/* Callgraph based intraprocedural optimizations.
- Copyright (C) 2003 Free Software Foundation, Inc.
+ Copyright (C) 2003, 2004, 2005 Free Software Foundation, Inc.
Contributed by Jan Hubicka
This file is part of GCC.
Software Foundation, 59 Temple Place - Suite 330, Boston, MA
02111-1307, USA. */
+/* This module implements main driver of compilation process as well as
+ few basic intraprocedural optimizers.
+
+ The main scope of this file is to act as an interface in between
+ tree based frontends and the backend (and middle end)
+
+ The front-end is supposed to use following functionality:
+
+ - cgraph_finalize_function
+
+ This function is called once front-end has parsed whole body of function
+ and it is certain that the function body nor the declaration will change.
+
+ (There is one exception needed for implementing GCC extern inline function.)
+
+ - cgraph_varpool_finalize_variable
+
+ This function has same behavior as the above but is used for static
+ variables.
+
+ - cgraph_finalize_compilation_unit
+
+ This function is called once compilation unit is finalized and it will
+ no longer change.
+
+ In the unit-at-a-time the call-graph construction and local function
+ analysis takes place here. Bodies of unreachable functions are released
+ to conserve memory usage.
+
+ ??? The compilation unit in this point of view should be compilation
+ unit as defined by the language - for instance C frontend allows multiple
+ compilation units to be parsed at once and it should call function each
+ time parsing is done so we save memory.
+
+ - cgraph_optimize
+
+ In this unit-at-a-time compilation the intra procedural analysis takes
+ place here. In particular the static functions whose address is never
+ taken are marked as local. Backend can then use this information to
+ modify calling conventions, do better inlining or similar optimizations.
+
+ - cgraph_assemble_pending_functions
+ - cgraph_varpool_assemble_pending_variables
+
+ In non-unit-at-a-time mode these functions can be used to force compilation
+ of functions or variables that are known to be needed at given stage
+ of compilation
+
+ - cgraph_mark_needed_node
+ - cgraph_varpool_mark_needed_node
+
+ When function or variable is referenced by some hidden way (for instance
+ via assembly code and marked by attribute "used"), the call-graph data structure
+ must be updated accordingly by this function.
+
+ - analyze_expr callback
+
+ This function is responsible for lowering tree nodes not understood by
+ generic code into understandable ones or alternatively marking
+ callgraph and varpool nodes referenced by the as needed.
+
+ ??? On the tree-ssa genericizing should take place here and we will avoid
+ need for these hooks (replacing them by genericizing hook)
+
+ - expand_function callback
+
+ This function is used to expand function and pass it into RTL back-end.
+ Front-end should not make any assumptions about when this function can be
+ called. In particular cgraph_assemble_pending_functions,
+ cgraph_varpool_assemble_pending_variables, cgraph_finalize_function,
+ cgraph_varpool_finalize_function, cgraph_optimize can cause arbitrarily
+ previously finalized functions to be expanded.
+
+ We implement two compilation modes.
+
+ - unit-at-a-time: In this mode analyzing of all functions is deferred
+ to cgraph_finalize_compilation_unit and expansion into cgraph_optimize.
+
+ In cgraph_finalize_compilation_unit the reachable functions are
+ analyzed. During analysis the call-graph edges from reachable
+ functions are constructed and their destinations are marked as
+ reachable. References to functions and variables are discovered too
+ and variables found to be needed output to the assembly file. Via
+ mark_referenced call in assemble_variable functions referenced by
+ static variables are noticed too.
+
+ The intra-procedural information is produced and its existence
+ indicated by global_info_ready. Once this flag is set it is impossible
+ to change function from !reachable to reachable and thus
+ assemble_variable no longer call mark_referenced.
+
+ Finally the call-graph is topologically sorted and all reachable functions
+ that has not been completely inlined or are not external are output.
+
+ ??? It is possible that reference to function or variable is optimized
+ out. We can not deal with this nicely because topological order is not
+ suitable for it. For tree-ssa we may consider another pass doing
+ optimization and re-discovering reachable functions.
+
+ ??? Reorganize code so variables are output very last and only if they
+ really has been referenced by produced code, so we catch more cases
+ where reference has been optimized out.
+
+ - non-unit-at-a-time
+
+ All functions are variables are output as early as possible to conserve
+ memory consumption. This may or may not result in less memory used but
+ it is still needed for some legacy code that rely on particular ordering
+ of things output from the compiler.
+
+ Varpool data structures are not used and variables are output directly.
+
+ Functions are output early using call of
+ cgraph_assemble_pending_function from cgraph_finalize_function. The
+ decision on whether function is needed is made more conservative so
+ uninlininable static functions are needed too. During the call-graph
+ construction the edge destinations are not marked as reachable and it
+ is completely relied upn assemble_variable to mark them. */
+
+
#include "config.h"
#include "system.h"
#include "coretypes.h"
#include "tm.h"
#include "tree.h"
+#include "rtl.h"
+#include "tree-flow.h"
#include "tree-inline.h"
#include "langhooks.h"
-#include "hashtab.h"
+#include "pointer-set.h"
#include "toplev.h"
#include "flags.h"
#include "ggc.h"
#include "params.h"
#include "fibheap.h"
#include "c-common.h"
+#include "intl.h"
+#include "function.h"
+#include "tree-gimple.h"
+#include "tree-pass.h"
+#include "output.h"
-#define INSNS_PER_CALL 10
-
-static void cgraph_expand_functions (void);
+static void cgraph_expand_all_functions (void);
static void cgraph_mark_functions_to_output (void);
static void cgraph_expand_function (struct cgraph_node *);
-static tree record_call_1 (tree *, int *, void *);
-static void cgraph_mark_local_functions (void);
-static void cgraph_optimize_function (struct cgraph_node *);
+static tree record_reference (tree *, int *, void *);
+static void cgraph_analyze_function (struct cgraph_node *node);
-/* Statistics we collect about inlining algorithm. */
-static int ncalls_inlined;
-static int nfunctions_inlined;
-static int initial_insns;
-static int overall_insns;
+/* Records tree nodes seen in record_reference. Simply using
+ walk_tree_without_duplicates doesn't guarantee each node is visited
+ once because it gets a new htab upon each recursive call from
+ record_reference itself. */
+static struct pointer_set_t *visited_nodes;
-/* Analyze function once it is parsed. Set up the local information
- available - create cgraph edges for function calls via BODY. */
+static FILE *cgraph_dump_file;
-void
-cgraph_finalize_function (tree decl, tree body ATTRIBUTE_UNUSED)
+/* Determine if function DECL is needed. That is, visible to something
+ either outside this translation unit, something magic in the system
+ configury, or (if not doing unit-at-a-time) to something we havn't
+ seen yet. */
+
+static bool
+decide_is_function_needed (struct cgraph_node *node, tree decl)
{
- struct cgraph_node *node = cgraph_node (decl);
+ tree origin;
+
+ /* If the user told us it is used, then it must be so. */
+ if (lookup_attribute ("used", DECL_ATTRIBUTES (decl)))
+ return true;
+
+ /* ??? If the assembler name is set by hand, it is possible to assemble
+ the name later after finalizing the function and the fact is noticed
+ in assemble_name then. This is arguably a bug. */
+ if (DECL_ASSEMBLER_NAME_SET_P (decl)
+ && TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl)))
+ return true;
+
+ /* If we decided it was needed before, but at the time we didn't have
+ the body of the function available, then it's still needed. We have
+ to go back and re-check its dependencies now. */
+ if (node->needed)
+ return true;
- node->decl = decl;
- node->local.finalized = true;
+ /* Externally visible functions must be output. The exception is
+ COMDAT functions that must be output only when they are needed. */
+ if (TREE_PUBLIC (decl) && !DECL_COMDAT (decl) && !DECL_EXTERNAL (decl))
+ return true;
- /* Function now has DECL_SAVED_TREE set. Enqueue it into cgraph_nodes_queue
- if needed. */
- if (node->needed)
- cgraph_mark_needed_node (node, 0);
- if (/* Externally visible functions must be output. The exception are
- COMDAT functions that must be output only when they are needed.
- Similarly are handled deferred functions and
- external functions (GCC extension "extern inline") */
- (TREE_PUBLIC (decl) && !DECL_COMDAT (decl) && !DECL_EXTERNAL (decl))
- /* ??? Constructors and destructors not called otherwise can be inlined
- into single construction/destruction function per section to save some
- resources. For now just mark it as reachable. */
- || DECL_STATIC_CONSTRUCTOR (decl)
- || DECL_STATIC_DESTRUCTOR (decl)
- /* Function whose name is output to the assembler file must be produced.
