/* Conditional constant propagation pass for the GNU compiler.
- Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007
+ Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
Free Software Foundation, Inc.
Adapted from original RTL SSA-CCP by Daniel Berlin <dberlin@dberlin.org>
Adapted to GIMPLE trees by Diego Novillo <dnovillo@redhat.com>
#include "tree-flow.h"
#include "tree-pass.h"
#include "tree-ssa-propagate.h"
+#include "value-prof.h"
#include "langhooks.h"
#include "target.h"
#include "toplev.h"
+#include "dbgcnt.h"
/* Possible lattice values. */
doing the store). */
static prop_value_t *const_val;
-/* True if we are also propagating constants in stores and loads. */
-static bool do_store_ccp;
-
/* Dump constant propagation value VAL to file OUTF prefixed by PREFIX. */
static void
}
-/* The regular is_gimple_min_invariant does a shallow test of the object.
- It assumes that full gimplification has happened, or will happen on the
- object. For a value coming from DECL_INITIAL, this is not true, so we
- have to be more strict ourselves. */
-
-static bool
-ccp_decl_initial_min_invariant (tree t)
-{
- if (!is_gimple_min_invariant (t))
- return false;
- if (TREE_CODE (t) == ADDR_EXPR)
- {
- /* Inline and unroll is_gimple_addressable. */
- while (1)
- {
- t = TREE_OPERAND (t, 0);
- if (is_gimple_id (t))
- return true;
- if (!handled_component_p (t))
- return false;
- }
- }
- return true;
-}
/* If SYM is a constant variable with known value, return the value.
NULL_TREE is returned otherwise. */
-static tree
+tree
get_symbol_constant_value (tree sym)
{
if (TREE_STATIC (sym)
&& !MTAG_P (sym))
{
tree val = DECL_INITIAL (sym);
- if (val
- && ccp_decl_initial_min_invariant (val))
- return val;
+ if (val)
+ {
+ STRIP_USELESS_TYPE_CONVERSION (val);
+ if (is_gimple_min_invariant (val))
+ return val;
+ }
+ /* Variables declared 'const' without an initializer
+ have zero as the initializer if they may not be
+ overridden at link or run time. */
+ if (!val
+ && !DECL_EXTERNAL (sym)
+ && targetm.binds_local_p (sym)
+ && (INTEGRAL_TYPE_P (TREE_TYPE (sym))
+ || SCALAR_FLOAT_TYPE_P (TREE_TYPE (sym))))
+ return fold_convert (TREE_TYPE (sym), integer_zero_node);
}
return NULL_TREE;
change the constant value of the PHI node, which allows for more
constants to be propagated.
- 3- If SSA_NAME_VALUE is set and it is a constant, its value is
- used.
-
- 4- Variables defined by statements other than assignments and PHI
+ 3- Variables defined by statements other than assignments and PHI
nodes are considered VARYING.
- 5- Initial values of variables that are not GIMPLE registers are
+ 4- Initial values of variables that are not GIMPLE registers are
considered VARYING. */
static prop_value_t
get_default_value (tree var)
{
tree sym = SSA_NAME_VAR (var);
- prop_value_t val = { UNINITIALIZED, NULL_TREE, NULL_TREE };
- tree cst_val;
-
- if (!do_store_ccp && !is_gimple_reg (var))
- {
- /* Short circuit for regular CCP. We are not interested in any
- non-register when DO_STORE_CCP is false. */
- val.lattice_val = VARYING;
- }
- else if (SSA_NAME_VALUE (var)
- && is_gimple_min_invariant (SSA_NAME_VALUE (var)))
- {
- val.lattice_val = CONSTANT;
- val.value = SSA_NAME_VALUE (var);
- }
- else if ((cst_val = get_symbol_constant_value (sym)) != NULL_TREE)
+ prop_value_t val = { UNINITIALIZED, NULL_TREE };
+ gimple stmt;
+
+ stmt = SSA_NAME_DEF_STMT (var);
+
+ if (gimple_nop_p (stmt))
{
- /* Globals and static variables declared 'const' take their
- initial value. */
- val.lattice_val = CONSTANT;
- val.value = cst_val;
- val.mem_ref = sym;
+ /* Variables defined by an empty statement are those used
+ before being initialized. If VAR is a local variable, we
+ can assume initially that it is UNDEFINED, otherwise we must
+ consider it VARYING. */
+ if (is_gimple_reg (sym) && TREE_CODE (sym) != PARM_DECL)
+ val.lattice_val = UNDEFINED;
+ else
+ val.lattice_val = VARYING;
}
- else
- {
- tree stmt = SSA_NAME_DEF_STMT (var);
-
- if (IS_EMPTY_STMT (stmt))
- {
- /* Variables defined by an empty statement are those used
- before being initialized. If VAR is a local variable, we
- can assume initially that it is UNDEFINED, otherwise we must
- consider it VARYING. */
- if (is_gimple_reg (sym) && TREE_CODE (sym) != PARM_DECL)
- val.lattice_val = UNDEFINED;
- else
- val.lattice_val = VARYING;
- }
- else if (TREE_CODE (stmt) == GIMPLE_MODIFY_STMT
- || TREE_CODE (stmt) == PHI_NODE)
+ else if (is_gimple_assign (stmt)
+ /* Value-returning GIMPLE_CALL statements assign to
+ a variable, and are treated similarly to GIMPLE_ASSIGN. */
+ || (is_gimple_call (stmt)
+ && gimple_call_lhs (stmt) != NULL_TREE)
+ || gimple_code (stmt) == GIMPLE_PHI)
+ {
+ tree cst;
+ if (gimple_assign_single_p (stmt)
+ && DECL_P (gimple_assign_rhs1 (stmt))
+ && (cst = get_symbol_constant_value (gimple_assign_rhs1 (stmt))))
{
- /* Any other variable defined by an assignment or a PHI node
- is considered UNDEFINED. */
- val.lattice_val = UNDEFINED;
+ val.lattice_val = CONSTANT;
+ val.value = cst;
}
else
- {
- /* Otherwise, VAR will never take on a constant value. */
- val.lattice_val = VARYING;
- }
+ /* Any other variable defined by an assignment or a PHI node
+ is considered UNDEFINED. */
+ val.lattice_val = UNDEFINED;
+ }
+ else
+ {
+ /* Otherwise, VAR will never take on a constant value. */
+ val.lattice_val = VARYING;
}
return val;
static inline prop_value_t *
get_value (tree var)
{
- prop_value_t *val = &const_val[SSA_NAME_VERSION (var)];
+ prop_value_t *val;
+ if (const_val == NULL)
+ return NULL;
+
+ val = &const_val[SSA_NAME_VERSION (var)];
if (val->lattice_val == UNINITIALIZED)
*val = get_default_value (var);
val->lattice_val = VARYING;
val->value = NULL_TREE;
- val->mem_ref = NULL_TREE;
}
/* For float types, modify the value of VAL to make ccp work correctly
{
val->lattice_val = UNDEFINED;
val->value = NULL;
- val->mem_ref = NULL;
return;
}
}
gcc_assert (old_val->lattice_val < new_val.lattice_val
|| (old_val->lattice_val == new_val.lattice_val
&& ((!old_val->value && !new_val.value)
- || operand_equal_p (old_val->value, new_val.value, 0))
- && old_val->mem_ref == new_val.mem_ref));
+ || operand_equal_p (old_val->value, new_val.value, 0))));
if (old_val->lattice_val != new_val.lattice_val)
{
Else return VARYING. */
static ccp_lattice_t
-likely_value (tree stmt)
+likely_value (gimple stmt)
{
bool has_constant_operand, has_undefined_operand, all_undefined_operands;
- stmt_ann_t ann;
tree use;
ssa_op_iter iter;
+ unsigned i;
+
+ enum gimple_code code = gimple_code (stmt);
- ann = stmt_ann (stmt);
+ /* This function appears to be called only for assignments, calls,
+ conditionals, and switches, due to the logic in visit_stmt. */
+ gcc_assert (code == GIMPLE_ASSIGN
+ || code == GIMPLE_CALL
+ || code == GIMPLE_COND
+ || code == GIMPLE_SWITCH);
/* If the statement has volatile operands, it won't fold to a
constant value. */
- if (ann->has_volatile_ops)
- return VARYING;
-
- /* If we are not doing store-ccp, statements with loads
- and/or stores will never fold into a constant. */
- if (!do_store_ccp
- && !ZERO_SSA_OPERANDS (stmt, SSA_OP_ALL_VIRTUALS))
- return VARYING;
-
-
- /* A CALL_EXPR is assumed to be varying. NOTE: This may be overly
- conservative, in the presence of const and pure calls. */
- if (get_call_expr_in (stmt) != NULL_TREE)
- return VARYING;
-
- /* Anything other than assignments and conditional jumps are not
- interesting for CCP. */
- if (TREE_CODE (stmt) != GIMPLE_MODIFY_STMT
- && !(TREE_CODE (stmt) == RETURN_EXPR && get_rhs (stmt) != NULL_TREE)
- && TREE_CODE (stmt) != COND_EXPR
- && TREE_CODE (stmt) != SWITCH_EXPR)
+ if (gimple_has_volatile_ops (stmt))
return VARYING;
- if (is_gimple_min_invariant (get_rhs (stmt)))
- return CONSTANT;
-
+ /* Arrive here for more complex cases. */
has_constant_operand = false;
has_undefined_operand = false;
all_undefined_operands = true;
- FOR_EACH_SSA_TREE_OPERAND (use, stmt, iter, SSA_OP_USE | SSA_OP_VUSE)
+ FOR_EACH_SSA_TREE_OPERAND (use, stmt, iter, SSA_OP_USE)
{
prop_value_t *val = get_value (use);
has_constant_operand = true;
}
+ /* There may be constants in regular rhs operands. */
+ for (i = is_gimple_call (stmt) + gimple_has_lhs (stmt);
+ i < gimple_num_ops (stmt); ++i)
+ {
+ tree op = gimple_op (stmt, i);
+ if (!op || TREE_CODE (op) == SSA_NAME)
+ continue;
+ if (is_gimple_min_invariant (op))
+ has_constant_operand = true;
+ }
+
/* If the operation combines operands like COMPLEX_EXPR make sure to
not mark the result UNDEFINED if only one part of the result is
undefined. */
- if (has_undefined_operand
- && all_undefined_operands)
+ if (has_undefined_operand && all_undefined_operands)
return UNDEFINED;
- else if (TREE_CODE (stmt) == GIMPLE_MODIFY_STMT
- && has_undefined_operand)
+ else if (code == GIMPLE_ASSIGN && has_undefined_operand)
{
- switch (TREE_CODE (GIMPLE_STMT_OPERAND (stmt, 1)))
+ switch (gimple_assign_rhs_code (stmt))
{
/* Unary operators are handled with all_undefined_operands. */
case PLUS_EXPR:
if (has_undefined_operand)
return VARYING;
+ /* We do not consider virtual operands here -- load from read-only
+ memory may have only VARYING virtual operands, but still be
+ constant. */
if (has_constant_operand
- /* We do not consider virtual operands here -- load from read-only
- memory may have only VARYING virtual operands, but still be
- constant. */
- || ZERO_SSA_OPERANDS (stmt, SSA_OP_USE))
+ || gimple_references_memory_p (stmt))
return CONSTANT;
return VARYING;
/* Returns true if STMT cannot be constant. */
static bool
-surely_varying_stmt_p (tree stmt)
+surely_varying_stmt_p (gimple stmt)
{
/* If the statement has operands that we cannot handle, it cannot be
constant. */
- if (stmt_ann (stmt)->has_volatile_ops)
+ if (gimple_has_volatile_ops (stmt))
return true;
- if (!ZERO_SSA_OPERANDS (stmt, SSA_OP_ALL_VIRTUALS))
+ /* If it is a call and does not return a value or is not a
+ builtin and not an indirect call, it is varying. */
+ if (is_gimple_call (stmt))
{
- if (!do_store_ccp)
- return true;
-
- /* We can only handle simple loads and stores. */
- if (!stmt_makes_single_load (stmt)
- && !stmt_makes_single_store (stmt))
+ tree fndecl;
+ if (!gimple_call_lhs (stmt)
+ || ((fndecl = gimple_call_fndecl (stmt)) != NULL_TREE
+ && !DECL_BUILT_IN (fndecl)))
return true;
}
- /* If it contains a call, it is varying. */
- if (get_call_expr_in (stmt) != NULL_TREE)
+ /* Any other store operation is not interesting. */
+ else if (!ZERO_SSA_OPERANDS (stmt, SSA_OP_VIRTUAL_DEFS))
return true;
/* Anything other than assignments and conditional jumps are not
interesting for CCP. */
- if (TREE_CODE (stmt) != GIMPLE_MODIFY_STMT
- && !(TREE_CODE (stmt) == RETURN_EXPR && get_rhs (stmt) != NULL_TREE)
- && TREE_CODE (stmt) != COND_EXPR
- && TREE_CODE (stmt) != SWITCH_EXPR)
+ if (gimple_code (stmt) != GIMPLE_ASSIGN
+ && gimple_code (stmt) != GIMPLE_COND
+ && gimple_code (stmt) != GIMPLE_SWITCH
+ && gimple_code (stmt) != GIMPLE_CALL)
return true;
return false;
/* Initialize simulation flags for PHI nodes and statements. */
FOR_EACH_BB (bb)
{
- block_stmt_iterator i;
+ gimple_stmt_iterator i;
- for (i = bsi_start (bb); !bsi_end_p (i); bsi_next (&i))
+ for (i = gsi_start_bb (bb); !gsi_end_p (i); gsi_next (&i))
{
- tree stmt = bsi_stmt (i);
+ gimple stmt = gsi_stmt (i);
bool is_varying = surely_varying_stmt_p (stmt);
if (is_varying)
/* If the statement will not produce a constant, mark
all its outputs VARYING. */
FOR_EACH_SSA_TREE_OPERAND (def, stmt, iter, SSA_OP_ALL_DEFS)
- {
- if (is_varying)
- set_value_varying (def);
- }
+ set_value_varying (def);
}
-
- DONT_SIMULATE_AGAIN (stmt) = is_varying;
+ prop_set_simulate_again (stmt, !is_varying);
}
}
- /* Now process PHI nodes. We never set DONT_SIMULATE_AGAIN on phi node,
- since we do not know which edges are executable yet, except for
- phi nodes for virtual operands when we do not do store ccp. */
+ /* Now process PHI nodes. We never clear the simulate_again flag on
+ phi nodes, since we do not know which edges are executable yet,
+ except for phi nodes for virtual operands when we do not do store ccp. */
FOR_EACH_BB (bb)
{
- tree phi;
+ gimple_stmt_iterator i;
- for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi))
- {
- if (!do_store_ccp && !is_gimple_reg (PHI_RESULT (phi)))
- DONT_SIMULATE_AGAIN (phi) = true;
+ for (i = gsi_start_phis (bb); !gsi_end_p (i); gsi_next (&i))
+ {
+ gimple phi = gsi_stmt (i);
+
+ if (!is_gimple_reg (gimple_phi_result (phi)))
+ prop_set_simulate_again (phi, false);
else
- DONT_SIMULATE_AGAIN (phi) = false;
+ prop_set_simulate_again (phi, true);
}
}
}
+/* Debug count support. Reset the values of ssa names
+ VARYING when the total number ssa names analyzed is
+ beyond the debug count specified. */
+
+static void
+do_dbg_cnt (void)
+{
+ unsigned i;
+ for (i = 0; i < num_ssa_names; i++)
+ {
+ if (!dbg_cnt (ccp))
+ {
+ const_val[i].lattice_val = VARYING;
+ const_val[i].value = NULL_TREE;
+ }
+ }
+}
+
/* Do final substitution of propagated values, cleanup the flowgraph and
free allocated storage.
