From 554fd8c5195424bdbcabf5de30fdc183aba391bd Mon Sep 17 00:00:00 2001 From: upstream source tree Date: Sun, 15 Mar 2015 20:14:05 -0400 Subject: obtained gcc-4.6.4.tar.bz2 from upstream website; verified gcc-4.6.4.tar.bz2.sig; imported gcc-4.6.4 source tree from verified upstream tarball. downloading a git-generated archive based on the 'upstream' tag should provide you with a source tree that is binary identical to the one extracted from the above tarball. if you have obtained the source via the command 'git clone', however, do note that line-endings of files in your working directory might differ from line-endings of the respective files in the upstream repository. --- gcc/tree-ssa-reassoc.c | 2306 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 2306 insertions(+) create mode 100644 gcc/tree-ssa-reassoc.c (limited to 'gcc/tree-ssa-reassoc.c') diff --git a/gcc/tree-ssa-reassoc.c b/gcc/tree-ssa-reassoc.c new file mode 100644 index 000000000..987ec6507 --- /dev/null +++ b/gcc/tree-ssa-reassoc.c @@ -0,0 +1,2306 @@ +/* Reassociation for trees. + Copyright (C) 2005, 2007, 2008, 2009, 2010, 2011 + Free Software Foundation, Inc. + Contributed by Daniel Berlin + +This file is part of GCC. + +GCC is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 3, or (at your option) +any later version. + +GCC is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +GNU General Public License for more details. + +You should have received a copy of the GNU General Public License +along with GCC; see the file COPYING3. If not see +. */ + +#include "config.h" +#include "system.h" +#include "coretypes.h" +#include "tm.h" +#include "tree.h" +#include "basic-block.h" +#include "tree-pretty-print.h" +#include "gimple-pretty-print.h" +#include "tree-inline.h" +#include "tree-flow.h" +#include "gimple.h" +#include "tree-dump.h" +#include "timevar.h" +#include "tree-iterator.h" +#include "tree-pass.h" +#include "alloc-pool.h" +#include "vec.h" +#include "langhooks.h" +#include "pointer-set.h" +#include "cfgloop.h" +#include "flags.h" + +/* This is a simple global reassociation pass. It is, in part, based + on the LLVM pass of the same name (They do some things more/less + than we do, in different orders, etc). + + It consists of five steps: + + 1. Breaking up subtract operations into addition + negate, where + it would promote the reassociation of adds. + + 2. Left linearization of the expression trees, so that (A+B)+(C+D) + becomes (((A+B)+C)+D), which is easier for us to rewrite later. + During linearization, we place the operands of the binary + expressions into a vector of operand_entry_t + + 3. Optimization of the operand lists, eliminating things like a + + -a, a & a, etc. + + 4. Rewrite the expression trees we linearized and optimized so + they are in proper rank order. + + 5. Repropagate negates, as nothing else will clean it up ATM. + + A bit of theory on #4, since nobody seems to write anything down + about why it makes sense to do it the way they do it: + + We could do this much nicer theoretically, but don't (for reasons + explained after how to do it theoretically nice :P). + + In order to promote the most redundancy elimination, you want + binary expressions whose operands are the same rank (or + preferably, the same value) exposed to the redundancy eliminator, + for possible elimination. + + So the way to do this if we really cared, is to build the new op + tree from the leaves to the roots, merging as you go, and putting the + new op on the end of the worklist, until you are left with one + thing on the worklist. + + IE if you have to rewrite the following set of operands (listed with + rank in parentheses), with opcode PLUS_EXPR: + + a (1), b (1), c (1), d (2), e (2) + + + We start with our merge worklist empty, and the ops list with all of + those on it. + + You want to first merge all leaves of the same rank, as much as + possible. + + So first build a binary op of + + mergetmp = a + b, and put "mergetmp" on the merge worklist. + + Because there is no three operand form of PLUS_EXPR, c is not going to + be exposed to redundancy elimination as a rank 1 operand. + + So you might as well throw it on the merge worklist (you could also + consider it to now be a rank two operand, and merge it with d and e, + but in this case, you then have evicted e from a binary op. So at + least in this situation, you can't win.) + + Then build a binary op of d + e + mergetmp2 = d + e + + and put mergetmp2 on the merge worklist. + + so merge worklist = {mergetmp, c, mergetmp2} + + Continue building binary ops of these operations until you have only + one operation left on the worklist. + + So we have + + build binary op + mergetmp3 = mergetmp + c + + worklist = {mergetmp2, mergetmp3} + + mergetmp4 = mergetmp2 + mergetmp3 + + worklist = {mergetmp4} + + because we have one operation left, we can now just set the original + statement equal to the result of that operation. + + This will at least expose a + b and d + e to redundancy elimination + as binary operations. + + For extra points, you can reuse the old statements to build the + mergetmps, since you shouldn't run out. + + So why don't we do this? + + Because it's expensive, and rarely will help. Most trees we are + reassociating have 3 or less ops. If they have 2 ops, they already + will be written into a nice single binary op. If you have 3 ops, a + single simple check suffices to tell you whether the first two are of the + same rank. If so, you know to order it + + mergetmp = op1 + op2 + newstmt = mergetmp + op3 + + instead of + mergetmp = op2 + op3 + newstmt = mergetmp + op1 + + If all three are of the same rank, you can't expose them all in a + single binary operator anyway, so the above is *still* the best you + can do. + + Thus, this is what we do. When we have three ops left, we check to see + what order to put them in, and call it a day. As a nod to vector sum + reduction, we check if any of the ops are really a phi node that is a + destructive update for the associating op, and keep the destructive + update together for vector sum reduction recognition. */ + + +/* Statistics */ +static struct +{ + int linearized; + int constants_eliminated; + int ops_eliminated; + int rewritten; +} reassociate_stats; + +/* Operator, rank pair. */ +typedef struct operand_entry +{ + unsigned int rank; + int id; + tree op; +} *operand_entry_t; + +static alloc_pool operand_entry_pool; + +/* This is used to assign a unique ID to each struct operand_entry + so that qsort results are identical on different hosts. */ +static int next_operand_entry_id; + +/* Starting rank number for a given basic block, so that we can rank + operations using unmovable instructions in that BB based on the bb + depth. */ +static long *bb_rank; + +/* Operand->rank hashtable. */ +static struct pointer_map_t *operand_rank; + + +/* Look up the operand rank structure for expression E. */ + +static inline long +find_operand_rank (tree e) +{ + void **slot = pointer_map_contains (operand_rank, e); + return slot ? (long) (intptr_t) *slot : -1; +} + +/* Insert {E,RANK} into the operand rank hashtable. */ + +static inline void +insert_operand_rank (tree e, long rank) +{ + void **slot; + gcc_assert (rank > 0); + slot = pointer_map_insert (operand_rank, e); + gcc_assert (!