| //===-- IRForTarget.cpp -------------------------------------------*- C++ -*-===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "lldb/Expression/IRForTarget.h" |
| |
| #include "llvm/Support/raw_ostream.h" |
| #include "llvm/InstrTypes.h" |
| #include "llvm/Instructions.h" |
| #include "llvm/Intrinsics.h" |
| #include "llvm/Module.h" |
| #include "llvm/Target/TargetData.h" |
| #include "llvm/ValueSymbolTable.h" |
| |
| #include "clang/AST/ASTContext.h" |
| |
| #include "lldb/Core/ConstString.h" |
| #include "lldb/Core/dwarf.h" |
| #include "lldb/Core/Log.h" |
| #include "lldb/Core/Scalar.h" |
| #include "lldb/Core/StreamString.h" |
| #include "lldb/Expression/ClangExpressionDeclMap.h" |
| |
| #include <map> |
| |
| using namespace llvm; |
| |
| static char ID; |
| |
| IRForTarget::IRForTarget (lldb_private::ClangExpressionDeclMap *decl_map, |
| bool resolve_vars, |
| lldb::ClangExpressionVariableSP *const_result, |
| lldb_private::Stream *error_stream, |
| const char *func_name) : |
| ModulePass(ID), |
| m_decl_map(decl_map), |
| m_CFStringCreateWithBytes(NULL), |
| m_sel_registerName(NULL), |
| m_func_name(func_name), |
| m_resolve_vars(resolve_vars), |
| m_const_result(const_result), |
| m_has_side_effects(false), |
| m_result_is_pointer(false), |
| m_error_stream(error_stream) |
| { |
| } |
| |
| /* Handy utility functions used at several places in the code */ |
| |
| static std::string |
| PrintValue(const Value *value, bool truncate = false) |
| { |
| std::string s; |
| raw_string_ostream rso(s); |
| value->print(rso); |
| rso.flush(); |
| if (truncate) |
| s.resize(s.length() - 1); |
| return s; |
| } |
| |
| static std::string |
| PrintType(const Type *type, bool truncate = false) |
| { |
| std::string s; |
| raw_string_ostream rso(s); |
| type->print(rso); |
| rso.flush(); |
| if (truncate) |
| s.resize(s.length() - 1); |
| return s; |
| } |
| |
| IRForTarget::~IRForTarget() |
| { |
| } |
| |
| bool |
| IRForTarget::HasSideEffects (llvm::Module &llvm_module, |
| llvm::Function &llvm_function) |
| { |
| llvm::Function::iterator bbi; |
| BasicBlock::iterator ii; |
| |
| for (bbi = llvm_function.begin(); |
| bbi != llvm_function.end(); |
| ++bbi) |
| { |
| BasicBlock &basic_block = *bbi; |
| |
| for (ii = basic_block.begin(); |
| ii != basic_block.end(); |
| ++ii) |
| { |
| switch (ii->getOpcode()) |
| { |
| default: |
| return true; |
| case Instruction::Store: |
| { |
| StoreInst *store_inst = dyn_cast<StoreInst>(ii); |
| |
| Value *store_ptr = store_inst->getPointerOperand(); |
| |
| if (!isa <AllocaInst> (store_ptr)) |
| return true; |
| else |
| break; |
| } |
| case Instruction::Load: |
| case Instruction::Alloca: |
| case Instruction::GetElementPtr: |
| case Instruction::Ret: |
| break; |
| } |
| } |
| } |
| |
| return false; |
| } |
| |
| void |
| IRForTarget::MaybeSetConstantResult (llvm::Constant *initializer, |
| const lldb_private::ConstString &name, |
| lldb_private::TypeFromParser type) |
| { |
| if (!m_const_result) |
| return; |
| |
| if (llvm::ConstantInt *init_int = dyn_cast<llvm::ConstantInt>(initializer)) |
| { |
| *m_const_result = m_decl_map->BuildIntegerVariable(name, type, init_int->getValue()); |
| } |
| } |
| |
| bool |
| IRForTarget::CreateResultVariable (llvm::Module &llvm_module, llvm::Function &llvm_function) |
| { |
| lldb::LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS)); |
| |
| if (!m_resolve_vars) |
| return true; |
| |
| // Find the result variable. If it doesn't exist, we can give up right here. |
| |
| ValueSymbolTable& value_symbol_table = llvm_module.getValueSymbolTable(); |
| |
| const char *result_name = NULL; |
| |
| for (ValueSymbolTable::iterator vi = value_symbol_table.begin(), ve = value_symbol_table.end(); |
| vi != ve; |
| ++vi) |
| { |
| if (strstr(vi->first(), "$__lldb_expr_result_ptr") && |
| !strstr(vi->first(), "GV")) |
| { |
| result_name = vi->first(); |
| m_result_is_pointer = true; |
| break; |
| } |
| |
| if (strstr(vi->first(), "$__lldb_expr_result") && |
| !strstr(vi->first(), "GV")) |
| { |
| result_name = vi->first(); |
| m_result_is_pointer = false; |
| break; |
| } |
| } |
| |
| if (!result_name) |
| { |
| if (log) |
| log->PutCString("Couldn't find result variable"); |
| |
| return true; |
| } |
| |
| if (log) |
| log->Printf("Result name: \"%s\"", result_name); |
| |
| Value *result_value = llvm_module.getNamedValue(result_name); |
| |
| if (!result_value) |
| { |
| if (log) |
| log->PutCString("Result variable had no data"); |
| |
| if (m_error_stream) |
| m_error_stream->Printf("Internal error [IRForTarget]: Result variable's name (%s) exists, but not its definition\n", result_name); |
| |
| return false; |
| } |
| |
| if (log) |
| log->Printf("Found result in the IR: \"%s\"", PrintValue(result_value, false).c_str()); |
| |
| GlobalVariable *result_global = dyn_cast<GlobalVariable>(result_value); |
| |
| if (!result_global) |
| { |
| if (log) |
| log->PutCString("Result variable isn't a GlobalVariable"); |
| |
| if (m_error_stream) |
| m_error_stream->Printf("Internal error [IRForTarget]: Result variable (%s) is defined, but is not a global variable\n", result_name); |
| |
| return false; |
| } |
| |
| // Find the metadata and follow it to the VarDecl |
| |
| NamedMDNode *named_metadata = llvm_module.getNamedMetadata("clang.global.decl.ptrs"); |
| |
| if (!named_metadata) |
| { |
| if (log) |
| log->PutCString("No global metadata"); |
| |
| if (m_error_stream) |
| m_error_stream->Printf("Internal error [IRForTarget]: No metadata\n"); |
| |
| return false; |
| } |
| |
| unsigned num_nodes = named_metadata->getNumOperands(); |
| unsigned node_index; |
| |
| MDNode *metadata_node = NULL; |
| |
| for (node_index = 0; |
| node_index < num_nodes; |
| ++node_index) |
| { |
| metadata_node = named_metadata->getOperand(node_index); |
| |
| if (metadata_node->getNumOperands() != 2) |
| continue; |
| |
| if (metadata_node->getOperand(0) == result_global) |
| break; |
| } |
| |
| if (!metadata_node) |
| { |
| if (log) |
| log->PutCString("Couldn't find result metadata"); |
| |
| if (m_error_stream) |
| m_error_stream->Printf("Internal error [IRForTarget]: Result variable (%s) is a global variable, but has no metadata\n", result_name); |
| |
| return false; |
| } |
| |
| ConstantInt *constant_int = dyn_cast<ConstantInt>(metadata_node->getOperand(1)); |
| |
| lldb::addr_t result_decl_intptr = constant_int->getZExtValue(); |
| |
| clang::VarDecl *result_decl = reinterpret_cast<clang::VarDecl *>(result_decl_intptr); |
| |
| // Get the next available result name from m_decl_map and create the persistent |
| // variable for it |
| |
| lldb_private::TypeFromParser result_decl_type; |
| |
| if (m_result_is_pointer) |
| { |
| clang::QualType pointer_qual_type = result_decl->getType(); |
| const clang::Type *pointer_type = pointer_qual_type.getTypePtr(); |
| const clang::PointerType *pointer_pointertype = dyn_cast<clang::PointerType>(pointer_type); |
| |
| if (!pointer_pointertype) |
| { |
| if (log) |
| log->PutCString("Expected result to have pointer type, but it did not"); |
| |
| if (m_error_stream) |
