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8sa1-gcc/gcc/cp/optimize.c
Jakub Jelinek 64b9f19994 Clarify comment. 
From-SVN: r39320
2001-01-28 15:04:19 +01:00

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/* Perform optimizations on tree structure.
Copyright (C) 1998, 1999, 2000 Free Software Foundation, Inc.
Written by Mark Michell (mark@codesourcery.com).
This file is part of GNU CC.
GNU CC 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 2, or (at your option)
any later version.
GNU CC 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 GNU CC; see the file COPYING. If not, write to the Free
Software Foundation, 59 Temple Place - Suite 330, Boston, MA
02111-1307, USA. */
#include "config.h"
#include "system.h"
#include "tree.h"
#include "cp-tree.h"
#include "rtl.h"
#include "insn-config.h"
#include "input.h"
#include "integrate.h"
#include "varray.h"
/* To Do:
o In order to make inlining-on-trees work, we pessimized
function-local static constants. In particular, they are now
always output, even when not addressed. Fix this by treating
function-local static constants just like global static
constants; the back-end already knows not to output them if they
are not needed.
o Provide heuristics to clamp inlining of recursive template
calls? */
/* Data required for function inlining. */
typedef struct inline_data
{
/* A stack of the functions we are inlining. For example, if we are
compiling `f', which calls `g', which calls `h', and we are
inlining the body of `h', the stack will contain, `h', followed
by `g', followed by `f'. */
varray_type fns;
/* The label to jump to when a return statement is encountered. If
this value is NULL, then return statements will simply be
remapped as return statements, rather than as jumps. */
tree ret_label;
/* The map from local declarations in the inlined function to
equivalents in the function into which it is being inlined. */
splay_tree decl_map;
/* Nonzero if we are currently within the cleanup for a
TARGET_EXPR. */
int in_target_cleanup_p;
/* A stack of the TARGET_EXPRs that we are currently processing. */
varray_type target_exprs;
} inline_data;
/* Prototypes. */
static tree initialize_inlined_parameters PARAMS ((inline_data *, tree, tree));
static tree declare_return_variable PARAMS ((inline_data *, tree *));
static tree copy_body_r PARAMS ((tree *, int *, void *));
static tree copy_body PARAMS ((inline_data *));
static tree expand_call_inline PARAMS ((tree *, int *, void *));
static void expand_calls_inline PARAMS ((tree *, inline_data *));
static int inlinable_function_p PARAMS ((tree, inline_data *));
static tree remap_decl PARAMS ((tree, inline_data *));
static void remap_block PARAMS ((tree, tree, inline_data *));
static void copy_scope_stmt PARAMS ((tree *, int *, inline_data *));
static tree calls_setjmp_r PARAMS ((tree *, int *, void *));
/* Remap DECL during the copying of the BLOCK tree for the function.
DATA is really an `inline_data *'. */
static tree
remap_decl (decl, id)
tree decl;
inline_data *id;
{
splay_tree_node n;
tree fn;
/* We only remap local variables in the current function. */
fn = VARRAY_TOP_TREE (id->fns);
if (!nonstatic_local_decl_p (decl) || DECL_CONTEXT (decl) != fn)
return NULL_TREE;
/* See if we have remapped this declaration. */
n = splay_tree_lookup (id->decl_map, (splay_tree_key) decl);
/* If we didn't already have an equivalent for this declaration,
create one now. */
if (!n)
{
tree t;
/* Make a copy of the variable or label. */
t = copy_decl_for_inlining (decl, fn,
VARRAY_TREE (id->fns, 0));
/* The decl T could be a dynamic array or other variable size type,
