1157 lines
29 KiB
C
1157 lines
29 KiB
C
/* Control flow graph manipulation code for GNU compiler.
|
||
Copyright (C) 1987, 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
|
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1999, 2000, 2001, 2002, 2003, 2004, 2005
|
||
Free Software Foundation, Inc.
|
||
|
||
This file is part of GCC.
|
||
|
||
GCC is free software; you can redistribute it and/or modify it under
|
||
the terms of the GNU General Public License as published by the Free
|
||
Software Foundation; either version 2, or (at your option) any later
|
||
version.
|
||
|
||
GCC is distributed in the hope that it will be useful, but WITHOUT ANY
|
||
WARRANTY; without even the implied warranty of MERCHANTABILITY or
|
||
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
|
||
for more details.
|
||
|
||
You should have received a copy of the GNU General Public License
|
||
along with GCC; see the file COPYING. If not, write to the Free
|
||
Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
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02110-1301, USA. */
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|
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/* This file contains low level functions to manipulate the CFG and
|
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analyze it. All other modules should not transform the data structure
|
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directly and use abstraction instead. The file is supposed to be
|
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ordered bottom-up and should not contain any code dependent on a
|
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particular intermediate language (RTL or trees).
|
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|
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Available functionality:
|
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- Initialization/deallocation
|
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init_flow, clear_edges
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- Low level basic block manipulation
|
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alloc_block, expunge_block
|
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- Edge manipulation
|
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make_edge, make_single_succ_edge, cached_make_edge, remove_edge
|
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- Low level edge redirection (without updating instruction chain)
|
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redirect_edge_succ, redirect_edge_succ_nodup, redirect_edge_pred
|
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- Dumping and debugging
|
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dump_flow_info, debug_flow_info, dump_edge_info
|
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- Allocation of AUX fields for basic blocks
|
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alloc_aux_for_blocks, free_aux_for_blocks, alloc_aux_for_block
|
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- clear_bb_flags
|
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- Consistency checking
|
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verify_flow_info
|
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- Dumping and debugging
|
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print_rtl_with_bb, dump_bb, debug_bb, debug_bb_n
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*/
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#include "config.h"
|
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#include "system.h"
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#include "coretypes.h"
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#include "tm.h"
|
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#include "tree.h"
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#include "rtl.h"
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#include "hard-reg-set.h"
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#include "regs.h"
|
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#include "flags.h"
|
||
#include "output.h"
|
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#include "function.h"
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#include "except.h"
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#include "toplev.h"
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#include "tm_p.h"
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#include "obstack.h"
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#include "timevar.h"
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#include "tree-pass.h"
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#include "ggc.h"
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#include "hashtab.h"
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#include "alloc-pool.h"
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/* The obstack on which the flow graph components are allocated. */
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struct bitmap_obstack reg_obstack;
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void debug_flow_info (void);
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static void free_edge (edge);
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#define RDIV(X,Y) (((X) + (Y) / 2) / (Y))
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/* Called once at initialization time. */
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void
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init_flow (void)
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{
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if (!cfun->cfg)
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cfun->cfg = ggc_alloc_cleared (sizeof (struct control_flow_graph));
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n_edges = 0;
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ENTRY_BLOCK_PTR = ggc_alloc_cleared (sizeof (struct basic_block_def));
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ENTRY_BLOCK_PTR->index = ENTRY_BLOCK;
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EXIT_BLOCK_PTR = ggc_alloc_cleared (sizeof (struct basic_block_def));
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EXIT_BLOCK_PTR->index = EXIT_BLOCK;
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ENTRY_BLOCK_PTR->next_bb = EXIT_BLOCK_PTR;
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EXIT_BLOCK_PTR->prev_bb = ENTRY_BLOCK_PTR;
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}
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/* Helper function for remove_edge and clear_edges. Frees edge structure
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without actually unlinking it from the pred/succ lists. */
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static void
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free_edge (edge e ATTRIBUTE_UNUSED)
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{
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n_edges--;
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ggc_free (e);
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||
}
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|
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/* Free the memory associated with the edge structures. */
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|
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void
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clear_edges (void)
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{
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basic_block bb;
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edge e;
|
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edge_iterator ei;
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FOR_EACH_BB (bb)
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{
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FOR_EACH_EDGE (e, ei, bb->succs)
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free_edge (e);
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VEC_truncate (edge, bb->succs, 0);
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VEC_truncate (edge, bb->preds, 0);
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}
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FOR_EACH_EDGE (e, ei, ENTRY_BLOCK_PTR->succs)
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free_edge (e);
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VEC_truncate (edge, EXIT_BLOCK_PTR->preds, 0);
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VEC_truncate (edge, ENTRY_BLOCK_PTR->succs, 0);
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gcc_assert (!n_edges);
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}
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/* Allocate memory for basic_block. */
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basic_block
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alloc_block (void)
|
||
{
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basic_block bb;
|
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bb = ggc_alloc_cleared (sizeof (*bb));
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||
return bb;
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||
}
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||
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||
/* Link block B to chain after AFTER. */
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||
void
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||
link_block (basic_block b, basic_block after)
|
||
{
|
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b->next_bb = after->next_bb;
|
||
b->prev_bb = after;
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||
after->next_bb = b;
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b->next_bb->prev_bb = b;
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||
}
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||
|
||
/* Unlink block B from chain. */
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void
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||
unlink_block (basic_block b)
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||
{
|
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b->next_bb->prev_bb = b->prev_bb;
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b->prev_bb->next_bb = b->next_bb;
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b->prev_bb = NULL;
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b->next_bb = NULL;
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}
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||
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/* Sequentially order blocks and compact the arrays. */
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||
void
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||
compact_blocks (void)
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||
{
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int i;
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basic_block bb;
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SET_BASIC_BLOCK (ENTRY_BLOCK, ENTRY_BLOCK_PTR);
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SET_BASIC_BLOCK (EXIT_BLOCK, EXIT_BLOCK_PTR);
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i = NUM_FIXED_BLOCKS;
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FOR_EACH_BB (bb)
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{
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SET_BASIC_BLOCK (i, bb);
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bb->index = i;
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i++;
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}
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gcc_assert (i == n_basic_blocks);
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for (; i < last_basic_block; i++)
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SET_BASIC_BLOCK (i, NULL);
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last_basic_block = n_basic_blocks;
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}
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/* Remove block B from the basic block array. */
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void
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expunge_block (basic_block b)
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||
{
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unlink_block (b);
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SET_BASIC_BLOCK (b->index, NULL);
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n_basic_blocks--;
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/* We should be able to ggc_free here, but we are not.
