This reduces the depth of the loop tree. */
#define NO_LOOPS_WITHOUT_HEAD 1
-static ir_graph *outermost_ir_graph; /* The outermost graph the scc is computed
- for */
-static ir_loop *current_loop; /* Current loop construction is working
- on. */
-static int loop_node_cnt = 0; /* Counts the number of allocated loop nodes.
- Each loop node gets a unique number.
- What for? ev. remove. @@@ */
-static int current_dfn = 1; /* Counter to generate depth first numbering
- of visited nodes. */
+/** The outermost graph the scc is computed for. */
+static ir_graph *outermost_ir_graph;
+/** Current loop construction is working on. */
+static ir_loop *current_loop;
+/** Counts the number of allocated loop nodes.
+ * Each loop node gets a unique number.
+ * @todo What for? ev. remove.
+ */
+static int loop_node_cnt = 0;
+/** Counter to generate depth first numbering of visited nodes. */
+static int current_dfn = 1;
static int max_loop_depth = 0;
-void link_to_reg_end (ir_node *n, void *env);
+void link_to_reg_end(ir_node *n, void *env);
void set_projx_link(ir_node *cb_projx, ir_node *end_projx);
ir_node *get_projx_link(ir_node *cb_projx);
/**********************************************************************/
typedef struct scc_info {
- int in_stack; /**< Marks whether node is on the stack. */
- int dfn; /**< Depth first search number. */
- int uplink; /**< dfn number of ancestor. */
- /* ir_loop *loop; *//* Refers to the containing loop. */
- /*
- struct section *section;
- xset def;
- xset use;
- */
+ int in_stack; /**< Marks whether node is on the stack. */
+ int dfn; /**< Depth first search number. */
+ int uplink; /**< dfn number of ancestor. */
+ /* ir_loop *loop; *//* Refers to the containing loop. */
+ /*
+ struct section *section;
+ xset def;
+ xset use;
+ */
} scc_info;
-static INLINE scc_info* new_scc_info(void) {
- scc_info *info = obstack_alloc (outermost_ir_graph->obst, sizeof (scc_info));
- memset (info, 0, sizeof (scc_info));
- return info;
+/**
+ * Allocates a new SCC info on the given obstack.
+ */
+static INLINE scc_info *new_scc_info(struct obstack *obst) {
+ scc_info *info = obstack_alloc(obst, sizeof(*info));
+ memset(info, 0, sizeof(*info));
+ return info;
}
-static INLINE void
-mark_irn_in_stack (ir_node *n) {
- scc_info *scc = get_irn_link(n);
- assert(scc);
- scc->in_stack = 1;
+/**
+ * Mark node n being on the SCC stack.
+ */
+static INLINE void mark_irn_in_stack(ir_node *n) {
+ scc_info *scc = get_irn_link(n);
+ assert(scc);
+ scc->in_stack = 1;
}
-static INLINE void
-mark_irn_not_in_stack (ir_node *n) {
- scc_info *scc = get_irn_link(n);
- assert(scc);
- scc->in_stack = 0;
+/**
+* Mark node n NOT being on the SCC stack.
+*/
+static INLINE void mark_irn_not_in_stack(ir_node *n) {
+ scc_info *scc = get_irn_link(n);
+ assert(scc);
+ scc->in_stack = 0;
}
-static INLINE int
-irn_is_in_stack (ir_node *n) {
- scc_info *scc = get_irn_link(n);
- assert(scc);
- return scc->in_stack;
+/**
+ * Checks if a node is on the SCC stack.
+ */
+static INLINE int irn_is_in_stack(ir_node *n) {
+ scc_info *scc = get_irn_link(n);
+ assert(scc);
+ return scc->in_stack;
}
-static INLINE void
-set_irn_uplink (ir_node *n, int uplink) {
- scc_info *scc = get_irn_link(n);
- assert(scc);
- scc->uplink = uplink;
+/**
+ * Sets the uplink number for a node.
+ */
+static INLINE void set_irn_uplink(ir_node *n, int uplink) {
+ scc_info *scc = get_irn_link(n);
+ assert(scc);
+ scc->uplink = uplink;
}
-int
-get_irn_uplink (ir_node *n) {
- scc_info *scc = get_irn_link(n);
- assert(scc);
- return scc->uplink;
+/**
+ * Returns the uplink number for a node.
+ */
+static int get_irn_uplink(ir_node *n) {
+ scc_info *scc = get_irn_link(n);
+ assert(scc);
+ return scc->uplink;
}
-static INLINE void
-set_irn_dfn (ir_node *n, int dfn) {
- scc_info *scc = get_irn_link(n);
- assert(scc);
- scc->dfn = dfn;
+/**
+ * Sets the depth-first-search number for a node.
+ */
+static INLINE void set_irn_dfn(ir_node *n, int dfn) {
+ scc_info *scc = get_irn_link(n);
+ assert(scc);
+ scc->dfn = dfn;
}
-int
-get_irn_dfn (ir_node *n) {
- scc_info *scc = get_irn_link(n);
- assert(scc);
- return scc->dfn;
+/**
+ * Returns the depth-first-search number of a node.
+ */
+static int get_irn_dfn(ir_node *n) {
+ scc_info *scc = get_irn_link(n);
+ assert(scc);
+ return scc->dfn;
}
+#if 0
+static ir_loop *find_nodes_loop(ir_node *n, ir_loop *l) {
+ int i;
+ ir_loop *res = NULL;
-void
-set_irn_loop (ir_node *n, ir_loop *loop) {
- n->loop = loop;
-}
-
-/* Uses temporary information to get the loop */
-ir_loop *(get_irn_loop)(const ir_node *n) {
- return _get_irn_loop(n);
-}
+ /* Test whether n is contained in this loop. */
+ for (i = 0; i < get_loop_n_nodes(l); i++)
+ if (n == get_loop_node(l, i)) return l;
+ /* Is this a leave in the loop tree? If so loop not found. */
+ if (get_loop_n_sons(l) == 0) return NULL;
-#if 0
-static ir_loop *find_nodes_loop (ir_node *n, ir_loop *l) {
- int i;
- ir_loop *res = NULL;
-
- /* Test whether n is contained in this loop. */
- for (i = 0; i < get_loop_n_nodes(l); i++)
- if (n == get_loop_node(l, i)) return l;
-
- /* Is this a leave in the loop tree? If so loop not found. */
- if (get_loop_n_sons(l) == 0) return NULL;
-
- /* Else descend in the loop tree. */
- for (i = 0; i < get_loop_n_sons(l); i++) {
- res = find_nodes_loop(n, get_loop_son(l, i));
- if (res) break;
- }
- return res;
+ /* Else descend in the loop tree. */
+ for (i = 0; i < get_loop_n_sons(l); i++) {
+ res = find_nodes_loop(n, get_loop_son(l, i));
+ if (res) break;
+ }
+ return res;
}
/* @@@ temporary implementation, costly!!! */
ir_loop * get_irn_loop(ir_node *n) {
- ir_loop *l = get_irg_loop(current_ir_graph);
- l = find_nodes_loop(n, l);
- return l;
+ ir_loop *l = get_irg_loop(current_ir_graph);
+ l = find_nodes_loop(n, l);
+ return l;
}
#endif
* initializes the stack
*/
static INLINE void init_stack(void) {
- if (stack) {
- ARR_RESIZE (ir_node *, stack, 1000);
- } else {
- stack = NEW_ARR_F (ir_node *, 1000);
- }
- tos = 0;
+ if (stack) {
+ ARR_RESIZE(ir_node *, stack, 1000);
+ } else {
+ stack = NEW_ARR_F(ir_node *, 1000);
+ }
+ tos = 0;
}
#if 0
+/**
+ * Frees the stack.
+ */
static INLINE void free_stack(void) {
- DEL_ARR_F(stack);
- stack = NULL;
- tos = 0;
+ if (stack != NULL) {
+ DEL_ARR_F(stack);
+ stack = NULL;
+ }
+ tos = 0;
}
#endif
*
* @param n The node to push
*/
-static INLINE void
-push (ir_node *n)
-{
- if (tos == ARR_LEN (stack)) {
- int nlen = ARR_LEN (stack) * 2;
- ARR_RESIZE (ir_node *, stack, nlen);
- }
- stack [tos++] = n;
- mark_irn_in_stack(n);
+static INLINE void push(ir_node *n) {
+ if (tos == ARR_LEN(stack)) {
+ int nlen = ARR_LEN(stack) * 2;
+ ARR_RESIZE(ir_node *, stack, nlen);
+ }
+ stack [tos++] = n;
+ mark_irn_in_stack(n);
}
/**
*
* @return The topmost node
*/
-static INLINE ir_node *
-pop (void)
-{
- ir_node *n = stack[--tos];
- mark_irn_not_in_stack(n);
- return n;
+static INLINE ir_node *pop(void) {
+ ir_node *n = stack[--tos];
+ mark_irn_not_in_stack(n);
+ return n;
}
/**
* The nodes up to n belong to the current loop.
* Removes them from the stack and adds them to the current loop.
