-/* Coyright (C) 1998 - 2000 by Universitaet Karlsruhe
-** All rights reserved.
-**
-** Author: Christian Schaefer
-**
-** Optimizations for a whole ir graph, i.e., a procedure.
+/* Coyright (C) 1998 - 2002 by Universitaet Karlsruhe
+* All rights reserved.
+*
+* Author: Christian Schaefer, Goetz Lindenmaier, Sebastian Felis
+*
+* Optimizations for a whole ir graph, i.e., a procedure.
*/
/* $Id$ */
# include "pset.h"
# include "pdeq.h" /* Fuer code placement */
# include "irouts.h"
+# include "irloop.h"
+# include "irbackedge_t.h"
/* Defined in iropt.c */
pset *new_identities (void);
/* apply optimizations of iropt to all nodes. */
/********************************************************************/
-void init_link (ir_node *n, void *env) {
+static void init_link (ir_node *n, void *env) {
set_irn_link(n, NULL);
}
-void
+static void
optimize_in_place_wrapper (ir_node *n, void *env) {
int i;
- ir_node *optimized;
+ ir_node *optimized, *old;
for (i = 0; i < get_irn_arity(n); i++) {
- optimized = optimize_in_place_2(get_irn_n(n, i));
+ /* get?irn_n skips Id nodes, so comparison old != optimized does not
+ show all optimizations. Therefore always set new predecessor. */
+ old = get_irn_n(n, i);
+ optimized = optimize_in_place_2(old);
set_irn_n(n, i, optimized);
}
/********************************************************************/
/* Remeber the new node in the old node by using a field all nodes have. */
-inline void
+static INLINE void
set_new_node (ir_node *old, ir_node *new)
{
old->link = new;
}
/* Get this new node, before the old node is forgotton.*/
-inline ir_node *
+static INLINE ir_node *
get_new_node (ir_node * n)
{
return n->link;
Remembering the arity is useful, as it saves a lot of pointer
accesses. This function is called for all Phi and Block nodes
in a Block. */
-inline int
+static INLINE int
compute_new_arity(ir_node *b) {
int i, res;
int irg_v, block_v;
}
}
+static INLINE void new_backedge_info(ir_node *n) {
+ switch(get_irn_opcode(n)) {
+ case iro_Block:
+ n->attr.block.cg_backedge = NULL;
+ n->attr.block.backedge = new_backedge_arr(current_ir_graph->obst, get_irn_arity(n));
+ break;
+ case iro_Phi:
+ n->attr.phi_backedge = new_backedge_arr(current_ir_graph->obst, get_irn_arity(n));
+ break;
+ case iro_Filter:
+ n->attr.filter.backedge = new_backedge_arr(current_ir_graph->obst, get_irn_arity(n));
+ break;
+ default: ;
+ }
+}
+
/* Copies the node to the new obstack. The Ins of the new node point to
the predecessors on the old obstack. For block/phi nodes not all
predecessors might be copied. n->link points to the new node.
For Phi and Block nodes the function allocates in-arrays with an arity
only for useful predecessors. The arity is determined by counting
the non-bad predecessors of the block. */
-void
+static void
copy_node (ir_node *n, void *env) {
ir_node *nn, *block;
int new_arity;
if (get_irn_opcode(n) == iro_Block) {
block = NULL;
new_arity = compute_new_arity(n);
+ n->attr.block.graph_arr = NULL;
} else {
block = get_nodes_Block(n);
if (get_irn_opcode(n) == iro_Phi) {
was allocated on the old obstack the pointers now are dangling. This
frees e.g. the memory of the graph_arr allocated in new_immBlock. */
copy_attrs(n, nn);
+ new_backedge_info(nn);
set_new_node(n, nn);
/* printf("\n old node: "); DDMSG2(n);
/* Copies new predecessors of old node to new node remembered in link.
Spare the Bad predecessors of Phi and Block nodes. */
-void
+static void
copy_preds (ir_node *n, void *env) {
ir_node *nn, *block;
int i, j;
for (i = 0; i < get_irn_arity(n); i++)
if (get_irn_opcode(get_irn_n(n, i)) != iro_Bad) {
set_irn_n (nn, j, get_new_node(get_irn_n(n, i)));
+ //if (is_backedge(n, i)) set_backedge(nn, j);
j++;
}
/* repair the block visited flag from above misuse. Repair it in both
in array contained Bads. Now it's possible.