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The dead SSA_NAMES are left pointing to dead statements that are pointing
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to dead basic blocks making garbage collector to die.
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We should be able to release all dead SSA_NAMES and at the same time we should
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||
clear out BB pointer of dead statements consistently. */
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||
}
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/* Connect E to E->src. */
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static inline void
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||
connect_src (edge e)
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||
{
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VEC_safe_push (edge, gc, e->src->succs, e);
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||
}
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||
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/* Connect E to E->dest. */
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static inline void
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||
connect_dest (edge e)
|
||
{
|
||
basic_block dest = e->dest;
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||
VEC_safe_push (edge, gc, dest->preds, e);
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||
e->dest_idx = EDGE_COUNT (dest->preds) - 1;
|
||
}
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||
|
||
/* Disconnect edge E from E->src. */
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||
|
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static inline void
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||
disconnect_src (edge e)
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||
{
|
||
basic_block src = e->src;
|
||
edge_iterator ei;
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||
edge tmp;
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||
|
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for (ei = ei_start (src->succs); (tmp = ei_safe_edge (ei)); )
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||
{
|
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if (tmp == e)
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{
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VEC_unordered_remove (edge, src->succs, ei.index);
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return;
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||
}
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else
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ei_next (&ei);
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}
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gcc_unreachable ();
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}
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||
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/* Disconnect edge E from E->dest. */
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||
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static inline void
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||
disconnect_dest (edge e)
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||
{
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basic_block dest = e->dest;
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unsigned int dest_idx = e->dest_idx;
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VEC_unordered_remove (edge, dest->preds, dest_idx);
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/* If we removed an edge in the middle of the edge vector, we need
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to update dest_idx of the edge that moved into the "hole". */
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if (dest_idx < EDGE_COUNT (dest->preds))
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EDGE_PRED (dest, dest_idx)->dest_idx = dest_idx;
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}
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/* Create an edge connecting SRC and DEST with flags FLAGS. Return newly
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created edge. Use this only if you are sure that this edge can't
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possibly already exist. */
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edge
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unchecked_make_edge (basic_block src, basic_block dst, int flags)
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{
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edge e;
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e = ggc_alloc_cleared (sizeof (*e));
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n_edges++;