static bool
ccp_finalize (void)
{
+ bool something_changed;
+
+ do_dbg_cnt ();
/* Perform substitutions based on the known constant values. */
- bool something_changed = substitute_and_fold (const_val, false);
+ something_changed = substitute_and_fold (const_val, false);
free (const_val);
+ const_val = NULL;
return something_changed;;
}
/* any M VARYING = VARYING. */
val1->lattice_val = VARYING;
val1->value = NULL_TREE;
- val1->mem_ref = NULL_TREE;
}
else if (val1->lattice_val == CONSTANT
&& val2->lattice_val == CONSTANT
- && simple_cst_equal (val1->value, val2->value) == 1
- && (!do_store_ccp
- || (val1->mem_ref && val2->mem_ref
- && operand_equal_p (val1->mem_ref, val2->mem_ref, 0))))
+ && simple_cst_equal (val1->value, val2->value) == 1)
{
/* Ci M Cj = Ci if (i == j)
Ci M Cj = VARYING if (i != j)
they come from the same memory reference. */
val1->lattice_val = CONSTANT;
val1->value = val1->value;
- val1->mem_ref = val1->mem_ref;
}
else
{
/* Any other combination is VARYING. */
val1->lattice_val = VARYING;
val1->value = NULL_TREE;
- val1->mem_ref = NULL_TREE;
}
}
of the PHI node that are incoming via executable edges. */
static enum ssa_prop_result
-ccp_visit_phi_node (tree phi)
+ccp_visit_phi_node (gimple phi)
{
- int i;
+ unsigned i;
prop_value_t *old_val, new_val;
if (dump_file && (dump_flags & TDF_DETAILS))
{
fprintf (dump_file, "\nVisiting PHI node: ");
- print_generic_expr (dump_file, phi, dump_flags);
+ print_gimple_stmt (dump_file, phi, 0, dump_flags);
}
- old_val = get_value (PHI_RESULT (phi));
+ old_val = get_value (gimple_phi_result (phi));
switch (old_val->lattice_val)
{
case VARYING:
case UNDEFINED:
new_val.lattice_val = UNDEFINED;
new_val.value = NULL_TREE;
- new_val.mem_ref = NULL_TREE;
break;
default:
gcc_unreachable ();
}
- for (i = 0; i < PHI_NUM_ARGS (phi); i++)
+ for (i = 0; i < gimple_phi_num_args (phi); i++)
{
/* Compute the meet operator over all the PHI arguments flowing
through executable edges. */
- edge e = PHI_ARG_EDGE (phi, i);
+ edge e = gimple_phi_arg_edge (phi, i);
if (dump_file && (dump_flags & TDF_DETAILS))
{
the existing value of the PHI node and the current PHI argument. */
if (e->flags & EDGE_EXECUTABLE)
{
- tree arg = PHI_ARG_DEF (phi, i);
+ tree arg = gimple_phi_arg (phi, i)->def;
prop_value_t arg_val;
if (is_gimple_min_invariant (arg))
{
arg_val.lattice_val = CONSTANT;
arg_val.value = arg;
- arg_val.mem_ref = NULL_TREE;
}
else
arg_val = *(get_value (arg));
}
/* Make the transition to the new value. */
- if (set_lattice_value (PHI_RESULT (phi), new_val))
+ if (set_lattice_value (gimple_phi_result (phi), new_val))
{
if (new_val.lattice_val == VARYING)
return SSA_PROP_VARYING;
return SSA_PROP_NOT_INTERESTING;
}
+/* Return true if we may propagate the address expression ADDR into the
+ dereference DEREF and cancel them. */
+
+bool
+may_propagate_address_into_dereference (tree addr, tree deref)
+{
+ gcc_assert (INDIRECT_REF_P (deref)
+ && TREE_CODE (addr) == ADDR_EXPR);
+
+ /* Don't propagate if ADDR's operand has incomplete type. */
+ if (!COMPLETE_TYPE_P (TREE_TYPE (TREE_OPERAND (addr, 0))))
+ return false;
+
+ /* If the address is invariant then we do not need to preserve restrict
+ qualifications. But we do need to preserve volatile qualifiers until
+ we can annotate the folded dereference itself properly. */
+ if (is_gimple_min_invariant (addr)
+ && (!TREE_THIS_VOLATILE (deref)
+ || TYPE_VOLATILE (TREE_TYPE (addr))))
+ return useless_type_conversion_p (TREE_TYPE (deref),
+ TREE_TYPE (TREE_OPERAND (addr, 0)));
+
+ /* Else both the address substitution and the folding must result in
+ a valid useless type conversion sequence. */
+ return (useless_type_conversion_p (TREE_TYPE (TREE_OPERAND (deref, 0)),
+ TREE_TYPE (addr))
+ && useless_type_conversion_p (TREE_TYPE (deref),
+ TREE_TYPE (TREE_OPERAND (addr, 0))));
+}
/* CCP specific front-end to the non-destructive constant folding
routines.
operands are constants.
If simplification is possible, return the simplified RHS,
- otherwise return the original RHS. */
+ otherwise return the original RHS or NULL_TREE. */
static tree
-ccp_fold (tree stmt)
+ccp_fold (gimple stmt)
{
- tree rhs = get_rhs (stmt);
- enum tree_code code = TREE_CODE (rhs);
- enum tree_code_class kind = TREE_CODE_CLASS (code);
- tree retval = NULL_TREE;
-
- if (TREE_CODE (rhs) == SSA_NAME)
+ switch (gimple_code (stmt))
{
- /* If the RHS is an SSA_NAME, return its known constant value,
- if any. */
- return get_value (rhs)->value;
- }
- else if (do_store_ccp && stmt_makes_single_load (stmt))
- {
- /* If the RHS is a memory load, see if the VUSEs associated with
- it are a valid constant for that memory load. */
- prop_value_t *val = get_value_loaded_by (stmt, const_val);
- if (val && val->mem_ref)
- {
- if (operand_equal_p (val->mem_ref, rhs, 0))
- return val->value;
-
- /* If RHS is extracting REALPART_EXPR or IMAGPART_EXPR of a
- complex type with a known constant value, return it. */
- if ((TREE_CODE (rhs) == REALPART_EXPR
- || TREE_CODE (rhs) == IMAGPART_EXPR)
- && operand_equal_p (val->mem_ref, TREE_OPERAND (rhs, 0), 0))
- return fold_build1 (TREE_CODE (rhs), TREE_TYPE (rhs), val->value);
- }
- return NULL_TREE;
- }
+ case GIMPLE_ASSIGN:
+ {
+ enum tree_code subcode = gimple_assign_rhs_code (stmt);
+
+ switch (get_gimple_rhs_class (subcode))
+ {
+ case GIMPLE_SINGLE_RHS:
+ {
+ tree rhs = gimple_assign_rhs1 (stmt);
+ enum tree_code_class kind = TREE_CODE_CLASS (subcode);
+
+ if (TREE_CODE (rhs) == SSA_NAME)
+ {
+ /* If the RHS is an SSA_NAME, return its known constant value,
+ if any. */
+ return get_value (rhs)->value;
+ }
+ /* Handle propagating invariant addresses into address operations.
+ The folding we do here matches that in tree-ssa-forwprop.c. */
+ else if (TREE_CODE (rhs) == ADDR_EXPR)
+ {
+ tree *base;
+ base = &TREE_OPERAND (rhs, 0);
+ while (handled_component_p (*base))
+ base = &TREE_OPERAND (*base, 0);
+ if (TREE_CODE (*base) == INDIRECT_REF
+ && TREE_CODE (TREE_OPERAND (*base, 0)) == SSA_NAME)
+ {
+ prop_value_t *val = get_value (TREE_OPERAND (*base, 0));
+ if (val->lattice_val == CONSTANT
+ && TREE_CODE (val->value) == ADDR_EXPR
+ && may_propagate_address_into_dereference
+ (val->value, *base))
+ {
+ /* We need to return a new tree, not modify the IL
+ or share parts of it. So play some tricks to
+ avoid manually building it. */
+ tree ret, save = *base;
+ *base = TREE_OPERAND (val->value, 0);
+ ret = unshare_expr (rhs);
+ recompute_tree_invariant_for_addr_expr (ret);
+ *base = save;
+ return ret;
+ }
+ }
+ }
- /* Unary operators. Note that we know the single operand must
- be a constant. So this should almost always return a
- simplified RHS. */
- if (kind == tcc_unary)
- {
- /* Handle unary operators which can appear in GIMPLE form. */
- tree op0 = TREE_OPERAND (rhs, 0);
+ if (kind == tcc_reference)
+ {
+ if (TREE_CODE (rhs) == VIEW_CONVERT_EXPR
+ && TREE_CODE (TREE_OPERAND (rhs, 0)) == SSA_NAME)
+ {
+ prop_value_t *val = get_value (TREE_OPERAND (rhs, 0));
+ if (val->lattice_val == CONSTANT)
+ return fold_unary (VIEW_CONVERT_EXPR,
+ TREE_TYPE (rhs), val->value);
+ }
+ else if (TREE_CODE (rhs) == INDIRECT_REF
+ && TREE_CODE (TREE_OPERAND (rhs, 0)) == SSA_NAME)
+ {
+ prop_value_t *val = get_value (TREE_OPERAND (rhs, 0));
+ if (val->lattice_val == CONSTANT
+ && TREE_CODE (val->value) == ADDR_EXPR
+ && useless_type_conversion_p (TREE_TYPE (rhs),
+ TREE_TYPE (TREE_TYPE (val->value))))
+ rhs = TREE_OPERAND (val->value, 0);
+ }
+ return fold_const_aggregate_ref (rhs);
+ }
+ else if (kind == tcc_declaration)
+ return get_symbol_constant_value (rhs);
+ return rhs;
+ }
+
+ case GIMPLE_UNARY_RHS:
+ {
+ /* Handle unary operators that can appear in GIMPLE form.
