Files
clang-p2996/lldb/source/Expression/ClangUserExpression.cpp
Greg Clayton d4a2b37091 Huge memory and performance improvements in the DWARF parser.
Address ranges are now split up into two different tables: 
- one in DWARFDebugInfo that is compile unit specific
- one in each DWARFCompileUnit that has exact function DIE offsets

This helps keep the size of the aranges down since the main table will get
uniqued and sorted and have consecutive ranges merged. We then only parse the
compile unit one on demand once we have determined that a compile unit contains
the address in question. We also now use the .debug_aranges section if there 
is one instead of always indexing the DWARF manually.

NameToDIE now uses a UniqueCStringMap<dw_offset> map instead of a std::map.
std::map is very bulky as each node has 3 pointers and the key and value types.
This gets our NameToDIE entry down to 12 bytes each instead of 48 which saves
us a lot of memory when we have very large DWARF.

DWARFDebugAranges now has a smaller footprint for each range it contains to 
save on memory.

llvm-svn: 139557
2011-09-12 23:21:58 +00:00

742 lines
27 KiB
C++

//===-- ClangUserExpression.cpp ---------------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// C Includes
#include <stdio.h>
#if HAVE_SYS_TYPES_H
# include <sys/types.h>
#endif
// C++ Includes
#include <cstdlib>
#include <string>
#include <map>
#include "lldb/Core/ConstString.h"
#include "lldb/Core/Log.h"
#include "lldb/Core/StreamFile.h"
#include "lldb/Core/StreamString.h"
#include "lldb/Core/ValueObjectConstResult.h"
#include "lldb/Expression/ASTResultSynthesizer.h"
#include "lldb/Expression/ClangExpressionDeclMap.h"
#include "lldb/Expression/ClangExpressionParser.h"
#include "lldb/Expression/ClangFunction.h"
#include "lldb/Expression/ClangUserExpression.h"
#include "lldb/Host/Host.h"
#include "lldb/Symbol/VariableList.h"
#include "lldb/Target/ExecutionContext.h"
#include "lldb/Target/Process.h"
#include "lldb/Target/StackFrame.h"
#include "lldb/Target/Target.h"
#include "lldb/Target/ThreadPlan.h"
#include "lldb/Target/ThreadPlanCallUserExpression.h"
#include "clang/AST/DeclCXX.h"
#include "clang/AST/DeclObjC.h"
using namespace lldb_private;
ClangUserExpression::ClangUserExpression (const char *expr,
const char *expr_prefix) :
ClangExpression (),
m_expr_text (expr),
m_expr_prefix (expr_prefix ? expr_prefix : ""),
m_transformed_text (),
m_desired_type (NULL, NULL),
m_cplusplus (false),
m_objectivec (false),
m_needs_object_ptr (false),
m_const_object (false),
m_const_result (),
m_target (NULL)
{
}
ClangUserExpression::~ClangUserExpression ()
{
}
clang::ASTConsumer *
ClangUserExpression::ASTTransformer (clang::ASTConsumer *passthrough)
{
ClangASTContext *clang_ast_context = m_target->GetScratchClangASTContext();
if (!clang_ast_context)
return NULL;
return new ASTResultSynthesizer(passthrough,
m_desired_type,
*m_target->GetScratchClangASTContext()->getASTContext(),
m_target->GetPersistentVariables());
}
void
ClangUserExpression::ScanContext(ExecutionContext &exe_ctx)
{
m_target = exe_ctx.target;
if (!exe_ctx.frame)
return;
SymbolContext sym_ctx = exe_ctx.frame->GetSymbolContext(lldb::eSymbolContextFunction);
if (!sym_ctx.function)
return;
clang::DeclContext *decl_context;
if (sym_ctx.block && sym_ctx.block->GetInlinedFunctionInfo())
decl_context = sym_ctx.block->GetClangDeclContextForInlinedFunction();
else
decl_context = sym_ctx.function->GetClangDeclContext();
if (!decl_context)
return;
if (clang::CXXMethodDecl *method_decl = llvm::dyn_cast<clang::CXXMethodDecl>(decl_context))
{
if (method_decl->isInstance())
{
m_cplusplus = true;
do {
clang::QualType this_type = method_decl->getThisType(decl_context->getParentASTContext());
const clang::PointerType *this_pointer_type = llvm::dyn_cast<clang::PointerType>(this_type.getTypePtr());
if (!this_pointer_type)
break;
clang::QualType this_pointee_type = this_pointer_type->getPointeeType();
} while (0);
}
}
else if (clang::ObjCMethodDecl *method_decl = llvm::dyn_cast<clang::ObjCMethodDecl>(decl_context))
{
if (method_decl->isInstanceMethod())
m_objectivec = true;
}
}
// This is a really nasty hack, meant to fix Objective-C expressions of the form
// (int)[myArray count]. Right now, because the type information for count is
// not available, [myArray count] returns id, which can't be directly cast to
// int without causing a clang error.
