Subversion Repositories openrisc_2011-10-31

/* Interprocedural analyses.

   Copyright (C) 2005, 2007, 2008, 2009

   Free Software Foundation, Inc.

This file is part of GCC.

GCC 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, or (at your option) any later

version.

GCC 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 GCC; see the file COPYING3.  If not see

<http://www.gnu.org/licenses/>.  */

#ifndef IPA_PROP_H

#define IPA_PROP_H

#include "tree.h"

#include "vec.h"

#include "cgraph.h"

/* The following definitions and interfaces are used by

   interprocedural analyses or parameters.  */

/* ipa-prop.c stuff (ipa-cp, indirect inlining):  */

/* A jump function for a callsite represents the values passed as actual

   arguments of the callsite. There are three main types of values :

   Pass-through - the caller's formal parameter is passed as an actual

                  argument, possibly one simple operation performed on it.

   Constant     - a constant (is_gimple_ip_invariant)is passed as an actual

                  argument.

   Unknown      - neither of the above.

   IPA_JF_CONST_MEMBER_PTR stands for C++ member pointers, other constants are

   represented with IPA_JF_CONST.

   In addition to "ordinary" pass through functions represented by

   IPA_JF_PASS_THROUGH, IPA_JF_ANCESTOR represents getting addresses of of

   ancestor fields in C++ (e.g. &this_1(D)->D.1766.D.1756).  */

enum jump_func_type

{

  IPA_JF_UNKNOWN = 0,  /* newly allocated and zeroed jump functions default */

  IPA_JF_CONST,

  IPA_JF_CONST_MEMBER_PTR,

  IPA_JF_PASS_THROUGH,

  IPA_JF_ANCESTOR

};

/* All formal parameters in the program have a lattice associated with it

   computed by the interprocedural stage of IPCP.

   There are three main values of the lattice:

   IPA_TOP - unknown,

   IPA_BOTTOM - non constant,

   IPA_CONST_VALUE - simple scalar constant,

   Cval of formal f will have a constant value if all callsites to this

   function have the same constant value passed to f.

   Integer and real constants are represented as IPA_CONST_VALUE.  */

enum ipa_lattice_type

{

  IPA_BOTTOM,

  IPA_CONST_VALUE,

  IPA_TOP

};

/* Structure holding data required to describe a pass-through jump function.  */

struct GTY(()) ipa_pass_through_data

{

  /* If an operation is to be performed on the original parameter, this is the

     second (constant) operand.  */

  tree operand;

  /* Number of the caller's formal parameter being passed.  */

  int formal_id;

  /* Operation that is performed on the argument before it is passed on.

     NOP_EXPR means no operation.  Otherwise oper must be a simple binary

     arithmetic operation where the caller's parameter is the first operand and

     operand field from this structure is the second one.  */

  enum tree_code operation;

};

/* Structure holding data required to describe and ancestor pass throu

   funkci.  */

struct GTY(()) ipa_ancestor_jf_data

{

  /* Offset of the field representing the ancestor.  */

  HOST_WIDE_INT offset;

  /* TYpe of the result.  */

  tree type;

  /* Number of the caller's formal parameter being passed.  */

  int formal_id;

};

/* Structure holding a C++ member pointer constant.  Holds a pointer to the

   method and delta offset.  */

struct GTY(()) ipa_member_ptr_cst

{

  tree pfn;

  tree delta;

};

/* A jump function for a callsite represents the values passed as actual

   arguments of the callsite. See enum jump_func_type for the various

   types of jump functions supported.  */

struct GTY (()) ipa_jump_func

{

  enum jump_func_type type;

  /* Represents a value of a jump function.  pass_through is used only in jump

     function context.  constant represents the actual constant in constant jump

     functions and member_cst holds constant c++ member functions.  */

  union jump_func_value

  {

    tree GTY ((tag ("IPA_JF_CONST"))) constant;

    struct ipa_pass_through_data GTY ((tag ("IPA_JF_PASS_THROUGH"))) pass_through;

    struct ipa_ancestor_jf_data GTY ((tag ("IPA_JF_ANCESTOR"))) ancestor;

    struct ipa_member_ptr_cst GTY ((tag ("IPA_JF_CONST_MEMBER_PTR"))) member_cst;

  } GTY ((desc ("%1.type"))) value;

};

/* All formal parameters in the program have a cval computed by

   the interprocedural stage of IPCP. See enum ipa_lattice_type for

   the various types of lattices supported */

struct ipcp_lattice

{

  enum ipa_lattice_type type;

  tree constant;

};