We don't call optimize_in_place as it requires
that the fields in ir_graph are set properly. */
- if (get_Block_n_cfgpreds(nn) == 1
- && get_irn_op(get_Block_cfgpred(nn, 0)) == op_Jmp)
+ if ((get_opt_control_flow_straightening()) &&
+ (get_Block_n_cfgpreds(nn) == 1) &&
+ (get_irn_op(get_Block_cfgpred(nn, 0)) == op_Jmp))
exchange(nn, get_nodes_Block(get_Block_cfgpred(nn, 0)));
} else if (get_irn_opcode(n) == iro_Phi) {
/* Don't copy node if corresponding predecessor in block is Bad.
for (i = 0; i < get_irn_arity(n); i++)
if (get_irn_opcode(get_irn_n(block, i)) != iro_Bad) {
set_irn_n (nn, j, get_new_node(get_irn_n(n, i)));
+ //if (is_backedge(n, i)) set_backedge(nn, j);
j++;
}
/* If the pre walker reached this Phi after the post walker visited the
}
/* Copies the graph recursively, compacts the keepalive of the end node. */
-void
-copy_graph () {
+static void
+copy_graph (void) {
ir_node *oe, *ne; /* old end, new end */
ir_node *ka; /* keep alive */
int i;
in current_ir_graph and fixes the environment.
Then fixes the fields in current_ir_graph containing nodes of the
graph. */
-void
-copy_graph_env () {
+static void
+copy_graph_env (void) {
+ ir_node *old_end;
/* Not all nodes remembered in current_ir_graph might be reachable
from the end node. Assure their link is set to NULL, so that
we can test whether new nodes have been computed. */
copy_graph();
/* fix the fields in current_ir_graph */
- free_End(get_irg_end(current_ir_graph));
- set_irg_end (current_ir_graph, get_new_node(get_irg_end(current_ir_graph)));
+ old_end = get_irg_end(current_ir_graph);
+ set_irg_end (current_ir_graph, get_new_node(old_end));
+ free_End(old_end);
set_irg_end_block (current_ir_graph, get_new_node(get_irg_end_block(current_ir_graph)));
if (get_irn_link(get_irg_frame(current_ir_graph)) == NULL) {
copy_node (get_irg_frame(current_ir_graph), NULL);
assert(get_irg_phase_state(current_ir_graph) != phase_building);
free_outs(current_ir_graph);
+ /* @@@ so far we loose loops when copying */
+ set_irg_loop(current_ir_graph, NULL);
+
if (get_optimize() && get_opt_dead_node_elimination()) {
/* A quiet place, where the old obstack can rest in peace,
current_ir_graph = rem;
}
+/* Relink bad predeseccors of a block and store the old in array to the
+ link field. This function is called by relink_bad_predecessors().
+ The array of link field starts with the block operand at position 0.
+ If block has bad predecessors, create a new in array without bad preds.
+ Otherwise let in array untouched. */
+static void relink_bad_block_predecessors(ir_node *n, void *env) {
+ ir_node **new_in, *irn;
+ int i, new_irn_n, old_irn_arity, new_irn_arity = 0;
+
+ /* if link field of block is NULL, look for bad predecessors otherwise
+ this is allready done */
+ if (get_irn_op(n) == op_Block &&
+ get_irn_link(n) == NULL) {
+
+ /* save old predecessors in link field (position 0 is the block operand)*/
+ set_irn_link(n, (void *)get_irn_in(n));
+
+ /* count predecessors without bad nodes */
+ old_irn_arity = get_irn_arity(n);
+ for (i = 0; i < old_irn_arity; i++)
+ if (!is_Bad(get_irn_n(n, i))) new_irn_arity++;
+
+ /* arity changing: set new predecessors without bad nodes */
+ if (new_irn_arity < old_irn_arity) {
+ /* get new predecessor array without Block predecessor */
+ new_in = NEW_ARR_D (ir_node *, current_ir_graph->obst, (new_irn_arity+1));
+
+ /* set new predeseccors in array */
+ new_in[0] = NULL;
+ new_irn_n = 1;
+ for (i = 1; i < old_irn_arity; i++) {
+ irn = get_irn_n(n, i);
+ if (!is_Bad(irn)) new_in[new_irn_n++] = irn;
+ }
+ n->in = new_in;
+ } /* ir node has bad predecessors */
+
+ } /* Block is not relinked */
+}
+
+/* Relinks Bad predecesors from Bocks and Phis called by walker
+ remove_bad_predecesors(). If n is a Block, call
+ relink_bad_block_redecessors(). If n is a Phinode, call also the relinking