| m_error_stream->Printf("Internal error [IRForTarget]: Lvalue result (%s) is not a pointer variable\n", result_name); |
| |
| return false; |
| } |
| |
| clang::QualType element_qual_type = pointer_pointertype->getPointeeType(); |
| |
| result_decl_type = lldb_private::TypeFromParser(element_qual_type.getAsOpaquePtr(), |
| &result_decl->getASTContext()); |
| } |
| else |
| { |
| result_decl_type = lldb_private::TypeFromParser(result_decl->getType().getAsOpaquePtr(), |
| &result_decl->getASTContext()); |
| } |
| |
| m_result_name = m_decl_map->GetPersistentResultName(); |
| // If the result is an Lvalue, it is emitted as a pointer; see |
| // ASTResultSynthesizer::SynthesizeBodyResult. |
| m_decl_map->AddPersistentVariable(result_decl, |
| m_result_name, |
| result_decl_type, |
| true, |
| m_result_is_pointer); |
| |
| if (log) |
| log->Printf("Creating a new result global: \"%s\"", m_result_name.GetCString()); |
| |
| // Construct a new result global and set up its metadata |
| |
| GlobalVariable *new_result_global = new GlobalVariable(llvm_module, |
| result_global->getType()->getElementType(), |
| false, /* not constant */ |
| GlobalValue::ExternalLinkage, |
| NULL, /* no initializer */ |
| m_result_name.GetCString ()); |
| |
| // It's too late in compilation to create a new VarDecl for this, but we don't |
| // need to. We point the metadata at the old VarDecl. This creates an odd |
| // anomaly: a variable with a Value whose name is something like $0 and a |
| // Decl whose name is $__lldb_expr_result. This condition is handled in |
| // ClangExpressionDeclMap::DoMaterialize, and the name of the variable is |
| // fixed up. |
| |
| ConstantInt *new_constant_int = ConstantInt::get(constant_int->getType(), |
| result_decl_intptr, |
| false); |
| |
| llvm::Value* values[2]; |
| values[0] = new_result_global; |
| values[1] = new_constant_int; |
| |
| MDNode *persistent_global_md = MDNode::get(llvm_module.getContext(), values, 2); |
| named_metadata->addOperand(persistent_global_md); |
| |
| if (log) |
| log->Printf("Replacing \"%s\" with \"%s\"", |
| PrintValue(result_global).c_str(), |
| PrintValue(new_result_global).c_str()); |
| |
| if (result_global->hasNUses(0)) |
| { |
| // We need to synthesize a store for this variable, because otherwise |
| // there's nothing to put into its equivalent persistent variable. |
| |
| BasicBlock &entry_block(llvm_function.getEntryBlock()); |
| Instruction *first_entry_instruction(entry_block.getFirstNonPHIOrDbg()); |
| |
| if (!first_entry_instruction) |
| return false; |
| |
| if (!result_global->hasInitializer()) |
| { |
| if (log) |
| log->Printf("Couldn't find initializer for unused variable"); |
| |
| if (m_error_stream) |
| m_error_stream->Printf("Internal error [IRForTarget]: Result variable (%s) has no writes and no initializer\n", result_name); |
| |
| return false; |
| } |
| |
| Constant *initializer = result_global->getInitializer(); |
| |
| // Here we write the initializer into a result variable assuming it |
| // can be computed statically. |
| |
| if (!m_has_side_effects) |
| { |
| MaybeSetConstantResult (initializer, |
| m_result_name, |
| result_decl_type); |
| } |
| |
| StoreInst *synthesized_store = new StoreInst(initializer, |
| new_result_global, |
| first_entry_instruction); |
| |
| if (log) |
| log->Printf("Synthesized result store \"%s\"\n", PrintValue(synthesized_store).c_str()); |
| } |
| else |
| { |
| result_global->replaceAllUsesWith(new_result_global); |
| } |
| |
| result_global->eraseFromParent(); |
| |
| return true; |
| } |
| |
| static void DebugUsers(lldb::LogSP &log, Value *value, uint8_t depth) |
| { |
| if (!depth) |
| return; |
| |
| depth--; |
| |
| log->Printf(" <Begin %d users>", value->getNumUses()); |
| |
| for (Value::use_iterator ui = value->use_begin(), ue = value->use_end(); |
| ui != ue; |
| ++ui) |
| { |
| log->Printf(" <Use %p> %s", *ui, PrintValue(*ui).c_str()); |
| DebugUsers(log, *ui, depth); |
| } |
| |
| log->Printf(" <End uses>"); |
| } |
| |
| bool |
| IRForTarget::RewriteObjCConstString (llvm::Module &llvm_module, |
| llvm::GlobalVariable *ns_str, |
| llvm::GlobalVariable *cstr, |
| Instruction *FirstEntryInstruction) |
| { |
| lldb::LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS)); |
| |
| const Type *i8_ptr_ty = Type::getInt8PtrTy(llvm_module.getContext()); |
| const IntegerType *intptr_ty = Type::getIntNTy(llvm_module.getContext(), |
| (llvm_module.getPointerSize() == Module::Pointer64) ? 64 : 32); |
| const Type *i32_ty = Type::getInt32Ty(llvm_module.getContext()); |
| const Type *i8_ty = Type::getInt8Ty(llvm_module.getContext()); |
| |
| if (!m_CFStringCreateWithBytes) |
| { |
| lldb::addr_t CFStringCreateWithBytes_addr; |
| |
| static lldb_private::ConstString g_CFStringCreateWithBytes_str ("CFStringCreateWithBytes"); |
| |
| if (!m_decl_map->GetFunctionAddress (g_CFStringCreateWithBytes_str, CFStringCreateWithBytes_addr)) |
| { |
| if (log) |
| log->PutCString("Couldn't find CFStringCreateWithBytes in the target"); |
| |
| if (m_error_stream) |
| m_error_stream->Printf("Error [IRForTarget]: Rewriting an Objective-C constant string requires CFStringCreateWithBytes\n"); |
| |
| return false; |
| } |
| |
| if (log) |
| log->Printf("Found CFStringCreateWithBytes at 0x%llx", CFStringCreateWithBytes_addr); |
| |
| // Build the function type: |
| // |
| // CFStringRef CFStringCreateWithBytes ( |
| // CFAllocatorRef alloc, |
| // const UInt8 *bytes, |
| // CFIndex numBytes, |
| // CFStringEncoding encoding, |
| // Boolean isExternalRepresentation |
| // ); |
| // |
| // We make the following substitutions: |
| // |
| // CFStringRef -> i8* |
| // CFAllocatorRef -> i8* |
| // UInt8 * -> i8* |
| // CFIndex -> long (i32 or i64, as appropriate; we ask the module for its pointer size for now) |
| // CFStringEncoding -> i32 |
| // Boolean -> i8 |
| |
| std::vector <const Type *> CFSCWB_arg_types; |
| CFSCWB_arg_types.push_back(i8_ptr_ty); |
| CFSCWB_arg_types.push_back(i8_ptr_ty); |
| CFSCWB_arg_types.push_back(intptr_ty); |
| CFSCWB_arg_types.push_back(i32_ty); |
| CFSCWB_arg_types.push_back(i8_ty); |
| llvm::Type *CFSCWB_ty = FunctionType::get(i8_ptr_ty, CFSCWB_arg_types, false); |
| |
| // Build the constant containing the pointer to the function |
| PointerType *CFSCWB_ptr_ty = PointerType::getUnqual(CFSCWB_ty); |
| Constant *CFSCWB_addr_int = ConstantInt::get(intptr_ty, CFStringCreateWithBytes_addr, false); |
| m_CFStringCreateWithBytes = ConstantExpr::getIntToPtr(CFSCWB_addr_int, CFSCWB_ptr_ty); |
| } |
| |
| ConstantArray *string_array; |
| |
| if (cstr) |
| string_array = dyn_cast<ConstantArray>(cstr->getInitializer()); |
| else |
| string_array = NULL; |
| |
| SmallVector <Value*, 5> CFSCWB_arguments; |
| |
| Constant *alloc_arg = Constant::getNullValue(i8_ptr_ty); |
| Constant *bytes_arg = cstr ? ConstantExpr::getBitCast(cstr, i8_ptr_ty) : Constant::getNullValue(i8_ptr_ty); |
| Constant *numBytes_arg = ConstantInt::get(intptr_ty, cstr ? string_array->getType()->getNumElements() - 1 : 0, false); |
| Constant *encoding_arg = ConstantInt::get(i32_ty, 0x0600, false); /* 0x0600 is kCFStringEncodingASCII */ |
| Constant *isExternal_arg = ConstantInt::get(i8_ty, 0x0, false); /* 0x0 is false */ |
