/* Backward propagation of indirect loads through PHIs.
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/* Backward propagation of indirect loads through PHIs.
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Copyright (C) 2007, 2008 Free Software Foundation, Inc.
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Copyright (C) 2007, 2008 Free Software Foundation, Inc.
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Contributed by Richard Guenther <rguenther@suse.de>
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Contributed by Richard Guenther <rguenther@suse.de>
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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 "ggc.h"
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#include "ggc.h"
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#include "tree.h"
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#include "tree.h"
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#include "rtl.h"
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#include "rtl.h"
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#include "tm_p.h"
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#include "tm_p.h"
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#include "basic-block.h"
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#include "basic-block.h"
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#include "timevar.h"
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#include "timevar.h"
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#include "diagnostic.h"
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#include "diagnostic.h"
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#include "tree-flow.h"
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#include "tree-flow.h"
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#include "tree-pass.h"
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#include "tree-pass.h"
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#include "tree-dump.h"
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#include "tree-dump.h"
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#include "langhooks.h"
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#include "langhooks.h"
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#include "flags.h"
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#include "flags.h"
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/* This pass propagates indirect loads through the PHI node for its
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/* This pass propagates indirect loads through the PHI node for its
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address to make the load source possibly non-addressable and to
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address to make the load source possibly non-addressable and to
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allow for PHI optimization to trigger.
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allow for PHI optimization to trigger.
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For example the pass changes
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For example the pass changes
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# addr_1 = PHI <&a, &b>
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# addr_1 = PHI <&a, &b>
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tmp_1 = *addr_1;
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tmp_1 = *addr_1;
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to
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to
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# tmp_1 = PHI <a, b>
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# tmp_1 = PHI <a, b>
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but also handles more complex scenarios like
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but also handles more complex scenarios like
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D.2077_2 = &this_1(D)->a1;
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D.2077_2 = &this_1(D)->a1;
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...
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...
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# b_12 = PHI <&c(2), D.2077_2(3)>
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# b_12 = PHI <&c(2), D.2077_2(3)>
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D.2114_13 = *b_12;
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D.2114_13 = *b_12;
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...
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...
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# b_15 = PHI <b_12(4), &b(5)>
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# b_15 = PHI <b_12(4), &b(5)>
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D.2080_5 = &this_1(D)->a0;
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D.2080_5 = &this_1(D)->a0;
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...
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...
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# b_18 = PHI <D.2080_5(6), &c(7)>
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# b_18 = PHI <D.2080_5(6), &c(7)>
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...
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...
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# b_21 = PHI <b_15(8), b_18(9)>
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# b_21 = PHI <b_15(8), b_18(9)>
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D.2076_8 = *b_21;
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D.2076_8 = *b_21;
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where the addresses loaded are defined by PHIs itself.