*/
-static INLINE void
-pop_scc_to_loop (ir_node *n)
-{
- ir_node *m;
- int i = 0;
-
- do {
- m = pop();
-
- loop_node_cnt++;
- set_irn_dfn(m, loop_node_cnt);
- add_loop_node(current_loop, m);
- set_irn_loop(m, current_loop);
- i++;
-
- /* if (m==n) break;*/
- } while(m != n);
-
- /* i might be bigger than 1 for dead (and that's why bad) loops */
- /* if(i > 1)
- printf("Mehr als eine Iteration!!!!!!!!!!!!!!!!!!!!!!!!!!!!11111\n");
- */
+static INLINE void pop_scc_to_loop(ir_node *n) {
+ ir_node *m;
+ int i = 0;
+
+ do {
+ m = pop();
+
+ loop_node_cnt++;
+ set_irn_dfn(m, loop_node_cnt);
+ add_loop_node(current_loop, m);
+ set_irn_loop(m, current_loop);
+ ++i;
+ } while (m != n);
+
+ /* i might be bigger than 1 for dead (and that's why bad) loops */
+ /* if(i > 1)
+ printf("Mehr als eine Iteration!!!!!!!!!!!!!!!!!!!!!!!!!!!!11111\n");
+ */
}
/* GL ??? my last son is my grandson??? Removes loops with no
ir_nodes in them. Such loops have only another loop as son. (Why
can't they have two loops as sons? Does it never get that far? ) */
-static void close_loop (ir_loop *l)
-{
- int last = get_loop_n_elements(l) - 1;
- loop_element lelement = get_loop_element(l, last);
- ir_loop *last_son = lelement.son;
+static void close_loop(ir_loop *l) {
+ int last = get_loop_n_elements(l) - 1;
+ loop_element lelement = get_loop_element(l, last);
+ ir_loop *last_son = lelement.son;
- if (get_kind(last_son) == k_ir_loop &&
- get_loop_n_elements(last_son) == 1) {
- ir_loop *gson;
+ if (get_kind(last_son) == k_ir_loop &&
+ get_loop_n_elements(last_son) == 1) {
+ ir_loop *gson;
- lelement = get_loop_element(last_son, 0);
- gson = lelement.son;
+ lelement = get_loop_element(last_son, 0);
+ gson = lelement.son;
- if (get_kind(gson) == k_ir_loop) {
- loop_element new_last_son;
+ if (get_kind(gson) == k_ir_loop) {
+ loop_element new_last_son;
- gson->outer_loop = l;
- new_last_son.son = gson;
- l->children[last] = new_last_son;
- }
- }
+ gson->outer_loop = l;
+ new_last_son.son = gson;
+ l->children[last] = new_last_son;
+ }
+ }
- current_loop = l;
+ current_loop = l;
}
/* Removes and unmarks all nodes up to n from the stack.
The nodes must be visited once more to assign them to a scc. */
-static INLINE void
-pop_scc_unmark_visit (ir_node *n)
-{
- ir_node *m = NULL;
-
- while (m != n) {
- m = pop();
- set_irn_visited(m, 0);
- }
+static INLINE void pop_scc_unmark_visit(ir_node *n) {
+ ir_node *m = NULL;
+
+ while (m != n) {
+ m = pop();
+ set_irn_visited(m, 0);
+ }
}
/**********************************************************************/
/* Allocates a new loop as son of current_loop. Sets current_loop
to the new loop and returns the father. */
-ir_loop *new_loop (void) {
- ir_loop *father, *son;
-
- father = current_loop;
-
- son = (ir_loop *) obstack_alloc (outermost_ir_graph->obst, sizeof (ir_loop));
- memset (son, 0, sizeof (ir_loop));
- son->kind = k_ir_loop;
- son->children = NEW_ARR_F (loop_element, 0);
- son->n_nodes = 0;
- son->n_sons=0;
- if (father) {
- son->outer_loop = father;
- add_loop_son(father, son);
- son->depth = father->depth+1;
- if (son->depth > max_loop_depth) max_loop_depth = son->depth;
- } else { /* The root loop */
- son->outer_loop = son;
- son->depth = 0;
- }
-
-#ifdef DEBUG_libfirm
- son->loop_nr = get_irp_new_node_nr();
- son->link = NULL;
-#endif
-
- current_loop = son;
- return father;
-}
-
-#if 0
-/* Finishes the datastructures, copies the arrays to the obstack
- of current_ir_graph.
- A. Schoesser: Caution: loop -> sons is gone. */
-static void mature_loop (ir_loop *loop) {
- ir_loop **new_sons;
-
- new_sons = NEW_ARR_D (ir_loop *, current_ir_graph->obst, ARR_LEN(loop->sons));
- memcpy (new_sons, loop->sons, sizeof (ir_loop *) * ARR_LEN(loop->sons));
- DEL_ARR_F(loop->sons);
- loop->sons = new_sons;
-}
-#endif
-
-/* Returns outer loop, itself if outermost. */
-ir_loop *(get_loop_outer_loop)(const ir_loop *loop) {
- return _get_loop_outer_loop(loop);
-}
-
-/* Returns nesting depth of this loop */
-int (get_loop_depth)(const ir_loop *loop) {
- return _get_loop_depth(loop);
-}
-
-/* Returns the number of inner loops */
-int (get_loop_n_sons)(const ir_loop *loop) {
- return _get_loop_n_sons(loop);
-}
-
-/* Returns the pos`th loop_node-child *
- * TODO: This method isn`t very efficient ! *
- * Returns NULL if there isn`t a pos`th loop_node */
-ir_loop *get_loop_son (ir_loop *loop, int pos) {
- int child_nr = 0, loop_nr = -1;
-
- assert(loop && loop->kind == k_ir_loop);
- while(child_nr < ARR_LEN(loop->children))
- {
- if(*(loop -> children[child_nr].kind) == k_ir_loop)
- loop_nr++;
- if(loop_nr == pos)
- return(loop -> children[child_nr].son);
- child_nr++;
- }
- return NULL;
-}
-
-/* Use EXCLUSIVELY this function to add sons, otherwise the loop->n_sons
- is invalid! */
-
-void
-add_loop_son(ir_loop *loop, ir_loop *son) {
- loop_element lson;
- lson.son = son;
- assert(loop && loop->kind == k_ir_loop);
- assert(get_kind(son) == k_ir_loop);
- ARR_APP1 (loop_element, loop->children, lson);
- loop -> n_sons++;
-}
-
-/* Returns the number of nodes in the loop */
-int get_loop_n_nodes (ir_loop *loop) {
- assert(loop); assert(loop->kind == k_ir_loop);
- return loop -> n_nodes;
-/* return ARR_LEN(loop->nodes); */
-}
-
-/* Returns the pos`th ir_node-child *
- * TODO: This method isn`t very efficient ! *
- * Returns NULL if there isn`t a pos`th ir_node */
-ir_node *get_loop_node (ir_loop *loop, int pos) {
- int child_nr, node_nr = -1;
-
- assert(loop && loop->kind == k_ir_loop);
- assert(pos < get_loop_n_nodes(loop));
-
- for (child_nr = 0; child_nr < ARR_LEN(loop->children); child_nr++) {
- if(*(loop -> children[child_nr].kind) == k_ir_node)
- node_nr++;
- if(node_nr == pos)
- return(loop -> children[child_nr].node);
- }
-
- assert(0 && "no child at pos found");
- return NULL;
-}
-
-/* Use EXCLUSIVELY this function to add nodes, otherwise the loop->n_nodes
- is invalid! */
-
-void
-add_loop_node(ir_loop *loop, ir_node *n) {
- loop_element ln;
- ln.node = n;
- assert(loop && loop->kind == k_ir_loop);
- assert(get_kind(n) == k_ir_node || get_kind(n) == k_ir_graph); /* used in callgraph.c */
- ARR_APP1 (loop_element, loop->children, ln);
- loop->n_nodes++;
-}
+static ir_loop *new_loop(void) {
+ ir_loop *father = current_loop;
+ ir_loop *son = alloc_loop(father, outermost_ir_graph->obst);
-/* Returns the number of elements contained in loop. */
-int get_loop_n_elements (const ir_loop *loop) {
- assert(loop && loop->kind == k_ir_loop);
- return(ARR_LEN(loop->children));
+ if (son->depth > max_loop_depth) max_loop_depth = son->depth;
+ current_loop = son;
+ return father;
}
-/*
- Returns the pos`th loop element.
- This may be a loop_node or a ir_node. The caller of this function has
- to check the *(loop_element.kind) field for "k_ir_node" or "k_ir_loop"
- and then select the appropriate "loop_element.node" or "loop_element.son".
