| /* Header file for SSA dominator optimizations. |
| Copyright (C) 2013-2017 Free Software Foundation, Inc. |
| |
| This file is part of GCC. |
| |
| GCC is free software; you can redistribute it and/or modify it under |
| the terms of the GNU General Public License as published by the Free |
| Software Foundation; either version 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 |
| <http://www.gnu.org/licenses/>. */ |
| |
| #include "config.h" |
| #include "system.h" |
| #include "coretypes.h" |
| #include "function.h" |
| #include "basic-block.h" |
| #include "tree.h" |
| #include "gimple.h" |
| #include "tree-pass.h" |
| #include "tree-pretty-print.h" |
| #include "tree-ssa-scopedtables.h" |
| #include "tree-ssa-threadedge.h" |
| #include "stor-layout.h" |
| #include "fold-const.h" |
| #include "tree-eh.h" |
| #include "internal-fn.h" |
| #include "tree-dfa.h" |
| #include "options.h" |
| #include "params.h" |
| |
| static bool hashable_expr_equal_p (const struct hashable_expr *, |
| const struct hashable_expr *); |
| |
| /* Initialize local stacks for this optimizer and record equivalences |
| upon entry to BB. Equivalences can come from the edge traversed to |
| reach BB or they may come from PHI nodes at the start of BB. */ |
| |
| /* Pop items off the unwinding stack, removing each from the hash table |
| until a marker is encountered. */ |
| |
| void |
| avail_exprs_stack::pop_to_marker () |
| { |
| /* Remove all the expressions made available in this block. */ |
| while (m_stack.length () > 0) |
| { |
| std::pair<expr_hash_elt_t, expr_hash_elt_t> victim = m_stack.pop (); |
| expr_hash_elt **slot; |
| |
| if (victim.first == NULL) |
| break; |
| |
| /* This must precede the actual removal from the hash table, |
| as ELEMENT and the table entry may share a call argument |
| vector which will be freed during removal. */ |
| if (dump_file && (dump_flags & TDF_DETAILS)) |
| { |
| fprintf (dump_file, "<<<< "); |
| victim.first->print (dump_file); |
| } |
| |
| slot = m_avail_exprs->find_slot (victim.first, NO_INSERT); |
| gcc_assert (slot && *slot == victim.first); |
| if (victim.second != NULL) |
| { |
| delete *slot; |
| *slot = victim.second; |
| } |
| else |
| m_avail_exprs->clear_slot (slot); |
| } |
| } |
| |
| /* Add <ELT1,ELT2> to the unwinding stack so they can be later removed |
| from the hash table. */ |
| |
| void |
| avail_exprs_stack::record_expr (class expr_hash_elt *elt1, |
| class expr_hash_elt *elt2, |
| char type) |
| { |
| if (elt1 && dump_file && (dump_flags & TDF_DETAILS)) |
| { |
| fprintf (dump_file, "%c>>> ", type); |
| elt1->print (dump_file); |
| } |
| |
| m_stack.safe_push (std::pair<expr_hash_elt_t, expr_hash_elt_t> (elt1, elt2)); |
| } |
| |
| /* Helper for walk_non_aliased_vuses. Determine if we arrived at |
| the desired memory state. */ |
| |
| static void * |
| vuse_eq (ao_ref *, tree vuse1, unsigned int cnt, void *data) |
| { |
| tree vuse2 = (tree) data; |
| if (vuse1 == vuse2) |
| return data; |
| |
| /* This bounds the stmt walks we perform on reference lookups |
| to O(1) instead of O(N) where N is the number of dominating |
| stores leading to a candidate. We re-use the SCCVN param |
| for this as it is basically the same complexity. */ |
| if (cnt > (unsigned) PARAM_VALUE (PARAM_SCCVN_MAX_ALIAS_QUERIES_PER_ACCESS)) |
| return (void *)-1; |
| |
| return NULL; |
| } |
| |
| /* We looked for STMT in the hash table, but did not find it. |
| |
| If STMT is an assignment from a binary operator, we may know something |
| about the operands relationship to each other which would allow |
| us to derive a constant value for the RHS of STMT. */ |
| |
| tree |
| avail_exprs_stack::simplify_binary_operation (gimple *stmt, |
| class expr_hash_elt element) |
| { |
| if (is_gimple_assign (stmt)) |
| { |
| struct hashable_expr *expr = element.expr (); |
| if (expr->kind == EXPR_BINARY) |
| { |
| enum tree_code code = expr->ops.binary.op; |
| |
| switch (code) |
| { |
| /* For these cases, if we know the operands |
| are equal, then we know the result. */ |
| case MIN_EXPR: |
| case MAX_EXPR: |
| case BIT_IOR_EXPR: |
| case BIT_AND_EXPR: |
| case BIT_XOR_EXPR: |
| case MINUS_EXPR: |
| case TRUNC_DIV_EXPR: |
| case CEIL_DIV_EXPR: |
| case FLOOR_DIV_EXPR: |
| case ROUND_DIV_EXPR: |
| case EXACT_DIV_EXPR: |
| case TRUNC_MOD_EXPR: |
| case CEIL_MOD_EXPR: |