static void
ApplyObjcCastHack(std::string &expr)
{
#define OBJC_CAST_HACK_FROM "(int)["
#define OBJC_CAST_HACK_TO "(int)(long long)["
size_t from_offset;
while ((from_offset = expr.find(OBJC_CAST_HACK_FROM)) != expr.npos)
expr.replace(from_offset, sizeof(OBJC_CAST_HACK_FROM) - 1, OBJC_CAST_HACK_TO);
#undef OBJC_CAST_HACK_TO
#undef OBJC_CAST_HACK_FROM
}
// Another hack, meant to allow use of unichar despite it not being available in
// the type information. Although we could special-case it in type lookup,
// hopefully we'll figure out a way to #include the same environment as is
// present in the original source file rather than try to hack specific type
// definitions in as needed.
static void
ApplyUnicharHack(std::string &expr)
{
#define UNICHAR_HACK_FROM "unichar"
#define UNICHAR_HACK_TO "unsigned short"
size_t from_offset;
while ((from_offset = expr.find(UNICHAR_HACK_FROM)) != expr.npos)
expr.replace(from_offset, sizeof(UNICHAR_HACK_FROM) - 1, UNICHAR_HACK_TO);
#undef UNICHAR_HACK_TO
#undef UNICHAR_HACK_FROM
}
bool
ClangUserExpression::Parse (Stream &error_stream,
ExecutionContext &exe_ctx,
TypeFromUser desired_type,
bool keep_result_in_memory)
{
lldb::LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS));
ScanContext(exe_ctx);
StreamString m_transformed_stream;
////////////////////////////////////
// Generate the expression
//
ApplyObjcCastHack(m_expr_text);
//ApplyUnicharHack(m_expr_text);
if (m_cplusplus)
{
m_transformed_stream.Printf("%s \n"
"typedef unsigned short unichar; \n"
"void \n"
"$__lldb_class::%s(void *$__lldb_arg) %s\n"
"{ \n"
" %s; \n"
"} \n",
m_expr_prefix.c_str(),
FunctionName(),
(m_const_object ? "const" : ""),
m_expr_text.c_str());
m_needs_object_ptr = true;
}
else if (m_objectivec)
{
const char *function_name = FunctionName();
m_transformed_stream.Printf("%s \n"
"typedef unsigned short unichar; \n"
"@interface $__lldb_objc_class ($__lldb_category) \n"
"-(void)%s:(void *)$__lldb_arg; \n"
"@end \n"
"@implementation $__lldb_objc_class ($__lldb_category) \n"
"-(void)%s:(void *)$__lldb_arg \n"
"{ \n"
" %s; \n"
"} \n"
"@end \n",
m_expr_prefix.c_str(),
function_name,
function_name,
m_expr_text.c_str());
m_needs_object_ptr = true;
}
else
{
m_transformed_stream.Printf("%s \n"
"typedef unsigned short unichar;\n"
"void \n"
"%s(void *$__lldb_arg) \n"
"{ \n"
" %s; \n"
"} \n",
m_expr_prefix.c_str(),
FunctionName(),
m_expr_text.c_str());
}
m_transformed_text = m_transformed_stream.GetData();
if (log)
log->Printf("Parsing the following code:\n%s", m_transformed_text.c_str());
////////////////////////////////////
// Set up the target and compiler
//
Target *target = exe_ctx.target;
if (!target)
{
error_stream.PutCString ("error: invalid target\n");
return false;
}
//////////////////////////
// Parse the expression
//
m_desired_type = desired_type;
m_expr_decl_map.reset(new ClangExpressionDeclMap(keep_result_in_memory));
if (!m_expr_decl_map->WillParse(exe_ctx))
{
error_stream.PutCString ("error: current process state is unsuitable for expression parsing\n");