-*/
-
-loop_element get_loop_element(const ir_loop *loop, int pos) {
- assert(loop && loop->kind == k_ir_loop && pos < ARR_LEN(loop->children));
- return(loop -> children[pos]);
-}
-
-int get_loop_element_pos(const ir_loop *loop, void *le) {
- int i, n;
- assert(loop && loop->kind == k_ir_loop);
-
- n = get_loop_n_elements(loop);
- for (i = 0; i < n; i++)
- if (get_loop_element(loop, i).node == le) return i;
- return -1;
-}
-
-int get_loop_loop_nr(const ir_loop *loop) {
- assert(loop && loop->kind == k_ir_loop);
-#ifdef DEBUG_libfirm
- return loop->loop_nr;
-#else
- return (int)loop;
-#endif
-}
-
-
-/** A field to connect additional information to a loop. Only valid
- if libfirm_debug is set. */
-void set_loop_link (ir_loop *loop, void *link) {
- assert(loop && loop->kind == k_ir_loop);
- loop->link = link;
-}
-void *get_loop_link (const ir_loop *loop) {
- assert(loop && loop->kind == k_ir_loop);
- return loop->link;
-}
-
-int (is_ir_loop)(const void *thing) {
- return _is_ir_loop(thing);
-}
-
-/* The outermost loop is remarked in the surrounding graph. */
-void (set_irg_loop)(ir_graph *irg, ir_loop *loop) {
- _set_irg_loop(irg, loop);
-}
-
-/* Returns the root loop info (if exists) for an irg. */
-ir_loop *(get_irg_loop)(ir_graph *irg) {
- return _get_irg_loop(irg);
-}
-
-
/**********************************************************************/
/* Constructing and destructing the loop/backedge information. **/
/**********************************************************************/
/* Initialization steps. **********************************************/
-static INLINE void
-init_node (ir_node *n, void *env) {
- (void) env;
- set_irn_link (n, new_scc_info());
- clear_backedges(n);
+static INLINE void init_node(ir_node *n, void *env) {
+ struct obstack *obst = env;
+ set_irn_link(n, new_scc_info(obst));
+ clear_backedges(n);
}
-static INLINE void
-init_scc_common (void) {
- current_dfn = 1;
- loop_node_cnt = 0;
- init_stack();
+static INLINE void init_scc_common(void) {
+ current_dfn = 1;
+ loop_node_cnt = 0;
+ init_stack();
}
-static INLINE void
-init_scc (ir_graph *irg) {
- init_scc_common();
- irg_walk_graph (irg, init_node, NULL, NULL);
- /*
- irg_walk (irg, link_to_reg_end, NULL, NULL);
- */
+static INLINE void init_scc(ir_graph *irg, struct obstack *obst) {
+ init_scc_common();
+ irg_walk_graph(irg, init_node, NULL, obst);
+ /*
+ irg_walk (irg, link_to_reg_end, NULL, NULL);
+ */
}
#ifdef INTERPROCEDURAL_VIEW
-static INLINE void
-init_ip_scc (void) {
- init_scc_common();
- cg_walk (init_node, NULL, NULL);
+static INLINE void init_ip_scc(struct obstack *obst) {
+ init_scc_common();
+ cg_walk(init_node, NULL, obst);
#if EXPERIMENTAL_LOOP_TREE
- cg_walk (link_to_reg_end, NULL, NULL);
+ cg_walk(link_to_reg_end, NULL, NULL);
#endif
}
#endif
/* Condition for breaking the recursion. */
static int is_outermost_Start(ir_node *n) {
- /* Test whether this is the outermost Start node. If so
- recursion must end. */
- if ((get_irn_op(n) == op_Block) &&
- (get_Block_n_cfgpreds(n) == 1) &&
- (get_irn_op(skip_Proj(get_Block_cfgpred(n, 0))) == op_Start) &&
- (get_nodes_block(skip_Proj(get_Block_cfgpred(n, 0))) == n)) {
- return 1;
- }
+ /* Test whether this is the outermost Start node. If so
+ recursion must end. */
+ if ((get_irn_op(n) == op_Block) &&
+ (get_Block_n_cfgpreds(n) == 1) &&
+ (get_irn_op(skip_Proj(get_Block_cfgpred(n, 0))) == op_Start) &&
+ (get_nodes_block(skip_Proj(get_Block_cfgpred(n, 0))) == n)) {
+ return 1;
+ }
#if 0
- /* @@@ Bad condition:
- not possible in interprocedural view as outermost_graph is
- not necessarily the only with a dead-end start block.
- Besides current_ir_graph is not set properly. */
- if ((get_irn_op(n) == op_Block) &&
- (n == get_irg_start_block(current_ir_graph))) {
- if ((!get_interprocedural_view()) ||
- (current_ir_graph == outermost_ir_graph))
- return 1;
- }
+ /* @@@ Bad condition:
+ not possible in interprocedural view as outermost_graph is
+ not necessarily the only with a dead-end start block.
+ Besides current_ir_graph is not set properly. */
+ if ((get_irn_op(n) == op_Block) &&
+ (n == get_irg_start_block(current_ir_graph))) {
+ if ((!get_interprocedural_view()) ||
+ (current_ir_graph == outermost_ir_graph))
+ return 1;
+ }
#endif
- return 0;
+ return 0;
}
/* When to walk from nodes to blocks. Only for Control flow operations? */
-static INLINE int
-get_start_index(ir_node *n) {
+static INLINE int get_start_index(ir_node *n) {
#undef BLOCK_BEFORE_NODE
#define BLOCK_BEFORE_NODE 1
#if BLOCK_BEFORE_NODE
- /* This version assures, that all nodes are ordered absolutely. This allows
- to undef all nodes in the heap analysis if the block is false, which means
- not reachable.
- I.e., with this code, the order on the loop tree is correct. But a (single)
- test showed the loop tree is deeper. */
- if (get_irn_op(n) == op_Phi ||
- get_irn_op(n) == op_Block ||
- (get_irn_op(n) == op_Filter && get_interprocedural_view()) ||
- (get_irg_pinned(get_irn_irg(n)) == op_pin_state_floats &&
- get_irn_pinned(n) == op_pin_state_floats))
- // Here we could test for backedge at -1 which is illegal
- return 0;
- else
- return -1;
+ /* This version assures, that all nodes are ordered absolutely. This allows
+ to undef all nodes in the heap analysis if the block is false, which means
+ not reachable.
+ I.e., with this code, the order on the loop tree is correct. But a (single)
+ test showed the loop tree is deeper. */
+ if (get_irn_op(n) == op_Phi ||
+ get_irn_op(n) == op_Block ||
+ (get_irn_op(n) == op_Filter && get_interprocedural_view()) ||
+ (get_irg_pinned(get_irn_irg(n)) == op_pin_state_floats &&
+ get_irn_pinned(n) == op_pin_state_floats))
+ // Here we could test for backedge at -1 which is illegal
+ return 0;
+ else
+ return -1;
#else
- /* This version causes deeper loop trees (at least we verified this
- for Polymor).
- But it guarantees that Blocks are analysed before nodes contained in the
- block. If so, we can set the value to undef if the block is not \
- executed. */
- if (is_cfop(n) || is_fragile_op(n) || get_irn_op(n) == op_Start)
- return -1;
- else
- return 0;
+ /* This version causes deeper loop trees (at least we verified this
+ for Polymor).
+ But it guarantees that Blocks are analysed before nodes contained in the
+ block. If so, we can set the value to undef if the block is not \
+ executed. */
+ if (is_cfop(n) || is_fragile_op(n) || get_irn_op(n) == op_Start)
+ return -1;
+ else
+ return 0;
#endif
}
/* Test for legal loop header: Block, Phi, ... */
static INLINE int is_possible_loop_head(ir_node *n) {
- ir_op *op = get_irn_op(n);
- return ((op == op_Block) ||
- (op == op_Phi) ||
- ((op == op_Filter) && get_interprocedural_view()));
+ ir_op *op = get_irn_op(n);
+ return ((op == op_Block) ||
+ (op == op_Phi) ||
+ ((op == op_Filter) && get_interprocedural_view()));
}
-/* Returns non-zero if n is a loop header, i.e., it is a Block, Phi
- or Filter node and has predecessors within the loop and out
- of the loop.
- @arg root: only needed for assertion. */
-static int
-is_head (ir_node *n, ir_node *root)
-{
- int i, arity;
- int some_outof_loop = 0, some_in_loop = 0;
-
- /* Test for legal loop header: Block, Phi, ... */
- if (!is_possible_loop_head(n))
- return 0;
-
- if (!is_outermost_Start(n)) {
- arity = get_irn_arity(n);
- for (i = get_start_index(n); i < arity; i++) {
- ir_node *pred = get_irn_n(n, i);
- assert(pred);
- if (is_backedge(n, i)) continue;
- if (!irn_is_in_stack(pred)) {
- some_outof_loop = 1;
- } else {
- if(get_irn_uplink(pred) < get_irn_uplink(root)) {
- assert(get_irn_uplink(pred) >= get_irn_uplink(root));
- }
- some_in_loop = 1;
- }
- }
- }
- return some_outof_loop && some_in_loop;
+/**
+ * Returns non-zero if n is a loop header, i.e., it is a Block, Phi
+ * or Filter node and has predecessors within the loop and out
+ * of the loop.
+ * @param root: only needed for assertion.
+ */
+static int is_head(ir_node *n, ir_node *root) {
+ int i, arity;
+ int some_outof_loop = 0, some_in_loop = 0;
+
+ /* Test for legal loop header: Block, Phi, ... */
+ if (!is_possible_loop_head(n))
+ return 0;
+
+ if (!is_outermost_Start(n)) {
+ arity = get_irn_arity(n);
+ for (i = get_start_index(n); i < arity; i++) {
+ ir_node *pred = get_irn_n(n, i);
+ assert(pred);
+ if (is_backedge(n, i))
+ continue;
+ if (!irn_is_in_stack(pred)) {
+ some_outof_loop = 1;
+ } else {
+ if (get_irn_uplink(pred) < get_irn_uplink(root)) {
+ assert(get_irn_uplink(pred) >= get_irn_uplink(root));
+ }
+ some_in_loop = 1;
+ }
+ }
+ }
+ return some_outof_loop && some_in_loop;
}
/**
* within the loop.
* @param root: only needed for assertion.