| case FLOOR_MOD_EXPR: |
| case ROUND_MOD_EXPR: |
| { |
| /* Build a simple equality expr and query the hash table |
| for it. */ |
| struct hashable_expr expr; |
| expr.type = boolean_type_node; |
| expr.kind = EXPR_BINARY; |
| expr.ops.binary.op = EQ_EXPR; |
| expr.ops.binary.opnd0 = gimple_assign_rhs1 (stmt); |
| expr.ops.binary.opnd1 = gimple_assign_rhs2 (stmt); |
| class expr_hash_elt element2 (&expr, NULL_TREE); |
| expr_hash_elt **slot |
| = m_avail_exprs->find_slot (&element2, NO_INSERT); |
| tree result_type = TREE_TYPE (gimple_assign_lhs (stmt)); |
| |
| /* If the query was successful and returned a nonzero |
| result, then we know that the operands of the binary |
| expression are the same. In many cases this allows |
| us to compute a constant result of the expression |
| at compile time, even if we do not know the exact |
| values of the operands. */ |
| if (slot && *slot && integer_onep ((*slot)->lhs ())) |
| { |
| switch (code) |
| { |
| case MIN_EXPR: |
| case MAX_EXPR: |
| case BIT_IOR_EXPR: |
| case BIT_AND_EXPR: |
| return gimple_assign_rhs1 (stmt); |
| |
| case BIT_XOR_EXPR: |
| case MINUS_EXPR: |
| case TRUNC_MOD_EXPR: |
| case CEIL_MOD_EXPR: |
| case FLOOR_MOD_EXPR: |
| case ROUND_MOD_EXPR: |
| return build_zero_cst (result_type); |
| |
| case TRUNC_DIV_EXPR: |
| case CEIL_DIV_EXPR: |
| case FLOOR_DIV_EXPR: |
| case ROUND_DIV_EXPR: |
| case EXACT_DIV_EXPR: |
| return build_one_cst (result_type); |
| |
| default: |
| gcc_unreachable (); |
| } |
| } |
| break; |
| } |
| |
| default: |
| break; |
| } |
| } |
| } |
| return NULL_TREE; |
| } |
| |
| /* Search for an existing instance of STMT in the AVAIL_EXPRS_STACK table. |
| If found, return its LHS. Otherwise insert STMT in the table and |
| return NULL_TREE. |
| |
| Also, when an expression is first inserted in the table, it is also |
| is also added to AVAIL_EXPRS_STACK, so that it can be removed when |
| we finish processing this block and its children. */ |
| |
| tree |
| avail_exprs_stack::lookup_avail_expr (gimple *stmt, bool insert, bool tbaa_p) |
| { |
| expr_hash_elt **slot; |
| tree lhs; |
| |
| /* Get LHS of phi, assignment, or call; else NULL_TREE. */ |
| if (gimple_code (stmt) == GIMPLE_PHI) |
| lhs = gimple_phi_result (stmt); |
| else |
| lhs = gimple_get_lhs (stmt); |
| |
| class expr_hash_elt element (stmt, lhs); |
| |
| if (dump_file && (dump_flags & TDF_DETAILS)) |
| { |
| fprintf (dump_file, "LKUP "); |
| element.print (dump_file); |
| } |
| |
| /* Don't bother remembering constant assignments and copy operations. |
| Constants and copy operations are handled by the constant/copy propagator |
| in optimize_stmt. */ |
| if (element.expr()->kind == EXPR_SINGLE |
| && (TREE_CODE (element.expr()->ops.single.rhs) == SSA_NAME |
| || is_gimple_min_invariant (element.expr()->ops.single.rhs))) |
| return NULL_TREE; |
| |
| /* Finally try to find the expression in the main expression hash table. */ |
| slot = m_avail_exprs->find_slot (&element, (insert ? INSERT : NO_INSERT)); |
| if (slot == NULL) |
| { |
| return NULL_TREE; |
| } |
| else if (*slot == NULL) |
| { |
| /* If we did not find the expression in the hash table, we may still |
| be able to produce a result for some expressions. */ |
| tree retval = avail_exprs_stack::simplify_binary_operation (stmt, |
| element); |
| |
| /* We have, in effect, allocated *SLOT for ELEMENT at this point. |
| We must initialize *SLOT to a real entry, even if we found a |
| way to prove ELEMENT was a constant after not finding ELEMENT |
| in the hash table. |
| |
| An uninitialized or empty slot is an indication no prior objects |
| entered into the hash table had a hash collection with ELEMENT. |
| |
| If we fail to do so and had such entries in the table, they |
| would become unreachable. */ |
| class expr_hash_elt *element2 = new expr_hash_elt (element); |
| *slot = element2; |
| |
| record_expr (element2, NULL, '2'); |
| return retval; |
| } |
| |
| /* If we found a redundant memory operation do an alias walk to |
| check if we can re-use it. */ |
| if (gimple_vuse (stmt) != (*slot)->vop ()) |
| { |
| tree vuse1 = (*slot)->vop (); |
| tree vuse2 = gimple_vuse (stmt); |
| /* If we have a load of a register and a candidate in the |
| hash with vuse1 then try to reach its stmt by walking |
| up the virtual use-def chain using walk_non_aliased_vuses. |
