[RFA][PATCH] Provide a class interface into substitute_and_fold.
Jeff Law
law@redhat.com
Tue Oct 24 18:57:00 GMT 2017
This is similar to the introduction of the ssa_propagate_engine, but for
the substitution/replacements bits.
In a couple places the pass specific virtual functions are just wrappers
around existing functions. A good example of this is
ccp_folder::get_value. Many other routines in tree-ssa-ccp.c want to
use get_constant_value. Some may be convertable to use the class
instance, but I haven't looked closely.
Another example is vrp_folder::get_value. In this case we're wrapping
op_with_constant_singleton_value. In a later patch that moves into the
to-be-introduced vr_values class so we'll delegate to that class rather
than wrap.
FWIW I did look at having a single class for the propagation engine and
the substitution engine. That turned out to be a bit problematical due
to the calls into the substitution engine from the evrp bits which don't
use the propagation engine at all. Given propagation and substitution
are distinct concepts I ultimately decided the cleanest path forward was
to keep the two classes separate.
Bootstrapped and regression tested on x86_64. OK for the trunk?
Jeff
-------------- next part --------------
* tree-ssa-ccp.c (ccp_folder): New class derived from
substitute_and_fold_engine.
(ccp_folder::get_value): New member function.
(ccp_folder::fold_stmt): Renamed from ccp_fold_stmt.
(ccp_fold_stmt): Remove prototype.
(ccp_finalize): Call substitute_and_fold from the ccp_class.
* tree-ssa-copy.c (copy_folder): New class derived from
substitute_and_fold_engine.
(copy_folder::get_value): Renamed from get_value.
(fini_copy_prop): Call substitute_and_fold from copy_folder class.
* tree-vrp.c (vrp_folder): New class derived from
substitute_and_fold_engine.
(vrp_folder::fold_stmt): Renamed from vrp_fold_stmt.
(vrp_folder::get_value): New member function.
(vrp_finalize): Call substitute_and_fold from vrp_folder class.
(evrp_dom_walker::before_dom_children): Similarly for replace_uses_in.
* tree-ssa-propagate.h (substitute_and_fold_engine): New class to
provide a class interface to folder/substitute routines.
(ssa_prop_fold_stmt_fn): Remove typedef.
(ssa_prop_get_value_fn): Likewise.
(subsitute_and_fold): Remove prototype.
(replace_uses_in): Likewise.
* tree-ssa-propagate.c (substitute_and_fold_engine::replace_uses_in):
Renamed from replace_uses_in. Call the virtual member function
(substitute_and_fold_engine::replace_phi_args_in): Similarly.
(substitute_and_fold_dom_walker): Remove initialization of
data member entries for calbacks. Add substitute_and_fold_engine
member and initialize it.
(substitute_and_fold_dom_walker::before_dom_children0: Use the
member functions for get_value, replace_phi_args_in c
replace_uses_in, and fold_stmt calls.
(substitute_and_fold_engine::substitute_and_fold): Renamed from
substitute_and_fold. Remove assert. Update ctor call.
diff --git a/gcc/tree-ssa-ccp.c b/gcc/tree-ssa-ccp.c
index fec562e..da06172 100644
--- a/gcc/tree-ssa-ccp.c
+++ b/gcc/tree-ssa-ccp.c
@@ -188,7 +188,6 @@ static ccp_prop_value_t *const_val;
static unsigned n_const_val;
static void canonicalize_value (ccp_prop_value_t *);
-static bool ccp_fold_stmt (gimple_stmt_iterator *);
static void ccp_lattice_meet (ccp_prop_value_t *, ccp_prop_value_t *);
/* Dump constant propagation value VAL to file OUTF prefixed by PREFIX. */
@@ -909,6 +908,24 @@ do_dbg_cnt (void)
}
+/* We want to provide our own GET_VALUE and FOLD_STMT virtual methods. */
+class ccp_folder : public substitute_and_fold_engine
+{
+ public:
+ tree get_value (tree);
+ bool fold_stmt (gimple_stmt_iterator *);
+};
+
+/* This method just wraps GET_CONSTANT_VALUE for now. Over time
+ naked calls to GET_CONSTANT_VALUE should be eliminated in favor
+ of calling member functions. */
+
+tree
+ccp_folder::get_value (tree op)
+{
+ return get_constant_value (op);
+}
+
/* Do final substitution of propagated values, cleanup the flowgraph and
free allocated storage. If NONZERO_P, record nonzero bits.