| |
| CFSCWB_arguments.push_back(alloc_arg); |
| CFSCWB_arguments.push_back(bytes_arg); |
| CFSCWB_arguments.push_back(numBytes_arg); |
| CFSCWB_arguments.push_back(encoding_arg); |
| CFSCWB_arguments.push_back(isExternal_arg); |
| |
| CallInst *CFSCWB_call = CallInst::Create(m_CFStringCreateWithBytes, |
| CFSCWB_arguments.begin(), |
| CFSCWB_arguments.end(), |
| "CFStringCreateWithBytes", |
| FirstEntryInstruction); |
| |
| if (!UnfoldConstant(ns_str, CFSCWB_call, FirstEntryInstruction)) |
| { |
| if (log) |
| log->PutCString("Couldn't replace the NSString with the result of the call"); |
| |
| if (m_error_stream) |
| m_error_stream->Printf("Error [IRForTarget]: Couldn't replace an Objective-C constant string with a dynamic string\n"); |
| |
| return false; |
| } |
| |
| ns_str->eraseFromParent(); |
| |
| return true; |
| } |
| |
| bool |
| IRForTarget::RewriteObjCConstStrings(Module &llvm_module, Function &llvm_function) |
| { |
| lldb::LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS)); |
| |
| ValueSymbolTable& value_symbol_table = llvm_module.getValueSymbolTable(); |
| |
| BasicBlock &entry_block(llvm_function.getEntryBlock()); |
| Instruction *FirstEntryInstruction(entry_block.getFirstNonPHIOrDbg()); |
| |
| if (!FirstEntryInstruction) |
| { |
| if (log) |
| log->PutCString("Couldn't find first instruction for rewritten Objective-C strings"); |
| |
| if (m_error_stream) |
| m_error_stream->Printf("Internal error [IRForTarget]: Couldn't find the location for calls to CFStringCreateWithBytes\n"); |
| |
| return false; |
| } |
| |
| for (ValueSymbolTable::iterator vi = value_symbol_table.begin(), ve = value_symbol_table.end(); |
| vi != ve; |
| ++vi) |
| { |
| if (strstr(vi->first(), "_unnamed_cfstring_")) |
| { |
| Value *nsstring_value = vi->second; |
| |
| GlobalVariable *nsstring_global = dyn_cast<GlobalVariable>(nsstring_value); |
| |
| if (!nsstring_global) |
| { |
| if (log) |
| log->PutCString("NSString variable is not a GlobalVariable"); |
| |
| if (m_error_stream) |
| m_error_stream->Printf("Internal error [IRForTarget]: An Objective-C constant string is not a global variable\n"); |
| |
| return false; |
| } |
| |
| if (!nsstring_global->hasInitializer()) |
| { |
| if (log) |
| log->PutCString("NSString variable does not have an initializer"); |
| |
| if (m_error_stream) |
| m_error_stream->Printf("Internal error [IRForTarget]: An Objective-C constant string does not have an initializer\n"); |
| |
| return false; |
| } |
| |
| ConstantStruct *nsstring_struct = dyn_cast<ConstantStruct>(nsstring_global->getInitializer()); |
| |
| if (!nsstring_struct) |
| { |
| if (log) |
| log->PutCString("NSString variable's initializer is not a ConstantStruct"); |
| |
| if (m_error_stream) |
| m_error_stream->Printf("Internal error [IRForTarget]: An Objective-C constant string is not a structure constant\n"); |
| |
| return false; |
| } |
| |
| // We expect the following structure: |
| // |
| // struct { |
| // int *isa; |
| // int flags; |
| // char *str; |
| // long length; |
| // }; |
| |
| if (nsstring_struct->getNumOperands() != 4) |
| { |
| if (log) |
| log->Printf("NSString variable's initializer structure has an unexpected number of members. Should be 4, is %d", nsstring_struct->getNumOperands()); |
| |
| if (m_error_stream) |
| m_error_stream->Printf("Internal error [IRForTarget]: The struct for an Objective-C constant string is not as expected\n"); |
| |
| return false; |
| } |
| |
| Constant *nsstring_member = nsstring_struct->getOperand(2); |
| |
| if (!nsstring_member) |
| { |
| if (log) |
| log->PutCString("NSString initializer's str element was empty"); |
| |
| if (m_error_stream) |
| m_error_stream->Printf("Internal error [IRForTarget]: An Objective-C constant string does not have a string initializer\n"); |
| |
| return false; |
| } |
| |
| ConstantExpr *nsstring_expr = dyn_cast<ConstantExpr>(nsstring_member); |
| |
| if (!nsstring_expr) |
| { |
| if (log) |
| log->PutCString("NSString initializer's str element is not a ConstantExpr"); |
| |
| if (m_error_stream) |
| m_error_stream->Printf("Internal error [IRForTarget]: An Objective-C constant string's string initializer is not constant\n"); |
| |
| return false; |
| } |
| |
| if (nsstring_expr->getOpcode() != Instruction::GetElementPtr) |
| { |
| if (log) |
| log->Printf("NSString initializer's str element is not a GetElementPtr expression, it's a %s", nsstring_expr->getOpcodeName()); |
| |
| if (m_error_stream) |
| m_error_stream->Printf("Internal error [IRForTarget]: An Objective-C constant string's string initializer is not an array\n"); |
| |
| return false; |
| } |
| |
| Constant *nsstring_cstr = nsstring_expr->getOperand(0); |
| |
| GlobalVariable *cstr_global = dyn_cast<GlobalVariable>(nsstring_cstr); |
| |
| if (!cstr_global) |
| { |
| if (log) |
| log->PutCString("NSString initializer's str element is not a GlobalVariable"); |
| |
| if (m_error_stream) |
| m_error_stream->Printf("Internal error [IRForTarget]: An Objective-C constant string's string initializer doesn't point to a global\n"); |
| |
| return false; |
| } |
| |
| if (!cstr_global->hasInitializer()) |
| { |
| if (log) |
| log->PutCString("NSString initializer's str element does not have an initializer"); |
| |
| if (m_error_stream) |
| m_error_stream->Printf("Internal error [IRForTarget]: An Objective-C constant string's string initializer doesn't point to initialized data\n"); |
| |
| return false; |
| } |
| |
| /* |
| if (!cstr_array) |
| { |
| if (log) |
| log->PutCString("NSString initializer's str element is not a ConstantArray"); |
| |
| if (m_error_stream) |
| m_error_stream->Printf("Internal error [IRForTarget]: An Objective-C constant string's string initializer doesn't point to an array\n"); |
| |
| return false; |
| } |
| |
| if (!cstr_array->isCString()) |
| { |
| if (log) |
| log->PutCString("NSString initializer's str element is not a C string array"); |
| |
| if (m_error_stream) |
| m_error_stream->Printf("Internal error [IRForTarget]: An Objective-C constant string's string initializer doesn't point to a C string\n"); |
| |
| return false; |
| } |
| */ |
| |
| ConstantArray *cstr_array = dyn_cast<ConstantArray>(cstr_global->getInitializer()); |
| |
| if (log) |
| { |
| if (cstr_array) |
| log->Printf("Found NSString constant %s, which contains \"%s\"", vi->first(), cstr_array->getAsString().c_str()); |
| else |
| log->Printf("Found NSString constant %s, which contains \"\"", vi->first()); |
| } |
| |
| if (!cstr_array) |
| cstr_global = NULL; |
| |
| if (!RewriteObjCConstString(llvm_module, nsstring_global, cstr_global, FirstEntryInstruction)) |
| { |
| if (log) |
| log->PutCString("Error rewriting the constant string"); |
| |
| // We don't print an error message here because RewriteObjCConstString has done so for us. |
| |
| return false; |
| } |
| } |
| } |
| |
| for (ValueSymbolTable::iterator vi = value_symbol_table.begin(), ve = value_symbol_table.end(); |
| vi != ve; |
| ++vi) |
| { |
| if (!strcmp(vi->first(), "__CFConstantStringClassReference")) |
| { |
| GlobalVariable *gv = dyn_cast<GlobalVariable>(vi->second); |
| |
| if (!gv) |
