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Commit e74e0c8f authored by Michael Beck's avatar Michael Beck
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- uses new SSA constructor interface, shortening and clering the code 

- bugfix: really set current_ir_graph
- return non-zero if replacements were found

[r19161]
parent 1f915eb7
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Inline Side-by-side
include/libfirm/iroptimize.h
View file @ e74e0c8f
......@@ -417,8 +417,10 @@ void normalize_n_returns(ir_graph *irg);
* with atomic values if possible. Does not handle classes yet.
*
* @param irg the graph which should be optimized
*
* @return non-zero, if at least one entity was replaced
*/
void scalar_replacement_opt(ir_graph *irg);
int scalar_replacement_opt(ir_graph *irg);
/** Performs strength reduction for the passed graph. */
void reduce_strength(ir_graph *irg);
......
ir/opt/scalar_replace.c
View file @ e74e0c8f
......@@ -243,12 +243,13 @@ int is_address_taken(ir_node *sel)
*
* @param ent the entity that will be scalar replaced
* @param sel a Sel node that selects some fields of this entity
*
* Uses the visited flag to mark already linked Sel nodes.
*/
static void link_all_leave_sels(ir_entity *ent, ir_node *sel) {
int i, n, flag = 1;
int i, flag = 1;
n = get_irn_n_outs(sel);
for (i = 0; i < n; ++i) {
for (i = get_irn_n_outs(sel) - 1; i >= 0; --i) {
ir_node *succ = get_irn_out(sel, i);
if (is_Sel(succ)) {
......@@ -295,28 +296,21 @@ static void *ADDRESS_TAKEN = &_x;
* potentially
*/
static int find_possible_replacements(ir_graph *irg) {
ir_node *irg_frame = get_irg_frame(irg);
int i, n;
int res = 0;
ir_node *irg_frame;
ir_type *frame_tp;
int i;
int res = 0;
set_using_irn_visited(irg);
inc_irg_visited(irg);
n = get_irn_n_outs(irg_frame);
/*
* First, clear the link field of all interesting entities.
* Note that we did not rely on the fact that there is only
* one Sel node per entity, so we might access one entity
* more than once here.
* That's why we have need two loops.
*/
for (i = 0; i < n; ++i) {
ir_node *succ = get_irn_out(irg_frame, i);
if (is_Sel(succ)) {
ir_entity *ent = get_Sel_entity(succ);
set_entity_link(ent, NULL);
}
frame_tp = get_irg_frame_type(irg);
for (i = get_class_n_members(frame_tp) - 1; i >= 0; --i) {
ir_entity *ent = get_class_member(frame_tp, i);
set_entity_link(ent, NULL);
}
/*
......@@ -324,7 +318,8 @@ static int find_possible_replacements(ir_graph *irg) {
* isn't a scalar replacement set the link of this entity
* equal ADDRESS_TAKEN.