+ function of Phi's Block. If this block has bad predecessors, relink preds
+ of the Phinode. */
+static void relink_bad_predecessors(ir_node *n, void *env) {
+ ir_node *block, **old_in;
+ int i, old_irn_arity, new_irn_arity;
+
+ /* relink bad predeseccors of a block */
+ if (get_irn_op(n) == op_Block)
+ relink_bad_block_predecessors(n, env);
+
+ /* If Phi node relink its block and its predecessors */
+ if (get_irn_op(n) == op_Phi) {
+
+ /* Relink predeseccors of phi's block */
+ block = get_nodes_Block(n);
+ if (get_irn_link(block) == NULL)
+ relink_bad_block_predecessors(block, env);
+
+ old_in = (ir_node **)get_irn_link(block); /* Of Phi's Block */
+ old_irn_arity = ARR_LEN(old_in);
+
+ /* Relink Phi predeseccors if count of predeseccors changed */
+ if (old_irn_arity != ARR_LEN(get_irn_in(block))) {
+ /* set new predeseccors in array
+ n->in[0] remains the same block */
+ new_irn_arity = 1;
+ for(i = 1; i < old_irn_arity; i++)
+ if (!is_Bad((ir_node *)old_in[i])) n->in[new_irn_arity++] = n->in[i];
+
+ ARR_SETLEN(ir_node *, n->in, new_irn_arity);
+ }
+
+ } /* n is a Phi node */
+}
+
+/* Removes Bad Bad predecesors from Blocks and the corresponding
+ inputs to Phi nodes as in dead_node_elimination but without
+ copying the graph.
+ On walking up set the link field to NULL, on walking down call
+ relink_bad_predecessors() (This function stores the old in array
+ to the link field and sets a new in array if arity of predecessors
+ changes) */
+void remove_bad_predecessors(ir_graph *irg) {
+ irg_walk_graph(irg, init_link, relink_bad_predecessors, NULL);
+}
+
+
/**********************************************************************/
/* Funcionality for inlining */
/**********************************************************************/
then updates the entity if it's a local one. env must be a pointer
to the frame type of the procedure. The new entities must be in
the link field of the entities. */
-void
+static INLINE void
copy_node_inline (ir_node *n, void *env) {
ir_node *new;
type *frame_tp = (type *)env;
ir_node **res_pred;
ir_node **cf_pred;
ir_node *ret, *phi;
- ir_node *cf_op, *bl;
+ ir_node *cf_op = NULL, *bl;
int arity, n_ret, n_exc, n_res, i, j, rem_opt;
type *called_frame;
if (!get_optimize() || !get_opt_inline()) return;
- /** Turn off optimizations, this can cause problems when allocating new nodes. **/
+ /* -- Turn off optimizations, this can cause problems when allocating new nodes. -- */
rem_opt = get_optimize();
set_optimize(0);
if (get_irg_outs_state(current_ir_graph) == outs_consistent)
set_irg_outs_inconsistent(current_ir_graph);
- /** Check preconditions **/
+ /* -- Check preconditions -- */
assert(get_irn_op(call) == op_Call);
- assert(get_Call_type(call) == get_entity_type(get_irg_ent(called_graph)));
+ /* @@@ does not work for InterfaceIII.java after cgana
+ assert(get_Call_type(call) == get_entity_type(get_irg_ent(called_graph)));
+ assert(smaller_type(get_entity_type(get_irg_ent(called_graph)),
+ get_Call_type(call)));
+ */
assert(get_type_tpop(get_Call_type(call)) == type_method);
- if (called_graph == current_ir_graph) return;
-
+ if (called_graph == current_ir_graph) {
+ set_optimize(rem_opt);
+ return;
+ }
- /** Part the Call node into two nodes. Pre_call collects the parameters of
- the procedure and later replaces the Start node of the called graph.
- Post_call is the old Call node and collects the results of the called
- graph. Both will end up being a tuple. **/
+ /* --
+ the procedure and later replaces the Start node of the called graph.
+ Post_call is the old Call node and collects the results of the called
+ graph. Both will end up being a tuple. -- */
post_bl = get_nodes_Block(call);
set_irg_current_block(current_ir_graph, post_bl);
/* XxMxPxP of Start + parameter of Call */
pre_call = new_Tuple(5, in);
post_call = call;
- /** Part the block of the Call node into two blocks.