in which case some fields need to be remapped because they may
contain SAVE_EXPRs. */
walk_tree (&DECL_SIZE (t), copy_body_r, id, NULL);
walk_tree (&DECL_SIZE_UNIT (t), copy_body_r, id, NULL);
if (TREE_TYPE (t) && TREE_CODE (TREE_TYPE (t)) == ARRAY_TYPE
&& TYPE_DOMAIN (TREE_TYPE (t)))
{
TREE_TYPE (t) = copy_node (TREE_TYPE (t));
TYPE_DOMAIN (TREE_TYPE (t))
= copy_node (TYPE_DOMAIN (TREE_TYPE (t)));
walk_tree (&TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (t))),
copy_body_r, id, NULL);
}
/* Remember it, so that if we encounter this local entity
again we can reuse this copy. */
n = splay_tree_insert (id->decl_map,
(splay_tree_key) decl,
(splay_tree_value) t);
}
return (tree) n->value;
}
/* Copy the SCOPE_STMT_BLOCK associated with SCOPE_STMT to contain
remapped versions of the variables therein. And hook the new block
into the block-tree. If non-NULL, the DECLS are declarations to
add to use instead of the BLOCK_VARS in the old block. */
static void
remap_block (scope_stmt, decls, id)
tree scope_stmt;
tree decls;
inline_data *id;
{
/* We cannot do this in the cleanup for a TARGET_EXPR since we do
not know whether or not expand_expr will actually write out the
code we put there. If it does not, then we'll have more BLOCKs
than block-notes, and things will go awry. At some point, we
should make the back-end handle BLOCK notes in a tidier way,
without requiring a strict correspondence to the block-tree; then
this check can go. */
if (id->in_target_cleanup_p)
{
SCOPE_STMT_BLOCK (scope_stmt) = NULL_TREE;
return;
}
/* If this is the beginning of a scope, remap the associated BLOCK. */
if (SCOPE_BEGIN_P (scope_stmt) && SCOPE_STMT_BLOCK (scope_stmt))
{
tree old_block;
tree new_block;
tree old_var;
tree *first_block;
tree fn;
/* Make the new block. */
old_block = SCOPE_STMT_BLOCK (scope_stmt);
new_block = make_node (BLOCK);
TREE_USED (new_block) = TREE_USED (old_block);
BLOCK_ABSTRACT_ORIGIN (new_block) = old_block;
SCOPE_STMT_BLOCK (scope_stmt) = new_block;
/* Remap its variables. */
for (old_var = decls ? decls : BLOCK_VARS (old_block);
old_var;
old_var = TREE_CHAIN (old_var))
{
tree new_var;
/* Remap the variable. */
new_var = remap_decl (old_var, id);
/* If we didn't remap this variable, so we can't mess with
its TREE_CHAIN. If we remapped this variable to
something other than a declaration (say, if we mapped it
to a constant), then we must similarly omit any mention
of it here. */
if (!new_var || !DECL_P (new_var))
;
else
{
TREE_CHAIN (new_var) = BLOCK_VARS (new_block);
BLOCK_VARS (new_block) = new_var;
}
}
/* We put the BLOCK_VARS in reverse order; fix that now. */
BLOCK_VARS (new_block) = nreverse (BLOCK_VARS (new_block));
/* Attach this new block after the DECL_INITIAL block for the
function into which this block is being inlined. In
rest_of_compilation we will straighten out the BLOCK tree. */
fn = VARRAY_TREE (id->fns, 0);
if (DECL_INITIAL (fn))
first_block = &BLOCK_CHAIN (DECL_INITIAL (fn));
else
first_block = &DECL_INITIAL (fn);
BLOCK_CHAIN (new_block) = *first_block;
*first_block = new_block;
/* Remember the remapped block. */
splay_tree_insert (id->decl_map,
(splay_tree_key) old_block,
(splay_tree_value) new_block);
}
/* If this is the end of a scope, set the SCOPE_STMT_BLOCK to be the
remapped block. */
else if (SCOPE_END_P (scope_stmt) && SCOPE_STMT_BLOCK (scope_stmt))
{
splay_tree_node n;
/* Find this block in the table of remapped things. */
n = splay_tree_lookup (id->decl_map,
(splay_tree_key) SCOPE_STMT_BLOCK (scope_stmt));
my_friendly_assert (n != NULL, 19991203);
SCOPE_STMT_BLOCK (scope_stmt) = (tree) n->value;
}
}
/* Copy the SCOPE_STMT pointed to by TP. */
static void
