/* Callgraph handling code.
- Copyright (C) 2003, 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
+ Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008
+ Free Software Foundation, Inc.
Contributed by Jan Hubicka
This file is part of GCC.
#include "hashtab.h"
#include "ggc.h"
#include "timevar.h"
-#include "debug.h"
+#include "debug.h"
#include "target.h"
#include "output.h"
-#include "tree-gimple.h"
+#include "gimple.h"
#include "tree-flow.h"
+#include "flags.h"
/* This file contains basic routines manipulating variable pool.
/* Queue of cgraph nodes scheduled to be lowered and output.
The queue is maintained via mark_needed_node, linked via node->next_needed
- pointer.
+ pointer.
LAST_NEEDED_NODE points to the end of queue, so it can be
- maintained in forward order. QTY is needed to make it friendly to
+ maintained in forward order. GTY is needed to make it friendly to
PCH.
-
- During unit-at-a-time compilation we construct the queue of needed variables
+
+ During compilation we construct the queue of needed variables
twice: first time it is during cgraph construction, second time it is at the
end of compilation in VARPOOL_REMOVE_UNREFERENCED_DECLS so we can avoid
optimized out variables being output.
-
- Each variable is thus first analyzed and then later possibly output.
+
+ Each variable is thus first analyzed and then later possibly output.
FIRST_UNANALYZED_NODE points to first node in queue that was not analyzed
yet and is moved via VARPOOL_ANALYZE_PENDING_DECLS. */
-
+
struct varpool_node *varpool_nodes_queue;
static GTY(()) struct varpool_node *varpool_last_needed_node;
static GTY(()) struct varpool_node *varpool_first_unanalyzed_node;
static GTY(()) struct varpool_node *varpool_assembled_nodes_queue;
/* Return name of the node used in debug output. */
-static const char *
+const char *
varpool_node_name (struct varpool_node *node)
{
return lang_hooks.decl_printable_name (node->decl, 2);
struct varpool_node *node;
fprintf (f, "variable pool:\n\n");
- for (node = varpool_nodes; node; node = node->next_needed)
+ for (node = varpool_nodes; node; node = node->next)
dump_varpool_node (f, node);
}
+/* Dump the variable pool to stderr. */
+
+void
+debug_varpool (void)
+{
+ dump_varpool (stderr);
+}
+
/* Given an assembler name, lookup node. */
struct varpool_node *
varpool_node_for_asm (tree asmname)
/* Determine if variable 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 haven't
- seen yet. */
+ configury */
bool
decide_is_variable_needed (struct varpool_node *node, tree decl)
{
/* If the user told us it is used, then it must be so. */
- if (node->externally_visible || node->force_output)
- return true;
- if (!flag_unit_at_a_time
- && lookup_attribute ("used", DECL_ATTRIBUTES (decl)))
+ if ((node->externally_visible && !DECL_COMDAT (decl))
+ || node->force_output)
return true;
/* ??? If the assembler name is set by hand, it is possible to assemble
&& 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 definition available, then it's still needed. */
- if (node->needed)
- return true;
-
/* Externally visible variables must be output. The exception is
COMDAT variables that must be output only when they are needed. */
- if (TREE_PUBLIC (decl) && !flag_whole_program && !DECL_COMDAT (decl)
+ if (TREE_PUBLIC (decl)
+ && !flag_whole_program
+ && !flag_lto
+ && !flag_whopr
+ && !DECL_COMDAT (decl)
&& !DECL_EXTERNAL (decl))
return true;
/* When not reordering top level variables, we have to assume that
we are going to keep everything. */
- if (flag_unit_at_a_time && flag_toplevel_reorder)
+ if (flag_toplevel_reorder)
return false;
/* We want to emit COMDAT variables only when absolutely necessary. */
{
struct varpool_node *node = varpool_node (decl);
+ /* FIXME: We don't really stream varpool datastructure and instead rebuild it
+ by varpool_finalize_decl. This is not quite correct since this way we can't
+ attach any info to varpool. Eventually we will want to stream varpool nodes
+ and the flags.