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e->src = src;
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e->dest = dst;
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e->flags = flags;
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connect_src (e);
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connect_dest (e);
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execute_on_growing_pred (e);
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return e;
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}
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/* Create an edge connecting SRC and DST with FLAGS optionally using
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edge cache CACHE. Return the new edge, NULL if already exist. */
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edge
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cached_make_edge (sbitmap edge_cache, basic_block src, basic_block dst, int flags)
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{
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if (edge_cache == NULL
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|| src == ENTRY_BLOCK_PTR
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|| dst == EXIT_BLOCK_PTR)
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return make_edge (src, dst, flags);
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||
/* Does the requested edge already exist? */
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if (! TEST_BIT (edge_cache, dst->index))
|
||
{
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/* The edge does not exist. Create one and update the
|
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cache. */
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SET_BIT (edge_cache, dst->index);
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return unchecked_make_edge (src, dst, flags);
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}
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/* At this point, we know that the requested edge exists. Adjust
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flags if necessary. */
|
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if (flags)
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||
{
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edge e = find_edge (src, dst);
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e->flags |= flags;
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}
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return NULL;
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}
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||
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||
/* Create an edge connecting SRC and DEST with flags FLAGS. Return newly
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created edge or NULL if already exist. */
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||
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edge
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make_edge (basic_block src, basic_block dest, int flags)
|
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{
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edge e = find_edge (src, dest);
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||
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/* Make sure we don't add duplicate edges. */
|
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if (e)
|
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{
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e->flags |= flags;
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return NULL;
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||
}
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||
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return unchecked_make_edge (src, dest, flags);
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||
}
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||
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/* Create an edge connecting SRC to DEST and set probability by knowing
|
||
that it is the single edge leaving SRC. */
|
||
|
||
edge
|
||
make_single_succ_edge (basic_block src, basic_block dest, int flags)
|
||
{
|
||
edge e = make_edge (src, dest, flags);
|
||
|
||
e->probability = REG_BR_PROB_BASE;
|
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e->count = src->count;
|
||
return e;
|
||
}
|
||
|
||
/* This function will remove an edge from the flow graph. */
|
||
|
||
void
|
||
remove_edge (edge e)
|
||
{
|
||
remove_predictions_associated_with_edge (e);
|
||
execute_on_shrinking_pred (e);
|
||
|
||
disconnect_src (e);
|
||
disconnect_dest (e);
|
||
|
||
free_edge (e);
|
||
}
|
||
|
||
/* Redirect an edge's successor from one block to another. */
|
||
|
||
void
|
||