copy_scope_stmt (tp, walk_subtrees, id)
tree *tp;
int *walk_subtrees;
inline_data *id;
{
tree block;
/* Remember whether or not this statement was nullified. When
making a copy, copy_tree_r always sets SCOPE_NULLIFIED_P (and
doesn't copy the SCOPE_STMT_BLOCK) to free callers from having to
deal with copying BLOCKs if they do not wish to do so. */
block = SCOPE_STMT_BLOCK (*tp);
/* Copy (and replace) the statement. */
copy_tree_r (tp, walk_subtrees, NULL);
/* Restore the SCOPE_STMT_BLOCK. */
SCOPE_STMT_BLOCK (*tp) = block;
/* Remap the associated block. */
remap_block (*tp, NULL_TREE, id);
}
/* Called from copy_body via walk_tree. DATA is really an
`inline_data *'. */
static tree
copy_body_r (tp, walk_subtrees, data)
tree *tp;
int *walk_subtrees;
void *data;
{
inline_data* id;
tree fn;
/* Set up. */
id = (inline_data *) data;
fn = VARRAY_TOP_TREE (id->fns);
/* All automatic variables should have a DECL_CONTEXT indicating
what function they come from. */
if ((TREE_CODE (*tp) == VAR_DECL || TREE_CODE (*tp) == LABEL_DECL)
&& DECL_NAMESPACE_SCOPE_P (*tp))
my_friendly_assert (DECL_EXTERNAL (*tp) || TREE_STATIC (*tp),
19991113);
/* If this is a RETURN_STMT, change it into an EXPR_STMT and a
GOTO_STMT with the RET_LABEL as its target. */
if (TREE_CODE (*tp) == RETURN_STMT && id->ret_label)
{
tree return_stmt = *tp;
tree goto_stmt;
/* Build the GOTO_STMT. */
goto_stmt = build_stmt (GOTO_STMT, id->ret_label);
TREE_CHAIN (goto_stmt) = TREE_CHAIN (return_stmt);
/* If we're returning something, just turn that into an
assignment into the equivalent of the original
RESULT_DECL. */
if (RETURN_EXPR (return_stmt))
{
*tp = build_stmt (EXPR_STMT,
RETURN_EXPR (return_stmt));
STMT_IS_FULL_EXPR_P (*tp) = 1;
/* And then jump to the end of the function. */
TREE_CHAIN (*tp) = goto_stmt;
}
/* If we're not returning anything just do the jump. */
else
*tp = goto_stmt;
}
/* Local variables and labels need to be replaced by equivalent
variables. We don't want to copy static variables; there's only
one of those, no matter how many times we inline the containing
function. */
else if (nonstatic_local_decl_p (*tp) && DECL_CONTEXT (*tp) == fn)
{
tree new_decl;
/* Remap the declaration. */
new_decl = remap_decl (*tp, id);
my_friendly_assert (new_decl != NULL_TREE, 19991203);
/* Replace this variable with the copy. */
STRIP_TYPE_NOPS (new_decl);
*tp = new_decl;
}
else if (nonstatic_local_decl_p (*tp)
&& DECL_CONTEXT (*tp) != VARRAY_TREE (id->fns, 0))
my_friendly_abort (0);
else if (TREE_CODE (*tp) == SAVE_EXPR)
remap_save_expr (tp, id->decl_map, VARRAY_TREE (id->fns, 0),
walk_subtrees);
else if (TREE_CODE (*tp) == UNSAVE_EXPR)
/* UNSAVE_EXPRs should not be generated until expansion time. */
my_friendly_abort (19991113);
/* For a SCOPE_STMT, we must copy the associated block so that we
can write out debugging information for the inlined variables. */
else if (TREE_CODE (*tp) == SCOPE_STMT && !id->in_target_cleanup_p)
copy_scope_stmt (tp, walk_subtrees, id);
/* Otherwise, just copy the node. Note that copy_tree_r already
knows not to copy VAR_DECLs, etc., so this is safe. */
else
{
copy_tree_r (tp, walk_subtrees, NULL);
/* The copied TARGET_EXPR has never been expanded, even if the
original node was expanded already. */
if (TREE_CODE (*tp) == TARGET_EXPR && TREE_OPERAND (*tp, 3))
{
TREE_OPERAND (*tp, 1) = TREE_OPERAND (*tp, 3);
TREE_OPERAND (*tp, 3) = NULL_TREE;
}
else if (TREE_CODE (*tp) == MODIFY_EXPR
&& TREE_OPERAND (*tp, 0) == TREE_OPERAND (*tp, 1)
&& nonstatic_local_decl_p (TREE_OPERAND (*tp, 0))
&& DECL_CONTEXT (TREE_OPERAND (*tp, 0)) == fn)
{
/* Some assignments VAR = VAR; don't generate any rtl code