- It is possible to assemble the name later after finalizing the function
- and the fact is noticed in assemble_name then. */
- || (DECL_ASSEMBLER_NAME_SET_P (decl)
- && TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl)))
- || lookup_attribute ("used", DECL_ATTRIBUTES (decl)))
- {
- cgraph_mark_needed_node (node, 1);
- }
+ /* Constructors and destructors are reachable from the runtime by
+ some mechanism. */
+ if (DECL_STATIC_CONSTRUCTOR (decl) || DECL_STATIC_DESTRUCTOR (decl))
+ return true;
- (*debug_hooks->deferred_inline_function) (decl);
+ if (flag_unit_at_a_time)
+ return false;
+
+ /* If not doing unit at a time, then we'll only defer this function
+ if its marked for inlining. Otherwise we want to emit it now. */
+
+ /* "extern inline" functions are never output locally. */
+ if (DECL_EXTERNAL (decl))
+ return false;
+ /* Nested functions of extern inline function shall not be emit unless
+ we inlined the origin. */
+ for (origin = decl_function_context (decl); origin;
+ origin = decl_function_context (origin))
+ if (DECL_EXTERNAL (origin))
+ return false;
+ /* We want to emit COMDAT functions only when absolutely necessary. */
+ if (DECL_COMDAT (decl))
+ return false;
+ if (!DECL_INLINE (decl)
+ || (!node->local.disregard_inline_limits
+ /* When declared inline, defer even the uninlinable functions.
+ This allows them to be eliminated when unused. */
+ && !DECL_DECLARED_INLINE_P (decl)
+ && (!node->local.inlinable || !cgraph_default_inline_p (node))))
+ return true;
+
+ return false;
}
-/* Walk tree and record all calls. Called via walk_tree. */
-static tree
-record_call_1 (tree *tp, int *walk_subtrees, void *data)
+/* Walk the decls we marked as necessary and see if they reference new
+ variables or functions and add them into the worklists. */
+static bool
+cgraph_varpool_analyze_pending_decls (void)
{
- if (TREE_CODE (*tp) == VAR_DECL && TREE_STATIC (*tp))
- cgraph_varpool_mark_needed_node (cgraph_varpool_node (*tp));
- /* Record dereferences to the functions. This makes the functions
- reachable unconditionally. */
- else if (TREE_CODE (*tp) == ADDR_EXPR)
- {
- tree decl = TREE_OPERAND (*tp, 0);
- if (TREE_CODE (decl) == FUNCTION_DECL)
- cgraph_mark_needed_node (cgraph_node (decl), 1);
- }
- else if (TREE_CODE (*tp) == CALL_EXPR)
+ bool changed = false;
+ timevar_push (TV_CGRAPH);
+
+ while (cgraph_varpool_first_unanalyzed_node)
{
- tree decl = get_callee_fndecl (*tp);
- if (decl && TREE_CODE (decl) == FUNCTION_DECL)
+ tree decl = cgraph_varpool_first_unanalyzed_node->decl;
+
+ cgraph_varpool_first_unanalyzed_node->analyzed = true;
+
+ cgraph_varpool_first_unanalyzed_node = cgraph_varpool_first_unanalyzed_node->next_needed;
+
+ if (DECL_INITIAL (decl))
{
- if (DECL_BUILT_IN (decl))
- return NULL;
- cgraph_record_call (data, decl);
-
- /* When we see a function call, we don't want to look at the
- function reference in the ADDR_EXPR that is hanging from
- the CALL_EXPR we're examining here, because we would
- conclude incorrectly that the function's address could be
- taken by something that is not a function call. So only
- walk the function parameter list, skip the other subtrees. */
-
- walk_tree (&TREE_OPERAND (*tp, 1), record_call_1, data, NULL);
- *walk_subtrees = 0;
+ visited_nodes = pointer_set_create ();
+ walk_tree (&DECL_INITIAL (decl), record_reference, NULL, visited_nodes);
+ pointer_set_destroy (visited_nodes);
+ visited_nodes = NULL;
}
+ changed = true;
}
- /* Save some cycles by not walking types and declaration as we won't find anything
- usefull there anyway. */
- if (DECL_P (*tp) || TYPE_P (*tp))
- *walk_subtrees = 0;
- return NULL;
+ timevar_pop (TV_CGRAPH);
+ return changed;
}
-/* Create cgraph edges for function calls inside BODY from DECL. */
+/* Optimization of function bodies might've rendered some variables as
+ unnecessary so we want to avoid these from being compiled.
-void
-cgraph_create_edges (tree decl, tree body)
-{
- /* The nodes we're interested in are never shared, so walk
- the tree ignoring duplicates. */
- walk_tree_without_duplicates (&body, record_call_1, decl);
-}
-
-/* Analyze the function scheduled to be output. */
+ This is done by pruning the queue and keeping only the variables that
+ really appear needed (ie they are either externally visible or referenced
+ by compiled function). Re-doing the reachability analysis on variables
+ brings back the remaining variables referenced by these. */
static void
-cgraph_analyze_function (struct cgraph_node *node)
+cgraph_varpool_remove_unreferenced_decls (void)
{
- tree decl = node->decl;
+ struct cgraph_varpool_node *next, *node = cgraph_varpool_nodes_queue;
- if (lang_hooks.callgraph.lower_function)
- (*lang_hooks.callgraph.lower_function) (decl);
+ cgraph_varpool_reset_queue ();
- current_function_decl = node->decl;
+ if (errorcount || sorrycount)
+ return;
- /* First kill forward declaration so reverse inlining works properly. */
- cgraph_create_edges (decl, DECL_SAVED_TREE (decl));
+ while (node)
+ {
+ tree decl = node->decl;
+ next = node->next_needed;
+ node->needed = 0;
- node->local.inlinable = tree_inlinable_function_p (decl);
- if (!DECL_ESTIMATED_INSNS (decl))
- DECL_ESTIMATED_INSNS (decl)
- = (*lang_hooks.tree_inlining.estimate_num_insns) (decl);
- node->local.self_insns = DECL_ESTIMATED_INSNS (decl);
- if (node->local.inlinable)
- node->local.disregard_inline_limits
- = (*lang_hooks.tree_inlining.disregard_inline_limits) (decl);
+ if (node->finalized
+ && ((DECL_ASSEMBLER_NAME_SET_P (decl)
+ && TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl)))
+ || node->force_output
+ || decide_is_variable_needed (node, decl)))
+ cgraph_varpool_mark_needed_node (node);
- /* Inlining characteristics are maintained by the cgraph_mark_inline. */
- node->global.insns = node->local.self_insns;
- if (!DECL_EXTERNAL (node->decl))
- {
- node->global.cloned_times = 1;
- node->global.will_be_output = true;
+ node = next;
}
-
- node->lowered = true;
+ cgraph_varpool_analyze_pending_decls ();
}
-/* Analyze the whole compilation unit once it is parsed completely. */
-void
-cgraph_finalize_compilation_unit (void)
-{
- struct cgraph_node *node;
+/* When not doing unit-at-a-time, output all functions enqueued.
+ Return true when such a functions were found. */
- cgraph_varpool_assemble_pending_decls ();
- if (!quiet_flag)
- fprintf (stderr, "\nAnalyzing compilation unit\n");
+bool
+cgraph_assemble_pending_functions (void)
+{
+ bool output = false;
- timevar_push (TV_CGRAPH);
- if (cgraph_dump_file)
- {
- fprintf (cgraph_dump_file, "\nInitial entry points:");
- for (node = cgraph_nodes; node; node = node->next)
- if (node->needed && DECL_SAVED_TREE (node->decl))
- fprintf (cgraph_dump_file, " %s", cgraph_node_name (node));
- fprintf (cgraph_dump_file, "\n");
- }
+ if (flag_unit_at_a_time)
+ return false;
- /* Propagate reachability flag and lower representation of all reachable
- functions. In the future, lowering will introduce new functions and
- new entry points on the way (by template instantiation and virtual
- method table generation for instance). */
while (cgraph_nodes_queue)
{
- struct cgraph_edge *edge;
- tree decl = cgraph_nodes_queue->decl;
+ struct cgraph_node *n = cgraph_nodes_queue;
- node = cgraph_nodes_queue;
cgraph_nodes_queue = cgraph_nodes_queue->next_needed;
+ n->next_needed = NULL;
+ if (!n->global.inlined_to
+ && !n->alias
+ && !DECL_EXTERNAL (n->decl))
+ {
+ cgraph_expand_function (n);
+ output = true;
+ }
+ }
- if (node->lowered || !node->reachable || !DECL_SAVED_TREE (decl))
- abort ();
+ return output;
+}
+/* As an GCC extension we allow redefinition of the function. The
+ semantics when both copies of bodies differ is not well defined.
+ We replace the old body with new body so in unit at a time mode
+ we always use new body, while in normal mode we may end up with
+ old body inlined into some functions and new body expanded and
+ inlined in others.
