, // is local to unit getDefinedModule(vd) == gIR->dmodule, // is definition ll // value ); } ////////////////////////////////////////////////////////////////////////////////////////////////// static llvm::DIVariable dwarfVariable(VarDeclaration* vd, llvm::DIType type) { assert(!vd->isDataseg() && "static variable"); unsigned tag; if (vd->isParameter()) tag = DW_TAG_arg_variable; else tag = DW_TAG_auto_variable; return gIR->difactory.CreateVariable( tag, // tag gIR->func()->diSubprogram, // context vd->toChars(), // name DtoDwarfCompileUnit(getDefinedModule(vd)), // compile unit vd->loc.linnum, // line num type // type ); } ////////////////////////////////////////////////////////////////////////////////////////////////// static void dwarfDeclare(LLValue* var, llvm::DIVariable divar) { gIR->difactory.InsertDeclare(var, divar, gIR->scopebb()); } ////////////////////////////////////////////////////////////////////////////////////////////////// static llvm::DIType dwarfTypeDescription_impl(Type* type, llvm::DICompileUnit cu, const char* c_name) { Type* t = type->toBasetype(); if (t->ty == Tvoid) return llvm::DIType(NULL); else if (t->isintegral() || t->isfloating()) return dwarfBasicType(type, cu); else if (t->ty == Tpointer) return dwarfDerivedType(type, cu); else if (t->ty == Tarray || t->ty == Tstruct || t->ty == Tclass) return dwarfCompositeType(type, cu); return llvm::DIType(NULL); } static llvm::DIType dwarfTypeDescription(Type* type, llvm::DICompileUnit cu, const char* c_name) { Type* t = type->toBasetype(); if (t->ty == Tclass) return dwarfTypeDescription_impl(type->pointerTo(), cu, c_name); else return dwarfTypeDescription_impl(type, cu, c_name); } ////////////////////////////////////////////////////////////////////////////////////////////////// void DtoDwarfLocalVariable(LLValue* ll, VarDeclaration* vd) { Logger::println("D to dwarf local variable"); LOG_SCOPE; // get compile units llvm::DICompileUnit thisCU = DtoDwarfCompileUnit(gIR->dmodule); llvm::DICompileUnit varCU = DtoDwarfCompileUnit(getDefinedModule(vd)); // get type description llvm::DIType TD = dwarfTypeDescription(vd->type, thisCU, NULL); if (TD.isNull()) return; // unsupported // get variable description llvm::DIVariable VD = dwarfVariable(vd, TD); // declare dwarfDeclare(ll, VD); } ////////////////////////////////////////////////////////////////////////////////////////////////// llvm::DICompileUnit DtoDwarfCompileUnit(Module* m) { Logger::println("D to dwarf compile_unit"); LOG_SCOPE; // we might be generating for an import if (!m->ir.irModule) m->ir.irModule = new IrModule(m, m->srcfile->toChars()); else if (!m->ir.irModule->diCompileUnit.isNull()) { assert (m->ir.irModule->diCompileUnit.getGV()->getParent() == gIR->module && "debug info compile unit belongs to incorrect llvm module!"); return m->ir.irModule->diCompileUnit; } // prepare srcpath std::string srcpath(FileName::path(m->srcfile->name->toChars())); if (!FileName::absolute(srcpath.c_str())) { llvm::sys::Path tmp = llvm::sys::Path::GetCurrentDirectory(); tmp.appendComponent(srcpath); srcpath = tmp.toString(); if (!srcpath.empty() && *srcpath.rbegin() != '/' && *srcpath.rbegin() != '\\') srcpath = srcpath + '/'; } // make compile unit m->ir.irModule->diCompileUnit = gIR->difactory.CreateCompileUnit( global.params.symdebug == 2 ? DW_LANG_C : DW_LANG_D, m->srcfile->name->toChars(), srcpath, "LDC (http://www.dsource.org/projects/ldc)", //FIXME: What do these two mean? false, // isMain, false // isOptimized ); // if the linkage stays internal, we can't llvm-link the generated modules together: // llvm's DwarfWriter uses path and filename to determine the symbol name and we'd // end up with duplicate symbols m->ir.irModule->diCompileUnit.getGV()->setLinkage(DEBUGINFO_LINKONCE_LINKAGE_TYPE); m->ir.irModule->diCompileUnit.getGV()->setName(std::string("llvm.dbg.compile_unit_") + srcpath + m->srcfile->name->toChars()); return m->ir.irModule->diCompileUnit; } ////////////////////////////////////////////////////////////////////////////////////////////////// llvm::DISubprogram DtoDwarfSubProgram(FuncDeclaration* fd) { Logger::println("D to dwarf subprogram"); LOG_SCOPE; llvm::DICompileUnit context = DtoDwarfCompileUnit(gIR->dmodule); llvm::DICompileUnit definition = DtoDwarfCompileUnit(getDefinedModule(fd)); // FIXME: duplicates ? return gIR->difactory.CreateSubprogram( context, // context fd->toPrettyChars(), // name fd->toPrettyChars(), // display name fd->mangle(), // linkage name definition, // compile unit fd->loc.linnum, // line no //FIXME: what's this type for? llvm::DIType(NULL), // type fd->protection == PROTprivate, // is local to unit context.getGV() == definition.getGV() // isdefinition ); } ////////////////////////////////////////////////////////////////////////////////////////////////// llvm::DISubprogram DtoDwarfSubProgramInternal(const char* prettyname, const char* mangledname) { Logger::println("D to dwarf subprogram"); LOG_SCOPE; llvm::DICompileUnit context = DtoDwarfCompileUnit(gIR->dmodule); // FIXME: duplicates ? return gIR->difactory.CreateSubprogram( context, // context prettyname, // name prettyname, // display name mangledname, // linkage name context, // compile unit 0, // line no //FIXME: what's this type for? llvm::DIType(NULL), // type true, // is local to unit true // isdefinition ); } ////////////////////////////////////////////////////////////////////////////////////////////////// llvm::DIGlobalVariable DtoDwarfGlobalVariable(LLGlobalVariable* ll, VarDeclaration* vd) { Logger::println("D to dwarf global_variable"); LOG_SCOPE; // FIXME: duplicates ? return dwarfGlobalVariable(ll, vd); } ////////////////////////////////////////////////////////////////////////////////////////////////// void DtoDwarfFuncStart(FuncDeclaration* fd) { Logger::println("D to dwarf funcstart"); LOG_SCOPE; assert(!fd->ir.irFunc->diSubprogram.isNull()); gIR->difactory.InsertSubprogramStart(fd->ir.irFunc->diSubprogram, gIR->scopebb()); } ////////////////////////////////////////////////////////////////////////////////////////////////// void DtoDwarfFuncEnd(FuncDeclaration* fd) { Logger::println("D to dwarf funcend"); LOG_SCOPE; assert(!fd->ir.irFunc->diSubprogram.isNull()); gIR->difactory.InsertRegionEnd(fd->ir.irFunc->diSubprogram, gIR->scopebb()); } ////////////////////////////////////////////////////////////////////////////////////////////////// void DtoDwarfStopPoint(unsigned ln) { Logger::println("D to dwarf stoppoint at line %u", ln); LOG_SCOPE; gIR->difactory.InsertStopPoint( DtoDwarfCompileUnit(getDefinedModule(gIR->func()->decl)), // compile unit ln, // line no 0, // col no gIR->scopebb() ); }