*/
for (i = 0; i < n; ++i) {
irg_frame = get_irg_frame(irg);
for (i = get_irn_n_outs(irg_frame) - 1; i >= 0; --i) {
ir_node *succ = get_irn_out(irg_frame, i);
if (is_Sel(succ)) {
......@@ -363,6 +358,7 @@ static int find_possible_replacements(ir_graph *irg) {
}
}
clear_using_irn_visited(irg);
return res;
}
......@@ -419,6 +415,7 @@ static unsigned allocate_value_numbers(pset *sels, ir_entity *ent, unsigned vnum
path_t *key, *path;
set *pathes = new_set(path_cmp, 8);
DB((dbg, SET_LEVEL_3, " Visiting Sel nodes of entity %+F\n", ent));
/* visit all Sel nodes in the chain of the entity */
for (sel = get_entity_link(ent); sel; sel = next) {
next = get_irn_link(sel);
......@@ -429,14 +426,17 @@ static unsigned allocate_value_numbers(pset *sels, ir_entity *ent, unsigned vnum
key = find_path(sel, 0);
path = set_find(pathes, key, PATH_SIZE(key), path_hash(key));
if (path)
if (path) {
SET_VNUM(sel, path->vnum);
else {
DB((dbg, SET_LEVEL_3, " %+F represents value %u\n", sel, path->vnum));
} else {
key->vnum = vnum++;
set_insert(pathes, key, PATH_SIZE(key), path_hash(key));
SET_VNUM(sel, key->vnum);
DB((dbg, SET_LEVEL_3, " %+F represents value %u\n", sel, key->vnum));
ARR_EXTO(ir_mode *, *modes, (int)((key->vnum + 15) & ~15));
(*modes)[key->vnum] = get_type_mode(get_entity_type(get_Sel_entity(sel)));
......@@ -478,95 +478,89 @@ typedef struct _list_entry_t {
* environment for memory walker
*/
typedef struct _env_t {
struct obstack obst; /**< a obstack for the value blocks */
int nvals; /**< number of values */
ir_mode **modes; /**< the modes of the values */
list_entry_t *fix_phis; /**< list of all Phi nodes that must be fixed */
list_entry_t *fix_loads; /**< list of all Load nodes that must be fixed */
pset *sels; /**< A set of all Sel nodes that have a value number */
} env_t;
/**
* topological walker.
* topological post-walker.
*/
static void topologic_walker(ir_node *node, void *ctx) {
env_t *env = ctx;
ir_op *op = get_irn_op(node);
ir_node *adr, *block, *mem, *unk, **value_arr, **in, *val;
ir_node *adr, *block, *mem, *val;
ir_mode *mode;
unsigned vnum;
int i, j, n;
list_entry_t *l;
if (op == op_Load) {
/* a load, check if we can resolve it */
adr = get_Load_ptr(node);
if (! is_Sel(adr))
DB((dbg, SET_LEVEL_3, " checking %+F for replacement ", node));
if (! is_Sel(adr)) {
DB((dbg, SET_LEVEL_3, "no Sel input (%+F)\n", adr));
return;
}
if (! pset_find_ptr(env->sels, adr))
if (! pset_find_ptr(env->sels, adr)) {
DB((dbg, SET_LEVEL_3, "Sel %+F has no VNUM\n", adr));
return;
}
/* ok, we have a Load that will be replaced */
vnum = GET_VNUM(adr);
assert(vnum < (unsigned)env->nvals);
block = get_nodes_block(node);
value_arr = get_irn_link(block);
DB((dbg, SET_LEVEL_3, "replacing by value %u\n", vnum));
/* check, if we can replace this Load */
if (value_arr[vnum]) {
mem = get_Load_mem(node);
/* Beware: A Load can contain a hidden conversion in Firm.
This happens for instance in the following code:
int i;
unsigned j = *(unsigned *)&i;
Handle this here. */
val = value_arr[vnum];
mode = get_Load_mode(node);
if (mode != get_irn_mode(val))
val = new_d_Conv(get_irn_dbg_info(node), val, mode);
turn_into_tuple(node, pn_Load_max);
set_Tuple_pred(node, pn_Load_M, mem);
set_Tuple_pred(node, pn_Load_res, val);
set_Tuple_pred(node, pn_Load_X_regular, new_r_Jmp(current_ir_graph, block));
set_Tuple_pred(node, pn_Load_X_except, new_Bad());
} else {
l = obstack_alloc(&env->obst, sizeof(*l));
l->node = node;
l->vnum = vnum;
val = get_value(vnum, env->modes[vnum]);
set_irn_link(node, env->fix_loads);
env->fix_loads = l;
}
/* Beware: A Load can contain a hidden conversion in Firm.
