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@@ -0,0 +1,703 @@
+/*
+
+Copyright (C) 2009-2012 John W. Eaton
+
+This file is part of Octave.
+
+Octave is free software; you can redistribute it and/or modify it
+under the terms of the GNU General Public License as published by the
+Free Software Foundation; either version 3 of the License, or (at your
+option) any later version.
+
+Octave is distributed in the hope that it will be useful, but WITHOUT
+ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+for more details.
+
+You should have received a copy of the GNU General Public License
+along with Octave; see the file COPYING.  If not, see
+<http://www.gnu.org/licenses/>.
+
+*/
+
+#define __STDC_LIMIT_MACROS
+#define __STDC_CONSTANT_MACROS
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include "pt-jit.h"
+
+#include <typeinfo>
+
+#include <llvm/LLVMContext.h>
+#include <llvm/Module.h>
+#include <llvm/Function.h>
+#include <llvm/BasicBlock.h>
+#include <llvm/Support/IRBuilder.h>
+#include <llvm/ExecutionEngine/ExecutionEngine.h>
+#include <llvm/ExecutionEngine/JIT.h>
+#include <llvm/PassManager.h>
+#include <llvm/Analysis/Verifier.h>
+#include <llvm/Analysis/Passes.h>
+#include <llvm/Target/TargetData.h>
+#include <llvm/Transforms/Scalar.h>
+#include <llvm/Support/TargetSelect.h>
+#include <llvm/Support/raw_os_ostream.h>
+
+#include "ov-fcn-handle.h"
+#include "ov-usr-fcn.h"
+#include "pt-all.h"
+
+using namespace llvm;
+
+//FIXME: Move into tree_jit
+static IRBuilder<> builder (getGlobalContext ());
+
+extern "C" void
+octave_print_double (const char *name, double value)
+{
+  // FIXME: We should avoid allocating a new octave_scalar each time
+  octave_value ov (value);
+  ov.print_with_name (octave_stdout, name);
+}
+
+tree_jit::tree_jit (void) : context (getGlobalContext ()), engine (0)
+{
+  InitializeNativeTarget ();
+  InitializeNativeTargetAsmPrinter ();
+  module = new Module ("octave", context);
+}
+
+tree_jit::~tree_jit (void)
+{
+  delete module;
+}
+
+bool
+tree_jit::execute (tree& tee)
+{
+  if (!engine)
+    {
+      engine = ExecutionEngine::createJIT (module);
+
+      // initialize pass manager
+      pass_manager = new FunctionPassManager (module);
+      pass_manager->add (new TargetData(*engine->getTargetData ()));
+      pass_manager->add (createBasicAliasAnalysisPass ());
+      pass_manager->add (createPromoteMemoryToRegisterPass ());
+      pass_manager->add (createInstructionCombiningPass ());
+      pass_manager->add (createReassociatePass ());
+      pass_manager->add (createGVNPass ());
+      pass_manager->add (createCFGSimplificationPass ());
+      pass_manager->doInitialization ();
+
+      // create external functions
+      Type *vtype = Type::getVoidTy (context);
+      std::vector<Type*> pd_args (2);
+      pd_args[0] = Type::getInt8PtrTy (context);
+      pd_args[1] = Type::getDoubleTy (context);
+      FunctionType *print_double_ty = FunctionType::get (vtype, pd_args, false);
+      print_double = Function::Create (print_double_ty,
+                                       Function::ExternalLinkage,
+                                       "octave_print_double", module);
+      engine->addGlobalMapping (print_double,
+                                reinterpret_cast<void*>(&octave_print_double));
+    }
+
+  if (!engine)
+    // sometimes this fails during early initialization
+    return false;
+
+  // find function
+  function_info *finfo;
+  finfo_map_iterator iter = compiled_functions.find (&tee);
+
+  if (iter == compiled_functions.end ())
+    finfo = compile (tee);
+  else
+    finfo = iter->second;
+
+  return finfo->execute ();
+}
+
+tree_jit::function_info*
+tree_jit::compile (tree& tee)
+{
+  value_stack.clear ();
+  variables.clear ();
+  
+  // setup function
+  std::vector<Type*> args (2);
+  args[0] = Type::getInt1PtrTy (context);
+  args[1] = Type::getDoublePtrTy (context);
+  FunctionType *ft = FunctionType::get (Type::getVoidTy (context), args, false);
+  Function *compiling = Function::Create (ft, Function::ExternalLinkage,
+                                          "test_fn", module);
+