+ Note that we know the single operand must be a constant,
+ so this should almost always return a simplified RHS. */
+ tree lhs = gimple_assign_lhs (stmt);
+ tree op0 = gimple_assign_rhs1 (stmt);
+
+ /* Simplify the operand down to a constant. */
+ if (TREE_CODE (op0) == SSA_NAME)
+ {
+ prop_value_t *val = get_value (op0);
+ if (val->lattice_val == CONSTANT)
+ op0 = get_value (op0)->value;
+ }
+
+ /* Conversions are useless for CCP purposes if they are
+ value-preserving. Thus the restrictions that
+ useless_type_conversion_p places for pointer type conversions
+ do not apply here. Substitution later will only substitute to
+ allowed places. */
+ if (CONVERT_EXPR_CODE_P (subcode)
+ && POINTER_TYPE_P (TREE_TYPE (lhs))
+ && POINTER_TYPE_P (TREE_TYPE (op0))
+ /* Do not allow differences in volatile qualification
+ as this might get us confused as to whether a
+ propagation destination statement is volatile
+ or not. See PR36988. */
+ && (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (lhs)))
+ == TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (op0)))))
+ {
+ tree tem;
+ /* Still try to generate a constant of correct type. */
+ if (!useless_type_conversion_p (TREE_TYPE (lhs),
+ TREE_TYPE (op0))
+ && ((tem = maybe_fold_offset_to_address
+ (op0, integer_zero_node, TREE_TYPE (lhs)))
+ != NULL_TREE))
+ return tem;
+ return op0;
+ }
- /* Simplify the operand down to a constant. */
- if (TREE_CODE (op0) == SSA_NAME)
- {
- prop_value_t *val = get_value (op0);
- if (val->lattice_val == CONSTANT)
- op0 = get_value (op0)->value;
- }
+ return fold_unary_ignore_overflow (subcode,
+ gimple_expr_type (stmt), op0);
+ }
+
+ case GIMPLE_BINARY_RHS:
+ {
+ /* Handle binary operators that can appear in GIMPLE form. */
+ tree op0 = gimple_assign_rhs1 (stmt);
+ tree op1 = gimple_assign_rhs2 (stmt);
+
+ /* Simplify the operands down to constants when appropriate. */
+ if (TREE_CODE (op0) == SSA_NAME)
+ {
+ prop_value_t *val = get_value (op0);
+ if (val->lattice_val == CONSTANT)
+ op0 = val->value;
+ }
+
+ if (TREE_CODE (op1) == SSA_NAME)
+ {
+ prop_value_t *val = get_value (op1);
+ if (val->lattice_val == CONSTANT)
+ op1 = val->value;
+ }
+
+ /* Fold &foo + CST into an invariant reference if possible. */
+ if (gimple_assign_rhs_code (stmt) == POINTER_PLUS_EXPR
+ && TREE_CODE (op0) == ADDR_EXPR
+ && TREE_CODE (op1) == INTEGER_CST)
+ {
+ tree lhs = gimple_assign_lhs (stmt);
+ tree tem = maybe_fold_offset_to_address (op0, op1,
+ TREE_TYPE (lhs));
+ if (tem != NULL_TREE)
+ return tem;
+ }
- if ((code == NOP_EXPR || code == CONVERT_EXPR)
- && useless_type_conversion_p (TREE_TYPE (rhs), TREE_TYPE (op0)))
- return op0;
- return fold_unary (code, TREE_TYPE (rhs), op0);
- }
+ return fold_binary (subcode, gimple_expr_type (stmt), op0, op1);
+ }
- /* Binary and comparison operators. We know one or both of the
- operands are constants. */
- else if (kind == tcc_binary
- || kind == tcc_comparison
- || code == TRUTH_AND_EXPR
- || code == TRUTH_OR_EXPR
- || code == TRUTH_XOR_EXPR)
- {
- /* Handle binary and comparison operators that can appear in
- GIMPLE form. */
- tree op0 = TREE_OPERAND (rhs, 0);
- tree op1 = TREE_OPERAND (rhs, 1);
+ default:
+ gcc_unreachable ();
+ }
+ }
+ break;
- /* Simplify the operands down to constants when appropriate. */
- if (TREE_CODE (op0) == SSA_NAME)
- {
- prop_value_t *val = get_value (op0);
- if (val->lattice_val == CONSTANT)
- op0 = val->value;
- }
+ case GIMPLE_CALL:
+ {
+ tree fn = gimple_call_fn (stmt);
+ prop_value_t *val;
- if (TREE_CODE (op1) == SSA_NAME)
- {
- prop_value_t *val = get_value (op1);
- if (val->lattice_val == CONSTANT)
- op1 = val->value;
- }
+ if (TREE_CODE (fn) == SSA_NAME)
+ {
+ val = get_value (fn);
+ if (val->lattice_val == CONSTANT)
+ fn = val->value;
+ }
+ if (TREE_CODE (fn) == ADDR_EXPR
+ && TREE_CODE (TREE_OPERAND (fn, 0)) == FUNCTION_DECL
+ && DECL_BUILT_IN (TREE_OPERAND (fn, 0)))
+ {
+ tree *args = XALLOCAVEC (tree, gimple_call_num_args (stmt));
+ tree call, retval;
+ unsigned i;
+ for (i = 0; i < gimple_call_num_args (stmt); ++i)
+ {
+ args[i] = gimple_call_arg (stmt, i);
+ if (TREE_CODE (args[i]) == SSA_NAME)
+ {
+ val = get_value (args[i]);
+ if (val->lattice_val == CONSTANT)
+ args[i] = val->value;
+ }
+ }
+ call = build_call_array (gimple_call_return_type (stmt),
+ fn, gimple_call_num_args (stmt), args);
+ retval = fold_call_expr (call, false);
+ if (retval)
+ /* fold_call_expr wraps the result inside a NOP_EXPR. */
+ STRIP_NOPS (retval);
+ return retval;
+ }
+ return NULL_TREE;
+ }
- return fold_binary (code, TREE_TYPE (rhs), op0, op1);
- }
+ case GIMPLE_COND:
+ {
+ /* Handle comparison operators that can appear in GIMPLE form. */
+ tree op0 = gimple_cond_lhs (stmt);
+ tree op1 = gimple_cond_rhs (stmt);
+ enum tree_code code = gimple_cond_code (stmt);
+
+ /* Simplify the operands down to constants when appropriate. */
+ if (TREE_CODE (op0) == SSA_NAME)
+ {
+ prop_value_t *val = get_value (op0);
+ if (val->lattice_val == CONSTANT)
+ op0 = val->value;
+ }
+
+ if (TREE_CODE (op1) == SSA_NAME)
+ {
+ prop_value_t *val = get_value (op1);
+ if (val->lattice_val == CONSTANT)
+ op1 = val->value;
+ }
+
+ return fold_binary (code, boolean_type_node, op0, op1);
+ }
- /* We may be able to fold away calls to builtin functions if their
- arguments are constants. */
- else if (code == CALL_EXPR
- && TREE_CODE (CALL_EXPR_FN (rhs)) == ADDR_EXPR
- && TREE_CODE (TREE_OPERAND (CALL_EXPR_FN (rhs), 0)) == FUNCTION_DECL
- && DECL_BUILT_IN (TREE_OPERAND (CALL_EXPR_FN (rhs), 0)))
- {
- if (!ZERO_SSA_OPERANDS (stmt, SSA_OP_USE))
- {
- tree *orig, var;
- size_t i = 0;
- ssa_op_iter iter;
- use_operand_p var_p;
-
- /* Preserve the original values of every operand. */
- orig = XNEWVEC (tree, NUM_SSA_OPERANDS (stmt, SSA_OP_USE));
- FOR_EACH_SSA_TREE_OPERAND (var, stmt, iter, SSA_OP_USE)
- orig[i++] = var;
-
- /* Substitute operands with their values and try to fold. */
- replace_uses_in (stmt, NULL, const_val);
- retval = fold_call_expr (rhs, false);
-
- /* Restore operands to their original form. */
- i = 0;
- FOR_EACH_SSA_USE_OPERAND (var_p, stmt, iter, SSA_OP_USE)
- SET_USE (var_p, orig[i++]);
- free (orig);
- }
- }
- else
- return rhs;
+ case GIMPLE_SWITCH:
+ {
+ tree rhs = gimple_switch_index (stmt);
- /* If we got a simplified form, see if we need to convert its type. */
- if (retval)
- return fold_convert (TREE_TYPE (rhs), retval);
+ if (TREE_CODE (rhs) == SSA_NAME)
+ {
+ /* If the RHS is an SSA_NAME, return its known constant value,
+ if any. */
+ return get_value (rhs)->value;
+ }
- /* No simplification was possible. */
- return rhs;
+ return rhs;
+ }
+
+ default:
+ gcc_unreachable ();
+ }
}
ARRAY_REF or COMPONENT_REF into constant aggregates. Return
NULL_TREE otherwise. */
-static tree
+tree
fold_const_aggregate_ref (tree t)
{
prop_value_t *value;
unsigned HOST_WIDE_INT cnt;
tree cfield, cval;
+ if (TREE_CODE_CLASS (TREE_CODE (t)) == tcc_declaration)
+ return get_symbol_constant_value (t);
+
switch (TREE_CODE (t))
{
case ARRAY_REF:
ctor = fold_const_aggregate_ref (base);
break;
+ case STRING_CST:
+ case CONSTRUCTOR:
+ ctor = base;
+ break;
+
default:
return NULL_TREE;
}
/* Whoo-hoo! I'll fold ya baby. Yeah! */
FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (ctor), cnt, cfield, cval)
if (tree_int_cst_equal (cfield, idx))
- return cval;
+ {
+ STRIP_USELESS_TYPE_CONVERSION (cval);
+ return cval;
+ }
break;
case COMPONENT_REF:
if (cfield == field
/* FIXME: Handle bit-fields. */
&& ! DECL_BIT_FIELD (cfield))
- return cval;
+ {
+ STRIP_USELESS_TYPE_CONVERSION (cval);
+ return cval;
+ }
break;
case REALPART_EXPR:
return fold_build1 (TREE_CODE (t), TREE_TYPE (t), c);
break;
}
-
+
+ case INDIRECT_REF:
+ {
+ tree base = TREE_OPERAND (t, 0);
+ if (TREE_CODE (base) == SSA_NAME
+ && (value = get_value (base))
+ && value->lattice_val == CONSTANT
+ && TREE_CODE (value->value) == ADDR_EXPR)
+ return fold_const_aggregate_ref (TREE_OPERAND (value->value, 0));
+ break;
+ }
+
default:
break;
}
return NULL_TREE;
}
-
-/* Evaluate statement STMT. */
+
+/* Evaluate statement STMT.
+ Valid only for assignments, calls, conditionals, and switches. */
static prop_value_t
-evaluate_stmt (tree stmt)
+evaluate_stmt (gimple stmt)
{
prop_value_t val;
tree simplified = NULL_TREE;
ccp_lattice_t likelyvalue = likely_value (stmt);
bool is_constant;
- val.mem_ref = NULL_TREE;
-
fold_defer_overflow_warnings ();
/* If the statement is likely to have a CONSTANT result, then try
to fold the statement to determine the constant value. */
+ /* FIXME. This is the only place that we call ccp_fold.
+ Since likely_value never returns CONSTANT for calls, we will
+ not attempt to fold them, including builtins that may profit. */
if (likelyvalue == CONSTANT)
simplified = ccp_fold (stmt);
/* If the statement is likely to have a VARYING result, then do not
bother folding the statement. */
- if (likelyvalue == VARYING)
- simplified = get_rhs (stmt);
- /* If the statement is an ARRAY_REF or COMPONENT_REF into constant
- aggregates, extract the referenced constant. Otherwise the
- statement is likely to have an UNDEFINED value, and there will be
- nothing to do. Note that fold_const_aggregate_ref returns
- NULL_TREE if the first case does not match. */
- else if (!simplified)
- simplified = fold_const_aggregate_ref (get_rhs (stmt));
+ else if (likelyvalue == VARYING)
+ {
+ enum gimple_code code = gimple_code (stmt);
+ if (code == GIMPLE_ASSIGN)
+ {
+ enum tree_code subcode = gimple_assign_rhs_code (stmt);
+
+ /* Other cases cannot satisfy is_gimple_min_invariant
+ without folding. */
+ if (get_gimple_rhs_class (subcode) == GIMPLE_SINGLE_RHS)
+ simplified = gimple_assign_rhs1 (stmt);
+ }
+ else if (code == GIMPLE_SWITCH)
+ simplified = gimple_switch_index (stmt);
+ else
+ /* These cannot satisfy is_gimple_min_invariant without folding. */
+ gcc_assert (code == GIMPLE_CALL || code == GIMPLE_COND);
+ }
is_constant = simplified && is_gimple_min_invariant (simplified);
fold_undefer_overflow_warnings (is_constant, stmt, 0);
+ if (dump_file && (dump_flags & TDF_DETAILS))
+ {
+ fprintf (dump_file, "which is likely ");
+ switch (likelyvalue)
+ {
+ case CONSTANT:
+ fprintf (dump_file, "CONSTANT");
+ break;
+ case UNDEFINED:
+ fprintf (dump_file, "UNDEFINED");
+ break;
+ case VARYING:
+ fprintf (dump_file, "VARYING");
+ break;
+ default:;
+ }
+ fprintf (dump_file, "\n");
+ }
+
if (is_constant)
{
/* The statement produced a constant value. */
return val;
}
-
/* Visit the assignment statement STMT. Set the value of its LHS to the
value computed by the RHS and store LHS in *OUTPUT_P. If STMT
creates virtual definitions, set the value of each new name to that
- of the RHS (if we can derive a constant out of the RHS). */
+ of the RHS (if we can derive a constant out of the RHS).
+ Value-returning call statements also perform an assignment, and
+ are handled here. */
static enum ssa_prop_result
-visit_assignment (tree stmt, tree *output_p)
+visit_assignment (gimple stmt, tree *output_p)
{
prop_value_t val;
- tree lhs, rhs;
enum ssa_prop_result retval;
- lhs = GIMPLE_STMT_OPERAND (stmt, 0);
- rhs = GIMPLE_STMT_OPERAND (stmt, 1);
+ tree lhs = gimple_get_lhs (stmt);
- if (TREE_CODE (rhs) == SSA_NAME)
- {
- /* For a simple copy operation, we copy the lattice values. */
- prop_value_t *nval = get_value (rhs);
- val = *nval;
- }
- else if (do_store_ccp && stmt_makes_single_load (stmt))
+ gcc_assert (gimple_code (stmt) != GIMPLE_CALL
+ || gimple_call_lhs (stmt) != NULL_TREE);
+
+ if (gimple_assign_copy_p (stmt))
{
- /* Same as above, but the RHS is not a gimple register and yet
- has a known VUSE. If STMT is loading from the same memory
- location that created the SSA_NAMEs for the virtual operands,
- we can propagate the value on the RHS. */
- prop_value_t *nval = get_value_loaded_by (stmt, const_val);
+ tree rhs = gimple_assign_rhs1 (stmt);
- if (nval
- && nval->mem_ref
- && operand_equal_p (nval->mem_ref, rhs, 0))
- val = *nval;
+ if (TREE_CODE (rhs) == SSA_NAME)
+ {
+ /* For a simple copy operation, we copy the lattice values. */
+ prop_value_t *nval = get_value (rhs);
+ val = *nval;
+ }
else
- val = evaluate_stmt (stmt);
+ val = evaluate_stmt (stmt);
}
else
- /* Evaluate the statement. */
- val = evaluate_stmt (stmt);
-
- /* If the original LHS was a VIEW_CONVERT_EXPR, modify the constant
- value to be a VIEW_CONVERT_EXPR of the old constant value.