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where the addresses loaded are defined by PHIs itself.
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The above happens for
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The above happens for
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std::max(std::min(a0, c), std::min(std::max(a1, c), b))
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std::max(std::min(a0, c), std::min(std::max(a1, c), b))
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where this pass transforms it to a form later PHI optimization
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where this pass transforms it to a form later PHI optimization
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recognizes and transforms it to the simple
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recognizes and transforms it to the simple
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D.2109_10 = this_1(D)->a1;
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D.2109_10 = this_1(D)->a1;
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D.2110_11 = c;
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D.2110_11 = c;
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D.2114_31 = MAX_EXPR <D.2109_10, D.2110_11>;
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D.2114_31 = MAX_EXPR <D.2109_10, D.2110_11>;
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D.2115_14 = b;
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D.2115_14 = b;
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D.2125_17 = MIN_EXPR <D.2115_14, D.2114_31>;
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D.2125_17 = MIN_EXPR <D.2115_14, D.2114_31>;
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D.2119_16 = this_1(D)->a0;
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D.2119_16 = this_1(D)->a0;
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D.2124_32 = MIN_EXPR <D.2110_11, D.2119_16>;
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D.2124_32 = MIN_EXPR <D.2110_11, D.2119_16>;
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D.2076_33 = MAX_EXPR <D.2125_17, D.2124_32>;
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D.2076_33 = MAX_EXPR <D.2125_17, D.2124_32>;
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The pass does a dominator walk processing loads using a basic-block
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The pass does a dominator walk processing loads using a basic-block
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local analysis and stores the result for use by transformations on
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local analysis and stores the result for use by transformations on
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dominated basic-blocks. */
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dominated basic-blocks. */
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/* Structure to keep track of the value of a dereferenced PHI result
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/* Structure to keep track of the value of a dereferenced PHI result
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and the virtual operand used for that dereference. */
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and the virtual operand used for that dereference. */
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struct phiprop_d
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struct phiprop_d
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{
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{
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tree value;
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tree value;
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tree vuse;
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tree vuse;
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};
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};
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/* Verify if the value recorded for NAME in PHIVN is still valid at
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/* Verify if the value recorded for NAME in PHIVN is still valid at
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the start of basic block BB. */
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the start of basic block BB. */
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static bool
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static bool
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phivn_valid_p (struct phiprop_d *phivn, tree name, basic_block bb)
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phivn_valid_p (struct phiprop_d *phivn, tree name, basic_block bb)
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{
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{
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tree vuse = phivn[SSA_NAME_VERSION (name)].vuse;
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tree vuse = phivn[SSA_NAME_VERSION (name)].vuse;
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gimple use_stmt;
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gimple use_stmt;
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imm_use_iterator ui2;
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imm_use_iterator ui2;
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bool ok = true;
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bool ok = true;
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/* The def stmts of the virtual uses need to be dominated by bb. */
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/* The def stmts of the virtual uses need to be dominated by bb. */
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gcc_assert (vuse != NULL_TREE);
