/* Convert a program in SSA form into Normal form.
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/* Convert a program in SSA form into Normal form.
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Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010
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Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010
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Free Software Foundation, Inc.
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Free Software Foundation, Inc.
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Contributed by Andrew Macleod <amacleod@redhat.com>
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Contributed by Andrew Macleod <amacleod@redhat.com>
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This file is part of GCC.
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This file is part of GCC.
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GCC is free software; you can redistribute it and/or modify
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GCC is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 3, or (at your option)
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the Free Software Foundation; either version 3, or (at your option)
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any later version.
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any later version.
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GCC is distributed in the hope that it will be useful,
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GCC is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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You should have received a copy of the GNU General Public License
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along with GCC; see the file COPYING3. If not see
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along with GCC; see the file COPYING3. If not see
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<http://www.gnu.org/licenses/>. */
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<http://www.gnu.org/licenses/>. */
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#include "config.h"
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#include "config.h"
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#include "system.h"
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#include "system.h"
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#include "coretypes.h"
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#include "coretypes.h"
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#include "tm.h"
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#include "tm.h"
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#include "tree.h"
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#include "tree.h"
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#include "ggc.h"
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#include "ggc.h"
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#include "basic-block.h"
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#include "basic-block.h"
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#include "diagnostic.h"
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#include "diagnostic.h"
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#include "bitmap.h"
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#include "bitmap.h"
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#include "tree-flow.h"
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#include "tree-flow.h"
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#include "timevar.h"
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#include "timevar.h"
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#include "tree-dump.h"
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#include "tree-dump.h"
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#include "tree-pass.h"
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#include "tree-pass.h"
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#include "toplev.h"
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#include "toplev.h"
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#include "expr.h"
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#include "expr.h"
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#include "ssaexpand.h"
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#include "ssaexpand.h"
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DEF_VEC_I(source_location);
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DEF_VEC_I(source_location);
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DEF_VEC_ALLOC_I(source_location,heap);
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DEF_VEC_ALLOC_I(source_location,heap);
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|
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/* Used to hold all the components required to do SSA PHI elimination.
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/* Used to hold all the components required to do SSA PHI elimination.
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The node and pred/succ list is a simple linear list of nodes and
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The node and pred/succ list is a simple linear list of nodes and
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edges represented as pairs of nodes.
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edges represented as pairs of nodes.
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|
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The predecessor and successor list: Nodes are entered in pairs, where
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The predecessor and successor list: Nodes are entered in pairs, where
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[0] ->PRED, [1]->SUCC. All the even indexes in the array represent
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[0] ->PRED, [1]->SUCC. All the even indexes in the array represent
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predecessors, all the odd elements are successors.
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predecessors, all the odd elements are successors.
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|
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Rationale:
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Rationale:
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When implemented as bitmaps, very large programs SSA->Normal times were
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When implemented as bitmaps, very large programs SSA->Normal times were
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being dominated by clearing the interference graph.
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being dominated by clearing the interference graph.
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Typically this list of edges is extremely small since it only includes
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Typically this list of edges is extremely small since it only includes
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PHI results and uses from a single edge which have not coalesced with
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PHI results and uses from a single edge which have not coalesced with
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each other. This means that no virtual PHI nodes are included, and
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each other. This means that no virtual PHI nodes are included, and
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empirical evidence suggests that the number of edges rarely exceed
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empirical evidence suggests that the number of edges rarely exceed
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3, and in a bootstrap of GCC, the maximum size encountered was 7.
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3, and in a bootstrap of GCC, the maximum size encountered was 7.
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This also limits the number of possible nodes that are involved to
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This also limits the number of possible nodes that are involved to
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rarely more than 6, and in the bootstrap of gcc, the maximum number
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rarely more than 6, and in the bootstrap of gcc, the maximum number
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of nodes encountered was 12. */
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of nodes encountered was 12. */
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typedef struct _elim_graph {
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typedef struct _elim_graph {
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/* Size of the elimination vectors. */
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/* Size of the elimination vectors. */
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int size;
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int size;
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/* List of nodes in the elimination graph. */
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/* List of nodes in the elimination graph. */
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VEC(int,heap) *nodes;
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VEC(int,heap) *nodes;
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/* The predecessor and successor edge list. */
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/* The predecessor and successor edge list. */
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VEC(int,heap) *edge_list;
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VEC(int,heap) *edge_list;
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/* Source locus on each edge */
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/* Source locus on each edge */
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VEC(source_location,heap) *edge_locus;
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VEC(source_location,heap) *edge_locus;
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/* Visited vector. */
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/* Visited vector. */
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sbitmap visited;
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sbitmap visited;
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/* Stack for visited nodes. */
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/* Stack for visited nodes. */
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VEC(int,heap) *stack;