-
- ??? Also, if this was a definition of a bitfield, we need to widen
- the constant value into the type of the destination variable. This
- should not be necessary if GCC represented bitfields properly. */
- {
- tree orig_lhs = GIMPLE_STMT_OPERAND (stmt, 0);
-
- if (TREE_CODE (orig_lhs) == VIEW_CONVERT_EXPR
- && val.lattice_val == CONSTANT)
- {
- tree w = fold_unary (VIEW_CONVERT_EXPR,
- TREE_TYPE (TREE_OPERAND (orig_lhs, 0)),
- val.value);
-
- orig_lhs = TREE_OPERAND (orig_lhs, 0);
- if (w && is_gimple_min_invariant (w))
- val.value = w;
- else
- {
- val.lattice_val = VARYING;
- val.value = NULL;
- }
- }
-
- if (val.lattice_val == CONSTANT
- && TREE_CODE (orig_lhs) == COMPONENT_REF
- && DECL_BIT_FIELD (TREE_OPERAND (orig_lhs, 1)))
- {
- tree w = widen_bitfield (val.value, TREE_OPERAND (orig_lhs, 1),
- orig_lhs);
-
- if (w && is_gimple_min_invariant (w))
- val.value = w;
- else
- {
- val.lattice_val = VARYING;
- val.value = NULL_TREE;
- val.mem_ref = NULL_TREE;
- }
- }
- }
+ /* Evaluate the statement, which could be
+ either a GIMPLE_ASSIGN or a GIMPLE_CALL. */
+ val = evaluate_stmt (stmt);
retval = SSA_PROP_NOT_INTERESTING;
retval = SSA_PROP_INTERESTING;
}
}
- else if (do_store_ccp && stmt_makes_single_store (stmt))
- {
- /* Otherwise, set the names in VDEF operands to the new
- constant value and mark the LHS as the memory reference
- associated with VAL. */
- ssa_op_iter i;
- tree vdef;
- bool changed;
-
- /* Mark VAL as stored in the LHS of this assignment. */
- if (val.lattice_val == CONSTANT)
- val.mem_ref = lhs;
-
- /* Set the value of every VDEF to VAL. */
- changed = false;
- FOR_EACH_SSA_TREE_OPERAND (vdef, stmt, i, SSA_OP_VIRTUAL_DEFS)
- {
- /* See PR 29801. We may have VDEFs for read-only variables
- (see the handling of unmodifiable variables in
- add_virtual_operand); do not attempt to change their value. */
- if (get_symbol_constant_value (SSA_NAME_VAR (vdef)) != NULL_TREE)
- continue;
-
- changed |= set_lattice_value (vdef, val);
- }
-
- /* Note that for propagation purposes, we are only interested in
- visiting statements that load the exact same memory reference
- stored here. Those statements will have the exact same list
- of virtual uses, so it is enough to set the output of this
- statement to be its first virtual definition. */
- *output_p = first_vdef (stmt);
- if (changed)
- {
- if (val.lattice_val == VARYING)
- retval = SSA_PROP_VARYING;
- else
- retval = SSA_PROP_INTERESTING;
- }
- }
return retval;
}
SSA_PROP_VARYING. */
static enum ssa_prop_result
-visit_cond_stmt (tree stmt, edge *taken_edge_p)
+visit_cond_stmt (gimple stmt, edge *taken_edge_p)
{
prop_value_t val;
basic_block block;
- block = bb_for_stmt (stmt);
+ block = gimple_bb (stmt);
val = evaluate_stmt (stmt);
/* Find which edge out of the conditional block will be taken and add it
value, return SSA_PROP_VARYING. */
static enum ssa_prop_result
-ccp_visit_stmt (tree stmt, edge *taken_edge_p, tree *output_p)
+ccp_visit_stmt (gimple stmt, edge *taken_edge_p, tree *output_p)
{
tree def;
ssa_op_iter iter;
if (dump_file && (dump_flags & TDF_DETAILS))
{
fprintf (dump_file, "\nVisiting statement:\n");
- print_generic_stmt (dump_file, stmt, dump_flags);
- fprintf (dump_file, "\n");
+ print_gimple_stmt (dump_file, stmt, 0, dump_flags);
}
- if (TREE_CODE (stmt) == GIMPLE_MODIFY_STMT)
+ switch (gimple_code (stmt))
{
- /* If the statement is an assignment that produces a single
- output value, evaluate its RHS to see if the lattice value of
- its output has changed. */
- return visit_assignment (stmt, output_p);
- }
- else if (TREE_CODE (stmt) == COND_EXPR || TREE_CODE (stmt) == SWITCH_EXPR)
- {
- /* If STMT is a conditional branch, see if we can determine
- which branch will be taken. */
- return visit_cond_stmt (stmt, taken_edge_p);
+ case GIMPLE_ASSIGN:
+ /* If the statement is an assignment that produces a single
+ output value, evaluate its RHS to see if the lattice value of
+ its output has changed. */
+ return visit_assignment (stmt, output_p);
+
+ case GIMPLE_CALL:
+ /* A value-returning call also performs an assignment. */
+ if (gimple_call_lhs (stmt) != NULL_TREE)
+ return visit_assignment (stmt, output_p);
+ break;
+
+ case GIMPLE_COND:
+ case GIMPLE_SWITCH:
+ /* If STMT is a conditional branch, see if we can determine
+ which branch will be taken. */
+ /* FIXME. It appears that we should be able to optimize
+ computed GOTOs here as well. */
+ return visit_cond_stmt (stmt, taken_edge_p);
+
+ default:
+ break;
}
/* Any other kind of statement is not interesting for constant
Mark them VARYING. */
FOR_EACH_SSA_TREE_OPERAND (def, stmt, iter, SSA_OP_ALL_DEFS)
{
- prop_value_t v = { VARYING, NULL_TREE, NULL_TREE };
+ prop_value_t v = { VARYING, NULL_TREE };
set_lattice_value (def, v);
}
/* Main entry point for SSA Conditional Constant Propagation. */
static unsigned int
-execute_ssa_ccp (bool store_ccp)
+do_ssa_ccp (void)
{
- do_store_ccp = store_ccp;
ccp_initialize ();
ssa_propagate (ccp_visit_stmt, ccp_visit_phi_node);
if (ccp_finalize ())
}
-static unsigned int
-do_ssa_ccp (void)
-{
- return execute_ssa_ccp (false);
-}
-
-
static bool
gate_ccp (void)
{
}
-struct tree_opt_pass pass_ccp =
+struct gimple_opt_pass pass_ccp =
{
+ {
+ GIMPLE_PASS,
"ccp", /* name */
gate_ccp, /* gate */
do_ssa_ccp, /* execute */
0, /* properties_destroyed */
0, /* todo_flags_start */
TODO_dump_func | TODO_verify_ssa
- | TODO_verify_stmts | TODO_ggc_collect,/* todo_flags_finish */
- 0 /* letter */
-};
-
-
-static unsigned int
-do_ssa_store_ccp (void)
-{
- /* If STORE-CCP is not enabled, we just run regular CCP. */
- return execute_ssa_ccp (flag_tree_store_ccp != 0);
-}
-
-static bool
-gate_store_ccp (void)
-{
- /* STORE-CCP is enabled only with -ftree-store-ccp, but when
- -fno-tree-store-ccp is specified, we should run regular CCP.
- That's why the pass is enabled with either flag. */
- return flag_tree_store_ccp != 0 || flag_tree_ccp != 0;
-}
-
-
-struct tree_opt_pass pass_store_ccp =
-{
- "store_ccp", /* name */
- gate_store_ccp, /* gate */
- do_ssa_store_ccp, /* execute */
- NULL, /* sub */
- NULL, /* next */
- 0, /* static_pass_number */
- TV_TREE_STORE_CCP, /* tv_id */
- PROP_cfg | PROP_ssa | PROP_alias, /* properties_required */
- 0, /* properties_provided */
- 0, /* properties_destroyed */
- 0, /* todo_flags_start */
- TODO_dump_func | TODO_verify_ssa
- | TODO_verify_stmts | TODO_ggc_collect,/* todo_flags_finish */
- 0 /* letter */
+ | TODO_verify_stmts | TODO_ggc_collect/* todo_flags_finish */
+ }
};
-/* Given a constant value VAL for bitfield FIELD, and a destination
- variable VAR, return VAL appropriately widened to fit into VAR. If
- FIELD is wider than HOST_WIDE_INT, NULL is returned. */
-
-tree
-widen_bitfield (tree val, tree field, tree var)
-{
- unsigned HOST_WIDE_INT var_size, field_size;
- tree wide_val;
- unsigned HOST_WIDE_INT mask;
- unsigned int i;
-
- /* We can only do this if the size of the type and field and VAL are
- all constants representable in HOST_WIDE_INT. */
- if (!host_integerp (TYPE_SIZE (TREE_TYPE (var)), 1)
- || !host_integerp (DECL_SIZE (field), 1)
- || !host_integerp (val, 0))
- return NULL_TREE;
-
- var_size = tree_low_cst (TYPE_SIZE (TREE_TYPE (var)), 1);
- field_size = tree_low_cst (DECL_SIZE (field), 1);
-
- /* Give up if either the bitfield or the variable are too wide. */
- if (field_size > HOST_BITS_PER_WIDE_INT || var_size > HOST_BITS_PER_WIDE_INT)
- return NULL_TREE;
-
- gcc_assert (var_size >= field_size);
-
- /* If the sign bit of the value is not set or the field's type is unsigned,
- just mask off the high order bits of the value. */
- if (DECL_UNSIGNED (field)
- || !(tree_low_cst (val, 0) & (((HOST_WIDE_INT)1) << (field_size - 1))))
- {
- /* Zero extension. Build a mask with the lower 'field_size' bits
- set and a BIT_AND_EXPR node to clear the high order bits of
- the value. */
- for (i = 0, mask = 0; i < field_size; i++)
- mask |= ((HOST_WIDE_INT) 1) << i;
-
- wide_val = fold_build2 (BIT_AND_EXPR, TREE_TYPE (var), val,
- build_int_cst (TREE_TYPE (var), mask));
- }
- else
- {
- /* Sign extension. Create a mask with the upper 'field_size'
- bits set and a BIT_IOR_EXPR to set the high order bits of the
- value. */
- for (i = 0, mask = 0; i < (var_size - field_size); i++)
- mask |= ((HOST_WIDE_INT) 1) << (var_size - i - 1);
-
- wide_val = fold_build2 (BIT_IOR_EXPR, TREE_TYPE (var), val,
- build_int_cst (TREE_TYPE (var), mask));
- }
-
- return wide_val;
-}
-
/* A subroutine of fold_stmt_r. Attempts to fold *(A+O) to A[X].
BASE is an array type. OFFSET is a byte displacement. ORIG_TYPE
is the desired result type. */
static tree
-maybe_fold_offset_to_array_ref (tree base, tree offset, tree orig_type)
+maybe_fold_offset_to_array_ref (tree base, tree offset, tree orig_type,
+ bool allow_negative_idx)
{
tree min_idx, idx, idx_type, elt_offset = integer_zero_node;
tree array_type, elt_type, elt_size;
idx = fold_convert (idx_type, idx);
/* We don't want to construct access past array bounds. For example
- char *(c[4]);
-
- c[3][2]; should not be simplified into (*c)[14] or tree-vrp will give false
- warning. */
- if (domain_type && TYPE_MAX_VALUE (domain_type)
+ char *(c[4]);
+ c[3][2];
+ should not be simplified into (*c)[14] or tree-vrp will
+ give false warnings. The same is true for
+ struct A { long x; char d[0]; } *a;
+ (char *)a - 4;
+ which should be not folded to &a->d[-8]. */
+ if (domain_type
+ && TYPE_MAX_VALUE (domain_type)
&& TREE_CODE (TYPE_MAX_VALUE (domain_type)) == INTEGER_CST)
{
tree up_bound = TYPE_MAX_VALUE (domain_type);
&& compare_tree_int (up_bound, 1) > 0)
return NULL_TREE;
}
+ if (domain_type
+ && TYPE_MIN_VALUE (domain_type))
+ {
+ if (!allow_negative_idx
+ && TREE_CODE (TYPE_MIN_VALUE (domain_type)) == INTEGER_CST
+ && tree_int_cst_lt (idx, TYPE_MIN_VALUE (domain_type)))
+ return NULL_TREE;
+ }
+ else if (!allow_negative_idx
+ && compare_tree_int (idx, 0) < 0)
+ return NULL_TREE;
return build4 (ARRAY_REF, elt_type, base, idx, NULL_TREE, NULL_TREE);
}
new_base = build3 (COMPONENT_REF, field_type, new_base, f, NULL_TREE);
/* Recurse to possibly find the match. */
- ret = maybe_fold_offset_to_array_ref (new_base, t, orig_type);
+ ret = maybe_fold_offset_to_array_ref (new_base, t, orig_type,
+ f == TYPE_FIELDS (record_type));
if (ret)
return ret;
ret = maybe_fold_offset_to_component_ref (field_type, new_base, t,
base = build1 (INDIRECT_REF, record_type, base);
base = build3 (COMPONENT_REF, field_type, base, f, NULL_TREE);
- t = maybe_fold_offset_to_array_ref (base, offset, orig_type);
+ t = maybe_fold_offset_to_array_ref (base, offset, orig_type,
+ f == TYPE_FIELDS (record_type));
if (t)
return t;
return maybe_fold_offset_to_component_ref (field_type, base, offset,
so it needs to be removed and new COMPONENT_REF constructed.
The wrong COMPONENT_REF are often constructed by folding the
(type *)&object within the expression (type *)&object+offset */
- if (handled_component_p (base) && 0)
+ if (handled_component_p (base))
{
HOST_WIDE_INT sub_offset, size, maxsize;
tree newbase;
newbase = get_ref_base_and_extent (base, &sub_offset,
&size, &maxsize);
gcc_assert (newbase);
- gcc_assert (!(sub_offset & (BITS_PER_UNIT - 1)));
- if (size == maxsize)
+ if (size == maxsize
+ && size != -1
+ && !(sub_offset & (BITS_PER_UNIT - 1)))
{
base = newbase;
if (sub_offset)
{
if (base_is_ptr)
base = build1 (INDIRECT_REF, type, base);
- ret = maybe_fold_offset_to_array_ref (base, offset, orig_type);
+ ret = maybe_fold_offset_to_array_ref (base, offset, orig_type, true);
}
return ret;
}
+/* Attempt to express (ORIG_TYPE)&BASE+OFFSET as &BASE->field_of_orig_type
+ or &BASE[index] or by combination of those.