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gcc_assert (vuse != NULL_TREE);
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FOR_EACH_IMM_USE_STMT (use_stmt, ui2, vuse)
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FOR_EACH_IMM_USE_STMT (use_stmt, ui2, vuse)
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{
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{
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/* If BB does not dominate a VDEF, the value is invalid. */
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/* If BB does not dominate a VDEF, the value is invalid. */
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if ((gimple_vdef (use_stmt) != NULL_TREE
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if ((gimple_vdef (use_stmt) != NULL_TREE
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|| gimple_code (use_stmt) == GIMPLE_PHI)
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|| gimple_code (use_stmt) == GIMPLE_PHI)
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&& !dominated_by_p (CDI_DOMINATORS, gimple_bb (use_stmt), bb))
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&& !dominated_by_p (CDI_DOMINATORS, gimple_bb (use_stmt), bb))
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{
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{
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ok = false;
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ok = false;
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BREAK_FROM_IMM_USE_STMT (ui2);
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BREAK_FROM_IMM_USE_STMT (ui2);
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}
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}
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}
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}
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return ok;
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return ok;
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}
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}
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/* Insert a new phi node for the dereference of PHI at basic_block
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/* Insert a new phi node for the dereference of PHI at basic_block
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BB with the virtual operands from USE_STMT. */
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BB with the virtual operands from USE_STMT. */
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static tree
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static tree
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phiprop_insert_phi (basic_block bb, gimple phi, gimple use_stmt,
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phiprop_insert_phi (basic_block bb, gimple phi, gimple use_stmt,
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struct phiprop_d *phivn, size_t n)
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struct phiprop_d *phivn, size_t n)
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{
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{
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tree res;
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tree res;
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gimple new_phi;
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gimple new_phi;
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edge_iterator ei;
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edge_iterator ei;
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edge e;
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edge e;
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gcc_assert (is_gimple_assign (use_stmt)
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gcc_assert (is_gimple_assign (use_stmt)
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&& gimple_assign_rhs_code (use_stmt) == INDIRECT_REF);
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&& gimple_assign_rhs_code (use_stmt) == INDIRECT_REF);
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/* Build a new PHI node to replace the definition of
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/* Build a new PHI node to replace the definition of
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the indirect reference lhs. */
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the indirect reference lhs. */
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res = gimple_assign_lhs (use_stmt);
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res = gimple_assign_lhs (use_stmt);
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SSA_NAME_DEF_STMT (res) = new_phi = create_phi_node (res, bb);
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SSA_NAME_DEF_STMT (res) = new_phi = create_phi_node (res, bb);
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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, "Inserting PHI for result of load ");
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fprintf (dump_file, "Inserting PHI for result of load ");
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print_gimple_stmt (dump_file, use_stmt, 0, 0);
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print_gimple_stmt (dump_file, use_stmt, 0, 0);
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}
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}
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/* Add PHI arguments for each edge inserting loads of the
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/* Add PHI arguments for each edge inserting loads of the
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addressable operands. */