+ /* --
The new block gets the ins of the old block, pre_call and all its
- predecessors and all Phi nodes. **/
+ predecessors and all Phi nodes. -- */
part_block(pre_call);
- /** Prepare state for dead node elimination **/
+ /* -- Prepare state for dead node elimination -- */
/* Visited flags in calling irg must be >= flag in called irg.
Else walker and arity computation will not work. */
if (get_irg_visited(current_ir_graph) <= get_irg_visited(called_graph))
- set_irg_visited(current_ir_graph, get_irg_visited(called_graph)+1); /***/
+ set_irg_visited(current_ir_graph, get_irg_visited(called_graph)+1);
if (get_irg_block_visited(current_ir_graph)< get_irg_block_visited(called_graph))
set_irg_block_visited(current_ir_graph, get_irg_block_visited(called_graph));
/* Set pre_call as new Start node in link field of the start node of
copying. */
set_irn_link(get_irg_start(called_graph), pre_call);
set_irn_visited(get_irg_start(called_graph),
- get_irg_visited(current_ir_graph));/***/
+ get_irg_visited(current_ir_graph));
set_irn_link(get_irg_start_block(called_graph),
- get_nodes_Block(pre_call));
+ get_nodes_Block(pre_call));
set_irn_visited(get_irg_start_block(called_graph),
- get_irg_visited(current_ir_graph)); /***/
+ get_irg_visited(current_ir_graph));
/* Initialize for compaction of in arrays */
inc_irg_block_visited(current_ir_graph);
- /*
- set_Block_block_visited(get_irg_start_block(called_graph),
- get_irg_block_visited(current_ir_graph) +1 +1); /* count for self edge */
- /*** Replicate local entities of the called_graph ***/
+ /* -- Replicate local entities of the called_graph -- */
/* copy the entities. */
called_frame = get_irg_frame_type(called_graph);
- for (i = 0; i < get_class_n_member(called_frame); i++) {
+ for (i = 0; i < get_class_n_members(called_frame); i++) {
entity *new_ent, *old_ent;
old_ent = get_class_member(called_frame, i);
new_ent = copy_entity_own(old_ent, get_cur_frame_type());
to inline, calling this inline will not visit the inlined nodes. */
set_irg_visited(current_ir_graph, get_irg_visited(current_ir_graph)-1);
- /** Performing dead node elimination inlines the graph **/
+ /* -- Performing dead node elimination inlines the graph -- */
/* Copies the nodes to the obstack of current_ir_graph. Updates links to new
entities. */
- /* @@@ endless loops are not copied!! */
+ /* @@@ endless loops are not copied!! -- they should be, I think... */
irg_walk(get_irg_end(called_graph), copy_node_inline, copy_preds,
get_irg_frame_type(called_graph));
set_irg_block_visited(called_graph, get_irg_block_visited(current_ir_graph));
set_Block_block_visited(get_irg_start_block(called_graph), 0);
- /*** Merge the end of the inlined procedure with the call site ***/
+ /* -- Merge the end of the inlined procedure with the call site -- */
/* We will turn the old Call node into a Tuple with the following
predecessors:
-1: Block of Tuple.
3: Phi of Exception memories.