| But don't do this when removing expressions from the hash. */ |
| ao_ref ref; |
| if (!(vuse1 && vuse2 |
| && gimple_assign_single_p (stmt) |
| && TREE_CODE (gimple_assign_lhs (stmt)) == SSA_NAME |
| && (ao_ref_init (&ref, gimple_assign_rhs1 (stmt)), |
| ref.base_alias_set = ref.ref_alias_set = tbaa_p ? -1 : 0, true) |
| && walk_non_aliased_vuses (&ref, vuse2, |
| vuse_eq, NULL, NULL, vuse1) != NULL)) |
| { |
| if (insert) |
| { |
| class expr_hash_elt *element2 = new expr_hash_elt (element); |
| |
| /* Insert the expr into the hash by replacing the current |
| entry and recording the value to restore in the |
| avail_exprs_stack. */ |
| record_expr (element2, *slot, '2'); |
| *slot = element2; |
| } |
| return NULL_TREE; |
| } |
| } |
| |
| /* Extract the LHS of the assignment so that it can be used as the current |
| definition of another variable. */ |
| lhs = (*slot)->lhs (); |
| |
| /* Valueize the result. */ |
| if (TREE_CODE (lhs) == SSA_NAME) |
| { |
| tree tem = SSA_NAME_VALUE (lhs); |
| if (tem) |
| lhs = tem; |
| } |
| |
| if (dump_file && (dump_flags & TDF_DETAILS)) |
| { |
| fprintf (dump_file, "FIND: "); |
| print_generic_expr (dump_file, lhs); |
| fprintf (dump_file, "\n"); |
| } |
| |
| return lhs; |
| } |
| |
| /* Enter condition equivalence P into the hash table. |
| |
| This indicates that a conditional expression has a known |
| boolean value. */ |
| |
| void |
| avail_exprs_stack::record_cond (cond_equivalence *p) |
| { |
| class expr_hash_elt *element = new expr_hash_elt (&p->cond, p->value); |
| expr_hash_elt **slot; |
| |
| slot = m_avail_exprs->find_slot_with_hash (element, element->hash (), INSERT); |
| if (*slot == NULL) |
| { |
| *slot = element; |
| record_expr (element, NULL, '1'); |
| } |
| else |
| delete element; |
| } |
| |
| /* Generate a hash value for a pair of expressions. This can be used |
| iteratively by passing a previous result in HSTATE. |
| |
| The same hash value is always returned for a given pair of expressions, |
| regardless of the order in which they are presented. This is useful in |
| hashing the operands of commutative functions. */ |
| |
| namespace inchash |
| { |
| |
| static void |
| add_expr_commutative (const_tree t1, const_tree t2, hash &hstate) |
| { |
| hash one, two; |
| |
| inchash::add_expr (t1, one); |
| inchash::add_expr (t2, two); |
| hstate.add_commutative (one, two); |
| } |
| |
| /* Compute a hash value for a hashable_expr value EXPR and a |
| previously accumulated hash value VAL. If two hashable_expr |
| values compare equal with hashable_expr_equal_p, they must |
| hash to the same value, given an identical value of VAL. |
| The logic is intended to follow inchash::add_expr in tree.c. */ |
| |
| static void |
| add_hashable_expr (const struct hashable_expr *expr, hash &hstate) |
| { |
| switch (expr->kind) |
| { |
| case EXPR_SINGLE: |
| inchash::add_expr (expr->ops.single.rhs, hstate); |
| break; |
| |
| case EXPR_UNARY: |
| hstate.add_object (expr->ops.unary.op); |
| |
| /* Make sure to include signedness in the hash computation. |
| Don't hash the type, that can lead to having nodes which |
| compare equal according to operand_equal_p, but which |
| have different hash codes. */ |
| if (CONVERT_EXPR_CODE_P (expr->ops.unary.op) |
| || expr->ops.unary.op == NON_LVALUE_EXPR) |
| hstate.add_int (TYPE_UNSIGNED (expr->type)); |
| |
| inchash::add_expr (expr->ops.unary.opnd, hstate); |
| break; |
| |
| case EXPR_BINARY: |
| hstate.add_object (expr->ops.binary.op); |
| if (commutative_tree_code (expr->ops.binary.op)) |
| inchash::add_expr_commutative (expr->ops.binary.opnd0, |
| expr->ops.binary.opnd1, hstate); |
| else |
| { |
| inchash::add_expr (expr->ops.binary.opnd0, hstate); |
| inchash::add_expr (expr->ops.binary.opnd1, hstate); |
| } |
| break; |
| |
| case EXPR_TERNARY: |
| hstate.add_object (expr->ops.ternary.op); |
| if (commutative_ternary_tree_code (expr->ops.ternary.op)) |
| inchash::add_expr_commutative (expr->ops.ternary.opnd0, |
| expr->ops.ternary.opnd1, hstate); |
| else |
| { |
| inchash::add_expr (expr->ops.ternary.opnd0, hstate); |
| inchash::add_expr (expr->ops.ternary.opnd1, hstate); |
| } |
| inchash::add_expr (expr->ops.ternary.opnd2, hstate); |
| break; |
| |
| case EXPR_CALL: |
| { |
| size_t i; |
| enum tree_code code = CALL_EXPR; |
| gcall *fn_from; |
| |
| hstate.add_object (code); |