@@ -967,7 +984,8 @@ ccp_finalize (bool nonzero_p)
}
/* Perform substitutions based on the known constant values. */
- something_changed = substitute_and_fold (get_constant_value, ccp_fold_stmt);
+ class ccp_folder ccp_folder;
+ something_changed = ccp_folder.substitute_and_fold ();
free (const_val);
const_val = NULL;
@@ -2176,8 +2194,8 @@ fold_builtin_alloca_with_align (gimple *stmt)
/* Fold the stmt at *GSI with CCP specific information that propagating
and regular folding does not catch. */
-static bool
-ccp_fold_stmt (gimple_stmt_iterator *gsi)
+bool
+ccp_folder::fold_stmt (gimple_stmt_iterator *gsi)
{
gimple *stmt = gsi_stmt (*gsi);
diff --git a/gcc/tree-ssa-copy.c b/gcc/tree-ssa-copy.c
index a57535c..e45d188 100644
--- a/gcc/tree-ssa-copy.c
+++ b/gcc/tree-ssa-copy.c
@@ -489,10 +489,16 @@ init_copy_prop (void)
}
}
+class copy_folder : public substitute_and_fold_engine
+{
+ public:
+ tree get_value (tree);
+};
+
/* Callback for substitute_and_fold to get at the final copy-of values. */
-static tree
-get_value (tree name)
+tree
+copy_folder::get_value (tree name)
{
tree val;
if (SSA_NAME_VERSION (name) >= n_copy_of)
@@ -557,7 +563,8 @@ fini_copy_prop (void)
}
}
- bool changed = substitute_and_fold (get_value, NULL);
+ class copy_folder copy_folder;
+ bool changed = copy_folder.substitute_and_fold ();
if (changed)
{
free_numbers_of_iterations_estimates (cfun);
diff --git a/gcc/tree-ssa-propagate.c b/gcc/tree-ssa-propagate.c
index 90df285..62955be 100644
--- a/gcc/tree-ssa-propagate.c
+++ b/gcc/tree-ssa-propagate.c
@@ -853,7 +853,7 @@ static struct prop_stats_d prop_stats;
PROP_VALUE. Return true if at least one reference was replaced. */
bool
-replace_uses_in (gimple *stmt, ssa_prop_get_value_fn get_value)
+substitute_and_fold_engine::replace_uses_in (gimple *stmt)
{
bool replaced = false;
use_operand_p use;
@@ -862,7 +862,7 @@ replace_uses_in (gimple *stmt, ssa_prop_get_value_fn get_value)
FOR_EACH_SSA_USE_OPERAND (use, stmt, iter, SSA_OP_USE)
{
tree tuse = USE_FROM_PTR (use);
- tree val = (*get_value) (tuse);
+ tree val = get_value (tuse);
if (val == tuse || val == NULL_TREE)
continue;
@@ -891,8 +891,8 @@ replace_uses_in (gimple *stmt, ssa_prop_get_value_fn get_value)
/* Replace propagated values into all the arguments for PHI using the
values from PROP_VALUE. */
-static bool
-replace_phi_args_in (gphi *phi, ssa_prop_get_value_fn get_value)
+bool
+substitute_and_fold_engine::replace_phi_args_in (gphi *phi)
{
size_t i;
bool replaced = false;
@@ -909,7 +909,7 @@ replace_phi_args_in (gphi *phi, ssa_prop_get_value_fn get_value)
if (TREE_CODE (arg) == SSA_NAME)
{
- tree val = (*get_value) (arg);
+ tree val = get_value (arg);
if (val && val != arg && may_propagate_copy (arg, val))
{
@@ -960,10 +960,10 @@ class substitute_and_fold_dom_walker : public dom_walker
{
public:
substitute_and_fold_dom_walker (cdi_direction direction,
- ssa_prop_get_value_fn get_value_fn_,
- ssa_prop_fold_stmt_fn fold_fn_)
- : dom_walker (direction), get_value_fn (get_value_fn_),
- fold_fn (fold_fn_), something_changed (false)
+ class substitute_and_fold_engine *engine)
+ : dom_walker (direction),
+ something_changed (false),
+ substitute_and_fold_engine (engine)
{
stmts_to_remove.create (0);
stmts_to_fixup.create (0);
@@ -979,12 +979,12 @@ public:
virtual edge before_dom_children (basic_block);
virtual void after_dom_children (basic_block) {}