/* Each instance of the following  structure describes a statement that calls a

   function parameter.  Those referring  to statements within the same function

   are linked in a list.  */

struct ipa_param_call_note

{

  /* Expected number of executions: calculated in profile.c.  */

  gcov_type count;

  /* Linked list's next */

  struct ipa_param_call_note *next;

  /* Statement that contains the call to the parameter above.  */

  gimple stmt;

  /* When in LTO, we the above stmt will be NULL and we need an uid. */

  unsigned int lto_stmt_uid;

  /* Index of the parameter that is called.  */

  int formal_id;

  /* Expected frequency of executions within the function. see cgraph_edge in

     cgraph.h for more on this. */

  int frequency;

  /* Depth of loop nest, 1 means no loop nest.  */

  unsigned short int loop_nest;

  /* Set when we have already found the target to be a compile time constant

     and turned this into an edge or when the note was found unusable for some

     reason.  */

  bool processed;

};

/* Structure describing a single formal parameter.  */

struct ipa_param_descriptor

{

  /* IPA-CP lattice.  */

  struct ipcp_lattice ipcp_lattice;

  /* PARAM_DECL of this parameter.  */

  tree decl;

  /* Whether the value parameter has been modified within the function.  */

  unsigned modified : 1;

};

/* ipa_node_params stores information related to formal parameters of functions

   and some other information for interprocedural passes that operate on

   parameters (such as ipa-cp).  */

struct ipa_node_params

{

  /* Number of formal parameters of this function.  When set to 0,

     this function's parameters would not be analyzed by the different

     stages of IPA CP.  */

  int param_count;

  /* Pointer to an array of structures describing individual formal

     parameters.  */

  struct ipa_param_descriptor *params;

  /* List of structures enumerating calls to a formal parameter.  */

  struct ipa_param_call_note *param_calls;

  /* Only for versioned nodes this field would not be NULL,

     it points to the node that IPA cp cloned from.  */

  struct cgraph_node *ipcp_orig_node;

  /* Meaningful only for original functions.  Expresses the

     ratio between the direct calls and sum of all invocations of

     this function (given by profiling info).  It is used to calculate

     the profiling information of the original function and the versioned

     one.  */

  gcov_type count_scale;

  /* Whether this function is called with variable number of actual

     arguments.  */

  unsigned called_with_var_arguments : 1;

  /* Whether the modification analysis has already been performed. */

  unsigned modification_analysis_done : 1;

  /* Whether the param uses analysis has already been performed.  */

  unsigned uses_analysis_done : 1;

  /* Whether the function is enqueued in an ipa_func_list.  */

  unsigned node_enqueued : 1;

};

/* ipa_node_params access functions.  Please use these to access fields that

   are or will be shared among various passes.  */

/* Set the number of formal parameters. */

static inline void

ipa_set_param_count (struct ipa_node_params *info, int count)

{

  info->param_count = count;

}

/* Return the number of formal parameters. */

static inline int

ipa_get_param_count (struct ipa_node_params *info)

{

  return info->param_count;

}

/* Return the declaration of Ith formal parameter of the function corresponding

   to INFO.  Note there is no setter function as this array is built just once

   using ipa_initialize_node_params. */

static inline tree

ipa_get_param (struct ipa_node_params *info, int i)

{

  return info->params[i].decl;

}

/* Return the modification flag corresponding to the Ith formal parameter of

   the function associated with INFO.  Note that there is no setter method as

   the goal is to set all flags when building the array in

   ipa_detect_param_modifications.  */

static inline bool

ipa_is_param_modified (struct ipa_node_params *info, int i)

{

  return info->params[i].modified;

}

/* Flag this node as having callers with variable number of arguments.  */

static inline void

ipa_set_called_with_variable_arg (struct ipa_node_params *info)

{

  info->called_with_var_arguments = 1;

}

/* Have we detected this node was called with variable number of arguments? */

static inline bool

ipa_is_called_with_var_arguments (struct ipa_node_params *info)

{

  return info->called_with_var_arguments;

}

/* ipa_edge_args stores information related to a callsite and particularly

   its arguments. It is pointed to by a field in the

   callsite's corresponding cgraph_edge.  */

typedef struct GTY(()) ipa_edge_args

{

  /* Number of actual arguments in this callsite.  When set to 0,

     this callsite's parameters would not be analyzed by the different

     stages of IPA CP.  */

  int argument_count;

  /* Array of the callsite's jump function of each parameter.  */

  struct ipa_jump_func GTY ((length ("%h.argument_count"))) *jump_functions;

} ipa_edge_args_t;

