-/* Copyright (C) 1998 - 2000 by Universitaet Karlsruhe
-** All rights reserved.
-**
-** Authors: Martin Trapp, Christian Schaefer
-**
-** irgmod: ir graph modification
-*/
-
-# include "irgmod.h"
-# include "iropt.h"
-
-/* ir_node * */
-/* arg_access (ir_mode *mode, long proj) */
-/* { */
-/* return new_r_Proj (current_ir_graph, current_ir_graph->start, */
-/* current_ir_graph->args, mode, proj); */
-/* } */
-
-
-/* these two functions are used in phi_merge, but defined in ircons.c */
-inline ir_node * get_r_value_internal (ir_node *block,
- int pos, ir_mode *mode);
-inline ir_node * new_r_Phi_in (ir_graph *irg, ir_node *block, ir_mode *mode,
- ir_node **in, int ins);
-
-/** This function computes the predecessors for a real Phi node, and then
- allocates and returns this node. The routine called to allocate the
- node might optimize it away and return a real value, or even a pointer
- to a deallocated Phi node on top of the obstack!
- This function is called with an in-array of proper size. **/
-static inline ir_node *
-phi_merge (ir_node *block, int pos, ir_mode *mode, ir_node **nin, int ins)
-{
- ir_node *prevBlock, *res;
- int i;
-
- /* This loop goes to all predecessor blocks of the block the Phi node is in
- and there finds the operands of the Phi node by calling get_r_value_internal. */
- for (i = 1; i <= ins; ++i) {
- assert (block->in[i]);
- prevBlock = block->in[i]->in[0]; /* go past control flow op to prev block */
- assert (prevBlock);
- nin[i-1] = get_r_value_internal (prevBlock, pos, mode);
- }
-
- /* After collecting all predecessors into the array nin a new Phi node
- with these predecessors is created. This constructor contains an
- optimization: If all predecessors of the Phi node are identical it
- returns the only operand instead of a new Phi node. If the value
- passes two different control flow edges without being defined, and
- this is the second path treated, a pointer to the node that will be
- allocated for the first path (recurstion) is returned. We already
- know the address of this node, as it is the next node to be allocated
- and will be placed on top of the obstack. (The obstack is a _stack_!) */
- res = new_r_Phi_in (current_ir_graph, block, mode, nin, ins);
-
- /* Now we now the value "pos" and can enter it in the array with
- all known local variables. Attention: this might be a pointer to
- a node, that later will be allocated!!! See new_r_Phi_in.
- If this is called in mature, after some set_value in the same block,
- the proper value must not be overwritten:
- The call order
- get_value (makes Phi0, put's it into graph_arr)
- set_value (overwrites Phi0 in graph_arr)
- mature_block (upgrades Phi0, puts it again into graph_arr, overwriting
- the proper value.)
- fails. */
- if (!block->attr.block.graph_arr[pos]) {
- block->attr.block.graph_arr[pos] = res;
- } else {
- // printf(" value already computed by %s\n",
- // id_to_str(block->attr.block.graph_arr[pos]->op->name));
- }
-
- return res;
+/*
+ * Copyright (C) 1995-2008 University of Karlsruhe. All right reserved.
+ *
+ * This file is part of libFirm.
+ *
+ * This file may be distributed and/or modified under the terms of the
+ * GNU General Public License version 2 as published by the Free Software
+ * Foundation and appearing in the file LICENSE.GPL included in the
+ * packaging of this file.
+ *
+ * Licensees holding valid libFirm Professional Edition licenses may use
+ * this file in accordance with the libFirm Commercial License.
+ * Agreement provided with the Software.
+ *
+ * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
+ * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE.
+ */
+
+/**
+ * @file
+ * @brief Support for ir graph modification.
+ * @author Martin Trapp, Christian Schaefer, Goetz Lindenmaier
+ * @version $Id$
+ */
+#include "config.h"
+
+#include "irvrfy.h"
+#include "irflag_t.h"
+#include "irgwalk.h"
+#include "irnode_t.h"
+#include "irgraph_t.h"
+#include "irgmod.h"
+#include "array.h"
+#include "ircons.h"
+#include "irhooks.h"
+#include "iredges_t.h"
+#include "irtools.h"
+#include "error.h"
+
+/**
+ * Turns a node into a "useless" Tuple. The Tuple just forms a tuple
+ * from several inputs.