| fn_from = expr->ops.call.fn_from; |
| if (gimple_call_internal_p (fn_from)) |
| hstate.merge_hash ((hashval_t) gimple_call_internal_fn (fn_from)); |
| else |
| inchash::add_expr (gimple_call_fn (fn_from), hstate); |
| for (i = 0; i < expr->ops.call.nargs; i++) |
| inchash::add_expr (expr->ops.call.args[i], hstate); |
| } |
| break; |
| |
| case EXPR_PHI: |
| { |
| size_t i; |
| |
| for (i = 0; i < expr->ops.phi.nargs; i++) |
| inchash::add_expr (expr->ops.phi.args[i], hstate); |
| } |
| break; |
| |
| default: |
| gcc_unreachable (); |
| } |
| } |
| |
| } |
| |
| /* Hashing and equality functions. We compute a value number for expressions |
| using the code of the expression and the SSA numbers of its operands. */ |
| |
| static hashval_t |
| avail_expr_hash (class expr_hash_elt *p) |
| { |
| const struct hashable_expr *expr = p->expr (); |
| inchash::hash hstate; |
| |
| if (expr->kind == EXPR_SINGLE) |
| { |
| /* T could potentially be a switch index or a goto dest. */ |
| tree t = expr->ops.single.rhs; |
| if (TREE_CODE (t) == MEM_REF || handled_component_p (t)) |
| { |
| /* Make equivalent statements of both these kinds hash together. |
| Dealing with both MEM_REF and ARRAY_REF allows us not to care |
| about equivalence with other statements not considered here. */ |
| bool reverse; |
| HOST_WIDE_INT offset, size, max_size; |
| tree base = get_ref_base_and_extent (t, &offset, &size, &max_size, |
| &reverse); |
| /* Strictly, we could try to normalize variable-sized accesses too, |
| but here we just deal with the common case. */ |
| if (size != -1 |
| && size == max_size) |
| { |
| enum tree_code code = MEM_REF; |
| hstate.add_object (code); |
| inchash::add_expr (base, hstate); |
| hstate.add_object (offset); |
| hstate.add_object (size); |
| return hstate.end (); |
| } |
| } |
| } |
| |
| inchash::add_hashable_expr (expr, hstate); |
| |
| return hstate.end (); |
| } |
| |
| /* Compares trees T0 and T1 to see if they are MEM_REF or ARRAY_REFs equivalent |
| to each other. (That is, they return the value of the same bit of memory.) |
| |
| Return TRUE if the two are so equivalent; FALSE if not (which could still |
| mean the two are equivalent by other means). */ |
| |
| static bool |
| equal_mem_array_ref_p (tree t0, tree t1) |
| { |
| if (TREE_CODE (t0) != MEM_REF && ! handled_component_p (t0)) |
| return false; |
| if (TREE_CODE (t1) != MEM_REF && ! handled_component_p (t1)) |
| return false; |
| |
| if (!types_compatible_p (TREE_TYPE (t0), TREE_TYPE (t1))) |
| return false; |
| bool rev0; |
| HOST_WIDE_INT off0, sz0, max0; |
| tree base0 = get_ref_base_and_extent (t0, &off0, &sz0, &max0, &rev0); |
| if (sz0 == -1 |
| || sz0 != max0) |
| return false; |
| |
| bool rev1; |
| HOST_WIDE_INT off1, sz1, max1; |
| tree base1 = get_ref_base_and_extent (t1, &off1, &sz1, &max1, &rev1); |
| if (sz1 == -1 |
| || sz1 != max1) |
| return false; |
| |
| if (rev0 != rev1) |
| return false; |
| |
| /* Types were compatible, so this is a sanity check. */ |
| gcc_assert (sz0 == sz1); |
| |
| return (off0 == off1) && operand_equal_p (base0, base1, 0); |
| } |
| |
| /* Compare two hashable_expr structures for equivalence. They are |
| considered equivalent when the expressions they denote must |
| necessarily be equal. The logic is intended to follow that of |
| operand_equal_p in fold-const.c */ |
| |
| static bool |
| hashable_expr_equal_p (const struct hashable_expr *expr0, |
| const struct hashable_expr *expr1) |
| { |
| tree type0 = expr0->type; |
| tree type1 = expr1->type; |
| |
| /* If either type is NULL, there is nothing to check. */ |
| if ((type0 == NULL_TREE) ^ (type1 == NULL_TREE)) |
| return false; |
| |
| /* If both types don't have the same signedness, precision, and mode, |
| then we can't consider them equal. */ |
| if (type0 != type1 |
| && (TREE_CODE (type0) == ERROR_MARK |
| || TREE_CODE (type1) == ERROR_MARK |
| || TYPE_UNSIGNED (type0) != TYPE_UNSIGNED (type1) |
| || TYPE_PRECISION (type0) != TYPE_PRECISION (type1) |
| || TYPE_MODE (type0) != TYPE_MODE (type1))) |
| return false; |
| |
| if (expr0->kind != expr1->kind) |
| return false; |
| |
| switch (expr0->kind) |
| { |
| case EXPR_SINGLE: |
| return equal_mem_array_ref_p (expr0->ops.single.rhs, |
| expr1->ops.single.rhs) |
| || operand_equal_p (expr0->ops.single.rhs, |
| expr1->ops.single.rhs, 0); |
| case EXPR_UNARY: |