/* ipa_edge_args access functions.  Please use these to access fields that

   are or will be shared among various passes.  */

/* Set the number of actual arguments. */

static inline void

ipa_set_cs_argument_count (struct ipa_edge_args *args, int count)

{

  args->argument_count = count;

}

/* Return the number of actual arguments. */

static inline int

ipa_get_cs_argument_count (struct ipa_edge_args *args)

{

  return args->argument_count;

}

/* Returns a pointer to the jump function for the ith argument.  Please note

   there is no setter function as jump functions are all set up in

   ipa_compute_jump_functions. */

static inline struct ipa_jump_func *

ipa_get_ith_jump_func (struct ipa_edge_args *args, int i)

{

  return &args->jump_functions[i];

}

/* Vectors need to have typedefs of structures.  */

typedef struct ipa_node_params ipa_node_params_t;

/* Types of vectors holding the infos.  */

DEF_VEC_O (ipa_node_params_t);

DEF_VEC_ALLOC_O (ipa_node_params_t, heap);

DEF_VEC_O (ipa_edge_args_t);

DEF_VEC_ALLOC_O (ipa_edge_args_t, gc);

/* Vector where the parameter infos are actually stored. */

extern VEC (ipa_node_params_t, heap) *ipa_node_params_vector;

/* Vector where the parameter infos are actually stored. */

extern GTY(()) VEC (ipa_edge_args_t, gc) *ipa_edge_args_vector;

/* Return the associated parameter/argument info corresponding to the given

   node/edge.  */

#define IPA_NODE_REF(NODE) (VEC_index (ipa_node_params_t, \

                                       ipa_node_params_vector, (NODE)->uid))

#define IPA_EDGE_REF(EDGE) (VEC_index (ipa_edge_args_t, \

                                       ipa_edge_args_vector, (EDGE)->uid))

/* This macro checks validity of index returned by

   ipa_get_param_decl_index function.  */

#define IS_VALID_JUMP_FUNC_INDEX(I) ((I) != -1)

/* Creating and freeing ipa_node_params and ipa_edge_args.  */

void ipa_create_all_node_params (void);

void ipa_create_all_edge_args (void);

void ipa_free_edge_args_substructures (struct ipa_edge_args *);

void ipa_free_node_params_substructures (struct ipa_node_params *);

void ipa_free_all_node_params (void);

void ipa_free_all_edge_args (void);

void free_all_ipa_structures_after_ipa_cp (void);

void free_all_ipa_structures_after_iinln (void);

void ipa_register_cgraph_hooks (void);

/* This function ensures the array of node param infos is big enough to

   accommodate a structure for all nodes and reallocates it if not.  */

static inline void

ipa_check_create_node_params (void)

{

  if (!ipa_node_params_vector)

    ipa_node_params_vector = VEC_alloc (ipa_node_params_t, heap,

                                        cgraph_max_uid);

  if (VEC_length (ipa_node_params_t, ipa_node_params_vector)

      <= (unsigned) cgraph_max_uid)

    VEC_safe_grow_cleared (ipa_node_params_t, heap,

                           ipa_node_params_vector, cgraph_max_uid + 1);

}

/* This function ensures the array of edge arguments infos is big enough to

   accommodate a structure for all edges and reallocates it if not.  */

static inline void

ipa_check_create_edge_args (void)

{

  if (!ipa_edge_args_vector)

    ipa_edge_args_vector = VEC_alloc (ipa_edge_args_t, gc,

                                      cgraph_edge_max_uid);

  if (VEC_length (ipa_edge_args_t, ipa_edge_args_vector)

      <=  (unsigned) cgraph_edge_max_uid)

    VEC_safe_grow_cleared (ipa_edge_args_t, gc, ipa_edge_args_vector,

                           cgraph_edge_max_uid + 1);

}

/* Returns true if the array of edge infos is large enough to accommodate an

   info for EDGE.  The main purpose of this function is that debug dumping

   function can check info availability without causing reallocations.  */

static inline bool

ipa_edge_args_info_available_for_edge_p (struct cgraph_edge *edge)

{

  return ((unsigned) edge->uid < VEC_length (ipa_edge_args_t,

                                             ipa_edge_args_vector));

}

/* A function list element.  It is used to create a temporary worklist used in

   the propagation stage of IPCP. (can be used for more IPA optimizations)  */

struct ipa_func_list

{

  struct cgraph_node *node;

  struct ipa_func_list *next;

};

/* ipa_func_list interface.  */

struct ipa_func_list *ipa_init_func_list (void);

void ipa_push_func_to_list_1 (struct ipa_func_list **, struct cgraph_node *,

                              struct ipa_node_params *);

struct cgraph_node *ipa_pop_func_from_list (struct ipa_func_list **);