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addressable operands. */
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FOR_EACH_EDGE (e, ei, bb->preds)
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FOR_EACH_EDGE (e, ei, bb->preds)
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{
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{
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tree old_arg, new_var;
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tree old_arg, new_var;
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gimple tmp;
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gimple tmp;
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source_location locus;
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source_location locus;
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old_arg = PHI_ARG_DEF_FROM_EDGE (phi, e);
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old_arg = PHI_ARG_DEF_FROM_EDGE (phi, e);
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locus = gimple_phi_arg_location_from_edge (phi, e);
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locus = gimple_phi_arg_location_from_edge (phi, e);
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while (TREE_CODE (old_arg) == SSA_NAME
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while (TREE_CODE (old_arg) == SSA_NAME
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&& (SSA_NAME_VERSION (old_arg) >= n
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&& (SSA_NAME_VERSION (old_arg) >= n
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|| phivn[SSA_NAME_VERSION (old_arg)].value == NULL_TREE))
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|| phivn[SSA_NAME_VERSION (old_arg)].value == NULL_TREE))
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{
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{
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gimple def_stmt = SSA_NAME_DEF_STMT (old_arg);
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gimple def_stmt = SSA_NAME_DEF_STMT (old_arg);
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old_arg = gimple_assign_rhs1 (def_stmt);
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old_arg = gimple_assign_rhs1 (def_stmt);
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locus = gimple_location (def_stmt);
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locus = gimple_location (def_stmt);
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}
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}
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if (TREE_CODE (old_arg) == SSA_NAME)
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if (TREE_CODE (old_arg) == SSA_NAME)
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{
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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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{
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fprintf (dump_file, " for edge defining ");
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fprintf (dump_file, " for edge defining ");
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print_generic_expr (dump_file, PHI_ARG_DEF_FROM_EDGE (phi, e), 0);
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print_generic_expr (dump_file, PHI_ARG_DEF_FROM_EDGE (phi, e), 0);
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fprintf (dump_file, " reusing PHI result ");
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fprintf (dump_file, " reusing PHI result ");
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print_generic_expr (dump_file,
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print_generic_expr (dump_file,
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phivn[SSA_NAME_VERSION (old_arg)].value, 0);
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phivn[SSA_NAME_VERSION (old_arg)].value, 0);
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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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/* Reuse a formerly created dereference. */
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/* Reuse a formerly created dereference. */
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new_var = phivn[SSA_NAME_VERSION (old_arg)].value;
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new_var = phivn[SSA_NAME_VERSION (old_arg)].value;
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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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gcc_assert (TREE_CODE (old_arg) == ADDR_EXPR);
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gcc_assert (TREE_CODE (old_arg) == ADDR_EXPR);
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old_arg = TREE_OPERAND (old_arg, 0);
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old_arg = TREE_OPERAND (old_arg, 0);
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new_var = create_tmp_var (TREE_TYPE (old_arg), NULL);
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new_var = create_tmp_var (TREE_TYPE (old_arg), NULL);
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tmp = gimple_build_assign (new_var, unshare_expr (old_arg));
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tmp = gimple_build_assign (new_var, unshare_expr (old_arg));
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if (TREE_CODE (TREE_TYPE (old_arg)) == COMPLEX_TYPE
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if (TREE_CODE (TREE_TYPE (old_arg)) == COMPLEX_TYPE
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|| TREE_CODE (TREE_TYPE (old_arg)) == VECTOR_TYPE)
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|| TREE_CODE (TREE_TYPE (old_arg)) == VECTOR_TYPE)
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DECL_GIMPLE_REG_P (new_var) = 1;