*slot); + *slot = (void *) (intptr_t) rank; +} + +/* Given an expression E, return the rank of the expression. */ + +static long +get_rank (tree e) +{ + /* Constants have rank 0. */ + if (is_gimple_min_invariant (e)) + return 0; + + /* SSA_NAME's have the rank of the expression they are the result + of. + For globals and uninitialized values, the rank is 0. + For function arguments, use the pre-setup rank. + For PHI nodes, stores, asm statements, etc, we use the rank of + the BB. + For simple operations, the rank is the maximum rank of any of + its operands, or the bb_rank, whichever is less. + I make no claims that this is optimal, however, it gives good + results. */ + + if (TREE_CODE (e) == SSA_NAME) + { + gimple stmt; + long rank, maxrank; + int i, n; + + if (TREE_CODE (SSA_NAME_VAR (e)) == PARM_DECL + && SSA_NAME_IS_DEFAULT_DEF (e)) + return find_operand_rank (e); + + stmt = SSA_NAME_DEF_STMT (e); + if (gimple_bb (stmt) == NULL) + return 0; + + if (!is_gimple_assign (stmt) + || gimple_vdef (stmt)) + return bb_rank[gimple_bb (stmt)->index]; + + /* If we already have a rank for this expression, use that. */ + rank = find_operand_rank (e); + if (rank != -1) + return rank; + + /* Otherwise, find the maximum rank for the operands, or the bb + rank, whichever is less. */ + rank = 0; + maxrank = bb_rank[gimple_bb(stmt)->index]; + if (gimple_assign_single_p (stmt)) + { + tree rhs = gimple_assign_rhs1 (stmt); + n = TREE_OPERAND_LENGTH (rhs); + if (n == 0) + rank = MAX (rank, get_rank (rhs)); + else + { + for (i = 0; + i < n && TREE_OPERAND (rhs, i) && rank != maxrank; i++) + rank = MAX(rank, get_rank (TREE_OPERAND (rhs, i))); + } + } + else + { + n = gimple_num_ops (stmt); + for (i = 1; i < n && rank != maxrank; i++) + { + gcc_assert (gimple_op (stmt, i)); + rank = MAX(rank, get_rank (gimple_op (stmt, i))); + } + } + + if (dump_file && (dump_flags & TDF_DETAILS)) + { + fprintf (dump_file, "Rank for "); + print_generic_expr (dump_file, e, 0); + fprintf (dump_file, " is %ld\n", (rank + 1)); + } + + /* Note the rank in the hashtable so we don't recompute it. */ + insert_operand_rank (e, (rank + 1)); + return (rank + 1); + } + + /* Globals, etc, are rank 0 */ + return 0; +} + +DEF_VEC_P(operand_entry_t); +DEF_VEC_ALLOC_P(operand_entry_t, heap); + +/* We want integer ones to end up last no matter what, since they are + the ones we can do the most with. */ +#define INTEGER_CONST_TYPE 1 << 3 +#define FLOAT_CONST_TYPE 1 << 2 +#define OTHER_CONST_TYPE 1 << 1 + +/* Classify an invariant tree into integer, float, or other, so that + we can sort them to be near other constants of the same type. */ +static inline int +constant_type (tree t) +{ + if (INTEGRAL_TYPE_P (TREE_TYPE (t))) + return INTEGER_CONST_TYPE; + else if (SCALAR_FLOAT_TYPE_P (TREE_TYPE (t))) + return FLOAT_CONST_TYPE; + else + return OTHER_CONST_TYPE; +} + +/* qsort comparison function to sort operand entries PA and PB by rank + so that the sorted array is ordered by rank in decreasing order. */ +static int +sort_by_operand_rank (const void *pa, const void *pb) +{ + const operand_entry_t oea = *(const operand_entry_t *)pa; + const operand_entry_t oeb = *(const operand_entry_t *)pb; + + /* It's nicer for optimize_expression if constants that are likely + to fold when added/multiplied//whatever are put next to each + other. Since all constants have rank 0, order them by type. */ + if (oeb->rank == 0 && oea->rank == 0) + { + if (constant_type (oeb->op) != constant_type (oea->op)) + return constant_type (oeb->op) - constant_type (oea->op); + else + /* To make sorting result stable, we use unique IDs to determine + order. */ + return oeb->id - oea->id; + } + + /* Lastly, make sure the versions that are the same go next to each + other. We use SSA_NAME_VERSION because it's stable. */ + if ((oeb->rank - oea->rank == 0) + && TREE_CODE (oea->op) == SSA_NAME + && TREE_CODE (oeb->op) == SSA_NAME) + { + if (SSA_NAME_VERSION (oeb->op) != SSA_NAME_VERSION (oea->op)) + return SSA_NAME_VERSION (oeb->op) - SSA_NAME_VERSION (oea->op); + else + return oeb->id - oea->id; + } + + if (oeb->rank != oea->rank) + return oeb->rank - oea->rank; + else + return oeb->id - oea->id; +} + +/* Add an operand entry to *OPS for the tree operand OP. */ + +static void +add_to_ops_vec (VEC(operand_entry_t, heap) **ops, tree op) +{ + operand_entry_t oe = (operand_entry_t) pool_alloc (operand_entry_pool); + + oe->op = op; + oe->rank = get_rank (op); + oe->id = next_operand_entry_id++; + VEC_safe_push (operand_entry_t, heap, *ops, oe); +} + +/* Return true if STMT is reassociable operation containing a binary + operation with tree code CODE, and is inside LOOP. */ + +static bool +is_reassociable_op (gimple stmt, enum tree_code code, struct loop *loop) +{ + basic_block bb = gimple_bb (stmt); + + if (gimple_bb (stmt) == NULL) + return false; + + if (!flow_bb_inside_loop_p (loop, bb)) + return false; + + if (is_gimple_assign (stmt) + && gimple_assign_rhs_code (stmt) == code + && has_single_use (gimple_assign_lhs (stmt))) + return true; + + return false; +} + + +/* Given NAME, if NAME is defined by a unary operation OPCODE, return the + operand of the negate operation. Otherwise, return NULL. */ + +static tree +get_unary_op (tree name, enum tree_code opcode) +{ + gimple stmt = SSA_NAME_DEF_STMT (name); + + if (!is_gimple_assign (stmt)) + return NULL_TREE; + + if (gimple_assign_rhs_code (stmt) == opcode) + return gimple_assign_rhs1 (stmt); + return NULL_TREE; +} + +/* If CURR and LAST are a pair of ops that OPCODE allows us to + eliminate through equivalences, do so, remove them from OPS, and + return true. Otherwise, return false. */ + +static bool +eliminate_duplicate_pair (enum tree_code opcode, + VEC (operand_entry_t, heap) **ops, + bool *all_done, + unsigned int i, + operand_entry_t curr, + operand_entry_t last) +{ + + /* If we have two of the same op, and the opcode is & |, min, or max, + we can eliminate one of them. + If we have two of the same op, and the opcode is ^, we can + eliminate both of them. */ + + if (last && last->op == curr->op) + { + switch (opcode) + { + case MAX_EXPR: + case MIN_EXPR: + case BIT_IOR_EXPR: + case BIT_AND_EXPR: + if (dump_file && (dump_flags & TDF_DETAILS)) + { + fprintf (dump_file, "Equivalence: "); + print_generic_expr (dump_file, curr->op, 0); + fprintf (dump_file, " [&|minmax] "); + print_generic_expr (dump_file, last->op, 0); + fprintf (dump_file, " -> "); + print_generic_stmt (dump_file, last->op, 0); + } + + VEC_ordered_remove (operand_entry_t, *ops, i); + reassociate_stats.ops_eliminated ++; + + return true; + + case BIT_XOR_EXPR: + if (dump_file && (dump_flags & TDF_DETAILS)) + { + fprintf (dump_file, "Equivalence: "); + print_generic_expr (dump_file, curr->op, 0); + fprintf (dump_file, " ^ "); + print_generic_expr (dump_file, last->op, 0); + fprintf (dump_file, " -> nothing\n"); + } + + reassociate_stats.ops_eliminated += 2; + + if (VEC_length (operand_entry_t, *ops) == 2) + { + VEC_free (operand_entry_t, heap, *ops); + *ops = NULL; + add_to_ops_vec (ops, build_zero_cst (TREE_TYPE (last->op))); + *all_done = true; + } + else + { + VEC_ordered_remove (operand_entry_t, *ops, i-1); + VEC_ordered_remove (operand_entry_t, *ops, i-1); + } + + return true; + + default: + break; + } + } + return false; +} + +static VEC(tree, heap) *plus_negates; + +/* If OPCODE is PLUS_EXPR, CURR->OP is a negate expression or a bitwise not + expression, look in OPS for a corresponding positive operation to cancel + it out. If we find one, remove the other from OPS, replace + OPS[CURRINDEX] with 0 or -1, respectively, and return true. Otherwise, + return false. */ + +static bool +eliminate_plus_minus_pair (enum tree_code opcode, + VEC (operand_entry_t, heap) **ops, + unsigned int currindex, + operand_entry_t curr) +{ + tree negateop; + tree notop; + unsigned int i; + operand_entry_t oe; + + if (opcode != PLUS_EXPR || TREE_CODE (curr->op) != SSA_NAME) + return false; + + negateop = get_unary_op (curr->op, NEGATE_EXPR); + notop = get_unary_op (curr->op, BIT_NOT_EXPR); + if (negateop == NULL_TREE && notop == NULL_TREE) + return false; + + /* Any non-negated version will have a rank that is one less than + the current rank. So once we hit those ranks, if we don't find + one, we can stop. */ + + for (i = currindex + 1; + VEC_iterate (operand_entry_t, *ops, i, oe) + && oe->rank >= curr->rank - 1 ; + i++) + { + if (oe->op == negateop) + { + + if (dump_file && (dump_flags & TDF_DETAILS)) + { + fprintf (dump_file, "Equivalence: "); + print_generic_expr (dump_file, negateop, 0); + fprintf (dump_file, " + -"); + print_generic_expr (dump_file, oe->op, 0); + fprintf (dump_file, " -> 0\n"); + } + + VEC_ordered_remove (operand_entry_t, *ops, i); + add_to_ops_vec (ops, build_zero_cst (TREE_TYPE (oe->op))); + VEC_ordered_remove (operand_entry_t, *ops, currindex); + reassociate_stats.ops_eliminated ++; + + return true; + } + else if (oe->op == notop) + { + tree op_type = TREE_TYPE (oe->op); + + if (dump_file && (dump_flags & TDF_DETAILS)) + { + fprintf (dump_file, "Equivalence: "); + print_generic_expr (dump_file, notop, 0); + fprintf (dump_file, " + ~"); + print_generic_expr (dump_file, oe->op, 0); + fprintf (dump_file, " -> -1\n"); + } + + VEC_ordered_remove (operand_entry_t, *ops, i); + add_to_ops_vec (ops, build_int_cst_type (op_type, -1)); + VEC_ordered_remove (operand_entry_t, *ops, currindex); + reassociate_stats.ops_eliminated ++; + + return true; + } + } + + /* CURR->OP is a negate expr in a plus expr: save it for later + inspection in repropagate_negates(). */ + if (negateop != NULL_TREE) + VEC_safe_push (tree, heap, plus_negates, curr->op); + + return false; +} + +/* If OPCODE is BIT_IOR_EXPR, BIT_AND_EXPR, and, CURR->OP is really a + bitwise not expression, look in OPS for a corresponding operand to + cancel it out. If we find one, remove the other from OPS, replace + OPS[CURRINDEX] with 0, and return true. Otherwise, return + false. */ + +static bool +eliminate_not_pairs (enum tree_code opcode, + VEC (operand_entry_t, heap) **ops, + unsigned int currindex, + operand_entry_t curr) +{ + tree notop; + unsigned int i; + operand_entry_t oe; + + if ((opcode != BIT_IOR_EXPR && opcode != BIT_AND_EXPR) + || TREE_CODE (curr->op) != SSA_NAME) + return false; + + notop = get_unary_op (curr->op, BIT_NOT_EXPR); + if (notop == NULL_TREE) + return false; + + /* Any non-not version will have a rank that is one less than + the current rank. So once we hit those ranks, if we don't find + one, we can stop. */ + + for (i = currindex + 1; + VEC_iterate (operand_entry_t, *ops, i, oe) + && oe->rank >= curr->rank - 1; + i++) + { + if (oe->op == notop) + { + if (dump_file && (dump_flags & TDF_DETAILS)) + { + fprintf (dump_file, "Equivalence: "); + print_generic_expr (dump_file, notop, 0); + if (opcode == BIT_AND_EXPR) + fprintf (dump_file, " & ~"); + else if (opcode == BIT_IOR_EXPR) + fprintf (dump_file, " | ~"); + print_generic_expr (dump_file, oe->op, 0); + if (opcode == BIT_AND_EXPR) + fprintf (dump_file, " -> 0\n"); + else if (opcode == BIT_IOR_EXPR) + fprintf (dump_file, " -> -1\n"); + } + + if (opcode == BIT_AND_EXPR) + oe->op = build_zero_cst (TREE_TYPE (oe->op)); + else if (opcode == BIT_IOR_EXPR) + oe->op = build_low_bits_mask (TREE_TYPE (oe->op), + TYPE_PRECISION (TREE_TYPE (oe->op))); + + reassociate_stats.ops_eliminated + += VEC_length (operand_entry_t, *ops) - 1; + VEC_free (operand_entry_t, heap, *ops); + *ops = NULL; + VEC_safe_push (operand_entry_t, heap, *ops, oe); + return true; + } + } + + return false; +} + +/* Use constant value that may be present in OPS to try to eliminate + operands. Note that this function is only really used when we've + eliminated ops for other reasons, or merged constants. Across + single statements, fold already does all of this, plus more. There + is little point in duplicating logic, so I've only included the + identities that I could ever construct testcases to trigger. */ + +static void +eliminate_using_constants (enum tree_code opcode, + VEC(operand_entry_t, heap) **ops) +{ + operand_entry_t oelast = VEC_last (operand_entry_t, *ops); + tree type = TREE_TYPE (oelast->op); + + if (oelast->rank == 0 + && (INTEGRAL_TYPE_P (type) || FLOAT_TYPE_P (type))) + { + switch (opcode) + { + case BIT_AND_EXPR: + if (integer_zerop (oelast->op)) + { + if (VEC_length (operand_entry_t, *ops) != 1) + { + if (dump_file && (dump_flags & TDF_DETAILS)) + fprintf (dump_file, "Found & 0, removing all other ops\n"); + + reassociate_stats.ops_eliminated + += VEC_length (operand_entry_t, *ops) - 1; + + VEC_free (operand_entry_t, heap, *ops); + *ops = NULL; + VEC_safe_push (operand_entry_t, heap, *ops, oelast); + return; + } + } + else if (integer_all_onesp (oelast->op)) + { + if (VEC_length (operand_entry_t, *ops) != 1) + { + if (dump_file && (dump_flags & TDF_DETAILS)) + fprintf (dump_file, "Found & -1, removing\n"); + VEC_pop (operand_entry_t, *ops); + reassociate_stats.ops_eliminated++; + } + } + break; + case BIT_IOR_EXPR: + if (integer_all_onesp (oelast->op)) + { + if (VEC_length (operand_entry_t, *ops) != 1) + { + if (dump_file && (dump_flags & TDF_DETAILS)) + fprintf (dump_file, "Found | -1, removing all other ops\n"); + + reassociate_stats.ops_eliminated + += VEC_length (operand_entry_t, *ops) - 1; + + VEC_free (operand_entry_t, heap, *ops); + *ops = NULL; + VEC_safe_push (operand_entry_t, heap, *ops, oelast); + return; + } + } + else if (integer_zerop (oelast->op)) + { + if (VEC_length (operand_entry_t, *ops) != 1) + { + if (dump_file && (dump_flags & TDF_DETAILS)) + fprintf (dump_file, "Found | 0, removing\n"); + VEC_pop (operand_entry_t, *ops); + reassociate_stats.ops_eliminated++; + } + } + break; + case MULT_EXPR: + if (integer_zerop (oelast->op) + || (FLOAT_TYPE_P (type) + && !HONOR_NANS (TYPE_MODE (type)) + && !HONOR_SIGNED_ZEROS (TYPE_MODE (type)) + && real_zerop (oelast->op))) + { + if (VEC_length (operand_entry_t, *ops) != 1) + { + if (dump_file && (dump_flags & TDF_DETAILS)) + fprintf (dump_file, "Found * 0, removing all other ops\n"); + + reassociate_stats.ops_eliminated + += VEC_length (operand_entry_t, *ops) - 1; + VEC_free (operand_entry_t, heap, *ops); + *ops = NULL; + VEC_safe_push (operand_entry_t, heap, *ops, oelast); + return; + } + } + else if (integer_onep (oelast->op) + || (FLOAT_TYPE_P (type) + && !HONOR_SNANS (TYPE_MODE (type)) + && real_onep (oelast->op))) + { + if (VEC_length (operand_entry_t, *ops) != 1) + { + if (dump_file && (dump_flags & TDF_DETAILS)) + fprintf (dump_file, "Found * 1, removing\n"); + VEC_pop (operand_entry_t, *ops); + reassociate_stats.ops_eliminated++; + return; + } + } + break; + case BIT_XOR_EXPR: + case PLUS_EXPR: + case MINUS_EXPR: + if (integer_zerop (oelast->op) + || (FLOAT_TYPE_P (type) + && (opcode == PLUS_EXPR || opcode == MINUS_EXPR) + && fold_real_zero_addition_p (type, oelast->op, + opcode == MINUS_EXPR))) + { + if (VEC_length (operand_entry_t, *ops) != 1) + { + if (dump_file && (dump_flags & TDF_DETAILS)) + fprintf (dump_file, "Found [|^+] 0, removing\n"); + VEC_pop (operand_entry_t, *ops); + reassociate_stats.ops_eliminated++; + return; + } + } + break; + default: + break; + } + } +} + + +static void linearize_expr_tree (VEC(operand_entry_t, heap) **, gimple, + bool, bool); + +/* Structure for tracking and counting operands. */ +typedef struct oecount_s { + int cnt; + int id; + enum tree_code oecode; + tree op; +} oecount; + +DEF_VEC_O(oecount); +DEF_VEC_ALLOC_O(oecount,heap); + +/* The heap for the oecount hashtable and the sorted list of operands. */ +static VEC (oecount, heap) *cvec; + +/* Hash function for oecount. */ + +static hashval_t +oecount_hash (const void *p) +{ + const oecount *c = VEC_index (oecount, cvec, (size_t)p - 42); + return htab_hash_pointer (c->op) ^ (hashval_t)c->oecode; +} + +/* Comparison function for oecount. */ + +static int +oecount_eq (const void *p1, const void *p2) +{ + const oecount *c1 = VEC_index (oecount, cvec, (size_t)p1 - 42); + const oecount *c2 = VEC_index (oecount, cvec, (size_t)p2 - 42); + return (c1->oecode == c2->oecode + && c1->op == c2->op); +} + +/* Comparison function for qsort sorting oecount elements by count. */ + +static int +oecount_cmp (const void *p1, const void *p2) +{ + const oecount *c1 = (const oecount *)p1; + const oecount *c2 = (const oecount *)p2; + if (c1->cnt != c2->cnt) + return c1->cnt - c2->cnt; + else + /* If counts are identical, use unique IDs to stabilize qsort. */ + return c1->id - c2->id; +} + +/* Walks the linear chain with result *DEF searching for an operation + with operand OP and code OPCODE removing that from the chain. *DEF + is updated if there is only one operand but no operation left. */ + +static void +zero_one_operation (tree *def, enum tree_code opcode, tree op) +{ + gimple stmt = SSA_NAME_DEF_STMT (*def); + + do + { + tree name = gimple_assign_rhs1 (stmt); + + /* If this is the operation we look for and one of the operands + is ours simply propagate the