tree visit_fun(tree *decl, int *subtrees, void *dummy)
{
(void)subtrees;
(void)dummy;
enum tree_code code = TREE_CODE(*decl);
tree var = NULL_TREE;
if(code == BIND_EXPR)
{
for(var = BIND_EXPR_VARS(*decl); var; var = TREE_CHAIN(var))
{
if(TREE_CODE(var) == VAR_DECL)
{
if(auto_var_in_fn_p(var, current_function_decl) &&
!DECL_ARTIFICIAL(var))
{
if(!DECL_INITIAL(var))
{
tree init_var = walk_tree_without_duplicates(decl, walk_init, var);
if(init_var == NULL_TREE)
{
// don't check classes initialization (too complicated)
if(!(TREE_CODE(TREE_TYPE(var)) == RECORD_TYPE &&
CLASSTYPE_DECLARED_CLASS(TREE_TYPE(var))))
{
WARNING_DECL(*decl, "uninititialized auto var %qD", var);
}
}
}
}
}
}
}
return NULL_TREE;
}
static void
output_gimple_stmt (struct output_block *ob, gimple stmt)
{
unsigned i;
enum gimple_code code;
enum LTO_tags tag;
struct bitpack_d bp;
histogram_value hist;
/* Emit identifying tag. */
code = gimple_code (stmt);
tag = lto_gimple_code_to_tag (code);
streamer_write_record_start (ob, tag);
/* Emit the tuple header. */
bp = bitpack_create (ob->main_stream);
bp_pack_var_len_unsigned (&bp, gimple_num_ops (stmt));
bp_pack_value (&bp, gimple_no_warning_p (stmt), 1);
if (is_gimple_assign (stmt))
bp_pack_value (&bp, gimple_assign_nontemporal_move_p (stmt), 1);
bp_pack_value (&bp, gimple_has_volatile_ops (stmt), 1);
hist = gimple_histogram_value (cfun, stmt);
bp_pack_value (&bp, hist != NULL, 1);
bp_pack_var_len_unsigned (&bp, stmt->gsbase.subcode);
/* Emit location information for the statement. */
stream_output_location (ob, &bp, LOCATION_LOCUS (gimple_location (stmt)));
streamer_write_bitpack (&bp);
/* Emit the lexical block holding STMT. */
stream_write_tree (ob, gimple_block (stmt), true);
/* Emit the operands. */
switch (gimple_code (stmt))
{
case GIMPLE_RESX:
streamer_write_hwi (ob, gimple_resx_region (stmt));
break;
case GIMPLE_EH_MUST_NOT_THROW:
stream_write_tree (ob, gimple_eh_must_not_throw_fndecl (stmt), true);
break;
case GIMPLE_EH_DISPATCH:
streamer_write_hwi (ob, gimple_eh_dispatch_region (stmt));
break;
case GIMPLE_ASM:
streamer_write_uhwi (ob, gimple_asm_ninputs (stmt));
streamer_write_uhwi (ob, gimple_asm_noutputs (stmt));
streamer_write_uhwi (ob, gimple_asm_nclobbers (stmt));
streamer_write_uhwi (ob, gimple_asm_nlabels (stmt));
streamer_write_string (ob, ob->main_stream, gimple_asm_string (stmt),
true);
/* Fallthru */
case GIMPLE_ASSIGN:
case GIMPLE_CALL:
case GIMPLE_RETURN:
case GIMPLE_SWITCH:
case GIMPLE_LABEL:
case GIMPLE_COND:
case GIMPLE_GOTO:
case GIMPLE_DEBUG:
for (i = 0; i < gimple_num_ops (stmt); i++)
{
tree op = gimple_op (stmt, i);
tree *basep = NULL;
/* Wrap all uses of non-automatic variables inside MEM_REFs
so that we do not have to deal with type mismatches on
merged symbols during IL read in. The first operand
of GIMPLE_DEBUG must be a decl, not MEM_REF, though. */
if (op && (i || !is_gimple_debug (stmt)))
{
basep = &op;
while (handled_component_p (*basep))
basep = &TREE_OPERAND (*basep, 0);
if (TREE_CODE (*basep) == VAR_DECL
&& !auto_var_in_fn_p (*basep, current_function_decl)
&& !DECL_REGISTER (*basep))
{
bool volatilep = TREE_THIS_VOLATILE (*basep);
*basep = build2 (MEM_REF, TREE_TYPE (*basep),
build_fold_addr_expr (*basep),
build_int_cst (build_pointer_type
(TREE_TYPE (*basep)), 0));
TREE_THIS_VOLATILE (*basep) = volatilep;
}
else
basep = NULL;
}
stream_write_tree (ob, op, true);
/* Restore the original base if we wrapped it inside a MEM_REF. */
if (basep)
*basep = TREE_OPERAND (TREE_OPERAND (*basep, 0), 0);
}
if (is_gimple_call (stmt))
{
if (gimple_call_internal_p (stmt))
streamer_write_enum (ob->main_stream, internal_fn,
IFN_LAST, gimple_call_internal_fn (stmt));
else
stream_write_tree (ob, gimple_call_fntype (stmt), true);
}
break;
case GIMPLE_NOP:
case GIMPLE_PREDICT:
break;
case GIMPLE_TRANSACTION:
gcc_assert (gimple_transaction_body (stmt) == NULL);
stream_write_tree (ob, gimple_transaction_label (stmt), true);
break;
default:
gcc_unreachable ();
}
if (hist)
stream_out_histogram_value (ob, hist);
}
static void
find_tail_calls (basic_block bb, struct tailcall **ret)
{
tree ass_var = NULL_TREE, ret_var, func, param;
gimple stmt, call = NULL;
gimple_stmt_iterator gsi, agsi;
bool tail_recursion;
struct tailcall *nw;
edge e;
tree m, a;
basic_block abb;
size_t idx;
tree var;
if (!single_succ_p (bb))
return;
for (gsi = gsi_last_bb (bb); !gsi_end_p (gsi); gsi_prev (&gsi))
{
stmt = gsi_stmt (gsi);
/* Ignore labels, returns, clobbers and debug stmts. */
if (gimple_code (stmt) == GIMPLE_LABEL
|| gimple_code (stmt) == GIMPLE_RETURN
|| gimple_clobber_p (stmt)
|| is_gimple_debug (stmt))
continue;
/* Check for a call. */
if (is_gimple_call (stmt))
{
call = stmt;
ass_var = gimple_call_lhs (stmt);
break;
}
/* If the statement references memory or volatile operands, fail. */
if (gimple_references_memory_p (stmt)
|| gimple_has_volatile_ops (stmt))
return;
}
if (gsi_end_p (gsi))
{
edge_iterator ei;
/* Recurse to the predecessors. */
FOR_EACH_EDGE (e, ei, bb->preds)
find_tail_calls (e->src, ret);
return;
}
/* If the LHS of our call is not just a simple register, we can't
transform this into a tail or sibling call. This situation happens,
in (e.g.) "*p = foo()" where foo returns a struct. In this case
we won't have a temporary here, but we need to carry out the side
effect anyway, so tailcall is impossible.