+ * This is useful if a node returning a tuple is removed, but the Projs
+ * extracting values from the tuple are not available.
+ */
+void turn_into_tuple(ir_node *node, int arity) {
+ assert(node);
+ set_irn_op(node, op_Tuple);
+ if (get_irn_arity(node) == arity) {
+ /* keep old array */
+ } else {
+ ir_graph *irg = get_irn_irg(node);
+ ir_node *block = get_nodes_block(node);
+ edges_node_deleted(node, irg);
+ /* Allocate new array, don't free old in_array, it's on the obstack. */
+ node->in = NEW_ARR_D(ir_node *, irg->obst, arity+1);
+ /* clear the new in array, else edge_notify tries to delete garbage */
+ memset(node->in, 0, (arity+1) * sizeof(node->in[0]));
+ /* set the block back */
+ set_nodes_block(node, block);
+ }
}
-
-/* this function is used in get_r_value_internal, but defined in ircons.c */
-inline ir_node * new_r_Phi0 (ir_graph *irg, ir_node *block, ir_mode *mode);
-
-
-/* This function returns the last definition of a variable. In case
- this variable was last defined in a previous block, Phi nodes are
- inserted. If the part of the firm graph containing the definition
- is not yet constructed, a dummy Phi node is returned. */
-inline ir_node *
-get_r_value_internal (ir_node *block, int pos, ir_mode *mode)
-{
- ir_node *res;
- /* There are 4 cases to treat.
-
- 1. The block is not mature and we visit it the first time. We can not
- create a proper Phi node, therefore a Phi0, i.e., a Phi without
- predecessors is returned. This node is added to the linked list (field
- "link") of the containing block to be completed when this block is
- matured. (Comlpletion will add a new Phi and turn the Phi0 into a Id
- node.)
-
- 2. The value is already known in this block, graph_arr[pos] is set and we
- visit the block the first time. We can return the value without
- creating any new nodes.
-
- 3. The block is mature and we visit it the first time. A Phi node needs
- to be created (phi_merge). If the Phi is not needed, as all it's
- operands are the same value reaching the block through different
- paths, it's optimizes away and the value itself is returned.
-
- 4. The block is mature, and we visit it the second time. Now two
- subcases are possible:
- * The value was computed completely the last time we were here.
- This is the case if there is no loop. We can return the proper value.
- * The recursion that visited this node and set the flag did not
- return yet. We are computing a value in a loop and need to
- break the recursion without knowing the result yet.
- There is no simple check for the second subcase. Therefore we check
- for a second visit and treat all such cases as the second subcase.
- Anyways, the basic situation is the same: we reached a block
- on two paths without finding a definition of the value: No Phi
- nodes are needed on both paths.
- We return this information "Two paths, no Phi needed" by a very tricky
- implementation that relies on the fact that an obstack is a stack and
- will return a node with the same address on different allocations.
- Look also at phi_merge and get_r_phi_in to understand this.
- */
-
- /* case 4 -- already visited. */
- if (block->visit == ir_visited) return NULL;
-
- /* visited the first time */
- block->visit = ir_visited;
-
- /* Get the local valid value */
- res = block->attr.block.graph_arr[pos];
-
- /* case 2 -- If the value is actually computed, return it. */
- if (res) { return res;};
-
- if (block->attr.block.matured) { /* case 3 */
-
- /* The Phi has the same amount of ins as the corresponding block. */
- int ins = get_irn_arity(block); // ARR_LEN (block->in)-1;
- ir_node **nin;
- NEW_ARR_A (ir_node *, nin, ins);
-
- /* Phi merge collects the predecessors and then creates a node. */
- res = phi_merge (block, pos, mode, nin, ins);
-
- } else { /* case 1 */
- /* The block is not mature, we don't know how many in's are needed. A Phi
- with zero predecessors is created. Such a Phi node is called Phi0
- node. (There is also an obsolete Phi0 opcode.) The Phi0 is then added
- to the list of Phi0 nodes in this block to be matured by mature_block
- later.