| { |
| if (log) |
| log->PutCString("__CFConstantStringClassReference is not a global variable"); |
| |
| if (m_error_stream) |
| m_error_stream->Printf("Internal error [IRForTarget]: Found a CFConstantStringClassReference, but it is not a global object\n"); |
| |
| return false; |
| } |
| |
| gv->eraseFromParent(); |
| |
| break; |
| } |
| } |
| |
| return true; |
| } |
| |
| static bool IsObjCSelectorRef (Value *value) |
| { |
| GlobalVariable *global_variable = dyn_cast<GlobalVariable>(value); |
| |
| if (!global_variable || !global_variable->hasName() || !global_variable->getName().startswith("\01L_OBJC_SELECTOR_REFERENCES_")) |
| return false; |
| |
| return true; |
| } |
| |
| // This function does not report errors; its callers are responsible. |
| bool |
| IRForTarget::RewriteObjCSelector (Instruction* selector_load, Module &llvm_module) |
| { |
| lldb::LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS)); |
| |
| LoadInst *load = dyn_cast<LoadInst>(selector_load); |
| |
| if (!load) |
| return false; |
| |
| // Unpack the message name from the selector. In LLVM IR, an objc_msgSend gets represented as |
| // |
| // %tmp = load i8** @"\01L_OBJC_SELECTOR_REFERENCES_" ; <i8*> |
| // %call = call i8* (i8*, i8*, ...)* @objc_msgSend(i8* %obj, i8* %tmp, ...) ; <i8*> |
| // |
| // where %obj is the object pointer and %tmp is the selector. |
| // |
| // @"\01L_OBJC_SELECTOR_REFERENCES_" is a pointer to a character array called @"\01L_OBJC_llvm_moduleETH_VAR_NAllvm_moduleE_". |
| // @"\01L_OBJC_llvm_moduleETH_VAR_NAllvm_moduleE_" contains the string. |
| |
| // Find the pointer's initializer (a ConstantExpr with opcode GetElementPtr) and get the string from its target |
| |
| GlobalVariable *_objc_selector_references_ = dyn_cast<GlobalVariable>(load->getPointerOperand()); |
| |
| if (!_objc_selector_references_ || !_objc_selector_references_->hasInitializer()) |
| return false; |
| |
| Constant *osr_initializer = _objc_selector_references_->getInitializer(); |
| |
| ConstantExpr *osr_initializer_expr = dyn_cast<ConstantExpr>(osr_initializer); |
| |
| if (!osr_initializer_expr || osr_initializer_expr->getOpcode() != Instruction::GetElementPtr) |
| return false; |
| |
| Value *osr_initializer_base = osr_initializer_expr->getOperand(0); |
| |
| if (!osr_initializer_base) |
| return false; |
| |
| // Find the string's initializer (a ConstantArray) and get the string from it |
| |
| GlobalVariable *_objc_meth_var_name_ = dyn_cast<GlobalVariable>(osr_initializer_base); |
| |
| if (!_objc_meth_var_name_ || !_objc_meth_var_name_->hasInitializer()) |
| return false; |
| |
| Constant *omvn_initializer = _objc_meth_var_name_->getInitializer(); |
| |
| ConstantArray *omvn_initializer_array = dyn_cast<ConstantArray>(omvn_initializer); |
| |
| if (!omvn_initializer_array->isString()) |
| return false; |
| |
| std::string omvn_initializer_string = omvn_initializer_array->getAsString(); |
| |
| if (log) |
| log->Printf("Found Objective-C selector reference \"%s\"", omvn_initializer_string.c_str()); |
| |
| // Construct a call to sel_registerName |
| |
| if (!m_sel_registerName) |
| { |
| lldb::addr_t sel_registerName_addr; |
| |
| static lldb_private::ConstString g_sel_registerName_str ("sel_registerName"); |
| if (!m_decl_map->GetFunctionAddress (g_sel_registerName_str, sel_registerName_addr)) |
| return false; |
| |
| if (log) |
| log->Printf("Found sel_registerName at 0x%llx", sel_registerName_addr); |
| |
| // Build the function type: struct objc_selector *sel_registerName(uint8_t*) |
| |
| // The below code would be "more correct," but in actuality what's required is uint8_t* |
| //Type *sel_type = StructType::get(llvm_module.getContext()); |
| //Type *sel_ptr_type = PointerType::getUnqual(sel_type); |
| const Type *sel_ptr_type = Type::getInt8PtrTy(llvm_module.getContext()); |
| |
| std::vector <const Type *> srN_arg_types; |
| srN_arg_types.push_back(Type::getInt8PtrTy(llvm_module.getContext())); |
| llvm::Type *srN_type = FunctionType::get(sel_ptr_type, srN_arg_types, false); |
| |
| // Build the constant containing the pointer to the function |
| const IntegerType *intptr_ty = Type::getIntNTy(llvm_module.getContext(), |
| (llvm_module.getPointerSize() == Module::Pointer64) ? 64 : 32); |
| PointerType *srN_ptr_ty = PointerType::getUnqual(srN_type); |
| Constant *srN_addr_int = ConstantInt::get(intptr_ty, sel_registerName_addr, false); |
| m_sel_registerName = ConstantExpr::getIntToPtr(srN_addr_int, srN_ptr_ty); |
| } |
| |
| SmallVector <Value*, 1> srN_arguments; |
| |
| Constant *omvn_pointer = ConstantExpr::getBitCast(_objc_meth_var_name_, Type::getInt8PtrTy(llvm_module.getContext())); |
| |
| srN_arguments.push_back(omvn_pointer); |
| |
| CallInst *srN_call = CallInst::Create(m_sel_registerName, |
| srN_arguments.begin(), |
| srN_arguments.end(), |
| "sel_registerName", |
| selector_load); |
| |
| // Replace the load with the call in all users |
| |
| selector_load->replaceAllUsesWith(srN_call); |
| |
| selector_load->eraseFromParent(); |
| |
| return true; |
| } |
| |
| bool |
| IRForTarget::RewriteObjCSelectors (Module &llvm_module, BasicBlock &basic_block) |
| { |
| lldb::LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS)); |
| |
| BasicBlock::iterator ii; |
| |
| typedef SmallVector <Instruction*, 2> InstrList; |
| typedef InstrList::iterator InstrIterator; |
| |
| InstrList selector_loads; |
| |
| for (ii = basic_block.begin(); |
| ii != basic_block.end(); |
| ++ii) |
| { |
| Instruction &inst = *ii; |
| |
| if (LoadInst *load = dyn_cast<LoadInst>(&inst)) |
| if (IsObjCSelectorRef(load->getPointerOperand())) |
| selector_loads.push_back(&inst); |
| } |
| |
| InstrIterator iter; |
| |
| for (iter = selector_loads.begin(); |
| iter != selector_loads.end(); |
| ++iter) |
| { |
| if (!RewriteObjCSelector(*iter, llvm_module)) |
| { |
| if (m_error_stream) |
| m_error_stream->Printf("Internal error [IRForTarget]: Couldn't change a static reference to an Objective-C selector to a dynamic reference\n"); |
| |
| if(log) |
| log->PutCString("Couldn't rewrite a reference to an Objective-C selector"); |
| |
| return false; |
| } |
| } |
| |
| return true; |
| } |
| |
| // This function does not report errors; its callers are responsible. |
| bool |
| IRForTarget::RewritePersistentAlloc (llvm::Instruction *persistent_alloc, |
| llvm::Module &llvm_module) |
| { |
| lldb::LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS)); |
| |
| AllocaInst *alloc = dyn_cast<AllocaInst>(persistent_alloc); |
| |
| MDNode *alloc_md = alloc->getMetadata("clang.decl.ptr"); |
| |
| if (!alloc_md || !alloc_md->getNumOperands()) |
| return false; |
| |
| ConstantInt *constant_int = dyn_cast<ConstantInt>(alloc_md->getOperand(0)); |
| |
| if (!constant_int) |
| return false; |
| |
| // We attempt to register this as a new persistent variable with the DeclMap. |
| |
| uintptr_t ptr = constant_int->getZExtValue(); |
| |
| clang::VarDecl *decl = reinterpret_cast<clang::VarDecl *>(ptr); |
| |
| lldb_private::TypeFromParser result_decl_type (decl->getType().getAsOpaquePtr(), |
| &decl->getASTContext()); |
| |
| StringRef decl_name (decl->getName()); |