return false;
}
ClangExpressionParser parser(exe_ctx.process, *this);
unsigned num_errors = parser.Parse (error_stream);
if (num_errors)
{
error_stream.Printf ("error: %d errors parsing expression\n", num_errors);
m_expr_decl_map->DidParse();
return false;
}
///////////////////////////////////////////////
// Convert the output of the parser to DWARF
//
m_dwarf_opcodes.reset(new StreamString);
m_dwarf_opcodes->SetByteOrder (lldb::endian::InlHostByteOrder());
m_dwarf_opcodes->GetFlags ().Set (Stream::eBinary);
m_local_variables.reset(new ClangExpressionVariableList());
Error dwarf_error = parser.MakeDWARF ();
if (dwarf_error.Success())
{
if (log)
log->Printf("Code can be interpreted.");
m_expr_decl_map->DidParse();
return true;
}
//////////////////////////////////
// JIT the output of the parser
//
m_dwarf_opcodes.reset();
m_data_allocator.reset(new ProcessDataAllocator(*exe_ctx.process));
Error jit_error = parser.MakeJIT (m_jit_alloc, m_jit_start_addr, m_jit_end_addr, exe_ctx, m_data_allocator.get(), m_const_result, true);
if (log)
{
StreamString dump_string;
m_data_allocator->Dump(dump_string);
log->Printf("Data buffer contents:\n%s", dump_string.GetString().c_str());
}
m_expr_decl_map->DidParse();
if (jit_error.Success())
{
if (exe_ctx.process && m_jit_alloc != LLDB_INVALID_ADDRESS)
m_jit_process_sp = exe_ctx.process->GetSP();
return true;
}
else
{
const char *error_cstr = jit_error.AsCString();
if (error_cstr && error_cstr[0])
error_stream.Printf ("error: %s\n", error_cstr);
else
error_stream.Printf ("error: expression can't be interpreted or run\n", num_errors);
return false;
}
}
bool
ClangUserExpression::PrepareToExecuteJITExpression (Stream &error_stream,
ExecutionContext &exe_ctx,
lldb::addr_t &struct_address,
lldb::addr_t &object_ptr,
lldb::addr_t &cmd_ptr)
{
lldb::LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS));
if (m_jit_start_addr != LLDB_INVALID_ADDRESS)
{
Error materialize_error;
if (m_needs_object_ptr)
{
ConstString object_name;
if (m_cplusplus)
{
object_name.SetCString("this");
}
else if (m_objectivec)
{
object_name.SetCString("self");
}
else
{
error_stream.Printf("Need object pointer but don't know the language\n");
return false;
}
if (!(m_expr_decl_map->GetObjectPointer(object_ptr, object_name, exe_ctx, materialize_error)))
{
error_stream.Printf("Couldn't get required object pointer: %s\n", materialize_error.AsCString());
return false;
}
if (m_objectivec)
{
ConstString cmd_name("_cmd");
if (!(m_expr_decl_map->GetObjectPointer(cmd_ptr, cmd_name, exe_ctx, materialize_error, true)))
{
error_stream.Printf("Couldn't get required object pointer: %s\n", materialize_error.AsCString());
return false;
}
}
}
if (!m_expr_decl_map->Materialize(exe_ctx, struct_address, materialize_error))
{
error_stream.Printf("Couldn't materialize struct: %s\n", materialize_error.AsCString());
return false;
}
#if 0
// jingham: look here
StreamFile logfile ("/tmp/exprs.txt", "a");