- cgraph_analyze_function (node);
- for (edge = node->callees; edge; edge = edge->next_callee)
- {
- if (!edge->callee->reachable)
- cgraph_mark_needed_node (edge->callee, 0);
- }
- cgraph_varpool_assemble_pending_decls ();
- }
- /* Collect entry points to the unit. */
+ ??? It may make more sense to use one body for inlining and other
+ body for expanding the function but this is difficult to do. */
- if (cgraph_dump_file)
+static void
+cgraph_reset_node (struct cgraph_node *node)
+{
+ /* If node->output is set, then this is a unit-at-a-time compilation
+ and we have already begun whole-unit analysis. This is *not*
+ testing for whether we've already emitted the function. That
+ case can be sort-of legitimately seen with real function
+ redefinition errors. I would argue that the front end should
+ never present us with such a case, but don't enforce that for now. */
+ gcc_assert (!node->output);
+
+ /* Reset our data structures so we can analyze the function again. */
+ memset (&node->local, 0, sizeof (node->local));
+ memset (&node->global, 0, sizeof (node->global));
+ memset (&node->rtl, 0, sizeof (node->rtl));
+ node->analyzed = false;
+ node->local.redefined_extern_inline = true;
+ node->local.finalized = false;
+
+ if (!flag_unit_at_a_time)
{
- fprintf (cgraph_dump_file, "\nUnit entry points:");
- for (node = cgraph_nodes; node; node = node->next)
- if (node->needed && DECL_SAVED_TREE (node->decl))
- fprintf (cgraph_dump_file, " %s", cgraph_node_name (node));
- fprintf (cgraph_dump_file, "\n");
- dump_cgraph (cgraph_dump_file);
+ struct cgraph_node *n;
+
+ for (n = cgraph_nodes; n; n = n->next)
+ if (n->global.inlined_to == node)
+ cgraph_remove_node (n);
}
- if (cgraph_dump_file)
- fprintf (cgraph_dump_file, "\nReclaiming functions:");
+ cgraph_node_remove_callees (node);
- for (node = cgraph_nodes; node; node = node->next)
+ /* We may need to re-queue the node for assembling in case
+ we already proceeded it and ignored as not needed. */
+ if (node->reachable && !flag_unit_at_a_time)
{
- tree decl = node->decl;
+ struct cgraph_node *n;
- if (!node->reachable && DECL_SAVED_TREE (decl))
- {
- cgraph_remove_node (node);
- if (cgraph_dump_file)
- fprintf (cgraph_dump_file, " %s", cgraph_node_name (node));
- }
+ for (n = cgraph_nodes_queue; n; n = n->next_needed)
+ if (n == node)
+ break;
+ if (!n)
+ node->reachable = 0;
}
- if (cgraph_dump_file)
- fprintf (cgraph_dump_file, "\n");
- ggc_collect ();
- timevar_pop (TV_CGRAPH);
}
-/* Figure out what functions we want to assemble. */
+/* DECL has been parsed. Take it, queue it, compile it at the whim of the
+ logic in effect. If NESTED is true, then our caller cannot stand to have
+ the garbage collector run at the moment. We would need to either create
+ a new GC context, or just not compile right now. */
-static void
-cgraph_mark_functions_to_output (void)
+void
+cgraph_finalize_function (tree decl, bool nested)
{
- struct cgraph_node *node;
+ struct cgraph_node *node = cgraph_node (decl);
- for (node = cgraph_nodes; node; node = node->next)
- {
- tree decl = node->decl;
- struct cgraph_edge *e;
- if (node->output)
- abort ();
+ if (node->local.finalized)
+ cgraph_reset_node (node);
- for (e = node->callers; e; e = e->next_caller)
- if (!e->inline_call)
- break;
+ notice_global_symbol (decl);
+ node->decl = decl;
+ node->local.finalized = true;
+ node->lowered = DECL_STRUCT_FUNCTION (decl)->cfg != NULL;
+ if (node->nested)
+ lower_nested_functions (decl);
+ gcc_assert (!node->nested);
- /* We need to output all local functions that are used and not
- always inlined, as well as those that are reachable from
- outside the current compilation unit. */
- if (DECL_SAVED_TREE (decl)
- && (node->needed
- || (e && node->reachable))
- && !TREE_ASM_WRITTEN (decl) && !node->origin
- && !DECL_EXTERNAL (decl))
- node->output = 1;
+ /* If not unit at a time, then we need to create the call graph
+ now, so that called functions can be queued and emitted now. */
+ if (!flag_unit_at_a_time)
+ {
+ cgraph_analyze_function (node);
+ cgraph_decide_inlining_incrementally (node);
}
-}
-/* Optimize the function before expansion. */
+ if (decide_is_function_needed (node, decl))
+ cgraph_mark_needed_node (node);
-static void
-cgraph_optimize_function (struct cgraph_node *node)
-{
- tree decl = node->decl;
+ /* Since we reclaim unreachable nodes at the end of every language
+ level unit, we need to be conservative about possible entry points
+ there. */
+ if (TREE_PUBLIC (decl) && !DECL_COMDAT (decl) && !DECL_EXTERNAL (decl))
+ cgraph_mark_reachable_node (node);
- timevar_push (TV_INTEGRATION);
- /* optimize_inline_calls avoids inlining of current_function_decl. */
- current_function_decl = 0;
- if (flag_inline_trees)
- optimize_inline_calls (decl);
- if (node->nested)
+ /* If not unit at a time, go ahead and emit everything we've found
+ to be reachable at this time. */
+ if (!nested)
{
- for (node = node->nested; node; node = node->next_nested)
- cgraph_optimize_function (node);
+ if (!cgraph_assemble_pending_functions ())
+ ggc_collect ();
}
- timevar_pop (TV_INTEGRATION);
+
+ /* If we've not yet emitted decl, tell the debug info about it. */
+ if (!TREE_ASM_WRITTEN (decl))
+ (*debug_hooks->deferred_inline_function) (decl);
+
+ /* Possibly warn about unused parameters. */
+ if (warn_unused_parameter)
+ do_warn_unused_parameter (decl);
}
-/* Expand function specified by NODE. */
+void
+cgraph_lower_function (struct cgraph_node *node)
+{
+ if (node->lowered)
+ return;
+ tree_lowering_passes (node->decl);
+ node->lowered = true;
+}
-static void
-cgraph_expand_function (struct cgraph_node *node)
+/* Walk tree and record all calls. Called via walk_tree. */
+static tree
+record_reference (tree *tp, int *walk_subtrees, void *data)
{
- tree decl = node->decl;
- struct cgraph_edge *e;
+ tree t = *tp;
- announce_function (decl);
+ switch (TREE_CODE (t))
+ {
+ case VAR_DECL:
+ /* ??? Really, we should mark this decl as *potentially* referenced
+ by this function and re-examine whether the decl is actually used
+ after rtl has been generated. */
+ if (TREE_STATIC (t) || DECL_EXTERNAL (t))
+ {
+ cgraph_varpool_mark_needed_node (cgraph_varpool_node (t));
+ if (lang_hooks.callgraph.analyze_expr)
+ return lang_hooks.callgraph.analyze_expr (tp, walk_subtrees,
+ data);
+ }
+ break;
- cgraph_optimize_function (node);
+ case FDESC_EXPR:
+ case ADDR_EXPR:
+ if (flag_unit_at_a_time)
+ {
+ /* Record dereferences to the functions. This makes the
+ functions reachable unconditionally. */
+ tree decl = TREE_OPERAND (*tp, 0);
+ if (TREE_CODE (decl) == FUNCTION_DECL)
+ cgraph_mark_needed_node (cgraph_node (decl));
+ }
+ break;
- /* Generate RTL for the body of DECL. Nested functions are expanded
- via lang_expand_decl_stmt. */
- (*lang_hooks.callgraph.expand_function) (decl);
+ default:
+ /* Save some cycles by not walking types and declaration as we
+ won't find anything useful there anyway. */
+ if (IS_TYPE_OR_DECL_P (*tp))
+ {
+ *walk_subtrees = 0;
+ break;
+ }
- for (e = node->callers; e; e = e->next_caller)
- if (e->inline_call)
+ if ((unsigned int) TREE_CODE (t) >= LAST_AND_UNUSED_TREE_CODE)
+ return lang_hooks.callgraph.analyze_expr (tp, walk_subtrees, data);
break;
- if (!e)
- DECL_SAVED_TREE (decl) = NULL;
- current_function_decl = NULL;
+ }
+
+ return NULL;
}
-/* Fill array order with all nodes with output flag set in the reverse
- topological order. */
-static int
-cgraph_postorder (struct cgraph_node **order)
+/* Create cgraph edges for function calls inside BODY from NODE. */
+
+static void
+cgraph_create_edges (struct cgraph_node *node, tree body)
{
- struct cgraph_node *node, *node2;
- int stack_size = 0;
- int order_pos = 0;
- struct cgraph_edge *edge, last;
+ basic_block bb;
- struct cgraph_node **stack =
- xcalloc (cgraph_n_nodes, sizeof (struct cgraph_node *));
+ struct function *this_cfun = DECL_STRUCT_FUNCTION (body);
+ block_stmt_iterator bsi;
+ tree step;
+ visited_nodes = pointer_set_create ();
- /* We have to deal with cycles nicely, so use a depth first traversal
- output algorithm. Ignore the fact that some functions won't need
- to be output and put them into order as well, so we get dependencies
- right through intline functions. */
- for (node = cgraph_nodes; node; node = node->next)
- node->aux = NULL;
- for (node = cgraph_nodes; node; node = node->next)
- if (!node->aux)
+ /* Reach the trees by walking over the CFG, and note the
+ enclosing basic-blocks in the call edges. */
+ FOR_EACH_BB_FN (bb, this_cfun)
+ for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi))
{
- node2 = node;
- if (!node->callers)
- node->aux = &last;
- else
- node->aux = node->callers;
- while (node2)
+ tree stmt = bsi_stmt (bsi);
+ tree call = get_call_expr_in (stmt);
+ tree decl;
+
+ if (call && (decl = get_callee_fndecl (call)))
{
- while (node2->aux != &last)
- {
- edge = node2->aux;
- if (edge->next_caller)
- node2->aux = edge->next_caller;
- else
- node2->aux = &last;
- if (!edge->caller->aux)
- {
- if (!edge->caller->callers)
- edge->caller->aux = &last;
- else
- edge->caller->aux = edge->caller->callers;
- stack[stack_size++] = node2;
- node2 = edge->caller;
- break;
- }
- }
- if (node2->aux == &last)
- {
- order[order_pos++] = node2;
- if (stack_size)
- node2 = stack[--stack_size];
- else
- node2 = NULL;
- }
+ cgraph_create_edge (node, cgraph_node (decl), stmt,
+ bb->count,
+ bb->loop_depth);
+ walk_tree (&TREE_OPERAND (call, 1),
+ record_reference, node, visited_nodes);
+ if (TREE_CODE (stmt) == MODIFY_EXPR)
+ walk_tree (&TREE_OPERAND (stmt, 0),
+ record_reference, node, visited_nodes);
}
+ else
+ walk_tree (bsi_stmt_ptr (bsi), record_reference, node, visited_nodes);
}
- free (stack);
- return order_pos;
-}
-
-#define INLINED_TIMES(node) ((size_t)(node)->aux)
-#define SET_INLINED_TIMES(node,times) ((node)->aux = (void *)(times))
-/* Return list of nodes we decided to inline NODE into, set their output
- flag and compute INLINED_TIMES.