| lldb_private::ConstString persistent_variable_name (decl_name.data(), decl_name.size()); |
| if (!m_decl_map->AddPersistentVariable(decl, persistent_variable_name, result_decl_type, false, false)) |
| return false; |
| |
| GlobalVariable *persistent_global = new GlobalVariable(llvm_module, |
| alloc->getType(), |
| false, /* not constant */ |
| GlobalValue::ExternalLinkage, |
| NULL, /* no initializer */ |
| alloc->getName().str().c_str()); |
| |
| // What we're going to do here is make believe this was a regular old external |
| // variable. That means we need to make the metadata valid. |
| |
| NamedMDNode *named_metadata = llvm_module.getNamedMetadata("clang.global.decl.ptrs"); |
| |
| llvm::Value* values[2]; |
| values[0] = persistent_global; |
| values[1] = constant_int; |
| |
| MDNode *persistent_global_md = MDNode::get(llvm_module.getContext(), values, 2); |
| named_metadata->addOperand(persistent_global_md); |
| |
| // Now, since the variable is a pointer variable, we will drop in a load of that |
| // pointer variable. |
| |
| LoadInst *persistent_load = new LoadInst (persistent_global, "", alloc); |
| |
| if (log) |
| log->Printf("Replacing \"%s\" with \"%s\"", |
| PrintValue(alloc).c_str(), |
| PrintValue(persistent_load).c_str()); |
| |
| alloc->replaceAllUsesWith(persistent_load); |
| alloc->eraseFromParent(); |
| |
| return true; |
| } |
| |
| bool |
| IRForTarget::RewritePersistentAllocs(llvm::Module &llvm_module, llvm::BasicBlock &basic_block) |
| { |
| if (!m_resolve_vars) |
| return true; |
| |
| lldb::LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS)); |
| |
| BasicBlock::iterator ii; |
| |
| typedef SmallVector <Instruction*, 2> InstrList; |
| typedef InstrList::iterator InstrIterator; |
| |
| InstrList pvar_allocs; |
| |
| for (ii = basic_block.begin(); |
| ii != basic_block.end(); |
| ++ii) |
| { |
| Instruction &inst = *ii; |
| |
| if (AllocaInst *alloc = dyn_cast<AllocaInst>(&inst)) |
| { |
| llvm::StringRef alloc_name = alloc->getName(); |
| |
| if (alloc_name.startswith("$") && |
| !alloc_name.startswith("$__lldb")) |
| { |
| if (alloc_name.find_first_of("0123456789") == 1) |
| { |
| if (log) |
| log->Printf("Rejecting a numeric persistent variable."); |
| |
| if (m_error_stream) |
| m_error_stream->Printf("Error [IRForTarget]: Names starting with $0, $1, ... are reserved for use as result names\n"); |
| |
| return false; |
| } |
| |
| pvar_allocs.push_back(alloc); |
| } |
| } |
| } |
| |
| InstrIterator iter; |
| |
| for (iter = pvar_allocs.begin(); |
| iter != pvar_allocs.end(); |
| ++iter) |
| { |
| if (!RewritePersistentAlloc(*iter, llvm_module)) |
| { |
| if (m_error_stream) |
| m_error_stream->Printf("Internal error [IRForTarget]: Couldn't rewrite the creation of a persistent variable\n"); |
| |
| if(log) |
| log->PutCString("Couldn't rewrite the creation of a persistent variable"); |
| |
| return false; |
| } |
| } |
| |
| return true; |
| } |
| |
| static clang::NamedDecl * |
| DeclForGlobalValue(Module &module, GlobalValue *global_value) |
| { |
| NamedMDNode *named_metadata = module.getNamedMetadata("clang.global.decl.ptrs"); |
| |
| if (!named_metadata) |
| return NULL; |
| |
| unsigned num_nodes = named_metadata->getNumOperands(); |
| unsigned node_index; |
| |
| for (node_index = 0; |
| node_index < num_nodes; |
| ++node_index) |
| { |
| MDNode *metadata_node = named_metadata->getOperand(node_index); |
| |
| if (!metadata_node) |
| return NULL; |
| |
| if (metadata_node->getNumOperands() != 2) |
| continue; |
| |
| if (metadata_node->getOperand(0) != global_value) |
| continue; |
| |
| ConstantInt *constant_int = dyn_cast<ConstantInt>(metadata_node->getOperand(1)); |
| |
| if (!constant_int) |
| return NULL; |
| |
| uintptr_t ptr = constant_int->getZExtValue(); |
| |
| return reinterpret_cast<clang::NamedDecl *>(ptr); |
| } |
| |
| return NULL; |
| } |
| |
| // This function does not report errors; its callers are responsible. |
| bool |
| IRForTarget::MaybeHandleVariable (Module &llvm_module, Value *llvm_value_ptr) |
| { |
| lldb::LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS)); |
| |
| if (log) |
| log->Printf("MaybeHandleVariable (%s)", PrintValue(llvm_value_ptr).c_str()); |
| |
| if (ConstantExpr *constant_expr = dyn_cast<ConstantExpr>(llvm_value_ptr)) |
| { |
| switch (constant_expr->getOpcode()) |
| { |
| default: |
| break; |
| case Instruction::GetElementPtr: |
| case Instruction::BitCast: |
| Value *s = constant_expr->getOperand(0); |
| if (!MaybeHandleVariable(llvm_module, s)) |
| return false; |
| } |
| } |
| else if (GlobalVariable *global_variable = dyn_cast<GlobalVariable>(llvm_value_ptr)) |
| { |
| clang::NamedDecl *named_decl = DeclForGlobalValue(llvm_module, global_variable); |
| |
| if (!named_decl) |
| { |
| if (IsObjCSelectorRef(llvm_value_ptr)) |
| return true; |
| |
| if (!global_variable->hasExternalLinkage()) |
| return true; |
| |
| if (log) |
| log->Printf("Found global variable \"%s\" without metadata", global_variable->getName().str().c_str()); |
| |
| return false; |
| } |
| |
| std::string name (named_decl->getName().str()); |
| |
| void *opaque_type = NULL; |
| clang::ASTContext *ast_context = NULL; |
| |
| if (clang::ValueDecl *value_decl = dyn_cast<clang::ValueDecl>(named_decl)) |
| { |
| opaque_type = value_decl->getType().getAsOpaquePtr(); |
| ast_context = &value_decl->getASTContext(); |
| } |
| else |
| { |
| return false; |
| } |
| |
| clang::QualType qual_type; |
| const Type *value_type; |
| |
| if (name[0] == '$') |
| { |
| // The $__lldb_expr_result name indicates the the return value has allocated as |
| // a static variable. Per the comment at ASTResultSynthesizer::SynthesizeBodyResult, |
| // accesses to this static variable need to be redirected to the result of dereferencing |
| // a pointer that is passed in as one of the arguments. |
| // |
| // Consequently, when reporting the size of the type, we report a pointer type pointing |
| // to the type of $__lldb_expr_result, not the type itself. |
| // |
| // We also do this for any user-declared persistent variables. |
| |
| qual_type = ast_context->getPointerType(clang::QualType::getFromOpaquePtr(opaque_type)); |
| value_type = PointerType::get(global_variable->getType(), 0); |
| } |
| else |
| { |
| qual_type = clang::QualType::getFromOpaquePtr(opaque_type); |
| value_type = global_variable->getType(); |
| } |
| |
| size_t value_size = (ast_context->getTypeSize(qual_type) + 7) / 8; |
| off_t value_alignment = (ast_context->getTypeAlign(qual_type) + 7) / 8; |
| |
| if (log) |
| log->Printf("Type of \"%s\" is [clang \"%s\", llvm \"%s\"] [size %d, align %d]", |
| name.c_str(), |
| qual_type.getAsString().c_str(), |
| PrintType(value_type).c_str(), |
| value_size, |
| value_alignment); |
| |
| |
| if (named_decl && !m_decl_map->AddValueToStruct(named_decl, |
| lldb_private::ConstString (name.c_str()), |
| llvm_value_ptr, |
| value_size, |
| value_alignment)) |
| return false; |
| } |
| else if (dyn_cast<llvm::Function>(llvm_value_ptr)) |
| { |
| if (log) |
| log->Printf("Function pointers aren't handled right now"); |
| |
| return false; |
| } |
| |
| return true; |