This happens for instance in the following code:
int i;
unsigned j = *(unsigned *)&i;
Handle this here. */
mode = get_Load_mode(node);
if (mode != get_irn_mode(val))
val = new_d_Conv(get_irn_dbg_info(node), val, mode);
mem = get_Load_mem(node);
block = get_nodes_block(node);
turn_into_tuple(node, pn_Load_max);
set_Tuple_pred(node, pn_Load_M, mem);
set_Tuple_pred(node, pn_Load_res, val);
set_Tuple_pred(node, pn_Load_X_regular, new_r_Jmp(current_ir_graph, block));
set_Tuple_pred(node, pn_Load_X_except, new_Bad());
} else if (op == op_Store) {
DB((dbg, SET_LEVEL_3, " checking %+F for replacement ", node));
/* a Store always can be replaced */
adr = get_Store_ptr(node);
if (! is_Sel(adr))
if (! is_Sel(adr)) {
DB((dbg, SET_LEVEL_3, "no Sel input (%+F)\n", adr));
return;
}
if (! pset_find_ptr(env->sels, adr))
if (! pset_find_ptr(env->sels, adr)) {
DB((dbg, SET_LEVEL_3, "Sel %+F has no VNUM\n", adr));
return;
}
vnum = GET_VNUM(adr);
assert(vnum < (unsigned)env->nvals);
block = get_nodes_block(node);
value_arr = get_irn_link(block);
DB((dbg, SET_LEVEL_3, "replacing by value %u\n", vnum));
/* Beware: A Store can contain a hidden conversion in Firm. */
val = get_Store_value(node);
if (get_irn_mode(val) != env->modes[vnum])
val = new_d_Conv(get_irn_dbg_info(node), val, env->modes[vnum]);
value_arr[vnum] = val;
set_value(vnum, val);
mem = get_Store_mem(node);
block = get_nodes_block(node);
......@@ -575,146 +569,11 @@ static void topologic_walker(ir_node *node, void *ctx) {
set_Tuple_pred(node, pn_Store_M, mem);
set_Tuple_pred(node, pn_Store_X_regular, new_r_Jmp(current_ir_graph, block));
set_Tuple_pred(node, pn_Store_X_except, new_Bad());
} else if (op == op_Phi && get_irn_mode(node) == mode_M) {
/*
* found a memory Phi: Here, we must create new Phi nodes
*/
block = get_nodes_block(node);
value_arr = get_irn_link(block);
n = get_Block_n_cfgpreds(block);
in = alloca(sizeof(*in) * n);
for (i = env->nvals - 1; i >= 0; --i) {
unk = new_Unknown(env->modes[i]);
for (j = n - 1; j >= 0; --j)
in[j] = unk;
value_arr[i] = new_r_Phi(current_ir_graph, block, n, in, env->modes[i]);
l = obstack_alloc(&env->obst, sizeof(*l));
l->node = value_arr[i];
l->vnum = i;
set_irn_link(value_arr[i], env->fix_phis);
env->fix_phis = l;
}
}
}
/**
* Walker: allocate the value array for every block.
*/
static void alloc_value_arr(ir_node *block, void *ctx) {
env_t *env = ctx;
ir_node **var_arr = obstack_alloc(&env->obst, sizeof(*var_arr) * env->nvals);
/* the value array is empty at start */
memset(var_arr, 0, sizeof(*var_arr) * env->nvals);
set_irn_link(block, var_arr);
}
/**
* searches through blocks beginning from block for value
* vnum and return it.
*/
static ir_node *find_vnum_value(ir_node *block, unsigned vnum) {
ir_node **value_arr;
int i;
ir_node *res;
if (Block_not_block_visited(block)) {
mark_Block_block_visited(block);
value_arr = get_irn_link(block);
if (value_arr[vnum])
return value_arr[vnum];
for (i = get_Block_n_cfgpreds(block) - 1; i >= 0; --i) {
ir_node *pred = get_Block_cfgpred(block, i);
res = find_vnum_value(get_nodes_block(pred), vnum);
if (res)
return res;
}
}
return NULL;
}
/**
* fix the Phi list
*/
static void fix_phis(env_t *env) {
list_entry_t *l;
ir_node *phi, *block, *pred, *val;
int i;
for (l = env->fix_phis; l; l = get_irn_link(phi)) {
phi = l->node;
block = get_nodes_block(phi);
for (i = get_irn_arity(phi) - 1; i >= 0; --i) {
pred = get_Block_cfgpred(block, i);
pred = get_nodes_block(pred);
inc_irg_block_visited(current_ir_graph);
val = find_vnum_value(pred, l->vnum);
if (val)
set_irn_n(phi, i, val);
}
}
}
/**
* fix the Load list
*/
static void fix_loads(env_t *env) {
list_entry_t *l;
ir_node *load, *block, *pred, *val = NULL, *mem;
ir_mode *mode;
int i;
for (l = env->fix_loads; l; l = get_irn_link(load)) {
load = l->node;
block = get_nodes_block(load);
for (i = get_Block_n_cfgpreds(block) - 1; i >= 0; --i) {
pred = get_Block_cfgpred(block, i);
pred = get_nodes_block(pred);
inc_irg_block_visited(current_ir_graph);
val = find_vnum_value(pred, l->vnum);
if (val)
break;
}
if (! val) {
/* access of an uninitialized value */
val = new_Unknown(env->modes[l->vnum]);
}
/* Beware: A Load can contain a hidden conversion in Firm.