logfile.Printf("0x%16.16llx: thread = 0x%4.4x, expr = '%s'\n", m_jit_start_addr, exe_ctx.thread ? exe_ctx.thread->GetID() : -1, m_expr_text.c_str());
#endif
if (log)
{
log->Printf("-- [ClangUserExpression::PrepareToExecuteJITExpression] Materializing for execution --");
log->Printf(" Function address : 0x%llx", (uint64_t)m_jit_start_addr);
if (m_needs_object_ptr)
log->Printf(" Object pointer : 0x%llx", (uint64_t)object_ptr);
log->Printf(" Structure address : 0x%llx", (uint64_t)struct_address);
StreamString args;
Error dump_error;
if (struct_address)
{
if (!m_expr_decl_map->DumpMaterializedStruct(exe_ctx, args, dump_error))
{
log->Printf(" Couldn't extract variable values : %s", dump_error.AsCString("unknown error"));
}
else
{
log->Printf(" Structure contents:\n%s", args.GetData());
}
}
}
}
return true;
}
ThreadPlan *
ClangUserExpression::GetThreadPlanToExecuteJITExpression (Stream &error_stream,
ExecutionContext &exe_ctx)
{
lldb::addr_t struct_address;
lldb::addr_t object_ptr = 0;
lldb::addr_t cmd_ptr = 0;
PrepareToExecuteJITExpression (error_stream, exe_ctx, struct_address, object_ptr, cmd_ptr);
// FIXME: This should really return a ThreadPlanCallUserExpression, in order to make sure that we don't release the
// ClangUserExpression resources before the thread plan finishes execution in the target. But because we are
// forcing unwind_on_error to be true here, in practical terms that can't happen.
return ClangFunction::GetThreadPlanToCallFunction (exe_ctx,
m_jit_start_addr,
struct_address,
error_stream,
true,
true,
(m_needs_object_ptr ? &object_ptr : NULL),
(m_needs_object_ptr && m_objectivec) ? &cmd_ptr : NULL);
}
bool
ClangUserExpression::FinalizeJITExecution (Stream &error_stream,
ExecutionContext &exe_ctx,
lldb::ClangExpressionVariableSP &result,
lldb::addr_t function_stack_pointer)
{
Error expr_error;
lldb::LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS));
if (log)
{
log->Printf("-- [ClangUserExpression::FinalizeJITExecution] Dematerializing after execution --");
StreamString args;
Error dump_error;
if (!m_expr_decl_map->DumpMaterializedStruct(exe_ctx, args, dump_error))
{
log->Printf(" Couldn't extract variable values : %s", dump_error.AsCString("unknown error"));
}
else
{
log->Printf(" Structure contents:\n%s", args.GetData());
}
}
lldb::addr_t function_stack_bottom = function_stack_pointer - Host::GetPageSize();
if (!m_expr_decl_map->Dematerialize(exe_ctx, result, function_stack_pointer, function_stack_bottom, expr_error))
{
error_stream.Printf ("Couldn't dematerialize struct : %s\n", expr_error.AsCString("unknown error"));
return false;
}
return true;
}
ExecutionResults
ClangUserExpression::Execute (Stream &error_stream,
ExecutionContext &exe_ctx,
bool discard_on_error,
ClangUserExpression::ClangUserExpressionSP &shared_ptr_to_me,
lldb::ClangExpressionVariableSP &result)
{
// The expression log is quite verbose, and if you're just tracking the execution of the
// expression, it's quite convenient to have these logs come out with the STEP log as well.