*/
-static int
-is_endless_head (ir_node *n, ir_node *root)
-{
- int i, arity;
- int some_outof_loop = 0, some_in_loop = 0;
-
- /* Test for legal loop header: Block, Phi, ... */
- if (!is_possible_loop_head(n))
- return 0;
-
- if (!is_outermost_Start(n)) {
- arity = get_irn_arity(n);
- for (i = get_start_index(n); i < arity; i++) {
- ir_node *pred = get_irn_n(n, i);
- assert(pred);
- if (is_backedge(n, i)) { continue; }
- if (!irn_is_in_stack(pred)) {
- some_outof_loop = 1; //printf(" some out of loop ");
- } else {
- if(get_irn_uplink(pred) < get_irn_uplink(root)) {
- assert(get_irn_uplink(pred) >= get_irn_uplink(root));
- }
- some_in_loop = 1;
- }
- }
- }
- return !some_outof_loop && some_in_loop;
-}
-
-/* Returns index of the predecessor with the smallest dfn number
- greater-equal than limit. */
-static int
-smallest_dfn_pred (ir_node *n, int limit)
-{
- int i, index = -2, min = -1;
-
- if (!is_outermost_Start(n)) {
- int arity = get_irn_arity(n);
- for (i = get_start_index(n); i < arity; i++) {
- ir_node *pred = get_irn_n(n, i);
- assert(pred);
- if (is_backedge(n, i) || !irn_is_in_stack(pred)) continue;
- if (get_irn_dfn(pred) >= limit && (min == -1 || get_irn_dfn(pred) < min)) {
- index = i;
- min = get_irn_dfn(pred);
- }
- }
- }
- return index;
+static int is_endless_head(ir_node *n, ir_node *root) {
+ int i, arity;
+ int some_outof_loop = 0, some_in_loop = 0;
+
+ /* Test for legal loop header: Block, Phi, ... */
+ if (!is_possible_loop_head(n))
+ return 0;
+
+ if (!is_outermost_Start(n)) {
+ arity = get_irn_arity(n);
+ for (i = get_start_index(n); i < arity; i++) {
+ ir_node *pred = get_irn_n(n, i);
+ assert(pred);
+ if (is_backedge(n, i)) { continue; }
+ if (!irn_is_in_stack(pred)) {
+ some_outof_loop = 1; //printf(" some out of loop ");
+ } else {
+ if (get_irn_uplink(pred) < get_irn_uplink(root)) {
+ assert(get_irn_uplink(pred) >= get_irn_uplink(root));
+ }
+ some_in_loop = 1;
+ }
+ }
+ }
+ return !some_outof_loop && some_in_loop;
+}
+
+/** Returns index of the predecessor with the smallest dfn number
+ greater-equal than limit. */
+static int smallest_dfn_pred(ir_node *n, int limit) {
+ int i, index = -2, min = -1;
+
+ if (!is_outermost_Start(n)) {
+ int arity = get_irn_arity(n);
+ for (i = get_start_index(n); i < arity; i++) {
+ ir_node *pred = get_irn_n(n, i);
+ assert(pred);
+ if (is_backedge(n, i) || !irn_is_in_stack(pred)) continue;
+ if (get_irn_dfn(pred) >= limit && (min == -1 || get_irn_dfn(pred) < min)) {
+ index = i;
+ min = get_irn_dfn(pred);
+ }
+ }
+ }
+ return index;
}
/* Returns index of the predecessor with the largest dfn number. */
-static int
-largest_dfn_pred (ir_node *n)
-{
- int i, index = -2, max = -1;
-
- if (!is_outermost_Start(n)) {
- int arity = get_irn_arity(n);
- for (i = get_start_index(n); i < arity; i++) {
- ir_node *pred = get_irn_n(n, i);
- if (is_backedge (n, i) || !irn_is_in_stack(pred)) continue;
- if (get_irn_dfn(pred) > max) {
- index = i;
- max = get_irn_dfn(pred);
- }
- }
- }
- return index;
+static int largest_dfn_pred(ir_node *n) {
+ int i, index = -2, max = -1;
+
+ if (!is_outermost_Start(n)) {
+ int arity = get_irn_arity(n);
+ for (i = get_start_index(n); i < arity; i++) {
+ ir_node *pred = get_irn_n(n, i);
+ if (is_backedge (n, i) || !irn_is_in_stack(pred)) continue;
+ if (get_irn_dfn(pred) > max) {
+ index = i;
+ max = get_irn_dfn(pred);
+ }
+ }
+ }
+ return index;
}
-/** Searches the stack for possible loop heads. Tests these for backedges.
- If it finds a head with an unmarked backedge it marks this edge and
- returns the tail of the loop.
- If it finds no backedge returns NULL.
- ("disable_backedge" in fiasco)
-*
-* @param n A node where uplink == dfn.
-**/
-
-static ir_node *
-find_tail (ir_node *n) {
- ir_node *m;
- int i, res_index = -2;
-
- /*
- if (!icfg && rm_cyclic_phis && remove_cyclic_phis (n)) return NULL;
- */
- m = stack[tos-1]; /* tos = top of stack */
- if (is_head (m, n)) {
- res_index = smallest_dfn_pred(m, 0);
- if ((res_index == -2) && /* no smallest dfn pred found. */
- (n == m))
- return NULL;
- } else {
- if (m == n) return NULL; // Is this to catch Phi - self loops?
- for (i = tos-2; i >= 0; --i) {
- m = stack[i];
-
- if (is_head (m, n)) {
- res_index = smallest_dfn_pred (m, get_irn_dfn(m) + 1);
- if (res_index == -2) /* no smallest dfn pred found. */
- res_index = largest_dfn_pred (m);
-
- if ((m == n) && (res_index == -2)) { /* dont walk past loop head. */
- i = -1;
- }
- break;
- }
-
- /* We should not walk past our selves on the stack: The upcoming nodes
- are not in this loop. We assume a loop not reachable from Start. */
- if (m == n) {
- i = -1;
- break;
- }
-
- }
-
- if (i < 0) {
- /* A dead loop not reachable from Start. */
- for (i = tos-2; i >= 0; --i) {
- m = stack[i];
- if (is_endless_head (m, n)) {
- res_index = smallest_dfn_pred (m, get_irn_dfn(m) + 1);
- if (res_index == -2) /* no smallest dfn pred found. */
- res_index = largest_dfn_pred (m);
- break;
- }
- if (m == n) { break; } /* It's not an unreachable loop, either. */
- }
- //assert(0 && "no head found on stack");
- }
-
- }
- if (res_index <= -2) {
- /* It's a completely bad loop: without Phi/Block nodes that can
- be a head. I.e., the code is "dying". We break the loop by
- setting Bad nodes. */
- int arity = get_irn_arity(n);
- for (i = -1; i < arity; ++i) {
- set_irn_n(n, i, get_irg_bad(get_irn_irg(n)));
- }
- return NULL;
- }
- assert (res_index > -2);
-
- set_backedge (m, res_index);
- return is_outermost_Start(n) ? NULL : get_irn_n(m, res_index);
+/**
+ * Searches the stack for possible loop heads. Tests these for backedges.
+ * If it finds a head with an unmarked backedge it marks this edge and
+ * returns the tail of the loop.
+ * If it finds no backedge returns NULL.
+ * ("disable_backedge" in fiasco)
+ *
+ * @param n A node where uplink == dfn.
+ */
+static ir_node *find_tail(ir_node *n) {
+ ir_node *m;
+ int i, res_index = -2;
+
+ /*
+ if (!icfg && rm_cyclic_phis && remove_cyclic_phis (n)) return NULL;
+ */
+ m = stack[tos-1]; /* tos = top of stack */
+ if (is_head (m, n)) {
+ res_index = smallest_dfn_pred(m, 0);
+ if ((res_index == -2) && /* no smallest dfn pred found. */
+ (n == m))
+ return NULL;
+ } else {
+ if (m == n) return NULL; // Is this to catch Phi - self loops?
+ for (i = tos-2; i >= 0; --i) {
+ m = stack[i];
+
+ if (is_head (m, n)) {
+ res_index = smallest_dfn_pred (m, get_irn_dfn(m) + 1);
+ if (res_index == -2) /* no smallest dfn pred found. */
+ res_index = largest_dfn_pred (m);
+
+ if ((m == n) && (res_index == -2)) { /* don't walk past loop head. */
+ i = -1;
+ }
+ break;
+ }
+
+ /* We should not walk past our selves on the stack: The upcoming nodes
+ are not in this loop. We assume a loop not reachable from Start. */
+ if (m == n) {
+ i = -1;
+ break;
+ }
+
+ }
+
+ if (i < 0) {
+ /* A dead loop not reachable from Start. */
+ for (i = tos-2; i >= 0; --i) {
+ m = stack[i];
+ if (is_endless_head (m, n)) {
+ res_index = smallest_dfn_pred (m, get_irn_dfn(m) + 1);
+ if (res_index == -2) /* no smallest dfn pred found. */
+ res_index = largest_dfn_pred (m);
+ break;
+ }
+ if (m == n) { break; } /* It's not an unreachable loop, either. */
+ }
+ //assert(0 && "no head found on stack");
+ }
+
+ }
+ if (res_index <= -2) {
+ /* It's a completely bad loop: without Phi/Block nodes that can
+ be a head. I.e., the code is "dying". We break the loop by
+ setting Bad nodes. */
+ int arity = get_irn_arity(n);
+ for (i = -1; i < arity; ++i) {
+ set_irn_n(n, i, get_irg_bad(get_irn_irg(n)));
+ }
+ return NULL;
+ }
+ assert (res_index > -2);
+
+ set_backedge(m, res_index);
+ return is_outermost_Start(n) ? NULL : get_irn_n(m, res_index);
}
on the stack.