??? In some situations (when the struct is returned in memory via
invisible argument) we could deal with this, e.g. by passing 'p'
itself as that argument to foo, but it's too early to do this here,
and expand_call() will not handle it anyway. If it ever can, then
we need to revisit this here, to allow that situation. */
if (ass_var && !is_gimple_reg (ass_var))
return;
/* We found the call, check whether it is suitable. */
tail_recursion = false;
func = gimple_call_fndecl (call);
if (func
&& !DECL_BUILT_IN (func)
&& recursive_call_p (current_function_decl, func))
{
tree arg;
for (param = DECL_ARGUMENTS (func), idx = 0;
param && idx < gimple_call_num_args (call);
param = DECL_CHAIN (param), idx ++)
{
arg = gimple_call_arg (call, idx);
if (param != arg)
{
/* Make sure there are no problems with copying. The parameter
have a copyable type and the two arguments must have reasonably
equivalent types. The latter requirement could be relaxed if
we emitted a suitable type conversion statement. */
if (!is_gimple_reg_type (TREE_TYPE (param))
|| !useless_type_conversion_p (TREE_TYPE (param),
TREE_TYPE (arg)))
break;
/* The parameter should be a real operand, so that phi node
created for it at the start of the function has the meaning
of copying the value. This test implies is_gimple_reg_type
from the previous condition, however this one could be
relaxed by being more careful with copying the new value
of the parameter (emitting appropriate GIMPLE_ASSIGN and
updating the virtual operands). */
if (!is_gimple_reg (param))
break;
}
}
if (idx == gimple_call_num_args (call) && !param)
tail_recursion = true;
}
/* Make sure the tail invocation of this function does not refer
to local variables. */
FOR_EACH_LOCAL_DECL (cfun, idx, var)
{
if (TREE_CODE (var) != PARM_DECL
&& auto_var_in_fn_p (var, cfun->decl)
&& (ref_maybe_used_by_stmt_p (call, var)
|| call_may_clobber_ref_p (call, var)))
return;
}
/* Now check the statements after the call. None of them has virtual
operands, so they may only depend on the call through its return
value. The return value should also be dependent on each of them,
since we are running after dce. */
m = NULL_TREE;
a = NULL_TREE;
abb = bb;
agsi = gsi;
while (1)
{
tree tmp_a = NULL_TREE;
tree tmp_m = NULL_TREE;
gsi_next (&agsi);
while (gsi_end_p (agsi))
{
ass_var = propagate_through_phis (ass_var, single_succ_edge (abb));
abb = single_succ (abb);
agsi = gsi_start_bb (abb);
}
stmt = gsi_stmt (agsi);
if (gimple_code (stmt) == GIMPLE_LABEL)
continue;
if (gimple_code (stmt) == GIMPLE_RETURN)
break;
if (gimple_clobber_p (stmt))
continue;
if (is_gimple_debug (stmt))
continue;
if (gimple_code (stmt) != GIMPLE_ASSIGN)
return;
/* This is a gimple assign. */
if (! process_assignment (stmt, gsi, &tmp_m, &tmp_a, &ass_var))
return;
if (tmp_a)
{
tree type = TREE_TYPE (tmp_a);
if (a)
a = fold_build2 (PLUS_EXPR, type, fold_convert (type, a), tmp_a);
else
a = tmp_a;
}
if (tmp_m)
{
tree type = TREE_TYPE (tmp_m);
if (m)
m = fold_build2 (MULT_EXPR, type, fold_convert (type, m), tmp_m);
else
m = tmp_m;
if (a)
a = fold_build2 (MULT_EXPR, type, fold_convert (type, a), tmp_m);
}
}
/* See if this is a tail call we can handle. */
ret_var = gimple_return_retval (stmt);
/* We may proceed if there either is no return value, or the return value
is identical to the call's return. */
if (ret_var
&& (ret_var != ass_var))
return;
/* If this is not a tail recursive call, we cannot handle addends or
multiplicands. */
if (!tail_recursion && (m || a))
return;
/* For pointers only allow additions. */
if (m && POINTER_TYPE_P (TREE_TYPE (DECL_RESULT (current_function_decl))))
return;
nw = XNEW (struct tailcall);
nw->call_gsi = gsi;
nw->tail_recursion = tail_recursion;
nw->mult = m;
nw->add = a;
nw->next = *ret;
*ret = nw;
}