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DECL_GIMPLE_REG_P (new_var) = 1;
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gcc_assert (is_gimple_reg (new_var));
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gcc_assert (is_gimple_reg (new_var));
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add_referenced_var (new_var);
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add_referenced_var (new_var);
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new_var = make_ssa_name (new_var, tmp);
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new_var = make_ssa_name (new_var, tmp);
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gimple_assign_set_lhs (tmp, new_var);
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gimple_assign_set_lhs (tmp, new_var);
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gimple_set_location (tmp, locus);
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gimple_set_location (tmp, locus);
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gsi_insert_on_edge (e, tmp);
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gsi_insert_on_edge (e, tmp);
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update_stmt (tmp);
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update_stmt (tmp);
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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, " for edge defining ");
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fprintf (dump_file, " for edge defining ");
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print_generic_expr (dump_file, PHI_ARG_DEF_FROM_EDGE (phi, e), 0);
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print_generic_expr (dump_file, PHI_ARG_DEF_FROM_EDGE (phi, e), 0);
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fprintf (dump_file, " inserting load ");
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fprintf (dump_file, " inserting load ");
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print_gimple_stmt (dump_file, tmp, 0, 0);
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print_gimple_stmt (dump_file, tmp, 0, 0);
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}
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}
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}
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}
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add_phi_arg (new_phi, new_var, e, locus);
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add_phi_arg (new_phi, new_var, e, locus);
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}
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}
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update_stmt (new_phi);
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update_stmt (new_phi);
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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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print_gimple_stmt (dump_file, new_phi, 0, 0);
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print_gimple_stmt (dump_file, new_phi, 0, 0);
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return res;
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return res;
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}
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}
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/* Propagate between the phi node arguments of PHI in BB and phi result
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/* Propagate between the phi node arguments of PHI in BB and phi result
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users. For now this matches
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users. For now this matches
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# p_2 = PHI <&x, &y>
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# p_2 = PHI <&x, &y>
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<Lx>:;
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<Lx>:;
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p_3 = p_2;
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p_3 = p_2;
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z_2 = *p_3;
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z_2 = *p_3;
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and converts it to
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and converts it to
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# z_2 = PHI <x, y>
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# z_2 = PHI <x, y>
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<Lx>:;
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<Lx>:;
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Returns true if a transformation was done and edge insertions
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Returns true if a transformation was done and edge insertions
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need to be committed. Global data PHIVN and N is used to track
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need to be committed. Global data PHIVN and N is used to track
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past transformation results. We need to be especially careful here
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past transformation results. We need to be especially careful here
|
with aliasing issues as we are moving memory reads. */
|
with aliasing issues as we are moving memory reads. */
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|
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static bool
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static bool
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propagate_with_phi (basic_block bb, gimple phi, struct phiprop_d *phivn,