- The Phi0 has to remember the pos of it's internal value. If the real Phi
- is computed, pos is used to update the array with the local values. */
-
- res = new_r_Phi0 (current_ir_graph, block, mode);
- res->attr.phi0_pos = pos;
- res->link = block->link;
- block->link = res;
- }
-
- /* If we get here, the frontend missed a use-before-definition error */
- if (!res) {
- /* Error Message */
- printf("Error: no value set\n");
- assert (mode->code >= irm_f && mode->code <= irm_p);
- res = new_r_Const (current_ir_graph, block, mode,
- tarval_mode_null[mode->code]);
- }
-
- /* The local valid value is available now. */
- block->attr.block.graph_arr[pos] = res;
-
- return res;
+/**
+ * Insert irnode `new' in place of irnode `old'
+ * Since `new' may be bigger than `old' replace `old'
+ * by an op_Id which is smaller than everything.
+ */
+void exchange(ir_node *old, ir_node *nw) {
+ ir_graph *irg;
+
+ assert(old && nw);
+ assert(old != nw && "Exchanging node with itself is not allowed");
+
+ irg = get_irn_irg(old);
+ assert(irg == get_irn_irg(nw) && "New node must be in same irg as old node");
+
+ hook_replace(old, nw);
+
+ /*
+ * If new outs are on, we can skip the id node creation and reroute
+ * the edges from the old node to the new directly.
+ */
+ if (edges_activated(irg)) {
+ /* copy all dependencies from old to new */
+ add_irn_deps(nw, old);
+
+ edges_reroute(old, nw, irg);
+ edges_reroute_kind(old, nw, EDGE_KIND_DEP, irg);
+ edges_node_deleted(old, irg);
+ old->op = op_Bad;
+ } else {
+ /* Else, do it the old-fashioned way. */
+ ir_node *block;
+
+ hook_turn_into_id(old);
+
+ block = old->in[0];
+ if (! block) {
+ block = is_Block(nw) ? nw : get_nodes_block(nw);
+
+ if (! block) {
+ panic("cannot find legal block for id");
+ }
+ }
+
+ if (get_irn_op(old)->opar == oparity_dynamic) {
+ DEL_ARR_F(get_irn_in(old));
+ }
+
+ old->op = op_Id;
+ old->in = NEW_ARR_D (ir_node *, irg->obst, 2);
+ old->in[0] = block;
+ old->in[1] = nw;
+ }
}
-
-/* add an adge to a jmp node */
-void
-add_in_edge (ir_node *block, ir_node *jmp)
-{
- if (block->attr.block.matured) {
- printf("Error: Block already matured!\n");
- }
- else {
- assert (jmp != NULL);
- ARR_APP1 (ir_node *, block->in, jmp);
- }
+/*--------------------------------------------------------------------*/
+/* Functionality for collect_phis */
+/*--------------------------------------------------------------------*/
+
+/**
+ * Walker: links all Phi nodes to their Blocks lists,
+ * all Proj nodes to there predecessors and all
+ * partBlocks to there MacroBlock header.
+ */
+static void collect_phiprojs_walker(ir_node *n, void *env) {
+ ir_node *pred;
+ (void) env;
+
+ if (is_Phi(n)) {
+ ir_node *block = get_nodes_block(n);
+ add_Block_phi(block, n);
+ } else if (is_Proj(n)) {
+ pred = n;
+ do {
+ pred = get_Proj_pred(pred);
+ } while (is_Proj(pred));
+
+ set_irn_link(n, get_irn_link(pred));
+ set_irn_link(pred, n);
+ } else if (is_Block(n)) {
+ ir_node *mbh = get_Block_MacroBlock(n);
+
+ if (mbh != n) {
+ set_irn_link(n, get_irn_link(mbh));
+ set_irn_link(mbh, n);
+ }
+ }
}
-
-/****************************/
-/* parameter administration */
-
-/* get a value from the parameter array from the current block by its index */
-ir_node *
-get_value (int pos, ir_mode *mode)
-{
- ++ir_visited;
- return get_r_value_internal (current_ir_graph->current_block, pos + 1, mode);
-}
-
-
-/* set a value at position pos in the parameter array from the current block */
-inline void
-set_value (int pos, ir_node *value)
-{
- current_ir_graph->current_block->attr.block.graph_arr[pos + 1] = value;
+void collect_phiprojs(ir_graph *irg) {
+ assert((ir_resources_reserved(irg) & (IR_RESOURCE_IRN_LINK|IR_RESOURCE_PHI_LIST)) ==
+ (IR_RESOURCE_IRN_LINK|IR_RESOURCE_PHI_LIST));
+ irg_walk_graph(irg, firm_clear_node_and_phi_links, collect_phiprojs_walker, NULL);
}
-
-/* get the current store */
-inline ir_node *
-get_store (void)
-{
- /* GL: one could call get_value instead */
- ++ir_visited;
- return get_r_value_internal (current_ir_graph->current_block, 0, mode_M);
+/*--------------------------------------------------------------------*/
+/* Functionality for part_block */
+/*--------------------------------------------------------------------*/
+
+/**
+ * Moves node and all predecessors of node from from_bl to to_bl.