+ /* Look for initializers of constant variables and private statics. */
+ for (step = DECL_STRUCT_FUNCTION (body)->unexpanded_var_list;
+ step;
+ step = TREE_CHAIN (step))
+ {
+ tree decl = TREE_VALUE (step);
+ if (TREE_CODE (decl) == VAR_DECL
+ && (TREE_STATIC (decl) && !DECL_EXTERNAL (decl))
+ && flag_unit_at_a_time)
+ cgraph_varpool_finalize_decl (decl);
+ else if (TREE_CODE (decl) == VAR_DECL && DECL_INITIAL (decl))
+ walk_tree (&DECL_INITIAL (decl), record_reference, node, visited_nodes);
+ }
+
+ pointer_set_destroy (visited_nodes);
+ visited_nodes = NULL;
+}
- We do simple backtracing to get INLINED_TIMES right. This should not be
- expensive as we limit the amount of inlining. Alternatively we may first
- discover set of nodes, topologically sort these and propagate
- INLINED_TIMES */
-static int
-cgraph_inlined_into (struct cgraph_node *node, struct cgraph_node **array)
+/* Verify cgraph nodes of given cgraph node. */
+void
+verify_cgraph_node (struct cgraph_node *node)
{
- int nfound = 0;
- struct cgraph_edge **stack;
- struct cgraph_edge *e, *e1;
- int sp;
- int i;
+ struct cgraph_edge *e;
+ struct cgraph_node *main_clone;
+ struct function *this_cfun = DECL_STRUCT_FUNCTION (node->decl);
+ basic_block this_block;
+ block_stmt_iterator bsi;
+ bool error_found = false;
- /* Fast path: since we traverse in mostly topological order, we will likely
- find no edges. */
+ timevar_push (TV_CGRAPH_VERIFY);
+ for (e = node->callees; e; e = e->next_callee)
+ if (e->aux)
+ {
+ error ("Aux field set for edge %s->%s",
+ cgraph_node_name (e->caller), cgraph_node_name (e->callee));
+ error_found = true;
+ }
for (e = node->callers; e; e = e->next_caller)
- if (e->inline_call)
- break;
-
- if (!e)
- return 0;
-
- /* Allocate stack for back-tracking up callgraph. */
- stack = xmalloc ((cgraph_n_nodes + 1) * sizeof (struct cgraph_edge));
- sp = 0;
-
- /* Push the first edge on to the stack. */
- stack[sp++] = e;
-
- while (sp)
{
- struct cgraph_node *caller;
-
- /* Look at the edge on the top of the stack. */
- e = stack[sp - 1];
- caller = e->caller;
-
- /* Check if the caller destination has been visited yet. */
- if (!caller->output)
+ if (!e->inline_failed)
{
- array[nfound++] = e->caller;
- /* Mark that we have visited the destination. */
- caller->output = true;
- SET_INLINED_TIMES (caller, 0);
- }
- SET_INLINED_TIMES (caller, INLINED_TIMES (caller) + 1);
-
- for (e1 = caller->callers; e1; e1 = e1->next_caller)
- if (e1->inline_call)
- break;
- if (e1)
- stack[sp++] = e1;
- else
- {
- while (true)
+ if (node->global.inlined_to
+ != (e->caller->global.inlined_to
+ ? e->caller->global.inlined_to : e->caller))
{
- for (e1 = e->next_caller; e1; e1 = e1->next_caller)
- if (e1->inline_call)
- break;
-
- if (e1)
- {
- stack[sp - 1] = e1;
- break;
- }
- else
- {
- sp--;
- if (!sp)
- break;
- e = stack[sp - 1];
- }
+ error ("Inlined_to pointer is wrong");
+ error_found = true;
+ }
+ if (node->callers->next_caller)
+ {
+ error ("Multiple inline callers");
+ error_found = true;
}
}
+ else
+ if (node->global.inlined_to)
+ {
+ error ("Inlined_to pointer set for noninline callers");
+ error_found = true;
+ }
}
-
- free (stack);
-
-
- if (cgraph_dump_file)
+ if (!node->callers && node->global.inlined_to)
{
- fprintf (cgraph_dump_file, "Found inline predecesors of %s:",
- cgraph_node_name (node));
- for (i = 0; i < nfound; i++)
- {
- fprintf (cgraph_dump_file, " %s", cgraph_node_name (array[i]));
- if (INLINED_TIMES (array[i]) != 1)
- fprintf (cgraph_dump_file, " (%i times)",
- (int)INLINED_TIMES (array[i]));
- }
- fprintf (cgraph_dump_file, "\n");
+ error ("Inlined_to pointer is set but no predecesors found");
+ error_found = true;
+ }
+ if (node->global.inlined_to == node)
+ {
+ error ("Inlined_to pointer refers to itself");
+ error_found = true;
}
- return nfound;
-}
-
-/* Return list of nodes we decided to inline into NODE, set their output
- flag and compute INLINED_TIMES.
-
- This function is identical to cgraph_inlined_into with callers and callees
- nodes swapped. */
-
-static int
-cgraph_inlined_callees (struct cgraph_node *node, struct cgraph_node **array)
-{
- int nfound = 0;
- struct cgraph_edge **stack;
- struct cgraph_edge *e, *e1;
- int sp;
- int i;
-
- /* Fast path: since we traverse in mostly topological order, we will likely
- find no edges. */
- for (e = node->callees; e; e = e->next_callee)
- if (e->inline_call)
+ for (main_clone = cgraph_node (node->decl); main_clone;
+ main_clone = main_clone->next_clone)
+ if (main_clone == node)
break;
-
- if (!e)
- return 0;
-
- /* Allocate stack for back-tracking up callgraph. */
- stack = xmalloc ((cgraph_n_nodes + 1) * sizeof (struct cgraph_edge));
- sp = 0;
-
- /* Push the first edge on to the stack. */
- stack[sp++] = e;
-
- while (sp)
+ if (!node)
{
- struct cgraph_node *callee;
-
- /* Look at the edge on the top of the stack. */
- e = stack[sp - 1];
- callee = e->callee;
-
- /* Check if the callee destination has been visited yet. */
- if (!callee->output)
+ error ("Node not found in DECL_ASSEMBLER_NAME hash");
+ error_found = true;
+ }
+
+ if (node->analyzed
+ && DECL_SAVED_TREE (node->decl) && !TREE_ASM_WRITTEN (node->decl)
+ && (!DECL_EXTERNAL (node->decl) || node->global.inlined_to))
+ {
+ if (this_cfun->cfg)
{
- array[nfound++] = e->callee;
- /* Mark that we have visited the destination. */
- callee->output = true;
- SET_INLINED_TIMES (callee, 0);
+ /* The nodes we're interested in are never shared, so walk
+ the tree ignoring duplicates. */
+ visited_nodes = pointer_set_create ();
+ /* Reach the trees by walking over the CFG, and note the
+ enclosing basic-blocks in the call edges. */
+ FOR_EACH_BB_FN (this_block, this_cfun)
+ for (bsi = bsi_start (this_block); !bsi_end_p (bsi); bsi_next (&bsi))
+ {
+ tree stmt = bsi_stmt (bsi);
+ tree call = get_call_expr_in (stmt);
+ tree decl;
+ if (call && (decl = get_callee_fndecl (call)))
+ {
+ struct cgraph_edge *e = cgraph_edge (node, stmt);
+ if (e)
+ {
+ if (e->aux)
+ {
+ error ("Shared call_stmt:");
+ debug_generic_stmt (stmt);
+ error_found = true;
+ }
+ if (e->callee->decl != cgraph_node (decl)->decl)
+ {
+ error ("Edge points to wrong declaration:");
+ debug_tree (e->callee->decl);
+ fprintf (stderr," Instead of:");
+ debug_tree (decl);
+ }
+ e->aux = (void *)1;
+ }
+ else
+ {
+ error ("Missing callgraph edge for call stmt:");
+ debug_generic_stmt (stmt);
+ error_found = true;
+ }
+ }
+ }
+ pointer_set_destroy (visited_nodes);
+ visited_nodes = NULL;
}
- SET_INLINED_TIMES (callee, INLINED_TIMES (callee) + 1);
-
- for (e1 = callee->callees; e1; e1 = e1->next_callee)
- if (e1->inline_call)
- break;
- if (e1)
- stack[sp++] = e1;
else
+ /* No CFG available?! */
+ gcc_unreachable ();
+
+ for (e = node->callees; e; e = e->next_callee)
{
- while (true)
+ if (!e->aux)
{
- for (e1 = e->next_callee; e1; e1 = e1->next_callee)
- if (e1->inline_call)
- break;
-
- if (e1)
- {
- stack[sp - 1] = e1;
- break;
- }
- else
- {
- sp--;
- if (!sp)
- break;
- e = stack[sp - 1];
- }
+ error ("Edge %s->%s has no corresponding call_stmt",
+ cgraph_node_name (e->caller),
+ cgraph_node_name (e->callee));
+ debug_generic_stmt (e->call_stmt);
+ error_found = true;
}
+ e->aux = 0;
}
}
+ if (error_found)
+ {
+ dump_cgraph_node (stderr, node);
+ internal_error ("verify_cgraph_node failed.");
+ }
+ timevar_pop (TV_CGRAPH_VERIFY);
+}
+
+/* Verify whole cgraph structure. */
+void
+verify_cgraph (void)