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propagate_with_phi (basic_block bb, gimple phi, struct phiprop_d *phivn,
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size_t n)
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size_t n)
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{
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{
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tree ptr = PHI_RESULT (phi);
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tree ptr = PHI_RESULT (phi);
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gimple use_stmt;
|
gimple use_stmt;
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tree res = NULL_TREE;
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tree res = NULL_TREE;
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gimple_stmt_iterator gsi;
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gimple_stmt_iterator gsi;
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imm_use_iterator ui;
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imm_use_iterator ui;
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use_operand_p arg_p, use;
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use_operand_p arg_p, use;
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ssa_op_iter i;
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ssa_op_iter i;
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bool phi_inserted;
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bool phi_inserted;
|
|
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if (!POINTER_TYPE_P (TREE_TYPE (ptr))
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if (!POINTER_TYPE_P (TREE_TYPE (ptr))
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|| !is_gimple_reg_type (TREE_TYPE (TREE_TYPE (ptr))))
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|| !is_gimple_reg_type (TREE_TYPE (TREE_TYPE (ptr))))
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return false;
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return false;
|
|
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/* Check if we can "cheaply" dereference all phi arguments. */
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/* Check if we can "cheaply" dereference all phi arguments. */
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FOR_EACH_PHI_ARG (arg_p, phi, i, SSA_OP_USE)
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FOR_EACH_PHI_ARG (arg_p, phi, i, SSA_OP_USE)
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{
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{
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tree arg = USE_FROM_PTR (arg_p);
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tree arg = USE_FROM_PTR (arg_p);
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/* Walk the ssa chain until we reach a ssa name we already
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/* Walk the ssa chain until we reach a ssa name we already
|
created a value for or we reach a definition of the form
|
created a value for or we reach a definition of the form
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ssa_name_n = &var; */
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ssa_name_n = &var; */
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while (TREE_CODE (arg) == SSA_NAME
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while (TREE_CODE (arg) == SSA_NAME
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&& !SSA_NAME_IS_DEFAULT_DEF (arg)
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&& !SSA_NAME_IS_DEFAULT_DEF (arg)
|
&& (SSA_NAME_VERSION (arg) >= n
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&& (SSA_NAME_VERSION (arg) >= n
|
|| phivn[SSA_NAME_VERSION (arg)].value == NULL_TREE))
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|| phivn[SSA_NAME_VERSION (arg)].value == NULL_TREE))
|
{
|
{
|
gimple def_stmt = SSA_NAME_DEF_STMT (arg);
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gimple def_stmt = SSA_NAME_DEF_STMT (arg);
|
if (!gimple_assign_single_p (def_stmt))
|
if (!gimple_assign_single_p (def_stmt))
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return false;
|
return false;
|
arg = gimple_assign_rhs1 (def_stmt);
|
arg = gimple_assign_rhs1 (def_stmt);
|
}
|
}
|
if ((TREE_CODE (arg) != ADDR_EXPR
|
if ((TREE_CODE (arg) != ADDR_EXPR
|
/* Avoid to have to decay *&a to a[0] later. */
|
/* Avoid to have to decay *&a to a[0] later. */
|
|| !is_gimple_reg_type (TREE_TYPE (TREE_OPERAND (arg, 0))))
|
|| !is_gimple_reg_type (TREE_TYPE (TREE_OPERAND (arg, 0))))
|
&& !(TREE_CODE (arg) == SSA_NAME
|
&& !(TREE_CODE (arg) == SSA_NAME
|
&& SSA_NAME_VERSION (arg) < n
|
&& SSA_NAME_VERSION (arg) < n
|
&& phivn[SSA_NAME_VERSION (arg)].value != NULL_TREE
|
&& phivn[SSA_NAME_VERSION (arg)].value != NULL_TREE
|
&& phivn_valid_p (phivn, arg, bb)))
|
&& phivn_valid_p (phivn, arg, bb)))
|
return false;
|
return false;
|
}
|
}
|
|
|
/* Find a dereferencing use. First follow (single use) ssa
|
/* Find a dereferencing use. First follow (single use) ssa
|
copy chains for ptr. */
|
copy chains for ptr. */
|
while (single_imm_use (ptr, &use, &use_stmt)
|
while (single_imm_use (ptr, &use, &use_stmt)
|
&& gimple_assign_ssa_name_copy_p (use_stmt))
|
&& gimple_assign_ssa_name_copy_p (use_stmt))
|
ptr = gimple_assign_lhs (use_stmt);
|
ptr = gimple_assign_lhs (use_stmt);
|
|
|
/* Replace the first dereference of *ptr if there is one and if we
|
/* Replace the first dereference of *ptr if there is one and if we
|
can move the loads to the place of the ptr phi node. */
|
can move the loads to the place of the ptr phi node. */
|
phi_inserted = false;
|
phi_inserted = false;
|
FOR_EACH_IMM_USE_STMT (use_stmt, ui, ptr)
|
FOR_EACH_IMM_USE_STMT (use_stmt, ui, ptr)
|
{
|
{
|
gimple def_stmt;
|
