1 files changed, 418 insertions, 0 deletions
diff --git a/contrib/llvm-project/lldb/source/Expression/FunctionCaller.cpp b/contrib/llvm-project/lldb/source/Expression/FunctionCaller.cpp
new file mode 100644
index 000000000000..5ac2b0681ebb
--- /dev/null
+++ b/contrib/llvm-project/lldb/source/Expression/FunctionCaller.cpp
@@ -0,0 +1,418 @@
+//===-- FunctionCaller.cpp ------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+
+#include "lldb/Expression/FunctionCaller.h"
+#include "lldb/Core/Module.h"
+#include "lldb/Core/ValueObject.h"
+#include "lldb/Core/ValueObjectList.h"
+#include "lldb/Expression/DiagnosticManager.h"
+#include "lldb/Expression/IRExecutionUnit.h"
+#include "lldb/Interpreter/CommandReturnObject.h"
+#include "lldb/Symbol/Function.h"
+#include "lldb/Symbol/Type.h"
+#include "lldb/Target/ExecutionContext.h"
+#include "lldb/Target/Process.h"
+#include "lldb/Target/RegisterContext.h"
+#include "lldb/Target/Target.h"
+#include "lldb/Target/Thread.h"
+#include "lldb/Target/ThreadPlan.h"
+#include "lldb/Target/ThreadPlanCallFunction.h"
+#include "lldb/Utility/DataExtractor.h"
+#include "lldb/Utility/LLDBLog.h"
+#include "lldb/Utility/Log.h"
+#include "lldb/Utility/State.h"
+
+using namespace lldb_private;
+
+char FunctionCaller::ID;
+
+// FunctionCaller constructor
+FunctionCaller::FunctionCaller(ExecutionContextScope &exe_scope,
+                               const CompilerType &return_type,
+                               const Address &functionAddress,
+                               const ValueList &arg_value_list,
+                               const char *name)
+    : Expression(exe_scope), m_execution_unit_sp(), m_parser(),
+      m_jit_module_wp(), m_name(name ? name : "<unknown>"),
+      m_function_ptr(nullptr), m_function_addr(functionAddress),
+      m_function_return_type(return_type),
+      m_wrapper_function_name("__lldb_caller_function"),
+      m_wrapper_struct_name("__lldb_caller_struct"), m_wrapper_args_addrs(),
+      m_struct_valid(false), m_struct_size(0), m_return_size(0),
+      m_return_offset(0), m_arg_values(arg_value_list), m_compiled(false),
+      m_JITted(false) {
+  m_jit_process_wp = lldb::ProcessWP(exe_scope.CalculateProcess());
+  // Can't make a FunctionCaller without a process.
+  assert(m_jit_process_wp.lock());
+}
+
+// Destructor
+FunctionCaller::~FunctionCaller() {
+  lldb::ProcessSP process_sp(m_jit_process_wp.lock());
+  if (process_sp) {
+    lldb::ModuleSP jit_module_sp(m_jit_module_wp.lock());
+    if (jit_module_sp)
+      process_sp->GetTarget().GetImages().Remove(jit_module_sp);
+  }
+}
+
+bool FunctionCaller::WriteFunctionWrapper(
+    ExecutionContext &exe_ctx, DiagnosticManager &diagnostic_manager) {
+  Process *process = exe_ctx.GetProcessPtr();
+
+  if (!process) {
+    diagnostic_manager.Printf(lldb::eSeverityError, "no process.");
+    return false;
+  }
+  
+  lldb::ProcessSP jit_process_sp(m_jit_process_wp.lock());
+
+  if (process != jit_process_sp.get()) {
+    diagnostic_manager.Printf(lldb::eSeverityError,
+                              "process does not match the stored process.");
+    return false;
+  }
+    
+  if (process->GetState() != lldb::eStateStopped) {
+    diagnostic_manager.Printf(lldb::eSeverityError, "process is not stopped");
+    return false;
+  }
+
+  if (!m_compiled) {
+    diagnostic_manager.Printf(lldb::eSeverityError, "function not compiled");
+    return false;
+  }
+  
+  if (m_JITted)
+    return true;
+
+  bool can_interpret = false; // should stay that way
+
+  Status jit_error(m_parser->PrepareForExecution(
+      m_jit_start_addr, m_jit_end_addr, m_execution_unit_sp, exe_ctx,
+      can_interpret, eExecutionPolicyAlways));
+
+  if (!jit_error.Success()) {
+    diagnostic_manager.Printf(lldb::eSeverityError,
+                              "Error in PrepareForExecution: %s.",
+                              jit_error.AsCString());
+    return false;
+  }
+
+  if (m_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.SetFilename(const_func_name);
+      jit_module_sp->SetFileSpecAndObjectName(jit_file, ConstString());
+      m_jit_module_wp = jit_module_sp;
+      process->GetTarget().GetImages().Append(jit_module_sp,
+                                              true /* notify */);
+    }
+  }
+  if (process && m_jit_start_addr)
+    m_jit_process_wp = process->shared_from_this();
+
+  m_JITted = true;
+
+  return true;
+}
+
+bool FunctionCaller::WriteFunctionArguments(
+    ExecutionContext &exe_ctx, lldb::addr_t &args_addr_ref,
+    DiagnosticManager &diagnostic_manager) {
+  return WriteFunctionArguments(exe_ctx, args_addr_ref, m_arg_values,
+                                diagnostic_manager);
+}
+
+// FIXME: Assure that the ValueList we were passed in is consistent with the one
+// that defined this function.