- ssa_prop_get_value_fn get_value_fn;
- ssa_prop_fold_stmt_fn fold_fn;
bool something_changed;
vec<gimple *> stmts_to_remove;
vec<gimple *> stmts_to_fixup;
bitmap need_eh_cleanup;
+
+ class substitute_and_fold_engine *substitute_and_fold_engine;
};
edge
@@ -1001,7 +1001,7 @@ substitute_and_fold_dom_walker::before_dom_children (basic_block bb)
continue;
if (res && TREE_CODE (res) == SSA_NAME)
{
- tree sprime = get_value_fn (res);
+ tree sprime = substitute_and_fold_engine->get_value (res);
if (sprime
&& sprime != res
&& may_propagate_copy (res, sprime))
@@ -1010,7 +1010,7 @@ substitute_and_fold_dom_walker::before_dom_children (basic_block bb)
continue;
}
}
- something_changed |= replace_phi_args_in (phi, get_value_fn);
+ something_changed |= substitute_and_fold_engine->replace_phi_args_in (phi);
}
/* Propagate known values into stmts. In some case it exposes
@@ -1027,7 +1027,7 @@ substitute_and_fold_dom_walker::before_dom_children (basic_block bb)
tree lhs = gimple_get_lhs (stmt);
if (lhs && TREE_CODE (lhs) == SSA_NAME)
{
- tree sprime = get_value_fn (lhs);
+ tree sprime = substitute_and_fold_engine->get_value (lhs);
if (sprime
&& sprime != lhs
&& may_propagate_copy (lhs, sprime)
@@ -1056,7 +1056,7 @@ substitute_and_fold_dom_walker::before_dom_children (basic_block bb)
&& gimple_call_noreturn_p (stmt));
/* Replace real uses in the statement. */
- did_replace |= replace_uses_in (stmt, get_value_fn);
+ did_replace |= substitute_and_fold_engine->replace_uses_in (stmt);
/* If we made a replacement, fold the statement. */
if (did_replace)
@@ -1069,16 +1069,13 @@ substitute_and_fold_dom_walker::before_dom_children (basic_block bb)
/* Some statements may be simplified using propagator
specific information. Do this before propagating
into the stmt to not disturb pass specific information. */
- if (fold_fn)
+ update_stmt_if_modified (stmt);
+ if (substitute_and_fold_engine->fold_stmt(&i))
{
- update_stmt_if_modified (stmt);
- if ((*fold_fn)(&i))
- {
- did_replace = true;
- prop_stats.num_stmts_folded++;
- stmt = gsi_stmt (i);
- gimple_set_modified (stmt, true);
- }
+ did_replace = true;
+ prop_stats.num_stmts_folded++;
+ stmt = gsi_stmt (i);
+ gimple_set_modified (stmt, true);
}
/* If this is a control statement the propagator left edges
@@ -1164,19 +1161,15 @@ substitute_and_fold_dom_walker::before_dom_children (basic_block bb)
Return TRUE when something changed. */
bool
-substitute_and_fold (ssa_prop_get_value_fn get_value_fn,
- ssa_prop_fold_stmt_fn fold_fn)
+substitute_and_fold_engine::substitute_and_fold (void)
{
- gcc_assert (get_value_fn);
-
if (dump_file && (dump_flags & TDF_DETAILS))
fprintf (dump_file, "\nSubstituting values and folding statements\n\n");
memset (&prop_stats, 0, sizeof (prop_stats));
calculate_dominance_info (CDI_DOMINATORS);
- substitute_and_fold_dom_walker walker(CDI_DOMINATORS,
- get_value_fn, fold_fn);
+ substitute_and_fold_dom_walker walker (CDI_DOMINATORS, this);
walker.walk (ENTRY_BLOCK_PTR_FOR_FN (cfun));
/* We cannot remove stmts during the BB walk, especially not release
diff --git a/gcc/tree-ssa-propagate.h b/gcc/tree-ssa-propagate.h
index cff9e53..629ae77 100644
--- a/gcc/tree-ssa-propagate.h
+++ b/gcc/tree-ssa-propagate.h
@@ -61,17 +61,11 @@ enum ssa_prop_result {
};
-/* Call-back functions used by the value propagation engine. */