| if (expr0->ops.unary.op != expr1->ops.unary.op) |
| return false; |
| |
| if ((CONVERT_EXPR_CODE_P (expr0->ops.unary.op) |
| || expr0->ops.unary.op == NON_LVALUE_EXPR) |
| && TYPE_UNSIGNED (expr0->type) != TYPE_UNSIGNED (expr1->type)) |
| return false; |
| |
| return operand_equal_p (expr0->ops.unary.opnd, |
| expr1->ops.unary.opnd, 0); |
| |
| case EXPR_BINARY: |
| if (expr0->ops.binary.op != expr1->ops.binary.op) |
| return false; |
| |
| if (operand_equal_p (expr0->ops.binary.opnd0, |
| expr1->ops.binary.opnd0, 0) |
| && operand_equal_p (expr0->ops.binary.opnd1, |
| expr1->ops.binary.opnd1, 0)) |
| return true; |
| |
| /* For commutative ops, allow the other order. */ |
| return (commutative_tree_code (expr0->ops.binary.op) |
| && operand_equal_p (expr0->ops.binary.opnd0, |
| expr1->ops.binary.opnd1, 0) |
| && operand_equal_p (expr0->ops.binary.opnd1, |
| expr1->ops.binary.opnd0, 0)); |
| |
| case EXPR_TERNARY: |
| if (expr0->ops.ternary.op != expr1->ops.ternary.op |
| || !operand_equal_p (expr0->ops.ternary.opnd2, |
| expr1->ops.ternary.opnd2, 0)) |
| return false; |
| |
| /* BIT_INSERT_EXPR has an implict operand as the type precision |
| of op1. Need to check to make sure they are the same. */ |
| if (expr0->ops.ternary.op == BIT_INSERT_EXPR |
| && TREE_CODE (expr0->ops.ternary.opnd1) == INTEGER_CST |
| && TREE_CODE (expr1->ops.ternary.opnd1) == INTEGER_CST |
| && TYPE_PRECISION (TREE_TYPE (expr0->ops.ternary.opnd1)) |
| != TYPE_PRECISION (TREE_TYPE (expr1->ops.ternary.opnd1))) |
| return false; |
| |
| if (operand_equal_p (expr0->ops.ternary.opnd0, |
| expr1->ops.ternary.opnd0, 0) |
| && operand_equal_p (expr0->ops.ternary.opnd1, |
| expr1->ops.ternary.opnd1, 0)) |
| return true; |
| |
| /* For commutative ops, allow the other order. */ |
| return (commutative_ternary_tree_code (expr0->ops.ternary.op) |
| && operand_equal_p (expr0->ops.ternary.opnd0, |
| expr1->ops.ternary.opnd1, 0) |
| && operand_equal_p (expr0->ops.ternary.opnd1, |
| expr1->ops.ternary.opnd0, 0)); |
| |
| case EXPR_CALL: |
| { |
| size_t i; |
| |
| /* If the calls are to different functions, then they |
| clearly cannot be equal. */ |
| if (!gimple_call_same_target_p (expr0->ops.call.fn_from, |
| expr1->ops.call.fn_from)) |
| return false; |
| |
| if (! expr0->ops.call.pure) |
| return false; |
| |
| if (expr0->ops.call.nargs != expr1->ops.call.nargs) |
| return false; |
| |
| for (i = 0; i < expr0->ops.call.nargs; i++) |
| if (! operand_equal_p (expr0->ops.call.args[i], |
| expr1->ops.call.args[i], 0)) |
| return false; |
| |
| if (stmt_could_throw_p (expr0->ops.call.fn_from)) |
| { |
| int lp0 = lookup_stmt_eh_lp (expr0->ops.call.fn_from); |
| int lp1 = lookup_stmt_eh_lp (expr1->ops.call.fn_from); |
| if ((lp0 > 0 || lp1 > 0) && lp0 != lp1) |
| return false; |
| } |
| |
| return true; |
| } |
| |
| case EXPR_PHI: |
| { |
| size_t i; |
| |
| if (expr0->ops.phi.nargs != expr1->ops.phi.nargs) |
| return false; |
| |
| for (i = 0; i < expr0->ops.phi.nargs; i++) |
| if (! operand_equal_p (expr0->ops.phi.args[i], |
| expr1->ops.phi.args[i], 0)) |
| return false; |
| |
| return true; |
| } |
| |
| default: |
| gcc_unreachable (); |
| } |
| } |
| |
| /* Given a statement STMT, construct a hash table element. */ |
| |
| expr_hash_elt::expr_hash_elt (gimple *stmt, tree orig_lhs) |
| { |
| enum gimple_code code = gimple_code (stmt); |
| struct hashable_expr *expr = this->expr (); |
| |
| if (code == GIMPLE_ASSIGN) |
| { |
| enum tree_code subcode = gimple_assign_rhs_code (stmt); |
| |
| switch (get_gimple_rhs_class (subcode)) |
| { |
| case GIMPLE_SINGLE_RHS: |
| expr->kind = EXPR_SINGLE; |
| expr->type = TREE_TYPE (gimple_assign_rhs1 (stmt)); |
| expr->ops.single.rhs = gimple_assign_rhs1 (stmt); |
| break; |
| case GIMPLE_UNARY_RHS: |
| expr->kind = EXPR_UNARY; |
| expr->type = TREE_TYPE (gimple_assign_lhs (stmt)); |
| if (CONVERT_EXPR_CODE_P (subcode)) |
| subcode = NOP_EXPR; |
| expr->ops.unary.op = subcode; |
| expr->ops.unary.opnd = gimple_assign_rhs1 (stmt); |
| break; |
| case GIMPLE_BINARY_RHS: |
| expr->kind = EXPR_BINARY; |
| expr->type = TREE_TYPE (gimple_assign_lhs (stmt)); |
| expr->ops.binary.op = subcode; |
| expr->ops.binary.opnd0 = gimple_assign_rhs1 (stmt); |
| expr->ops.binary.opnd1 = gimple_assign_rhs2 (stmt); |
| break; |
| case GIMPLE_TERNARY_RHS: |
| expr->kind = EXPR_TERNARY; |