- -------------------------------------------------------------- */
-int search_endproj_in_stack(ir_node *start_block)
-{
- int i, j;
- assert(is_Block(start_block));
- for(i = tos - 1; i >= 0; --i)
- {
- if(get_irn_op(stack[i]) == op_Proj && get_irn_mode(stack[i]) == mode_X &&
- get_irn_op(get_irn_n(stack[i], 0)) == op_EndReg)
- {
- printf("FOUND PROJ!!!!!!!!!!!!!!!!!!!!!!!!!!\n");
- ir_node *end_projx = stack[i];
-
- int arity = get_irn_arity(start_block);
- for(j = 0; j < arity; j++)
- {
- ir_node *begin_projx = get_Block_cfgpred(get_irg_start_block(get_irn_irg(end_projx)),
- get_Proj_proj(end_projx));
- if(get_irn_n(start_block, j) == begin_projx)
- {
- printf("FOUND IT!!!!!!!!!!!!!!!!!!\n");
- return(j);
- }
- }
- }
- }
- return(-1);
+int search_endproj_in_stack(ir_node *start_block) {
+ int i, j;
+ assert(is_Block(start_block));
+ for(i = tos - 1; i >= 0; --i)
+ {
+ if(get_irn_op(stack[i]) == op_Proj && get_irn_mode(stack[i]) == mode_X &&
+ get_irn_op(get_irn_n(stack[i], 0)) == op_EndReg)
+ {
+ printf("FOUND PROJ!!!!!!!!!!!!!!!!!!!!!!!!!!\n");
+ ir_node *end_projx = stack[i];
+
+ int arity = get_irn_arity(start_block);
+ for(j = 0; j < arity; j++)
+ {
+ ir_node *begin_projx = get_Block_cfgpred(get_irg_start_block(get_irn_irg(end_projx)),
+ get_Proj_proj(end_projx));
+ if(get_irn_n(start_block, j) == begin_projx)
+ {
+ printf("FOUND IT!!!!!!!!!!!!!!!!!!\n");
+ return(j);
+ }
+ }
+ }
+ }
+ return(-1);
}
static pmap *projx_link = NULL;
void link_to_reg_end (ir_node *n, void *env) {
- if(get_irn_op(n) == op_Proj &&
- get_irn_mode(n) == mode_X &&
- get_irn_op(get_irn_n(n, 0)) == op_EndReg) {
- /* Reg End Projx -> Find the CallBegin Projx and hash it */
- ir_node *end_projx = n;
- ir_node *begin_projx = get_Block_cfgpred(get_irg_start_block(get_irn_irg(end_projx)),
- get_Proj_proj(end_projx));
- set_projx_link(begin_projx, end_projx);
- }
+ if(get_irn_op(n) == op_Proj &&
+ get_irn_mode(n) == mode_X &&
+ get_irn_op(get_irn_n(n, 0)) == op_EndReg) {
+ /* Reg End Projx -> Find the CallBegin Projx and hash it */
+ ir_node *end_projx = n;
+ ir_node *begin_projx = get_Block_cfgpred(get_irg_start_block(get_irn_irg(end_projx)),
+ get_Proj_proj(end_projx));
+ set_projx_link(begin_projx, end_projx);
+ }
}
-void set_projx_link(ir_node *cb_projx, ir_node *end_projx)
-{
- if(projx_link == NULL)
- projx_link = pmap_create();
- pmap_insert(projx_link, (void *)cb_projx, (void *)end_projx);
+void set_projx_link(ir_node *cb_projx, ir_node *end_projx) {
+ if(projx_link == NULL)
+ projx_link = pmap_create();
+ pmap_insert(projx_link, (void *)cb_projx, (void *)end_projx);
}
-ir_node *get_projx_link(ir_node *cb_projx)
-{
- return((ir_node *) pmap_get(projx_link, (void *)cb_projx));
+ir_node *get_projx_link(ir_node *cb_projx) {
+ return((ir_node *) pmap_get(projx_link, (void *)cb_projx));
}
#endif
-static INLINE int
-is_outermost_loop(ir_loop *l) {
- return l == get_loop_outer_loop(l);
+static INLINE int is_outermost_loop(ir_loop *l) {
+ return l == get_loop_outer_loop(l);
}
* The core algorithm. *
*-----------------------------------------------------------*/
-static void scc (ir_node *n) {
- int i;
- if (irn_visited(n)) return;
- mark_irn_visited(n);
-
- /* Initialize the node */
- set_irn_dfn(n, current_dfn); /* Depth first number for this node */
- set_irn_uplink(n, current_dfn); /* ... is default uplink. */
- set_irn_loop(n, NULL);
- current_dfn ++;
- push(n);
-
- /* AS: get_start_index might return -1 for Control Flow Nodes, and thus a negative
- array index would be passed to is_backedge(). But CFG Nodes dont't have a backedge array,
- so is_backedge does not access array[-1] but correctly returns false! */
-
- if (!is_outermost_Start(n)) {
- int arity = get_irn_arity(n);
-
- for (i = get_start_index(n); i < arity; i++) {
- ir_node *m;
- if (is_backedge(n, i)) continue;
- m = get_irn_n(n, i); /* get_irn_ip_pred(n, i); */
- /* if ((!m) || (get_irn_op(m) == op_Unknown)) continue; */
- scc (m);
- if (irn_is_in_stack(m)) {
- /* Uplink of m is smaller if n->m is a backedge.
- Propagate the uplink to mark the loop. */
- if (get_irn_uplink(m) < get_irn_uplink(n))
- set_irn_uplink(n, get_irn_uplink(m));
- }
- }
- }
-
- if (get_irn_dfn(n) == get_irn_uplink(n)) {
- /* This condition holds for
- 1) the node with the incoming backedge.
- That is: We found a loop!
- 2) Straight line code, because no uplink has been propagated, so the
- uplink still is the same as the dfn.
-
- But n might not be a proper loop head for the analysis. Proper loop
- heads are Block and Phi nodes. find_tail searches the stack for
- Block's and Phi's and takes those nodes as loop heads for the current
- loop instead and marks the incoming edge as backedge. */
-
- ir_node *tail = find_tail(n);
- if (tail) {
- /* We have a loop, that is no straight line code,
- because we found a loop head!
- Next actions: Open a new loop on the loop tree and
- try to find inner loops */
+static void scc(ir_node *n) {
+ int i;
+ if (irn_visited(n)) return;
+ mark_irn_visited(n);
+
+ /* Initialize the node */
+ set_irn_dfn(n, current_dfn); /* Depth first number for this node */
+ set_irn_uplink(n, current_dfn); /* ... is default uplink. */
+ set_irn_loop(n, NULL);
+ current_dfn ++;
+ push(n);
+
+ /* AS: get_start_index might return -1 for Control Flow Nodes, and thus a negative
+ array index would be passed to is_backedge(). But CFG Nodes dont't have a backedge array,
+ so is_backedge does not access array[-1] but correctly returns false! */
+
+ if (!is_outermost_Start(n)) {
+ int arity = get_irn_arity(n);
+
+ for (i = get_start_index(n); i < arity; i++) {
+ ir_node *m;
+ if (is_backedge(n, i)) continue;
+ m = get_irn_n(n, i); /* get_irn_ip_pred(n, i); */
+ /* if ((!m) || (get_irn_op(m) == op_Unknown)) continue; */
+ scc(m);
+ if (irn_is_in_stack(m)) {
+ /* Uplink of m is smaller if n->m is a backedge.
+ Propagate the uplink to mark the loop. */
+ if (get_irn_uplink(m) < get_irn_uplink(n))
+ set_irn_uplink(n, get_irn_uplink(m));
+ }
+ }
+ }
+
+ if (get_irn_dfn(n) == get_irn_uplink(n)) {
+ /* This condition holds for
+ 1) the node with the incoming backedge.
+ That is: We found a loop!
+ 2) Straight line code, because no uplink has been propagated, so the
+ uplink still is the same as the dfn.
+
+ But n might not be a proper loop head for the analysis. Proper loop
+ heads are Block and Phi nodes. find_tail searches the stack for
+ Block's and Phi's and takes those nodes as loop heads for the current
+ loop instead and marks the incoming edge as backedge. */
+
+ ir_node *tail = find_tail(n);
+ if (tail) {
+ /* We have a loop, that is no straight line code,
+ because we found a loop head!
+ Next actions: Open a new loop on the loop tree and
+ try to find inner loops */
#if NO_LOOPS_WITHOUT_HEAD
- /* This is an adaption of the algorithm from fiasco / optscc to
- * avoid loops without Block or Phi as first node. This should
- * severely reduce the number of evaluations of nodes to detect
- * a fixpoint in the heap analysis.
- * Further it avoids loops without firm nodes that cause errors
- * in the heap analyses.
- * But attention: don't do it for the outermost loop: This loop
- * is not iterated. A first block can be a loop head in case of
- * an endless recursion. */
-
- ir_loop *l;
- int close;
- if ((get_loop_n_elements(current_loop) > 0) || (is_outermost_loop(current_loop))) {
- l = new_loop();
- close = 1;
- } else {
- l = current_loop;
- close = 0;
- }
+ /* This is an adaption of the algorithm from fiasco / optscc to
+ * avoid loops without Block or Phi as first node. This should
+ * severely reduce the number of evaluations of nodes to detect
+ * a fixpoint in the heap analysis.
+ * Further it avoids loops without firm nodes that cause errors
+ * in the heap analyses.
+ * But attention: don't do it for the outermost loop: This loop
+ * is not iterated. A first block can be a loop head in case of
+ * an endless recursion. */
+
+ ir_loop *l;
+ int close;
+ if ((get_loop_n_elements(current_loop) > 0) || (is_outermost_loop(current_loop))) {
+ l = new_loop();
+ close = 1;
+ } else {
+ l = current_loop;
+ close = 0;
+ }
#else
- ir_loop *l = new_loop();
+ ir_loop *l = new_loop();
#endif
- /* Remove the loop from the stack ... */
- pop_scc_unmark_visit (n);
+ /* Remove the loop from the stack ... */
+ pop_scc_unmark_visit(n);
- /* The current backedge has been marked, that is temporarily eliminated,
- by find tail. Start the scc algorithm
- anew on the subgraph that is left (the current loop without the backedge)
- in order to find more inner loops. */
- scc (tail);
+ /* The current backedge has been marked, that is temporarily eliminated,
+ by find tail. Start the scc algorithm
+ anew on the subgraph that is left (the current loop without the backedge)
+ in order to find more inner loops. */
+ scc(tail);
- assert (irn_visited(n));
+ assert(irn_visited(n));
#if NO_LOOPS_WITHOUT_HEAD
- if (close)
+ if (close)
#endif
- close_loop(l);
- }
- else
- {
- /* No loop head was found, that is we have straightline code.