+
+ For the moment just prevent analysis of varpool nodes to happen again, so
+ we will re-try to compute "address_taken" flag of varpool that breaks
+ in presence of clones. */
+ if (in_lto_p)
+ node->analyzed = true;
+
/* The first declaration of a variable that comes through this function
decides whether it is global (in C, has external linkage)
or local (in C, has internal linkage). So do nothing more
if this function has already run. */
if (node->finalized)
{
- if (cgraph_global_info_ready || (!flag_unit_at_a_time && !flag_openmp))
+ if (cgraph_global_info_ready)
varpool_assemble_pending_decls ();
return;
}
there. */
else if (TREE_PUBLIC (decl) && !DECL_COMDAT (decl) && !DECL_EXTERNAL (decl))
varpool_mark_needed_node (node);
- if (cgraph_global_info_ready || (!flag_unit_at_a_time && !flag_openmp))
+ if (cgraph_global_info_ready)
varpool_assemble_pending_decls ();
}
while (varpool_first_unanalyzed_node)
{
tree decl = varpool_first_unanalyzed_node->decl;
+ bool analyzed = varpool_first_unanalyzed_node->analyzed;
varpool_first_unanalyzed_node->analyzed = true;
varpool_first_unanalyzed_node = varpool_first_unanalyzed_node->next_needed;
- /* Compute the alignment early so function body expanders are
- already informed about increased alignment. */
- align_variable (decl, 0);
-
+ /* When reading back varpool at LTO time, we re-construct the queue in order
+ to have "needed" list right by inserting all needed nodes into varpool.
+ We however don't want to re-analyze already analyzed nodes. */
+ if (!analyzed)
+ {
+ gcc_assert (!in_lto_p);
+ /* Compute the alignment early so function body expanders are
+ already informed about increased alignment. */
+ align_variable (decl, 0);
+ }
if (DECL_INITIAL (decl))
- record_references_in_initializer (decl);
+ record_references_in_initializer (decl, analyzed);
changed = true;
}
timevar_pop (TV_CGRAPH);
&& (TREE_CODE (decl) != VAR_DECL || !DECL_HAS_VALUE_EXPR_P (decl)))
{
assemble_variable (decl, 0, 1, 0);
- return TREE_ASM_WRITTEN (decl);
+ if (TREE_ASM_WRITTEN (decl))
+ {
+ node->next_needed = varpool_assembled_nodes_queue;
+ varpool_assembled_nodes_queue = node;
+ node->finalized = 1;
+ return true;
+ }
}
return false;
varpool_nodes_queue = varpool_nodes_queue->next_needed;
if (varpool_assemble_decl (node))
- {
- changed = true;
- node->next_needed = varpool_assembled_nodes_queue;
- varpool_assembled_nodes_queue = node;
- node->finalized = 1;
- }
+ changed = true;
else
node->next_needed = NULL;
}
return changed;
}
-/* Output all variables enqueued to be assembled. */
+/* Remove all elements from the queue so we can re-use it for debug output. */
void
-varpool_output_debug_info (void)
+varpool_empty_needed_queue (void)
{
- timevar_push (TV_SYMOUT);
- if (errorcount == 0 && sorrycount == 0)
- while (varpool_assembled_nodes_queue)
- {
- struct varpool_node *node = varpool_assembled_nodes_queue;
-
- /* Local static variables are never seen by check_global_declarations
- so we need to output debug info by hand. */
- if (DECL_CONTEXT (node->decl)
- && (TREE_CODE (DECL_CONTEXT (node->decl)) == BLOCK
- || TREE_CODE (DECL_CONTEXT (node->decl)) == FUNCTION_DECL)
- && errorcount == 0 && sorrycount == 0)
- (*debug_hooks->global_decl) (node->decl);
- varpool_assembled_nodes_queue = node->next_needed;
- node->next_needed = 0;
- }
- timevar_pop (TV_SYMOUT);
+ /* 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. */
+ varpool_analyze_pending_decls ();
+
+ while (varpool_nodes_queue)
+ {
+ struct varpool_node *node = varpool_nodes_queue;
+ varpool_nodes_queue = varpool_nodes_queue->next_needed;
+ node->next_needed = NULL;
+ }
+ /* varpool_nodes_queue is now empty, clear the pointer to the last element
+ in the queue. */
+ varpool_last_needed_node = NULL;
}
/* Create a new global variable of type TYPE. */
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