| } |
| |
| // This function does not report errors; its callers are responsible. |
| bool |
| IRForTarget::HandleSymbol (Module &llvm_module, |
| Value *symbol) |
| { |
| lldb::LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS)); |
| |
| lldb_private::ConstString name(symbol->getName().str().c_str()); |
| |
| uint64_t symbol_addr; |
| |
| if (!m_decl_map->GetSymbolAddress (name, symbol_addr)) |
| { |
| if (log) |
| log->Printf ("Symbol \"%s\" had no address", name.GetCString()); |
| |
| return false; |
| } |
| |
| if (log) |
| log->Printf("Found \"%s\" at 0x%llx", name.GetCString(), symbol_addr); |
| |
| const Type *symbol_type = symbol->getType(); |
| |
| const IntegerType *intptr_ty = Type::getIntNTy(llvm_module.getContext(), |
| (llvm_module.getPointerSize() == Module::Pointer64) ? 64 : 32); |
| |
| Constant *symbol_addr_int = ConstantInt::get(intptr_ty, symbol_addr, false); |
| |
| Value *symbol_addr_ptr = ConstantExpr::getIntToPtr(symbol_addr_int, symbol_type); |
| |
| if (log) |
| log->Printf("Replacing %s with %s", PrintValue(symbol).c_str(), PrintValue(symbol_addr_ptr).c_str()); |
| |
| symbol->replaceAllUsesWith(symbol_addr_ptr); |
| |
| return true; |
| } |
| |
| bool |
| IRForTarget::MaybeHandleCallArguments (Module &llvm_module, CallInst *Old) |
| { |
| lldb::LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS)); |
| |
| if (log) |
| log->Printf("MaybeHandleCallArguments(%s)", PrintValue(Old).c_str()); |
| |
| for (unsigned op_index = 0, num_ops = Old->getNumArgOperands(); |
| op_index < num_ops; |
| ++op_index) |
| if (!MaybeHandleVariable(llvm_module, Old->getArgOperand(op_index))) // conservatively believe that this is a store |
| { |
| if (m_error_stream) |
| m_error_stream->Printf("Internal error [IRForTarget]: Couldn't rewrite one of the arguments of a function call.\n"); |
| |
| return false; |
| } |
| |
| return true; |
| } |
| |
| bool |
| IRForTarget::MaybeHandleCall (Module &llvm_module, CallInst *llvm_call_inst) |
| { |
| lldb::LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS)); |
| |
| Function *fun = llvm_call_inst->getCalledFunction(); |
| |
| if (fun == NULL) |
| { |
| Value *val = llvm_call_inst->getCalledValue(); |
| |
| ConstantExpr *const_expr = dyn_cast<ConstantExpr>(val); |
| LoadInst *load_inst = dyn_cast<LoadInst>(val); |
| |
| if (const_expr && const_expr->getOpcode() == Instruction::BitCast) |
| { |
| fun = dyn_cast<Function>(const_expr->getOperand(0)); |
| |
| if (!fun) |
| { |
| if (m_error_stream) |
| m_error_stream->Printf("Internal error [IRForTarget]: Called entity is a cast of something not a function\n"); |
| |
| return false; |
| } |
| } |
| else if (const_expr && const_expr->getOpcode() == Instruction::IntToPtr) |
| { |
| return true; // already resolved |
| } |
| else if (load_inst) |
| { |
| return true; // virtual method call |
| } |
| else |
| { |
| if (m_error_stream) |
| m_error_stream->Printf("Internal error [IRForTarget]: Called entity is not a function\n"); |
| |
| return false; |
| } |
| } |
| |
| lldb_private::ConstString str; |
| |
| if (fun->isIntrinsic()) |
| { |
| Intrinsic::ID intrinsic_id = (Intrinsic::ID)fun->getIntrinsicID(); |
| |
| switch (intrinsic_id) |
| { |
| default: |
| if (log) |
| log->Printf("Unresolved intrinsic \"%s\"", Intrinsic::getName(intrinsic_id).c_str()); |
| |
| if (m_error_stream) |
| m_error_stream->Printf("Internal error [IRForTarget]: Call to unhandled compiler intrinsic '%s'\n", Intrinsic::getName(intrinsic_id).c_str()); |
| |
| return false; |
| case Intrinsic::memcpy: |
| { |
| static lldb_private::ConstString g_memcpy_str ("memcpy"); |
| str = g_memcpy_str; |
| } |
| break; |
| } |
| |
| if (log && str) |
| log->Printf("Resolved intrinsic name \"%s\"", str.GetCString()); |
| } |
| else |
| { |
| str.SetCStringWithLength (fun->getName().data(), fun->getName().size()); |
| } |
| |
| clang::NamedDecl *fun_decl = DeclForGlobalValue (llvm_module, fun); |
| lldb::addr_t fun_addr = LLDB_INVALID_ADDRESS; |
| Value **fun_value_ptr = NULL; |
| |
| if (fun_decl) |
| { |
| if (!m_decl_map->GetFunctionInfo (fun_decl, fun_value_ptr, fun_addr)) |
| { |
| fun_value_ptr = NULL; |
| |
| if (!m_decl_map->GetFunctionAddress (str, fun_addr)) |
| { |
| if (log) |
| log->Printf("Function \"%s\" had no address", str.GetCString()); |
| |
| if (m_error_stream) |
| m_error_stream->Printf("Error [IRForTarget]: Call to a function '%s' that is not present in the target\n", str.GetCString()); |
| |
| return false; |
| } |
| } |
| } |
| else |
| { |
| if (!m_decl_map->GetFunctionAddress (str, fun_addr)) |
| { |
| if (log) |
| log->Printf ("Metadataless function \"%s\" had no address", str.GetCString()); |
| |
| if (m_error_stream) |
| m_error_stream->Printf("Error [IRForTarget]: Call to a symbol-only function '%s' that is not present in the target\n", str.GetCString()); |
| |
| return false; |
| } |
| } |
| |
| if (log) |
| log->Printf("Found \"%s\" at 0x%llx", str.GetCString(), fun_addr); |
| |
| Value *fun_addr_ptr; |
| |
| if (!fun_value_ptr || !*fun_value_ptr) |
| { |
| const IntegerType *intptr_ty = Type::getIntNTy(llvm_module.getContext(), |
| (llvm_module.getPointerSize() == Module::Pointer64) ? 64 : 32); |
| const FunctionType *fun_ty = fun->getFunctionType(); |
| PointerType *fun_ptr_ty = PointerType::getUnqual(fun_ty); |
| Constant *fun_addr_int = ConstantInt::get(intptr_ty, fun_addr, false); |
| fun_addr_ptr = ConstantExpr::getIntToPtr(fun_addr_int, fun_ptr_ty); |
| |
| if (fun_value_ptr) |
| *fun_value_ptr = fun_addr_ptr; |
| } |
| |
| if (fun_value_ptr) |
| fun_addr_ptr = *fun_value_ptr; |
| |
| llvm_call_inst->setCalledFunction(fun_addr_ptr); |
| |
| ConstantArray *func_name = (ConstantArray*)ConstantArray::get(llvm_module.getContext(), str.GetCString()); |
| |
| Value *values[1]; |
| values[0] = func_name; |
| MDNode *func_metadata = MDNode::get(llvm_module.getContext(), values, 1); |
| |
| llvm_call_inst->setMetadata("lldb.call.realName", func_metadata); |
| |
| if (log) |
| log->Printf("Set metadata for %p [%d, \"%s\"]", llvm_call_inst, func_name->isString(), func_name->getAsString().c_str()); |
| |
| return true; |
| } |
| |
| bool |
| IRForTarget::ResolveCalls(Module &llvm_module, BasicBlock &basic_block) |
| { |
| ///////////////////////////////////////////////////////////////////////// |
| // Prepare the current basic block for execution in the remote process |
| // |
| |
| BasicBlock::iterator ii; |
| |
| for (ii = basic_block.begin(); |
| ii != basic_block.end(); |
| ++ii) |
| { |
| Instruction &inst = *ii; |
| |
| CallInst *call = dyn_cast<CallInst>(&inst); |
| |
| // MaybeHandleCall handles error reporting; we are silent here |
| if (call && !MaybeHandleCall(llvm_module, call)) |
| return false; |
| |
| // MaybeHandleCallArguments handles error reporting; we are silent here |
| if (call && !MaybeHandleCallArguments(llvm_module, call)) |
| return false; |
| } |
| |
| return true; |
| } |
| |
| bool |
| IRForTarget::ResolveExternals (Module &llvm_module, Function &llvm_function) |
| { |
| lldb::LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS)); |
| |
| for (Module::global_iterator global = llvm_module.global_begin(), end = llvm_module.global_end(); |