| expr->type = TREE_TYPE (gimple_assign_lhs (stmt)); |
| expr->ops.ternary.op = subcode; |
| expr->ops.ternary.opnd0 = gimple_assign_rhs1 (stmt); |
| expr->ops.ternary.opnd1 = gimple_assign_rhs2 (stmt); |
| expr->ops.ternary.opnd2 = gimple_assign_rhs3 (stmt); |
| break; |
| default: |
| gcc_unreachable (); |
| } |
| } |
| else if (code == GIMPLE_COND) |
| { |
| expr->type = boolean_type_node; |
| expr->kind = EXPR_BINARY; |
| expr->ops.binary.op = gimple_cond_code (stmt); |
| expr->ops.binary.opnd0 = gimple_cond_lhs (stmt); |
| expr->ops.binary.opnd1 = gimple_cond_rhs (stmt); |
| } |
| else if (gcall *call_stmt = dyn_cast <gcall *> (stmt)) |
| { |
| size_t nargs = gimple_call_num_args (call_stmt); |
| size_t i; |
| |
| gcc_assert (gimple_call_lhs (call_stmt)); |
| |
| expr->type = TREE_TYPE (gimple_call_lhs (call_stmt)); |
| expr->kind = EXPR_CALL; |
| expr->ops.call.fn_from = call_stmt; |
| |
| if (gimple_call_flags (call_stmt) & (ECF_CONST | ECF_PURE)) |
| expr->ops.call.pure = true; |
| else |
| expr->ops.call.pure = false; |
| |
| expr->ops.call.nargs = nargs; |
| expr->ops.call.args = XCNEWVEC (tree, nargs); |
| for (i = 0; i < nargs; i++) |
| expr->ops.call.args[i] = gimple_call_arg (call_stmt, i); |
| } |
| else if (gswitch *swtch_stmt = dyn_cast <gswitch *> (stmt)) |
| { |
| expr->type = TREE_TYPE (gimple_switch_index (swtch_stmt)); |
| expr->kind = EXPR_SINGLE; |
| expr->ops.single.rhs = gimple_switch_index (swtch_stmt); |
| } |
| else if (code == GIMPLE_GOTO) |
| { |
| expr->type = TREE_TYPE (gimple_goto_dest (stmt)); |
| expr->kind = EXPR_SINGLE; |
| expr->ops.single.rhs = gimple_goto_dest (stmt); |
| } |
| else if (code == GIMPLE_PHI) |
| { |
| size_t nargs = gimple_phi_num_args (stmt); |
| size_t i; |
| |
| expr->type = TREE_TYPE (gimple_phi_result (stmt)); |
| expr->kind = EXPR_PHI; |
| expr->ops.phi.nargs = nargs; |
| expr->ops.phi.args = XCNEWVEC (tree, nargs); |
| for (i = 0; i < nargs; i++) |
| expr->ops.phi.args[i] = gimple_phi_arg_def (stmt, i); |
| } |
| else |
| gcc_unreachable (); |
| |
| m_lhs = orig_lhs; |
| m_vop = gimple_vuse (stmt); |
| m_hash = avail_expr_hash (this); |
| m_stamp = this; |
| } |
| |
| /* Given a hashable_expr expression ORIG and an ORIG_LHS, |
| construct a hash table element. */ |
| |
| expr_hash_elt::expr_hash_elt (struct hashable_expr *orig, tree orig_lhs) |
| { |
| m_expr = *orig; |
| m_lhs = orig_lhs; |
| m_vop = NULL_TREE; |
| m_hash = avail_expr_hash (this); |
| m_stamp = this; |
| } |
| |
| /* Copy constructor for a hash table element. */ |
| |
| expr_hash_elt::expr_hash_elt (class expr_hash_elt &old_elt) |
| { |
| m_expr = old_elt.m_expr; |
| m_lhs = old_elt.m_lhs; |
| m_vop = old_elt.m_vop; |
| m_hash = old_elt.m_hash; |
| m_stamp = this; |
| |
| /* Now deep copy the malloc'd space for CALL and PHI args. */ |
| if (old_elt.m_expr.kind == EXPR_CALL) |
| { |
| size_t nargs = old_elt.m_expr.ops.call.nargs; |
| size_t i; |
| |
| m_expr.ops.call.args = XCNEWVEC (tree, nargs); |
| for (i = 0; i < nargs; i++) |
| m_expr.ops.call.args[i] = old_elt.m_expr.ops.call.args[i]; |
| } |
| else if (old_elt.m_expr.kind == EXPR_PHI) |
| { |
| size_t nargs = old_elt.m_expr.ops.phi.nargs; |
| size_t i; |
| |
| m_expr.ops.phi.args = XCNEWVEC (tree, nargs); |
| for (i = 0; i < nargs; i++) |
| m_expr.ops.phi.args[i] = old_elt.m_expr.ops.phi.args[i]; |
| } |
| } |
| |
| /* Calls and PHIs have a variable number of arguments that are allocated |
| on the heap. Thus we have to have a special dtor to release them. */ |
| |
| expr_hash_elt::~expr_hash_elt () |
| { |
| if (m_expr.kind == EXPR_CALL) |
| free (m_expr.ops.call.args); |
| else if (m_expr.kind == EXPR_PHI) |
| free (m_expr.ops.phi.args); |
| } |
| |
| /* Print a diagnostic dump of an expression hash table entry. */ |
| |
| void |
| expr_hash_elt::print (FILE *stream) |
| { |
| fprintf (stream, "STMT "); |
| |
| if (m_lhs) |
| { |
| print_generic_expr (stream, m_lhs); |
| fprintf (stream, " = "); |
| } |
| |
| switch (m_expr.kind) |
| { |
| case EXPR_SINGLE: |
| print_generic_expr (stream, m_expr.ops.single.rhs); |
| break; |
| |
| case EXPR_UNARY: |
| fprintf (stream, "%s ", get_tree_code_name (m_expr.ops.unary.op)); |
| print_generic_expr (stream, m_expr.ops.unary.opnd); |
| break; |
| |
| case EXPR_BINARY: |
| print_generic_expr (stream, m_expr.ops.binary.opnd0); |
| fprintf (stream, " %s ", get_tree_code_name (m_expr.ops.binary.op)); |