other operand into the stmts + single use. */ + if (gimple_assign_rhs_code (stmt) == opcode + && (name == op + || gimple_assign_rhs2 (stmt) == op)) + { + gimple use_stmt; + use_operand_p use; + gimple_stmt_iterator gsi; + if (name == op) + name = gimple_assign_rhs2 (stmt); + gcc_assert (has_single_use (gimple_assign_lhs (stmt))); + single_imm_use (gimple_assign_lhs (stmt), &use, &use_stmt); + if (gimple_assign_lhs (stmt) == *def) + *def = name; + SET_USE (use, name); + if (TREE_CODE (name) != SSA_NAME) + update_stmt (use_stmt); + gsi = gsi_for_stmt (stmt); + gsi_remove (&gsi, true); + release_defs (stmt); + return; + } + + /* Continue walking the chain. */ + gcc_assert (name != op + && TREE_CODE (name) == SSA_NAME); + stmt = SSA_NAME_DEF_STMT (name); + } + while (1); +} + +/* Builds one statement performing OP1 OPCODE OP2 using TMPVAR for + the result. Places the statement after the definition of either + OP1 or OP2. Returns the new statement. */ + +static gimple +build_and_add_sum (tree tmpvar, tree op1, tree op2, enum tree_code opcode) +{ + gimple op1def = NULL, op2def = NULL; + gimple_stmt_iterator gsi; + tree op; + gimple sum; + + /* Create the addition statement. */ + sum = gimple_build_assign_with_ops (opcode, tmpvar, op1, op2); + op = make_ssa_name (tmpvar, sum); + gimple_assign_set_lhs (sum, op); + + /* Find an insertion place and insert. */ + if (TREE_CODE (op1) == SSA_NAME) + op1def = SSA_NAME_DEF_STMT (op1); + if (TREE_CODE (op2) == SSA_NAME) + op2def = SSA_NAME_DEF_STMT (op2); + if ((!op1def || gimple_nop_p (op1def)) + && (!op2def || gimple_nop_p (op2def))) + { + gsi = gsi_after_labels (single_succ (ENTRY_BLOCK_PTR)); + gsi_insert_before (&gsi, sum, GSI_NEW_STMT); + } + else if ((!op1def || gimple_nop_p (op1def)) + || (op2def && !gimple_nop_p (op2def) + && stmt_dominates_stmt_p (op1def, op2def))) + { + if (gimple_code (op2def) == GIMPLE_PHI) + { + gsi = gsi_after_labels (gimple_bb (op2def)); + gsi_insert_before (&gsi, sum, GSI_NEW_STMT); + } + else + { + if (!stmt_ends_bb_p (op2def)) + { + gsi = gsi_for_stmt (op2def); + gsi_insert_after (&gsi, sum, GSI_NEW_STMT); + } + else + { + edge e; + edge_iterator ei; + + FOR_EACH_EDGE (e, ei, gimple_bb (op2def)->succs) + if (e->flags & EDGE_FALLTHRU) + gsi_insert_on_edge_immediate (e, sum); + } + } + } + else + { + if (gimple_code (op1def) == GIMPLE_PHI) + { + gsi = gsi_after_labels (gimple_bb (op1def)); + gsi_insert_before (&gsi, sum, GSI_NEW_STMT); + } + else + { + if (!stmt_ends_bb_p (op1def)) + { + gsi = gsi_for_stmt (op1def); + gsi_insert_after (&gsi, sum, GSI_NEW_STMT); + } + else + { + edge e; + edge_iterator ei; + + FOR_EACH_EDGE (e, ei, gimple_bb (op1def)->succs) + if (e->flags & EDGE_FALLTHRU) + gsi_insert_on_edge_immediate (e, sum); + } + } + } + update_stmt (sum); + + return sum; +} + +/* Perform un-distribution of divisions and multiplications. + A * X + B * X is transformed into (A + B) * X and A / X + B / X + to (A + B) / X for real X. + + The algorithm is organized as follows. + + - First we walk the addition chain *OPS looking for summands that + are defined by a multiplication or a real division. This results + in the candidates bitmap with relevant indices into *OPS. + + - Second we build the chains of multiplications or divisions for + these candidates, counting the number of occurences of (operand, code) + pairs in all of the candidates chains. + + - Third we sort the (operand, code) pairs by number of occurence and + process them starting with the pair with the most uses. + + * For each such pair we walk the candidates again to build a + second candidate bitmap noting all multiplication/division chains + that have at least one occurence of (operand, code). + + * We build an alternate addition chain only covering these + candidates with one (operand, code) operation removed from their + multiplication/division chain. + + * The first candidate gets replaced by the alternate addition chain + multiplied/divided by the operand. + + * All candidate chains get disabled for further processing and + processing of (operand, code) pairs continues. + + The alternate addition chains built are re-processed by the main + reassociation algorithm which allows optimizing a * x * y + b * y * x + to (a + b ) * x * y in one invocation of the reassociation pass. */ + +static bool +undistribute_ops_list (enum tree_code opcode, + VEC (operand_entry_t, heap) **ops, struct loop *loop) +{ + unsigned int length = VEC_length (operand_entry_t, *ops); + operand_entry_t oe1; + unsigned i, j; + sbitmap candidates, candidates2; + unsigned nr_candidates, nr_candidates2; + sbitmap_iterator sbi0; + VEC (operand_entry_t, heap) **subops; + htab_t ctable; + bool changed = false; + int next_oecount_id = 0; + + if (length <= 1 + || opcode != PLUS_EXPR) + return false; + + /* Build a list of candidates to process. */ + candidates = sbitmap_alloc (length); + sbitmap_zero (candidates); + nr_candidates = 0; + FOR_EACH_VEC_ELT (operand_entry_t, *ops, i, oe1) + { + enum tree_code dcode; + gimple oe1def; + + if (TREE_CODE (oe1->op) != SSA_NAME) + continue; + oe1def = SSA_NAME_DEF_STMT (oe1->op); + if (!is_gimple_assign (oe1def)) + continue; + dcode = gimple_assign_rhs_code (oe1def); + if ((dcode != MULT_EXPR + && dcode != RDIV_EXPR) + || !is_reassociable_op (oe1def, dcode, loop)) + continue; + + SET_BIT (candidates, i); + nr_candidates++; + } + + if (nr_candidates < 2) + { + sbitmap_free (candidates); + return false; + } + + if (dump_file && (dump_flags & TDF_DETAILS)) + { + fprintf (dump_file, "searching for un-distribute opportunities "); + print_generic_expr (dump_file, + VEC_index (operand_entry_t, *ops, + sbitmap_first_set_bit (candidates))->op, 0); + fprintf (dump_file, " %d\n", nr_candidates); + } + + /* Build linearized sub-operand lists and the counting table. */ + cvec = NULL; + ctable = htab_create (15, oecount_hash, oecount_eq, NULL); + subops = XCNEWVEC (VEC (operand_entry_t, heap) *, + VEC_length (operand_entry_t, *ops)); + EXECUTE_IF_SET_IN_SBITMAP (candidates, 0, i, sbi0) + { + gimple oedef; + enum tree_code oecode; + unsigned j; + + oedef = SSA_NAME_DEF_STMT (VEC_index (operand_entry_t, *ops, i)->op); + oecode = gimple_assign_rhs_code (oedef); + linearize_expr_tree (&subops[i], oedef, + associative_tree_code (oecode), false); + + FOR_EACH_VEC_ELT (operand_entry_t, subops[i], j, oe1) + { + oecount c; + void **slot; + size_t idx; + c.oecode = oecode; + c.cnt = 1; + c.id = next_oecount_id++; + c.op = oe1->op; + VEC_safe_push (oecount, heap, cvec, &c); + idx = VEC_length (oecount, cvec) + 41; + slot = htab_find_slot (ctable, (void *)idx, INSERT); + if (!*slot) + { + *slot = (void *)idx; + } + else + { + VEC_pop (oecount, cvec); + VEC_index (oecount, cvec, (size_t)*slot - 42)->cnt++; + } + } + } + htab_delete (ctable); + + /* Sort the counting table. */ + VEC_qsort (oecount, cvec, oecount_cmp); + + if (dump_file && (dump_flags & TDF_DETAILS)) + { + oecount *c; + fprintf (dump_file, "Candidates:\n"); + FOR_EACH_VEC_ELT (oecount, cvec, j, c) + { + fprintf (dump_file, " %u %s: ", c->cnt, + c->oecode == MULT_EXPR + ? "*" : c->oecode == RDIV_EXPR ? "/" : "?"); + print_generic_expr (dump_file, c->op, 0); + fprintf (dump_file, "\n"); + } + } + + /* Process the (operand, code) pairs in order of most occurence. */ + candidates2 = sbitmap_alloc (length); + while (!VEC_empty (oecount, cvec)) + { + oecount *c = VEC_last (oecount, cvec); + if (c->cnt < 2) + break; + + /* Now collect the operands in the outer chain that contain + the common operand in their inner chain. */ + sbitmap_zero (candidates2); + nr_candidates2 = 0; + EXECUTE_IF_SET_IN_SBITMAP (candidates, 0, i, sbi0) + { + gimple oedef; + enum tree_code oecode; + unsigned j; + tree op = VEC_index (operand_entry_t, *ops, i)->op; + + /* If we undistributed in this chain already this may be + a constant. */ + if (TREE_CODE (op) != SSA_NAME) + continue; + + oedef = SSA_NAME_DEF_STMT (op); + oecode = gimple_assign_rhs_code (oedef); + if (oecode != c->oecode) + continue; + + FOR_EACH_VEC_ELT (operand_entry_t, subops[i], j, oe1) + { + if (oe1->op == c->op) + { + SET_BIT (candidates2, i); + ++nr_candidates2; + break; + } + } + } + + if (nr_candidates2 >= 2) + { + operand_entry_t oe1, oe2; + tree tmpvar; + gimple prod; + int first = sbitmap_first_set_bit (candidates2); + + /* Build the new addition chain. */ + oe1 = VEC_index (operand_entry_t, *ops, first); + if (dump_file && (dump_flags & TDF_DETAILS)) + { + fprintf (dump_file, "Building ("); + print_generic_expr (dump_file, oe1->op, 0); + } + tmpvar = create_tmp_reg (TREE_TYPE (oe1->op), NULL); + add_referenced_var (tmpvar); + zero_one_operation (&oe1->op, c->oecode, c->op); + EXECUTE_IF_SET_IN_SBITMAP (candidates2, first+1, i, sbi0) + { + gimple sum; + oe2 = VEC_index (operand_entry_t, *ops, i); + if (dump_file && (dump_flags & TDF_DETAILS)) + { + fprintf (dump_file, " + "); + print_generic_expr (dump_file, oe2->op, 0); + } + zero_one_operation (&oe2->op, c->oecode, c->op); + sum = build_and_add_sum (tmpvar, oe1->op, oe2->op, opcode); + oe2->op = build_zero_cst (TREE_TYPE (oe2->op)); + oe2->rank = 0; + oe1->op = gimple_get_lhs (sum); + } + + /* Apply the multiplication/division. */ + prod = build_and_add_sum (tmpvar, oe1->op, c->op, c->oecode); + if (dump_file && (dump_flags & TDF_DETAILS)) + { + fprintf (dump_file, ") %s ", c->oecode == MULT_EXPR ? "*" : "/"); + print_generic_expr (dump_file, c->op, 0); + fprintf (dump_file, "\n"); + } + + /* Record it in the addition chain and disable further + undistribution with this op. */ + oe1->op = gimple_assign_lhs (prod); + oe1->rank = get_rank (oe1->op); + VEC_free (operand_entry_t, heap, subops[first]); + + changed = true; + } + + VEC_pop (oecount, cvec); + } + + for (i = 0; i < VEC_length (operand_entry_t, *ops); ++i) + VEC_free (operand_entry_t, heap, subops[i]); + free (subops); + VEC_free (oecount, heap, cvec); + sbitmap_free (candidates); + sbitmap_free (candidates2); + + return changed; +} + +/* If OPCODE is BIT_IOR_EXPR or BIT_AND_EXPR and CURR is a comparison + expression, examine the other OPS to see if any of them are comparisons + of the same values, which we may be able to combine or eliminate. + For example, we can rewrite (a < b) | (a == b) as (a <= b). */ + +static bool +eliminate_redundant_comparison (enum tree_code opcode, + VEC (operand_entry_t, heap) **ops, + unsigned int currindex, + operand_entry_t curr) +{ + tree op1, op2; + enum tree_code lcode, rcode; + gimple def1, def2; + int i; + operand_entry_t oe; + + if (opcode != BIT_IOR_EXPR && opcode != BIT_AND_EXPR) + return false; + + /* Check that CURR is a comparison. */ + if (TREE_CODE (curr->op) != SSA_NAME) + return false; + def1 = SSA_NAME_DEF_STMT (curr->op); + if (!is_gimple_assign (def1)) + return false; + lcode = gimple_assign_rhs_code (def1); + if (TREE_CODE_CLASS (lcode) != tcc_comparison) + return false; + op1 = gimple_assign_rhs1 (def1); + op2 = gimple_assign_rhs2 (def1); + + /* Now look for a similar comparison in the remaining OPS. */ + for (i = currindex + 1; + VEC_iterate (operand_entry_t, *ops, i, oe); + i++) + { + tree t; + + if (TREE_CODE (oe->op) != SSA_NAME) + continue; + def2 = SSA_NAME_DEF_STMT (oe->op); + if (!is_gimple_assign (def2)) + continue; + rcode = gimple_assign_rhs_code (def2); + if (TREE_CODE_CLASS (rcode) != tcc_comparison) + continue; + + /* If we got here, we have a match. See if we can combine the + two comparisons. */ + if (opcode == BIT_IOR_EXPR) + t = maybe_fold_or_comparisons (lcode, op1, op2, + rcode, gimple_assign_rhs1 (def2), + gimple_assign_rhs2 (def2)); + else + t = maybe_fold_and_comparisons (lcode, op1, op2, + rcode, gimple_assign_rhs1 (def2), + gimple_assign_rhs2 (def2)); + if (!t) + continue; + + /* maybe_fold_and_comparisons and maybe_fold_or_comparisons + always give us a boolean_type_node value back. If the original + BIT_AND_EXPR or BIT_IOR_EXPR was of a wider integer type, + we need to convert. */ + if (!useless_type_conversion_p (TREE_TYPE (curr->op), TREE_TYPE (t))) + t = fold_convert (TREE_TYPE (curr->op), t); + + if (TREE_CODE (t) != INTEGER_CST + && !operand_equal_p (t, curr->op, 0)) + { + enum tree_code subcode; + tree newop1, newop2; + if (!COMPARISON_CLASS_P (t)) + continue; + extract_ops_from_tree (t, &subcode, &newop1, &newop2); + STRIP_USELESS_TYPE_CONVERSION (newop1); + STRIP_USELESS_TYPE_CONVERSION (newop2); + if (!is_gimple_val (newop1) || !is_gimple_val (newop2)) + continue; + } + + if (dump_file && (dump_flags & TDF_DETAILS)) + { + fprintf (dump_file, "Equivalence: "); + print_generic_expr (dump_file, curr->op, 0); + fprintf (dump_file, " %s ", op_symbol_code (opcode)); + print_generic_expr (dump_file, oe->op, 0); + fprintf (dump_file, " -> "); + print_generic_expr (dump_file, t, 0); + fprintf (dump_file, "\n"); + } + + /* Now we can delete oe, as it has been subsumed by the new combined + expression t. */ + VEC_ordered_remove (operand_entry_t, *ops, i); + reassociate_stats.ops_eliminated ++; + + /* If t is the same as curr->op, we're done. Otherwise we must + replace curr->op with t. Special case is if we got a constant + back, in which case we add it to the end instead of in place of + the current entry. */ + if (TREE_CODE (t) == INTEGER_CST) + { + VEC_ordered_remove (operand_entry_t, *ops, currindex); + add_to_ops_vec (ops, t); + } + else if (!operand_equal_p (t, curr->op, 0)) + { + tree tmpvar; + gimple sum; + enum tree_code subcode; + tree newop1; + tree newop2; + gcc_assert (COMPARISON_CLASS_P (t)); + tmpvar = create_tmp_var (TREE_TYPE (t), NULL); + add_referenced_var (tmpvar); + extract_ops_from_tree (t, &subcode, &newop1, &newop2); + STRIP_USELESS_TYPE_CONVERSION (newop1); + STRIP_USELESS_TYPE_CONVERSION (newop2); + gcc_checking_assert (is_gimple_val (newop1) + && is_gimple_val (newop2)); + sum = build_and_add_sum (tmpvar, newop1, newop2, subcode); + curr->op = gimple_get_lhs (sum); + } + return true; + } + + return false; +} + +/* Perform various identities and other optimizations on the list of + operand entries, stored in OPS. The tree code for the binary + operation between all the operands is OPCODE. */ + +static void +optimize_ops_list (enum tree_code opcode, + VEC (operand_entry_t, heap) **ops) +{ + unsigned int length = VEC_length (operand_entry_t, *ops); + unsigned int i; + operand_entry_t oe; + operand_entry_t oelast = NULL; + bool iterate = false; + + if (length == 1) + return; + + oelast = VEC_last (operand_entry_t, *ops); + + /* If the last two are constants, pop the constants off, merge them + and try the next two. */ + if (oelast->rank == 0 && is_gimple_min_invariant (oelast->op)) + { + operand_entry_t oelm1 = VEC_index (operand_entry_t, *ops, length - 2); + + if (oelm1->rank == 0 + && is_gimple_min_invariant (oelm1->op) + && useless_type_conversion_p (TREE_TYPE (oelm1->op), + TREE_TYPE (oelast->op))) + { + tree folded = fold_binary (opcode, TREE_TYPE (oelm1->op), + oelm1->op, oelast->op); + + if (folded && is_gimple_min_invariant (folded)) + { + if (dump_file && (dump_flags & TDF_DETAILS)) + fprintf (dump_file, "Merging constants\n"); + + VEC_pop (operand_entry_t, *ops); + VEC_pop (operand_entry_t, *ops); + + add_to_ops_vec (ops, folded); + reassociate_stats.constants_eliminated++; + + optimize_ops_list (opcode, ops); + return; + } + } + } + + eliminate_using_constants (opcode, ops); + oelast = NULL; + + for (i = 0; VEC_iterate (operand_entry_t, *ops, i, oe);) + { + bool done = false; + + if (eliminate_not_pairs (opcode, ops, i, oe)) + return; + if (eliminate_duplicate_pair (opcode, ops, &done, i, oe, oelast) + || (!done && eliminate_plus_minus_pair (opcode, ops, i, oe)) + || (!done && eliminate_redundant_comparison (opcode, ops, i, oe))) + { + if (done) + return; + iterate = true; + oelast = NULL; + continue; + } + oelast = oe; + i++; + } + + length = VEC_length (operand_entry_t, *ops); + oelast = VEC_last (operand_entry_t, *ops); + + if (iterate) + optimize_ops_list (opcode, ops); +} + +/* Return true if OPERAND is defined by a PHI node which uses the LHS + of STMT in it's operands. This is also known as a "destructive + update" operation. */ + +static bool +is_phi_for_stmt (gimple stmt, tree operand) +{ + gimple