Handle this here. */
mode = get_Load_mode(load);
if (mode != get_irn_mode(val))
val = new_d_Conv(get_irn_dbg_info(load), val, mode);
mem = get_Load_mem(load);
turn_into_tuple(load, pn_Load_max);
set_Tuple_pred(load, pn_Load_M, mem);
set_Tuple_pred(load, pn_Load_res, val);
set_Tuple_pred(load, pn_Load_X_regular, new_r_Jmp(current_ir_graph, block));
set_Tuple_pred(load, pn_Load_X_except, new_Bad());
}
}
/**
* Make scalar replacement.
* Make scalar replacement.
*
* @param sels A set containing all Sel nodes that have a value number
* @param nvals The number of scalars.
......@@ -724,27 +583,20 @@ static void fix_loads(env_t *env) {
static void do_scalar_replacements(pset *sels, int nvals, ir_mode **modes) {
env_t env;
obstack_init(&env.obst);
ssa_cons_start(current_ir_graph, nvals);
env.nvals = nvals;
env.modes = modes;
env.fix_phis = NULL;
env.fix_loads = NULL;
env.sels = sels;
/* first step: allocate the value arrays for every block */
irg_block_walk_graph(current_ir_graph, NULL, alloc_value_arr, &env);
/*
* second step: walk over the graph blockwise in topological order
* and fill the array as much as possible.
*/
DB((dbg, SET_LEVEL_3, "Substituting Loads and Stores in %+F\n", current_ir_graph));
irg_walk_blkwise_graph(current_ir_graph, NULL, topologic_walker, &env);
/* third, fix the list of Phis, then the list of Loads */
fix_phis(&env);
fix_loads(&env);
obstack_free(&env.obst, NULL);
ssa_cons_finish(current_ir_graph);
}
/*
......@@ -762,11 +614,13 @@ void scalar_replacement_opt(ir_graph *irg) {
pset *sels;
ir_type *ent_type;
ir_graph *rem;
int res = 0;
if (! get_opt_scalar_replacement())
return;
return 0;
rem = current_ir_graph;
current_ir_graph = irg;
/* Call algorithm that computes the out edges */
assure_irg_outs(irg);
......@@ -782,7 +636,7 @@ void scalar_replacement_opt(ir_graph *irg) {
set_ent = new_set(ent_cmp, 8);
sels = pset_new_ptr(8);
for (i = 0 ; i < get_irn_n_outs(irg_frame); i++) {
for (i = get_irn_n_outs(irg_frame) - 1; i >= 0; --i) {
ir_node *succ = get_irn_out(irg_frame, i);
if (is_Sel(succ)) {
......@@ -830,14 +684,16 @@ void scalar_replacement_opt(ir_graph *irg) {
*/
set_irg_outs_inconsistent(irg);
set_irg_loopinfo_inconsistent(irg);
res = 1
}
del_pset(sels);
del_set(set_ent);
DEL_ARR_F(modes);
}
current_ir_graph = rem;
return res;
}
void firm_init_scalar_replace(void) {
......
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