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VEC(int,heap) *stack;
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/* The variable partition map. */
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/* The variable partition map. */
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var_map map;
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var_map map;
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/* Edge being eliminated by this graph. */
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/* Edge being eliminated by this graph. */
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edge e;
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edge e;
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/* List of constant copies to emit. These are pushed on in pairs. */
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/* List of constant copies to emit. These are pushed on in pairs. */
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VEC(int,heap) *const_dests;
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VEC(int,heap) *const_dests;
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VEC(tree,heap) *const_copies;
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VEC(tree,heap) *const_copies;
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/* Source locations for any constant copies. */
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/* Source locations for any constant copies. */
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VEC(source_location,heap) *copy_locus;
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VEC(source_location,heap) *copy_locus;
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} *elim_graph;
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} *elim_graph;
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/* For an edge E find out a good source location to associate with
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/* For an edge E find out a good source location to associate with
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instructions inserted on edge E. If E has an implicit goto set,
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instructions inserted on edge E. If E has an implicit goto set,
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use its location. Otherwise search instructions in predecessors
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use its location. Otherwise search instructions in predecessors
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of E for a location, and use that one. That makes sense because
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of E for a location, and use that one. That makes sense because
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we insert on edges for PHI nodes, and effects of PHIs happen on
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we insert on edges for PHI nodes, and effects of PHIs happen on
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the end of the predecessor conceptually. */
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the end of the predecessor conceptually. */
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static void
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static void
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set_location_for_edge (edge e)
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set_location_for_edge (edge e)
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{
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{
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if (e->goto_locus)
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if (e->goto_locus)
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{
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{
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set_curr_insn_source_location (e->goto_locus);
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set_curr_insn_source_location (e->goto_locus);
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set_curr_insn_block (e->goto_block);
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set_curr_insn_block (e->goto_block);
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}
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}
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else
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else
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{
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{
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basic_block bb = e->src;
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basic_block bb = e->src;
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gimple_stmt_iterator gsi;
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gimple_stmt_iterator gsi;
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do
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do
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{
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{
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for (gsi = gsi_last_bb (bb); !gsi_end_p (gsi); gsi_prev (&gsi))
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for (gsi = gsi_last_bb (bb); !gsi_end_p (gsi); gsi_prev (&gsi))
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{
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{
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gimple stmt = gsi_stmt (gsi);
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gimple stmt = gsi_stmt (gsi);
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if (is_gimple_debug (stmt))
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if (is_gimple_debug (stmt))
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continue;
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continue;
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if (gimple_has_location (stmt) || gimple_block (stmt))
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if (gimple_has_location (stmt) || gimple_block (stmt))
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{
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{
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set_curr_insn_source_location (gimple_location (stmt));
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set_curr_insn_source_location (gimple_location (stmt));
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set_curr_insn_block (gimple_block (stmt));
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set_curr_insn_block (gimple_block (stmt));
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return;
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return;
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}
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}
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}
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}
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/* Nothing found in this basic block. Make a half-assed attempt
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/* Nothing found in this basic block. Make a half-assed attempt
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to continue with another block. */
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to continue with another block. */
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if (single_pred_p (bb))
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if (single_pred_p (bb))
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bb = single_pred (bb);
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bb = single_pred (bb);
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else
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else
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bb = e->src;
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bb = e->src;
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}
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}
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while (bb != e->src);
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while (bb != e->src);
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}
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}
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}
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}
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/* Emit insns to copy SRC into DEST converting SRC if necessary. As
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/* Emit insns to copy SRC into DEST converting SRC if necessary. As
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SRC/DEST might be BLKmode memory locations SIZEEXP is a tree from
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SRC/DEST might be BLKmode memory locations SIZEEXP is a tree from
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which we deduce the size to copy in that case. */
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which we deduce the size to copy in that case. */
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static inline rtx
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static inline rtx
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emit_partition_copy (rtx dest, rtx src, int unsignedsrcp, tree sizeexp)
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emit_partition_copy (rtx dest, rtx src, int unsignedsrcp, tree sizeexp)
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{
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{
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rtx seq;
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rtx seq;
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start_sequence ();
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start_sequence ();
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if (GET_MODE (src) != VOIDmode && GET_MODE (src) != GET_MODE (dest))
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if (GET_MODE (src) != VOIDmode && GET_MODE (src) != GET_MODE (dest))
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src = convert_to_mode (GET_MODE (dest), src, unsignedsrcp);
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src = convert_to_mode (GET_MODE (dest), src, unsignedsrcp);
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if (GET_MODE (src) == BLKmode)
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if (GET_MODE (src) == BLKmode)
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{
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{
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gcc_assert (GET_MODE (dest) == BLKmode);
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gcc_assert (GET_MODE (dest) == BLKmode);
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emit_block_move (dest, src, expr_size (sizeexp), BLOCK_OP_NORMAL);