+{
+ struct cgraph_node *node;
+
+ if (sorrycount || errorcount)
+ return;
+
+ for (node = cgraph_nodes; node; node = node->next)
+ verify_cgraph_node (node);
+}
+
+
+/* Output all variables enqueued to be assembled. */
+bool
+cgraph_varpool_assemble_pending_decls (void)
+{
+ bool changed = false;
- free (stack);
+ if (errorcount || sorrycount)
+ return false;
+
+ /* EH might mark decls as needed during expansion. This should be safe since
+ we don't create references to new function, but it should not be used
+ elsewhere. */
+ cgraph_varpool_analyze_pending_decls ();
- if (cgraph_dump_file)
+ while (cgraph_varpool_nodes_queue)
{
- fprintf (cgraph_dump_file, "Found inline successors of %s:",
- cgraph_node_name (node));
- for (i = 0; i < nfound; i++)
+ tree decl = cgraph_varpool_nodes_queue->decl;
+ struct cgraph_varpool_node *node = cgraph_varpool_nodes_queue;
+
+ cgraph_varpool_nodes_queue = cgraph_varpool_nodes_queue->next_needed;
+ if (!TREE_ASM_WRITTEN (decl) && !node->alias && !DECL_EXTERNAL (decl))
{
- fprintf (cgraph_dump_file, " %s", cgraph_node_name (array[i]));
- if (INLINED_TIMES (array[i]) != 1)
- fprintf (cgraph_dump_file, " (%i times)",
- (int)INLINED_TIMES (array[i]));
+ assemble_variable (decl, 0, 1, 0);
+ /* Local static variables are never seen by check_global_declarations
+ so we need to output debug info by hand. */
+ if (decl_function_context (decl) && errorcount == 0 && sorrycount == 0)
+ {
+ timevar_push (TV_SYMOUT);
+ (*debug_hooks->global_decl) (decl);
+ timevar_pop (TV_SYMOUT);
+ }
+ changed = true;
}
- fprintf (cgraph_dump_file, "\n");
+ node->next_needed = NULL;
}
-
- return nfound;
-}
-
-/* Estimate size of the function after inlining WHAT into TO. */
-
-static int
-cgraph_estimate_size_after_inlining (int times, struct cgraph_node *to,
- struct cgraph_node *what)
-{
- return (what->global.insns - INSNS_PER_CALL) *times + to->global.insns;
+ return changed;
}
-/* Estimate the growth caused by inlining NODE into all callees. */
-
-static int
-cgraph_estimate_growth (struct cgraph_node *node)
+/* Analyze the function scheduled to be output. */
+static void
+cgraph_analyze_function (struct cgraph_node *node)
{
- int growth = 0;
- int calls_saved = 0;
- int clones_added = 0;
+ tree decl = node->decl;
struct cgraph_edge *e;
- for (e = node->callers; e; e = e->next_caller)
- if (!e->inline_call)
- {
- growth += ((cgraph_estimate_size_after_inlining (1, e->caller, node)
- -
- e->caller->global.insns) *e->caller->global.cloned_times);
- calls_saved += e->caller->global.cloned_times;
- clones_added += e->caller->global.cloned_times;
- }
+ current_function_decl = decl;
+ push_cfun (DECL_STRUCT_FUNCTION (decl));
+ cgraph_lower_function (node);
- /* ??? Wrong for self recursive functions or cases where we decide to not
- inline for different reasons, but it is not big deal as in that case
- we will keep the body around, but we will also avoid some inlining. */
- if (!node->needed && !node->origin && !DECL_EXTERNAL (node->decl))
- growth -= node->global.insns, clones_added--;
+ /* First kill forward declaration so reverse inlining works properly. */
+ cgraph_create_edges (node, decl);
- if (!calls_saved)
- calls_saved = 1;
+ node->local.inlinable = tree_inlinable_function_p (decl);
+ node->local.self_insns = estimate_num_insns (decl);
+ if (node->local.inlinable)
+ node->local.disregard_inline_limits
+ = lang_hooks.tree_inlining.disregard_inline_limits (decl);
+ for (e = node->callers; e; e = e->next_caller)
+ {
+ if (node->local.redefined_extern_inline)
+ e->inline_failed = N_("redefined extern inline functions are not "
+ "considered for inlining");
+ else if (!node->local.inlinable)
+ e->inline_failed = N_("function not inlinable");
+ else
+ e->inline_failed = N_("function not considered for inlining");
+ }
+ if (flag_really_no_inline && !node->local.disregard_inline_limits)
+ node->local.inlinable = 0;
+ /* Inlining characteristics are maintained by the cgraph_mark_inline. */
+ node->global.insns = node->local.self_insns;
- return growth;
+ node->analyzed = true;
+ pop_cfun ();
+ current_function_decl = NULL;
}
-/* Update insn sizes after inlining WHAT into TO that is already inlined into
- all nodes in INLINED array. */
+/* Analyze the whole compilation unit once it is parsed completely. */
-static void
-cgraph_mark_inline (struct cgraph_node *to, struct cgraph_node *what,
- struct cgraph_node **inlined, int ninlined,
- struct cgraph_node **inlined_callees,
- int ninlined_callees)
+void
+cgraph_finalize_compilation_unit (void)
{
- int i;
- int times = 0;
- int clones = 0;
- struct cgraph_edge *e;
- bool called = false;
- int new_insns;
+ struct cgraph_node *node;
+ /* Keep track of already processed nodes when called multiple times for
+ intermodule optimization. */
+ static struct cgraph_node *first_analyzed;
+
+ finish_aliases_1 ();
- for (e = what->callers; e; e = e->next_caller)
+ if (!flag_unit_at_a_time)
{
- if (e->caller == to)
- {
- if (e->inline_call)
- abort ();
- e->inline_call = true;
- times++;
- clones += e->caller->global.cloned_times;
- }
- else if (!e->inline_call)
- called = true;
+ cgraph_assemble_pending_functions ();
+ return;
}
- if (!times)
- abort ();
- ncalls_inlined += times;
- new_insns = cgraph_estimate_size_after_inlining (times, to, what);
- if (to->global.will_be_output)
- overall_insns += new_insns - to->global.insns;
- to->global.insns = new_insns;
-
- if (!called && !what->needed && !what->origin
- && !DECL_EXTERNAL (what->decl))
+ if (!quiet_flag)
{
- if (!what->global.will_be_output)
- abort ();
- clones--;
- nfunctions_inlined++;
- what->global.will_be_output = 0;
- overall_insns -= what->global.insns;
+ fprintf (stderr, "\nAnalyzing compilation unit");
+ fflush (stderr);
}
- what->global.cloned_times += clones;
- for (i = 0; i < ninlined; i++)
+
+ timevar_push (TV_CGRAPH);
+ cgraph_varpool_analyze_pending_decls ();
+ if (cgraph_dump_file)
{
- new_insns =
- cgraph_estimate_size_after_inlining (INLINED_TIMES (inlined[i]) *
- times, inlined[i], what);
- if (inlined[i]->global.will_be_output)
- overall_insns += new_insns - inlined[i]->global.insns;
- inlined[i]->global.insns = new_insns;
+ fprintf (cgraph_dump_file, "Initial entry points:");
+ for (node = cgraph_nodes; node != first_analyzed; node = node->next)
+ if (node->needed && DECL_SAVED_TREE (node->decl))
+ fprintf (cgraph_dump_file, " %s", cgraph_node_name (node));
+ fprintf (cgraph_dump_file, "\n");
}
- for (i = 0; i < ninlined_callees; i++)
+
+ /* Propagate reachability flag and lower representation of all reachable
+ functions. In the future, lowering will introduce new functions and
+ new entry points on the way (by template instantiation and virtual
+ method table generation for instance). */
+ while (cgraph_nodes_queue)
{
- inlined_callees[i]->global.cloned_times +=
- INLINED_TIMES (inlined_callees[i]) * clones;
- }
-}
+ struct cgraph_edge *edge;
+ tree decl = cgraph_nodes_queue->decl;
-/* Return false when inlining WHAT into TO is not good idea as it would cause
- too large growth of function bodies. */
+ node = cgraph_nodes_queue;
+ cgraph_nodes_queue = cgraph_nodes_queue->next_needed;
+ node->next_needed = NULL;
-static bool
-cgraph_check_inline_limits (struct cgraph_node *to, struct cgraph_node *what,
- struct cgraph_node **inlined, int ninlined)
-{
- int i;
- int times = 0;
- struct cgraph_edge *e;
- int newsize;
- int limit;