redirect_edge_succ (edge e, basic_block new_succ)
|
||
{
|
||
execute_on_shrinking_pred (e);
|
||
|
||
disconnect_dest (e);
|
||
|
||
e->dest = new_succ;
|
||
|
||
/* Reconnect the edge to the new successor block. */
|
||
connect_dest (e);
|
||
|
||
execute_on_growing_pred (e);
|
||
}
|
||
|
||
/* Like previous but avoid possible duplicate edge. */
|
||
|
||
edge
|
||
redirect_edge_succ_nodup (edge e, basic_block new_succ)
|
||
{
|
||
edge s;
|
||
|
||
s = find_edge (e->src, new_succ);
|
||
if (s && s != e)
|
||
{
|
||
s->flags |= e->flags;
|
||
s->probability += e->probability;
|
||
if (s->probability > REG_BR_PROB_BASE)
|
||
s->probability = REG_BR_PROB_BASE;
|
||
s->count += e->count;
|
||
remove_edge (e);
|
||
e = s;
|
||
}
|
||
else
|
||
redirect_edge_succ (e, new_succ);
|
||
|
||
return e;
|
||
}
|
||
|
||
/* Redirect an edge's predecessor from one block to another. */
|
||
|
||
void
|
||
redirect_edge_pred (edge e, basic_block new_pred)
|
||
{
|
||
disconnect_src (e);
|
||
|
||
e->src = new_pred;
|
||
|
||
/* Reconnect the edge to the new predecessor block. */
|
||
connect_src (e);
|
||
}
|
||
|
||
/* Clear all basic block flags, with the exception of partitioning. */
|
||
void
|
||
clear_bb_flags (void)
|
||
{
|
||
basic_block bb;
|
||
|
||
FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR, NULL, next_bb)
|
||
bb->flags = (BB_PARTITION (bb) | (bb->flags & BB_DISABLE_SCHEDULE)
|
||
| (bb->flags & BB_RTL));
|
||
}
|
||
|
||
/* Check the consistency of profile information. We can't do that
|
||
in verify_flow_info, as the counts may get invalid for incompletely
|
||
solved graphs, later eliminating of conditionals or roundoff errors.
|
||
It is still practical to have them reported for debugging of simple
|
||
testcases. */
|
||
void
|
||
check_bb_profile (basic_block bb, FILE * file)
|
||
{
|
||
edge e;
|
||
int sum = 0;
|
||
gcov_type lsum;
|
||
edge_iterator ei;
|
||
|
||
if (profile_status == PROFILE_ABSENT)
|
||
return;
|
||
|
||
if (bb != EXIT_BLOCK_PTR)
|
||
{
|
||
FOR_EACH_EDGE (e, ei, bb->succs)
|
||
sum += e->probability;
|
||
if (EDGE_COUNT (bb->succs) && abs (sum - REG_BR_PROB_BASE) > 100)
|
||
fprintf (file, "Invalid sum of outgoing probabilities %.1f%%\n",
|
||
sum * 100.0 / REG_BR_PROB_BASE);
|
||
lsum = 0;
|
||
FOR_EACH_EDGE (e, ei, bb->succs)
|
||
lsum += e->count;
|
||
if (EDGE_COUNT (bb->succs)
|
||
&& (lsum - bb->count > 100 || lsum - bb->count < -100))
|
||
fprintf (file, "Invalid sum of outgoing counts %i, should be %i\n",
|
||
(int) lsum, (int) bb->count);
|
||
}
|
||
if (bb != ENTRY_BLOCK_PTR)
|
||
{
|
||
sum = 0;
|
||
FOR_EACH_EDGE (e, ei, bb->preds)
|
||
sum += EDGE_FREQUENCY (e);
|
||
if (abs (sum - bb->frequency) > 100)
|
||
fprintf (file,
|
||
"Invalid sum of incoming frequencies %i, should be %i\n",
|
||
sum, bb->frequency);
|
||
lsum = 0;
|
||
FOR_EACH_EDGE (e, ei, bb->preds)
|
||
lsum += e->count;
|
||
if (lsum - bb->count > 100 || lsum - bb->count < -100)
|
||
fprintf (file, "Invalid sum of incoming counts %i, should be %i\n",
|
||
(int) lsum, (int) bb->count);
|
||
}
|
||
}
|
||
|
||
/* Emit basic block information for BB. HEADER is true if the user wants
|
||
the generic information and the predecessors, FOOTER is true if they want
|
||
the successors. FLAGS is the dump flags of interest; TDF_DETAILS emit
|
||
global register liveness information. PREFIX is put in front of every
|
||
line. The output is emitted to FILE. */
|
||
void
|
||
dump_bb_info (basic_block bb, bool header, bool footer, int flags,
|
||
const char *prefix, FILE *file)
|
||
{
|
||
edge e;
|
||
edge_iterator ei;
|
||
|
||
if (header)
|
||
{
|
||
fprintf (file, "\n%sBasic block %d ", prefix, bb->index);
|
||
if (bb->prev_bb)
|
||
fprintf (file, ", prev %d", bb->prev_bb->index);
|
||
if (bb->next_bb)
|
||
fprintf (file, ", next %d", bb->next_bb->index);
|
||
fprintf (file, ", loop_depth %d, count ", bb->loop_depth);
|
||
fprintf (file, HOST_WIDEST_INT_PRINT_DEC, bb->count);
|
||
fprintf (file, ", freq %i", bb->frequency);
|
||
if (maybe_hot_bb_p (bb))
|
||
fprintf (file, ", maybe hot");
|
||
if (probably_never_executed_bb_p (bb))
|
||
fprintf (file, ", probably never executed");
|
||
fprintf (file, ".\n");
|
||
|
||
fprintf (file, "%sPredecessors: ", prefix);
|
||
FOR_EACH_EDGE (e, ei, bb->preds)
|
||
dump_edge_info (file, e, 0);
|
||
}
|
||
|
||
if (footer)
|
||
{
|
||
fprintf (file, "\n%sSuccessors: ", prefix);
|
||
FOR_EACH_EDGE (e, ei, bb->succs)
|
||
dump_edge_info (file, e, 1);
|
||
}
|
||
|
||
if ((flags & TDF_DETAILS)
|
||
&& (bb->flags & BB_RTL))
|
||
{
|
||
if (bb->il.rtl->global_live_at_start && header)
|
||
{
|
||
fprintf (file, "\n%sRegisters live at start:", prefix);
|
||
dump_regset (bb->il.rtl->global_live_at_start, file);
|
||
}
|
||
|
||
if (bb->il.rtl->global_live_at_end && footer)
|
||
{
|
||
fprintf (file, "\n%sRegisters live at end:", prefix);