+
+bool FunctionCaller::WriteFunctionArguments(
+    ExecutionContext &exe_ctx, lldb::addr_t &args_addr_ref,
+    ValueList &arg_values, DiagnosticManager &diagnostic_manager) {
+  // All the information to reconstruct the struct is provided by the
+  // StructExtractor.
+  if (!m_struct_valid) {
+    diagnostic_manager.PutString(lldb::eSeverityError,
+                                 "Argument information was not correctly "
+                                 "parsed, so the function cannot be called.");
+    return false;
+  }
+
+  Status error;
+  lldb::ExpressionResults return_value = lldb::eExpressionSetupError;
+
+  Process *process = exe_ctx.GetProcessPtr();
+
+  if (process == nullptr)
+    return return_value;
+
+  lldb::ProcessSP jit_process_sp(m_jit_process_wp.lock());
+
+  if (process != jit_process_sp.get())
+    return false;
+
+  if (args_addr_ref == LLDB_INVALID_ADDRESS) {
+    args_addr_ref = process->AllocateMemory(
+        m_struct_size, lldb::ePermissionsReadable | lldb::ePermissionsWritable,
+        error);
+    if (args_addr_ref == LLDB_INVALID_ADDRESS)
+      return false;
+    m_wrapper_args_addrs.push_back(args_addr_ref);
+  } else {
+    // Make sure this is an address that we've already handed out.
+    if (find(m_wrapper_args_addrs.begin(), m_wrapper_args_addrs.end(),
+             args_addr_ref) == m_wrapper_args_addrs.end()) {
+      return false;
+    }
+  }
+
+  // TODO: verify fun_addr needs to be a callable address
+  Scalar fun_addr(
+      m_function_addr.GetCallableLoadAddress(exe_ctx.GetTargetPtr()));
+  uint64_t first_offset = m_member_offsets[0];
+  process->WriteScalarToMemory(args_addr_ref + first_offset, fun_addr,
+                               process->GetAddressByteSize(), error);
+
+  // FIXME: We will need to extend this for Variadic functions.
+
+  Status value_error;
+
+  size_t num_args = arg_values.GetSize();
+  if (num_args != m_arg_values.GetSize()) {
+    diagnostic_manager.Printf(
+        lldb::eSeverityError,
+        "Wrong number of arguments - was: %" PRIu64 " should be: %" PRIu64 "",
+        (uint64_t)num_args, (uint64_t)m_arg_values.GetSize());
+    return false;
+  }
+
+  for (size_t i = 0; i < num_args; i++) {
+    // FIXME: We should sanity check sizes.
+
+    uint64_t offset = m_member_offsets[i + 1]; // Clang sizes are in bytes.