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emit_block_move (dest, src, expr_size (sizeexp), BLOCK_OP_NORMAL);
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}
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}
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else
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else
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emit_move_insn (dest, src);
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emit_move_insn (dest, src);
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seq = get_insns ();
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seq = get_insns ();
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end_sequence ();
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end_sequence ();
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return seq;
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return seq;
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}
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}
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/* Insert a copy instruction from partition SRC to DEST onto edge E. */
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/* Insert a copy instruction from partition SRC to DEST onto edge E. */
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static void
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static void
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insert_partition_copy_on_edge (edge e, int dest, int src, source_location locus)
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insert_partition_copy_on_edge (edge e, int dest, int src, source_location locus)
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{
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{
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tree var;
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tree var;
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rtx seq;
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rtx seq;
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if (dump_file && (dump_flags & TDF_DETAILS))
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if (dump_file && (dump_flags & TDF_DETAILS))
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{
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{
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fprintf (dump_file,
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fprintf (dump_file,
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"Inserting a partition copy on edge BB%d->BB%d :"
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"Inserting a partition copy on edge BB%d->BB%d :"
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"PART.%d = PART.%d",
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"PART.%d = PART.%d",
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e->src->index,
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e->src->index,
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e->dest->index, dest, src);
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e->dest->index, dest, src);
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fprintf (dump_file, "\n");
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fprintf (dump_file, "\n");
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}
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}
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gcc_assert (SA.partition_to_pseudo[dest]);
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gcc_assert (SA.partition_to_pseudo[dest]);
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gcc_assert (SA.partition_to_pseudo[src]);
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gcc_assert (SA.partition_to_pseudo[src]);
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set_location_for_edge (e);
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set_location_for_edge (e);
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/* If a locus is provided, override the default. */
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/* If a locus is provided, override the default. */
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if (locus)
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if (locus)
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set_curr_insn_source_location (locus);
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set_curr_insn_source_location (locus);
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var = partition_to_var (SA.map, src);
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var = partition_to_var (SA.map, src);
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seq = emit_partition_copy (SA.partition_to_pseudo[dest],
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seq = emit_partition_copy (SA.partition_to_pseudo[dest],
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SA.partition_to_pseudo[src],
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SA.partition_to_pseudo[src],
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TYPE_UNSIGNED (TREE_TYPE (var)),
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TYPE_UNSIGNED (TREE_TYPE (var)),
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var);
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var);
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insert_insn_on_edge (seq, e);
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insert_insn_on_edge (seq, e);
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}
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}
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/* Insert a copy instruction from expression SRC to partition DEST
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/* Insert a copy instruction from expression SRC to partition DEST
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onto edge E. */
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onto edge E. */
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static void
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static void
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insert_value_copy_on_edge (edge e, int dest, tree src, source_location locus)
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insert_value_copy_on_edge (edge e, int dest, tree src, source_location locus)
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{
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{
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rtx seq, x;
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rtx seq, x;
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enum machine_mode dest_mode, src_mode;
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enum machine_mode dest_mode, src_mode;
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int unsignedp;
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int unsignedp;
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tree var;
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tree var;
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|
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if (dump_file && (dump_flags & TDF_DETAILS))
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if (dump_file && (dump_flags & TDF_DETAILS))
|
{
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{
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fprintf (dump_file,
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fprintf (dump_file,
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"Inserting a value copy on edge BB%d->BB%d : PART.%d = ",
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"Inserting a value copy on edge BB%d->BB%d : PART.%d = ",
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e->src->index,
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e->src->index,
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e->dest->index, dest);
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e->dest->index, dest);
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print_generic_expr (dump_file, src, TDF_SLIM);
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print_generic_expr (dump_file, src, TDF_SLIM);
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fprintf (dump_file, "\n");
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fprintf (dump_file, "\n");
|
}
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}
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|
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gcc_assert (SA.partition_to_pseudo[dest]);
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gcc_assert (SA.partition_to_pseudo[dest]);
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|
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set_location_for_edge (e);
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set_location_for_edge (e);
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/* If a locus is provided, override the default. */
|
/* If a locus is provided, override the default. */
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if (locus)
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if (locus)
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set_curr_insn_source_location (locus);
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set_curr_insn_source_location (locus);
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|
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start_sequence ();
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start_sequence ();
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|
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var = SSA_NAME_VAR (partition_to_var (SA.map, dest));
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var = SSA_NAME_VAR (partition_to_var (SA.map, dest));
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src_mode = TYPE_MODE (TREE_TYPE (src));
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src_mode = TYPE_MODE (TREE_TYPE (src));
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dest_mode = promote_decl_mode (var, &unsignedp);
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dest_mode = promote_decl_mode (var, &unsignedp);
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gcc_assert (src_mode == TYPE_MODE (TREE_TYPE (var)));
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gcc_assert (src_mode == TYPE_MODE (TREE_TYPE (var)));
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gcc_assert (dest_mode == GET_MODE (SA.partition_to_pseudo[dest]));
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gcc_assert (dest_mode == GET_MODE (SA.partition_to_pseudo[dest]));
|
|
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if (src_mode != dest_mode)
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if (src_mode != dest_mode)