| print_generic_expr (stream, m_expr.ops.binary.opnd1); |
| break; |
| |
| case EXPR_TERNARY: |
| fprintf (stream, " %s <", get_tree_code_name (m_expr.ops.ternary.op)); |
| print_generic_expr (stream, m_expr.ops.ternary.opnd0); |
| fputs (", ", stream); |
| print_generic_expr (stream, m_expr.ops.ternary.opnd1); |
| fputs (", ", stream); |
| print_generic_expr (stream, m_expr.ops.ternary.opnd2); |
| fputs (">", stream); |
| break; |
| |
| case EXPR_CALL: |
| { |
| size_t i; |
| size_t nargs = m_expr.ops.call.nargs; |
| gcall *fn_from; |
| |
| fn_from = m_expr.ops.call.fn_from; |
| if (gimple_call_internal_p (fn_from)) |
| fputs (internal_fn_name (gimple_call_internal_fn (fn_from)), |
| stream); |
| else |
| print_generic_expr (stream, gimple_call_fn (fn_from)); |
| fprintf (stream, " ("); |
| for (i = 0; i < nargs; i++) |
| { |
| print_generic_expr (stream, m_expr.ops.call.args[i]); |
| if (i + 1 < nargs) |
| fprintf (stream, ", "); |
| } |
| fprintf (stream, ")"); |
| } |
| break; |
| |
| case EXPR_PHI: |
| { |
| size_t i; |
| size_t nargs = m_expr.ops.phi.nargs; |
| |
| fprintf (stream, "PHI <"); |
| for (i = 0; i < nargs; i++) |
| { |
| print_generic_expr (stream, m_expr.ops.phi.args[i]); |
| if (i + 1 < nargs) |
| fprintf (stream, ", "); |
| } |
| fprintf (stream, ">"); |
| } |
| break; |
| } |
| |
| if (m_vop) |
| { |
| fprintf (stream, " with "); |
| print_generic_expr (stream, m_vop); |
| } |
| |
| fprintf (stream, "\n"); |
| } |
| |
| /* Pop entries off the stack until we hit the NULL marker. |
| For each entry popped, use the SRC/DEST pair to restore |
| SRC to its prior value. */ |
| |
| void |
| const_and_copies::pop_to_marker (void) |
| { |
| while (m_stack.length () > 0) |
| { |
| tree prev_value, dest; |
| |
| dest = m_stack.pop (); |
| |
| /* A NULL value indicates we should stop unwinding, otherwise |
| pop off the next entry as they're recorded in pairs. */ |
| if (dest == NULL) |
| break; |
| |
| if (dump_file && (dump_flags & TDF_DETAILS)) |
| { |
| fprintf (dump_file, "<<<< COPY "); |
| print_generic_expr (dump_file, dest); |
| fprintf (dump_file, " = "); |
| print_generic_expr (dump_file, SSA_NAME_VALUE (dest)); |
| fprintf (dump_file, "\n"); |
| } |
| |
| prev_value = m_stack.pop (); |
| set_ssa_name_value (dest, prev_value); |
| } |
| } |
| |
| /* Record that X has the value Y and that X's previous value is PREV_X. |
| |
| This variant does not follow the value chain for Y. */ |
| |
| void |
| const_and_copies::record_const_or_copy_raw (tree x, tree y, tree prev_x) |
| { |
| if (dump_file && (dump_flags & TDF_DETAILS)) |
| { |
| fprintf (dump_file, "0>>> COPY "); |
| print_generic_expr (dump_file, x); |
| fprintf (dump_file, " = "); |
| print_generic_expr (dump_file, y); |
| fprintf (dump_file, "\n"); |
| } |
| |
| set_ssa_name_value (x, y); |
| m_stack.reserve (2); |
| m_stack.quick_push (prev_x); |
| m_stack.quick_push (x); |
| } |
| |
| /* Record that X has the value Y. */ |
| |
| void |
| const_and_copies::record_const_or_copy (tree x, tree y) |
| { |
| record_const_or_copy (x, y, SSA_NAME_VALUE (x)); |
| } |
| |
| /* Record that X has the value Y and that X's previous value is PREV_X. |
| |
| This variant follow's Y value chain. */ |
| |
| void |
| const_and_copies::record_const_or_copy (tree x, tree y, tree prev_x) |
| { |
| /* Y may be NULL if we are invalidating entries in the table. */ |
| if (y && TREE_CODE (y) == SSA_NAME) |
| { |
| tree tmp = SSA_NAME_VALUE (y); |
| y = tmp ? tmp : y; |
| } |
| |
| record_const_or_copy_raw (x, y, prev_x); |
| } |
| |
| bool |
| expr_elt_hasher::equal (const value_type &p1, const compare_type &p2) |
| { |
| const struct hashable_expr *expr1 = p1->expr (); |
| const struct expr_hash_elt *stamp1 = p1->stamp (); |
| const struct hashable_expr *expr2 = p2->expr (); |
| const struct expr_hash_elt *stamp2 = p2->stamp (); |
| |
| /* This case should apply only when removing entries from the table. */ |
| if (stamp1 == stamp2) |
| return true; |
| |
| if (p1->hash () != p2->hash ()) |
| return false; |
| |
| /* In case of a collision, both RHS have to be identical and have the |
| same VUSE operands. */ |
| if (hashable_expr_equal_p (expr1, expr2) |
| && types_compatible_p (expr1->type, expr2->type)) |
| return true; |
| |
| return false; |
| } |
| |
| /* Given a conditional expression COND as a tree, initialize |