-typedef bool (*ssa_prop_fold_stmt_fn) (gimple_stmt_iterator *gsi);
-typedef tree (*ssa_prop_get_value_fn) (tree);
-
-
extern bool valid_gimple_rhs_p (tree);
extern void move_ssa_defining_stmt_for_defs (gimple *, gimple *);
extern bool update_gimple_call (gimple_stmt_iterator *, tree, int, ...);
extern bool update_call_from_tree (gimple_stmt_iterator *, tree);
extern bool stmt_makes_single_store (gimple *);
-extern bool substitute_and_fold (ssa_prop_get_value_fn, ssa_prop_fold_stmt_fn);
extern bool may_propagate_copy (tree, tree);
extern bool may_propagate_copy_into_stmt (gimple *, tree);
extern bool may_propagate_copy_into_asm (tree);
@@ -79,7 +73,6 @@ extern void propagate_value (use_operand_p, tree);
extern void replace_exp (use_operand_p, tree);
extern void propagate_tree_value (tree *, tree);
extern void propagate_tree_value_into_stmt (gimple_stmt_iterator *, tree);
-extern bool replace_uses_in (gimple *stmt, ssa_prop_get_value_fn get_value);
/* Public interface into the SSA propagation engine. Clients should inherit
from this class and provide their own visitors. */
@@ -104,4 +97,14 @@ class ssa_propagation_engine
};
+class substitute_and_fold_engine
+{
+ public:
+ bool substitute_and_fold (void);
+ bool replace_uses_in (gimple *);
+ virtual bool fold_stmt (gimple_stmt_iterator *) { return false; }
+ virtual tree get_value (tree) { return NULL_TREE; }
+ bool replace_phi_args_in (gphi *);
+};
+
#endif /* _TREE_SSA_PROPAGATE_H */
diff --git a/gcc/tree-vrp.c b/gcc/tree-vrp.c
index e8fce3e..ea8ceee 100644
--- a/gcc/tree-vrp.c
+++ b/gcc/tree-vrp.c
@@ -10536,10 +10536,17 @@ fold_predicate_in (gimple_stmt_iterator *si)
return false;
}
+class vrp_folder : public substitute_and_fold_engine
+{
+ public:
+ tree get_value (tree);
+ bool fold_stmt (gimple_stmt_iterator *);
+};
+
/* Callback for substitute_and_fold folding the stmt at *SI. */
-static bool
-vrp_fold_stmt (gimple_stmt_iterator *si)
+bool
+vrp_folder::fold_stmt (gimple_stmt_iterator *si)
{
if (fold_predicate_in (si))
return true;
@@ -10547,6 +10554,18 @@ vrp_fold_stmt (gimple_stmt_iterator *si)
return simplify_stmt_using_ranges (si);
}
+/* If OP has a value range with a single constant value return that,
+ otherwise return NULL_TREE. This returns OP itself if OP is a
+ constant.
+
+ Implemented as a pure wrapper right now, but this will change. */
+
+tree
+vrp_folder::get_value (tree op)
+{
+ return op_with_constant_singleton_value_range (op);
+}
+
/* Return the LHS of any ASSERT_EXPR where OP appears as the first
argument to the ASSERT_EXPR and in which the ASSERT_EXPR dominates
BB. If no such ASSERT_EXPR is found, return OP. */
@@ -10888,7 +10907,8 @@ vrp_finalize (bool warn_array_bounds_p)
wi::to_wide (vr_value[i]->max));
}
- substitute_and_fold (op_with_constant_singleton_value_range, vrp_fold_stmt);
+ class vrp_folder vrp_folder;
+ vrp_folder.substitute_and_fold ();
if (warn_array_bounds && warn_array_bounds_p)
check_all_array_refs ();
@@ -11225,8 +11245,8 @@ evrp_dom_walker::before_dom_children (basic_block bb)
}
/* Try folding stmts with the VR discovered. */
- bool did_replace
- = replace_uses_in (stmt, op_with_constant_singleton_value_range);
+ class vrp_folder vrp_folder;
+ bool did_replace = vrp_folder.replace_uses_in (stmt);
if (fold_stmt (&gsi, follow_single_use_edges)
|| did_replace)
{
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