- Pop all nodes from the stack to the current loop. */
- pop_scc_to_loop(n);
- }
- }
-}
-
-static void my_scc (ir_node *n) {
- int i;
- if (irn_visited(n)) return;
- mark_irn_visited(n);
-
- /* Initialize the node */
- set_irn_dfn(n, current_dfn); /* Depth first number for this node */
- set_irn_uplink(n, current_dfn); /* ... is default uplink. */
- set_irn_loop(n, NULL);
- current_dfn ++;
- push(n);
-
- /* AS: get_start_index might return -1 for Control Flow Nodes, and thus a negative
- array index would be passed to is_backedge(). But CFG Nodes dont't have a backedge array,
- so is_backedge does not access array[-1] but correctly returns false! */
-
- if (!is_outermost_Start(n)) {
- int arity = get_irn_arity(n);
-
- for (i = get_start_index(n); i < arity; i++) {
- ir_node *m;
- if (is_backedge(n, i)) continue;
- m = get_irn_n(n, i); /* get_irn_ip_pred(n, i); */
- /* if ((!m) || (get_irn_op(m) == op_Unknown)) continue; */
- my_scc (m);
- if (irn_is_in_stack(m)) {
- /* Uplink of m is smaller if n->m is a backedge.
- Propagate the uplink to mark the loop. */
- if (get_irn_uplink(m) < get_irn_uplink(n))
- set_irn_uplink(n, get_irn_uplink(m));
- }
- }
- }
-
- if (get_irn_dfn(n) == get_irn_uplink(n)) {
- /* This condition holds for
- 1) the node with the incoming backedge.
- That is: We found a loop!
- 2) Straight line code, because no uplink has been propagated, so the
- uplink still is the same as the dfn.
-
- But n might not be a proper loop head for the analysis. Proper loop
- heads are Block and Phi nodes. find_tail searches the stack for
- Block's and Phi's and takes those nodes as loop heads for the current
- loop instead and marks the incoming edge as backedge. */
-
- ir_node *tail = find_tail(n);
- if (tail) {
- /* We have a loop, that is no straight line code,
- because we found a loop head!
- Next actions: Open a new loop on the loop tree and
- try to find inner loops */
+ close_loop(l);
+ } else {
+ /* No loop head was found, that is we have straight line code.
+ Pop all nodes from the stack to the current loop. */
+ pop_scc_to_loop(n);
+ }
+ }
+}
+
+static void my_scc(ir_node *n) {
+ int i;
+ if (irn_visited(n))
+ return;
+ mark_irn_visited(n);
+
+ /* Initialize the node */
+ set_irn_dfn(n, current_dfn); /* Depth first number for this node */
+ set_irn_uplink(n, current_dfn); /* ... is default uplink. */
+ set_irn_loop(n, NULL);
+ current_dfn ++;
+ push(n);
+
+ /* AS: get_start_index might return -1 for Control Flow Nodes, and thus a negative
+ array index would be passed to is_backedge(). But CFG Nodes dont't have a backedge array,
+ so is_backedge does not access array[-1] but correctly returns false! */
+
+ if (!is_outermost_Start(n)) {
+ int arity = get_irn_arity(n);
+
+ for (i = get_start_index(n); i < arity; i++) {
+ ir_node *m;
+ if (is_backedge(n, i)) continue;
+ m = get_irn_n(n, i); /* get_irn_ip_pred(n, i); */
+ /* if ((!m) || (get_irn_op(m) == op_Unknown)) continue; */
+ my_scc(m);
+ if (irn_is_in_stack(m)) {
+ /* Uplink of m is smaller if n->m is a backedge.
+ Propagate the uplink to mark the loop. */
+ if (get_irn_uplink(m) < get_irn_uplink(n))
+ set_irn_uplink(n, get_irn_uplink(m));
+ }
+ }
+ }
+
+ if (get_irn_dfn(n) == get_irn_uplink(n)) {
+ /* This condition holds for
+ 1) the node with the incoming backedge.
+ That is: We found a loop!
+ 2) Straight line code, because no uplink has been propagated, so the
+ uplink still is the same as the dfn.
+
+ But n might not be a proper loop head for the analysis. Proper loop
+ heads are Block and Phi nodes. find_tail searches the stack for
+ Block's and Phi's and takes those nodes as loop heads for the current
+ loop instead and marks the incoming edge as backedge. */
+
+ ir_node *tail = find_tail(n);
+ if (tail) {
+ /* We have a loop, that is no straight line code,
+ because we found a loop head!
+ Next actions: Open a new loop on the loop tree and
+ try to find inner loops */
#if NO_LOOPS_WITHOUT_HEAD
- /* This is an adaption of the algorithm from fiasco / optscc to
- * avoid loops without Block or Phi as first node. This should
- * severely reduce the number of evaluations of nodes to detect
- * a fixpoint in the heap analysis.
- * Further it avoids loops without firm nodes that cause errors
- * in the heap analyses. */
-
- ir_loop *l;
- int close;
- if ((get_loop_n_elements(current_loop) > 0) || (is_outermost_loop(current_loop))) {
- l = new_loop();
- close = 1;
- } else {
- l = current_loop;
- close = 0;
- }
+ /* This is an adaption of the algorithm from fiasco / optscc to
+ * avoid loops without Block or Phi as first node. This should
+ * severely reduce the number of evaluations of nodes to detect
+ * a fixpoint in the heap analysis.
+ * Further it avoids loops without firm nodes that cause errors
+ * in the heap analyses. */
+
+ ir_loop *l;
+ int close;
+ if ((get_loop_n_elements(current_loop) > 0) || (is_outermost_loop(current_loop))) {
+ l = new_loop();
+ close = 1;
+ } else {
+ l = current_loop;
+ close = 0;
+ }
#else
- ir_loop *l = new_loop();
+ ir_loop *l = new_loop();
#endif
- /* Remove the loop from the stack ... */
- pop_scc_unmark_visit (n);
+ /* Remove the loop from the stack ... */
+ pop_scc_unmark_visit(n);
- /* The current backedge has been marked, that is temporarily eliminated,
- by find tail. Start the scc algorithm
- anew on the subgraph that is left (the current loop without the backedge)
- in order to find more inner loops. */
- my_scc (tail);
+ /* The current backedge has been marked, that is temporarily eliminated,
+ by find tail. Start the scc algorithm
+ anew on the subgraph that is left (the current loop without the backedge)
+ in order to find more inner loops. */
+ my_scc(tail);
- assert (irn_visited(n));
+ assert(irn_visited(n));
#if NO_LOOPS_WITHOUT_HEAD
- if (close)
+ if (close)
#endif
- close_loop(l);
- }
- else
- {
- /* No loop head was found, that is we have straightline code.
- Pop all nodes from the stack to the current loop. */
- pop_scc_to_loop(n);
- }
- }
+ close_loop(l);
+ } else {
+ /* No loop head was found, that is we have straightline code.
+ Pop all nodes from the stack to the current loop. */
+ pop_scc_to_loop(n);
+ }
+ }
}
/* Constructs backedge information for irg. In interprocedural view constructs
backedges for all methods called by irg, too. */
int construct_backedges(ir_graph *irg) {
- ir_graph *rem = current_ir_graph;
- ir_loop *head_rem;
-
- assert(!get_interprocedural_view() &&
- "not implemented, use construct_ip_backedges");
-
- max_loop_depth = 0;
- current_ir_graph = irg;
- outermost_ir_graph = irg;
-
- init_scc(current_ir_graph);
-
- current_loop = NULL;
- new_loop(); /* sets current_loop */
- head_rem = current_loop; /* Just for assertion */
-
- inc_irg_visited(current_ir_graph);
-
- scc(get_irg_end(current_ir_graph));
-
- assert(head_rem == current_loop);
- set_irg_loop(current_ir_graph, current_loop);
- set_irg_loopinfo_state(current_ir_graph, loopinfo_consistent);
- assert(get_irg_loop(current_ir_graph)->kind == k_ir_loop);
- /*
- irg->loops = current_loop;
- if (icfg == 1) {
- int count = 0;
- int depth = 0;
- count_loop (the_loop, &count, &depth);
- }
- }
- */
- current_ir_graph = rem;
-
- return max_loop_depth;
-}
-
-
-#ifdef INTERPROCEDURAL_VIEW
-int construct_ip_backedges (void) {
- ir_graph *rem = current_ir_graph;
- int rem_ipv = get_interprocedural_view();
- int i;
-
- max_loop_depth = 0;
- assert(get_irp_ip_view_state() == ip_view_valid);
-
- outermost_ir_graph = get_irp_main_irg();
-
- init_ip_scc();
-
- current_loop = NULL;
- new_loop(); /* sets current_loop */
- set_interprocedural_view(1);
-
- inc_max_irg_visited();
- for (i = 0; i < get_irp_n_irgs(); i++)
- set_irg_visited(get_irp_irg(i), get_max_irg_visited());
-
- /** We have to start the walk at the same nodes as cg_walk. **/
- /* Walk starting at unreachable procedures. Only these
- * have End blocks visible in interprocedural view. */
- for (i = 0; i < get_irp_n_irgs(); i++) {
- ir_node *sb;
- current_ir_graph = get_irp_irg(i);
-
- sb = get_irg_start_block(current_ir_graph);
-
- if ((get_Block_n_cfgpreds(sb) > 1) ||
- (get_nodes_block(get_Block_cfgpred(sb, 0)) != sb)) continue;
-
- scc(get_irg_end(current_ir_graph));
- }
-
- /* Check whether we walked all procedures: there could be procedures
- with cyclic calls but no call from the outside. */
- for (i = 0; i < get_irp_n_irgs(); i++) {
- ir_node *sb;
- current_ir_graph = get_irp_irg(i);
-
- /* Test start block: if inner procedure end and end block are not
- * visible and therefore not marked. */
- sb = get_irg_start_block(current_ir_graph);
- if (get_irn_visited(sb) < get_irg_visited(current_ir_graph)) scc(sb);
- }
-
- /* Walk all endless loops in inner procedures.