def_stmt; + tree lhs; + use_operand_p arg_p; + ssa_op_iter i; + + if (TREE_CODE (operand) != SSA_NAME) + return false; + + lhs = gimple_assign_lhs (stmt); + + def_stmt = SSA_NAME_DEF_STMT (operand); + if (gimple_code (def_stmt) != GIMPLE_PHI) + return false; + + FOR_EACH_PHI_ARG (arg_p, def_stmt, i, SSA_OP_USE) + if (lhs == USE_FROM_PTR (arg_p)) + return true; + return false; +} + +/* Remove def stmt of VAR if VAR has zero uses and recurse + on rhs1 operand if so. */ + +static void +remove_visited_stmt_chain (tree var) +{ + gimple stmt; + gimple_stmt_iterator gsi; + + while (1) + { + if (TREE_CODE (var) != SSA_NAME || !has_zero_uses (var)) + return; + stmt = SSA_NAME_DEF_STMT (var); + if (!is_gimple_assign (stmt) + || !gimple_visited_p (stmt)) + return; + var = gimple_assign_rhs1 (stmt); + gsi = gsi_for_stmt (stmt); + gsi_remove (&gsi, true); + release_defs (stmt); + } +} + +/* Recursively rewrite our linearized statements so that the operators + match those in OPS[OPINDEX], putting the computation in rank + order. */ + +static void +rewrite_expr_tree (gimple stmt, unsigned int opindex, + VEC(operand_entry_t, heap) * ops, bool moved) +{ + tree rhs1 = gimple_assign_rhs1 (stmt); + tree rhs2 = gimple_assign_rhs2 (stmt); + operand_entry_t oe; + + /* If we have three operands left, then we want to make sure the one + that gets the double binary op are the ones with the same rank. + + The alternative we try is to see if this is a destructive + update style statement, which is like: + b = phi (a, ...) + a = c + b; + In that case, we want to use the destructive update form to + expose the possible vectorizer sum reduction opportunity. + In that case, the third operand will be the phi node. + + We could, of course, try to be better as noted above, and do a + lot of work to try to find these opportunities in >3 operand + cases, but it is unlikely to be worth it. */ + if (opindex + 3 == VEC_length (operand_entry_t, ops)) + { + operand_entry_t oe1, oe2, oe3; + + oe1 = VEC_index (operand_entry_t, ops, opindex); + oe2 = VEC_index (operand_entry_t, ops, opindex + 1); + oe3 = VEC_index (operand_entry_t, ops, opindex + 2); + + if ((oe1->rank == oe2->rank + && oe2->rank != oe3->rank) + || (is_phi_for_stmt (stmt, oe3->op) + && !is_phi_for_stmt (stmt, oe1->op) + && !is_phi_for_stmt (stmt, oe2->op))) + { + struct operand_entry temp = *oe3; + oe3->op = oe1->op; + oe3->rank = oe1->rank; + oe1->op = temp.op; + oe1->rank= temp.rank; + } + else if ((oe1->rank == oe3->rank + && oe2->rank != oe3->rank) + || (is_phi_for_stmt (stmt, oe2->op) + && !is_phi_for_stmt (stmt, oe1->op) + && !is_phi_for_stmt (stmt, oe3->op))) + { + struct operand_entry temp = *oe2; + oe2->op = oe1->op; + oe2->rank = oe1->rank; + oe1->op = temp.op; + oe1->rank= temp.rank; + } + } + + /* The final recursion case for this function is that you have + exactly two operations left. + If we had one exactly one op in the entire list to start with, we + would have never called this function, and the tail recursion + rewrites them one at a time. */ + if (opindex + 2 == VEC_length (operand_entry_t, ops)) + { + operand_entry_t oe1, oe2; + + oe1 = VEC_index (operand_entry_t, ops, opindex); + oe2 = VEC_index (operand_entry_t, ops, opindex + 1); + + if (rhs1 != oe1->op || rhs2 != oe2->op) + { + if (dump_file && (dump_flags & TDF_DETAILS)) + { + fprintf (dump_file, "Transforming "); + print_gimple_stmt (dump_file, stmt, 0, 0); + } + + gimple_assign_set_rhs1 (stmt, oe1->op); + gimple_assign_set_rhs2 (stmt, oe2->op); + update_stmt (stmt); + if (rhs1 != oe1->op && rhs1 != oe2->op) + remove_visited_stmt_chain (rhs1); + + if (dump_file && (dump_flags & TDF_DETAILS)) + { + fprintf (dump_file, " into "); + print_gimple_stmt (dump_file, stmt, 0, 0); + } + + } + return; + } + + /* If we hit here, we should have 3 or more ops left. */ + gcc_assert (opindex + 2 < VEC_length (operand_entry_t, ops)); + + /* Rewrite the next operator. */ + oe = VEC_index (operand_entry_t, ops, opindex); + + if (oe->op != rhs2) + { + if (!moved) + { + gimple_stmt_iterator gsinow, gsirhs1; + gimple stmt1 = stmt, stmt2; + unsigned int count; + + gsinow = gsi_for_stmt (stmt); + count = VEC_length (operand_entry_t, ops) - opindex - 2; + while (count-- != 0) + { + stmt2 = SSA_NAME_DEF_STMT (gimple_assign_rhs1 (stmt1)); + gsirhs1 = gsi_for_stmt (stmt2); + gsi_move_before (&gsirhs1, &gsinow); + gsi_prev (&gsinow); + stmt1 = stmt2; + } + moved = true; + } + + if (dump_file && (dump_flags & TDF_DETAILS)) + { + fprintf (dump_file, "Transforming "); + print_gimple_stmt (dump_file, stmt, 0, 0); + } + + gimple_assign_set_rhs2 (stmt, oe->op); + update_stmt (stmt); + + if (dump_file && (dump_flags & TDF_DETAILS)) + { + fprintf (dump_file, " into "); + print_gimple_stmt (dump_file, stmt, 0, 0); + } + } + /* Recurse on the LHS of the binary operator, which is guaranteed to + be the non-leaf side. */ + rewrite_expr_tree (SSA_NAME_DEF_STMT (rhs1), opindex + 1, ops, moved); +} + +/* Transform STMT, which is really (A +B) + (C + D) into the left + linear form, ((A+B)+C)+D. + Recurse on D if necessary. */ + +static void +linearize_expr (gimple stmt) +{ + gimple_stmt_iterator gsinow, gsirhs; + gimple binlhs = SSA_NAME_DEF_STMT (gimple_assign_rhs1 (stmt)); + gimple binrhs = SSA_NAME_DEF_STMT (gimple_assign_rhs2 (stmt)); + enum tree_code rhscode = gimple_assign_rhs_code (stmt); + gimple newbinrhs = NULL; + struct loop *loop = loop_containing_stmt (stmt); + + gcc_assert (is_reassociable_op (binlhs, rhscode, loop) + && is_reassociable_op (binrhs, rhscode, loop)); + + gsinow = gsi_for_stmt (stmt); + gsirhs = gsi_for_stmt (binrhs); + gsi_move_before (&gsirhs, &gsinow); + + gimple_assign_set_rhs2 (stmt, gimple_assign_rhs1 (binrhs)); + gimple_assign_set_rhs1 (binrhs, gimple_assign_lhs (binlhs)); + gimple_assign_set_rhs1 (stmt, gimple_assign_lhs (binrhs)); + + if (TREE_CODE (gimple_assign_rhs2 (stmt)) == SSA_NAME) + newbinrhs = SSA_NAME_DEF_STMT (gimple_assign_rhs2 (stmt)); + + if (dump_file && (dump_flags & TDF_DETAILS)) + { + fprintf (dump_file, "Linearized: "); + print_gimple_stmt (dump_file, stmt, 0, 0); + } + + reassociate_stats.linearized++; + update_stmt (binrhs); + update_stmt (binlhs); + update_stmt (stmt); + + gimple_set_visited (stmt, true); + gimple_set_visited (binlhs, true); + gimple_set_visited (binrhs, true); + + /* Tail recurse on the new rhs if it still needs reassociation. */ + if (newbinrhs && is_reassociable_op (newbinrhs, rhscode, loop)) + /* ??? This should probably be linearize_expr (newbinrhs) but I don't + want to change the algorithm while converting to tuples. */ + linearize_expr (stmt); +} + +/* If LHS has a single immediate use that is a GIMPLE_ASSIGN statement, return + it. Otherwise, return NULL. */ + +static gimple +get_single_immediate_use (tree lhs) +{ + use_operand_p immuse; + gimple immusestmt; + + if (TREE_CODE (lhs) == SSA_NAME + && single_imm_use (lhs, &immuse, &immusestmt) + && is_gimple_assign (immusestmt)) + return immusestmt; + + return NULL; +} + +/* Recursively negate the value of TONEGATE, and return the SSA_NAME + representing the negated value. Insertions of any necessary + instructions go before GSI. + This function is recursive in that, if you hand it "a_5" as the + value to negate, and a_5 is defined by "a_5 = b_3 + b_4", it will + transform b_3 + b_4 into a_5 = -b_3 + -b_4. */ + +static tree +negate_value (tree tonegate, gimple_stmt_iterator *gsi) +{ + gimple negatedefstmt= NULL; + tree resultofnegate; + + /* If we are trying to negate a name, defined by an add, negate the + add operands instead. */ + if (TREE_CODE (tonegate) == SSA_NAME) + negatedefstmt = SSA_NAME_DEF_STMT (tonegate); + if (TREE_CODE (tonegate) == SSA_NAME + && is_gimple_assign (negatedefstmt) + && TREE_CODE (gimple_assign_lhs (negatedefstmt)) == SSA_NAME + && has_single_use (gimple_assign_lhs (negatedefstmt)) + && gimple_assign_rhs_code (negatedefstmt) == PLUS_EXPR) + { + gimple_stmt_iterator gsi; + tree rhs1 = gimple_assign_rhs1 (negatedefstmt); + tree rhs2 = gimple_assign_rhs2 (negatedefstmt); + + gsi = gsi_for_stmt (negatedefstmt); + rhs1 = negate_value (rhs1, &gsi); + gimple_assign_set_rhs1 (negatedefstmt, rhs1); + + gsi = gsi_for_stmt (negatedefstmt); + rhs2 = negate_value (rhs2, &gsi); + gimple_assign_set_rhs2 (negatedefstmt, rhs2); + + update_stmt (negatedefstmt); + return gimple_assign_lhs (negatedefstmt); + } + + tonegate = fold_build1 (NEGATE_EXPR, TREE_TYPE (tonegate), tonegate); + resultofnegate = force_gimple_operand_gsi (gsi, tonegate, true, + NULL_TREE, true, GSI_SAME_STMT); + return resultofnegate; +} + +/* Return true if we should break up the subtract in STMT into an add + with negate. This is true when we the subtract operands are really + adds, or the subtract itself is used in an add expression. In + either case, breaking up the subtract into an add with negate + exposes the adds to reassociation. */ + +static bool +should_break_up_subtract (gimple stmt) +{ + tree lhs = gimple_assign_lhs (stmt); + tree binlhs = gimple_assign_rhs1 (stmt); + tree binrhs = gimple_assign_rhs2 (stmt); + gimple immusestmt; + struct loop *loop = loop_containing_stmt (stmt); + + if (TREE_CODE (binlhs) == SSA_NAME + && is_reassociable_op (SSA_NAME_DEF_STMT (binlhs), PLUS_EXPR, loop)) + return true; + + if (TREE_CODE (binrhs) == SSA_NAME + && is_reassociable_op (SSA_NAME_DEF_STMT (binrhs), PLUS_EXPR, loop)) + return true; + + if (TREE_CODE (lhs) == SSA_NAME + && (immusestmt = get_single_immediate_use (lhs)) + && is_gimple_assign (immusestmt) + && (gimple_assign_rhs_code (immusestmt) == PLUS_EXPR + || gimple_assign_rhs_code (immusestmt) == MULT_EXPR)) + return true; + return false; +} + +/* Transform STMT from A - B into A + -B. */ + +static void +break_up_subtract (gimple stmt, gimple_stmt_iterator *gsip) +{ + tree rhs1 = gimple_assign_rhs1 (stmt); + tree rhs2 = gimple_assign_rhs2 (stmt); + + if (dump_file && (dump_flags & TDF_DETAILS)) + { + fprintf (dump_file, "Breaking up subtract "); + print_gimple_stmt (dump_file, stmt, 0, 0); + } + + rhs2 = negate_value (rhs2, gsip); + gimple_assign_set_rhs_with_ops (gsip, PLUS_EXPR, rhs1, rhs2); + update_stmt (stmt); +} + +/* Recursively linearize a binary expression that is the RHS of STMT. + Place the operands of the expression tree in the vector named OPS. */ + +static void +linearize_expr_tree (VEC(operand_entry_t, heap) **ops, gimple stmt, + bool is_associative, bool set_visited) +{ + tree binlhs = gimple_assign_rhs1 (stmt); + tree binrhs = gimple_assign_rhs2 (stmt); + gimple binlhsdef, binrhsdef; + bool binlhsisreassoc = false; + bool binrhsisreassoc = false; + enum tree_code rhscode = gimple_assign_rhs_code (stmt); + struct loop *loop = loop_containing_stmt (stmt); + + if (set_visited) + gimple_set_visited (stmt, true); + + if (TREE_CODE (binlhs) == SSA_NAME) + { + binlhsdef = SSA_NAME_DEF_STMT (binlhs); + binlhsisreassoc = (is_reassociable_op (binlhsdef, rhscode, loop) + && !stmt_could_throw_p (binlhsdef)); + } + + if (TREE_CODE (binrhs) == SSA_NAME) + { + binrhsdef = SSA_NAME_DEF_STMT (binrhs); + binrhsisreassoc = (is_reassociable_op (binrhsdef, rhscode, loop) + && !stmt_could_throw_p (binrhsdef)); + } + + /* If the LHS is not reassociable, but the RHS is, we need to swap + them. If neither is reassociable, there is nothing we can do, so + just put them in the ops vector. If the LHS is reassociable, + linearize it. If both are reassociable, then linearize the RHS + and the LHS. */ + + if (!binlhsisreassoc) + { + tree temp; + + /* If this is not a associative operation like division, give up. */ + if (!is_associative) + { + add_to_ops_vec (ops, binrhs); + return; + } + + if (!binrhsisreassoc) + { + add_to_ops_vec (ops, binrhs); + add_to_ops_vec (ops, binlhs); + return; + } + + if (dump_file && (dump_flags & TDF_DETAILS)) + { + fprintf (dump_file, "swapping operands of "); + print_gimple_stmt (dump_file, stmt, 0, 0); + } + + swap_tree_operands (stmt, + gimple_assign_rhs1_ptr (stmt), + gimple_assign_rhs2_ptr (stmt)); + update_stmt (stmt); + + if (dump_file && (dump_flags & TDF_DETAILS)) + { + fprintf (dump_file, " is now "); + print_gimple_stmt (dump_file, stmt, 0, 0); + } + + /* We want to make it so the lhs is always the reassociative op, + so swap. */ + temp = binlhs; + binlhs = binrhs; + binrhs = temp; + } + else if (binrhsisreassoc) + { + linearize_expr (stmt); + binlhs = gimple_assign_rhs1 (stmt); + binrhs = gimple_assign_rhs2 (stmt); + } + + gcc_assert (TREE_CODE (binrhs) != SSA_NAME + || !is_reassociable_op (SSA_NAME_DEF_STMT (binrhs), + rhscode, loop)); + linearize_expr_tree (ops, SSA_NAME_DEF_STMT (binlhs), + is_associative, set_visited); + add_to_ops_vec (ops, binrhs); +} + +/* Repropagate the negates back into subtracts, since no other pass + currently does it. */ + +static void +repropagate_negates (void) +{ + unsigned int i = 0; + tree negate; + + FOR_EACH_VEC_ELT (tree, plus_negates, i, negate) + { + gimple user = get_single_immediate_use (negate); + + if (!user || !is_gimple_assign (user)) + continue; + + /* The negate operand can be either operand of a PLUS_EXPR + (it can be the LHS if the RHS is a constant for example). + + Force the negate operand to the RHS of the PLUS_EXPR, then + transform the PLUS_EXPR into a MINUS_EXPR. */ + if (gimple_assign_rhs_code (user) == PLUS_EXPR) + { + /* If the negated operand appears on the LHS of the + PLUS_EXPR, exchange the operands of the PLUS_EXPR + to force the negated operand to the RHS of the PLUS_EXPR. */ + if (gimple_assign_rhs1 (user) == negate) + { + swap_tree_operands (user, + gimple_assign_rhs1_ptr (user), + gimple_assign_rhs2_ptr (user)); + } + + /* Now transform the PLUS_EXPR into a MINUS_EXPR and replace + the RHS of the PLUS_EXPR with the operand of the NEGATE_EXPR. */ + if (gimple_assign_rhs2 (user) == negate) + { + tree rhs1 = gimple_assign_rhs1 (user); + tree rhs2 = get_unary_op (negate, NEGATE_EXPR); + gimple_stmt_iterator gsi = gsi_for_stmt (user); + gimple_assign_set_rhs_with_ops (&gsi, MINUS_EXPR, rhs1, rhs2); + update_stmt (user); + } + } + else if (gimple_assign_rhs_code (user) == MINUS_EXPR) + { + if (gimple_assign_rhs1 (user) == negate) + { + /* We have + x = -a + y = x - b + which we transform into + x = a + b + y = -x . + This pushes down the negate which we possibly can merge + into some other operation, hence insert it into the + plus_negates vector. */ + gimple feed = SSA_NAME_DEF_STMT (negate); + tree a = gimple_assign_rhs1 (feed); + tree rhs2 = gimple_assign_rhs2 (user); + gimple_stmt_iterator gsi = gsi_for_stmt (feed), gsi2; + gimple_replace_lhs (feed, negate); + gimple_assign_set_rhs_with_ops (&gsi, PLUS_EXPR, a, rhs2); + update_stmt (gsi_stmt (gsi)); + gsi2 = gsi_for_stmt (user); + gimple_assign_set_rhs_with_ops (&gsi2, NEGATE_EXPR, negate, NULL); + update_stmt (gsi_stmt (gsi2)); + gsi_move_before (&gsi, &gsi2); + VEC_safe_push (tree, heap, plus_negates, + gimple_assign_lhs (gsi_stmt (gsi2))); + } + else + { + /* Transform "x = -a; y = b - x" into "y = b + a", getting + rid of one operation. */ + gimple feed = SSA_NAME_DEF_STMT (negate); + tree a = gimple_assign_rhs1 (feed); + tree rhs1 = gimple_assign_rhs1 (user); + gimple_stmt_iterator gsi = gsi_for_stmt (user); + gimple_assign_set_rhs_with_ops (&gsi, PLUS_EXPR, rhs1, a); + update_stmt (gsi_stmt (gsi)); + } + } + } +} + +/* Returns true if OP is of a type for which we can do reassociation. + That is for integral or non-saturating fixed-point types, and for + floating point type when associative-math is enabled. */ + +static bool +can_reassociate_p (tree op) +{ + tree type = TREE_TYPE (op); + if ((INTEGRAL_TYPE_P (type) && TYPE_OVERFLOW_WRAPS (type)) + || NON_SAT_FIXED_POINT_TYPE_P (type) + || (flag_associative_math && FLOAT_TYPE_P (type))) + return true; + return false; +} + +/* Break up subtract operations in block BB. + + We do this top down because we don't know whether the subtract is + part of a possible chain of reassociation except at the top. + + IE given + d = f + g + c = a + e + b = c - d + q = b - r + k = t - q + + we want to break up k = t - q, but we won't until we've transformed q + = b - r, which won't be broken up until we transform b = c - d. + + En passant, clear the