*/
- /** Precompute some values **/
+ /* -- Precompute some values -- */
end_bl = get_new_node(get_irg_end_block(called_graph));
end = get_new_node(get_irg_end(called_graph));
arity = get_irn_arity(end_bl); /* arity = n_exc + n_ret */
- n_res = get_method_n_res(get_Call_type(call));
+ n_res = get_method_n_ress(get_Call_type(call));
res_pred = (ir_node **) malloc (n_res * sizeof (ir_node *));
cf_pred = (ir_node **) malloc (arity * sizeof (ir_node *));
set_irg_current_block(current_ir_graph, post_bl); /* just to make sure */
- /** archive keepalives **/
+ /* -- archive keepalives -- */
for (i = 0; i < get_irn_arity(end); i++)
add_End_keepalive(get_irg_end(current_ir_graph), get_irn_n(end, i));
/* The new end node will die, but the in array is not on the obstack ... */
free_End(end);
- /** Collect control flow from Return blocks to post_calls block. Replace
- Return nodes by Jump nodes. **/
+/* --
+ Return nodes by Jump nodes. -- */
n_ret = 0;
for (i = 0; i < arity; i++) {
ir_node *ret;
}
set_irn_in(post_bl, n_ret, cf_pred);
- /** Collect results from Return nodes to post_call. Post_call is
- turned into a tuple. **/
+/* --
+ turned into a tuple. -- */
turn_into_tuple(post_call, 4);
/* First the Memory-Phi */
n_ret = 0;
}
phi = new_Phi(n_ret, cf_pred, mode_M);
set_Tuple_pred(call, 0, phi);
- set_irn_link(phi, get_irn_link(post_bl)); /* Conserve Phi-list for further inlinings */
- set_irn_link(post_bl, phi);
+ /* Conserve Phi-list for further inlinings -- but might be optimized */
+ if (get_nodes_Block(phi) == post_bl) {
+ set_irn_link(phi, get_irn_link(post_bl));
+ set_irn_link(post_bl, phi);
+ }
/* Now the real results */
if (n_res > 0) {
for (j = 0; j < n_res; j++) {
}
phi = new_Phi(n_ret, cf_pred, get_irn_mode(cf_pred[0]));
res_pred[j] = phi;
- set_irn_link(phi, get_irn_link(post_bl)); /* Conserve Phi-list for further inlinings */
- set_irn_link(post_bl, phi);
+ /* Conserve Phi-list for further inlinings -- but might be optimized */
+ if (get_nodes_Block(phi) == post_bl) {
+ set_irn_link(phi, get_irn_link(post_bl));
+ set_irn_link(post_bl, phi);
+ }
}
set_Tuple_pred(call, 2, new_Tuple(n_res, res_pred));
} else {
}
}
if (n_exc > 0) {
- new_Block(n_exc, cf_pred); /* whatch it: current_block is changed! */
+ new_Block(n_exc, cf_pred); /* watch it: current_block is changed! */
set_Tuple_pred(call, 1, new_Jmp());
/* The Phi for the memories with the exception objects */
n_exc = 0;
free(res_pred);
free(cf_pred);
- /*** Correct the control flow to the end node.
+/* --
If the exception control flow from the Call directly branched to the
end block we now have the following control flow predecessor pattern:
ProjX -> Tuple -> Jmp.
We must remove the Jmp along with it's empty block and add Jmp's
- predecessors as predecessors of this end block. ***/
+ predecessors as predecessors of this end block. -- */
/* find the problematic predecessor of the end block. */
end_bl = get_irg_end_block(current_ir_graph);
for (i = 0; i < get_Block_n_cfgpreds(end_bl); i++) {
free(cf_pred);
}
- /** Turn cse back on. **/
+ /* -- Turn cse back on. -- */
set_optimize(rem_opt);
}
if (get_irn_op(addr) == op_Const) {
/* Check whether the constant is the pointer to a compiled entity. */
tv = get_Const_tarval(addr);
- if (tv->u.p.ent) {
- called_irg = get_entity_irg(tv->u.p.ent);
+ if (tarval_to_entity(tv)) {
+ called_irg = get_entity_irg(tarval_to_entity(tv));
if (called_irg && pos < MAX_INLINE) {
/* The Call node calls a locally defined method. Remember to inline. */
calls[pos] = call;
}
}
-
/* Inlines all small methods at call sites where the called address comes
from a Const node that references the entity representing the called
method.