and thus don't count as variable modification. Avoid
keeping bogosities like 0 = 0. */
tree decl = TREE_OPERAND (*tp, 0), value;
splay_tree_node n;
n = splay_tree_lookup (id->decl_map, (splay_tree_key) decl);
if (n)
{
value = (tree) n->value;
STRIP_TYPE_NOPS (value);
if (TREE_CONSTANT (value) || TREE_READONLY_DECL_P (value))
*tp = value;
}
}
}
/* Keep iterating. */
return NULL_TREE;
}
/* Make a copy of the body of FN so that it can be inserted inline in
another function. */
static tree
copy_body (id)
inline_data *id;
{
tree body;
body = DECL_SAVED_TREE (VARRAY_TOP_TREE (id->fns));
walk_tree (&body, copy_body_r, id, NULL);
return body;
}
/* Generate code to initialize the parameters of the function at the
top of the stack in ID from the ARGS (presented as a TREE_LIST). */
static tree
initialize_inlined_parameters (id, args, fn)
inline_data *id;
tree args;
tree fn;
{
tree init_stmts;
tree parms;
tree a;
tree p;
/* Figure out what the parameters are. */
parms = DECL_ARGUMENTS (fn);
/* Start with no initializations whatsoever. */
init_stmts = NULL_TREE;
/* Loop through the parameter declarations, replacing each with an
equivalent VAR_DECL, appropriately initialized. */
for (p = parms, a = args; p; a = TREE_CHAIN (a), p = TREE_CHAIN (p))
{
tree init_stmt;
tree var;
tree value;
/* Find the initializer. */
value = TREE_VALUE (a);
/* If the parameter is never assigned to, we may not need to
create a new variable here at all. Instead, we may be able
to just use the argument value. */
if (TREE_READONLY (p)
&& !TREE_ADDRESSABLE (p)
&& !TREE_SIDE_EFFECTS (value))
{
/* Simplify the value, if possible. */
value = fold (decl_constant_value (value));
/* We can't risk substituting complex expressions. They
might contain variables that will be assigned to later.
Theoretically, we could check the expression to see if
all of the variables that determine its value are
read-only, but we don't bother. */
if (TREE_CONSTANT (value) || TREE_READONLY_DECL_P (value))
{
/* If this is a declaration, wrap it a NOP_EXPR so that
we don't try to put the VALUE on the list of
BLOCK_VARS. */
if (DECL_P (value))
value = build1 (NOP_EXPR, TREE_TYPE (value), value);
splay_tree_insert (id->decl_map,
(splay_tree_key) p,
(splay_tree_value) value);
continue;
}
}
/* Make an equivalent VAR_DECL. */
var = copy_decl_for_inlining (p, fn, VARRAY_TREE (id->fns, 0));
/* Register the VAR_DECL as the equivalent for the PARM_DECL;
that way, when the PARM_DECL is encountered, it will be
automatically replaced by the VAR_DECL. */
splay_tree_insert (id->decl_map,
(splay_tree_key) p,
(splay_tree_value) var);
/* Declare this new variable. */
init_stmt = build_stmt (DECL_STMT, var);
TREE_CHAIN (init_stmt) = init_stmts;
init_stmts = init_stmt;
/* Initialize this VAR_DECL from the equivalent argument. If
the argument is an object, created via a constructor or copy,
this will not result in an extra copy: the TARGET_EXPR
representing the argument will be bound to VAR, and the
object will be constructed in VAR. */
if (! TYPE_NEEDS_CONSTRUCTING (TREE_TYPE (p)))
DECL_INITIAL (var) = value;
else
{
init_stmt = build_stmt (EXPR_STMT,
build (INIT_EXPR, TREE_TYPE (p),
var, value));
/* Add this initialization to the list. Note that we want the
declaration *after* the initialization because we are going
to reverse all the initialization statements below. */
TREE_CHAIN (init_stmt) = init_stmts;
init_stmts = init_stmt;
}
}
/* The initialization statements have been built up in reverse
order. Straighten them out now. */
return nreverse (init_stmts);
}
/* Declare a return variable to replace the RESULT_DECL for the
function we are calling. An appropriate DECL_STMT is returned.