+    Value *arg_value = arg_values.GetValueAtIndex(i);
+
+    // FIXME: For now just do scalars:
+
+    // Special case: if it's a pointer, don't do anything (the ABI supports
+    // passing cstrings)
+
+    if (arg_value->GetValueType() == Value::ValueType::HostAddress &&
+        arg_value->GetContextType() == Value::ContextType::Invalid &&
+        arg_value->GetCompilerType().IsPointerType())
+      continue;
+
+    const Scalar &arg_scalar = arg_value->ResolveValue(&exe_ctx);
+
+    if (!process->WriteScalarToMemory(args_addr_ref + offset, arg_scalar,
+                                      arg_scalar.GetByteSize(), error))
+      return false;
+  }
+
+  return true;
+}
+
+bool FunctionCaller::InsertFunction(ExecutionContext &exe_ctx,
+                                    lldb::addr_t &args_addr_ref,
+                                    DiagnosticManager &diagnostic_manager) {
+  // Since we might need to call allocate memory and maybe call code to make
+  // the caller, we need to be stopped.
+  Process *process = exe_ctx.GetProcessPtr();
+  if (!process) {
+    diagnostic_manager.PutString(lldb::eSeverityError, "no process");
+    return false;
+  }
+  if (process->GetState() != lldb::eStateStopped) {
+    diagnostic_manager.PutString(lldb::eSeverityError, "process running");
+    return false;
+  }
+  if (CompileFunction(exe_ctx.GetThreadSP(), diagnostic_manager) != 0)
+    return false;
+  if (!WriteFunctionWrapper(exe_ctx, diagnostic_manager))
+    return false;
+  if (!WriteFunctionArguments(exe_ctx, args_addr_ref, diagnostic_manager))
+    return false;
+
+  Log *log = GetLog(LLDBLog::Step);
+  LLDB_LOGF(log, "Call Address: 0x%" PRIx64 " Struct Address: 0x%" PRIx64 ".\n",
+            m_jit_start_addr, args_addr_ref);
+
+  return true;
+}
+
+lldb::ThreadPlanSP FunctionCaller::GetThreadPlanToCallFunction(
+    ExecutionContext &exe_ctx, lldb::addr_t args_addr,
+    const EvaluateExpressionOptions &options,
+    DiagnosticManager &diagnostic_manager) {
+  Log *log(GetLog(LLDBLog::Expressions | LLDBLog::Step));
+
+  LLDB_LOGF(log,
+            "-- [FunctionCaller::GetThreadPlanToCallFunction] Creating "
+            "thread plan to call function \"%s\" --",
+            m_name.c_str());
+
+  // FIXME: Use the errors Stream for better error reporting.
+  Thread *thread = exe_ctx.GetThreadPtr();
+  if (thread == nullptr) {
+    diagnostic_manager.PutString(
+        lldb::eSeverityError, "Can't call a function without a valid thread.");
+    return nullptr;
+  }
+
+  // Okay, now run the function:
+
+  Address wrapper_address(m_jit_start_addr);
+
+  lldb::addr_t args = {args_addr};
+
+  lldb::ThreadPlanSP new_plan_sp(new ThreadPlanCallFunction(
+      *thread, wrapper_address, CompilerType(), args, options));
+  new_plan_sp->SetIsControllingPlan(true);
+  new_plan_sp->SetOkayToDiscard(false);
+  return new_plan_sp;
+}
+
+bool FunctionCaller::FetchFunctionResults(ExecutionContext &exe_ctx,
+                                          lldb::addr_t args_addr,
+                                          Value &ret_value) {
+  // Read the return value - it is the last field in the struct:
+  // FIXME: How does clang tell us there's no return value?  We need to handle
+  // that case.
+  // FIXME: Create our ThreadPlanCallFunction with the return CompilerType, and
+  // then use GetReturnValueObject
+  // to fetch the value.  That way we can fetch any values we need.