if (!(get_optimize() && get_opt_inline())) return;
- /*DDME(get_irg_ent(current_ir_graph));*/
-
current_ir_graph = irg;
/* Handle graph state */
assert(get_irg_phase_state(current_ir_graph) != phase_building);
tarval *tv;
ir_graph *callee;
tv = get_Const_tarval(get_Call_ptr(calls[i]));
- callee = get_entity_irg(tv->u.p.ent);
+ callee = get_entity_irg(tarval_to_entity(tv));
if ((_obstack_memory_used(callee->obst) - obstack_room(callee->obst)) < size) {
- /*printf(" inlineing "); DDME(tv->u.p.ent);*/
inline_method(calls[i], callee);
}
}
Start, Call and end at pinned nodes as Store, Call. Place_early
places all floating nodes reachable from its argument through floating
nodes and adds all beginnings at pinned nodes to the worklist. */
-inline void place_early () {
+static INLINE void place_early (void) {
assert(worklist);
inc_irg_visited(current_ir_graph);
static ir_node *
consumer_dom_dca (ir_node *dca, ir_node *consumer, ir_node *producer)
{
- ir_node *block;
+ ir_node *block = NULL;
/* Compute the latest block into which we can place a node so that it is
before consumer. */
return dca;
}
-#if 0
-/* @@@ Needs loop informations. Will implement later interprocedural. */
+static INLINE int get_irn_loop_depth(ir_node *n) {
+ return get_loop_depth(get_irn_loop(n));
+}
+
+/* Move n to a block with less loop depth than it's current block. The
+ new block must be dominated by early. */
static void
-move_out_of_loops (ir_node *n, ir_node *dca)
+move_out_of_loops (ir_node *n, ir_node *early)
{
- assert(dca);
+ ir_node *best, *dca;
+ assert(n && early);
+
/* Find the region deepest in the dominator tree dominating
dca with the least loop nesting depth, but still dominated
by our early placement. */
- ir_node *best = dca;
- while (dca != get_nodes_Block(n)) {
+ dca = get_nodes_Block(n);
+ best = dca;
+ while (dca != early) {
dca = get_Block_idom(dca);
if (!dca) break; /* should we put assert(dca)? */
- if (get_Block_loop_depth(dca) < get_Block_loop_depth(best)) {
+ if (get_irn_loop_depth(dca) < get_irn_loop_depth(best)) {
best = dca;
}
}
- if (get_Block_dom_depth(best) >= get_Block_dom_depth(get_nodes_Block(n)))
+ if (best != get_nodes_Block(n)) {
+ /* debug output
+ printf("Moving out of loop: "); DDMN(n);
+ printf(" Outermost block: "); DDMN(early);
+ printf(" Best block: "); DDMN(best);
+ printf(" Innermost block: "); DDMN(get_nodes_Block(n));
+ */
set_nodes_Block(n, best);
+ }
}
-#endif
/* Find the latest legal block for N and place N into the
`optimal' Block between the latest and earliest legal block.
place_floats_late (ir_node *n)
{
int i;
+ ir_node *early;
assert (irn_not_visited(n)); /* no multiple placement */
/* no need to place block nodes, control nodes are already placed. */
- if ((get_irn_op(n) != op_Block) && (!is_cfop(n)) && (get_irn_mode(n) != mode_X)) {
+ if ((get_irn_op(n) != op_Block) &&
+ (!is_cfop(n)) &&
+ (get_irn_mode(n) != mode_X)) {
+ /* Remember the early palacement of this block to move it
+ out of loop no further than the early placement. */
+ early = get_nodes_Block(n);
/* Assure that our users are all placed, except the Phi-nodes.
--- Each dataflow cycle contains at least one Phi-node. We
have to break the `user has to be placed before the
place_floats_late (succ);
}
- /* We have to determine the final block of this node... except for constants. */
+ /* We have to determine the final block of this node... except for
+ constants. */
if ((get_op_pinned(get_irn_op(n)) == floats) &&
(get_irn_op(n) != op_Const) &&
(get_irn_op(n) != op_SymConst)) {
dca = consumer_dom_dca (dca, get_irn_out(n, i), n);
}
set_nodes_Block(n, dca);
-#if 0
- move_out_of_loops (n, dca);
-#endif
+
+ move_out_of_loops (n, early);
}
}
}
}
-inline void place_late() {
+static INLINE void place_late(void) {
assert(worklist);
inc_irg_visited(current_ir_graph);
if (get_irg_dom_state(irg) != dom_consistent)
compute_doms(irg);
+ construct_backedges(irg);
+
/* Place all floating nodes as early as possible. This guarantees
a legal code placement. */
worklist = new_pdeq ();
/* Control flow optimization. */
/* Removes Bad control flow predecessors and empty blocks. A block */
/* is empty if it contains only a Jmp node. */
-/* */
+/* Blocks can only be removed if they are not needed for the */
+/* semantics of Phi nodes. */
/********************************************************************/
-
+/* Removes Tuples from Block control flow predecessors.
+ Optimizes blocks with equivalent_node().
+ Replaces n by Bad if n is unreachable control flow. */
static void merge_blocks(ir_node *n, void *env) {
int i;
set_irn_link(n, NULL);
if (get_irn_op(n) == op_Block) {
/* Remove Tuples */
for (i = 0; i < get_Block_n_cfgpreds(n); i++)
- set_Block_cfgpred(n, i, skip_Tuple(get_Block_cfgpred(n, i)));
- } else if (get_irn_mode(n) == mode_X) {
+ /* GL @@@ : is this possible? if (get_opt_normalize()) -- added, all tests go throug.