- * We recognize an inner procedure if the End node is not visited. */
- for (i = 0; i < get_irp_n_irgs(); i++) {
- ir_node *e;
- current_ir_graph = get_irp_irg(i);
-
- e = get_irg_end(current_ir_graph);
- if (get_irn_visited(e) < get_irg_visited(current_ir_graph)) {
- int j;
- /* Don't visit the End node. */
- for (j = 0; j < get_End_n_keepalives(e); j++) scc(get_End_keepalive(e, j));
- }
- }
-
- set_irg_loop(outermost_ir_graph, current_loop);
- set_irg_loopinfo_state(current_ir_graph, loopinfo_ip_consistent);
- assert(get_irg_loop(outermost_ir_graph)->kind == k_ir_loop);
-
- current_ir_graph = rem;
- set_interprocedural_view(rem_ipv);
- return max_loop_depth;
-}
-
-void my_construct_ip_backedges (void) {
- ir_graph *rem = current_ir_graph;
- int rem_ipv = get_interprocedural_view();
- int i;
-
- assert(get_irp_ip_view_state() == ip_view_valid);
+ ir_graph *rem = current_ir_graph;
+ ir_loop *head_rem;
+ struct obstack temp;
- outermost_ir_graph = get_irp_main_irg();
+ assert(!get_interprocedural_view() &&
+ "not implemented, use construct_ip_backedges()");
- init_ip_scc();
+ max_loop_depth = 0;
+ current_ir_graph = irg;
+ outermost_ir_graph = irg;
- current_loop = NULL;
- new_loop(); /* sets current_loop */
- set_interprocedural_view(1);
+ obstack_init(&temp);
+ init_scc(irg, &temp);
- inc_max_irg_visited();
- for (i = 0; i < get_irp_n_irgs(); i++)
- set_irg_visited(get_irp_irg(i), get_max_irg_visited());
+ current_loop = NULL;
+ new_loop(); /* sets current_loop */
+ head_rem = current_loop; /* Just for assertion */
- /** We have to start the walk at the same nodes as cg_walk. **/
- /* Walk starting at unreachable procedures. Only these
- * have End blocks visible in interprocedural view. */
- for (i = 0; i < get_irp_n_irgs(); i++) {
- ir_node *sb;
- current_ir_graph = get_irp_irg(i);
+ inc_irg_visited(irg);
- sb = get_irg_start_block(current_ir_graph);
+ scc(get_irg_end(irg));
- if ((get_Block_n_cfgpreds(sb) > 1) ||
- (get_nodes_block(get_Block_cfgpred(sb, 0)) != sb)) continue;
-
- my_scc(get_irg_end(current_ir_graph));
- }
-
- /* Check whether we walked all procedures: there could be procedures
- with cyclic calls but no call from the outside. */
- for (i = 0; i < get_irp_n_irgs(); i++) {
- ir_node *sb;
- current_ir_graph = get_irp_irg(i);
+ assert(head_rem == current_loop);
+ mature_loops(current_loop, irg->obst);
+ set_irg_loop(irg, current_loop);
+ set_irg_loopinfo_state(irg, loopinfo_consistent);
+ assert(get_irg_loop(irg)->kind == k_ir_loop);
+ /*
+ irg->loops = current_loop;
+ if (icfg == 1) {
+ int count = 0;
+ int depth = 0;
+ count_loop(the_loop, &count, &depth);
+ }
+ */
+ obstack_free(&temp, NULL);
+ current_ir_graph = rem;
+ return max_loop_depth;
+}
- /* Test start block: if inner procedure end and end block are not
- * visible and therefore not marked. */
- sb = get_irg_start_block(current_ir_graph);
- if (get_irn_visited(sb) < get_irg_visited(current_ir_graph)) scc(sb);
- }
- /* Walk all endless loops in inner procedures.
- * We recognize an inner procedure if the End node is not visited. */
- for (i = 0; i < get_irp_n_irgs(); i++) {
- ir_node *e;
- current_ir_graph = get_irp_irg(i);
+#ifdef INTERPROCEDURAL_VIEW
+int construct_ip_backedges(void) {
+ ir_graph *rem = current_ir_graph;
+ int rem_ipv = get_interprocedural_view();
+ int i;
+ strcut obstack temp;
- e = get_irg_end(current_ir_graph);
- if (get_irn_visited(e) < get_irg_visited(current_ir_graph)) {
- int j;
- /* Don't visit the End node. */
- for (j = 0; j < get_End_n_keepalives(e); j++) scc(get_End_keepalive(e, j));
- }
- }
+ max_loop_depth = 0;
+ assert(get_irp_ip_view_state() == ip_view_valid);
- set_irg_loop(outermost_ir_graph, current_loop);
- set_irg_loopinfo_state(current_ir_graph, loopinfo_ip_consistent);
- assert(get_irg_loop(outermost_ir_graph)->kind == k_ir_loop);
+ outermost_ir_graph = get_irp_main_irg();
- current_ir_graph = rem;
- set_interprocedural_view(rem_ipv);
+ obstack_init(&temp);
+ init_ip_scc(&temp);
+
+ current_loop = NULL;
+ new_loop(); /* sets current_loop */
+ set_interprocedural_view(1);
+
+ inc_max_irg_visited();
+ for (i = 0; i < get_irp_n_irgs(); i++)
+ set_irg_visited(get_irp_irg(i), get_max_irg_visited());
+
+ /** We have to start the walk at the same nodes as cg_walk. **/
+ /* Walk starting at unreachable procedures. Only these
+ * have End blocks visible in interprocedural view. */
+ for (i = 0; i < get_irp_n_irgs(); i++) {
+ ir_node *sb;
+ current_ir_graph = get_irp_irg(i);
+
+ sb = get_irg_start_block(current_ir_graph);
+
+ if ((get_Block_n_cfgpreds(sb) > 1) ||
+ (get_nodes_block(get_Block_cfgpred(sb, 0)) != sb))
+ continue;
+
+ scc(get_irg_end(current_ir_graph));
+ }
+
+ /* Check whether we walked all procedures: there could be procedures
+ with cyclic calls but no call from the outside. */
+ for (i = 0; i < get_irp_n_irgs(); i++) {
+ ir_node *sb;
+ current_ir_graph = get_irp_irg(i);
+
+ /* Test start block: if inner procedure end and end block are not
+ * visible and therefore not marked. */
+ sb = get_irg_start_block(current_ir_graph);
+ if (get_irn_visited(sb) < get_irg_visited(current_ir_graph)) scc(sb);
+ }
+
+ /* Walk all endless loops in inner procedures.
+ * We recognize an inner procedure if the End node is not visited. */
+ for (i = 0; i < get_irp_n_irgs(); i++) {
+ ir_node *e;
+ current_ir_graph = get_irp_irg(i);
+
+ e = get_irg_end(current_ir_graph);
+ if (get_irn_visited(e) < get_irg_visited(current_ir_graph)) {
+ int j;
+ /* Don't visit the End node. */
+ for (j = 0; j < get_End_n_keepalives(e); j++)
+ scc(get_End_keepalive(e, j));
+ }
+ }
+
+ set_irg_loop(outermost_ir_graph, current_loop);
+ set_irg_loopinfo_state(current_ir_graph, loopinfo_ip_consistent);
+ assert(get_irg_loop(outermost_ir_graph)->kind == k_ir_loop);
+
+ obstack_free(&temp, NULL);
+ current_ir_graph = rem;
+ set_interprocedural_view(rem_ipv);
+ return max_loop_depth;
+}
+
+void my_construct_ip_backedges(void) {
+ ir_graph *rem = current_ir_graph;
+ int rem_ipv = get_interprocedural_view();
+ int i;
+
+ assert(get_irp_ip_view_state() == ip_view_valid);
+
+ outermost_ir_graph = get_irp_main_irg();
+
+ init_ip_scc();
+
+ current_loop = NULL;
+ new_loop(); /* sets current_loop */
+ set_interprocedural_view(1);
+
+ inc_max_irg_visited();
+ for (i = 0; i < get_irp_n_irgs(); i++)
+ set_irg_visited(get_irp_irg(i), get_max_irg_visited());
+
+ /** We have to start the walk at the same nodes as cg_walk. **/
+ /* Walk starting at unreachable procedures. Only these
+ * have End blocks visible in interprocedural view. */
+ for (i = 0; i < get_irp_n_irgs(); i++) {
+ ir_node *sb;
+ current_ir_graph = get_irp_irg(i);
+
+ sb = get_irg_start_block(current_ir_graph);
+
+ if ((get_Block_n_cfgpreds(sb) > 1) ||
+ (get_nodes_block(get_Block_cfgpred(sb, 0)) != sb)) continue;
+
+ my_scc(get_irg_end(current_ir_graph));
+ }
+
+ /* Check whether we walked all procedures: there could be procedures
+ with cyclic calls but no call from the outside. */
+ for (i = 0; i < get_irp_n_irgs(); i++) {
+ ir_node *sb;
+ current_ir_graph = get_irp_irg(i);
+
+ /* Test start block: if inner procedure end and end block are not
+ * visible and therefore not marked. */
+ sb = get_irg_start_block(current_ir_graph);
+ if (get_irn_visited(sb) < get_irg_visited(current_ir_graph))
+ scc(sb);
+ }
+
+ /* Walk all endless loops in inner procedures.