+  entry_block = BasicBlock::Create (context, "entry", compiling);
+  BasicBlock *body = BasicBlock::Create (context, "body",
+                                         compiling);
+  builder.SetInsertPoint (body);
+
+  // convert tree to LLVM IR
+  try
+    {
+      tee.accept (*this);
+    }
+  catch (const jit_fail_exception&)
+    {
+      //FIXME: cleanup
+      return  compiled_functions[&tee] = new function_info ();
+    }
+
+  // copy input arguments
+  builder.SetInsertPoint (entry_block);
+
+  Function::arg_iterator arg_iter = compiling->arg_begin ();
+  Value *arg_defined = arg_iter;
+  Value *arg_value = ++arg_iter;
+
+  arg_defined->setName ("arg_defined");
+  arg_value->setName ("arg_value");
+
+  size_t idx = 0;
+  std::vector<std::string> arg_names;
+  std::vector<bool> arg_used;
+  for (var_map_iterator iter = variables.begin (); iter != variables.end ();
+       ++iter, ++idx)
+    {
+      arg_names.push_back (iter->first);
+      arg_used.push_back (iter->second.use);
+
+      Value *gep_defined = builder.CreateConstInBoundsGEP1_32 (arg_defined, idx);
+      Value *defined = builder.CreateLoad (gep_defined);
+      builder.CreateStore (defined, iter->second.defined);
+
+      Value *gep_value = builder.CreateConstInBoundsGEP1_32 (arg_value, idx);
+      Value *value = builder.CreateLoad (gep_value);
+      builder.CreateStore (value, iter->second.value);
+    }
+  builder.CreateBr (body);
+
+  // copy output arguments
+  BasicBlock *cleanup = BasicBlock::Create (context, "cleanup", compiling);
+  builder.SetInsertPoint (body);
+  builder.CreateBr (cleanup);
+  builder.SetInsertPoint (cleanup);
+
+  idx = 0;
+  for (var_map_iterator iter = variables.begin (); iter != variables.end ();
+       ++iter, ++idx)
+    {
+      Value *gep_defined = builder.CreateConstInBoundsGEP1_32 (arg_defined, idx);
+      Value *defined = builder.CreateLoad (iter->second.defined);
+      builder.CreateStore (defined, gep_defined);
+
+      Value *gep_value = builder.CreateConstInBoundsGEP1_32 (arg_value, idx);
+      Value *value = builder.CreateLoad (iter->second.value, iter->first);
+      builder.CreateStore (value, gep_value);
+    }
+
+  builder.CreateRetVoid ();
+
+  // print what we compiled (for debugging)
+  // we leave this in for now, as other people might want to view the ir created
+  // should be removed eventually though
+  const bool debug_print_ir = false;
+  if (debug_print_ir)
+    {
+      raw_os_ostream os (std::cout);
+      std::cout << "Compiling --------------------\n";
+      tree_print_code tpc (std::cout);
+      std::cout << typeid (tee).name () << std::endl;
+      tee.accept (tpc);
+      std::cout << "\n--------------------\n";
+
+      std::cout << "llvm_ir\n";
+      compiling->print (os);
+      std::cout << "--------------------\n";
+    }
+  
+  // compile code
+  verifyFunction (*compiling);
+  pass_manager->run (*compiling);
+
+  if (debug_print_ir)
+    {
+      raw_os_ostream os (std::cout);
+      std::cout << "optimized llvm_ir\n";
+      compiling->print (os);
+      std::cout << "--------------------\n";
+    }
+
+  jit_function fun =
+    reinterpret_cast<jit_function> (engine->getPointerToFunction (compiling));
+
+  return compiled_functions[&tee] = new function_info (fun, arg_names, arg_used);
+}
+
+tree_jit::variable_info
+tree_jit::find (const std::string &name, bool use)
+{
+  var_map_iterator iter = variables.find (name);
+  if (iter == variables.end ())
+    {
+      // we currently just assume everything is a double
+      Type *dbl = Type::getDoubleTy (context);
+      Type *bol = Type::getInt1Ty (context);
+      IRBuilder<> tmpB (entry_block, entry_block->begin ());
+
+      variable_info vinfo;
+      vinfo.defined = tmpB.CreateAlloca (bol, 0);
+      vinfo.value = tmpB.CreateAlloca (dbl, 0, name);
+      vinfo.use = use;
+      variables[name] = vinfo;
+      return vinfo;
+    }
+  else
+    {
+      iter->second.use = iter->second.use || use;
+      return iter->second;
+    }
+}
+
+void
+tree_jit::do_assign (variable_info vinfo, llvm::Value *value)
+{
+  // create assign expression
+  Value *result = builder.CreateStore (value, vinfo.value);