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{
|
{
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x = expand_expr (src, NULL, src_mode, EXPAND_NORMAL);
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x = expand_expr (src, NULL, src_mode, EXPAND_NORMAL);
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x = convert_modes (dest_mode, src_mode, x, unsignedp);
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x = convert_modes (dest_mode, src_mode, x, unsignedp);
|
}
|
}
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else if (src_mode == BLKmode)
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else if (src_mode == BLKmode)
|
{
|
{
|
x = SA.partition_to_pseudo[dest];
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x = SA.partition_to_pseudo[dest];
|
store_expr (src, x, 0, false);
|
store_expr (src, x, 0, false);
|
}
|
}
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else
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else
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x = expand_expr (src, SA.partition_to_pseudo[dest],
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x = expand_expr (src, SA.partition_to_pseudo[dest],
|
dest_mode, EXPAND_NORMAL);
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dest_mode, EXPAND_NORMAL);
|
|
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if (x != SA.partition_to_pseudo[dest])
|
if (x != SA.partition_to_pseudo[dest])
|
emit_move_insn (SA.partition_to_pseudo[dest], x);
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emit_move_insn (SA.partition_to_pseudo[dest], x);
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seq = get_insns ();
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seq = get_insns ();
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end_sequence ();
|
end_sequence ();
|
|
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insert_insn_on_edge (seq, e);
|
insert_insn_on_edge (seq, e);
|
}
|
}
|
|
|
/* Insert a copy instruction from RTL expression SRC to partition DEST
|
/* Insert a copy instruction from RTL expression SRC to partition DEST
|
onto edge E. */
|
onto edge E. */
|
|
|
static void
|
static void
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insert_rtx_to_part_on_edge (edge e, int dest, rtx src, int unsignedsrcp,
|
insert_rtx_to_part_on_edge (edge e, int dest, rtx src, int unsignedsrcp,
|
source_location locus)
|
source_location locus)
|
{
|
{
|
rtx seq;
|
rtx seq;
|
if (dump_file && (dump_flags & TDF_DETAILS))
|
if (dump_file && (dump_flags & TDF_DETAILS))
|
{
|
{
|
fprintf (dump_file,
|
fprintf (dump_file,
|
"Inserting a temp copy on edge BB%d->BB%d : PART.%d = ",
|
"Inserting a temp copy on edge BB%d->BB%d : PART.%d = ",
|
e->src->index,
|
e->src->index,
|
e->dest->index, dest);
|
e->dest->index, dest);
|
print_simple_rtl (dump_file, src);
|
print_simple_rtl (dump_file, src);
|
fprintf (dump_file, "\n");
|
fprintf (dump_file, "\n");
|
}
|
}
|
|
|
gcc_assert (SA.partition_to_pseudo[dest]);
|
gcc_assert (SA.partition_to_pseudo[dest]);
|
|
|
set_location_for_edge (e);
|
set_location_for_edge (e);
|
/* If a locus is provided, override the default. */
|
/* If a locus is provided, override the default. */
|
if (locus)
|
if (locus)
|
set_curr_insn_source_location (locus);
|
set_curr_insn_source_location (locus);
|
|
|
/* We give the destination as sizeexp in case src/dest are BLKmode
|
/* We give the destination as sizeexp in case src/dest are BLKmode
|
mems. Usually we give the source. As we result from SSA names
|
mems. Usually we give the source. As we result from SSA names
|
the left and right size should be the same (and no WITH_SIZE_EXPR
|
the left and right size should be the same (and no WITH_SIZE_EXPR
|
involved), so it doesn't matter. */
|
involved), so it doesn't matter. */
|
seq = emit_partition_copy (SA.partition_to_pseudo[dest],
|
seq = emit_partition_copy (SA.partition_to_pseudo[dest],
|
src, unsignedsrcp,
|
src, unsignedsrcp,
|
partition_to_var (SA.map, dest));
|
partition_to_var (SA.map, dest));
|
|
|
insert_insn_on_edge (seq, e);
|
insert_insn_on_edge (seq, e);
|
}
|
}
|
|
|
/* Insert a copy instruction from partition SRC to RTL lvalue DEST
|
/* Insert a copy instruction from partition SRC to RTL lvalue DEST
|
onto edge E. */
|
onto edge E. */
|
|
|
static void
|
static void
|
insert_part_to_rtx_on_edge (edge e, rtx dest, int src, source_location locus)
|
insert_part_to_rtx_on_edge (edge e, rtx dest, int src, source_location locus)
|
{
|
{
|
tree var;
|
tree var;
|
rtx seq;
|
rtx seq;
|
if (dump_file && (dump_flags & TDF_DETAILS))
|
if (dump_file && (dump_flags & TDF_DETAILS))
|
{
|
{
|
fprintf (dump_file,
|
fprintf (dump_file,
|
"Inserting a temp copy on edge BB%d->BB%d : ",
|
"Inserting a temp copy on edge BB%d->BB%d : ",
|
e->src->index,
|
e->src->index,
|
e->dest->index);
|
e->dest->index);
|
print_simple_rtl (dump_file, dest);
|
print_simple_rtl (dump_file, dest);
|
fprintf (dump_file, "= PART.%d\n", src);
|
fprintf (dump_file, "= PART.%d\n", src);
|
}
|
}
|
|
|
gcc_assert (SA.partition_to_pseudo[src]);
|
gcc_assert (SA.partition_to_pseudo[src]);
|
|
|
set_location_for_edge (e);
|
set_location_for_edge (e);
|
/* If a locus is provided, override the default. */
|
/* If a locus is provided, override the default. */
|
if (locus)
|
if (locus)
|
set_curr_insn_source_location (locus);
|
set_curr_insn_source_location (locus);
|
|
|
var = partition_to_var (SA.map, src);
|
var = partition_to_var (SA.map, src);
|
seq = emit_partition_copy (dest,
|
seq = emit_partition_copy (dest,
|
SA.partition_to_pseudo[src],
|
SA.partition_to_pseudo[src],
|
TYPE_UNSIGNED (TREE_TYPE (var)),
|
TYPE_UNSIGNED (TREE_TYPE (var)),
|
var);
|
var);
|
|
|
insert_insn_on_edge (seq, e);
|
insert_insn_on_edge (seq, e);
|
}
|
}
|
|
|
|
|
/* Create an elimination graph with SIZE nodes and associated data
|
/* Create an elimination graph with SIZE nodes and associated data
|
structures. */
|
structures. */
|
|
|
static elim_graph
|
static elim_graph
|
new_elim_graph (int size)
|
new_elim_graph (int size)
|
{
|
{
|
elim_graph g = (elim_graph) xmalloc (sizeof (struct _elim_graph));
|
elim_graph g = (elim_graph) xmalloc (sizeof (struct _elim_graph));
|
|
|
g->nodes = VEC_alloc (int, heap, 30);
|
g->nodes = VEC_alloc (int, heap, 30);
|
g->const_dests = VEC_alloc (int, heap, 20);
|
g->const_dests = VEC_alloc (int, heap, 20);
|
g->const_copies = VEC_alloc (tree, heap, 20);
|
g->const_copies = VEC_alloc (tree, heap, 20);
|
g->copy_locus = VEC_alloc (source_location, heap, 10);
|
g->copy_locus = VEC_alloc (source_location, heap, 10);
|
g->edge_list = VEC_alloc (int, heap, 20);
|
g->edge_list = VEC_alloc (int, heap, 20);
|
g->edge_locus = VEC_alloc (source_location, heap, 10);
|
g->edge_locus = VEC_alloc (source_location, heap, 10);
|
g->stack = VEC_alloc (int, heap, 30);
|
g->stack = VEC_alloc (int, heap, 30);
|
|
|
g->visited = sbitmap_alloc (size);
|
g->visited = sbitmap_alloc (size);
|
|
|
return g;
|
return g;
|
}
|
}
|
|
|
|
|
/* Empty elimination graph G. */
|
/* Empty elimination graph G. */
|
|
|
static inline void
|
static inline void
|
clear_elim_graph (elim_graph g)
|
clear_elim_graph (elim_graph g)
|
{
|
{
|
VEC_truncate (int, g->nodes, 0);
|
VEC_truncate (int, g->nodes, 0);
|
VEC_truncate (int, g->edge_list, 0);
|
VEC_truncate (int, g->edge_list, 0);
|
VEC_truncate (source_location, g->edge_locus, 0);
|
VEC_truncate (source_location, g->edge_locus, 0);
|
}
|
}
|
|
|
|
|
/* Delete elimination graph G. */
|
/* Delete elimination graph G. */
|
|
|
static inline void
|
static inline void
|
delete_elim_graph (elim_graph g)
|
delete_elim_graph (elim_graph g)
|
{
|
{
|
sbitmap_free (g->visited);
|
sbitmap_free (g->visited);
|
VEC_free (int, heap, g->stack);
|
VEC_free (int, heap, g->stack);
|
VEC_free (int, heap, g->edge_list);
|
VEC_free (int, heap, g->edge_list);
|
VEC_free (tree, heap, g->const_copies);
|
VEC_free (tree, heap, g->const_copies);
|
VEC_free (int, heap, g->const_dests);
|
VEC_free (int, heap, g->const_dests);
|
VEC_free (int, heap, g->nodes);
|
VEC_free (int, heap, g->nodes);
|
VEC_free (source_location, heap, g->copy_locus);
|
VEC_free (source_location, heap, g->copy_locus);
|
VEC_free (source_location, heap, g->edge_locus);
|
VEC_free (source_location, heap, g->edge_locus);
|
|
|
free (g);
|
free (g);
|
}
|
}
|
|
|
|
|
/* Return the number of nodes in graph G. */
|
/* Return the number of nodes in graph G. */
|
|
|
static inline int
|
static inline int
|
elim_graph_size (elim_graph g)
|
elim_graph_size (elim_graph g)
|
{
|
{
|
return VEC_length (int, g->nodes);
|
return VEC_length (int, g->nodes);
|
}
|
}
|
|
|
|
|
/* Add NODE to graph G, if it doesn't exist already. */
|
/* Add NODE to graph G, if it doesn't exist already. */
|
|
|
static inline void
|
static inline void
|
elim_graph_add_node (elim_graph g, int node)
|
elim_graph_add_node (elim_graph g, int node)
|
{
|
{
|
int x;
|
int x;
|
int t;
|
int t;
|
|
|
for (x = 0; VEC_iterate (int, g->nodes, x, t); x++)
|
for (x = 0; VEC_iterate (int, g->nodes, x, t); x++)
|
if (t == node)
|
if (t == node)
|
return;
|
return;
|
VEC_safe_push (int, heap, g->nodes, node);
|
VEC_safe_push (int, heap, g->nodes, node);
|
}
|
}
|
|
|
|
|
/* Add the edge PRED->SUCC to graph G. */
|
/* Add the edge PRED->SUCC to graph G. */
|
|
|
static inline void
|
static inline void
|
elim_graph_add_edge (elim_graph g, int pred, int succ, source_location locus)
|
elim_graph_add_edge (elim_graph g, int pred, int succ, source_location locus)
|
{
|
{
|
VEC_safe_push (int, heap, g->edge_list, pred);
|
VEC_safe_push (int, heap, g->edge_list, pred);
|
VEC_safe_push (int, heap, g->edge_list, succ);
|
VEC_safe_push (int, heap, g->edge_list, succ);
|
VEC_safe_push (source_location, heap, g->edge_locus, locus);
|
VEC_safe_push (source_location, heap, g->edge_locus, locus);
|
}
|
}
|
|
|
|
|
/* Remove an edge from graph G for which NODE is the predecessor, and
|
/* Remove an edge from graph G for which NODE is the predecessor, and
|
return the successor node. -1 is returned if there is no such edge. */
|
return the successor node. -1 is returned if there is no such edge. */
|
|
|
static inline int
|
static inline int
|
elim_graph_remove_succ_edge (elim_graph g, int node, source_location *locus)
|
elim_graph_remove_succ_edge (elim_graph g, int node, source_location *locus)
|
{
|
{
|
int y;
|
int y;
|
unsigned x;
|
unsigned x;
|
for (x = 0; x < VEC_length (int, g->edge_list); x += 2)
|
for (x = 0; x < VEC_length (int, g->edge_list); x += 2)
|
if (VEC_index (int, g->edge_list, x) == node)
|
if (VEC_index (int, g->edge_list, x) == node)
|
{
|
{
|
VEC_replace (int, g->edge_list, x, -1);
|
VEC_replace (int, g->edge_list, x, -1);
|
y = VEC_index (int, g->edge_list, x + 1);
|
y = VEC_index (int, g->edge_list, x + 1);
|
VEC_replace (int, g->edge_list, x + 1, -1);
|
VEC_replace (int, g->edge_list, x + 1, -1);
|
*locus = VEC_index (source_location, g->edge_locus, x / 2);
