teak-llvm/lldb/source/Commands/CommandObjectExpression.cpp
Sean Callanan 1a8d40935d This is a major refactoring of the expression parser.
The goal is to separate the parser's data from the data
belonging to the parser's clients.  This allows clients
to use the parser to obtain (for example) a JIT compiled
function or some DWARF code, and then discard the parser
state.

Previously, parser state was held in ClangExpression and
used liberally by ClangFunction, which inherited from
ClangExpression.  The main effects of this refactoring 
are:

- reducing ClangExpression to an abstract class that
  declares methods that any client must expose to the
  expression parser,

- moving the code specific to implementing the "expr"
  command from ClangExpression and
  CommandObjectExpression into ClangUserExpression,
  a new class,

- moving the common parser interaction code from
  ClangExpression into ClangExpressionParser, a new
  class, and

- making ClangFunction rely only on
  ClangExpressionParser and not depend on the
  internal implementation of ClangExpression.

Side effects include:

- the compiler interaction code has been factored
  out of ClangFunction and is now in an AST pass
  (ASTStructExtractor),

- the header file for ClangFunction is now fully
  documented,

- several bugs that only popped up when Clang was
  deallocated (which never happened, since the
  lifetime of the compiler was essentially infinite)
  are now fixed, and

- the developer-only "call" command has been
  disabled.

I have tested the expr command and the Objective-C
step-into code, which use ClangUserExpression and
ClangFunction, respectively, and verified that they
work.  Please let me know if you encounter bugs or
poor documentation.