lldb::LogSP log(lldb_private::GetLogIfAnyCategoriesSet (LIBLLDB_LOG_EXPRESSIONS | LIBLLDB_LOG_STEP));
if (m_dwarf_opcodes.get())
{
// TODO execute the JITted opcodes
error_stream.Printf("We don't currently support executing DWARF expressions");
return eExecutionSetupError;
}
else if (m_jit_start_addr != LLDB_INVALID_ADDRESS)
{
lldb::addr_t struct_address;
lldb::addr_t object_ptr = 0;
lldb::addr_t cmd_ptr = 0;
if (!PrepareToExecuteJITExpression (error_stream, exe_ctx, struct_address, object_ptr, cmd_ptr))
return eExecutionSetupError;
const bool stop_others = true;
const bool try_all_threads = true;
Address wrapper_address (NULL, m_jit_start_addr);
lldb::ThreadPlanSP call_plan_sp(new ThreadPlanCallUserExpression (*(exe_ctx.thread),
wrapper_address,
struct_address,
stop_others,
discard_on_error,
(m_needs_object_ptr ? &object_ptr : NULL),
((m_needs_object_ptr && m_objectivec) ? &cmd_ptr : NULL),
shared_ptr_to_me));
if (call_plan_sp == NULL || !call_plan_sp->ValidatePlan (NULL))
return eExecutionSetupError;
lldb::addr_t function_stack_pointer = static_cast<ThreadPlanCallFunction *>(call_plan_sp.get())->GetFunctionStackPointer();
call_plan_sp->SetPrivate(true);
uint32_t single_thread_timeout_usec = 500000;
if (log)
log->Printf("-- [ClangUserExpression::Execute] Execution of expression begins --");
ExecutionResults execution_result = exe_ctx.process->RunThreadPlan (exe_ctx,
call_plan_sp,
stop_others,
try_all_threads,
discard_on_error,
single_thread_timeout_usec,
error_stream);
if (log)
log->Printf("-- [ClangUserExpression::Execute] Execution of expression completed --");
if (execution_result == eExecutionInterrupted)
{
const char *error_desc = NULL;
if (call_plan_sp)
{
lldb::StopInfoSP real_stop_info_sp = call_plan_sp->GetRealStopInfo();
if (real_stop_info_sp)
error_desc = real_stop_info_sp->GetDescription();
}
if (error_desc)
error_stream.Printf ("Execution was interrupted, reason: %s.", error_desc);
else
error_stream.Printf ("Execution was interrupted.", error_desc);
if (discard_on_error)
error_stream.Printf ("\nThe process has been returned to the state before execution.");
else
error_stream.Printf ("\nThe process has been left at the point where it was interrupted.");
return execution_result;
}
else if (execution_result != eExecutionCompleted)
{
error_stream.Printf ("Couldn't execute function; result was %s\n", Process::ExecutionResultAsCString (execution_result));
return execution_result;
}
if (FinalizeJITExecution (error_stream, exe_ctx, result, function_stack_pointer))
return eExecutionCompleted;
else
return eExecutionSetupError;
}
else
{
error_stream.Printf("Expression can't be run; neither DWARF nor a JIT compiled function is present");
return eExecutionSetupError;
}
}
StreamString &
ClangUserExpression::DwarfOpcodeStream ()
{
if (!m_dwarf_opcodes.get())
m_dwarf_opcodes.reset(new StreamString());
return *m_dwarf_opcodes.get();
}
ExecutionResults
ClangUserExpression::Evaluate (ExecutionContext &exe_ctx,
bool discard_on_error,
const char *expr_cstr,
const char *expr_prefix,
lldb::ValueObjectSP &result_valobj_sp)
{
Error error;
return EvaluateWithError (exe_ctx, discard_on_error, expr_cstr, expr_prefix, result_valobj_sp, error);
}
ExecutionResults