|
*locus = VEC_index (source_location, g->edge_locus, x / 2);
|
VEC_replace (source_location, g->edge_locus, x / 2, UNKNOWN_LOCATION);
|
VEC_replace (source_location, g->edge_locus, x / 2, UNKNOWN_LOCATION);
|
return y;
|
return y;
|
}
|
}
|
*locus = UNKNOWN_LOCATION;
|
*locus = UNKNOWN_LOCATION;
|
return -1;
|
return -1;
|
}
|
}
|
|
|
|
|
/* Find all the nodes in GRAPH which are successors to NODE in the
|
/* Find all the nodes in GRAPH which are successors to NODE in the
|
edge list. VAR will hold the partition number found. CODE is the
|
edge list. VAR will hold the partition number found. CODE is the
|
code fragment executed for every node found. */
|
code fragment executed for every node found. */
|
|
|
#define FOR_EACH_ELIM_GRAPH_SUCC(GRAPH, NODE, VAR, LOCUS, CODE) \
|
#define FOR_EACH_ELIM_GRAPH_SUCC(GRAPH, NODE, VAR, LOCUS, CODE) \
|
do { \
|
do { \
|
unsigned x_; \
|
unsigned x_; \
|
int y_; \
|
int y_; \
|
for (x_ = 0; x_ < VEC_length (int, (GRAPH)->edge_list); x_ += 2) \
|
for (x_ = 0; x_ < VEC_length (int, (GRAPH)->edge_list); x_ += 2) \
|
{ \
|
{ \
|
y_ = VEC_index (int, (GRAPH)->edge_list, x_); \
|
y_ = VEC_index (int, (GRAPH)->edge_list, x_); \
|
if (y_ != (NODE)) \
|
if (y_ != (NODE)) \
|
continue; \
|
continue; \
|
(VAR) = VEC_index (int, (GRAPH)->edge_list, x_ + 1); \
|
(VAR) = VEC_index (int, (GRAPH)->edge_list, x_ + 1); \
|
(LOCUS) = VEC_index (source_location, (GRAPH)->edge_locus, x_ / 2); \
|
(LOCUS) = VEC_index (source_location, (GRAPH)->edge_locus, x_ / 2); \
|
CODE; \
|
CODE; \
|
} \
|
} \
|
} while (0)
|
} while (0)
|
|
|
|
|
/* Find all the nodes which are predecessors of NODE in the edge list for
|
/* Find all the nodes which are predecessors of NODE in the edge list for
|
GRAPH. VAR will hold the partition number found. CODE is the
|
GRAPH. VAR will hold the partition number found. CODE is the
|
code fragment executed for every node found. */
|
code fragment executed for every node found. */
|
|
|
#define FOR_EACH_ELIM_GRAPH_PRED(GRAPH, NODE, VAR, LOCUS, CODE) \
|
#define FOR_EACH_ELIM_GRAPH_PRED(GRAPH, NODE, VAR, LOCUS, CODE) \
|
do { \
|
do { \
|
unsigned x_; \
|
unsigned x_; \
|
int y_; \
|
int y_; \
|
for (x_ = 0; x_ < VEC_length (int, (GRAPH)->edge_list); x_ += 2) \
|
for (x_ = 0; x_ < VEC_length (int, (GRAPH)->edge_list); x_ += 2) \
|
{ \
|
{ \
|
y_ = VEC_index (int, (GRAPH)->edge_list, x_ + 1); \
|
y_ = VEC_index (int, (GRAPH)->edge_list, x_ + 1); \
|
if (y_ != (NODE)) \
|
if (y_ != (NODE)) \
|
continue; \
|
continue; \
|
(VAR) = VEC_index (int, (GRAPH)->edge_list, x_); \
|
(VAR) = VEC_index (int, (GRAPH)->edge_list, x_); \
|
(LOCUS) = VEC_index (source_location, (GRAPH)->edge_locus, x_ / 2); \
|
(LOCUS) = VEC_index (source_location, (GRAPH)->edge_locus, x_ / 2); \
|
CODE; \
|
CODE; \
|
} \
|
} \
|
} while (0)
|
} while (0)
|
|
|
|
|
/* Add T to elimination graph G. */
|
/* Add T to elimination graph G. */
|
|
|
static inline void
|
static inline void
|
eliminate_name (elim_graph g, int T)
|
eliminate_name (elim_graph g, int T)
|
{
|
{
|
elim_graph_add_node (g, T);
|
elim_graph_add_node (g, T);
|
}
|
}
|
|
|
|
|
/* Build elimination graph G for basic block BB on incoming PHI edge
|
/* Build elimination graph G for basic block BB on incoming PHI edge
|
G->e. */
|
G->e. */
|
|
|
static void
|
static void
|
eliminate_build (elim_graph g)
|
eliminate_build (elim_graph g)
|
{
|
{
|
tree Ti;
|
tree Ti;
|
int p0, pi;
|
int p0, pi;
|
gimple_stmt_iterator gsi;
|
gimple_stmt_iterator gsi;
|
|
|
clear_elim_graph (g);
|
clear_elim_graph (g);
|
|
|
for (gsi = gsi_start_phis (g->e->dest); !gsi_end_p (gsi); gsi_next (&gsi))
|
for (gsi = gsi_start_phis (g->e->dest); !gsi_end_p (gsi); gsi_next (&gsi))
|
{
|
{
|
gimple phi = gsi_stmt (gsi);
|
gimple phi = gsi_stmt (gsi);
|
source_location locus;
|
source_location locus;
|
|
|
p0 = var_to_partition (g->map, gimple_phi_result (phi));
|
p0 = var_to_partition (g->map, gimple_phi_result (phi));
|
/* Ignore results which are not in partitions. */
|
/* Ignore results which are not in partitions. */
|
if (p0 == NO_PARTITION)
|
if (p0 == NO_PARTITION)
|
continue;
|
continue;
|
|
|
Ti = PHI_ARG_DEF (phi, g->e->dest_idx);
|
Ti = PHI_ARG_DEF (phi, g->e->dest_idx);
|
locus = gimple_phi_arg_location_from_edge (phi, g->e);
|
locus = gimple_phi_arg_location_from_edge (phi, g->e);
|
|
|
/* If this argument is a constant, or a SSA_NAME which is being
|
/* If this argument is a constant, or a SSA_NAME which is being
|
left in SSA form, just queue a copy to be emitted on this
|
left in SSA form, just queue a copy to be emitted on this
|
edge. */
|
edge. */
|
if (!phi_ssa_name_p (Ti)
|
if (!phi_ssa_name_p (Ti)
|
|| (TREE_CODE (Ti) == SSA_NAME
|
|| (TREE_CODE (Ti) == SSA_NAME
|
&& var_to_partition (g->map, Ti) == NO_PARTITION))
|
&& var_to_partition (g->map, Ti) == NO_PARTITION))
|
{
|
{
|
/* Save constant copies until all other copies have been emitted
|
/* Save constant copies until all other copies have been emitted
|
on this edge. */
|
on this edge. */
|
VEC_safe_push (int, heap, g->const_dests, p0);
|
VEC_safe_push (int, heap, g->const_dests, p0);
|
VEC_safe_push (tree, heap, g->const_copies, Ti);
|
VEC_safe_push (tree, heap, g->const_copies, Ti);
|
VEC_safe_push (source_location, heap, g->copy_locus, locus);
|
VEC_safe_push (source_location, heap, g->copy_locus, locus);
|
}
|
}
|
else
|
else
|
{
|
{
|
pi = var_to_partition (g->map, Ti);
|
pi = var_to_partition (g->map, Ti);
|
if (p0 != pi)
|
if (p0 != pi)
|
{
|
{
|
eliminate_name (g, p0);
|
eliminate_name (g, p0);
|
eliminate_name (g, pi);
|
eliminate_name (g, pi);
|
elim_graph_add_edge (g, p0, pi, locus);
|
elim_graph_add_edge (g, p0, pi, locus);
|
}
|
}
|
}
|
}
|
}
|
}
|
}
|
}
|
|
|
|
|
/* Push successors of T onto the elimination stack for G. */
|
/* Push successors of T onto the elimination stack for G. */
|
|
|
static void
|
static void
|
elim_forward (elim_graph g, int T)
|
elim_forward (elim_graph g, int T)
|
{
|
{
|
int S;
|
int S;
|
source_location locus;
|
source_location locus;
|
|
|
SET_BIT (g->visited, T);
|
SET_BIT (g->visited, T);
|
FOR_EACH_ELIM_GRAPH_SUCC (g, T, S, locus,
|
FOR_EACH_ELIM_GRAPH_SUCC (g, T, S, locus,
|
{
|
{
|
if (!TEST_BIT (g->visited, S))
|
if (!TEST_BIT (g->visited, S))
|
elim_forward (g, S);
|
elim_forward (g, S);
|
});
|
});
|
VEC_safe_push (int, heap, g->stack, T);
|
VEC_safe_push (int, heap, g->stack, T);
|
}
|
}
|
|
|
|
|
/* Return 1 if there unvisited predecessors of T in graph G. */
|
/* Return 1 if there unvisited predecessors of T in graph G. */
|
|
|
static int
|
static int
|
elim_unvisited_predecessor (elim_graph g, int T)
|
elim_unvisited_predecessor (elim_graph g, int T)
|
{
|
{
|
int P;
|
int P;
|
source_location locus;
|
source_location locus;
|
|
|
FOR_EACH_ELIM_GRAPH_PRED (g, T, P, locus,
|
FOR_EACH_ELIM_GRAPH_PRED (g, T, P, locus,
|
{
|
{
|
if (!TEST_BIT (g->visited, P))
|
if (!TEST_BIT (g->visited, P))
|
return 1;
|
return 1;
|
});
|
});
|
return 0;
|
return 0;
|
}
|
}
|
|
|
/* Process predecessors first, and insert a copy. */
|
/* Process predecessors first, and insert a copy. */
|
|
|
static void
|
static void
|
elim_backward (elim_graph g, int T)
|
elim_backward (elim_graph g, int T)
|
{
|
{
|
int P;
|
int P;
|
source_location locus;
|
source_location locus;
|
|
|
SET_BIT (g->visited, T);
|
SET_BIT (g->visited, T);
|
FOR_EACH_ELIM_GRAPH_PRED (g, T, P, locus,
|
FOR_EACH_ELIM_GRAPH_PRED (g, T, P, locus,
|
{
|
{
|
if (!TEST_BIT (g->visited, P))
|
if (!TEST_BIT (g->visited, P))
|
{
|
{
|
elim_backward (g, P);
|
elim_backward (g, P);
|
insert_partition_copy_on_edge (g->e, P, T, locus);
|
insert_partition_copy_on_edge (g->e, P, T, locus);
|
}
|
}
|
});
|
});
|
}
|
}
|
|
|
/* Allocate a new pseudo register usable for storing values sitting
|
/* Allocate a new pseudo register usable for storing values sitting
|
in NAME (a decl or SSA name), i.e. with matching mode and attributes. */
|
in NAME (a decl or SSA name), i.e. with matching mode and attributes. */
|
|
|
static rtx
|
static rtx
|
get_temp_reg (tree name)
|
get_temp_reg (tree name)
|
{
|
{
|
tree var = TREE_CODE (name) == SSA_NAME ? SSA_NAME_VAR (name) : name;
|
tree var = TREE_CODE (name) == SSA_NAME ? SSA_NAME_VAR (name) : name;
|
tree type = TREE_TYPE (var);
|
tree type = TREE_TYPE (var);
|
int unsignedp;
|
int unsignedp;
|
enum machine_mode reg_mode = promote_decl_mode (var, &unsignedp);
|
enum machine_mode reg_mode = promote_decl_mode (var, &unsignedp);
|
rtx x = gen_reg_rtx (reg_mode);
|
rtx x = gen_reg_rtx (reg_mode);
|
if (POINTER_TYPE_P (type))
|
if (POINTER_TYPE_P (type))
|
mark_reg_pointer (x, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (var))));
|
mark_reg_pointer (x, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (var))));
|
return x;
|
return x;
|
}
|
}
|
|
|
/* Insert required copies for T in graph G. Check for a strongly connected
|
/* Insert required copies for T in graph G. Check for a strongly connected
|
region, and create a temporary to break the cycle if one is found. */
|
region, and create a temporary to break the cycle if one is found. */
|
|
|
static void
|
static void
|
elim_create (elim_graph g, int T)
|
elim_create (elim_graph g, int T)
|
{
|
{
|
int P, S;
|
int P, S;
|
source_location locus;
|
source_location locus;
|
|
|
if (elim_unvisited_predecessor (g, T))
|
if (elim_unvisited_predecessor (g, T))
|
{
|
{
|
tree var = partition_to_var (g->map, T);
|
tree var = partition_to_var (g->map, T);
|
rtx U = get_temp_reg (var);
|
rtx U = get_temp_reg (var);
|
int unsignedsrcp = TYPE_UNSIGNED (TREE_TYPE (var));
|
int unsignedsrcp = TYPE_UNSIGNED (TREE_TYPE (var));
|
|
|
insert_part_to_rtx_on_edge (g->e, U, T, UNKNOWN_LOCATION);
|
insert_part_to_rtx_on_edge (g->e, U, T, UNKNOWN_LOCATION);
|
FOR_EACH_ELIM_GRAPH_PRED (g, T, P, locus,
|
FOR_EACH_ELIM_GRAPH_PRED (g, T, P, locus,
|
{
|
{
|
if (!TEST_BIT (g->visited, P))
|
if (!TEST_BIT (g->visited, P))
|
{
|
{
|
elim_backward (g, P);
|
elim_backward (g, P);
|
insert_rtx_to_part_on_edge (g->e, P, U, unsignedsrcp, locus);
|
insert_rtx_to_part_on_edge (g->e, P, U, unsignedsrcp, locus);
|
}
|
}
|
});
|
});
|
}
|
}
|
else
|
else
|
{
|
{
|
S = elim_graph_remove_succ_edge (g, T, &locus);
|
S = elim_graph_remove_succ_edge (g, T, &locus);
|
if (S != -1)
|
if (S != -1)
|
{
|
{
|
SET_BIT (g->visited, T);
|
SET_BIT (g->visited, T);
|
insert_partition_copy_on_edge (g->e, T, S, locus);
|
insert_partition_copy_on_edge (g->e, T, S, locus);
|
}
|
}
|
}
|
}
|
}
|
}
|
|
|
|
|
/* Eliminate all the phi nodes on edge E in graph G. */
|
/* Eliminate all the phi nodes on edge E in graph G. */
|
|
|
static void
|
static void
|
eliminate_phi (edge e, elim_graph g)
|
eliminate_phi (edge e, elim_graph g)
|
{
|
{
|
int x;
|
int x;
|
|
|
gcc_assert (VEC_length (tree, g->const_copies) == 0);
|
gcc_assert (VEC_length (tree, g->const_copies) == 0);
|
gcc_assert (VEC_length (source_location, g->copy_locus) == 0);
