Files
llvm/lldb/source/Expression/ClangUtilityFunction.cpp
Jim Ingham 151c032c86 This patch makes Clang-independent base classes for all the expression types that lldb currently vends.
Before we had:

ClangFunction
ClangUtilityFunction
ClangUserExpression

and code all over in lldb that explicitly made Clang-based expressions. This patch adds an Expression 
base class, and three pure virtual implementations for the Expression kinds:

FunctionCaller
UtilityFunction
UserExpression

You can request one of these expression types from the Target using the Get<ExpressionType>ForLanguage. 
The Target will then consult all the registered TypeSystem plugins, and if the type system that matches 
the language can make an expression of that kind, it will do so and return it.

Because all of the real expression types need to communicate with their ExpressionParser in a uniform way, 
I also added a ExpressionTypeSystemHelper class that expressions generically can vend, and a ClangExpressionHelper 
that encapsulates the operations that the ClangExpressionParser needs to perform on the ClangExpression types. 
Then each of the Clang* expression kinds constructs the appropriate helper to do what it needs.

The patch also fixes a wart in the UtilityFunction that to use it you had to create a parallel FunctionCaller 
to actually call the function made by the UtilityFunction. Now the UtilityFunction can be asked to vend a 
FunctionCaller that will run its function. This cleaned up a lot of boiler plate code using UtilityFunctions.

Note, in this patch all the expression types explicitly depend on the LLVM JIT and IR, and all the common 
JIT running code is in the FunctionCaller etc base classes. At some point we could also abstract that dependency 
but I don't see us adding another back end in the near term, so I'll leave that exercise till it is actually necessary.

llvm-svn: 247720
2015-09-15 21:13:50 +00:00

189 lines
5.5 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 "lldb/Core/ConstString.h"
#include "lldb/Core/Log.h"
#include "lldb/Core/Module.h"
#include "lldb/Core/Stream.h"
#include "lldb/Core/StreamFile.h"
#include "lldb/Expression/ClangExpressionDeclMap.h"
#include "lldb/Expression/ClangExpressionParser.h"
#include "lldb/Expression/ClangUtilityFunction.h"
#include "lldb/Expression/ExpressionSourceCode.h"
#include "lldb/Expression/IRExecutionUnit.h"
#include "lldb/Host/Host.h"
#include "lldb/Target/ExecutionContext.h"
#include "lldb/Target/Target.h"
using namespace lldb_private;
//------------------------------------------------------------------
/// Constructor
///
/// @param[in] text
/// The text of the function. Must be a full translation unit.
///
/// @param[in] name
/// The name of the function, as used in the text.
//------------------------------------------------------------------
ClangUtilityFunction::ClangUtilityFunction (ExecutionContextScope &exe_scope,
const char *text,
const char *name) :
UtilityFunction (exe_scope, text, name)
{
}
ClangUtilityFunction::~ClangUtilityFunction ()
{
}
//------------------------------------------------------------------
/// Install the utility function into a process
///
/// @param[in] error_stream
/// A stream to print parse errors and warnings to.
///
/// @param[in] exe_ctx
/// The execution context to install the utility function to.
///
/// @return
/// True on success (no errors); false otherwise.
//------------------------------------------------------------------
bool
ClangUtilityFunction::Install (Stream &error_stream,
ExecutionContext &exe_ctx)
{
if (m_jit_start_addr != LLDB_INVALID_ADDRESS)
{
error_stream.PutCString("error: already installed\n");
return false;
}
////////////////////////////////////
// Set up the target and compiler
//
Target *target = exe_ctx.GetTargetPtr();
if (!target)
{
error_stream.PutCString ("error: invalid target\n");
return false;
}
Process *process = exe_ctx.GetProcessPtr();
if (!process)
{
error_stream.PutCString ("error: invalid process\n");
return false;
}
//////////////////////////
// Parse the expression
//
bool keep_result_in_memory = false;
ResetDeclMap(exe_ctx, keep_result_in_memory);
if (!DeclMap()->WillParse(exe_ctx, NULL))
{
error_stream.PutCString ("error: current process state is unsuitable for expression parsing\n");
return false;
}
const bool generate_debug_info = true;
ClangExpressionParser parser(exe_ctx.GetBestExecutionContextScope(), *this, generate_debug_info);
unsigned num_errors = parser.Parse (error_stream);
if (num_errors)
{
error_stream.Printf ("error: %d errors parsing expression\n", num_errors);
ResetDeclMap();
return false;
}
//////////////////////////////////
// JIT the output of the parser
//
bool can_interpret = false; // should stay that way
Error jit_error = parser.PrepareForExecution (m_jit_start_addr,
m_jit_end_addr,
m_execution_unit_sp,
exe_ctx,
can_interpret,
eExecutionPolicyAlways);
if (m_jit_start_addr != LLDB_INVALID_ADDRESS)
{
m_jit_process_wp = process->shared_from_this();
if (parser.GetGenerateDebugInfo())
{
lldb::ModuleSP jit_module_sp ( m_execution_unit_sp->GetJITModule());
if (jit_module_sp)
{
ConstString const_func_name(FunctionName());
FileSpec jit_file;
jit_file.GetFilename() = const_func_name;
jit_module_sp->SetFileSpecAndObjectName (jit_file, ConstString());
m_jit_module_wp = jit_module_sp;
target->GetImages().Append(jit_module_sp);
}
}
}
#if 0
// jingham: look here
StreamFile logfile ("/tmp/exprs.txt", "a");
logfile.Printf ("0x%16.16" PRIx64 ": func = %s, source =\n%s\n",
m_jit_start_addr,
m_function_name.c_str(),
m_function_text.c_str());
#endif
DeclMap()->DidParse();
ResetDeclMap();
if (jit_error.Success())
{
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");
return false;
}
}
void
ClangUtilityFunction::ClangUtilityFunctionHelper::ResetDeclMap(ExecutionContext &exe_ctx, bool keep_result_in_memory)
{
m_expr_decl_map_up.reset(new ClangExpressionDeclMap(keep_result_in_memory, exe_ctx));
}