+
+ Before attempting the conversion strip off existing component refs. */
+
+tree
+maybe_fold_offset_to_address (tree addr, tree offset, tree orig_type)
+{
+ tree t;
+
+ gcc_assert (POINTER_TYPE_P (TREE_TYPE (addr))
+ && POINTER_TYPE_P (orig_type));
+
+ t = maybe_fold_offset_to_reference (addr, offset, TREE_TYPE (orig_type));
+ if (t != NULL_TREE)
+ {
+ tree orig = addr;
+ tree ptr_type;
+
+ /* For __builtin_object_size to function correctly we need to
+ make sure not to fold address arithmetic so that we change
+ reference from one array to another. This would happen for
+ example for
+
+ struct X { char s1[10]; char s2[10] } s;
+ char *foo (void) { return &s.s2[-4]; }
+
+ where we need to avoid generating &s.s1[6]. As the C and
+ C++ frontends create different initial trees
+ (char *) &s.s1 + -4 vs. &s.s1[-4] we have to do some
+ sophisticated comparisons here. Note that checking for the
+ condition after the fact is easier than trying to avoid doing
+ the folding. */
+ STRIP_NOPS (orig);
+ if (TREE_CODE (orig) == ADDR_EXPR)
+ orig = TREE_OPERAND (orig, 0);
+ if ((TREE_CODE (orig) == ARRAY_REF
+ || (TREE_CODE (orig) == COMPONENT_REF
+ && TREE_CODE (TREE_TYPE (TREE_OPERAND (orig, 1))) == ARRAY_TYPE))
+ && (TREE_CODE (t) == ARRAY_REF
+ || TREE_CODE (t) == COMPONENT_REF)
+ && !operand_equal_p (TREE_CODE (orig) == ARRAY_REF
+ ? TREE_OPERAND (orig, 0) : orig,
+ TREE_CODE (t) == ARRAY_REF
+ ? TREE_OPERAND (t, 0) : t, 0))
+ return NULL_TREE;
+
+ ptr_type = build_pointer_type (TREE_TYPE (t));
+ if (!useless_type_conversion_p (orig_type, ptr_type))
+ return NULL_TREE;
+ return build_fold_addr_expr_with_type (t, ptr_type);
+ }
+
+ return NULL_TREE;
+}
+
/* A subroutine of fold_stmt_r. Attempt to simplify *(BASE+OFFSET).
Return the simplified expression, or NULL if nothing could be done. */
/* Fold away CONST_DECL to its value, if the type is scalar. */
if (TREE_CODE (base) == CONST_DECL
- && ccp_decl_initial_min_invariant (DECL_INITIAL (base)))
+ && is_gimple_min_invariant (DECL_INITIAL (base)))
return DECL_INITIAL (base);
/* Try folding *(&B+O) to B.X. */
TREE_TYPE (expr));
if (t)
{
- TREE_THIS_VOLATILE (t) = volatile_p;
+ /* Preserve volatileness of the original expression.
+ We can end up with a plain decl here which is shared
+ and we shouldn't mess with its flags. */
+ if (!SSA_VAR_P (t))
+ TREE_THIS_VOLATILE (t) = volatile_p;
return t;
}
}
}
-/* A subroutine of fold_stmt_r. EXPR is a POINTER_PLUS_EXPR.
-
- A quaint feature extant in our address arithmetic is that there
+/* A quaint feature extant in our address arithmetic is that there
can be hidden type changes here. The type of the result need
not be the same as the type of the input pointer.
What we're after here is an expression of the form
(T *)(&array + const)
- where the cast doesn't actually exist, but is implicit in the
+ where array is OP0, const is OP1, RES_TYPE is T and
+ the cast doesn't actually exist, but is implicit in the
type of the POINTER_PLUS_EXPR. We'd like to turn this into
&array[x]
which may be able to propagate further. */
-static tree
-maybe_fold_stmt_addition (tree expr)
+tree
+maybe_fold_stmt_addition (tree res_type, tree op0, tree op1)
{
- tree op0 = TREE_OPERAND (expr, 0);
- tree op1 = TREE_OPERAND (expr, 1);
- tree ptr_type = TREE_TYPE (expr);
tree ptd_type;
tree t;
- gcc_assert (TREE_CODE (expr) == POINTER_PLUS_EXPR);
-
/* It had better be a constant. */
if (TREE_CODE (op1) != INTEGER_CST)
return NULL_TREE;
op0 = array_obj;
}
- ptd_type = TREE_TYPE (ptr_type);
+ ptd_type = TREE_TYPE (res_type);
+ /* If we want a pointer to void, reconstruct the reference from the
+ array element type. A pointer to that can be trivially converted
+ to void *. This happens as we fold (void *)(ptr p+ off). */
+ if (VOID_TYPE_P (ptd_type)
+ && TREE_CODE (TREE_TYPE (op0)) == ARRAY_TYPE)
+ ptd_type = TREE_TYPE (TREE_TYPE (op0));
/* At which point we can try some of the same things as for indirects. */
- t = maybe_fold_offset_to_array_ref (op0, op1, ptd_type);
+ t = maybe_fold_offset_to_array_ref (op0, op1, ptd_type, true);
if (!t)
t = maybe_fold_offset_to_component_ref (TREE_TYPE (op0), op0, op1,
ptd_type, false);
if (t)
- t = build1 (ADDR_EXPR, ptr_type, t);
+ t = build1 (ADDR_EXPR, res_type, t);
return t;
}
struct fold_stmt_r_data
{
- tree stmt;
+ gimple stmt;
bool *changed_p;
bool *inside_addr_expr_p;
};
static tree
fold_stmt_r (tree *expr_p, int *walk_subtrees, void *data)
{
- struct fold_stmt_r_data *fold_stmt_r_data = (struct fold_stmt_r_data *) data;
- bool *inside_addr_expr_p = fold_stmt_r_data->inside_addr_expr_p;
- bool *changed_p = fold_stmt_r_data->changed_p;
+ struct walk_stmt_info *wi = (struct walk_stmt_info *) data;
+ struct fold_stmt_r_data *fold_stmt_r_data;
+ bool *inside_addr_expr_p;
+ bool *changed_p;
tree expr = *expr_p, t;
bool volatile_p = TREE_THIS_VOLATILE (expr);
+ fold_stmt_r_data = (struct fold_stmt_r_data *) wi->info;
+ inside_addr_expr_p = fold_stmt_r_data->inside_addr_expr_p;
+ changed_p = fold_stmt_r_data->changed_p;
+
/* ??? It'd be nice if walk_tree had a pre-order option. */
switch (TREE_CODE (expr))
{
t = maybe_fold_stmt_indirect (expr, TREE_OPERAND (expr, 0),
integer_zero_node);
+ /* Avoid folding *"abc" = 5 into 'a' = 5. */
+ if (wi->is_lhs && t && TREE_CODE (t) == INTEGER_CST)
+ t = NULL_TREE;
+ if (!t
+ && TREE_CODE (TREE_OPERAND (expr, 0)) == ADDR_EXPR)
+ /* If we had a good reason for propagating the address here,
+ make sure we end up with valid gimple. See PR34989. */
+ t = TREE_OPERAND (TREE_OPERAND (expr, 0), 0);
break;
case NOP_EXPR:
*walk_subtrees = 0;
if (POINTER_TYPE_P (TREE_TYPE (expr))
+ && POINTER_TYPE_P (TREE_TYPE (TREE_TYPE (expr)))
&& POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (expr, 0)))
- && (t = maybe_fold_offset_to_reference
- (TREE_OPERAND (expr, 0),
- integer_zero_node,
- TREE_TYPE (TREE_TYPE (expr)))))
- {
- tree ptr_type = build_pointer_type (TREE_TYPE (t));
- if (!useless_type_conversion_p (TREE_TYPE (expr), ptr_type))
- return NULL_TREE;
- t = build_fold_addr_expr_with_type (t, ptr_type);
- }
+ && (t = maybe_fold_offset_to_address (TREE_OPERAND (expr, 0),
+ integer_zero_node,
+ TREE_TYPE (TREE_TYPE (expr)))))
+ return t;
break;
/* ??? Could handle more ARRAY_REFs here, as a variant of INDIRECT_REF.
Otherwise we'd be wasting time. */
case ARRAY_REF:
/* If we are not processing expressions found within an
- ADDR_EXPR, then we can fold constant array references. */
- if (!*inside_addr_expr_p)
+ ADDR_EXPR, then we can fold constant array references.
+ Don't fold on LHS either, to avoid folding "abc"[0] = 5
+ into 'a' = 5. */
+ if (!*inside_addr_expr_p && !wi->is_lhs)
t = fold_read_from_constant_string (expr);
else
t = NULL;
return t;
*walk_subtrees = 0;
- /* Set TREE_INVARIANT properly so that the value is properly
- considered constant, and so gets propagated as expected. */
+ /* Make sure the value is properly considered constant, and so gets
+ propagated as expected. */
if (*changed_p)
recompute_tree_invariant_for_addr_expr (expr);
return NULL_TREE;
- case POINTER_PLUS_EXPR:
- t = walk_tree (&TREE_OPERAND (expr, 0), fold_stmt_r, data, NULL);
- if (t)
- return t;
- t = walk_tree (&TREE_OPERAND (expr, 1), fold_stmt_r, data, NULL);
- if (t)
- return t;
- *walk_subtrees = 0;
-
- t = maybe_fold_stmt_addition (expr);
- break;
-
case COMPONENT_REF:
t = walk_tree (&TREE_OPERAND (expr, 0), fold_stmt_r, data, NULL);
if (t)
t = maybe_fold_tmr (expr);
break;
+ case POINTER_PLUS_EXPR:
+ t = walk_tree (&TREE_OPERAND (expr, 0), fold_stmt_r, data, NULL);
+ if (t)
+ return t;
+ t = walk_tree (&TREE_OPERAND (expr, 1), fold_stmt_r, data, NULL);
+ if (t)
+ return t;
+ *walk_subtrees = 0;
+
+ t = maybe_fold_stmt_addition (TREE_TYPE (expr),
+ TREE_OPERAND (expr, 0),
+ TREE_OPERAND (expr, 1));
+ break;
+
case COND_EXPR:
if (COMPARISON_CLASS_P (TREE_OPERAND (expr, 0)))
{
tem = fold_binary (TREE_CODE (op0), TREE_TYPE (op0),
TREE_OPERAND (op0, 0),
TREE_OPERAND (op0, 1));
- set = tem && set_rhs (expr_p, tem);
+ /* This is actually a conditional expression, not a GIMPLE
+ conditional statement, however, the valid_gimple_rhs_p
+ test still applies. */
+ set = tem && is_gimple_condexpr (tem) && valid_gimple_rhs_p (tem);
fold_undefer_overflow_warnings (set, fold_stmt_r_data->stmt, 0);
if (set)
{
- t = *expr_p;
+ COND_EXPR_COND (expr) = tem;
+ t = expr;
break;
}
}
if (t)
{
- /* Preserve volatileness of the original expression. */
- TREE_THIS_VOLATILE (t) = volatile_p;
+ /* Preserve volatileness of the original expression.
+ We can end up with a plain decl here which is shared
+ and we shouldn't mess with its flags. */
+ if (!SSA_VAR_P (t))
+ TREE_THIS_VOLATILE (t) = volatile_p;
*expr_p = t;
*changed_p = true;
}
return NULL_TREE;
}
-
/* Return the string length, maximum string length or maximum value of
ARG in LENGTH.
If ARG is an SSA name variable, follow its use-def chains. If LENGTH
static bool
get_maxval_strlen (tree arg, tree *length, bitmap visited, int type)
{
- tree var, def_stmt, val;
+ tree var, val;
+ gimple def_stmt;
if (TREE_CODE (arg) != SSA_NAME)
{
if (TREE_CODE (arg) == COND_EXPR)
return get_maxval_strlen (COND_EXPR_THEN (arg), length, visited, type)
&& get_maxval_strlen (COND_EXPR_ELSE (arg), length, visited, type);
+ /* We can end up with &(*iftmp_1)[0] here as well, so handle it. */
+ else if (TREE_CODE (arg) == ADDR_EXPR
+ && TREE_CODE (TREE_OPERAND (arg, 0)) == ARRAY_REF
+ && integer_zerop (TREE_OPERAND (TREE_OPERAND (arg, 0), 1)))
+ {
+ tree aop0 = TREE_OPERAND (TREE_OPERAND (arg, 0), 0);
+ if (TREE_CODE (aop0) == INDIRECT_REF
+ && TREE_CODE (TREE_OPERAND (aop0, 0)) == SSA_NAME)
+ return get_maxval_strlen (TREE_OPERAND (aop0, 0),
+ length, visited, type);
+ }
if (type == 2)
{
var = arg;
def_stmt = SSA_NAME_DEF_STMT (var);
- switch (TREE_CODE (def_stmt))
- {
- case GIMPLE_MODIFY_STMT:
- {
- tree rhs;
-
- /* The RHS of the statement defining VAR must either have a
- constant length or come from another SSA_NAME with a constant
- length. */
- rhs = GIMPLE_STMT_OPERAND (def_stmt, 1);
- STRIP_NOPS (rhs);
- return get_maxval_strlen (rhs, length, visited, type);
- }
-
- case PHI_NODE:
+ switch (gimple_code (def_stmt))
+ {
+ case GIMPLE_ASSIGN:
+ /* The RHS of the statement defining VAR must either have a
+ constant length or come from another SSA_NAME with a constant
+ length. */
+ if (gimple_assign_single_p (def_stmt)
+ || gimple_assign_unary_nop_p (def_stmt))
+ {
+ tree rhs = gimple_assign_rhs1 (def_stmt);
+ return get_maxval_strlen (rhs, length, visited, type);
+ }
+ return false;
+
+ case GIMPLE_PHI:
{
/* All the arguments of the PHI node must have the same constant
length. */
- int i;
-
- for (i = 0; i < PHI_NUM_ARGS (def_stmt); i++)
- {
- tree arg = PHI_ARG_DEF (def_stmt, i);
-
- /* If this PHI has itself as an argument, we cannot
- determine the string length of this argument. However,
- if we can find a constant string length for the other
- PHI args then we can still be sure that this is a
- constant string length. So be optimistic and just
- continue with the next argument. */
- if (arg == PHI_RESULT (def_stmt))
- continue;
-
- if (!get_maxval_strlen (arg, length, visited, type))
- return false;
- }
-
- return true;
- }
+ unsigned i;
+
+ for (i = 0; i < gimple_phi_num_args (def_stmt); i++)
+ {
+ tree arg = gimple_phi_arg (def_stmt, i)->def;
+
+ /* If this PHI has itself as an argument, we cannot
+ determine the string length of this argument. However,
+ if we can find a constant string length for the other
+ PHI args then we can still be sure that this is a
+ constant string length. So be optimistic and just
+ continue with the next argument. */
+ if (arg == gimple_phi_result (def_stmt))
+ continue;
+
+ if (!get_maxval_strlen (arg, length, visited, type))
+ return false;
+ }
+ }
+ return true;
default:
- break;
+ return false;
}
-
-
- return false;
}
-/* Fold builtin call FN in statement STMT. If it cannot be folded into a
- constant, return NULL_TREE. Otherwise, return its constant value. */
+/* Fold builtin call in statement STMT. Returns a simplified tree.