|
gcc_assert (VEC_length (source_location, g->copy_locus) == 0);
|
|
|
/* Abnormal edges already have everything coalesced. */
|
/* Abnormal edges already have everything coalesced. */
|
if (e->flags & EDGE_ABNORMAL)
|
if (e->flags & EDGE_ABNORMAL)
|
return;
|
return;
|
|
|
g->e = e;
|
g->e = e;
|
|
|
eliminate_build (g);
|
eliminate_build (g);
|
|
|
if (elim_graph_size (g) != 0)
|
if (elim_graph_size (g) != 0)
|
{
|
{
|
int part;
|
int part;
|
|
|
sbitmap_zero (g->visited);
|
sbitmap_zero (g->visited);
|
VEC_truncate (int, g->stack, 0);
|
VEC_truncate (int, g->stack, 0);
|
|
|
for (x = 0; VEC_iterate (int, g->nodes, x, part); x++)
|
for (x = 0; VEC_iterate (int, g->nodes, x, part); x++)
|
{
|
{
|
if (!TEST_BIT (g->visited, part))
|
if (!TEST_BIT (g->visited, part))
|
elim_forward (g, part);
|
elim_forward (g, part);
|
}
|
}
|
|
|
sbitmap_zero (g->visited);
|
sbitmap_zero (g->visited);
|
while (VEC_length (int, g->stack) > 0)
|
while (VEC_length (int, g->stack) > 0)
|
{
|
{
|
x = VEC_pop (int, g->stack);
|
x = VEC_pop (int, g->stack);
|
if (!TEST_BIT (g->visited, x))
|
if (!TEST_BIT (g->visited, x))
|
elim_create (g, x);
|
elim_create (g, x);
|
}
|
}
|
}
|
}
|
|
|
/* If there are any pending constant copies, issue them now. */
|
/* If there are any pending constant copies, issue them now. */
|
while (VEC_length (tree, g->const_copies) > 0)
|
while (VEC_length (tree, g->const_copies) > 0)
|
{
|
{
|
int dest;
|
int dest;
|
tree src;
|
tree src;
|
source_location locus;
|
source_location locus;
|
|
|
src = VEC_pop (tree, g->const_copies);
|
src = VEC_pop (tree, g->const_copies);
|
dest = VEC_pop (int, g->const_dests);
|
dest = VEC_pop (int, g->const_dests);
|
locus = VEC_pop (source_location, g->copy_locus);
|
locus = VEC_pop (source_location, g->copy_locus);
|
insert_value_copy_on_edge (e, dest, src, locus);
|
insert_value_copy_on_edge (e, dest, src, locus);
|
}
|
}
|
}
|
}
|
|
|
|
|
/* Remove each argument from PHI. If an arg was the last use of an SSA_NAME,
|
/* Remove each argument from PHI. If an arg was the last use of an SSA_NAME,
|
check to see if this allows another PHI node to be removed. */
|
check to see if this allows another PHI node to be removed. */
|
|
|
static void
|
static void
|
remove_gimple_phi_args (gimple phi)
|
remove_gimple_phi_args (gimple phi)
|
{
|
{
|
use_operand_p arg_p;
|
use_operand_p arg_p;
|
ssa_op_iter iter;
|
ssa_op_iter iter;
|
|
|
if (dump_file && (dump_flags & TDF_DETAILS))
|
if (dump_file && (dump_flags & TDF_DETAILS))
|
{
|
{
|
fprintf (dump_file, "Removing Dead PHI definition: ");
|
fprintf (dump_file, "Removing Dead PHI definition: ");
|
print_gimple_stmt (dump_file, phi, 0, TDF_SLIM);
|
print_gimple_stmt (dump_file, phi, 0, TDF_SLIM);
|
}
|
}
|
|
|
FOR_EACH_PHI_ARG (arg_p, phi, iter, SSA_OP_USE)
|
FOR_EACH_PHI_ARG (arg_p, phi, iter, SSA_OP_USE)
|
{
|
{
|
tree arg = USE_FROM_PTR (arg_p);
|
tree arg = USE_FROM_PTR (arg_p);
|
if (TREE_CODE (arg) == SSA_NAME)
|
if (TREE_CODE (arg) == SSA_NAME)
|
{
|
{
|
/* Remove the reference to the existing argument. */
|
/* Remove the reference to the existing argument. */
|
SET_USE (arg_p, NULL_TREE);
|
SET_USE (arg_p, NULL_TREE);
|
if (has_zero_uses (arg))
|
if (has_zero_uses (arg))
|
{
|
{
|
gimple stmt;
|
gimple stmt;
|
gimple_stmt_iterator gsi;
|
gimple_stmt_iterator gsi;
|
|
|
stmt = SSA_NAME_DEF_STMT (arg);
|
stmt = SSA_NAME_DEF_STMT (arg);
|
|
|
/* Also remove the def if it is a PHI node. */
|
/* Also remove the def if it is a PHI node. */
|
if (gimple_code (stmt) == GIMPLE_PHI)
|
if (gimple_code (stmt) == GIMPLE_PHI)
|
{
|
{
|
remove_gimple_phi_args (stmt);
|
remove_gimple_phi_args (stmt);
|
gsi = gsi_for_stmt (stmt);
|
gsi = gsi_for_stmt (stmt);
|
remove_phi_node (&gsi, true);
|
remove_phi_node (&gsi, true);
|
}
|
}
|
|
|
}
|
}
|
}
|
}
|
}
|
}
|
}
|
}
|
|
|
/* Remove any PHI node which is a virtual PHI, or a PHI with no uses. */
|
/* Remove any PHI node which is a virtual PHI, or a PHI with no uses. */
|
|
|
static void
|
static void
|
eliminate_useless_phis (void)
|
eliminate_useless_phis (void)
|
{
|
{
|
basic_block bb;
|
basic_block bb;
|
gimple_stmt_iterator gsi;
|
gimple_stmt_iterator gsi;
|
tree result;
|
tree result;
|
|
|
FOR_EACH_BB (bb)
|
FOR_EACH_BB (bb)
|
{
|
{
|
for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); )
|
for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); )
|
{
|
{
|
gimple phi = gsi_stmt (gsi);
|
gimple phi = gsi_stmt (gsi);
|
result = gimple_phi_result (phi);
|
result = gimple_phi_result (phi);
|
if (!is_gimple_reg (SSA_NAME_VAR (result)))
|
if (!is_gimple_reg (SSA_NAME_VAR (result)))
|
{
|
{
|
#ifdef ENABLE_CHECKING
|
#ifdef ENABLE_CHECKING
|
size_t i;
|
size_t i;
|
/* There should be no arguments which are not virtual, or the
|
/* There should be no arguments which are not virtual, or the
|
results will be incorrect. */
|
results will be incorrect. */
|
for (i = 0; i < gimple_phi_num_args (phi); i++)
|
for (i = 0; i < gimple_phi_num_args (phi); i++)
|
{
|
{
|
tree arg = PHI_ARG_DEF (phi, i);
|
tree arg = PHI_ARG_DEF (phi, i);
|
if (TREE_CODE (arg) == SSA_NAME
|
if (TREE_CODE (arg) == SSA_NAME
|
&& is_gimple_reg (SSA_NAME_VAR (arg)))
|
&& is_gimple_reg (SSA_NAME_VAR (arg)))
|
{
|
{
|
fprintf (stderr, "Argument of PHI is not virtual (");
|
fprintf (stderr, "Argument of PHI is not virtual (");
|
print_generic_expr (stderr, arg, TDF_SLIM);
|
print_generic_expr (stderr, arg, TDF_SLIM);
|
fprintf (stderr, "), but the result is :");
|
fprintf (stderr, "), but the result is :");
|
print_gimple_stmt (stderr, phi, 0, TDF_SLIM);
|
print_gimple_stmt (stderr, phi, 0, TDF_SLIM);
|
internal_error ("SSA corruption");
|
internal_error ("SSA corruption");
|
}
|
}
|
}
|
}
|
#endif
|
#endif
|
remove_phi_node (&gsi, true);
|
remove_phi_node (&gsi, true);
|
}
|
}
|
else
|
else
|
{
|
{
|
/* Also remove real PHIs with no uses. */
|
/* Also remove real PHIs with no uses. */
|
if (has_zero_uses (result))
|
if (has_zero_uses (result))
|
{
|
{
|
remove_gimple_phi_args (phi);
|
remove_gimple_phi_args (phi);
|
remove_phi_node (&gsi, true);
|
remove_phi_node (&gsi, true);
|
}
|
}
|
else
|
else
|
gsi_next (&gsi);
|
gsi_next (&gsi);
|
}
|
}
|
}
|
}
|
}
|
}
|
}
|
}
|
|
|
|
|
/* This function will rewrite the current program using the variable mapping
|
/* This function will rewrite the current program using the variable mapping
|
found in MAP. If the replacement vector VALUES is provided, any
|
found in MAP. If the replacement vector VALUES is provided, any
|
occurrences of partitions with non-null entries in the vector will be
|
occurrences of partitions with non-null entries in the vector will be
|
replaced with the expression in the vector instead of its mapped
|
replaced with the expression in the vector instead of its mapped
|
variable. */
|
variable. */
|
|
|
static void
|
static void
|
rewrite_trees (var_map map ATTRIBUTE_UNUSED)
|
rewrite_trees (var_map map ATTRIBUTE_UNUSED)
|
{
|
{
|
#ifdef ENABLE_CHECKING
|
#ifdef ENABLE_CHECKING
|
basic_block bb;
|
basic_block bb;
|
/* Search for PHIs where the destination has no partition, but one
|
/* Search for PHIs where the destination has no partition, but one
|
or more arguments has a partition. This should not happen and can
|
or more arguments has a partition. This should not happen and can
|
create incorrect code. */
|
create incorrect code. */
|
FOR_EACH_BB (bb)
|
FOR_EACH_BB (bb)
|
{
|
{
|
gimple_stmt_iterator gsi;
|
gimple_stmt_iterator gsi;
|
for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
|
for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
|
{
|
{
|
gimple phi = gsi_stmt (gsi);
|
gimple phi = gsi_stmt (gsi);
|
tree T0 = var_to_partition_to_var (map, gimple_phi_result (phi));
|
tree T0 = var_to_partition_to_var (map, gimple_phi_result (phi));
|
if (T0 == NULL_TREE)
|
if (T0 == NULL_TREE)
|
{
|
{
|
size_t i;
|
size_t i;
|
for (i = 0; i < gimple_phi_num_args (phi); i++)
|
for (i = 0; i < gimple_phi_num_args (phi); i++)
|
{
|
{
|
tree arg = PHI_ARG_DEF (phi, i);
|
tree arg = PHI_ARG_DEF (phi, i);
|
|
|
if (TREE_CODE (arg) == SSA_NAME
|
if (TREE_CODE (arg) == SSA_NAME
|
&& var_to_partition (map, arg) != NO_PARTITION)
|
&& var_to_partition (map, arg) != NO_PARTITION)
|
{
|
{
|
fprintf (stderr, "Argument of PHI is in a partition :(");
|
fprintf (stderr, "Argument of PHI is in a partition :(");
|
print_generic_expr (stderr, arg, TDF_SLIM);
|
print_generic_expr (stderr, arg, TDF_SLIM);
|
fprintf (stderr, "), but the result is not :");
|
fprintf (stderr, "), but the result is not :");
|
print_gimple_stmt (stderr, phi, 0, TDF_SLIM);
|
print_gimple_stmt (stderr, phi, 0, TDF_SLIM);
|
internal_error ("SSA corruption");
|
internal_error ("SSA corruption");
|
}
|
}
|
}
|
}
|
}
|
}
|
}
|
}
|
}
|
}
|
#endif
|
#endif
|
}
|
}
|
|
|
/* Given the out-of-ssa info object SA (with prepared partitions)
|
/* Given the out-of-ssa info object SA (with prepared partitions)
|
eliminate all phi nodes in all basic blocks. Afterwards no
|
eliminate all phi nodes in all basic blocks. Afterwards no
|
basic block will have phi nodes anymore and there are possibly
|
basic block will have phi nodes anymore and there are possibly
|
some RTL instructions inserted on edges. */
|
some RTL instructions inserted on edges. */
|
|
|
void
|
void
|
expand_phi_nodes (struct ssaexpand *sa)
|
expand_phi_nodes (struct ssaexpand *sa)
|
{
|
{
|
basic_block bb;
|
basic_block bb;
|
elim_graph g = new_elim_graph (sa->map->num_partitions);
|
elim_graph g = new_elim_graph (sa->map->num_partitions);
|
g->map = sa->map;
|
g->map = sa->map;
|
|
|
FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR->next_bb, EXIT_BLOCK_PTR, next_bb)
|
FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR->next_bb, EXIT_BLOCK_PTR, next_bb)
|
if (!gimple_seq_empty_p (phi_nodes (bb)))
|
if (!gimple_seq_empty_p (phi_nodes (bb)))
|
{
|
{
|
edge e;
|
edge e;
|
edge_iterator ei;
|
edge_iterator ei;
|
FOR_EACH_EDGE (e, ei, bb->preds)
|
FOR_EACH_EDGE (e, ei, bb->preds)
|
eliminate_phi (e, g);
|
eliminate_phi (e, g);
|
set_phi_nodes (bb, NULL);
|
set_phi_nodes (bb, NULL);
|
/* We can't redirect EH edges in RTL land, so we need to do this
|
/* We can't redirect EH edges in RTL land, so we need to do this
|
here. Redirection happens only when splitting is necessary,
|
here. Redirection happens only when splitting is necessary,
|
which it is only for critical edges, normally. For EH edges
|
which it is only for critical edges, normally. For EH edges
|
it might also be necessary when the successor has more than
|
it might also be necessary when the successor has more than
|
one predecessor. In that case the edge is either required to
|
one predecessor. In that case the edge is either required to
|
be fallthru (which EH edges aren't), or the predecessor needs
|
be fallthru (which EH edges aren't), or the predecessor needs
|
to end with a jump (which again, isn't the case with EH edges).