+  value_stack.push_back (result);
+
+  // update defined for lhs
+  Type *btype = Type::getInt1Ty (context);
+  Value *btrue = ConstantInt::get (btype, APInt (1, 1));
+  builder.CreateStore (btrue, vinfo.defined);
+}
+
+void
+tree_jit::emit_print (const std::string& vname, llvm::Value *value)
+{
+  Value *pname = builder.CreateGlobalStringPtr (vname);
+  builder.CreateCall2 (print_double, pname, value);
+}
+
+void
+tree_jit::visit_anon_fcn_handle (tree_anon_fcn_handle&)
+{
+  fail ();
+}
+
+void
+tree_jit::visit_argument_list (tree_argument_list&)
+{
+  fail ();
+}
+
+void
+tree_jit::visit_binary_expression (tree_binary_expression& be)
+{
+  tree_expression *lhs = be.lhs ();
+  tree_expression *rhs = be.rhs ();
+  if (lhs && rhs)
+    {
+      lhs->accept (*this);
+      rhs->accept (*this);
+
+      Value *lhsv = value_stack.back ();
+      value_stack.pop_back ();
+
+      Value *rhsv = value_stack.back ();
+      value_stack.pop_back ();
+
+      Value *result;
+      switch (be.op_type ())
+        {
+        case octave_value::op_add:
+          result = builder.CreateFAdd (lhsv, rhsv);
+          break;
+        case octave_value::op_sub:
+          result = builder.CreateFSub (lhsv, rhsv);
+          break;
+        case octave_value::op_mul:
+          result = builder.CreateFMul (lhsv, rhsv);
+          break;
+        case octave_value::op_div:
+          result = builder.CreateFDiv (lhsv, rhsv);
+          break;
+        default:
+          fail ();
+        }
+
+      value_stack.push_back (result);
+    }
+  else
+    fail ();
+}
+
+void
+tree_jit::visit_break_command (tree_break_command&)
+{
+  fail ();
+}
+
+void
+tree_jit::visit_colon_expression (tree_colon_expression&)
+{
+  fail ();
+}
+
+void
+tree_jit::visit_continue_command (tree_continue_command&)
+{
+  fail ();
+}
+
+void
+tree_jit::visit_global_command (tree_global_command&)
+{
+  fail ();
+}
+
+void
+tree_jit::visit_persistent_command (tree_persistent_command&)
+{
+  fail ();
+}
+
+void
+tree_jit::visit_decl_elt (tree_decl_elt&)
+{
+  fail ();
+}
+
+void
+tree_jit::visit_decl_init_list (tree_decl_init_list&)
+{
+  fail ();
+}
+
+void
+tree_jit::visit_simple_for_command (tree_simple_for_command&)
+{
+  fail ();
+}
+
+void
+tree_jit::visit_complex_for_command (tree_complex_for_command&)
+{
+  fail ();
+}
+
+void
+tree_jit::visit_octave_user_script (octave_user_script&)
+{
+  fail ();
+}
+
+void
+tree_jit::visit_octave_user_function (octave_user_function&)
+{
+  fail ();
+}
+
+void
+tree_jit::visit_octave_user_function_header (octave_user_function&)
+{
+  fail ();
+}
+
+void
+tree_jit::visit_octave_user_function_trailer (octave_user_function&)
+{
+  fail ();
+}
+
+void
+tree_jit::visit_function_def (tree_function_def&)
+{
+  fail ();
+}
+
+void
+tree_jit::visit_identifier (tree_identifier& ti)
+{
+  octave_value ov = ti.do_lookup ();
+  if (ov.is_function ())
+    fail ();
+
+  std::string name = ti.name ();
+  variable_info vinfo = find (ti.name (), true);
+
+  // TODO check defined
+
+  Value *load_value = builder.CreateLoad (vinfo.value, name);
+  value_stack.push_back (load_value);
+}
+
+void
+tree_jit::visit_if_clause (tree_if_clause&)
+{
+  fail ();
+}
+
+void
+tree_jit::visit_if_command (tree_if_command&)
+{
+  fail ();
+}
+
+void
+tree_jit::visit_if_command_list (tree_if_command_list&)
+{
+  fail ();
+}
+
+void
+tree_jit::visit_index_expression (tree_index_expression&)
+{
+  fail ();
+}
+
+void
+tree_jit::visit_matrix (tree_matrix&)
+{
+  fail ();
+}
+
+void
+tree_jit::visit_cell (tree_cell&)
+{
+  fail ();
+}
+
+void
+tree_jit::visit_multi_assignment (tree_multi_assignment&)
+{
+  fail ();
+}
+
+void
+tree_jit::visit_no_op_command (tree_no_op_command&)
+{
+  fail ();
+}
+
+void
+tree_jit::visit_constant (tree_constant& tc)
+{
+  octave_value v = tc.rvalue1 ();
+  if (v.is_real_scalar () && v.is_double_type ())
+    {
+      double dv = v.double_value ();
+      Value *lv = ConstantFP::get (context,  APFloat (dv));
+      value_stack.push_back (lv);
+    }
+  else
+    fail ();
+}
+
+void
+tree_jit::visit_fcn_handle (tree_fcn_handle&)
+{
+  fail ();
+}
+
+void