+ We may return a non-constant expression, including another call
+ to a different function and with different arguments, e.g.,
+ substituting memcpy for strcpy when the string length is known.
+ Note that some builtins expand into inline code that may not
+ be valid in GIMPLE. Callers must take care. */
static tree
-ccp_fold_builtin (tree stmt, tree fn)
+ccp_fold_builtin (gimple stmt)
{
tree result, val[3];
tree callee, a;
- int arg_mask, i, type;
+ int arg_idx, type;
bitmap visited;
bool ignore;
- call_expr_arg_iterator iter;
int nargs;
- ignore = TREE_CODE (stmt) != GIMPLE_MODIFY_STMT;
+ gcc_assert (is_gimple_call (stmt));
+
+ ignore = (gimple_call_lhs (stmt) == NULL);
/* First try the generic builtin folder. If that succeeds, return the
result directly. */
- result = fold_call_expr (fn, ignore);
+ result = fold_call_stmt (stmt, ignore);
if (result)
{
if (ignore)
}
/* Ignore MD builtins. */
- callee = get_callee_fndecl (fn);
+ callee = gimple_call_fndecl (stmt);
if (DECL_BUILT_IN_CLASS (callee) == BUILT_IN_MD)
return NULL_TREE;
/* If the builtin could not be folded, and it has no argument list,
we're done. */
- nargs = call_expr_nargs (fn);
+ nargs = gimple_call_num_args (stmt);
if (nargs == 0)
return NULL_TREE;
case BUILT_IN_STRLEN:
case BUILT_IN_FPUTS:
case BUILT_IN_FPUTS_UNLOCKED:
- arg_mask = 1;
+ arg_idx = 0;
type = 0;
break;
case BUILT_IN_STRCPY:
case BUILT_IN_STRNCPY:
- arg_mask = 2;
+ arg_idx = 1;
type = 0;
break;
case BUILT_IN_MEMCPY_CHK:
case BUILT_IN_MEMMOVE_CHK:
case BUILT_IN_MEMSET_CHK:
case BUILT_IN_STRNCPY_CHK:
- arg_mask = 4;
+ arg_idx = 2;
type = 2;
break;
case BUILT_IN_STRCPY_CHK:
case BUILT_IN_STPCPY_CHK:
- arg_mask = 2;
+ arg_idx = 1;
type = 1;
break;
case BUILT_IN_SNPRINTF_CHK:
case BUILT_IN_VSNPRINTF_CHK:
- arg_mask = 2;
+ arg_idx = 1;
type = 2;
break;
default:
return NULL_TREE;
}
+ if (arg_idx >= nargs)
+ return NULL_TREE;
+
/* Try to use the dataflow information gathered by the CCP process. */
visited = BITMAP_ALLOC (NULL);
+ bitmap_clear (visited);
memset (val, 0, sizeof (val));
- init_call_expr_arg_iterator (fn, &iter);
- for (i = 0; arg_mask; i++, arg_mask >>= 1)
- {
- a = next_call_expr_arg (&iter);
- if (arg_mask & 1)
- {
- bitmap_clear (visited);
- if (!get_maxval_strlen (a, &val[i], visited, type))
- val[i] = NULL_TREE;
- }
- }
+ a = gimple_call_arg (stmt, arg_idx);
+ if (!get_maxval_strlen (a, &val[arg_idx], visited, type))
+ val[arg_idx] = NULL_TREE;
BITMAP_FREE (visited);
switch (DECL_FUNCTION_CODE (callee))
{
case BUILT_IN_STRLEN:
- if (val[0])
+ if (val[0] && nargs == 1)
{
- tree new_val = fold_convert (TREE_TYPE (fn), val[0]);
+ tree new_val =
+ fold_convert (TREE_TYPE (gimple_call_lhs (stmt)), val[0]);
/* If the result is not a valid gimple value, or not a cast
of a valid gimple value, then we can not use the result. */
case BUILT_IN_STRCPY:
if (val[1] && is_gimple_val (val[1]) && nargs == 2)
result = fold_builtin_strcpy (callee,
- CALL_EXPR_ARG (fn, 0),
- CALL_EXPR_ARG (fn, 1),
+ gimple_call_arg (stmt, 0),
+ gimple_call_arg (stmt, 1),
val[1]);
break;
case BUILT_IN_STRNCPY:
if (val[1] && is_gimple_val (val[1]) && nargs == 3)
result = fold_builtin_strncpy (callee,
- CALL_EXPR_ARG (fn, 0),
- CALL_EXPR_ARG (fn, 1),
- CALL_EXPR_ARG (fn, 2),
+ gimple_call_arg (stmt, 0),
+ gimple_call_arg (stmt, 1),
+ gimple_call_arg (stmt, 2),
val[1]);
break;
case BUILT_IN_FPUTS:
- result = fold_builtin_fputs (CALL_EXPR_ARG (fn, 0),
- CALL_EXPR_ARG (fn, 1),
- TREE_CODE (stmt) != GIMPLE_MODIFY_STMT, 0,
- val[0]);
+ if (nargs == 2)
+ result = fold_builtin_fputs (gimple_call_arg (stmt, 0),
+ gimple_call_arg (stmt, 1),
+ ignore, false, val[0]);
break;
case BUILT_IN_FPUTS_UNLOCKED:
- result = fold_builtin_fputs (CALL_EXPR_ARG (fn, 0),
- CALL_EXPR_ARG (fn, 1),
- TREE_CODE (stmt) != GIMPLE_MODIFY_STMT, 1,
- val[0]);
+ if (nargs == 2)
+ result = fold_builtin_fputs (gimple_call_arg (stmt, 0),
+ gimple_call_arg (stmt, 1),
+ ignore, true, val[0]);
break;
case BUILT_IN_MEMCPY_CHK:
case BUILT_IN_MEMPCPY_CHK:
case BUILT_IN_MEMMOVE_CHK:
case BUILT_IN_MEMSET_CHK:
- if (val[2] && is_gimple_val (val[2]))
+ if (val[2] && is_gimple_val (val[2]) && nargs == 4)
result = fold_builtin_memory_chk (callee,
- CALL_EXPR_ARG (fn, 0),
- CALL_EXPR_ARG (fn, 1),
- CALL_EXPR_ARG (fn, 2),
- CALL_EXPR_ARG (fn, 3),
+ gimple_call_arg (stmt, 0),
+ gimple_call_arg (stmt, 1),
+ gimple_call_arg (stmt, 2),
+ gimple_call_arg (stmt, 3),
val[2], ignore,
DECL_FUNCTION_CODE (callee));
break;
case BUILT_IN_STRCPY_CHK:
case BUILT_IN_STPCPY_CHK:
- if (val[1] && is_gimple_val (val[1]))
+ if (val[1] && is_gimple_val (val[1]) && nargs == 3)
result = fold_builtin_stxcpy_chk (callee,
- CALL_EXPR_ARG (fn, 0),
- CALL_EXPR_ARG (fn, 1),
- CALL_EXPR_ARG (fn, 2),
+ gimple_call_arg (stmt, 0),
+ gimple_call_arg (stmt, 1),
+ gimple_call_arg (stmt, 2),
val[1], ignore,
DECL_FUNCTION_CODE (callee));
break;
case BUILT_IN_STRNCPY_CHK:
- if (val[2] && is_gimple_val (val[2]))
- result = fold_builtin_strncpy_chk (CALL_EXPR_ARG (fn, 0),
- CALL_EXPR_ARG (fn, 1),
- CALL_EXPR_ARG (fn, 2),
- CALL_EXPR_ARG (fn, 3),
+ if (val[2] && is_gimple_val (val[2]) && nargs == 4)
+ result = fold_builtin_strncpy_chk (gimple_call_arg (stmt, 0),
+ gimple_call_arg (stmt, 1),
+ gimple_call_arg (stmt, 2),
+ gimple_call_arg (stmt, 3),
val[2]);
break;
case BUILT_IN_SNPRINTF_CHK:
case BUILT_IN_VSNPRINTF_CHK:
if (val[1] && is_gimple_val (val[1]))
- result = fold_builtin_snprintf_chk (fn, val[1],
- DECL_FUNCTION_CODE (callee));
+ result = gimple_fold_builtin_snprintf_chk (stmt, val[1],
+ DECL_FUNCTION_CODE (callee));
break;
default:
return result;
}
+/* Attempt to fold an assignment statement pointed-to by SI. Returns a
+ replacement rhs for the statement or NULL_TREE if no simplification
+ could be made. It is assumed that the operands have been previously
+ folded. */
+
+static tree
+fold_gimple_assign (gimple_stmt_iterator *si)
+{
+ gimple stmt = gsi_stmt (*si);
+ enum tree_code subcode = gimple_assign_rhs_code (stmt);
-/* Fold the statement pointed to by STMT_P. In some cases, this function may
+ tree result = NULL;
+
+ switch (get_gimple_rhs_class (subcode))
+ {
+ case GIMPLE_SINGLE_RHS:
+ {
+ tree rhs = gimple_assign_rhs1 (stmt);
+
+ /* Try to fold a conditional expression. */
+ if (TREE_CODE (rhs) == COND_EXPR)
+ {
+ tree temp = fold (COND_EXPR_COND (rhs));
+ if (temp != COND_EXPR_COND (rhs))
+ result = fold_build3 (COND_EXPR, TREE_TYPE (rhs), temp,
+ COND_EXPR_THEN (rhs), COND_EXPR_ELSE (rhs));
+ }
+
+ /* If we couldn't fold the RHS, hand over to the generic
+ fold routines. */
+ if (result == NULL_TREE)
+ result = fold (rhs);
+
+ /* Strip away useless type conversions. Both the NON_LVALUE_EXPR
+ that may have been added by fold, and "useless" type
+ conversions that might now be apparent due to propagation. */
+ STRIP_USELESS_TYPE_CONVERSION (result);
+
+ if (result != rhs && valid_gimple_rhs_p (result))
+ return result;
+ else
+ /* It is possible that fold_stmt_r simplified the RHS.
+ Make sure that the subcode of this statement still
+ reflects the principal operator of the rhs operand. */
+ return rhs;
+ }
+ break;
+
+ case GIMPLE_UNARY_RHS:
+ {
+ tree rhs = gimple_assign_rhs1 (stmt);
+
+ result = fold_unary (subcode, gimple_expr_type (stmt), rhs);
+ if (result)
+ {
+ /* If the operation was a conversion do _not_ mark a
+ resulting constant with TREE_OVERFLOW if the original
+ constant was not. These conversions have implementation
+ defined behavior and retaining the TREE_OVERFLOW flag
+ here would confuse later passes such as VRP. */
+ if (CONVERT_EXPR_CODE_P (subcode)
+ && TREE_CODE (result) == INTEGER_CST
+ && TREE_CODE (rhs) == INTEGER_CST)
+ TREE_OVERFLOW (result) = TREE_OVERFLOW (rhs);
+
+ STRIP_USELESS_TYPE_CONVERSION (result);
+ if (valid_gimple_rhs_p (result))
+ return result;
+ }
+ else if (CONVERT_EXPR_CODE_P (subcode)
+ && POINTER_TYPE_P (gimple_expr_type (stmt))
+ && POINTER_TYPE_P (TREE_TYPE (gimple_assign_rhs1 (stmt))))
+ {
+ tree type = gimple_expr_type (stmt);
+ tree t = maybe_fold_offset_to_address (gimple_assign_rhs1 (stmt),
+ integer_zero_node, type);
+ if (t)
+ return t;
+ }
+ }
+ break;
+
+ case GIMPLE_BINARY_RHS:
+ /* Try to fold pointer addition. */
+ if (gimple_assign_rhs_code (stmt) == POINTER_PLUS_EXPR)
+ {
+ tree type = TREE_TYPE (gimple_assign_rhs1 (stmt));
+ if (TREE_CODE (TREE_TYPE (type)) == ARRAY_TYPE)
+ {
+ type = build_pointer_type (TREE_TYPE (TREE_TYPE (type)));
+ if (!useless_type_conversion_p
+ (TREE_TYPE (gimple_assign_lhs (stmt)), type))
+ type = TREE_TYPE (gimple_assign_rhs1 (stmt));
+ }
+ result = maybe_fold_stmt_addition (type,
+ gimple_assign_rhs1 (stmt),
+ gimple_assign_rhs2 (stmt));
+ }
+
+ if (!result)
+ result = fold_binary (subcode,
+ TREE_TYPE (gimple_assign_lhs (stmt)),
+ gimple_assign_rhs1 (stmt),
+ gimple_assign_rhs2 (stmt));
+
+ if (result)
+ {
+ STRIP_USELESS_TYPE_CONVERSION (result);
+ if (valid_gimple_rhs_p (result))
+ return result;
+
+ /* Fold might have produced non-GIMPLE, so if we trust it blindly
+ we lose canonicalization opportunities. Do not go again
+ through fold here though, or the same non-GIMPLE will be
+ produced. */
+ if (commutative_tree_code (subcode)
+ && tree_swap_operands_p (gimple_assign_rhs1 (stmt),
+ gimple_assign_rhs2 (stmt), false))
+ return build2 (subcode, TREE_TYPE (gimple_assign_lhs (stmt)),
+ gimple_assign_rhs2 (stmt),
+ gimple_assign_rhs1 (stmt));
+ }
+ break;
+
+ case GIMPLE_INVALID_RHS:
+ gcc_unreachable ();
+ }
+
+ return NULL_TREE;
+}
+
+/* Attempt to fold a conditional statement. Return true if any changes were
+ made. We only attempt to fold the condition expression, and do not perform
+ any transformation that would require alteration of the cfg. It is
+ assumed that the operands have been previously folded. */
+
+static bool
+fold_gimple_cond (gimple stmt)
+{
+ tree result = fold_binary (gimple_cond_code (stmt),
+ boolean_type_node,
+ gimple_cond_lhs (stmt),
+ gimple_cond_rhs (stmt));
+
+ if (result)
+ {
+ STRIP_USELESS_TYPE_CONVERSION (result);
+ if (is_gimple_condexpr (result) && valid_gimple_rhs_p (result))
+ {
+ gimple_cond_set_condition_from_tree (stmt, result);
+ return true;
+ }
+ }
+
+ return false;
+}
+
+
+/* Attempt to fold a call statement referenced by the statement iterator GSI.