| a hashable_expr expression EXPR. The conditional must be a |
| comparison or logical negation. A constant or a variable is |
| not permitted. */ |
| |
| void |
| initialize_expr_from_cond (tree cond, struct hashable_expr *expr) |
| { |
| expr->type = boolean_type_node; |
| |
| if (COMPARISON_CLASS_P (cond)) |
| { |
| expr->kind = EXPR_BINARY; |
| expr->ops.binary.op = TREE_CODE (cond); |
| expr->ops.binary.opnd0 = TREE_OPERAND (cond, 0); |
| expr->ops.binary.opnd1 = TREE_OPERAND (cond, 1); |
| } |
| else if (TREE_CODE (cond) == TRUTH_NOT_EXPR) |
| { |
| expr->kind = EXPR_UNARY; |
| expr->ops.unary.op = TRUTH_NOT_EXPR; |
| expr->ops.unary.opnd = TREE_OPERAND (cond, 0); |
| } |
| else |
| gcc_unreachable (); |
| } |
| |
| /* Build a cond_equivalence record indicating that the comparison |
| CODE holds between operands OP0 and OP1 and push it to **P. */ |
| |
| static void |
| build_and_record_new_cond (enum tree_code code, |
| tree op0, tree op1, |
| vec<cond_equivalence> *p, |
| bool val = true) |
| { |
| cond_equivalence c; |
| struct hashable_expr *cond = &c.cond; |
| |
| gcc_assert (TREE_CODE_CLASS (code) == tcc_comparison); |
| |
| cond->type = boolean_type_node; |
| cond->kind = EXPR_BINARY; |
| cond->ops.binary.op = code; |
| cond->ops.binary.opnd0 = op0; |
| cond->ops.binary.opnd1 = op1; |
| |
| c.value = val ? boolean_true_node : boolean_false_node; |
| p->safe_push (c); |
| } |
| |
| /* Record that COND is true and INVERTED is false into the edge information |
| structure. Also record that any conditions dominated by COND are true |
| as well. |
| |
| For example, if a < b is true, then a <= b must also be true. */ |
| |
| void |
| record_conditions (vec<cond_equivalence> *p, tree cond, tree inverted) |
| { |
| tree op0, op1; |
| cond_equivalence c; |
| |
| if (!COMPARISON_CLASS_P (cond)) |
| return; |
| |
| op0 = TREE_OPERAND (cond, 0); |
| op1 = TREE_OPERAND (cond, 1); |
| |
| switch (TREE_CODE (cond)) |
| { |
| case LT_EXPR: |
| case GT_EXPR: |
| if (FLOAT_TYPE_P (TREE_TYPE (op0))) |
| { |
| build_and_record_new_cond (ORDERED_EXPR, op0, op1, p); |
| build_and_record_new_cond (LTGT_EXPR, op0, op1, p); |
| } |
| |
| build_and_record_new_cond ((TREE_CODE (cond) == LT_EXPR |
| ? LE_EXPR : GE_EXPR), |
| op0, op1, p); |
| build_and_record_new_cond (NE_EXPR, op0, op1, p); |
| build_and_record_new_cond (EQ_EXPR, op0, op1, p, false); |
| break; |
| |
| case GE_EXPR: |
| case LE_EXPR: |
| if (FLOAT_TYPE_P (TREE_TYPE (op0))) |
| { |
| build_and_record_new_cond (ORDERED_EXPR, op0, op1, p); |
| } |
| break; |
| |
| case EQ_EXPR: |
| if (FLOAT_TYPE_P (TREE_TYPE (op0))) |
| { |
| build_and_record_new_cond (ORDERED_EXPR, op0, op1, p); |
| } |
| build_and_record_new_cond (LE_EXPR, op0, op1, p); |
| build_and_record_new_cond (GE_EXPR, op0, op1, p); |
| break; |
| |
| case UNORDERED_EXPR: |
| build_and_record_new_cond (NE_EXPR, op0, op1, p); |
| build_and_record_new_cond (UNLE_EXPR, op0, op1, p); |
| build_and_record_new_cond (UNGE_EXPR, op0, op1, p); |
| build_and_record_new_cond (UNEQ_EXPR, op0, op1, p); |
| build_and_record_new_cond (UNLT_EXPR, op0, op1, p); |
| build_and_record_new_cond (UNGT_EXPR, op0, op1, p); |
| break; |
| |
| case UNLT_EXPR: |
| case UNGT_EXPR: |
| build_and_record_new_cond ((TREE_CODE (cond) == UNLT_EXPR |
| ? UNLE_EXPR : UNGE_EXPR), |
| op0, op1, p); |
| build_and_record_new_cond (NE_EXPR, op0, op1, p); |
| break; |
| |
| case UNEQ_EXPR: |
| build_and_record_new_cond (UNLE_EXPR, op0, op1, p); |
| build_and_record_new_cond (UNGE_EXPR, op0, op1, p); |
| break; |
| |
| case LTGT_EXPR: |
| build_and_record_new_cond (NE_EXPR, op0, op1, p); |
| build_and_record_new_cond (ORDERED_EXPR, op0, op1, p); |
| break; |
| |
| default: |
| break; |
| } |
| |
| /* Now store the original true and false conditions into the first |
| two slots. */ |
| initialize_expr_from_cond (cond, &c.cond); |
| c.value = boolean_true_node; |
| p->safe_push (c); |
| |
| /* It is possible for INVERTED to be the negation of a comparison, |
| and not a valid RHS or GIMPLE_COND condition. This happens because |
| invert_truthvalue may return such an expression when asked to invert |
| a floating-point comparison. These comparisons are not assumed to |
| obey the trichotomy law. */ |
| initialize_expr_from_cond (inverted, &c.cond); |
| c.value = boolean_false_node; |
| p->safe_push (c); |
| } |