The USE_STMT is filled in to contain a use of the declaration to
indicate the return value of the function. */
static tree
declare_return_variable (id, use_stmt)
struct inline_data *id;
tree *use_stmt;
{
tree fn = VARRAY_TOP_TREE (id->fns);
tree result = DECL_RESULT (fn);
tree var;
int aggregate_return_p;
/* We don't need to do anything for functions that don't return
anything. */
if (!result || VOID_TYPE_P (TREE_TYPE (result)))
{
*use_stmt = NULL_TREE;
return NULL_TREE;
}
/* Figure out whether or not FN returns an aggregate. */
aggregate_return_p = IS_AGGR_TYPE (TREE_TYPE (result));
/* If FN returns an aggregate then the caller will always create the
temporary (using a TARGET_EXPR) and the call will be the
initializing expression for the TARGET_EXPR. If we were just to
create a new VAR_DECL here, then the result of this function
would be copied (bitwise) into the variable initialized by the
TARGET_EXPR. That's incorrect, so we must transform any
references to the RESULT into references to the target. */
if (aggregate_return_p)
{
my_friendly_assert (id->target_exprs->elements_used != 0,
20000430);
var = TREE_OPERAND (VARRAY_TOP_TREE (id->target_exprs), 0);
my_friendly_assert
(same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (var),
TREE_TYPE (result)),
20000430);
}
/* Otherwise, make an appropriate copy. */
else
var = copy_decl_for_inlining (result, fn, VARRAY_TREE (id->fns, 0));
/* Register the VAR_DECL as the equivalent for the RESULT_DECL; that
way, when the RESULT_DECL is encountered, it will be
automatically replaced by the VAR_DECL. */
splay_tree_insert (id->decl_map,
(splay_tree_key) result,
(splay_tree_value) var);
/* Build the USE_STMT. */
*use_stmt = build_stmt (EXPR_STMT, var);
/* Build the declaration statement if FN does not return an
aggregate. */
if (!aggregate_return_p)
return build_stmt (DECL_STMT, var);
/* If FN does return an aggregate, there's no need to declare the
return variable; we're using a variable in our caller's frame. */
else
return NULL_TREE;
}
/* Returns non-zero if FN is a function that can be inlined. */
static int
inlinable_function_p (fn, id)
tree fn;
inline_data *id;
{
int inlinable;
/* If we've already decided this function shouldn't be inlined,
there's no need to check again. */
if (DECL_UNINLINABLE (fn))
return 0;
/* Assume it is not inlinable. */
inlinable = 0;
/* If we're not inlining things, then nothing is inlinable. */
if (!flag_inline_trees)
;
/* If the function was not declared `inline', then we don't inline
it. */
else if (!DECL_INLINE (fn))
;
/* We can't inline varargs functions. */
else if (varargs_function_p (fn))
;
/* All is well. We can inline this function. Traditionally, GCC
has refused to inline functions using alloca, or functions whose
values are returned in a PARALLEL, and a few other such obscure
conditions. We are not equally constrained at the tree level. */
else
inlinable = 1;
/* Squirrel away the result so that we don't have to check again. */
DECL_UNINLINABLE (fn) = !inlinable;
/* We can inline a template instantiation only if it's fully
instantiated. */
if (inlinable
&& DECL_TEMPLATE_INFO (fn)
&& TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (fn)))
{
fn = instantiate_decl (fn, /*defer_ok=*/0);
inlinable = !TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (fn));
}
/* If we don't have the function body available, we can't inline
it. */
if (!DECL_SAVED_TREE (fn))
inlinable = 0;
/* Don't do recursive inlining, either. We don't record this in
DECL_UNLINABLE; we may be able to inline this function later. */
if (inlinable)
{
size_t i;
for (i = 0; i < id->fns->elements_used; ++i)
if (VARRAY_TREE (id->fns, i) == fn)
inlinable = 0;
}
/* Return the result. */
return inlinable;
}
/* If *TP is a CALL_EXPR, replace it with its inline expansion. */
static tree
expand_call_inline (tp, walk_subtrees, data)
tree *tp;
int *walk_subtrees;
void *data;
{
inline_data *id;
tree t;
tree expr;
tree chain;
tree fn;
tree scope_stmt;
tree use_stmt;
tree arg_inits;
tree *inlined_body;
splay_tree st;
/* See what we've got. */
id = (inline_data *) data;
t = *tp;
/* Recurse, but letting recursive invocations know that we are
inside the body of a TARGET_EXPR. */
if (TREE_CODE (*tp) == TARGET_EXPR)
{
int i, len = first_rtl_op (TARGET_EXPR);
/* We're walking our own subtrees. */
*walk_subtrees = 0;
/* Push *TP on the stack of pending TARGET_EXPRs. */
VARRAY_PUSH_TREE (id->target_exprs, *tp);
/* Actually walk over them. This loop is the body of
walk_trees, omitting the case where the TARGET_EXPR
itself is handled. */
for (i = 0; i < len; ++i)
{
if (i == 2)
++id->in_target_cleanup_p;
walk_tree (&TREE_OPERAND (*tp, i), expand_call_inline, data,
NULL);
if (i == 2)
--id->in_target_cleanup_p;
}
/* We're done with this TARGET_EXPR now. */
VARRAY_POP (id->target_exprs);
return NULL_TREE;
}
/* From here on, we're only interested in CALL_EXPRs. */
if (TREE_CODE (t) != CALL_EXPR)
return NULL_TREE;
/* First, see if we can figure out what function is being called.