+ The statement may be replaced by another statement, e.g., if the call
+ simplifies to a constant value. Return true if any changes were made.
+ It is assumed that the operands have been previously folded. */
+
+static bool
+fold_gimple_call (gimple_stmt_iterator *gsi)
+{
+ gimple stmt = gsi_stmt (*gsi);
+
+ tree callee = gimple_call_fndecl (stmt);
+
+ /* Check for builtins that CCP can handle using information not
+ available in the generic fold routines. */
+ if (callee && DECL_BUILT_IN (callee))
+ {
+ tree result = ccp_fold_builtin (stmt);
+
+ if (result)
+ return update_call_from_tree (gsi, result);
+ }
+ else
+ {
+ /* Check for resolvable OBJ_TYPE_REF. The only sorts we can resolve
+ here are when we've propagated the address of a decl into the
+ object slot. */
+ /* ??? Should perhaps do this in fold proper. However, doing it
+ there requires that we create a new CALL_EXPR, and that requires
+ copying EH region info to the new node. Easier to just do it
+ here where we can just smash the call operand. */
+ /* ??? Is there a good reason not to do this in fold_stmt_inplace? */
+ callee = gimple_call_fn (stmt);
+ if (TREE_CODE (callee) == OBJ_TYPE_REF
+ && lang_hooks.fold_obj_type_ref
+ && TREE_CODE (OBJ_TYPE_REF_OBJECT (callee)) == ADDR_EXPR
+ && DECL_P (TREE_OPERAND
+ (OBJ_TYPE_REF_OBJECT (callee), 0)))
+ {
+ tree t;
+
+ /* ??? Caution: Broken ADDR_EXPR semantics means that
+ looking at the type of the operand of the addr_expr
+ can yield an array type. See silly exception in
+ check_pointer_types_r. */
+ t = TREE_TYPE (TREE_TYPE (OBJ_TYPE_REF_OBJECT (callee)));
+ t = lang_hooks.fold_obj_type_ref (callee, t);
+ if (t)
+ {
+ gimple_call_set_fn (stmt, t);
+ return true;
+ }
+ }
+ }
+
+ return false;
+}
+
+/* Fold the statement pointed to by GSI. In some cases, this function may
replace the whole statement with a new one. Returns true iff folding
makes any changes. */
bool
-fold_stmt (tree *stmt_p)
+fold_stmt (gimple_stmt_iterator *gsi)
{
- tree rhs, result, stmt;
+ tree res;
struct fold_stmt_r_data fold_stmt_r_data;
+ struct walk_stmt_info wi;
+
bool changed = false;
bool inside_addr_expr = false;
- stmt = *stmt_p;
+ gimple stmt = gsi_stmt (*gsi);
fold_stmt_r_data.stmt = stmt;
fold_stmt_r_data.changed_p = &changed;
fold_stmt_r_data.inside_addr_expr_p = &inside_addr_expr;
- /* If we replaced constants and the statement makes pointer dereferences,
- then we may need to fold instances of *&VAR into VAR, etc. */
- if (walk_tree (stmt_p, fold_stmt_r, &fold_stmt_r_data, NULL))
- {
- *stmt_p = build_call_expr (implicit_built_in_decls[BUILT_IN_TRAP], 0);
- return true;
- }
+ memset (&wi, 0, sizeof (wi));
+ wi.info = &fold_stmt_r_data;
- rhs = get_rhs (stmt);
- if (!rhs)
- return changed;
- result = NULL_TREE;
+ /* Fold the individual operands.
+ For example, fold instances of *&VAR into VAR, etc. */
+ res = walk_gimple_op (stmt, fold_stmt_r, &wi);
+ gcc_assert (!res);
- if (TREE_CODE (rhs) == CALL_EXPR)
+ /* Fold the main computation performed by the statement. */
+ switch (gimple_code (stmt))
{
- tree callee;
-
- /* Check for builtins that CCP can handle using information not
- available in the generic fold routines. */
- callee = get_callee_fndecl (rhs);
- if (callee && DECL_BUILT_IN (callee))
- result = ccp_fold_builtin (stmt, rhs);
- else
- {
- /* Check for resolvable OBJ_TYPE_REF. The only sorts we can resolve
- here are when we've propagated the address of a decl into the
- object slot. */
- /* ??? Should perhaps do this in fold proper. However, doing it
- there requires that we create a new CALL_EXPR, and that requires
- copying EH region info to the new node. Easier to just do it
- here where we can just smash the call operand. Also
- CALL_EXPR_RETURN_SLOT_OPT needs to be handled correctly and
- copied, fold_call_expr does not have not information. */
- callee = CALL_EXPR_FN (rhs);
- if (TREE_CODE (callee) == OBJ_TYPE_REF
- && lang_hooks.fold_obj_type_ref
- && TREE_CODE (OBJ_TYPE_REF_OBJECT (callee)) == ADDR_EXPR
- && DECL_P (TREE_OPERAND
- (OBJ_TYPE_REF_OBJECT (callee), 0)))
- {
- tree t;
-
- /* ??? Caution: Broken ADDR_EXPR semantics means that
- looking at the type of the operand of the addr_expr
- can yield an array type. See silly exception in
- check_pointer_types_r. */
+ case GIMPLE_ASSIGN:
+ {
+ tree new_rhs = fold_gimple_assign (gsi);
+ if (new_rhs != NULL_TREE)
+ {
+ gimple_assign_set_rhs_from_tree (gsi, new_rhs);
+ changed = true;
+ }
+ stmt = gsi_stmt (*gsi);
+ break;
+ }
+ case GIMPLE_COND:
+ changed |= fold_gimple_cond (stmt);
+ break;
+ case GIMPLE_CALL:
+ /* The entire statement may be replaced in this case. */
+ changed |= fold_gimple_call (gsi);
+ break;
- t = TREE_TYPE (TREE_TYPE (OBJ_TYPE_REF_OBJECT (callee)));
- t = lang_hooks.fold_obj_type_ref (callee, t);
- if (t)
- {
- CALL_EXPR_FN (rhs) = t;
- changed = true;
- }
- }
- }
- }
- else if (TREE_CODE (rhs) == COND_EXPR)
- {
- tree temp = fold (COND_EXPR_COND (rhs));
- if (temp != COND_EXPR_COND (rhs))
- result = fold_build3 (COND_EXPR, TREE_TYPE (rhs), temp,
- COND_EXPR_THEN (rhs), COND_EXPR_ELSE (rhs));
+ default:
+ return changed;
+ break;
}
- /* If we couldn't fold the RHS, hand over to the generic fold routines. */
- if (result == NULL_TREE)
- result = fold (rhs);
-
- /* Strip away useless type conversions. Both the NON_LVALUE_EXPR that
- may have been added by fold, and "useless" type conversions that might
- now be apparent due to propagation. */
- STRIP_USELESS_TYPE_CONVERSION (result);
-
- if (result != rhs)
- changed |= set_rhs (stmt_p, result);
-
return changed;
}
/* Perform the minimal folding on statement STMT. Only operations like
*&x created by constant propagation are handled. The statement cannot
- be replaced with a new one. */
+ be replaced with a new one. Return true if the statement was
+ changed, false otherwise. */
bool
-fold_stmt_inplace (tree stmt)
+fold_stmt_inplace (gimple stmt)
{
- tree old_stmt = stmt, rhs, new_rhs;
+ tree res;
struct fold_stmt_r_data fold_stmt_r_data;
+ struct walk_stmt_info wi;
+ gimple_stmt_iterator si;
+
bool changed = false;
bool inside_addr_expr = false;
fold_stmt_r_data.changed_p = &changed;
fold_stmt_r_data.inside_addr_expr_p = &inside_addr_expr;
- walk_tree (&stmt, fold_stmt_r, &fold_stmt_r_data, NULL);
- gcc_assert (stmt == old_stmt);
+ memset (&wi, 0, sizeof (wi));
+ wi.info = &fold_stmt_r_data;
- rhs = get_rhs (stmt);
- if (!rhs || rhs == stmt)
- return changed;
+ /* Fold the individual operands.
+ For example, fold instances of *&VAR into VAR, etc.
- new_rhs = fold (rhs);
- STRIP_USELESS_TYPE_CONVERSION (new_rhs);
- if (new_rhs == rhs)
- return changed;
+ It appears that, at one time, maybe_fold_stmt_indirect
+ would cause the walk to return non-null in order to
+ signal that the entire statement should be replaced with
+ a call to _builtin_trap. This functionality is currently
+ disabled, as noted in a FIXME, and cannot be supported here. */
+ res = walk_gimple_op (stmt, fold_stmt_r, &wi);
+ gcc_assert (!res);
- changed |= set_rhs (&stmt, new_rhs);
- gcc_assert (stmt == old_stmt);
+ /* Fold the main computation performed by the statement. */
+ switch (gimple_code (stmt))
+ {
+ case GIMPLE_ASSIGN:
+ {
+ unsigned old_num_ops;
+ tree new_rhs;
+ old_num_ops = gimple_num_ops (stmt);
+ si = gsi_for_stmt (stmt);
+ new_rhs = fold_gimple_assign (&si);
+ if (new_rhs != NULL_TREE
+ && get_gimple_rhs_num_ops (TREE_CODE (new_rhs)) < old_num_ops)
+ {
+ gimple_assign_set_rhs_from_tree (&si, new_rhs);
+ changed = true;
+ }
+ gcc_assert (gsi_stmt (si) == stmt);
+ break;
+ }
+ case GIMPLE_COND:
+ changed |= fold_gimple_cond (stmt);
+ break;
+
+ default:
+ break;
+ }
return changed;
}
-\f
+
/* Try to optimize out __builtin_stack_restore. Optimize it out
if there is another __builtin_stack_restore in the same basic
block and no calls or ASM_EXPRs are in between, or if this block's
ASM_EXPRs after this __builtin_stack_restore. */
static tree
-optimize_stack_restore (basic_block bb, tree call, block_stmt_iterator i)
+optimize_stack_restore (gimple_stmt_iterator i)
{
- tree stack_save, stmt, callee;
+ tree callee, rhs;
+ gimple stmt, stack_save;
+ gimple_stmt_iterator stack_save_gsi;
- if (TREE_CODE (call) != CALL_EXPR
- || call_expr_nargs (call) != 1
- || TREE_CODE (CALL_EXPR_ARG (call, 0)) != SSA_NAME
- || !POINTER_TYPE_P (TREE_TYPE (CALL_EXPR_ARG (call, 0))))
+ basic_block bb = gsi_bb (i);
+ gimple call = gsi_stmt (i);
+
+ if (gimple_code (call) != GIMPLE_CALL
+ || gimple_call_num_args (call) != 1
+ || TREE_CODE (gimple_call_arg (call, 0)) != SSA_NAME
+ || !POINTER_TYPE_P (TREE_TYPE (gimple_call_arg (call, 0))))
return NULL_TREE;
- for (bsi_next (&i); !bsi_end_p (i); bsi_next (&i))
+ for (gsi_next (&i); !gsi_end_p (i); gsi_next (&i))
{
- tree call;
-
- stmt = bsi_stmt (i);
- if (TREE_CODE (stmt) == ASM_EXPR)
+ stmt = gsi_stmt (i);
+ if (gimple_code (stmt) == GIMPLE_ASM)
return NULL_TREE;
- call = get_call_expr_in (stmt);
- if (call == NULL)
+ if (gimple_code (stmt) != GIMPLE_CALL)
continue;
- callee = get_callee_fndecl (call);
+ callee = gimple_call_fndecl (stmt);
if (!callee || DECL_BUILT_IN_CLASS (callee) != BUILT_IN_NORMAL)
return NULL_TREE;
break;
}
- if (bsi_end_p (i)
+ if (gsi_end_p (i)
&& (! single_succ_p (bb)
|| single_succ_edge (bb)->dest != EXIT_BLOCK_PTR))
return NULL_TREE;
- stack_save = SSA_NAME_DEF_STMT (CALL_EXPR_ARG (call, 0));
- if (TREE_CODE (stack_save) != GIMPLE_MODIFY_STMT
- || GIMPLE_STMT_OPERAND (stack_save, 0) != CALL_EXPR_ARG (call, 0)
- || TREE_CODE (GIMPLE_STMT_OPERAND (stack_save, 1)) != CALL_EXPR
- || tree_could_throw_p (stack_save)
- || !has_single_use (CALL_EXPR_ARG (call, 0)))
+ stack_save = SSA_NAME_DEF_STMT (gimple_call_arg (call, 0));
+ if (gimple_code (stack_save) != GIMPLE_CALL
+ || gimple_call_lhs (stack_save) != gimple_call_arg (call, 0)
+ || stmt_could_throw_p (stack_save)
+ || !has_single_use (gimple_call_arg (call, 0)))
return NULL_TREE;
- callee = get_callee_fndecl (GIMPLE_STMT_OPERAND (stack_save, 1));