| global != end; |
| ++global) |
| { |
| if (log) |
| log->Printf("Examining %s, DeclForGlobalValue returns %p", |
| (*global).getName().str().c_str(), |
| DeclForGlobalValue(llvm_module, global)); |
| |
| if ((*global).getName().str().find("OBJC_IVAR") == 0) |
| { |
| if (!HandleSymbol(llvm_module, global)) |
| { |
| if (m_error_stream) |
| m_error_stream->Printf("Error [IRForTarget]: Couldn't find Objective-C indirect ivar symbol %s\n", (*global).getName().str().c_str()); |
| |
| return false; |
| } |
| } |
| else if (DeclForGlobalValue(llvm_module, global)) |
| { |
| if (!MaybeHandleVariable (llvm_module, global)) |
| { |
| if (m_error_stream) |
| m_error_stream->Printf("Internal error [IRForTarget]: Couldn't rewrite external variable %s\n", (*global).getName().str().c_str()); |
| |
| return false; |
| } |
| } |
| } |
| |
| return true; |
| } |
| |
| static bool isGuardVariableRef(Value *V) |
| { |
| Constant *Old; |
| |
| if (!(Old = dyn_cast<Constant>(V))) |
| return false; |
| |
| ConstantExpr *CE; |
| |
| if ((CE = dyn_cast<ConstantExpr>(V))) |
| { |
| if (CE->getOpcode() != Instruction::BitCast) |
| return false; |
| |
| Old = CE->getOperand(0); |
| } |
| |
| GlobalVariable *GV = dyn_cast<GlobalVariable>(Old); |
| |
| if (!GV || !GV->hasName() || !GV->getName().startswith("_ZGV")) |
| return false; |
| |
| return true; |
| } |
| |
| static void TurnGuardLoadIntoZero(Instruction* guard_load, Module &llvm_module) |
| { |
| Constant* zero(ConstantInt::get(Type::getInt8Ty(llvm_module.getContext()), 0, true)); |
| |
| Value::use_iterator ui; |
| |
| for (ui = guard_load->use_begin(); |
| ui != guard_load->use_end(); |
| ++ui) |
| { |
| if (isa<Constant>(*ui)) |
| { |
| // do nothing for the moment |
| } |
| else |
| { |
| ui->replaceUsesOfWith(guard_load, zero); |
| } |
| } |
| |
| guard_load->eraseFromParent(); |
| } |
| |
| static void ExciseGuardStore(Instruction* guard_store) |
| { |
| guard_store->eraseFromParent(); |
| } |
| |
| bool |
| IRForTarget::RemoveGuards(Module &llvm_module, BasicBlock &basic_block) |
| { |
| /////////////////////////////////////////////////////// |
| // Eliminate any reference to guard variables found. |
| // |
| |
| BasicBlock::iterator ii; |
| |
| typedef SmallVector <Instruction*, 2> InstrList; |
| typedef InstrList::iterator InstrIterator; |
| |
| InstrList guard_loads; |
| InstrList guard_stores; |
| |
| for (ii = basic_block.begin(); |
| ii != basic_block.end(); |
| ++ii) |
| { |
| Instruction &inst = *ii; |
| |
| if (LoadInst *load = dyn_cast<LoadInst>(&inst)) |
| if (isGuardVariableRef(load->getPointerOperand())) |
| guard_loads.push_back(&inst); |
| |
| if (StoreInst *store = dyn_cast<StoreInst>(&inst)) |
| if (isGuardVariableRef(store->getPointerOperand())) |
| guard_stores.push_back(&inst); |
| } |
| |
| InstrIterator iter; |
| |
| for (iter = guard_loads.begin(); |
| iter != guard_loads.end(); |
| ++iter) |
| TurnGuardLoadIntoZero(*iter, llvm_module); |
| |
| for (iter = guard_stores.begin(); |
| iter != guard_stores.end(); |
| ++iter) |
| ExciseGuardStore(*iter); |
| |
| return true; |
| } |
| |
| // This function does not report errors; its callers are responsible. |
| bool |
| IRForTarget::UnfoldConstant(Constant *old_constant, Value *new_constant, Instruction *first_entry_inst) |
| { |
| lldb::LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS)); |
| |
| Value::use_iterator ui; |
| |
| SmallVector<User*, 16> users; |
| |
| // We do this because the use list might change, invalidating our iterator. |
| // Much better to keep a work list ourselves. |
| for (ui = old_constant->use_begin(); |
| ui != old_constant->use_end(); |
| ++ui) |
| users.push_back(*ui); |
| |
| for (int i = 0; |
| i < users.size(); |
| ++i) |
| { |
| User *user = users[i]; |
| |
| if (Constant *constant = dyn_cast<Constant>(user)) |
| { |
| // synthesize a new non-constant equivalent of the constant |
| |
| if (ConstantExpr *constant_expr = dyn_cast<ConstantExpr>(constant)) |
| { |
| switch (constant_expr->getOpcode()) |
| { |
| default: |
| if (log) |
| log->Printf("Unhandled constant expression type: \"%s\"", PrintValue(constant_expr).c_str()); |
| return false; |
| case Instruction::BitCast: |
| { |
| // UnaryExpr |
| // OperandList[0] is value |
| |
| Value *s = constant_expr->getOperand(0); |
| |
| if (s == old_constant) |
| s = new_constant; |
| |
| BitCastInst *bit_cast(new BitCastInst(s, old_constant->getType(), "", first_entry_inst)); |
| |
| UnfoldConstant(constant_expr, bit_cast, first_entry_inst); |
| } |
| break; |
| case Instruction::GetElementPtr: |
| { |
| // GetElementPtrConstantExpr |
| // OperandList[0] is base |
| // OperandList[1]... are indices |
| |
| Value *ptr = constant_expr->getOperand(0); |
| |
| if (ptr == old_constant) |
| ptr = new_constant; |
| |
| SmallVector<Value*, 16> indices; |
| |
| unsigned operand_index; |
| unsigned num_operands = constant_expr->getNumOperands(); |
| |
| for (operand_index = 1; |
| operand_index < num_operands; |
| ++operand_index) |
| { |
| Value *operand = constant_expr->getOperand(operand_index); |
| |
| if (operand == old_constant) |
| operand = new_constant; |
| |
| indices.push_back(operand); |
| } |
| |
| GetElementPtrInst *get_element_ptr(GetElementPtrInst::Create(ptr, indices.begin(), indices.end(), "", first_entry_inst)); |
| |
| UnfoldConstant(constant_expr, get_element_ptr, first_entry_inst); |
| } |
| break; |
| } |
| } |
| else |
| { |
| if (log) |
| log->Printf("Unhandled constant type: \"%s\"", PrintValue(constant).c_str()); |
| return false; |
| } |
| } |
| else |
| { |
| // simple fall-through case for non-constants |
| user->replaceUsesOfWith(old_constant, new_constant); |
| } |
| } |
| |
| return true; |
| } |
| |
| bool |
| IRForTarget::ReplaceVariables (Module &llvm_module, Function &llvm_function) |
| { |
| if (!m_resolve_vars) |
| return true; |
| |
| lldb::LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS)); |
| |
| m_decl_map->DoStructLayout(); |
| |
| if (log) |
| log->Printf("Element arrangement:"); |
| |
| uint32_t num_elements; |
| uint32_t element_index; |
| |
| size_t size; |
| off_t alignment; |
| |
| if (!m_decl_map->GetStructInfo (num_elements, size, alignment)) |
| return false; |
| |
| Function::arg_iterator iter(llvm_function.getArgumentList().begin()); |
| |
| if (iter == llvm_function.getArgumentList().end()) |
| { |
| if (m_error_stream) |
| m_error_stream->Printf("Internal error [IRForTarget]: Wrapper takes no arguments (should take at least a struct pointer)"); |
| |
| return false; |
| } |
| |
| Argument *argument = iter; |
| |
| if (argument->getName().equals("this")) |
| { |
| ++iter; |
| |
| if (iter == llvm_function.getArgumentList().end()) |
| { |
| if (m_error_stream) |
| m_error_stream->Printf("Internal error [IRForTarget]: Wrapper takes only 'this' argument (should take a struct pointer too)"); |
| |
| return false; |
| } |
| |
| argument = iter; |
| } |
| else if (argument->getName().equals("self")) |
| { |
| ++iter; |
| |
| if (iter == llvm_function.getArgumentList().end()) |
| { |
| if (m_error_stream) |