|
||
dump_regset (bb->il.rtl->global_live_at_end, file);
|
||
}
|
||
}
|
||
|
||
putc ('\n', file);
|
||
}
|
||
|
||
void
|
||
dump_flow_info (FILE *file, int flags)
|
||
{
|
||
basic_block bb;
|
||
|
||
/* There are no pseudo registers after reload. Don't dump them. */
|
||
if (reg_n_info && !reload_completed
|
||
&& (flags & TDF_DETAILS) != 0)
|
||
{
|
||
unsigned int i, max = max_reg_num ();
|
||
fprintf (file, "%d registers.\n", max);
|
||
for (i = FIRST_PSEUDO_REGISTER; i < max; i++)
|
||
if (REG_N_REFS (i))
|
||
{
|
||
enum reg_class class, altclass;
|
||
|
||
fprintf (file, "\nRegister %d used %d times across %d insns",
|
||
i, REG_N_REFS (i), REG_LIVE_LENGTH (i));
|
||
if (REG_BASIC_BLOCK (i) >= 0)
|
||
fprintf (file, " in block %d", REG_BASIC_BLOCK (i));
|
||
if (REG_N_SETS (i))
|
||
fprintf (file, "; set %d time%s", REG_N_SETS (i),
|
||
(REG_N_SETS (i) == 1) ? "" : "s");
|
||
if (regno_reg_rtx[i] != NULL && REG_USERVAR_P (regno_reg_rtx[i]))
|
||
fprintf (file, "; user var");
|
||
if (REG_N_DEATHS (i) != 1)
|
||
fprintf (file, "; dies in %d places", REG_N_DEATHS (i));
|
||
if (REG_N_CALLS_CROSSED (i) == 1)
|
||
fprintf (file, "; crosses 1 call");
|
||
else if (REG_N_CALLS_CROSSED (i))
|
||
fprintf (file, "; crosses %d calls", REG_N_CALLS_CROSSED (i));
|
||
if (regno_reg_rtx[i] != NULL
|
||
&& PSEUDO_REGNO_BYTES (i) != UNITS_PER_WORD)
|
||
fprintf (file, "; %d bytes", PSEUDO_REGNO_BYTES (i));
|
||
|
||
class = reg_preferred_class (i);
|
||
altclass = reg_alternate_class (i);
|
||
if (class != GENERAL_REGS || altclass != ALL_REGS)
|
||
{
|
||
if (altclass == ALL_REGS || class == ALL_REGS)
|
||
fprintf (file, "; pref %s", reg_class_names[(int) class]);
|
||
else if (altclass == NO_REGS)
|
||
fprintf (file, "; %s or none", reg_class_names[(int) class]);
|
||
else
|
||
fprintf (file, "; pref %s, else %s",
|
||
reg_class_names[(int) class],
|
||
reg_class_names[(int) altclass]);
|
||
}
|
||
|
||
if (regno_reg_rtx[i] != NULL && REG_POINTER (regno_reg_rtx[i]))
|
||
fprintf (file, "; pointer");
|
||
fprintf (file, ".\n");
|
||
}
|
||
}
|
||
|
||
fprintf (file, "\n%d basic blocks, %d edges.\n", n_basic_blocks, n_edges);
|
||
FOR_EACH_BB (bb)
|
||
{
|
||
dump_bb_info (bb, true, true, flags, "", file);
|
||
check_bb_profile (bb, file);
|
||
}
|
||
|
||
putc ('\n', file);
|
||
}
|
||
|
||
void
|
||
debug_flow_info (void)
|
||
{
|
||
dump_flow_info (stderr, TDF_DETAILS);
|
||
}
|
||
|
||
void
|
||
dump_edge_info (FILE *file, edge e, int do_succ)
|
||
{
|
||
basic_block side = (do_succ ? e->dest : e->src);
|
||
|
||
if (side == ENTRY_BLOCK_PTR)
|
||
fputs (" ENTRY", file);
|
||
else if (side == EXIT_BLOCK_PTR)
|
||
fputs (" EXIT", file);
|
||
else
|
||
fprintf (file, " %d", side->index);
|
||
|
||
if (e->probability)
|
||
fprintf (file, " [%.1f%%] ", e->probability * 100.0 / REG_BR_PROB_BASE);
|
||
|
||
if (e->count)
|
||
{
|
||
fprintf (file, " count:");
|
||
fprintf (file, HOST_WIDEST_INT_PRINT_DEC, e->count);
|
||
}
|
||
|
||
if (e->flags)
|
||
{
|
||
static const char * const bitnames[] = {
|
||
"fallthru", "ab", "abcall", "eh", "fake", "dfs_back",
|
||
"can_fallthru", "irreducible", "sibcall", "loop_exit",
|
||
"true", "false", "exec"
|
||
};
|
||
int comma = 0;
|
||
int i, flags = e->flags;
|
||
|
||
fputs (" (", file);
|
||
for (i = 0; flags; i++)
|
||
if (flags & (1 << i))
|
||
{
|
||
flags &= ~(1 << i);
|
||
|
||
if (comma)
|
||
fputc (',', file);
|
||
if (i < (int) ARRAY_SIZE (bitnames))
|
||
fputs (bitnames[i], file);
|
||
else
|
||
fprintf (file, "%d", i);
|
||
comma = 1;
|
||
}
|
||
|
||
fputc (')', file);
|
||
}
|
||
}
|
||
|
||
/* Simple routines to easily allocate AUX fields of basic blocks. */
|
||
|
||
static struct obstack block_aux_obstack;
|
||
static void *first_block_aux_obj = 0;
|
||
static struct obstack edge_aux_obstack;
|
||
static void *first_edge_aux_obj = 0;
|
||
|
||
/* Allocate a memory block of SIZE as BB->aux. The obstack must
|
||
be first initialized by alloc_aux_for_blocks. */
|
||
|
||
inline void
|
||
alloc_aux_for_block (basic_block bb, int size)
|
||
{
|
||
/* Verify that aux field is clear. */
|
||
gcc_assert (!bb->aux && first_block_aux_obj);
|
||
bb->aux = obstack_alloc (&block_aux_obstack, size);
|
||
memset (bb->aux, 0, size);
|
||
}
|
||
|
||
/* Initialize the block_aux_obstack and if SIZE is nonzero, call
|
||
alloc_aux_for_block for each basic block. */
|
||
|
||
void
|
||
alloc_aux_for_blocks (int size)
|
||
{
|
||
static int initialized;
|
||
|
||
if (!initialized)
|
||
{
|
||
gcc_obstack_init (&block_aux_obstack);
|
||
initialized = 1;
|
||
}
|
||
else
|
||
/* Check whether AUX data are still allocated. */
|
||
gcc_assert (!first_block_aux_obj);
|
||
|
||
first_block_aux_obj = obstack_alloc (&block_aux_obstack, 0);
|
||
if (size)
|
||
{
|
||
basic_block bb;
|
||
|
||
FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR, NULL, next_bb)
|
||
alloc_aux_for_block (bb, size);
|
||
}
|
||
}
|
||
|
||
/* Clear AUX pointers of all blocks. */
|
||
|
||
void
|
||
clear_aux_for_blocks (void)
|
||
{
|
||
basic_block bb;
|
||
|
||
FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR, NULL, next_bb)
|
||
bb->aux = NULL;
|
||
}
|
||
|
||
/* Free data allocated in block_aux_obstack and clear AUX pointers
|
||
of all blocks. */
|
||
|
||
void
|
||
free_aux_for_blocks (void)
|
||
{
|
||
gcc_assert (first_block_aux_obj);
|
||
obstack_free (&block_aux_obstack, first_block_aux_obj);
|
||
first_block_aux_obj = NULL;
|
||
|
||
clear_aux_for_blocks ();
|
||
}
|
||
|
||
/* Allocate a memory edge of SIZE as BB->aux. The obstack must
|
||
be first initialized by alloc_aux_for_edges. */
|
||
|
||
inline void
|
||
alloc_aux_for_edge (edge e, int size)
|
||
{
|
||
/* Verify that aux field is clear. */
|
||
gcc_assert (!e->aux && first_edge_aux_obj);
|
||
e->aux = obstack_alloc (&edge_aux_obstack, size);
|
||
memset (e->aux, 0, size);
|
||
}
|
||
|
||
/* Initialize the edge_aux_obstack and if SIZE is nonzero, call
|
||
alloc_aux_for_edge for each basic edge. */
|
||
|
||
void
|
||
alloc_aux_for_edges (int size)
|
||
{
|
||
static int initialized;
|
||
|
||
if (!initialized)
|
||
{
|
||
gcc_obstack_init (&edge_aux_obstack);
|
||
initialized = 1;
|
||
}
|
||
else
|
||
/* Check whether AUX data are still allocated. */
|
||
gcc_assert (!first_edge_aux_obj);
|
||
|
||
first_edge_aux_obj = obstack_alloc (&edge_aux_obstack, 0);
|
||
if (size)
|
||
{
|
||
basic_block bb;
|
||
|
||
FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR, EXIT_BLOCK_PTR, next_bb)
|
||
{
|
||
edge e;
|
||
edge_iterator ei;
|
||
|
||
FOR_EACH_EDGE (e, ei, bb->succs)
|
||
alloc_aux_for_edge (e, size);
|
||
}
|
||
}
|
||
}
|
||
|
||
/* Clear AUX pointers of all edges. */
|
||
|
||
void
|
||
clear_aux_for_edges (void)
|
||
{
|
||
basic_block bb;
|
||
edge e;
|
||
|
||
FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR, EXIT_BLOCK_PTR, next_bb)
|
||
{
|
||
edge_iterator ei;
|
||
FOR_EACH_EDGE (e, ei, bb->succs)
|
||
e->aux = NULL;
|
||
}
|
||
}
|
||
|
||
/* Free data allocated in edge_aux_obstack and clear AUX pointers
|
||
of all edges. */
|
||
|
||
void
|
||
free_aux_for_edges (void)
|
||
{
|
||
gcc_assert (first_edge_aux_obj);
|
||
obstack_free (&edge_aux_obstack, first_edge_aux_obj);
|
||
first_edge_aux_obj = NULL;
|
||
|
||
clear_aux_for_edges ();
|
||
}
|
||
|
||
void
|
||
debug_bb (basic_block bb)
|
||
{
|
||
dump_bb (bb, stderr, 0);
|
||
}
|
||
|
||
basic_block
|
||
debug_bb_n (int n)
|
||
{
|
||
basic_block bb = BASIC_BLOCK (n);
|
||
dump_bb (bb, stderr, 0);
|
||
return bb;
|
||
}
|
||
|
||
/* Dumps cfg related information about basic block BB to FILE. */
|
||
|
||
static void
|
||
dump_cfg_bb_info (FILE *file, basic_block bb)
|
||
{
|
||
unsigned i;
|
||
edge_iterator ei;
|
||
bool first = true;
|
||
static const char * const bb_bitnames[] =
|
||
{
|
||
"dirty", "new", "reachable", "visited", "irreducible_loop", "superblock"
|
||
};
|
||
const unsigned n_bitnames = sizeof (bb_bitnames) / sizeof (char *);
|
||
edge e;
|
||
|
||
fprintf (file, "Basic block %d", bb->index);
|
||
for (i = 0; i < n_bitnames; i++)
|
||
if (bb->flags & (1 << i))
|
||
{
|
||
if (first)
|
||
fprintf (file, " (");
|
||
else
|
||
fprintf (file, ", ");
|
||
first = false;
|
||
fprintf (file, "%s", bb_bitnames[i]);
|
||
}
|
||
if (!first)
|
||
fprintf (file, ")");
|
||
fprintf (file, "\n");
|
||
|
||
fprintf (file, "Predecessors: ");
|
||
FOR_EACH_EDGE (e, ei, bb->preds)
|
||
dump_edge_info (file, e, 0);
|
||
|
||
fprintf (file, "\nSuccessors: ");
|
||
FOR_EACH_EDGE (e, ei, bb->succs)
|
||
dump_edge_info (file, e, 1);
|
||
fprintf (file, "\n\n");
|
||
}
|
||
|
||
/* Dumps a brief description of cfg to FILE. */
|
||
|
||
void
|
||
brief_dump_cfg (FILE *file)
|
||
{
|
||
basic_block bb;
|
||
|
||
FOR_EACH_BB (bb)
|
||
{
|
||
dump_cfg_bb_info (file, bb);
|
||
}
|
||
}
|
||
|
||
/* An edge originally destinating BB of FREQUENCY and COUNT has been proved to
|
||
leave the block by TAKEN_EDGE. Update profile of BB such that edge E can be
|
||
redirected to destination of TAKEN_EDGE.
|
||
|
||
This function may leave the profile inconsistent in the case TAKEN_EDGE
|
||
frequency or count is believed to be lower than FREQUENCY or COUNT
|
||
respectively. */
|
||
void
|
||
update_bb_profile_for_threading (basic_block bb, int edge_frequency,
|
||
gcov_type count, edge taken_edge)
|
||
{
|
||
edge c;
|
||
int prob;
|
||
edge_iterator ei;
|
||
|
||
bb->count -= count;
|
||
if (bb->count < 0)
|
||
{
|
||
if (dump_file)
|
||
fprintf (dump_file, "bb %i count became negative after threading",
|
||
bb->index);
|
||
bb->count = 0;
|
||
}
|
||
|
||
/* Compute the probability of TAKEN_EDGE being reached via threaded edge.