/* Add cgraph NODE to the worklist WL if it is not already in one.  */

static inline void

ipa_push_func_to_list (struct ipa_func_list **wl, struct cgraph_node *node)

{

  struct ipa_node_params *info = IPA_NODE_REF (node);

  if (!info->node_enqueued)

    ipa_push_func_to_list_1 (wl, node, info);

}

/* Callsite related calculations.  */

void ipa_compute_jump_functions (struct cgraph_edge *);

void ipa_count_arguments (struct cgraph_edge *);

/* Function formal parameters related computations.  */

void ipa_initialize_node_params (struct cgraph_node *node);

void ipa_detect_param_modifications (struct cgraph_node *);

void ipa_analyze_params_uses (struct cgraph_node *);

bool ipa_propagate_indirect_call_infos (struct cgraph_edge *cs,

                                        VEC (cgraph_edge_p, heap) **new_edges);

/* Debugging interface.  */

void ipa_print_node_params (FILE *, struct cgraph_node *node);

void ipa_print_all_params (FILE *);

void ipa_print_node_jump_functions (FILE *f, struct cgraph_node *node);

void ipa_print_all_jump_functions (FILE * f);

/* Structure to describe transformations of formal parameters and actual

   arguments.  Each instance describes one new parameter and they are meant to

   be stored in a vector.  Additionally, most users will probably want to store

   adjustments about parameters that are being removed altogether so that SSA

   names belonging to them can be replaced by SSA names of an artificial

   variable.  */

struct ipa_parm_adjustment

{

  /* The original PARM_DECL itself, helpful for processing of the body of the

     function itself.  Intended for traversing function bodies.

     ipa_modify_formal_parameters, ipa_modify_call_arguments and

     ipa_combine_adjustments ignore this and use base_index.

     ipa_modify_formal_parameters actually sets this.  */

  tree base;

  /* Type of the new parameter.  However, if by_ref is true, the real type will

     be a pointer to this type.  */

  tree type;

  /* The new declaration when creating/replacing a parameter.  Created by

     ipa_modify_formal_parameters, useful for functions modifying the body

     accordingly. */

  tree reduction;

  /* New declaration of a substitute variable that we may use to replace all

     non-default-def ssa names when a parm decl is going away.  */

  tree new_ssa_base;

  /* If non-NULL and the original parameter is to be removed (copy_param below

     is NULL), this is going to be its nonlocalized vars value.  */

  tree nonlocal_value;

  /* Offset into the original parameter (for the cases when the new parameter

     is a component of an original one).  */

  HOST_WIDE_INT offset;

  /* Zero based index of the original parameter this one is based on.  (ATM

     there is no way to insert a new parameter out of the blue because there is

     no need but if it arises the code can be easily exteded to do so.)  */

  int base_index;

  /* This new parameter is an unmodified parameter at index base_index. */

  unsigned copy_param : 1;

  /* This adjustment describes a parameter that is about to be removed

     completely.  Most users will probably need to book keep those so that they

     don't leave behinfd any non default def ssa names belonging to them.  */

  unsigned remove_param : 1;

  /* The parameter is to be passed by reference.  */

  unsigned by_ref : 1;

};

typedef struct ipa_parm_adjustment ipa_parm_adjustment_t;

DEF_VEC_O (ipa_parm_adjustment_t);

DEF_VEC_ALLOC_O (ipa_parm_adjustment_t, heap);

typedef VEC (ipa_parm_adjustment_t, heap) *ipa_parm_adjustment_vec;

VEC(tree, heap) *ipa_get_vector_of_formal_parms (tree fndecl);

void ipa_modify_formal_parameters (tree fndecl, ipa_parm_adjustment_vec,

                                   const char *);

void ipa_modify_call_arguments (struct cgraph_edge *, gimple,

                                ipa_parm_adjustment_vec);

ipa_parm_adjustment_vec ipa_combine_adjustments (ipa_parm_adjustment_vec,

                                                 ipa_parm_adjustment_vec);

void ipa_dump_param_adjustments (FILE *, ipa_parm_adjustment_vec, tree);

void ipa_prop_write_jump_functions (cgraph_node_set set);

void ipa_prop_read_jump_functions (void);

void ipa_update_after_lto_read (void);

void lto_ipa_fixup_call_notes (struct cgraph_node *, gimple *);

/* From tree-sra.c:  */

bool build_ref_for_offset (tree *, tree, HOST_WIDE_INT, tree, bool);

#endif /* IPA_PROP_H */