If we cannot, then there is no hope of inlining the function. */
fn = get_callee_fndecl (t);
if (!fn)
return NULL_TREE;
/* Don't try to inline functions that are not well-suited to
inlining. */
if (!inlinable_function_p (fn, id))
return NULL_TREE;
/* Set the current filename and line number to the function we are
inlining so that when we create new _STMT nodes here they get
line numbers corresponding to the function we are calling. We
wrap the whole inlined body in an EXPR_WITH_FILE_AND_LINE as well
because individual statements don't record the filename. */
push_srcloc (fn->decl.filename, fn->decl.linenum);
/* Build a statement-expression containing code to initialize the
arguments, the actual inline expansion of the body, and a label
for the return statements within the function to jump to. The
type of the statement expression is the return type of the
function call. */
expr = build_min (STMT_EXPR, TREE_TYPE (TREE_TYPE (fn)), NULL_TREE);
/* Local declarations will be replaced by their equivalents in this
map. */
st = id->decl_map;
id->decl_map = splay_tree_new (splay_tree_compare_pointers,
NULL, NULL);
/* Initialize the parameters. */
arg_inits = initialize_inlined_parameters (id, TREE_OPERAND (t, 1), fn);
/* Expand any inlined calls in the initializers. Do this before we
push FN on the stack of functions we are inlining; we want to
inline calls to FN that appear in the initializers for the
parameters. */
expand_calls_inline (&arg_inits, id);
/* And add them to the tree. */
STMT_EXPR_STMT (expr) = chainon (STMT_EXPR_STMT (expr), arg_inits);
/* Record the function we are about to inline so that we can avoid
recursing into it. */
VARRAY_PUSH_TREE (id->fns, fn);
/* Return statements in the function body will be replaced by jumps
to the RET_LABEL. */
id->ret_label = build_decl (LABEL_DECL, NULL_TREE, NULL_TREE);
DECL_CONTEXT (id->ret_label) = VARRAY_TREE (id->fns, 0);
/* Create a block to put the parameters in. We have to do this
after the parameters have been remapped because remapping
parameters is different from remapping ordinary variables. */
scope_stmt = build_stmt (SCOPE_STMT, DECL_INITIAL (fn));
SCOPE_BEGIN_P (scope_stmt) = 1;
SCOPE_NO_CLEANUPS_P (scope_stmt) = 1;
remap_block (scope_stmt, DECL_ARGUMENTS (fn), id);
TREE_CHAIN (scope_stmt) = STMT_EXPR_STMT (expr);
STMT_EXPR_STMT (expr) = scope_stmt;
/* Tell the debugging backends that this block represents the
outermost scope of the inlined function. */
if (SCOPE_STMT_BLOCK (scope_stmt))
BLOCK_ABSTRACT_ORIGIN (SCOPE_STMT_BLOCK (scope_stmt)) = DECL_ORIGIN (fn);
/* Declare the return variable for the function. */
STMT_EXPR_STMT (expr)
= chainon (STMT_EXPR_STMT (expr),
declare_return_variable (id, &use_stmt));
/* After we've initialized the parameters, we insert the body of the
function itself. */
inlined_body = &STMT_EXPR_STMT (expr);
while (*inlined_body)
inlined_body = &TREE_CHAIN (*inlined_body);
*inlined_body = copy_body (id);
/* Close the block for the parameters. */
scope_stmt = build_stmt (SCOPE_STMT, DECL_INITIAL (fn));
SCOPE_NO_CLEANUPS_P (scope_stmt) = 1;
my_friendly_assert (DECL_INITIAL (fn)
&& TREE_CODE (DECL_INITIAL (fn)) == BLOCK,
19991203);
remap_block (scope_stmt, NULL_TREE, id);
STMT_EXPR_STMT (expr)
= chainon (STMT_EXPR_STMT (expr), scope_stmt);
/* After the body of the function comes the RET_LABEL. This must come
before we evaluate the returned value below, because that evalulation
may cause RTL to be generated. */
STMT_EXPR_STMT (expr)
= chainon (STMT_EXPR_STMT (expr),
build_stmt (LABEL_STMT, id->ret_label));
/* Finally, mention the returned value so that the value of the
statement-expression is the returned value of the function. */