llvm-svn: 112249
2010-08-27 01:01:44 +00:00

336 lines
9.7 KiB
C++

//===-- CommandObjectExpression.cpp -----------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "CommandObjectExpression.h"
// C Includes
// C++ Includes
// Other libraries and framework includes
// Project includes
#include "lldb/Interpreter/Args.h"
#include "lldb/Core/Value.h"
#include "lldb/Core/InputReader.h"
#include "lldb/Expression/ClangExpressionVariable.h"
#include "lldb/Expression/ClangUserExpression.h"
#include "lldb/Expression/ClangFunction.h"
#include "lldb/Expression/DWARFExpression.h"
#include "lldb/Host/Host.h"
#include "lldb/Core/Debugger.h"
#include "lldb/Interpreter/CommandInterpreter.h"
#include "lldb/Interpreter/CommandReturnObject.h"
#include "lldb/Symbol/ObjectFile.h"
#include "lldb/Symbol/Variable.h"
#include "lldb/Target/Process.h"
#include "lldb/Target/StackFrame.h"
#include "lldb/Target/Target.h"
#include "llvm/ADT/StringRef.h"
using namespace lldb;
using namespace lldb_private;
CommandObjectExpression::CommandOptions::CommandOptions () :
Options()
{
// Keep only one place to reset the values to their defaults
ResetOptionValues();
}
CommandObjectExpression::CommandOptions::~CommandOptions ()
{
}
Error
CommandObjectExpression::CommandOptions::SetOptionValue (int option_idx, const char *option_arg)
{
Error error;
char short_option = (char) m_getopt_table[option_idx].val;
switch (short_option)
{
case 'l':
if (language.SetLanguageFromCString (option_arg) == false)
{
error.SetErrorStringWithFormat("Invalid language option argument '%s'.\n", option_arg);
}
break;
case 'g':
debug = true;
break;
case 'f':
error = Args::StringToFormat(option_arg, format);
break;
default:
error.SetErrorStringWithFormat("Invalid short option character '%c'.\n", short_option);
break;
}
return error;
}
void
CommandObjectExpression::CommandOptions::ResetOptionValues ()
{
Options::ResetOptionValues();
language.Clear();
debug = false;
format = eFormatDefault;
show_types = true;
show_summary = true;
}
const lldb::OptionDefinition*
CommandObjectExpression::CommandOptions::GetDefinitions ()
{
return g_option_table;
}
CommandObjectExpression::CommandObjectExpression () :
CommandObject (
"expression",
"Evaluate a C expression in the current program context, using variables currently in scope.",
"expression [<cmd-options>] <expr>"),
m_expr_line_count (0),
m_expr_lines ()
{
SetHelpLong(
"Examples: \n\
\n\
expr my_struct->a = my_array[3] \n\
expr -f bin -- (index * 8) + 5 \n\
expr char c[] = \"foo\"; c[0]\n");
}
CommandObjectExpression::~CommandObjectExpression ()
{
}
Options *
CommandObjectExpression::GetOptions ()
{
return &m_options;
}
bool
CommandObjectExpression::Execute
(
CommandInterpreter &interpreter,
Args& command,
CommandReturnObject &result
)
{
return false;
}
size_t
CommandObjectExpression::MultiLineExpressionCallback
(
void *baton,
InputReader &reader,
lldb::InputReaderAction notification,
const char *bytes,
size_t bytes_len
)
{
CommandObjectExpression *cmd_object_expr = (CommandObjectExpression *) baton;
switch (notification)
{
case eInputReaderActivate:
reader.GetDebugger().GetOutputStream().Printf("%s\n", "Enter expressions, then terminate with an empty line to evaluate:");
// Fall through
case eInputReaderReactivate:
//if (out_fh)
// reader.GetDebugger().GetOutputStream().Printf ("%3u: ", cmd_object_expr->m_expr_line_count);
break;
case eInputReaderDeactivate:
break;
case eInputReaderGotToken:
++cmd_object_expr->m_expr_line_count;
if (bytes && bytes_len)
{
cmd_object_expr->m_expr_lines.append (bytes, bytes_len + 1);
}
if (bytes_len == 0)
reader.SetIsDone(true);
//else if (out_fh && !reader->IsDone())
// ::fprintf (out_fh, "%3u: ", cmd_object_expr->m_expr_line_count);
break;
case eInputReaderDone:
{
bool bare = false;
cmd_object_expr->EvaluateExpression (cmd_object_expr->m_expr_lines.c_str(),
bare,
reader.GetDebugger().GetOutputStream(),
reader.GetDebugger().GetErrorStream());
}
break;
}
return bytes_len;
}
bool
CommandObjectExpression::EvaluateExpression (const char *expr, bool bare, Stream &output_stream, Stream &error_stream,
CommandReturnObject *result)
{
ClangUserExpression user_expression (expr);
if (!user_expression.Parse (error_stream, m_exe_ctx))
{
error_stream.Printf ("Couldn't parse the expresssion");
return false;
}
ClangExpressionVariable *expr_result;
if (!user_expression.Execute (error_stream, m_exe_ctx, expr_result))
{
error_stream.Printf ("Couldn't execute the expresssion");
return false;
}
if (expr_result)
{
StreamString ss;
Error rc = expr_result->Print (ss,
m_exe_ctx,
m_options.format,
m_options.show_types,
m_options.show_summary,
m_options.debug);
if (rc.Fail()) {
error_stream.Printf ("Couldn't print result : %s\n", rc.AsCString());
return false;
}
output_stream.PutCString(ss.GetString().c_str());
if (result)
result->SetStatus (eReturnStatusSuccessFinishResult);
}
else
{
error_stream.Printf ("Expression produced no result\n");
if (result)
result->SetStatus (eReturnStatusSuccessFinishNoResult);
}
return true;
}
bool
CommandObjectExpression::ExecuteRawCommandString
(
CommandInterpreter &interpreter,
const char *command,
CommandReturnObject &result
)
{
m_exe_ctx = interpreter.GetDebugger().GetExecutionContext();
m_options.ResetOptionValues();
const char * expr = NULL;
if (command[0] == '\0')
{
m_expr_lines.clear();
m_expr_line_count = 0;
InputReaderSP reader_sp (new InputReader(interpreter.GetDebugger()));
if (reader_sp)
{
Error err (reader_sp->Initialize (CommandObjectExpression::MultiLineExpressionCallback,
this, // baton
eInputReaderGranularityLine, // token size, to pass to callback function
NULL, // end token
NULL, // prompt
true)); // echo input
if (err.Success())
{
interpreter.GetDebugger().PushInputReader (reader_sp);
result.SetStatus (eReturnStatusSuccessFinishNoResult);
}
else
{
result.AppendError (err.AsCString());
result.SetStatus (eReturnStatusFailed);
}
}
else
{
result.AppendError("out of memory");
result.SetStatus (eReturnStatusFailed);
}
return result.Succeeded();
}
if (command[0] == '-')
{
// We have some options and these options MUST end with --.
const char *end_options = NULL;
const char *s = command;
while (s && s[0])
{
end_options = ::strstr (s, "--");
if (end_options)
{
end_options += 2; // Get past the "--"
if (::isspace (end_options[0]))
{
expr = end_options;
while (::isspace (*expr))
++expr;
break;
}
}
s = end_options;
}
if (end_options)
{
Args args (command, end_options - command);
if (!ParseOptions (interpreter, args, result))
return false;
}
}
if (expr == NULL)
expr = command;
if (EvaluateExpression (expr, false, result.GetOutputStream(), result.GetErrorStream(), &result))
return true;
result.SetStatus (eReturnStatusFailed);
return false;
}
lldb::OptionDefinition
CommandObjectExpression::CommandOptions::g_option_table[] =
{
{ LLDB_OPT_SET_ALL, false, "language", 'l', required_argument, NULL, 0, "[c|c++|objc|objc++]", "Sets the language to use when parsing the expression."},
{ LLDB_OPT_SET_ALL, false, "format", 'f', required_argument, NULL, 0, "[ [bool|b] | [bin] | [char|c] | [oct|o] | [dec|i|d|u] | [hex|x] | [float|f] | [cstr|s] ]", "Specify the format that the expression output should use."},
{ LLDB_OPT_SET_ALL, false, "debug", 'g', no_argument, NULL, 0, NULL, "Enable verbose debug logging of the expression parsing and evaluation."},
{ LLDB_OPT_SET_ALL, false, "use-ir", 'i', no_argument, NULL, 0, NULL, "[Temporary] Instructs the expression evaluator to use IR instead of ASTs."},
{ 0, false, NULL, 0, 0, NULL, NULL, NULL, NULL }
};