[vala] (40 commits) Created branch wip/effectfree

[Luca Bruno <lucabru src gnome org>]

The branch 'wip/effectfree' was created.

Summary of new commits:

  ab2b587... Emit left-handed side of assignment when it's a field or pa
  504b069... codegen: Use lvalue of the assignment when emitting array a
  beb158a... codegen: Unset array_size_cvalue in load_variable
  79206b1... Add get_defined_variables in PostfixExpression
  cab7956... Set parent_node of the expression of delete statements
  bebeeea... Set parent_node of the postfix inner expression
  553df5c... Set lvalue to the inner expression of address-of expression
  752ef6a... Set lvalue to inner expression of method call that returns 
  5ec1e8a... Set lvalue to inner member access having type non-nullable 
  1757d2a... Set lvalue to inner expression when accessing array length 
  3e68e64... codegen: Cleanup emit_temp_var
  52ecb70... codegen: Add create_temp_value, load_temp_value and store_t
  1ac9855... codegen: Use temporary variables when accessing a variable
  b23fb26... codegen: Use temporary variables when accessing a property
  d681227... codegen: Make transform_value be effect-free
  ad01f6c... codegen: Make copy_value be effect-free
  21361e2... codegen: Drop useless temporary variable in array creation
  ffa9ad7... codegen: Drop useless temporary variable in simple assignme
  3055898... codegen: Cleanup simple assignment
  0abf5b0... codegen: Drop useless temporary variables when storing a pr
  afc7345... codegen: Drop useless temp variable when accessing base met
  44353ef... codegen: Drop useless temporary variable in visit_cast_expr
  5907565... codegen: Simplify emit of postfix expression
  a593193... codegen: Use create_temp_value in struct initializer
  dd41eef... codegen: Use create_temp_value in visit_object_creation_exp
  04fdf38... codegen: Use store_temp_value in visit_reference_transfer_e
  f974776... codegen: Use create_temp_value in visit_binary_expression
  dff2574... codegen: Use create_temp_value in handle_struct_argument
  d6224e3... codegen: Use create_temp_value in try_cast_value_to_type
  2a0c26e... codegen: Use create_temp_value in store_property
  7dcae5d... codegen: Use create_temp_value in visit_string_switch_state
  265d76e... codegen: Use store_temp_value in visit_return_statement
  8b116bd... codegen: Replace temp_ref_vars with temp_ref_values using T
  9fd1bff... codegen: Use create_temp_value in copy_value of array modul
  1641fb3... codegen: Use create_temp_value in copy_value
  93c4b5c... codegen: Use create_temp_value in try_cast_variant_to_type
  1a3325e... codegen: Use store_temp_value in visit_end_full_expression
  34a9e3a... codegen: Avoid useless temporary variable in visit_end_full
  6681feb... codegen: Add lvalue field to GLibValue
  30d0b71... codegen: Use GLibValue.lvalue when taking the address of an