+tree_jit::visit_parameter_list (tree_parameter_list&)
+{
+  fail ();
+}
+
+void
+tree_jit::visit_postfix_expression (tree_postfix_expression&)
+{
+  fail ();
+}
+
+void
+tree_jit::visit_prefix_expression (tree_prefix_expression&)
+{
+  fail ();
+}
+
+void
+tree_jit::visit_return_command (tree_return_command&)
+{
+  fail ();
+}
+
+void
+tree_jit::visit_return_list (tree_return_list&)
+{
+  fail ();
+}
+
+void
+tree_jit::visit_simple_assignment (tree_simple_assignment& tsa)
+{
+  // only support an identifier as lhs
+  tree_identifier *lhs = dynamic_cast<tree_identifier*> (tsa.left_hand_side ());
+  if (!lhs)
+    fail ();
+
+  variable_info lhsv = find (lhs->name (), false);
+  
+  // resolve rhs as normal
+  tree_expression *rhs = tsa.right_hand_side ();
+  rhs->accept (*this);
+
+  Value *rhsv = value_stack.back ();
+  value_stack.pop_back ();
+
+  do_assign (lhsv, rhsv);
+
+  if (tsa.print_result ())
+    emit_print (lhs->name (), rhsv);
+}
+
+void
+tree_jit::visit_statement (tree_statement& stmt)
+{
+  tree_command *cmd = stmt.command ();
+  tree_expression *expr = stmt.expression ();
+
+  if (cmd)
+    cmd->accept (*this);
+  else
+    {
+      // TODO deal with printing
+
+      // stolen from tree_evaluator::visit_statement
+      bool do_bind_ans = false;
+
+      if (expr->is_identifier ())
+        {
+          tree_identifier *id = dynamic_cast<tree_identifier *> (expr);
+
+          do_bind_ans = (! id->is_variable ());
+        }
+      else
+        do_bind_ans = (! expr->is_assignment_expression ());
+
+      expr->accept (*this);
+
+      if (do_bind_ans)
+        {
+          Value *rhs = value_stack.back ();
+          value_stack.pop_back ();
+
+          variable_info ans = find ("ans", false);
+          do_assign (ans, rhs);
+        }
+      else if (expr->is_identifier () && expr->print_result ())
+        {
+          // FIXME: ugly hack, we need to come up with a way to pass
+          // nargout to visit_identifier
+          emit_print (expr->name (), value_stack.back ());
+        }
+
+
+      value_stack.pop_back ();
+    }
+}
+
+void
+tree_jit::visit_statement_list (tree_statement_list&)
+{
+  fail ();
+}
+
+void
+tree_jit::visit_switch_case (tree_switch_case&)
+{
+  fail ();
+}
+
+void
+tree_jit::visit_switch_case_list (tree_switch_case_list&)
+{
+  fail ();
+}
+
+void
+tree_jit::visit_switch_command (tree_switch_command&)
+{
+  fail ();
+}
+
+void
+tree_jit::visit_try_catch_command (tree_try_catch_command&)
+{
+  fail ();
+}
+
+void
+tree_jit::visit_unwind_protect_command (tree_unwind_protect_command&)
+{
+  fail ();
+}
+
+void
+tree_jit::visit_while_command (tree_while_command&)
+{
+  fail ();
+}
+
+void
+tree_jit::visit_do_until_command (tree_do_until_command&)
+{
+  fail ();
+}
+
+void
+tree_jit::fail (void)
+{
+  throw jit_fail_exception ();
+}
+
+tree_jit::function_info::function_info (void) : function (0)
+{}
+
+tree_jit::function_info::function_info (jit_function fun,
+                                        const std::vector<std::string>& args,
+                                        const std::vector<bool>& arg_used) :
+  function (fun), arguments (args), argument_used (arg_used)
+{}
+
+bool tree_jit::function_info::execute ()
+{
+  if (! function)
+    return false;
+
+  // FIXME: we are doing hash lookups every time, this has got to be slow
+  unwind_protect up;
+  bool *args_defined = new bool[arguments.size ()];   // vector<bool> sucks
+  up.add_delete (args_defined);
+
+  std::vector<double>  args_values (arguments.size ());
+  for (size_t i = 0; i < arguments.size (); ++i)
+    {
+      octave_value ov = symbol_table::varval (arguments[i]);
+
+      if (argument_used[i])
+        {
+          if (! (ov.is_double_type () && ov.is_real_scalar ()))
+            return false;
+
+          args_defined[i] = ov.is_defined ();
+          args_values[i] = ov.double_value ();
+        }
+      else
+        args_defined[i] = false;
+    }
+
+  function (args_defined, &args_values[0]);
+
+  for (size_t i = 0; i < arguments.size (); ++i)
+    if (args_defined[i])
+      symbol_table::varref (arguments[i]) = octave_value (args_values[i]);
+
+  return true;
+}