+ * Does not move predecessors of Phi nodes (or block nodes).
+ */
+static void move(ir_node *node, ir_node *from_bl, ir_node *to_bl) {
+ int i, arity;
+
+ /* move this node */
+ set_nodes_block(node, to_bl);
+
+ /* move its Projs */
+ if (get_irn_mode(node) == mode_T) {
+ ir_node *proj = get_irn_link(node);
+ while (proj) {
+ if (get_nodes_block(proj) == from_bl)
+ set_nodes_block(proj, to_bl);
+ proj = get_irn_link(proj);
+ }
+ }
+
+ /* recursion ... */
+ if (is_Phi(node))
+ return;
+
+ arity = get_irn_arity(node);
+ for (i = 0; i < arity; i++) {
+ ir_node *pred = get_irn_n(node, i);
+ if (get_nodes_block(pred) == from_bl)
+ move(pred, from_bl, to_bl);
+ }
}
-
-/* set the current store */
-inline void
-set_store (ir_node *store)
-{
- /* GL: one could call set_value instead */
- current_ir_graph->current_block->attr.block.graph_arr[0] = store;
+void part_block(ir_node *node) {
+ ir_node *new_block;
+ ir_node *old_block;
+ ir_node *phi;
+ ir_node *mbh;
+ ir_node *next, *block;
+
+ /* Turn off optimizations so that blocks are not merged again. */
+ int rem_opt = get_opt_optimize();
+ set_optimize(0);
+
+ /* Transform the control flow */
+ old_block = get_nodes_block(node);
+ mbh = get_Block_MacroBlock(old_block);
+ new_block = new_Block(get_Block_n_cfgpreds(old_block),
+ get_Block_cfgpred_arr(old_block));
+
+ if (mbh != old_block) {
+ /* we splitting a partBlock */
+ set_Block_MacroBlock(new_block, mbh);
+ } else {
+ /* we are splitting a header: this creates a new header */
+ set_Block_MacroBlock(new_block, new_block);
+ }
+ set_irg_current_block(current_ir_graph, new_block);
+ {
+ ir_node *jmp = new_Jmp();
+ set_irn_in(old_block, 1, &jmp);
+ irn_vrfy_irg(old_block, current_ir_graph);
+ }
+
+ /* move node and its predecessors to new_block */
+ move(node, old_block, new_block);
+
+ /* move Phi nodes to new_block */
+ phi = get_Block_phis(old_block);
+ set_Block_phis(new_block, phi);
+ set_Block_phis(old_block, NULL);
+ while (phi) {
+ set_nodes_block(phi, new_block);
+ phi = get_Phi_next(phi);
+ }
+
+ /* rewire partBlocks */
+ if (mbh != old_block) {
+ ir_node *list = NULL;
+
+ /* move blocks from mbh to old_block if old_block dominates them */
+ block = get_irn_link(mbh);
+
+ set_irn_link(mbh, NULL);
+ set_Block_MacroBlock(old_block, old_block);
+
+ /* note that we must splice the list of partBlock here */
+ for (; block != NULL; block = next) {
+ ir_node *curr = block;
+ assert(is_Block(curr));
+
+ next = get_irn_link(block);
+
+ if (block == old_block)
+ continue;
+
+ assert(get_Block_MacroBlock(curr) == mbh);
+
+ for (;;) {
+ if (curr == old_block) {
+ /* old_block dominates the block, so old_block will be
+ the new macro block header */
+ set_Block_MacroBlock(block, old_block);
+ set_irn_link(block, list);
+ list = block;
+ break;
+ }
+ if (curr == mbh) {
+ /* leave it in the mbh */
+ set_irn_link(block, get_irn_link(mbh));