+ callee = gimple_call_fndecl (stack_save);
if (!callee
|| DECL_BUILT_IN_CLASS (callee) != BUILT_IN_NORMAL
|| DECL_FUNCTION_CODE (callee) != BUILT_IN_STACK_SAVE
- || call_expr_nargs (GIMPLE_STMT_OPERAND (stack_save, 1)) != 0)
+ || gimple_call_num_args (stack_save) != 0)
return NULL_TREE;
- stmt = stack_save;
- push_stmt_changes (&stmt);
- if (!set_rhs (&stmt,
- build_int_cst (TREE_TYPE (CALL_EXPR_ARG (call, 0)), 0)))
+ stack_save_gsi = gsi_for_stmt (stack_save);
+ push_stmt_changes (gsi_stmt_ptr (&stack_save_gsi));
+ rhs = build_int_cst (TREE_TYPE (gimple_call_arg (call, 0)), 0);
+ if (!update_call_from_tree (&stack_save_gsi, rhs))
{
- discard_stmt_changes (&stmt);
+ discard_stmt_changes (gsi_stmt_ptr (&stack_save_gsi));
return NULL_TREE;
}
- gcc_assert (stmt == stack_save);
- pop_stmt_changes (&stmt);
+ pop_stmt_changes (gsi_stmt_ptr (&stack_save_gsi));
+ /* No effect, so the statement will be deleted. */
return integer_zero_node;
}
-\f
+
/* If va_list type is a simple pointer and nothing special is needed,
optimize __builtin_va_start (&ap, 0) into ap = __builtin_next_arg (0),
__builtin_va_end (&ap) out as NOP and __builtin_va_copy into a simple
pointer assignment. */
static tree
-optimize_stdarg_builtin (tree call)
+optimize_stdarg_builtin (gimple call)
{
- tree callee, lhs, rhs;
+ tree callee, lhs, rhs, cfun_va_list;
bool va_list_simple_ptr;
- if (TREE_CODE (call) != CALL_EXPR)
+ if (gimple_code (call) != GIMPLE_CALL)
return NULL_TREE;
- va_list_simple_ptr = POINTER_TYPE_P (va_list_type_node)
- && (TREE_TYPE (va_list_type_node) == void_type_node
- || TREE_TYPE (va_list_type_node) == char_type_node);
+ callee = gimple_call_fndecl (call);
+
+ cfun_va_list = targetm.fn_abi_va_list (callee);
+ va_list_simple_ptr = POINTER_TYPE_P (cfun_va_list)
+ && (TREE_TYPE (cfun_va_list) == void_type_node
+ || TREE_TYPE (cfun_va_list) == char_type_node);
- callee = get_callee_fndecl (call);
switch (DECL_FUNCTION_CODE (callee))
{
case BUILT_IN_VA_START:
if (!va_list_simple_ptr
|| targetm.expand_builtin_va_start != NULL
- || built_in_decls[BUILT_IN_NEXT_ARG] == NULL)
+ || built_in_decls[BUILT_IN_NEXT_ARG] == NULL)
return NULL_TREE;
- if (call_expr_nargs (call) != 2)
+ if (gimple_call_num_args (call) != 2)
return NULL_TREE;
- lhs = CALL_EXPR_ARG (call, 0);
+ lhs = gimple_call_arg (call, 0);
if (!POINTER_TYPE_P (TREE_TYPE (lhs))
|| TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (lhs)))
- != TYPE_MAIN_VARIANT (va_list_type_node))
+ != TYPE_MAIN_VARIANT (cfun_va_list))
return NULL_TREE;
-
+
lhs = build_fold_indirect_ref (lhs);
rhs = build_call_expr (built_in_decls[BUILT_IN_NEXT_ARG],
- 1, integer_zero_node);
+ 1, integer_zero_node);
rhs = fold_convert (TREE_TYPE (lhs), rhs);
return build2 (MODIFY_EXPR, TREE_TYPE (lhs), lhs, rhs);
if (!va_list_simple_ptr)
return NULL_TREE;
- if (call_expr_nargs (call) != 2)
+ if (gimple_call_num_args (call) != 2)
return NULL_TREE;
- lhs = CALL_EXPR_ARG (call, 0);
+ lhs = gimple_call_arg (call, 0);
if (!POINTER_TYPE_P (TREE_TYPE (lhs))
|| TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (lhs)))
- != TYPE_MAIN_VARIANT (va_list_type_node))
+ != TYPE_MAIN_VARIANT (cfun_va_list))
return NULL_TREE;
lhs = build_fold_indirect_ref (lhs);
- rhs = CALL_EXPR_ARG (call, 1);
+ rhs = gimple_call_arg (call, 1);
if (TYPE_MAIN_VARIANT (TREE_TYPE (rhs))
- != TYPE_MAIN_VARIANT (va_list_type_node))
+ != TYPE_MAIN_VARIANT (cfun_va_list))
return NULL_TREE;
rhs = fold_convert (TREE_TYPE (lhs), rhs);
return build2 (MODIFY_EXPR, TREE_TYPE (lhs), lhs, rhs);
case BUILT_IN_VA_END:
+ /* No effect, so the statement will be deleted. */
return integer_zero_node;
default:
gcc_unreachable ();
}
}
-\f
+
/* Convert EXPR into a GIMPLE value suitable for substitution on the
RHS of an assignment. Insert the necessary statements before
- iterator *SI_P.
- When IGNORE is set, don't worry about the return value. */
+ iterator *SI_P. The statement at *SI_P, which must be a GIMPLE_CALL
+ is replaced. If the call is expected to produces a result, then it
+ is replaced by an assignment of the new RHS to the result variable.
+ If the result is to be ignored, then the call is replaced by a
+ GIMPLE_NOP. */
-static tree
-convert_to_gimple_builtin (block_stmt_iterator *si_p, tree expr, bool ignore)
+static void
+gimplify_and_update_call_from_tree (gimple_stmt_iterator *si_p, tree expr)
{
- tree_stmt_iterator ti;
- tree stmt = bsi_stmt (*si_p);
- tree tmp, stmts = NULL;
+ tree lhs;
+ tree tmp = NULL_TREE; /* Silence warning. */
+ gimple stmt, new_stmt;
+ gimple_stmt_iterator i;
+ gimple_seq stmts = gimple_seq_alloc();
+ struct gimplify_ctx gctx;
- push_gimplify_context ();
- if (ignore)
- {
- tmp = build_empty_stmt ();
- gimplify_and_add (expr, &stmts);
- }
- else
+ stmt = gsi_stmt (*si_p);
+
+ gcc_assert (is_gimple_call (stmt));
+
+ lhs = gimple_call_lhs (stmt);
+
+ push_gimplify_context (&gctx);
+
+ if (lhs == NULL_TREE)
+ gimplify_and_add (expr, &stmts);
+ else
tmp = get_initialized_tmp_var (expr, &stmts, NULL);
+
pop_gimplify_context (NULL);
- if (EXPR_HAS_LOCATION (stmt))
- annotate_all_with_locus (&stmts, EXPR_LOCATION (stmt));
+ if (gimple_has_location (stmt))
+ annotate_all_with_location (stmts, gimple_location (stmt));
/* The replacement can expose previously unreferenced variables. */
- for (ti = tsi_start (stmts); !tsi_end_p (ti); tsi_next (&ti))
+ for (i = gsi_start (stmts); !gsi_end_p (i); gsi_next (&i))
+ {
+ new_stmt = gsi_stmt (i);
+ find_new_referenced_vars (new_stmt);
+ gsi_insert_before (si_p, new_stmt, GSI_NEW_STMT);
+ mark_symbols_for_renaming (new_stmt);
+ gsi_next (si_p);
+ }
+
+ if (lhs == NULL_TREE)
+ new_stmt = gimple_build_nop ();
+ else
{
- tree new_stmt = tsi_stmt (ti);
- find_new_referenced_vars (tsi_stmt_ptr (ti));
- bsi_insert_before (si_p, new_stmt, BSI_NEW_STMT);
- mark_symbols_for_renaming (new_stmt);
- bsi_next (si_p);
+ new_stmt = gimple_build_assign (lhs, tmp);
+ copy_virtual_operands (new_stmt, stmt);
+ move_ssa_defining_stmt_for_defs (new_stmt, stmt);
}
- return tmp;
+ gimple_set_location (new_stmt, gimple_location (stmt));
+ gsi_replace (si_p, new_stmt, false);
}
-
/* A simple pass that attempts to fold all builtin functions. This pass
is run after we've propagated as many constants as we can. */
FOR_EACH_BB (bb)
{
- block_stmt_iterator i;
- for (i = bsi_start (bb); !bsi_end_p (i); )
+ gimple_stmt_iterator i;
+ for (i = gsi_start_bb (bb); !gsi_end_p (i); )
{
- tree *stmtp = bsi_stmt_ptr (i);
- tree old_stmt = *stmtp;
- tree call = get_rhs (*stmtp);
+ gimple stmt, old_stmt;
tree callee, result;
enum built_in_function fcode;
- if (!call || TREE_CODE (call) != CALL_EXPR)
+ stmt = gsi_stmt (i);
+
+ if (gimple_code (stmt) != GIMPLE_CALL)
{
- bsi_next (&i);
+ gsi_next (&i);
continue;
}
- callee = get_callee_fndecl (call);
+ callee = gimple_call_fndecl (stmt);
if (!callee || DECL_BUILT_IN_CLASS (callee) != BUILT_IN_NORMAL)
{
- bsi_next (&i);
+ gsi_next (&i);
continue;
}
fcode = DECL_FUNCTION_CODE (callee);
- result = ccp_fold_builtin (*stmtp, call);
+ result = ccp_fold_builtin (stmt);
+
+ if (result)
+ gimple_remove_stmt_histograms (cfun, stmt);
+
if (!result)
switch (DECL_FUNCTION_CODE (callee))
{
/* Resolve __builtin_constant_p. If it hasn't been
folded to integer_one_node by now, it's fairly
certain that the value simply isn't constant. */
- result = integer_zero_node;
+ result = integer_zero_node;
break;
case BUILT_IN_STACK_RESTORE:
- result = optimize_stack_restore (bb, *stmtp, i);
+ result = optimize_stack_restore (i);
if (result)
break;
- bsi_next (&i);
+ gsi_next (&i);
continue;
case BUILT_IN_VA_START:
case BUILT_IN_VA_END:
case BUILT_IN_VA_COPY:
/* These shouldn't be folded before pass_stdarg. */
- result = optimize_stdarg_builtin (*stmtp);
+ result = optimize_stdarg_builtin (stmt);
if (result)
break;
/* FALLTHRU */
default:
- bsi_next (&i);
+ gsi_next (&i);
continue;
}
if (dump_file && (dump_flags & TDF_DETAILS))
{
fprintf (dump_file, "Simplified\n ");
- print_generic_stmt (dump_file, *stmtp, dump_flags);
+ print_gimple_stmt (dump_file, stmt, 0, dump_flags);
}
- push_stmt_changes (stmtp);
+ old_stmt = stmt;
+ push_stmt_changes (gsi_stmt_ptr (&i));
- if (!set_rhs (stmtp, result))
- {
- result = convert_to_gimple_builtin (&i, result,
- TREE_CODE (old_stmt)
- != GIMPLE_MODIFY_STMT);
- if (result)
- {
- bool ok = set_rhs (stmtp, result);
- gcc_assert (ok);
- todoflags |= TODO_rebuild_alias;
- }
- }
+ if (!update_call_from_tree (&i, result))
+ {
+ gimplify_and_update_call_from_tree (&i, result);
+ todoflags |= TODO_rebuild_alias;
+ }
- pop_stmt_changes (stmtp);
+ stmt = gsi_stmt (i);
+ pop_stmt_changes (gsi_stmt_ptr (&i));
- if (maybe_clean_or_replace_eh_stmt (old_stmt, *stmtp)
- && tree_purge_dead_eh_edges (bb))
+ if (maybe_clean_or_replace_eh_stmt (old_stmt, stmt)
+ && gimple_purge_dead_eh_edges (bb))
cfg_changed = true;
if (dump_file && (dump_flags & TDF_DETAILS))
{
fprintf (dump_file, "to\n ");
- print_generic_stmt (dump_file, *stmtp, dump_flags);
+ print_gimple_stmt (dump_file, stmt, 0, dump_flags);
fprintf (dump_file, "\n");
}
/* Retry the same statement if it changed into another
builtin, there might be new opportunities now. */
- call = get_rhs (*stmtp);
- if (!call || TREE_CODE (call) != CALL_EXPR)
+ if (gimple_code (stmt) != GIMPLE_CALL)
{
- bsi_next (&i);
+ gsi_next (&i);
continue;
}
- callee = get_callee_fndecl (call);
+ callee = gimple_call_fndecl (stmt);
if (!callee
- || DECL_BUILT_IN_CLASS (callee) != BUILT_IN_NORMAL
+ || DECL_BUILT_IN_CLASS (callee) != BUILT_IN_NORMAL
|| DECL_FUNCTION_CODE (callee) == fcode)
- bsi_next (&i);
+ gsi_next (&i);
}
}
}
-struct tree_opt_pass pass_fold_builtins =
+struct gimple_opt_pass pass_fold_builtins =
{
+ {
+ GIMPLE_PASS,
"fab", /* name */
NULL, /* gate */
execute_fold_all_builtins, /* execute */
0, /* todo_flags_start */
TODO_dump_func
| TODO_verify_ssa
- | TODO_update_ssa, /* todo_flags_finish */
- 0 /* letter */
+ | TODO_update_ssa /* todo_flags_finish */
+ }
};
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