+ /* ??? It is possible to create extern inline function and later using
+ weak alias attribute to kill its body. See
+ gcc.c-torture/compile/20011119-1.c */
+ if (!DECL_SAVED_TREE (decl))
+ {
+ cgraph_reset_node (node);
+ continue;
+ }
- for (e = to->callees; e; e = e->next_callee)
- if (e->callee == what)
- times++;
+ gcc_assert (!node->analyzed && node->reachable);
+ gcc_assert (DECL_SAVED_TREE (decl));
- /* When inlining large function body called once into small function,
- take the inlined function as base for limiting the growth. */
- if (to->local.self_insns > what->local.self_insns)
- limit = to->local.self_insns;
- else
- limit = what->local.self_insns;
+ cgraph_analyze_function (node);
+
+ for (edge = node->callees; edge; edge = edge->next_callee)
+ if (!edge->callee->reachable)
+ cgraph_mark_reachable_node (edge->callee);
- limit += limit * PARAM_VALUE (PARAM_LARGE_FUNCTION_GROWTH) / 100;
+ cgraph_varpool_analyze_pending_decls ();
+ }
- newsize = cgraph_estimate_size_after_inlining (times, to, what);
- if (newsize > PARAM_VALUE (PARAM_LARGE_FUNCTION_INSNS)
- && newsize > limit)
- return false;
- for (i = 0; i < ninlined; i++)
+ /* Collect entry points to the unit. */
+
+ if (cgraph_dump_file)
{
- newsize =
- cgraph_estimate_size_after_inlining (INLINED_TIMES (inlined[i]) *
- times, inlined[i], what);
- if (newsize > PARAM_VALUE (PARAM_LARGE_FUNCTION_INSNS)
- && newsize >
- inlined[i]->local.self_insns *
- (100 + PARAM_VALUE (PARAM_LARGE_FUNCTION_GROWTH)) / 100)
- return false;
+ fprintf (cgraph_dump_file, "Unit entry points:");
+ for (node = cgraph_nodes; node != first_analyzed; node = node->next)
+ if (node->needed && DECL_SAVED_TREE (node->decl))
+ fprintf (cgraph_dump_file, " %s", cgraph_node_name (node));
+ fprintf (cgraph_dump_file, "\n\nInitial ");
+ dump_cgraph (cgraph_dump_file);
}
- return true;
-}
-/* Return true when function N is small enought to be inlined. */
+ if (cgraph_dump_file)
+ fprintf (cgraph_dump_file, "\nReclaiming functions:");
-static bool
-cgraph_default_inline_p (struct cgraph_node *n)
-{
- if (!DECL_INLINE (n->decl) || !DECL_SAVED_TREE (n->decl))
- return false;
- if (DECL_DECLARED_INLINE_P (n->decl))
- return n->global.insns < MAX_INLINE_INSNS_SINGLE;
- else
- return n->global.insns < MAX_INLINE_INSNS_AUTO;
-}
+ for (node = cgraph_nodes; node != first_analyzed; node = node->next)
+ {
+ tree decl = node->decl;
-/* We use greedy algorithm for inlining of small functions:
- All inline candidates are put into prioritized heap based on estimated
- growth of the overall number of instructions and then update the estimates.
+ if (node->local.finalized && !DECL_SAVED_TREE (decl))
+ cgraph_reset_node (node);
- INLINED and INLINED_CALEES are just pointers to arrays large enought
- to be passed to cgraph_inlined_into and cgraph_inlined_callees. */
+ if (!node->reachable && DECL_SAVED_TREE (decl))
+ {
+ if (cgraph_dump_file)
+ fprintf (cgraph_dump_file, " %s", cgraph_node_name (node));
+ cgraph_remove_node (node);
+ continue;
+ }
+ else
+ node->next_needed = NULL;
+ gcc_assert (!node->local.finalized || DECL_SAVED_TREE (decl));
+ gcc_assert (node->analyzed == node->local.finalized);
+ }
+ if (cgraph_dump_file)
+ {
+ fprintf (cgraph_dump_file, "\n\nReclaimed ");
+ dump_cgraph (cgraph_dump_file);
+ }
+ first_analyzed = cgraph_nodes;
+ ggc_collect ();
+ timevar_pop (TV_CGRAPH);
+}
+/* Figure out what functions we want to assemble. */
static void
-cgraph_decide_inlining_of_small_functions (struct cgraph_node **inlined,
- struct cgraph_node **inlined_callees)
+cgraph_mark_functions_to_output (void)
{
- int i;
struct cgraph_node *node;
- fibheap_t heap = fibheap_new ();
- struct fibnode **heap_node =
- xcalloc (cgraph_max_uid, sizeof (struct fibnode *));
- int ninlined, ninlined_callees;
- int max_insns = ((HOST_WIDEST_INT) initial_insns
- * (100 + PARAM_VALUE (PARAM_INLINE_UNIT_GROWTH)) / 100);
-
- /* Put all inline candidates into the heap. */
for (node = cgraph_nodes; node; node = node->next)
{
+ tree decl = node->decl;
struct cgraph_edge *e;
+
+ gcc_assert (!node->output);
- if (!node->local.inlinable || !node->callers
- || !cgraph_default_inline_p (node))
- continue;
-
- /* Rule out always_inline functions we dealt with earlier. */
for (e = node->callers; e; e = e->next_caller)
- if (e->inline_call)
+ if (e->inline_failed)
break;
- if (e)
- continue;
- heap_node[node->uid] =
- fibheap_insert (heap, cgraph_estimate_growth (node), node);
- }
-
- if (cgraph_dump_file)
- fprintf (cgraph_dump_file, "\n\nDeciding on inlining: ");
- while ((node = fibheap_extract_min (heap)) && overall_insns <= max_insns)
- {
- struct cgraph_edge *e;
- int old_insns = overall_insns;
-
- heap_node[node->uid] = NULL;
- if (cgraph_dump_file)
- fprintf (cgraph_dump_file, "Considering %s %i insns, growth %i.\n",
- cgraph_node_name (node), node->global.insns,
- cgraph_estimate_growth (node));
- if (!cgraph_default_inline_p (node))
- {
- if (cgraph_dump_file)
- fprintf (cgraph_dump_file, "Function too large.\n");
- continue;
- }
- ninlined_callees = cgraph_inlined_callees (node, inlined_callees);
- for (e = node->callers; e; e = e->next_caller)
- if (!e->inline_call && e->caller != node)
- {
- ninlined = cgraph_inlined_into (e->caller, inlined);
- if (e->callee->output
- || !cgraph_check_inline_limits (e->caller, node, inlined,
- ninlined))
- {
- for (i = 0; i < ninlined; i++)
- inlined[i]->output = 0, node->aux = 0;
- if (cgraph_dump_file)
- fprintf (cgraph_dump_file, "Not inlining into %s\n",
- cgraph_node_name (e->caller));
- continue;
- }
- cgraph_mark_inline (e->caller, node, inlined, ninlined,
- inlined_callees, ninlined_callees);
- if (heap_node[e->caller->uid])
- fibheap_replace_key (heap, heap_node[e->caller->uid],
- cgraph_estimate_growth (e->caller));
-
- /* Size of the functions we updated into has changed, so update
- the keys. */
- for (i = 0; i < ninlined; i++)
- {
- inlined[i]->output = 0, node->aux = 0;
- if (heap_node[inlined[i]->uid])
- fibheap_replace_key (heap, heap_node[inlined[i]->uid],
- cgraph_estimate_growth (inlined[i]));
- }
- }
-
- /* Similarly all functions called by function we just inlined
- are now called more times; update keys. */
-
- for (e = node->callees; e; e = e->next_callee)
- if (!e->inline_call && heap_node[e->callee->uid])
- fibheap_replace_key (heap, heap_node[e->callee->uid],
- cgraph_estimate_growth (e->callee));
- for (i = 0; i < ninlined_callees; i++)
+ /* We need to output all local functions that are used and not
+ always inlined, as well as those that are reachable from
+ outside the current compilation unit. */
+ if (DECL_SAVED_TREE (decl)
+ && !node->global.inlined_to
+ && (node->needed
+ || (e && node->reachable))
+ && !TREE_ASM_WRITTEN (decl)
+ && !DECL_EXTERNAL (decl))
+ node->output = 1;
+ else
{
- struct cgraph_edge *e;
-
- for (e = inlined_callees[i]->callees; e; e = e->next_callee)
- if (!e->inline_call && heap_node[e->callee->uid])
- fibheap_replace_key (heap, heap_node[e->callee->uid],
- cgraph_estimate_growth (e->callee));
+ /* We should've reclaimed all functions that are not needed. */
+#ifdef ENABLE_CHECKING
+ if (!node->global.inlined_to && DECL_SAVED_TREE (decl)
+ && !DECL_EXTERNAL (decl))
+ {
+ dump_cgraph_node (stderr, node);
+ internal_error ("failed to reclaim unneeded function");
+ }
+#endif
+ gcc_assert (node->global.inlined_to || !DECL_SAVED_TREE (decl)
+ || DECL_EXTERNAL (decl));
- inlined_callees[i]->output = 0, node->aux = 0;