+ * We recognize an inner procedure if the End node is not visited. */
+ for (i = 0; i < get_irp_n_irgs(); i++) {
+ ir_node *e;
+ current_ir_graph = get_irp_irg(i);
+
+ e = get_irg_end(current_ir_graph);
+ if (get_irn_visited(e) < get_irg_visited(current_ir_graph)) {
+ int j;
+ /* Don't visit the End node. */
+ for (j = 0; j < get_End_n_keepalives(e); j++) scc(get_End_keepalive(e, j));
+ }
+ }
+
+ set_irg_loop(outermost_ir_graph, current_loop);
+ set_irg_loopinfo_state(current_ir_graph, loopinfo_ip_consistent);
+ assert(get_irg_loop(outermost_ir_graph)->kind == k_ir_loop);
+
+ current_ir_graph = rem;
+ set_interprocedural_view(rem_ipv);
}
#endif
static void reset_backedges(ir_node *n) {
- if (is_possible_loop_head(n)) {
+ if (is_possible_loop_head(n)) {
#ifdef INTERPROCEDURAL_VIEW
- int rem = get_interprocedural_view();
+ int rem = get_interprocedural_view();
- set_interprocedural_view(1);
- clear_backedges(n);
- set_interprocedural_view(1);
- clear_backedges(n);
- set_interprocedural_view(rem);
+ set_interprocedural_view(1);
+ clear_backedges(n);
+ set_interprocedural_view(1);
+ clear_backedges(n);
+ set_interprocedural_view(rem);
#else
- clear_backedges(n);
+ clear_backedges(n);
#endif
- }
+ }
}
/*
static void loop_reset_backedges(ir_loop *l) {
- int i;
- reset_backedges(get_loop_node(l, 0));
- for (i = 0; i < get_loop_n_nodes(l); ++i)
- set_irn_loop(get_loop_node(l, i), NULL);
- for (i = 0; i < get_loop_n_sons(l); ++i) {
- loop_reset_backedges(get_loop_son(l, i));
- }
+ int i;
+ reset_backedges(get_loop_node(l, 0));
+ for (i = 0; i < get_loop_n_nodes(l); ++i)
+ set_irn_loop(get_loop_node(l, i), NULL);
+ for (i = 0; i < get_loop_n_sons(l); ++i) {
+ loop_reset_backedges(get_loop_son(l, i));
+ }
}
*/
static void loop_reset_node(ir_node *n, void *env) {
- (void) env;
- set_irn_loop(n, NULL);
- reset_backedges(n);
+ (void) env;
+ set_irn_loop(n, NULL);
+ reset_backedges(n);
}
/** Removes all loop information.
Resets all backedges */
void free_loop_information(ir_graph *irg) {
- /* We can not use this recursion, as the loop might contain
- illegal nodes by now. Why else would we throw away the
- representation?
- if (get_irg_loop(irg)) loop_reset_backedges(get_irg_loop(irg));
- */
- irg_walk_graph(irg, loop_reset_node, NULL, NULL);
- set_irg_loop(irg, NULL);
- set_irg_loopinfo_state(current_ir_graph, loopinfo_none);
- /* We cannot free the loop nodes, they are on the obstack. */
+ /* We can not use this recursion, as the loop might contain
+ illegal nodes by now. Why else would we throw away the
+ representation?
+ if (get_irg_loop(irg)) loop_reset_backedges(get_irg_loop(irg));
+ */
+ irg_walk_graph(irg, loop_reset_node, NULL, NULL);
+ set_irg_loop(irg, NULL);
+ set_irg_loopinfo_state(current_ir_graph, loopinfo_none);
+ /* We cannot free the loop nodes, they are on the obstack. */
}
-void free_all_loop_information (void) {
- int i;
+void free_all_loop_information(void) {
+ int i;
#ifdef INTERPROCEDURAL_VIEW
- int rem = get_interprocedural_view();
- set_interprocedural_view(1); /* To visit all filter nodes */
+ int rem = get_interprocedural_view();
+ set_interprocedural_view(1); /* To visit all filter nodes */
#endif
- for (i = 0; i < get_irp_n_irgs(); i++) {
- free_loop_information(get_irp_irg(i));
- }
+ for (i = 0; i < get_irp_n_irgs(); i++) {
+ free_loop_information(get_irp_irg(i));
+ }
#ifdef INTERPROCEDURAL_VIEW
- set_interprocedural_view(rem);
+ set_interprocedural_view(rem);
#endif
}
/* Debug stuff *************************************************/
static int test_loop_node(ir_loop *l) {
- int i, has_node = 0, found_problem = 0;
- loop_element le;
-
- assert(l && l->kind == k_ir_loop);
-
- if (get_loop_n_elements(l) == 0) {
- found_problem = 1;
- dump_loop(l, "-ha");
- }
-
- le = get_loop_element(l, 0);
- if (*(le.kind) != k_ir_node) {
- assert(le.kind && *(le.kind) == k_ir_loop);
-
- found_problem = 1;
- dump_loop(l, "-ha");
- }
-
- if ((*(le.kind) == k_ir_node) && !is_possible_loop_head(le.node)) {
- found_problem = 1;
- dump_loop(l, "-ha");
- }
-
- if ((get_loop_depth(l) != 0) &&
- (*(le.kind) == k_ir_node) && !has_backedges(le.node)) {
- found_problem = 1;
- dump_loop(l, "-ha");
- }
-
- /* Recur */
- has_node = 0;
- for (i = 0; i < get_loop_n_elements(l); ++i) {
- le = get_loop_element(l, i);
- if (*(le.kind) == k_ir_node)
- has_node++;
- else
- if (test_loop_node(le.son)) found_problem = 1;
- }
-
- if (has_node == 0) {
- found_problem = 1;
- dump_loop(l, "-ha");
- }
-
- return found_problem;
+ int i, has_node = 0, found_problem = 0;
+ loop_element le;
+
+ assert(l && l->kind == k_ir_loop);
+
+ if (get_loop_n_elements(l) == 0) {
+ found_problem = 1;
+ dump_loop(l, "-ha");
+ }
+
+ le = get_loop_element(l, 0);
+ if (*(le.kind) != k_ir_node) {
+ assert(le.kind && *(le.kind) == k_ir_loop);
+
+ found_problem = 1;
+ dump_loop(l, "-ha");
+ }
+
+ if ((*(le.kind) == k_ir_node) && !is_possible_loop_head(le.node)) {
+ found_problem = 1;
+ dump_loop(l, "-ha");
+ }
+
+ if ((get_loop_depth(l) != 0) &&
+ (*(le.kind) == k_ir_node) && !has_backedges(le.node)) {
+ found_problem = 1;
+ dump_loop(l, "-ha");
+ }
+
+ /* Recur */
+ has_node = 0;
+ for (i = 0; i < get_loop_n_elements(l); ++i) {
+ le = get_loop_element(l, i);
+ if (*(le.kind) == k_ir_node)
+ has_node++;
+ else
+ if (test_loop_node(le.son)) found_problem = 1;
+ }
+
+ if (has_node == 0) {
+ found_problem = 1;
+ dump_loop(l, "-ha");
+ }
+
+ return found_problem;
}
/** Prints all loop nodes that
* - the header is not a Phi, Block or Filter.
*/
void find_strange_loop_nodes(ir_loop *l) {
- int found_problem = 0;
- found_problem = test_loop_node(l);
- printf("Finished Test\n\n");
- if (found_problem) exit(0);
+ int found_problem = 0;
+ found_problem = test_loop_node(l);
+ printf("Finished Test\n\n");
+ if (found_problem) exit(0);
}
/* ------------------------------------------------------------------- */
int is_loop_variant(ir_loop *l, ir_loop *b) {
- int i, n_elems;
+ int i, n_elems;
- if (l == b) return 1;
+ if (l == b) return 1;
- n_elems = get_loop_n_elements(l);
- for (i = 0; i < n_elems; ++i) {
- loop_element e = get_loop_element(l, i);
- if (is_ir_loop(e.kind))
- if (is_loop_variant(e.son, b))
- return 1;
- }
+ n_elems = get_loop_n_elements(l);
+ for (i = 0; i < n_elems; ++i) {
+ loop_element e = get_loop_element(l, i);
+ if (is_ir_loop(e.kind))
+ if (is_loop_variant(e.son, b))
+ return 1;
+ }
- return 0;
+ return 0;
}
/* Test whether a value is loop invariant.
* Returns non-zero, if the node n is not changed in the loop block
* belongs to or in inner loops of this blocks loop. */
int is_loop_invariant(ir_node *n, ir_node *block) {
- ir_loop *l = get_irn_loop(block);
- ir_node *b = (is_Block(n)) ? n : get_nodes_block(n);
- return !is_loop_variant(l, get_irn_loop(b));
+ ir_loop *l = get_irn_loop(block);
+ ir_node *b = is_Block(n) ? n : get_nodes_block(n);
+ return !is_loop_variant(l, get_irn_loop(b));
}