+ set_irn_link(mbh, block);
+ break;
+ }
+
+ assert(get_Block_n_cfgpreds(curr) == 1);
+ curr = get_Block_cfgpred_block(curr, 0);
+ }
+ }
+ /* beware: do NOT directly manipulate old_block's list, as old_block is
+ in mbh's list and this would destroy the list! */
+ set_irn_link(old_block, list);
+
+ /* finally add new_block to mbh's list */
+ set_irn_link(new_block, get_irn_link(mbh));
+ set_irn_link(mbh, new_block);
+ } else {
+ /* move blocks from mbh to new_block */
+ block = get_irn_link(mbh);
+
+ set_irn_link(mbh, NULL);
+ set_irn_link(new_block, NULL);
+
+ for (; block != NULL; block = next) {
+ next = get_irn_link(block);
+
+ set_Block_MacroBlock(block, new_block);
+ set_irn_link(block, get_irn_link(new_block));
+ set_irn_link(new_block, block);
+ }
+ }
+
+ set_optimize(rem_opt);
}
-/** Finalize a Block node, when all control flows are known. */
-/** Acceptable parameters are only Block nodes. */
-void
-mature_block (ir_node *block)
-{
-
- int ins;
- ir_node *n, **nin;
- ir_node *next;
-
- assert (get_irn_opcode(block) == iro_Block);
-
- if (!get_Block_matured(block)) {
-
- /* turn the dynamic in-array into a static one. */
- ins = ARR_LEN (block->in)-1;
- NEW_ARR_A (ir_node *, nin, ins);
-
- /* GL, 7.2.2000. seems to be not complete. added this: but does'nt work.*
- memcpy (nin, block->in, sizeof (ir_node *) * ins);
- block->in = nin;
- */
-
- /* Traverse a chain of Phi nodes attached to this block and mature these, too. **/
- for (n = block->link; n; n=next) {
- ir_visited++;
- next = n->link;
- exchange (n, phi_merge (block, n->attr.phi0_pos, n->mode, nin, ins));
- }
-
- block->attr.block.matured = 1;
-
- block = optimize_in_place(block);
- ir_vrfy(block);
- }
-
-}
-
-/* changing the current block */
-void
-switch_block (ir_node *target)
-{
- current_ir_graph->current_block = target;
-}
-
-
-void
-turn_into_tuple (ir_node *node, int arity)
-{
- assert(node);
- set_irn_op(node, op_Tuple);
- if (get_irn_arity(node) == arity) {
- /* keep old array */
- } else {
- /* allocate new array, remove old one. */
- /* !!!??? free old in_array */
- node->in = NEW_ARR_D (ir_node *, current_ir_graph->obst, arity+1);
- }
-}
-
-
-
-/* Insert irnode `new' in place of irnode `old'
- Since `new' may be bigger than `old' replace `old'
- by an op_Id which is smaller than everything */
-inline void
-exchange (ir_node *old, ir_node *new)
-{
- ir_node *block = old->in[0];
+/* kill a node by setting its predecessors to Bad and finally exchange the node by Bad itself. */
+void kill_node(ir_node *node) {
+ ir_graph *irg = get_irn_irg(node);
+ ir_node *bad = get_irg_bad(irg);
+ int i;
- old->op = op_Id;
- old->in = NEW_ARR_D (ir_node *, current_ir_graph->obst, 2);
- old->in[0] = block;
- old->in[1] = new;
+ for (i = get_irn_arity(node) - 1; i >= -1; --i) {
+ set_irn_n(node, i, bad);
+ }
+ exchange(node, bad);
}