+ A different order of optimizations might cause problems. */
+ if (get_opt_normalize())
+ set_Block_cfgpred(n, i, skip_Tuple(get_Block_cfgpred(n, i)));
+ } else if (get_optimize() && (get_irn_mode(n) == mode_X)) {
/* We will soon visit a block. Optimize it before visiting! */
ir_node *b = get_nodes_Block(n);
ir_node *new = equivalent_node(b);
while (irn_not_visited(b) && (!is_Bad(new)) && (new != b)) {
- /* We would have to run gigo if new is bad. */
- if (get_optimize() && get_opt_control_flow()) exchange (b, new);
+ /* We would have to run gigo if new is bad, so we
+ promote it directly below. */
+ assert(((b == new) || get_opt_control_flow_straightening() || get_opt_control_flow_weak_simplification()) &&
+ ("strange flag setting"));
+ exchange (b, new);
b = new;
new = equivalent_node(b);
}
- if (is_Bad(new)) exchange (n, new_Bad());
+ /* GL @@@ get_opt_normalize hinzugefuegt, 5.5.2003 */
+ if (is_Bad(new) && get_opt_normalize()) exchange (n, new_Bad());
}
}
+/* Collects all Phi nodes in link list of Block.
+ Marks all blocks "block_visited" if they contain a node other
+ than Jmp. */
static void collect_nodes(ir_node *n, void *env) {
if (is_no_Block(n)) {
ir_node *b = get_nodes_Block(n);
}
/* Returns true if pred is pred of block */
-int is_pred_of(ir_node *pred, ir_node *b) {
+static int is_pred_of(ir_node *pred, ir_node *b) {
int i;
for (i = 0; i < get_Block_n_cfgpreds(b); i++) {
ir_node *b_pred = get_nodes_Block(get_Block_cfgpred(b, i));
return 0;
}
-int test_whether_dispensable(ir_node *b, int pos) {
+static int test_whether_dispensable(ir_node *b, int pos) {
int i, j, n_preds = 1;
int dispensable = 1;
ir_node *cfop = get_Block_cfgpred(b, pos);
if (get_Block_block_visited(pred) + 1
< get_irg_block_visited(current_ir_graph)) {
- if (!get_optimize() || !get_opt_control_flow()) {
+ if (!get_optimize() || !get_opt_control_flow_strong_simplification()) {
/* Mark block so that is will not be removed. */
set_Block_block_visited(pred, get_irg_block_visited(current_ir_graph)-1);
return 1;
return n_preds;
}
-void optimize_blocks(ir_node *b, void *env) {
+static void optimize_blocks(ir_node *b, void *env) {
int i, j, k, max_preds, n_preds;
ir_node *pred, *phi;
ir_node **in;
+ /* Count the number of predecessor if this block is merged with pred blocks
+ that are empty. */
max_preds = 0;
for (i = 0; i < get_Block_n_cfgpreds(b); i++) {
- pred = get_Block_cfgpred(b, i);
max_preds += test_whether_dispensable(b, i);
}
in = (ir_node **) malloc(max_preds * sizeof(ir_node *));
-
- /** Debug output **
+/**
printf(" working on "); DDMN(b);
for (i = 0; i < get_Block_n_cfgpreds(b); i++) {
pred = get_nodes_Block(get_Block_cfgpred(b, i));
printf(" removing pred %i ", i); DDMN(pred);
} else { printf(" Nothing to do for "); DDMN(pred); }
}
- ** end Debug output **/
+ * end Debug output **/
/** Fix the Phi nodes **/
phi = get_irn_link(b);
}
n_preds++;
}
-#if 0
- /* @@@ hier brauche ich schleifeninformation!!! Wenn keine Rueckwaertskante
- dann darfs auch keine Verwendung geben. */
+ /* The Phi_pred node is replaced now if it is a Phi.
+ In Schleifen kann offenbar der entfernte Phi Knoten legal verwendet werden.
+ Daher muss der Phiknoten durch den neuen ersetzt werden.
+ Weiter muss der alte Phiknoten entfernt werden (durch ersetzen oder
+ durch einen Bad) damit er aus den keep_alive verschwinden kann.