ClangUserExpression::EvaluateWithError (ExecutionContext &exe_ctx,
bool discard_on_error,
const char *expr_cstr,
const char *expr_prefix,
lldb::ValueObjectSP &result_valobj_sp,
Error &error)
{
lldb::LogSP log(lldb_private::GetLogIfAnyCategoriesSet (LIBLLDB_LOG_EXPRESSIONS | LIBLLDB_LOG_STEP));
ExecutionResults execution_results = eExecutionSetupError;
if (exe_ctx.process == NULL || exe_ctx.process->GetState() != lldb::eStateStopped)
{
error.SetErrorString ("must have a stopped process to evaluate expressions.");
result_valobj_sp = ValueObjectConstResult::Create (NULL, error);
return eExecutionSetupError;
}
if (!exe_ctx.process->GetDynamicCheckers())
{
if (log)
log->Printf("== [ClangUserExpression::Evaluate] Installing dynamic checkers ==");
DynamicCheckerFunctions *dynamic_checkers = new DynamicCheckerFunctions();
StreamString install_errors;
if (!dynamic_checkers->Install(install_errors, exe_ctx))
{
if (install_errors.GetString().empty())
error.SetErrorString ("couldn't install checkers, unknown error");
else
error.SetErrorString (install_errors.GetString().c_str());
result_valobj_sp = ValueObjectConstResult::Create (NULL, error);
return eExecutionSetupError;
}
exe_ctx.process->SetDynamicCheckers(dynamic_checkers);
if (log)
log->Printf("== [ClangUserExpression::Evaluate] Finished installing dynamic checkers ==");
}
ClangUserExpressionSP user_expression_sp (new ClangUserExpression (expr_cstr, expr_prefix));
StreamString error_stream;
if (log)
log->Printf("== [ClangUserExpression::Evaluate] Parsing expression %s ==", expr_cstr);
if (!user_expression_sp->Parse (error_stream, exe_ctx, TypeFromUser(NULL, NULL), true))
{
if (error_stream.GetString().empty())
error.SetErrorString ("expression failed to parse, unknown error");
else
error.SetErrorString (error_stream.GetString().c_str());
}
else
{
lldb::ClangExpressionVariableSP expr_result;
if (user_expression_sp->m_const_result.get())
{
if (log)
log->Printf("== [ClangUserExpression::Evaluate] Expression evaluated as a constant ==");
result_valobj_sp = user_expression_sp->m_const_result->GetValueObject();
execution_results = eExecutionCompleted;
}
else
{
error_stream.GetString().clear();
if (log)
log->Printf("== [ClangUserExpression::Evaluate] Executing expression ==");
execution_results = user_expression_sp->Execute (error_stream,
exe_ctx,
discard_on_error,
user_expression_sp,
expr_result);
if (execution_results != eExecutionCompleted)
{
if (log)
log->Printf("== [ClangUserExpression::Evaluate] Execution completed abnormally ==");
if (error_stream.GetString().empty())
error.SetErrorString ("expression failed to execute, unknown error");
else
error.SetErrorString (error_stream.GetString().c_str());
}
else
{
if (expr_result)
{
result_valobj_sp = expr_result->GetValueObject();
if (log)
log->Printf("== [ClangUserExpression::Evaluate] Execution completed normally with result %s ==", result_valobj_sp->GetValueAsCString());
}
else
{
if (log)
log->Printf("== [ClangUserExpression::Evaluate] Execution completed normally with no result ==");
error.SetError(ClangUserExpression::kNoResult, lldb::eErrorTypeGeneric);
}
}
}
}
if (result_valobj_sp.get() == NULL)
result_valobj_sp = ValueObjectConstResult::Create (NULL, error);
return execution_results;
}