}
- if (cgraph_dump_file)
- fprintf (cgraph_dump_file,
- "Created %i clones, Num insns:%i (%+i), %.2f%%.\n\n",
- node->global.cloned_times - 1,
- overall_insns, overall_insns - old_insns,
- overall_insns * 100.0 / initial_insns);
+
}
- if (cgraph_dump_file && !fibheap_empty (heap))
- fprintf (cgraph_dump_file, "inline-unit-growth limit reached.\n");
- fibheap_delete (heap);
- free (heap_node);
}
-/* Decide on the inlining. We do so in the topological order to avoid
- expenses on updating datastructures. */
+/* Expand function specified by NODE. */
static void
-cgraph_decide_inlining (void)
+cgraph_expand_function (struct cgraph_node *node)
{
- struct cgraph_node *node;
- int nnodes;
- struct cgraph_node **order =
- xcalloc (cgraph_n_nodes, sizeof (struct cgraph_node *));
- struct cgraph_node **inlined =
- xcalloc (cgraph_n_nodes, sizeof (struct cgraph_node *));
- struct cgraph_node **inlined_callees =
- xcalloc (cgraph_n_nodes, sizeof (struct cgraph_node *));
- int ninlined;
- int ninlined_callees;
- int i, y;
-
- for (node = cgraph_nodes; node; node = node->next)
- initial_insns += node->local.self_insns;
- overall_insns = initial_insns;
-
- nnodes = cgraph_postorder (order);
-
- for (node = cgraph_nodes; node; node = node->next)
- node->aux = 0;
-
- if (cgraph_dump_file)
- fprintf (cgraph_dump_file, "\n\nDeciding on always_inline functions:\n");
-
- /* In the first pass mark all always_inline edges. Do this with a priority
- so no our decisions makes this impossible. */
- for (i = nnodes - 1; i >= 0; i--)
- {
- struct cgraph_edge *e;
+ tree decl = node->decl;
- node = order[i];
+ /* We ought to not compile any inline clones. */
+ gcc_assert (!node->global.inlined_to);
- for (e = node->callees; e; e = e->next_callee)
- if (e->callee->local.disregard_inline_limits)
- break;
- if (!e)
- continue;
- if (cgraph_dump_file)
- fprintf (cgraph_dump_file,
- "Considering %s %i insns (always inline)\n",
- cgraph_node_name (node), node->global.insns);
- ninlined = cgraph_inlined_into (order[i], inlined);
- for (; e; e = e->next_callee)
- {
- if (e->inline_call || !e->callee->local.disregard_inline_limits)
- continue;
- if (e->callee->output || e->callee == node)
- continue;
- ninlined_callees =
- cgraph_inlined_callees (e->callee, inlined_callees);
- cgraph_mark_inline (node, e->callee, inlined, ninlined,
- inlined_callees, ninlined_callees);
- for (y = 0; y < ninlined_callees; y++)
- inlined_callees[y]->output = 0, node->aux = 0;
- if (cgraph_dump_file)
- fprintf (cgraph_dump_file, "Inlined %i times. Now %i insns\n\n",
- node->global.cloned_times, overall_insns);
- }
- for (y = 0; y < ninlined; y++)
- inlined[y]->output = 0, node->aux = 0;
- }
+ if (flag_unit_at_a_time)
+ announce_function (decl);
- cgraph_decide_inlining_of_small_functions (inlined, inlined_callees);
+ cgraph_lower_function (node);
- if (cgraph_dump_file)
- fprintf (cgraph_dump_file, "\n\nFunctions to inline once:\n");
+ /* Generate RTL for the body of DECL. */
+ lang_hooks.callgraph.expand_function (decl);
- /* And finally decide what functions are called once. */
+ /* Make sure that BE didn't give up on compiling. */
+ /* ??? Can happen with nested function of extern inline. */
+ gcc_assert (TREE_ASM_WRITTEN (node->decl));
- for (i = nnodes - 1; i >= 0; i--)
+ current_function_decl = NULL;
+ if (!cgraph_preserve_function_body_p (node->decl))
{
- node = order[i];
-
- if (node->callers && !node->callers->next_caller && !node->needed
- && node->local.inlinable && !node->callers->inline_call
- && !DECL_EXTERNAL (node->decl) && !DECL_COMDAT (node->decl))
- {
- bool ok = true;
- struct cgraph_node *node1;
-
- /* Verify that we won't duplicate the caller. */
- for (node1 = node->callers->caller;
- node1->callers && node1->callers->inline_call
- && ok; node1 = node1->callers->caller)
- if (node1->callers->next_caller || node1->needed)
- ok = false;
- if (ok)
- {
- if (cgraph_dump_file)
- fprintf (cgraph_dump_file,
- "Considering %s %i insns (called once)\n",
- cgraph_node_name (node), node->global.insns);
- ninlined = cgraph_inlined_into (node->callers->caller, inlined);
- if (cgraph_check_inline_limits
- (node->callers->caller, node, inlined, ninlined))
- {
- ninlined_callees =
- cgraph_inlined_callees (node, inlined_callees);
- cgraph_mark_inline (node->callers->caller, node, inlined,
- ninlined, inlined_callees,
- ninlined_callees);
- for (y = 0; y < ninlined_callees; y++)
- inlined_callees[y]->output = 0, node->aux = 0;
- if (cgraph_dump_file)
- fprintf (cgraph_dump_file, "Inlined. Now %i insns\n\n", overall_insns);
- }
- for (y = 0; y < ninlined; y++)
- inlined[y]->output = 0, node->aux = 0;
- }
- }
+ DECL_SAVED_TREE (node->decl) = NULL;
+ DECL_STRUCT_FUNCTION (node->decl) = NULL;
+ DECL_INITIAL (node->decl) = error_mark_node;
+ /* Eliminate all call edges. This is important so the call_expr no longer
+ points to the dead function body. */
+ cgraph_node_remove_callees (node);
}
- if (cgraph_dump_file)
- fprintf (cgraph_dump_file,
- "\nInlined %i calls, elliminated %i functions, %i insns turned to %i insns.\n",
- ncalls_inlined, nfunctions_inlined, initial_insns,
- overall_insns);
- free (order);
- free (inlined);
- free (inlined_callees);
+ cgraph_function_flags_ready = true;
}
/* Return true when CALLER_DECL should be inlined into CALLEE_DECL. */
bool
-cgraph_inline_p (tree caller_decl, tree callee_decl)
+cgraph_inline_p (struct cgraph_edge *e, const char **reason)
{
- struct cgraph_node *caller = cgraph_node (caller_decl);
- struct cgraph_node *callee = cgraph_node (callee_decl);
- struct cgraph_edge *e;
-
- for (e = caller->callees; e; e = e->next_callee)
- if (e->callee == callee)
- return e->inline_call;
- /* We do not record builtins in the callgraph. Perhaps it would make more
- sense to do so and then prune out those not overwritten by explicit
- function body. */
- return false;
+ *reason = e->inline_failed;
+ return !e->inline_failed;
}
+
+
+
/* Expand all functions that must be output.
Attempt to topologically sort the nodes so function is output when
all called functions are already assembled to allow data to be
propagated across the callgraph. Use a stack to get smaller distance
- between a function and it's callees (later we may choose to use a more
+ between a function and its callees (later we may choose to use a more
sophisticated algorithm for function reordering; we will likely want
to use subsections to make the output functions appear in top-down
order). */
static void
-cgraph_expand_functions (void)
+cgraph_expand_all_functions (void)
{
struct cgraph_node *node;
struct cgraph_node **order =
xcalloc (cgraph_n_nodes, sizeof (struct cgraph_node *));
- int order_pos = 0;
+ int order_pos = 0, new_order_pos = 0;
int i;
- cgraph_mark_functions_to_output ();
-
order_pos = cgraph_postorder (order);
+ gcc_assert (order_pos == cgraph_n_nodes);
- for (i = order_pos - 1; i >= 0; i--)
+ /* Garbage collector may remove inline clones we eliminate during
+ optimization. So we must be sure to not reference them. */
+ for (i = 0; i < order_pos; i++)
+ if (order[i]->output)
+ order[new_order_pos++] = order[i];
+
+ for (i = new_order_pos - 1; i >= 0; i--)
{
node = order[i];
if (node->output)
{
- if (!node->reachable)
- abort ();
+ gcc_assert (node->reachable);
node->output = 0;
cgraph_expand_function (node);
}
free (order);
}
-/* Mark all local functions.
+/* Mark visibility of all functions.