|
to end with a jump (which again, isn't the case with EH edges).
|
Hence, split all EH edges on which we inserted instructions
|
Hence, split all EH edges on which we inserted instructions
|
and whose successor has multiple predecessors. */
|
and whose successor has multiple predecessors. */
|
for (ei = ei_start (bb->preds); (e = ei_safe_edge (ei)); )
|
for (ei = ei_start (bb->preds); (e = ei_safe_edge (ei)); )
|
{
|
{
|
if (e->insns.r && (e->flags & EDGE_EH)
|
if (e->insns.r && (e->flags & EDGE_EH)
|
&& !single_pred_p (e->dest))
|
&& !single_pred_p (e->dest))
|
{
|
{
|
rtx insns = e->insns.r;
|
rtx insns = e->insns.r;
|
basic_block bb;
|
basic_block bb;
|
e->insns.r = NULL_RTX;
|
e->insns.r = NULL_RTX;
|
bb = split_edge (e);
|
bb = split_edge (e);
|
single_pred_edge (bb)->insns.r = insns;
|
single_pred_edge (bb)->insns.r = insns;
|
}
|
}
|
else
|
else
|
ei_next (&ei);
|
ei_next (&ei);
|
}
|
}
|
}
|
}
|
|
|
delete_elim_graph (g);
|
delete_elim_graph (g);
|
}
|
}
|
|
|
|
|
/* Remove the ssa-names in the current function and translate them into normal
|
/* Remove the ssa-names in the current function and translate them into normal
|
compiler variables. PERFORM_TER is true if Temporary Expression Replacement
|
compiler variables. PERFORM_TER is true if Temporary Expression Replacement
|
should also be used. */
|
should also be used. */
|
|
|
static void
|
static void
|
remove_ssa_form (bool perform_ter, struct ssaexpand *sa)
|
remove_ssa_form (bool perform_ter, struct ssaexpand *sa)
|
{
|
{
|
bitmap values = NULL;
|
bitmap values = NULL;
|
var_map map;
|
var_map map;
|
unsigned i;
|
unsigned i;
|
|
|
map = coalesce_ssa_name ();
|
map = coalesce_ssa_name ();
|
|
|
/* Return to viewing the variable list as just all reference variables after
|
/* Return to viewing the variable list as just all reference variables after
|
coalescing has been performed. */
|
coalescing has been performed. */
|
partition_view_normal (map, false);
|
partition_view_normal (map, false);
|
|
|
if (dump_file && (dump_flags & TDF_DETAILS))
|
if (dump_file && (dump_flags & TDF_DETAILS))
|
{
|
{
|
fprintf (dump_file, "After Coalescing:\n");
|
fprintf (dump_file, "After Coalescing:\n");
|
dump_var_map (dump_file, map);
|
dump_var_map (dump_file, map);
|
}
|
}
|
|
|
if (perform_ter)
|
if (perform_ter)
|
{
|
{
|
values = find_replaceable_exprs (map);
|
values = find_replaceable_exprs (map);
|
if (values && dump_file && (dump_flags & TDF_DETAILS))
|
if (values && dump_file && (dump_flags & TDF_DETAILS))
|
dump_replaceable_exprs (dump_file, values);
|
dump_replaceable_exprs (dump_file, values);
|
}
|
}
|
|
|
rewrite_trees (map);
|
rewrite_trees (map);
|
|
|
sa->map = map;
|
sa->map = map;
|
sa->values = values;
|
sa->values = values;
|
sa->partition_has_default_def = BITMAP_ALLOC (NULL);
|
sa->partition_has_default_def = BITMAP_ALLOC (NULL);
|
for (i = 1; i < num_ssa_names; i++)
|
for (i = 1; i < num_ssa_names; i++)
|
{
|
{
|
tree t = ssa_name (i);
|
tree t = ssa_name (i);
|
if (t && SSA_NAME_IS_DEFAULT_DEF (t))
|
if (t && SSA_NAME_IS_DEFAULT_DEF (t))
|
{
|
{
|
int p = var_to_partition (map, t);
|
int p = var_to_partition (map, t);
|
if (p != NO_PARTITION)
|
if (p != NO_PARTITION)
|
bitmap_set_bit (sa->partition_has_default_def, p);
|
bitmap_set_bit (sa->partition_has_default_def, p);
|
}
|
}
|
}
|
}
|
}
|
}
|
|
|
|
|
/* If not already done so for basic block BB, assign increasing uids
|
/* If not already done so for basic block BB, assign increasing uids
|
to each of its instructions. */
|
to each of its instructions. */
|
|
|
static void
|
static void
|
maybe_renumber_stmts_bb (basic_block bb)
|
maybe_renumber_stmts_bb (basic_block bb)
|
{
|
{
|
unsigned i = 0;
|
unsigned i = 0;
|
gimple_stmt_iterator gsi;
|
gimple_stmt_iterator gsi;
|
|
|
if (!bb->aux)
|
if (!bb->aux)
|
return;
|
return;
|
bb->aux = NULL;
|
bb->aux = NULL;
|
for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
|
for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
|
{
|
{
|
gimple stmt = gsi_stmt (gsi);
|
gimple stmt = gsi_stmt (gsi);
|
gimple_set_uid (stmt, i);
|
gimple_set_uid (stmt, i);
|
i++;
|
i++;
|
}
|
}
|
}
|
}
|
|
|
|
|
/* Return true if we can determine that the SSA_NAMEs RESULT (a result
|
/* Return true if we can determine that the SSA_NAMEs RESULT (a result
|
of a PHI node) and ARG (one of its arguments) conflict. Return false
|
of a PHI node) and ARG (one of its arguments) conflict. Return false
|
otherwise, also when we simply aren't sure. */
|
otherwise, also when we simply aren't sure. */
|
|
|
static bool
|
static bool
|
trivially_conflicts_p (basic_block bb, tree result, tree arg)
|
trivially_conflicts_p (basic_block bb, tree result, tree arg)
|
{
|
{
|
use_operand_p use;
|
use_operand_p use;
|
imm_use_iterator imm_iter;
|
imm_use_iterator imm_iter;
|
gimple defa = SSA_NAME_DEF_STMT (arg);
|
gimple defa = SSA_NAME_DEF_STMT (arg);
|
|
|
/* If ARG isn't defined in the same block it's too complicated for
|
/* If ARG isn't defined in the same block it's too complicated for
|
our little mind. */
|
our little mind. */
|
if (gimple_bb (defa) != bb)
|
if (gimple_bb (defa) != bb)
|
return false;
|
return false;
|
|
|
FOR_EACH_IMM_USE_FAST (use, imm_iter, result)
|
FOR_EACH_IMM_USE_FAST (use, imm_iter, result)
|
{
|
{
|
gimple use_stmt = USE_STMT (use);
|
gimple use_stmt = USE_STMT (use);
|
if (is_gimple_debug (use_stmt))
|
if (is_gimple_debug (use_stmt))
|
continue;
|
continue;
|
/* Now, if there's a use of RESULT that lies outside this basic block,
|
/* Now, if there's a use of RESULT that lies outside this basic block,
|
then there surely is a conflict with ARG. */
|
then there surely is a conflict with ARG. */
|
if (gimple_bb (use_stmt) != bb)
|
if (gimple_bb (use_stmt) != bb)
|
return true;
|
return true;
|
if (gimple_code (use_stmt) == GIMPLE_PHI)
|
if (gimple_code (use_stmt) == GIMPLE_PHI)
|
continue;
|
continue;
|
/* The use now is in a real stmt of BB, so if ARG was defined
|
/* The use now is in a real stmt of BB, so if ARG was defined
|
in a PHI node (like RESULT) both conflict. */
|
in a PHI node (like RESULT) both conflict. */
|
if (gimple_code (defa) == GIMPLE_PHI)
|
if (gimple_code (defa) == GIMPLE_PHI)
|
return true;
|
return true;
|
maybe_renumber_stmts_bb (bb);
|
maybe_renumber_stmts_bb (bb);
|
/* If the use of RESULT occurs after the definition of ARG,
|
/* If the use of RESULT occurs after the definition of ARG,
|
the two conflict too. */
|
the two conflict too. */
|
if (gimple_uid (defa) < gimple_uid (use_stmt))
|
if (gimple_uid (defa) < gimple_uid (use_stmt))
|
return true;
|
return true;
|
}
|
}
|
|
|
return false;
|
return false;
|
}
|
}
|
|
|
|
|
/* Search every PHI node for arguments associated with backedges which
|
/* Search every PHI node for arguments associated with backedges which
|
we can trivially determine will need a copy (the argument is either
|
we can trivially determine will need a copy (the argument is either
|
not an SSA_NAME or the argument has a different underlying variable
|
not an SSA_NAME or the argument has a different underlying variable
|
than the PHI result).
|
than the PHI result).