STMT_EXPR_STMT (expr) = chainon (STMT_EXPR_STMT (expr), use_stmt);
/* Clean up. */
splay_tree_delete (id->decl_map);
id->decl_map = st;
/* The new expression has side-effects if the old one did. */
TREE_SIDE_EFFECTS (expr) = TREE_SIDE_EFFECTS (t);
/* Replace the call by the inlined body. Wrap it in an
EXPR_WITH_FILE_LOCATION so that we'll get debugging line notes
pointing to the right place. */
chain = TREE_CHAIN (*tp);
*tp = build_expr_wfl (expr, DECL_SOURCE_FILE (fn), DECL_SOURCE_LINE (fn),
/*col=*/0);
EXPR_WFL_EMIT_LINE_NOTE (*tp) = 1;
TREE_CHAIN (*tp) = chain;
pop_srcloc ();
/* If the value of the new expression is ignored, that's OK. We
don't warn about this for CALL_EXPRs, so we shouldn't warn about
the equivalent inlined version either. */
TREE_USED (*tp) = 1;
/* Recurse into the body of the just inlined function. */
expand_calls_inline (inlined_body, id);
VARRAY_POP (id->fns);
/* Don't walk into subtrees. We've already handled them above. */
*walk_subtrees = 0;
/* Keep iterating. */
return NULL_TREE;
}
/* Walk over the entire tree *TP, replacing CALL_EXPRs with inline
expansions as appropriate. */
static void
expand_calls_inline (tp, id)
tree *tp;
inline_data *id;
{
/* Search through *TP, replacing all calls to inline functions by
appropriate equivalents. */
walk_tree (tp, expand_call_inline, id, NULL);
}
/* Optimize the body of FN. */
void
optimize_function (fn)
tree fn;
{
/* While in this function, we may choose to go off and compile
another function. For example, we might instantiate a function
in the hopes of inlining it. Normally, that wouldn't trigger any
actual RTL code-generation -- but it will if the template is
actually needed. (For example, if it's address is taken, or if
some other function already refers to the template.) If
code-generation occurs, then garbage collection will occur, so we
must protect ourselves, just as we do while building up the body
of the function. */
++function_depth;
/* Expand calls to inline functions. */
if (flag_inline_trees)
{
inline_data id;
tree prev_fn;
struct saved_scope *s;
/* Clear out ID. */
memset (&id, 0, sizeof (id));
/* Don't allow recursion into FN. */
VARRAY_TREE_INIT (id.fns, 32, "fns");
VARRAY_PUSH_TREE (id.fns, fn);
/* Or any functions that aren't finished yet. */
prev_fn = NULL_TREE;
if (current_function_decl)
{
VARRAY_PUSH_TREE (id.fns, current_function_decl);
prev_fn = current_function_decl;
}
for (s = scope_chain; s; s = s->prev)
if (s->function_decl && s->function_decl != prev_fn)
{
VARRAY_PUSH_TREE (id.fns, s->function_decl);
prev_fn = s->function_decl;
}
/* Create the stack of TARGET_EXPRs. */
VARRAY_TREE_INIT (id.target_exprs, 32, "target_exprs");
/* Replace all calls to inline functions with the bodies of those
functions. */
expand_calls_inline (&DECL_SAVED_TREE (fn), &id);
/* Clean up. */
VARRAY_FREE (id.fns);
VARRAY_FREE (id.target_exprs);
}
/* Undo the call to ggc_push_context above. */
--function_depth;
}
/* Called from calls_setjmp_p via walk_tree. */
static tree
calls_setjmp_r (tp, walk_subtrees, data)
tree *tp;
int *walk_subtrees ATTRIBUTE_UNUSED;
void *data ATTRIBUTE_UNUSED;
{
/* We're only interested in FUNCTION_DECLS. */
if (TREE_CODE (*tp) != FUNCTION_DECL)
return NULL_TREE;
return setjmp_call_p (*tp) ? *tp : NULL_TREE;
}
/* Returns non-zero if FN calls `setjmp' or some other function that
can return more than once. This function is conservative; it may
occasionally return a non-zero value even when FN does not actually
call `setjmp'. */
int
calls_setjmp_p (fn)
tree fn;
{
return walk_tree_without_duplicates (&DECL_SAVED_TREE (fn),
calls_setjmp_r,
NULL) != NULL_TREE;
}
/* FN is a function that has a complete body. Clone the body as