|
||
Watch for overflows. */
|
||
if (bb->frequency)
|
||
prob = edge_frequency * REG_BR_PROB_BASE / bb->frequency;
|
||
else
|
||
prob = 0;
|
||
if (prob > taken_edge->probability)
|
||
{
|
||
if (dump_file)
|
||
fprintf (dump_file, "Jump threading proved probability of edge "
|
||
"%i->%i too small (it is %i, should be %i).\n",
|
||
taken_edge->src->index, taken_edge->dest->index,
|
||
taken_edge->probability, prob);
|
||
prob = taken_edge->probability;
|
||
}
|
||
|
||
/* Now rescale the probabilities. */
|
||
taken_edge->probability -= prob;
|
||
prob = REG_BR_PROB_BASE - prob;
|
||
bb->frequency -= edge_frequency;
|
||
if (bb->frequency < 0)
|
||
bb->frequency = 0;
|
||
if (prob <= 0)
|
||
{
|
||
if (dump_file)
|
||
fprintf (dump_file, "Edge frequencies of bb %i has been reset, "
|
||
"frequency of block should end up being 0, it is %i\n",
|
||
bb->index, bb->frequency);
|
||
EDGE_SUCC (bb, 0)->probability = REG_BR_PROB_BASE;
|
||
ei = ei_start (bb->succs);
|
||
ei_next (&ei);
|
||
for (; (c = ei_safe_edge (ei)); ei_next (&ei))
|
||
c->probability = 0;
|
||
}
|
||
else if (prob != REG_BR_PROB_BASE)
|
||
{
|
||
int scale = RDIV (65536 * REG_BR_PROB_BASE, prob);
|
||
|
||
FOR_EACH_EDGE (c, ei, bb->succs)
|
||
{
|
||
c->probability = RDIV (c->probability * scale, 65536);
|
||
if (c->probability > REG_BR_PROB_BASE)
|
||
c->probability = REG_BR_PROB_BASE;
|
||
}
|
||
}
|
||
|
||
gcc_assert (bb == taken_edge->src);
|
||
taken_edge->count -= count;
|
||
if (taken_edge->count < 0)
|
||
{
|
||
if (dump_file)
|
||
fprintf (dump_file, "edge %i->%i count became negative after threading",
|
||
taken_edge->src->index, taken_edge->dest->index);
|
||
taken_edge->count = 0;
|
||
}
|
||
}
|
||
|
||
/* Multiply all frequencies of basic blocks in array BBS of length NBBS
|
||
by NUM/DEN, in int arithmetic. May lose some accuracy. */
|
||
void
|
||
scale_bbs_frequencies_int (basic_block *bbs, int nbbs, int num, int den)
|
||
{
|
||
int i;
|
||
edge e;
|
||
if (num < 0)
|
||
num = 0;
|
||
if (num > den)
|
||
return;
|
||
/* Assume that the users are producing the fraction from frequencies
|
||
that never grow far enough to risk arithmetic overflow. */
|
||
gcc_assert (num < 65536);
|
||
for (i = 0; i < nbbs; i++)
|
||
{
|
||
edge_iterator ei;
|
||
bbs[i]->frequency = RDIV (bbs[i]->frequency * num, den);
|
||
bbs[i]->count = RDIV (bbs[i]->count * num, den);
|
||
FOR_EACH_EDGE (e, ei, bbs[i]->succs)
|
||
e->count = RDIV (e->count * num, den);
|
||
}
|
||
}
|
||
|
||
/* numbers smaller than this value are safe to multiply without getting
|
||
64bit overflow. */
|
||
#define MAX_SAFE_MULTIPLIER (1 << (sizeof (HOST_WIDEST_INT) * 4 - 1))
|
||
|
||
/* Multiply all frequencies of basic blocks in array BBS of length NBBS
|
||
by NUM/DEN, in gcov_type arithmetic. More accurate than previous
|
||
function but considerably slower. */
|
||
void
|
||
scale_bbs_frequencies_gcov_type (basic_block *bbs, int nbbs, gcov_type num,
|
||
gcov_type den)
|
||
{
|
||
int i;
|
||
edge e;
|
||
gcov_type fraction = RDIV (num * 65536, den);
|
||
|
||
gcc_assert (fraction >= 0);
|
||
|
||
if (num < MAX_SAFE_MULTIPLIER)
|
||
for (i = 0; i < nbbs; i++)
|
||
{
|
||
edge_iterator ei;
|
||
bbs[i]->frequency = RDIV (bbs[i]->frequency * num, den);
|
||
if (bbs[i]->count <= MAX_SAFE_MULTIPLIER)
|
||
bbs[i]->count = RDIV (bbs[i]->count * num, den);
|
||
else
|
||
bbs[i]->count = RDIV (bbs[i]->count * fraction, 65536);
|
||
FOR_EACH_EDGE (e, ei, bbs[i]->succs)
|
||
if (bbs[i]->count <= MAX_SAFE_MULTIPLIER)
|
||
e->count = RDIV (e->count * num, den);
|
||
else
|
||
e->count = RDIV (e->count * fraction, 65536);
|
||
}
|
||
else
|
||
for (i = 0; i < nbbs; i++)
|
||
{
|
||
edge_iterator ei;
|
||
if (sizeof (gcov_type) > sizeof (int))
|
||
bbs[i]->frequency = RDIV (bbs[i]->frequency * num, den);
|
||
else
|
||
bbs[i]->frequency = RDIV (bbs[i]->frequency * fraction, 65536);
|
||
bbs[i]->count = RDIV (bbs[i]->count * fraction, 65536);
|
||
FOR_EACH_EDGE (e, ei, bbs[i]->succs)
|
||
e->count = RDIV (e->count * fraction, 65536);
|
||
}
|
||
}
|
||
|
||
/* Data structures used to maintain mapping between basic blocks and