|
|
|
Insert a copy from the PHI argument to a new destination at the
|
Insert a copy from the PHI argument to a new destination at the
|
end of the block with the backedge to the top of the loop. Update
|
end of the block with the backedge to the top of the loop. Update
|
the PHI argument to reference this new destination. */
|
the PHI argument to reference this new destination. */
|
|
|
static void
|
static void
|
insert_backedge_copies (void)
|
insert_backedge_copies (void)
|
{
|
{
|
basic_block bb;
|
basic_block bb;
|
gimple_stmt_iterator gsi;
|
gimple_stmt_iterator gsi;
|
|
|
FOR_EACH_BB (bb)
|
FOR_EACH_BB (bb)
|
{
|
{
|
/* Mark block as possibly needing calculation of UIDs. */
|
/* Mark block as possibly needing calculation of UIDs. */
|
bb->aux = &bb->aux;
|
bb->aux = &bb->aux;
|
|
|
for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
|
for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
|
{
|
{
|
gimple phi = gsi_stmt (gsi);
|
gimple phi = gsi_stmt (gsi);
|
tree result = gimple_phi_result (phi);
|
tree result = gimple_phi_result (phi);
|
tree result_var;
|
tree result_var;
|
size_t i;
|
size_t i;
|
|
|
if (!is_gimple_reg (result))
|
if (!is_gimple_reg (result))
|
continue;
|
continue;
|
|
|
result_var = SSA_NAME_VAR (result);
|
result_var = SSA_NAME_VAR (result);
|
for (i = 0; i < gimple_phi_num_args (phi); i++)
|
for (i = 0; i < gimple_phi_num_args (phi); i++)
|
{
|
{
|
tree arg = gimple_phi_arg_def (phi, i);
|
tree arg = gimple_phi_arg_def (phi, i);
|
edge e = gimple_phi_arg_edge (phi, i);
|
edge e = gimple_phi_arg_edge (phi, i);
|
|
|
/* If the argument is not an SSA_NAME, then we will need a
|
/* If the argument is not an SSA_NAME, then we will need a
|
constant initialization. If the argument is an SSA_NAME with
|
constant initialization. If the argument is an SSA_NAME with
|
a different underlying variable then a copy statement will be
|
a different underlying variable then a copy statement will be
|
needed. */
|
needed. */
|
if ((e->flags & EDGE_DFS_BACK)
|
if ((e->flags & EDGE_DFS_BACK)
|
&& (TREE_CODE (arg) != SSA_NAME
|
&& (TREE_CODE (arg) != SSA_NAME
|
|| SSA_NAME_VAR (arg) != result_var
|
|| SSA_NAME_VAR (arg) != result_var
|
|| trivially_conflicts_p (bb, result, arg)))
|
|| trivially_conflicts_p (bb, result, arg)))
|
{
|
{
|
tree name;
|
tree name;
|
gimple stmt, last = NULL;
|
gimple stmt, last = NULL;
|
gimple_stmt_iterator gsi2;
|
gimple_stmt_iterator gsi2;
|
|
|
gsi2 = gsi_last_bb (gimple_phi_arg_edge (phi, i)->src);
|
gsi2 = gsi_last_bb (gimple_phi_arg_edge (phi, i)->src);
|
if (!gsi_end_p (gsi2))
|
if (!gsi_end_p (gsi2))
|
last = gsi_stmt (gsi2);
|
last = gsi_stmt (gsi2);
|
|
|
/* In theory the only way we ought to get back to the
|
/* In theory the only way we ought to get back to the
|
start of a loop should be with a COND_EXPR or GOTO_EXPR.
|
start of a loop should be with a COND_EXPR or GOTO_EXPR.
|
However, better safe than sorry.
|
However, better safe than sorry.
|
If the block ends with a control statement or
|
If the block ends with a control statement or
|
something that might throw, then we have to
|
something that might throw, then we have to
|
insert this assignment before the last
|
insert this assignment before the last
|
statement. Else insert it after the last statement. */
|
statement. Else insert it after the last statement. */
|
if (last && stmt_ends_bb_p (last))
|
if (last && stmt_ends_bb_p (last))
|
{
|
{
|
/* If the last statement in the block is the definition
|
/* If the last statement in the block is the definition
|
site of the PHI argument, then we can't insert
|
site of the PHI argument, then we can't insert
|
anything after it. */
|
anything after it. */
|
if (TREE_CODE (arg) == SSA_NAME
|
if (TREE_CODE (arg) == SSA_NAME
|
&& SSA_NAME_DEF_STMT (arg) == last)
|
&& SSA_NAME_DEF_STMT (arg) == last)
|
continue;
|
continue;
|
}
|
}
|
|
|
/* Create a new instance of the underlying variable of the
|
/* Create a new instance of the underlying variable of the
|
PHI result. */
|
PHI result. */
|
stmt = gimple_build_assign (result_var,
|
stmt = gimple_build_assign (result_var,
|
gimple_phi_arg_def (phi, i));
|
gimple_phi_arg_def (phi, i));
|
name = make_ssa_name (result_var, stmt);
|
name = make_ssa_name (result_var, stmt);
|
gimple_assign_set_lhs (stmt, name);
|
gimple_assign_set_lhs (stmt, name);
|
|
|
/* copy location if present. */
|
/* copy location if present. */
|
if (gimple_phi_arg_has_location (phi, i))
|
if (gimple_phi_arg_has_location (phi, i))
|
gimple_set_location (stmt,
|
gimple_set_location (stmt,
|
gimple_phi_arg_location (phi, i));
|
gimple_phi_arg_location (phi, i));
|
|
|
/* Insert the new statement into the block and update
|
/* Insert the new statement into the block and update
|
the PHI node. */
|
the PHI node. */
|
if (last && stmt_ends_bb_p (last))
|
if (last && stmt_ends_bb_p (last))
|
gsi_insert_before (&gsi2, stmt, GSI_NEW_STMT);
|
gsi_insert_before (&gsi2, stmt, GSI_NEW_STMT);
|
else
|
else
|
gsi_insert_after (&gsi2, stmt, GSI_NEW_STMT);
|
gsi_insert_after (&gsi2, stmt, GSI_NEW_STMT);
|
SET_PHI_ARG_DEF (phi, i, name);
|
SET_PHI_ARG_DEF (phi, i, name);
|
}
|
}
|
}
|
}
|
}
|
}
|
|
|
/* Unmark this block again. */
|
/* Unmark this block again. */
|
bb->aux = NULL;
|
bb->aux = NULL;
|
}
|
}
|
}
|
}
|
|
|
/* Free all memory associated with going out of SSA form. SA is
|
/* Free all memory associated with going out of SSA form. SA is
|
the outof-SSA info object. */
|
the outof-SSA info object. */
|
|
|
void
|
void
|
finish_out_of_ssa (struct ssaexpand *sa)
|
finish_out_of_ssa (struct ssaexpand *sa)
|
{
|
{
|
free (sa->partition_to_pseudo);
|
free (sa->partition_to_pseudo);
|
if (sa->values)
|
if (sa->values)
|
BITMAP_FREE (sa->values);
|
BITMAP_FREE (sa->values);
|
delete_var_map (sa->map);
|
delete_var_map (sa->map);
|
BITMAP_FREE (sa->partition_has_default_def);
|
BITMAP_FREE (sa->partition_has_default_def);
|
memset (sa, 0, sizeof *sa);
|
memset (sa, 0, sizeof *sa);
|
}
|
}
|
|
|
/* Take the current function out of SSA form, translating PHIs as described in
|
/* Take the current function out of SSA form, translating PHIs as described in
|
R. Morgan, ``Building an Optimizing Compiler'',
|
R. Morgan, ``Building an Optimizing Compiler'',
|
Butterworth-Heinemann, Boston, MA, 1998. pp 176-186. */
|
Butterworth-Heinemann, Boston, MA, 1998. pp 176-186. */
|
|
|
unsigned int
|
unsigned int
|
rewrite_out_of_ssa (struct ssaexpand *sa)
|
rewrite_out_of_ssa (struct ssaexpand *sa)
|
{
|
{
|
/* If elimination of a PHI requires inserting a copy on a backedge,
|
/* If elimination of a PHI requires inserting a copy on a backedge,
|
then we will have to split the backedge which has numerous
|
then we will have to split the backedge which has numerous
|
undesirable performance effects.
|
undesirable performance effects.
|
|
|
A significant number of such cases can be handled here by inserting
|
A significant number of such cases can be handled here by inserting
|
copies into the loop itself. */
|
copies into the loop itself. */
|
insert_backedge_copies ();
|
insert_backedge_copies ();
|
|
|
|
|
/* Eliminate PHIs which are of no use, such as virtual or dead phis. */
|
/* Eliminate PHIs which are of no use, such as virtual or dead phis. */
|
eliminate_useless_phis ();
|
eliminate_useless_phis ();
|
|
|
if (dump_file && (dump_flags & TDF_DETAILS))
|
if (dump_file && (dump_flags & TDF_DETAILS))
|
gimple_dump_cfg (dump_file, dump_flags & ~TDF_DETAILS);
|
gimple_dump_cfg (dump_file, dump_flags & ~TDF_DETAILS);
|
|
|
remove_ssa_form (flag_tree_ter, sa);
|
remove_ssa_form (flag_tree_ter, sa);
|
|
|
if (dump_file && (dump_flags & TDF_DETAILS))
|
if (dump_file && (dump_flags & TDF_DETAILS))
|
gimple_dump_cfg (dump_file, dump_flags & ~TDF_DETAILS);
|
gimple_dump_cfg (dump_file, dump_flags & ~TDF_DETAILS);
|
|
|
return 0;
|
return 0;
|
}
|
}
|
|
|