+
+  Log *log(GetLog(LLDBLog::Expressions | LLDBLog::Step));
+
+  LLDB_LOGF(log,
+            "-- [FunctionCaller::FetchFunctionResults] Fetching function "
+            "results for \"%s\"--",
+            m_name.c_str());
+
+  Process *process = exe_ctx.GetProcessPtr();
+
+  if (process == nullptr)
+    return false;
+
+  lldb::ProcessSP jit_process_sp(m_jit_process_wp.lock());
+
+  if (process != jit_process_sp.get())
+    return false;
+
+  Status error;
+  ret_value.GetScalar() = process->ReadUnsignedIntegerFromMemory(
+      args_addr + m_return_offset, m_return_size, 0, error);
+
+  if (error.Fail())
+    return false;
+
+  ret_value.SetCompilerType(m_function_return_type);
+  ret_value.SetValueType(Value::ValueType::Scalar);
+  return true;
+}
+
+void FunctionCaller::DeallocateFunctionResults(ExecutionContext &exe_ctx,
+                                               lldb::addr_t args_addr) {
+  std::list<lldb::addr_t>::iterator pos;
+  pos = std::find(m_wrapper_args_addrs.begin(), m_wrapper_args_addrs.end(),
+                  args_addr);
+  if (pos != m_wrapper_args_addrs.end())
+    m_wrapper_args_addrs.erase(pos);
+
+  exe_ctx.GetProcessRef().DeallocateMemory(args_addr);
+}
+
+lldb::ExpressionResults FunctionCaller::ExecuteFunction(
+    ExecutionContext &exe_ctx, lldb::addr_t *args_addr_ptr,
+    const EvaluateExpressionOptions &options,
+    DiagnosticManager &diagnostic_manager, Value &results) {
+  lldb::ExpressionResults return_value = lldb::eExpressionSetupError;
+
+  // FunctionCaller::ExecuteFunction execution is always just to get the
+  // result. Unless explicitly asked for, ignore breakpoints and unwind on
+  // error.
+  const bool enable_debugging =
+      exe_ctx.GetTargetPtr() &&
+      exe_ctx.GetTargetPtr()->GetDebugUtilityExpression();
+  EvaluateExpressionOptions real_options = options;
+  real_options.SetDebug(false); // This halts the expression for debugging.
+  real_options.SetGenerateDebugInfo(enable_debugging);
+  real_options.SetUnwindOnError(!enable_debugging);
+  real_options.SetIgnoreBreakpoints(!enable_debugging);
+
+  lldb::addr_t args_addr;
+
+  if (args_addr_ptr != nullptr)
+    args_addr = *args_addr_ptr;
+  else
+    args_addr = LLDB_INVALID_ADDRESS;
+
+  if (CompileFunction(exe_ctx.GetThreadSP(), diagnostic_manager) != 0)
+    return lldb::eExpressionSetupError;
+
+  if (args_addr == LLDB_INVALID_ADDRESS) {
+    if (!InsertFunction(exe_ctx, args_addr, diagnostic_manager))
+      return lldb::eExpressionSetupError;
+  }
+
+  Log *log(GetLog(LLDBLog::Expressions | LLDBLog::Step));
+
+  LLDB_LOGF(log,
+            "== [FunctionCaller::ExecuteFunction] Executing function \"%s\" ==",
+            m_name.c_str());
+
+  lldb::ThreadPlanSP call_plan_sp = GetThreadPlanToCallFunction(
+      exe_ctx, args_addr, real_options, diagnostic_manager);
+  if (!call_plan_sp)
+    return lldb::eExpressionSetupError;
+
+  // We need to make sure we record the fact that we are running an expression
+  // here otherwise this fact will fail to be recorded when fetching an
+  // Objective-C object description
+  if (exe_ctx.GetProcessPtr())
+    exe_ctx.GetProcessPtr()->SetRunningUserExpression(true);
+
+  return_value = exe_ctx.GetProcessRef().RunThreadPlan(
+      exe_ctx, call_plan_sp, real_options, diagnostic_manager);
+
+  if (log) {
+    if (return_value != lldb::eExpressionCompleted) {
+      LLDB_LOGF(log,
+                "== [FunctionCaller::ExecuteFunction] Execution of \"%s\" "
+                "completed abnormally: %s ==",
+                m_name.c_str(),
+                Process::ExecutionResultAsCString(return_value));
+    } else {
+      LLDB_LOGF(log,
+                "== [FunctionCaller::ExecuteFunction] Execution of \"%s\" "
+                "completed normally ==",
+                m_name.c_str());
+    }
+  }
+
+  if (exe_ctx.GetProcessPtr())
+    exe_ctx.GetProcessPtr()->SetRunningUserExpression(false);
+
+  if (args_addr_ptr != nullptr)
+    *args_addr_ptr = args_addr;
+
+  if (return_value != lldb::eExpressionCompleted)
+    return return_value;
+
+  FetchFunctionResults(exe_ctx, args_addr, results);
+
+  if (args_addr_ptr == nullptr)
+    DeallocateFunctionResults(exe_ctx, args_addr);
+
+  return lldb::eExpressionCompleted;
+}