| m_error_stream->Printf("Internal error [IRForTarget]: Wrapper takes only 'self' argument (should take '_cmd' and a struct pointer too)"); |
| |
| return false; |
| } |
| |
| if (!iter->getName().equals("_cmd")) |
| { |
| if (m_error_stream) |
| m_error_stream->Printf("Internal error [IRForTarget]: Wrapper takes '%s' after 'self' argument (should take '_cmd')", iter->getName().str().c_str()); |
| |
| return false; |
| } |
| |
| ++iter; |
| |
| if (iter == llvm_function.getArgumentList().end()) |
| { |
| if (m_error_stream) |
| m_error_stream->Printf("Internal error [IRForTarget]: Wrapper takes only 'self' and '_cmd' arguments (should take a struct pointer too)"); |
| |
| return false; |
| } |
| |
| argument = iter; |
| } |
| |
| if (!argument->getName().equals("$__lldb_arg")) |
| { |
| if (m_error_stream) |
| m_error_stream->Printf("Internal error [IRForTarget]: Wrapper takes an argument named '%s' instead of the struct pointer", argument->getName().str().c_str()); |
| |
| return false; |
| } |
| |
| if (log) |
| log->Printf("Arg: \"%s\"", PrintValue(argument).c_str()); |
| |
| BasicBlock &entry_block(llvm_function.getEntryBlock()); |
| Instruction *FirstEntryInstruction(entry_block.getFirstNonPHIOrDbg()); |
| |
| if (!FirstEntryInstruction) |
| { |
| if (m_error_stream) |
| m_error_stream->Printf("Internal error [IRForTarget]: Couldn't find the first instruction in the wrapper for use in rewriting"); |
| |
| return false; |
| } |
| |
| LLVMContext &context(llvm_module.getContext()); |
| const IntegerType *offset_type(Type::getInt32Ty(context)); |
| |
| if (!offset_type) |
| { |
| if (m_error_stream) |
| m_error_stream->Printf("Internal error [IRForTarget]: Couldn't produce an offset type"); |
| |
| return false; |
| } |
| |
| for (element_index = 0; element_index < num_elements; ++element_index) |
| { |
| const clang::NamedDecl *decl; |
| Value *value; |
| off_t offset; |
| lldb_private::ConstString name; |
| |
| if (!m_decl_map->GetStructElement (decl, value, offset, name, element_index)) |
| { |
| if (m_error_stream) |
| m_error_stream->Printf("Internal error [IRForTarget]: Structure information is incomplete"); |
| |
| return false; |
| } |
| |
| if (log) |
| log->Printf(" \"%s\" [\"%s\"] (\"%s\") placed at %d", |
| value->getName().str().c_str(), |
| name.GetCString(), |
| PrintValue(value, true).c_str(), |
| offset); |
| |
| ConstantInt *offset_int(ConstantInt::getSigned(offset_type, offset)); |
| GetElementPtrInst *get_element_ptr = GetElementPtrInst::Create(argument, offset_int, "", FirstEntryInstruction); |
| |
| Value *replacement; |
| |
| // Per the comment at ASTResultSynthesizer::SynthesizeBodyResult, in cases where the result |
| // variable is an rvalue, we have to synthesize a dereference of the appropriate structure |
| // entry in order to produce the static variable that the AST thinks it is accessing. |
| if (name == m_result_name && !m_result_is_pointer) |
| { |
| BitCastInst *bit_cast = new BitCastInst(get_element_ptr, value->getType()->getPointerTo(), "", FirstEntryInstruction); |
| |
| LoadInst *load = new LoadInst(bit_cast, "", FirstEntryInstruction); |
| |
| replacement = load; |
| } |
| else |
| { |
| BitCastInst *bit_cast = new BitCastInst(get_element_ptr, value->getType(), "", FirstEntryInstruction); |
| |
| replacement = bit_cast; |
| } |
| |
| if (Constant *constant = dyn_cast<Constant>(value)) |
| UnfoldConstant(constant, replacement, FirstEntryInstruction); |
| else |
| value->replaceAllUsesWith(replacement); |
| |
| if (GlobalVariable *var = dyn_cast<GlobalVariable>(value)) |
| var->eraseFromParent(); |
| } |
| |
| if (log) |
| log->Printf("Total structure [align %d, size %d]", alignment, size); |
| |
| return true; |
| } |
| |
| bool |
| IRForTarget::runOnModule (Module &llvm_module) |
| { |
| lldb::LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS)); |
| |
| Function* function = llvm_module.getFunction(StringRef(m_func_name.c_str())); |
| |
| if (!function) |
| { |
| if (log) |
| log->Printf("Couldn't find \"%s()\" in the module", m_func_name.c_str()); |
| |
| if (m_error_stream) |
| m_error_stream->Printf("Internal error [IRForTarget]: Couldn't find wrapper '%s' in the mdoule", m_func_name.c_str()); |
| |
| return false; |
| } |
| |
| Function::iterator bbi; |
| |
| m_has_side_effects = HasSideEffects(llvm_module, *function); |
| |
| //////////////////////////////////////////////////////////// |
| // Replace $__lldb_expr_result with a persistent variable |
| // |
| |
| if (!CreateResultVariable(llvm_module, *function)) |
| { |
| if (log) |
| log->Printf("CreateResultVariable() failed"); |
| |
| // CreateResultVariable() reports its own errors, so we don't do so here |
| |
| return false; |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| // Fix all Objective-C constant strings to use NSStringWithCString:encoding: |
| // |
| |
| if (!RewriteObjCConstStrings(llvm_module, *function)) |
| { |
| if (log) |
| log->Printf("RewriteObjCConstStrings() failed"); |
| |
| // RewriteObjCConstStrings() reports its own errors, so we don't do so here |
| |
| return false; |
| } |
| |
| ////////////////////////////////// |
| // Run basic-block level passes |
| // |
| |
| for (bbi = function->begin(); |
| bbi != function->end(); |
| ++bbi) |
| { |
| if (!RemoveGuards(llvm_module, *bbi)) |
| { |
| if (log) |
| log->Printf("RemoveGuards() failed"); |
| |
| // RemoveGuards() reports its own errors, so we don't do so here |
| |
| return false; |
| } |
| |
| if (!RewritePersistentAllocs(llvm_module, *bbi)) |
| { |
| if (log) |
| log->Printf("RewritePersistentAllocs() failed"); |
| |
| // RewritePersistentAllocs() reports its own errors, so we don't do so here |
| |
| return false; |
| } |
| |
| if (!RewriteObjCSelectors(llvm_module, *bbi)) |
| { |
| if (log) |
| log->Printf("RewriteObjCSelectors() failed"); |
| |
| // RewriteObjCSelectors() reports its own errors, so we don't do so here |
| |
| return false; |
| } |
| |
| if (!ResolveCalls(llvm_module, *bbi)) |
| { |
| if (log) |
| log->Printf("ResolveCalls() failed"); |
| |
| // ResolveCalls() reports its own errors, so we don't do so here |
| |
| return false; |
| } |
| } |
| |
| /////////////////////////////// |
| // Run function-level passes |
| // |
| |
| if (!ResolveExternals(llvm_module, *function)) |
| { |
| if (log) |
| log->Printf("ResolveExternals() failed"); |
| |
| // ResolveExternals() reports its own errors, so we don't do so here |
| |
| return false; |
| } |
| |
| if (!ReplaceVariables(llvm_module, *function)) |
| { |
| if (log) |
| log->Printf("ReplaceVariables() failed"); |
| |
| // ReplaceVariables() reports its own errors, so we don't do so here |
| |
| return false; |
| } |
| |
| if (log) |
| { |
| std::string s; |
| raw_string_ostream oss(s); |
| |
| llvm_module.print(oss, NULL); |
| |
| oss.flush(); |
| |
| log->Printf("Module after preparing for execution: \n\"%s\"", s.c_str()); |
| } |
| |
| return true; |
| } |
| |
| void |
| IRForTarget::assignPassManager (PMStack &pass_mgr_stack, PassManagerType pass_mgr_type) |
| { |
| } |
| |
| PassManagerType |
| IRForTarget::getPotentialPassManagerType() const |
| { |
| return PMT_ModulePassManager; |
| } |