|
||
copies. */
|
||
static htab_t bb_original;
|
||
static htab_t bb_copy;
|
||
static alloc_pool original_copy_bb_pool;
|
||
|
||
struct htab_bb_copy_original_entry
|
||
{
|
||
/* Block we are attaching info to. */
|
||
int index1;
|
||
/* Index of original or copy (depending on the hashtable) */
|
||
int index2;
|
||
};
|
||
|
||
static hashval_t
|
||
bb_copy_original_hash (const void *p)
|
||
{
|
||
struct htab_bb_copy_original_entry *data
|
||
= ((struct htab_bb_copy_original_entry *)p);
|
||
|
||
return data->index1;
|
||
}
|
||
static int
|
||
bb_copy_original_eq (const void *p, const void *q)
|
||
{
|
||
struct htab_bb_copy_original_entry *data
|
||
= ((struct htab_bb_copy_original_entry *)p);
|
||
struct htab_bb_copy_original_entry *data2
|
||
= ((struct htab_bb_copy_original_entry *)q);
|
||
|
||
return data->index1 == data2->index1;
|
||
}
|
||
|
||
/* Initialize the data structures to maintain mapping between blocks
|
||
and its copies. */
|
||
void
|
||
initialize_original_copy_tables (void)
|
||
{
|
||
gcc_assert (!original_copy_bb_pool);
|
||
original_copy_bb_pool
|
||
= create_alloc_pool ("original_copy",
|
||
sizeof (struct htab_bb_copy_original_entry), 10);
|
||
bb_original = htab_create (10, bb_copy_original_hash,
|
||
bb_copy_original_eq, NULL);
|
||
bb_copy = htab_create (10, bb_copy_original_hash, bb_copy_original_eq, NULL);
|
||
}
|
||
|
||
/* Free the data structures to maintain mapping between blocks and
|
||
its copies. */
|
||
void
|
||
free_original_copy_tables (void)
|
||
{
|
||
gcc_assert (original_copy_bb_pool);
|
||
htab_delete (bb_copy);
|
||
htab_delete (bb_original);
|
||
free_alloc_pool (original_copy_bb_pool);
|
||
bb_copy = NULL;
|
||
bb_original = NULL;
|
||
original_copy_bb_pool = NULL;
|
||
}
|
||
|
||
/* Set original for basic block. Do nothing when data structures are not
|
||
initialized so passes not needing this don't need to care. */
|
||
void
|
||
set_bb_original (basic_block bb, basic_block original)
|
||
{
|
||
if (original_copy_bb_pool)
|
||
{
|
||
struct htab_bb_copy_original_entry **slot;
|
||
struct htab_bb_copy_original_entry key;
|
||
|
||
key.index1 = bb->index;
|
||
slot =
|
||
(struct htab_bb_copy_original_entry **) htab_find_slot (bb_original,
|
||
&key, INSERT);
|
||
if (*slot)
|
||
(*slot)->index2 = original->index;
|
||
else
|
||
{
|
||
*slot = pool_alloc (original_copy_bb_pool);
|
||
(*slot)->index1 = bb->index;
|
||
(*slot)->index2 = original->index;
|
||
}
|
||
}
|
||
}
|
||
|
||
/* Get the original basic block. */
|
||
basic_block
|
||
get_bb_original (basic_block bb)
|
||
{
|
||
struct htab_bb_copy_original_entry *entry;
|
||
struct htab_bb_copy_original_entry key;
|
||
|
||
gcc_assert (original_copy_bb_pool);
|
||
|
||
key.index1 = bb->index;
|
||
entry = (struct htab_bb_copy_original_entry *) htab_find (bb_original, &key);
|
||
if (entry)
|
||
return BASIC_BLOCK (entry->index2);
|
||
else
|
||
return NULL;
|
||
}
|
||
|
||
/* Set copy for basic block. Do nothing when data structures are not
|
||
initialized so passes not needing this don't need to care. */
|
||
void
|
||
set_bb_copy (basic_block bb, basic_block copy)
|
||
{
|
||
if (original_copy_bb_pool)
|
||
{
|
||
struct htab_bb_copy_original_entry **slot;
|
||
struct htab_bb_copy_original_entry key;
|
||
|
||
key.index1 = bb->index;
|
||
slot =
|
||
(struct htab_bb_copy_original_entry **) htab_find_slot (bb_copy,
|
||
&key, INSERT);
|
||
if (*slot)
|
||
(*slot)->index2 = copy->index;
|
||
else
|
||
{
|
||
*slot = pool_alloc (original_copy_bb_pool);
|
||
(*slot)->index1 = bb->index;
|
||
(*slot)->index2 = copy->index;
|
||
}
|
||
}
|
||
}
|
||
|
||
/* Get the copy of basic block. */
|
||
basic_block
|
||
get_bb_copy (basic_block bb)
|
||
{
|
||
struct htab_bb_copy_original_entry *entry;
|
||
struct htab_bb_copy_original_entry key;
|
||
|
||
gcc_assert (original_copy_bb_pool);
|
||
|
||
key.index1 = bb->index;
|
||
entry = (struct htab_bb_copy_original_entry *) htab_find (bb_copy, &key);
|
||
if (entry)
|
||
return BASIC_BLOCK (entry->index2);
|
||
else
|
||
return NULL;
|
||
}
|