necessary. Returns non-zero if there's no longer any need to
process the main body. */
int
maybe_clone_body (fn)
tree fn;
{
inline_data id;
tree clone;
/* We don't clone constructors and destructors under the old ABI. */
if (!flag_new_abi)
return 0;
/* We only clone constructors and destructors. */
if (!DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn)
&& !DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn))
return 0;
/* We know that any clones immediately follow FN in the TYPE_METHODS
list. */
for (clone = TREE_CHAIN (fn);
clone && DECL_CLONED_FUNCTION_P (clone);
clone = TREE_CHAIN (clone))
{
tree parm;
tree clone_parm;
int parmno;
/* Update CLONE's source position information to match FN's. */
DECL_SOURCE_FILE (clone) = DECL_SOURCE_FILE (fn);
DECL_SOURCE_LINE (clone) = DECL_SOURCE_LINE (fn);
DECL_INLINE (clone) = DECL_INLINE (fn);
DECL_THIS_INLINE (clone) = DECL_THIS_INLINE (fn);
DECL_COMDAT (clone) = DECL_COMDAT (fn);
DECL_WEAK (clone) = DECL_WEAK (fn);
DECL_ONE_ONLY (clone) = DECL_ONE_ONLY (fn);
DECL_SECTION_NAME (clone) = DECL_SECTION_NAME (fn);
DECL_USE_TEMPLATE (clone) = DECL_USE_TEMPLATE (fn);
DECL_EXTERNAL (clone) = DECL_EXTERNAL (fn);
DECL_INTERFACE_KNOWN (clone) = DECL_INTERFACE_KNOWN (fn);
DECL_NOT_REALLY_EXTERN (clone) = DECL_NOT_REALLY_EXTERN (fn);
/* Start processing the function. */
push_to_top_level ();
start_function (NULL_TREE, clone, NULL_TREE, SF_PRE_PARSED);
/* Just clone the body, as if we were making an inline call.
But, remap the parameters in the callee to the parameters of
caller. If there's an in-charge parameter, map it to an
appropriate constant. */
memset (&id, 0, sizeof (id));
VARRAY_TREE_INIT (id.fns, 2, "fns");
VARRAY_PUSH_TREE (id.fns, clone);
VARRAY_PUSH_TREE (id.fns, fn);
/* Remap the parameters. */
id.decl_map = splay_tree_new (splay_tree_compare_pointers,
NULL, NULL);
for (parmno = 0,
parm = DECL_ARGUMENTS (fn),
clone_parm = DECL_ARGUMENTS (clone);
parm;
++parmno,
parm = TREE_CHAIN (parm))
{
/* Map the in-charge parameter to an appropriate constant. */
if (DECL_HAS_IN_CHARGE_PARM_P (fn) && parmno == 1)
{
tree in_charge;
in_charge = in_charge_arg_for_name (DECL_NAME (clone));
splay_tree_insert (id.decl_map,
(splay_tree_key) parm,
(splay_tree_value) in_charge);
/* For a subobject constructor or destructor, the next
argument is the VTT parameter. Remap the VTT_PARM
from the CLONE to this parameter. */
if (DECL_NEEDS_VTT_PARM_P (clone))
{
splay_tree_insert (id.decl_map,
(splay_tree_key) DECL_VTT_PARM (fn),
(splay_tree_value) clone_parm);
splay_tree_insert (id.decl_map,
(splay_tree_key) DECL_USE_VTT_PARM (fn),
(splay_tree_value) boolean_true_node);
clone_parm = TREE_CHAIN (clone_parm);
}
/* Otherwise, map the VTT parameter to `NULL'. */
else if (DECL_VTT_PARM (fn))
{
splay_tree_insert (id.decl_map,
(splay_tree_key) DECL_VTT_PARM (fn),
(splay_tree_value) null_pointer_node);
splay_tree_insert (id.decl_map,
(splay_tree_key) DECL_USE_VTT_PARM (fn),
(splay_tree_value) boolean_false_node);
}
}
/* Map other parameters to their equivalents in the cloned
function. */
else
{
splay_tree_insert (id.decl_map,
(splay_tree_key) parm,
(splay_tree_value) clone_parm);
clone_parm = TREE_CHAIN (clone_parm);
}
}
/* Actually copy the body. */
TREE_CHAIN (DECL_SAVED_TREE (clone)) = copy_body (&id);
/* Clean up. */
splay_tree_delete (id.decl_map);
VARRAY_FREE (id.fns);
/* Now, expand this function into RTL, if appropriate. */
function_name_declared_p = 1;
expand_body (finish_function (0));
pop_from_top_level ();
}
/* We don't need to process the original function any further. */
return 1;
}
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