+
+ A local function is one whose calls can occur only in the current
+ compilation unit and all its calls are explicit, so we can change
+ its calling convention. We simply mark all static functions whose
+ address is not taken as local.
- A local function is one whose calls can occur only in the
- current compilation unit, so we change its calling convention.
- We simply mark all static functions whose address is not taken
- as local. */
+ We also change the TREE_PUBLIC flag of all declarations that are public
+ in language point of view but we want to overwrite this default
+ via visibilities for the backend point of view. */
static void
-cgraph_mark_local_functions (void)
+cgraph_function_and_variable_visibility (void)
{
struct cgraph_node *node;
+ struct cgraph_varpool_node *vnode;
- if (cgraph_dump_file)
- fprintf (cgraph_dump_file, "Marking local functions:");
-
- /* Figure out functions we want to assemble. */
for (node = cgraph_nodes; node; node = node->next)
{
+ if (node->reachable
+ && (DECL_COMDAT (node->decl)
+ || (TREE_PUBLIC (node->decl) && !DECL_EXTERNAL (node->decl))))
+ node->local.externally_visible = 1;
node->local.local = (!node->needed
- && DECL_SAVED_TREE (node->decl)
- && !TREE_PUBLIC (node->decl));
- if (cgraph_dump_file && node->local.local)
- fprintf (cgraph_dump_file, " %s", cgraph_node_name (node));
+ && node->analyzed
+ && !DECL_EXTERNAL (node->decl)
+ && !node->local.externally_visible);
+ }
+ for (vnode = cgraph_varpool_nodes_queue; vnode; vnode = vnode->next_needed)
+ {
+ if (vnode->needed
+ && (DECL_COMDAT (vnode->decl) || TREE_PUBLIC (vnode->decl)))
+ vnode->externally_visible = 1;
+ gcc_assert (TREE_STATIC (vnode->decl));
}
+
+ /* Because we have to be conservative on the boundaries of source
+ level units, it is possible that we marked some functions in
+ reachable just because they might be used later via external
+ linkage, but after making them local they are really unreachable
+ now. */
+ cgraph_remove_unreachable_nodes (true, cgraph_dump_file);
+
if (cgraph_dump_file)
- fprintf (cgraph_dump_file, "\n");
+ {
+ fprintf (cgraph_dump_file, "\nMarking local functions:");
+ for (node = cgraph_nodes; node; node = node->next)
+ if (node->local.local)
+ fprintf (cgraph_dump_file, " %s", cgraph_node_name (node));
+ fprintf (cgraph_dump_file, "\n\n");
+ fprintf (cgraph_dump_file, "\nMarking externally visible functions:");
+ for (node = cgraph_nodes; node; node = node->next)
+ if (node->local.externally_visible)
+ fprintf (cgraph_dump_file, " %s", cgraph_node_name (node));
+ fprintf (cgraph_dump_file, "\n\n");
+ }
+ cgraph_function_flags_ready = true;
+}
+
+/* Return true when function body of DECL still needs to be kept around
+ for later re-use. */
+bool
+cgraph_preserve_function_body_p (tree decl)
+{
+ struct cgraph_node *node;
+ /* Keep the body; we're going to dump it. */
+ if (dump_enabled_p (TDI_tree_all))
+ return true;
+ if (!cgraph_global_info_ready)
+ return (DECL_INLINE (decl) && !flag_really_no_inline);
+ /* Look if there is any clone around. */
+ for (node = cgraph_node (decl); node; node = node->next_clone)
+ if (node->global.inlined_to)
+ return true;
+ return false;
}
/* Perform simple optimizations based on callgraph. */
void
cgraph_optimize (void)
{
+#ifdef ENABLE_CHECKING
+ verify_cgraph ();
+#endif
+ if (!flag_unit_at_a_time)
+ {
+ cgraph_varpool_assemble_pending_decls ();
+ return;
+ }
+
+ process_pending_assemble_externals ();
+
+ /* Frontend may output common variables after the unit has been finalized.
+ It is safe to deal with them here as they are always zero initialized. */
+ cgraph_varpool_analyze_pending_decls ();
+
timevar_push (TV_CGRAPHOPT);
if (!quiet_flag)
fprintf (stderr, "Performing intraprocedural optimizations\n");
+
+ cgraph_function_and_variable_visibility ();
if (cgraph_dump_file)
{
- fprintf (cgraph_dump_file, "Initial callgraph:");
+ fprintf (cgraph_dump_file, "Marked ");
dump_cgraph (cgraph_dump_file);
}
- cgraph_mark_local_functions ();
-
- cgraph_decide_inlining ();
-
+ ipa_passes ();
+ /* This pass remove bodies of extern inline functions we never inlined.
+ Do this later so other IPA passes see what is really going on. */
+ cgraph_remove_unreachable_nodes (false, dump_file);
cgraph_global_info_ready = true;
if (cgraph_dump_file)
{
- fprintf (cgraph_dump_file, "Optimized callgraph:");
+ fprintf (cgraph_dump_file, "Optimized ");
dump_cgraph (cgraph_dump_file);
+ dump_varpool (cgraph_dump_file);
}
timevar_pop (TV_CGRAPHOPT);
- if (!quiet_flag)
- fprintf (stderr, "Assembling functions:");
/* Output everything. */
- cgraph_expand_functions ();
+ if (!quiet_flag)
+ fprintf (stderr, "Assembling functions:\n");
+#ifdef ENABLE_CHECKING
+ verify_cgraph ();
+#endif
+
+ cgraph_mark_functions_to_output ();
+ cgraph_expand_all_functions ();
+ cgraph_varpool_remove_unreferenced_decls ();
+
+ cgraph_varpool_assemble_pending_decls ();
+
if (cgraph_dump_file)
{
- fprintf (cgraph_dump_file, "Final callgraph:");
+ fprintf (cgraph_dump_file, "\nFinal ");
dump_cgraph (cgraph_dump_file);
}
+#ifdef ENABLE_CHECKING
+ verify_cgraph ();
+ /* Double check that all inline clones are gone and that all
+ function bodies have been released from memory. */
+ if (flag_unit_at_a_time
+ && !dump_enabled_p (TDI_tree_all)
+ && !(sorrycount || errorcount))
+ {
+ struct cgraph_node *node;
+ bool error_found = false;
+
+ for (node = cgraph_nodes; node; node = node->next)
+ if (node->analyzed
+ && (node->global.inlined_to
+ || DECL_SAVED_TREE (node->decl)))
+ {
+ error_found = true;
+ dump_cgraph_node (stderr, node);
+ }
+ if (error_found)
+ internal_error ("Nodes with no released memory found.");
+ }
+#endif
+}
+
+/* Generate and emit a static constructor or destructor. WHICH must be
+ one of 'I' or 'D'. BODY should be a STATEMENT_LIST containing
+ GENERIC statements. */
+
+void
+cgraph_build_static_cdtor (char which, tree body, int priority)
+{
+ static int counter = 0;
+ char which_buf[16];
+ tree decl, name, resdecl;
+
+ sprintf (which_buf, "%c_%d", which, counter++);
+ name = get_file_function_name_long (which_buf);
+
+ decl = build_decl (FUNCTION_DECL, name,
+ build_function_type (void_type_node, void_list_node));
+ current_function_decl = decl;
+
+ resdecl = build_decl (RESULT_DECL, NULL_TREE, void_type_node);
+ DECL_ARTIFICIAL (resdecl) = 1;
+ DECL_IGNORED_P (resdecl) = 1;
+ DECL_RESULT (decl) = resdecl;
+
+ allocate_struct_function (decl);
+
+ TREE_STATIC (decl) = 1;
+ TREE_USED (decl) = 1;
+ DECL_ARTIFICIAL (decl) = 1;
+ DECL_IGNORED_P (decl) = 1;
+ DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (decl) = 1;
+ DECL_SAVED_TREE (decl) = body;
+ TREE_PUBLIC (decl) = ! targetm.have_ctors_dtors;
+ DECL_UNINLINABLE (decl) = 1;
+
+ DECL_INITIAL (decl) = make_node (BLOCK);
+ TREE_USED (DECL_INITIAL (decl)) = 1;
+
+ DECL_SOURCE_LOCATION (decl) = input_location;
+ cfun->function_end_locus = input_location;
+
+ switch (which)
+ {
+ case 'I':
+ DECL_STATIC_CONSTRUCTOR (decl) = 1;
+ break;
+ case 'D':
+ DECL_STATIC_DESTRUCTOR (decl) = 1;
+ break;
+ default:
+ gcc_unreachable ();
+ }
+
+ gimplify_function_tree (decl);
+
+ /* ??? We will get called LATE in the compilation process. */
+ if (cgraph_global_info_ready)
+ {
+ tree_lowering_passes (decl);
+ tree_rest_of_compilation (decl);
+ }
+ else
+ cgraph_finalize_function (decl, 0);
+
+ if (targetm.have_ctors_dtors)
+ {
+ void (*fn) (rtx, int);
+
+ if (which == 'I')
+ fn = targetm.asm_out.constructor;
+ else
+ fn = targetm.asm_out.destructor;
+ fn (XEXP (DECL_RTL (decl), 0), priority);
+ }
+}
+
+void
+init_cgraph (void)
+{
+ cgraph_dump_file = dump_begin (TDI_cgraph, NULL);
}
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