GIMPLE visited flag on every statement. */ + +static void +break_up_subtract_bb (basic_block bb) +{ + gimple_stmt_iterator gsi; + basic_block son; + + for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) + { + gimple stmt = gsi_stmt (gsi); + gimple_set_visited (stmt, false); + + if (!is_gimple_assign (stmt) + || !can_reassociate_p (gimple_assign_lhs (stmt))) + continue; + + /* Look for simple gimple subtract operations. */ + if (gimple_assign_rhs_code (stmt) == MINUS_EXPR) + { + if (!can_reassociate_p (gimple_assign_rhs1 (stmt)) + || !can_reassociate_p (gimple_assign_rhs2 (stmt))) + continue; + + /* Check for a subtract used only in an addition. If this + is the case, transform it into add of a negate for better + reassociation. IE transform C = A-B into C = A + -B if C + is only used in an addition. */ + if (should_break_up_subtract (stmt)) + break_up_subtract (stmt, &gsi); + } + else if (gimple_assign_rhs_code (stmt) == NEGATE_EXPR + && can_reassociate_p (gimple_assign_rhs1 (stmt))) + VEC_safe_push (tree, heap, plus_negates, gimple_assign_lhs (stmt)); + } + for (son = first_dom_son (CDI_DOMINATORS, bb); + son; + son = next_dom_son (CDI_DOMINATORS, son)) + break_up_subtract_bb (son); +} + +/* Reassociate expressions in basic block BB and its post-dominator as + children. */ + +static void +reassociate_bb (basic_block bb) +{ + gimple_stmt_iterator gsi; + basic_block son; + + for (gsi = gsi_last_bb (bb); !gsi_end_p (gsi); gsi_prev (&gsi)) + { + gimple stmt = gsi_stmt (gsi); + + if (is_gimple_assign (stmt) + && !stmt_could_throw_p (stmt)) + { + tree lhs, rhs1, rhs2; + enum tree_code rhs_code = gimple_assign_rhs_code (stmt); + + /* If this is not a gimple binary expression, there is + nothing for us to do with it. */ + if (get_gimple_rhs_class (rhs_code) != GIMPLE_BINARY_RHS) + continue; + + /* If this was part of an already processed statement, + we don't need to touch it again. */ + if (gimple_visited_p (stmt)) + { + /* This statement might have become dead because of previous + reassociations. */ + if (has_zero_uses (gimple_get_lhs (stmt))) + { + gsi_remove (&gsi, true); + release_defs (stmt); + /* We might end up removing the last stmt above which + places the iterator to the end of the sequence. + Reset it to the last stmt in this case which might + be the end of the sequence as well if we removed + the last statement of the sequence. In which case + we need to bail out. */ + if (gsi_end_p (gsi)) + { + gsi = gsi_last_bb (bb); + if (gsi_end_p (gsi)) + break; + } + } + continue; + } + + lhs = gimple_assign_lhs (stmt); + rhs1 = gimple_assign_rhs1 (stmt); + rhs2 = gimple_assign_rhs2 (stmt); + + /* For non-bit or min/max operations we can't associate + all types. Verify that here. */ + if (rhs_code != BIT_IOR_EXPR + && rhs_code != BIT_AND_EXPR + && rhs_code != BIT_XOR_EXPR + && rhs_code != MIN_EXPR + && rhs_code != MAX_EXPR + && (!can_reassociate_p (lhs) + || !can_reassociate_p (rhs1) + || !can_reassociate_p (rhs2))) + continue; + + if (associative_tree_code (rhs_code)) + { + VEC(operand_entry_t, heap) *ops = NULL; + + /* There may be no immediate uses left by the time we + get here because we may have eliminated them all. */ + if (TREE_CODE (lhs) == SSA_NAME && has_zero_uses (lhs)) + continue; + + gimple_set_visited (stmt, true); + linearize_expr_tree (&ops, stmt, true, true); + VEC_qsort (operand_entry_t, ops, sort_by_operand_rank); + optimize_ops_list (rhs_code, &ops); + if (undistribute_ops_list (rhs_code, &ops, + loop_containing_stmt (stmt))) + { + VEC_qsort (operand_entry_t, ops, sort_by_operand_rank); + optimize_ops_list (rhs_code, &ops); + } + + if (VEC_length (operand_entry_t, ops) == 1) + { + if (dump_file && (dump_flags & TDF_DETAILS)) + { + fprintf (dump_file, "Transforming "); + print_gimple_stmt (dump_file, stmt, 0, 0); + } + + rhs1 = gimple_assign_rhs1 (stmt); + gimple_assign_set_rhs_from_tree (&gsi, + VEC_last (operand_entry_t, + ops)->op); + update_stmt (stmt); + remove_visited_stmt_chain (rhs1); + + if (dump_file && (dump_flags & TDF_DETAILS)) + { + fprintf (dump_file, " into "); + print_gimple_stmt (dump_file, stmt, 0, 0); + } + } + else + rewrite_expr_tree (stmt, 0, ops, false); + + VEC_free (operand_entry_t, heap, ops); + } + } + } + for (son = first_dom_son (CDI_POST_DOMINATORS, bb); + son; + son = next_dom_son (CDI_POST_DOMINATORS, son)) + reassociate_bb (son); +} + +void dump_ops_vector (FILE *file, VEC (operand_entry_t, heap) *ops); +void debug_ops_vector (VEC (operand_entry_t, heap) *ops); + +/* Dump the operand entry vector OPS to FILE. */ + +void +dump_ops_vector (FILE *file, VEC (operand_entry_t, heap) *ops) +{ + operand_entry_t oe; + unsigned int i; + + FOR_EACH_VEC_ELT (operand_entry_t, ops, i, oe) + { + fprintf (file, "Op %d -> rank: %d, tree: ", i, oe->rank); + print_generic_expr (file, oe->op, 0); + } +} + +/* Dump the operand entry vector OPS to STDERR. */ + +DEBUG_FUNCTION void +debug_ops_vector (VEC (operand_entry_t, heap) *ops) +{ + dump_ops_vector (stderr, ops); +} + +static void +do_reassoc (void) +{ + break_up_subtract_bb (ENTRY_BLOCK_PTR); + reassociate_bb (EXIT_BLOCK_PTR); +} + +/* Initialize the reassociation pass. */ + +static void +init_reassoc (void) +{ + int i; + long rank = 2; + tree param; + int *bbs = XNEWVEC (int, last_basic_block + 1); + + /* Find the loops, so that we can prevent moving calculations in + them. */ + loop_optimizer_init (AVOID_CFG_MODIFICATIONS); + + memset (&reassociate_stats, 0, sizeof (reassociate_stats)); + + operand_entry_pool = create_alloc_pool ("operand entry pool", + sizeof (struct operand_entry), 30); + next_operand_entry_id = 0; + + /* Reverse RPO (Reverse Post Order) will give us something where + deeper loops come later. */ + pre_and_rev_post_order_compute (NULL, bbs, false); + bb_rank = XCNEWVEC (long, last_basic_block + 1); + operand_rank = pointer_map_create (); + + /* Give each argument a distinct rank. */ + for (param = DECL_ARGUMENTS (current_function_decl); + param; + param = DECL_CHAIN (param)) + { + if (gimple_default_def (cfun, param) != NULL) + { + tree def = gimple_default_def (cfun, param); + insert_operand_rank (def, ++rank); + } + } + + /* Give the chain decl a distinct rank. */ + if (cfun->static_chain_decl != NULL) + { + tree def = gimple_default_def (cfun, cfun->static_chain_decl); + if (def != NULL) + insert_operand_rank (def, ++rank); + } + + /* Set up rank for each BB */ + for (i = 0; i < n_basic_blocks - NUM_FIXED_BLOCKS; i++) + bb_rank[bbs[i]] = ++rank << 16; + + free (bbs); + calculate_dominance_info (CDI_POST_DOMINATORS); + plus_negates = NULL; +} + +/* Cleanup after the reassociation pass, and print stats if + requested. */ + +static void +fini_reassoc (void) +{ + statistics_counter_event (cfun, "Linearized", + reassociate_stats.linearized); + statistics_counter_event (cfun, "Constants eliminated", + reassociate_stats.constants_eliminated); + statistics_counter_event (cfun, "Ops eliminated", + reassociate_stats.ops_eliminated); + statistics_counter_event (cfun, "Statements rewritten", + reassociate_stats.rewritten); + + pointer_map_destroy (operand_rank); + free_alloc_pool (operand_entry_pool); + free (bb_rank); + VEC_free (tree, heap, plus_negates); + free_dominance_info (CDI_POST_DOMINATORS); + loop_optimizer_finalize (); +} + +/* Gate and execute functions for Reassociation. */ + +static unsigned int +execute_reassoc (void) +{ + init_reassoc (); + + do_reassoc (); + repropagate_negates (); + + fini_reassoc (); + return 0; +} + +static bool +gate_tree_ssa_reassoc (void) +{ + return flag_tree_reassoc != 0; +} + +struct gimple_opt_pass pass_reassoc = +{ + { + GIMPLE_PASS, + "reassoc", /* name */ + gate_tree_ssa_reassoc, /* gate */ + execute_reassoc, /* execute */ + NULL, /* sub */ + NULL, /* next */ + 0, /* static_pass_number */ + TV_TREE_REASSOC, /* tv_id */ + PROP_cfg | PROP_ssa, /* properties_required */ + 0, /* properties_provided */ + 0, /* properties_destroyed */ + 0, /* todo_flags_start */ + TODO_verify_ssa + | TODO_verify_flow + | TODO_dump_func + | TODO_ggc_collect /* todo_flags_finish */ + } +}; + -- cgit v1.2.3