+ Man sollte also, falls keine Schleife vorliegt, exchange mit new_Bad
+ aufrufen. */
if (get_nodes_Block(phi_pred) == pred) {
/* remove the Phi as it might be kept alive. Further there
might be other users. */
- exchange(phi_pred, phi); /* geht, is aber doch semantisch falsch! */
+ exchange(phi_pred, phi); /* geht, ist aber doch semantisch falsch! Warum?? */
}
-#endif
} else {
in[n_preds] = get_Phi_pred(phi, i);
n_preds ++;
}
/* Fix the node */
set_irn_in(phi, n_preds, in);
+
phi = get_irn_link(phi);
}
- /** Move Phi nodes from removed blocks to this one.
+/**
This happens only if merge between loop backedge and single loop entry. **/
for (k = 0; k < get_Block_n_cfgpreds(b); k++) {
pred = get_nodes_Block(get_Block_cfgpred(b, k));
< get_irg_block_visited(current_ir_graph)) {
/* It's an empty block and not yet visited. */
for (j = 0; j < get_Block_n_cfgpreds(pred); j++) {
- /* @@@ Hier brauche ich schleifeninformation!!! Kontrllflusskante
+ /* @@@ Hier brauche ich Schleifeninformation!!! Kontrollflusskante
muss Rueckwaertskante sein! (An allen vier in[n_preds] = phi
Anweisungen.) Trotzdem tuts bisher!! */
in[n_preds] = phi;
ir_graph *rem = current_ir_graph;
current_ir_graph = irg;
-
/* Handle graph state */
assert(get_irg_phase_state(irg) != phase_building);
if (get_irg_outs_state(current_ir_graph) == outs_consistent)
if (get_irg_dom_state(current_ir_graph) == dom_consistent)
set_irg_dom_inconsistent(current_ir_graph);
- //DDME(get_irg_ent(irg));
-
/* Use block visited flag to mark non-empty blocks. */
inc_irg_block_visited(irg);
irg_walk(end, merge_blocks, collect_nodes, NULL);
for end if useful. */
in = NEW_ARR_F (ir_node *, 1);
in[0] = get_nodes_Block(end);
-
inc_irg_visited(current_ir_graph);
for(i = 0; i < get_End_n_keepalives(end); i++) {
ir_node *ka = get_End_keepalive(end, i);
- if (irn_not_visited(ka))
+ if (irn_not_visited(ka)) {
if ((get_irn_op(ka) == op_Block) && Block_not_block_visited(ka)) {
set_irg_block_visited(current_ir_graph, /* Don't walk all the way to Start. */
get_irg_block_visited(current_ir_graph)-1);
ARR_APP1 (ir_node *, in, ka);
}
}
+ }
/* DEL_ARR_F(end->in); GL @@@ tut nicht ! */
end->in = in;
current_ir_graph = rem;
}
+
+
+/**
+ * Called by walker of remove_critical_cf_edges.
+ *
+ * Place an empty block to an edge between a blocks of multiple
+ * predecessors and a block of multiple sucessors.
+ *
+ * @param n IR node
+ * @param env Envirnment of walker. This field is unused and has
+ * the value NULL.
+ */
+static void walk_critical_cf_edges(ir_node *n, void *env) {
+ int arity, i;
+ ir_node *pre, *block, **in, *jmp;
+
+ /* Block has multiple predecessors */
+ if ((op_Block == get_irn_op(n)) &&
+ (get_irn_arity(n) > 1)) {
+ arity = get_irn_arity(n);
+
+ for (i=0; i<arity; i++) {
+ pre = get_irn_n(n, i);
+ /* Predecessor has multiple sucessors. Insert new flow edge */
+ if ((NULL != pre) && (op_Proj == get_irn_op(pre))) {
+
+ /* set predeseccor array for new block */
+ in = NEW_ARR_D (ir_node *, current_ir_graph->obst, 1);
+ /* set predecessor of new block */
+ in[0] = pre;
+ block = new_Block(1, in);
+ /* insert new jmp node to new block */
+ switch_block(block);
+ jmp = new_Jmp();
+ switch_block(n);
+ /* set sucessor of new block */
+ set_irn_n(n, i, jmp);
+
+ } /* predecessor has multiple sucessors */
+ } /* for all predecessors */
+ } /* n is a block */
+}
+
+void remove_critical_cf_edges(ir_graph *irg) {
+ if (get_opt_critical_edges())
+ irg_walk_graph(irg, NULL, walk_critical_cf_edges, NULL);
+}
projects / libfirm / blobdiff