gimple def_stmt;
|
tree vuse;
|
tree vuse;
|
|
|
/* Check whether this is a load of *ptr. */
|
/* Check whether this is a load of *ptr. */
|
if (!(is_gimple_assign (use_stmt)
|
if (!(is_gimple_assign (use_stmt)
|
&& TREE_CODE (gimple_assign_lhs (use_stmt)) == SSA_NAME
|
&& TREE_CODE (gimple_assign_lhs (use_stmt)) == SSA_NAME
|
&& gimple_assign_rhs_code (use_stmt) == INDIRECT_REF
|
&& gimple_assign_rhs_code (use_stmt) == INDIRECT_REF
|
&& TREE_OPERAND (gimple_assign_rhs1 (use_stmt), 0) == ptr
|
&& TREE_OPERAND (gimple_assign_rhs1 (use_stmt), 0) == ptr
|
/* We cannot replace a load that may throw or is volatile. */
|
/* We cannot replace a load that may throw or is volatile. */
|
&& !stmt_can_throw_internal (use_stmt)))
|
&& !stmt_can_throw_internal (use_stmt)))
|
continue;
|
continue;
|
|
|
/* Check if we can move the loads. The def stmt of the virtual use
|
/* Check if we can move the loads. The def stmt of the virtual use
|
needs to be in a different basic block dominating bb. */
|
needs to be in a different basic block dominating bb. */
|
vuse = gimple_vuse (use_stmt);
|
vuse = gimple_vuse (use_stmt);
|
def_stmt = SSA_NAME_DEF_STMT (vuse);
|
def_stmt = SSA_NAME_DEF_STMT (vuse);
|
if (!SSA_NAME_IS_DEFAULT_DEF (vuse)
|
if (!SSA_NAME_IS_DEFAULT_DEF (vuse)
|
&& (gimple_bb (def_stmt) == bb
|
&& (gimple_bb (def_stmt) == bb
|
|| !dominated_by_p (CDI_DOMINATORS,
|
|| !dominated_by_p (CDI_DOMINATORS,
|
bb, gimple_bb (def_stmt))))
|
bb, gimple_bb (def_stmt))))
|
goto next;
|
goto next;
|
|
|
/* Found a proper dereference. Insert a phi node if this
|
/* Found a proper dereference. Insert a phi node if this
|
is the first load transformation. */
|
is the first load transformation. */
|
if (!phi_inserted)
|
if (!phi_inserted)
|
{
|
{
|
res = phiprop_insert_phi (bb, phi, use_stmt, phivn, n);
|
res = phiprop_insert_phi (bb, phi, use_stmt, phivn, n);
|
|
|
/* Remember the value we created for *ptr. */
|
/* Remember the value we created for *ptr. */
|
phivn[SSA_NAME_VERSION (ptr)].value = res;
|
phivn[SSA_NAME_VERSION (ptr)].value = res;
|
phivn[SSA_NAME_VERSION (ptr)].vuse = vuse;
|
phivn[SSA_NAME_VERSION (ptr)].vuse = vuse;
|
|
|
/* Remove old stmt. The phi is taken care of by DCE, if we
|
/* Remove old stmt. The phi is taken care of by DCE, if we
|
want to delete it here we also have to delete all intermediate
|
want to delete it here we also have to delete all intermediate
|
copies. */
|
copies. */
|
gsi = gsi_for_stmt (use_stmt);
|
gsi = gsi_for_stmt (use_stmt);
|
gsi_remove (&gsi, false);
|
gsi_remove (&gsi, false);
|
|
|
phi_inserted = true;
|
phi_inserted = true;
|
}
|
}
|
else
|
else
|
{
|
{
|
/* Further replacements are easy, just make a copy out of the
|
/* Further replacements are easy, just make a copy out of the
|
load. */
|
load. */
|
gimple_assign_set_rhs1 (use_stmt, res);
|
gimple_assign_set_rhs1 (use_stmt, res);
|
update_stmt (use_stmt);
|
update_stmt (use_stmt);
|
}
|
}
|
|
|
next:;
|
next:;
|
/* Continue searching for a proper dereference. */
|
/* Continue searching for a proper dereference. */
|
}
|
}
|
|
|
return phi_inserted;
|
return phi_inserted;
|
}
|
}
|
|
|
/* Main entry for phiprop pass. */
|
/* Main entry for phiprop pass. */
|
|
|
static unsigned int
|
static unsigned int
|
tree_ssa_phiprop (void)
|
tree_ssa_phiprop (void)
|
{
|
{
|
VEC(basic_block, heap) *bbs;
|
VEC(basic_block, heap) *bbs;
|
struct phiprop_d *phivn;
|
struct phiprop_d *phivn;
|
bool did_something = false;
|
bool did_something = false;
|
basic_block bb;
|
basic_block bb;
|
gimple_stmt_iterator gsi;
|
gimple_stmt_iterator gsi;
|
unsigned i;
|
unsigned i;
|
size_t n;
|
size_t n;
|
|
|
calculate_dominance_info (CDI_DOMINATORS);
|
calculate_dominance_info (CDI_DOMINATORS);
|
|
|
n = num_ssa_names;
|
n = num_ssa_names;
|
phivn = XCNEWVEC (struct phiprop_d, n);
|
phivn = XCNEWVEC (struct phiprop_d, n);
|
|
|
/* Walk the dominator tree in preorder. */
|
/* Walk the dominator tree in preorder. */
|
bbs = get_all_dominated_blocks (CDI_DOMINATORS,
|
bbs = get_all_dominated_blocks (CDI_DOMINATORS,
|
single_succ (ENTRY_BLOCK_PTR));
|
single_succ (ENTRY_BLOCK_PTR));
|
for (i = 0; VEC_iterate (basic_block, bbs, i, bb); ++i)
|
for (i = 0; VEC_iterate (basic_block, bbs, i, bb); ++i)
|
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))
|
did_something |= propagate_with_phi (bb, gsi_stmt (gsi), phivn, n);
|
did_something |= propagate_with_phi (bb, gsi_stmt (gsi), phivn, n);
|
|
|
if (did_something)
|
if (did_something)
|
gsi_commit_edge_inserts ();
|
gsi_commit_edge_inserts ();
|
|
|
VEC_free (basic_block, heap, bbs);
|
VEC_free (basic_block, heap, bbs);
|
free (phivn);
|
free (phivn);
|
|
|
return 0;
|
return 0;
|
}
|
}
|
|
|
static bool
|
static bool
|
gate_phiprop (void)
|
gate_phiprop (void)
|
{
|
{
|
return flag_tree_phiprop;
|
return flag_tree_phiprop;
|
}
|
}
|
|
|
struct gimple_opt_pass pass_phiprop =
|
struct gimple_opt_pass pass_phiprop =
|
{
|
{
|
{
|
{
|
GIMPLE_PASS,
|
GIMPLE_PASS,
|
"phiprop", /* name */
|
"phiprop", /* name */
|
gate_phiprop, /* gate */
|
gate_phiprop, /* gate */
|
tree_ssa_phiprop, /* execute */
|
tree_ssa_phiprop, /* execute */
|
NULL, /* sub */
|
NULL, /* sub */
|
NULL, /* next */
|
NULL, /* next */
|
0, /* static_pass_number */
|
0, /* static_pass_number */
|
TV_TREE_PHIPROP, /* tv_id */
|
TV_TREE_PHIPROP, /* tv_id */
|
PROP_cfg | PROP_ssa, /* properties_required */
|
PROP_cfg | PROP_ssa, /* properties_required */
|
0, /* properties_provided */
|
0, /* properties_provided */
|
0, /* properties_destroyed */
|
0, /* properties_destroyed */
|
0, /* todo_flags_start */
|
0, /* todo_flags_start */
|
TODO_dump_func
|
TODO_dump_func
|
| TODO_ggc_collect
|
| TODO_ggc_collect
|
| TODO_update_ssa
|
| TODO_update_ssa
|
| TODO_verify_ssa /* todo_flags_finish */
|
| TODO_verify_ssa /* todo_flags_finish */
|
}
|
}
|
};
|
};
|
|
|
