#include "output.h"
#include "timevar.h"
#include "predict.h"
+#include "tree-inline.h"
/* If non-NULL, the address of a language-specific function for
expanding statements. */
variables and labels do not require any RTL generation. */
void (*lang_expand_decl_stmt) PARAMS ((tree));
+static tree find_reachable_label_1 PARAMS ((tree *, int *, void *));
+static tree find_reachable_label PARAMS ((tree));
+static bool expand_unreachable_if_stmt PARAMS ((tree));
+static tree expand_unreachable_stmt PARAMS ((tree, int));
+static void genrtl_do_stmt_1 PARAMS ((tree, tree));
+
/* Create an empty statement tree rooted at T. */
void
{
/* The line-number recorded in the outermost statement in a function
is the line number of the end of the function. */
- STMT_LINENO (stmt) = lineno;
+ STMT_LINENO (stmt) = input_line;
STMT_LINENO_FOR_FN_P (stmt) = 1;
}
}
in the grammar. */
tree
-build_stmt VPARAMS ((enum tree_code code, ...))
+build_stmt (enum tree_code code, ...)
{
tree t;
int length;
int i;
-
- VA_OPEN (p, code);
- VA_FIXEDARG (p, enum tree_code, code);
+ va_list p;
+
+ va_start (p, code);
t = make_node (code);
length = TREE_CODE_LENGTH (code);
- STMT_LINENO (t) = lineno;
+ STMT_LINENO (t) = input_line;
for (i = 0; i < length; i++)
TREE_OPERAND (t, i) = va_arg (p, tree);
- VA_CLOSE (p);
+ va_end (p);
return t;
}
expand_decl (decl);
}
- /* Actually do the initialization. */
- if (stmts_are_full_exprs_p ())
- expand_start_target_temps ();
+ if (DECL_INITIAL (decl))
+ {
+ /* Actually do the initialization. */
+ if (stmts_are_full_exprs_p ())
+ expand_start_target_temps ();
- expand_decl_init (decl);
+ expand_decl_init (decl);
- if (stmts_are_full_exprs_p ())
- expand_end_target_temps ();
+ if (stmts_are_full_exprs_p ())
+ expand_end_target_temps ();
+ }
}
/* Helper for generating the RTL at the beginning of a scope. */
void
genrtl_do_pushlevel ()
{
- emit_line_note (input_filename, lineno);
+ emit_line_note (input_filename, input_line);
clear_last_expr ();
}
if (TREE_CODE (destination) == LABEL_DECL)
TREE_USED (destination) = 1;
- emit_line_note (input_filename, lineno);
+ emit_line_note (input_filename, input_line);
if (TREE_CODE (destination) == LABEL_DECL)
{
{
if (expr != NULL_TREE)
{
- emit_line_note (input_filename, lineno);
+ emit_line_note (input_filename, input_line);
if (stmts_are_full_exprs_p ())
expand_start_target_temps ();
tree t;
{
tree decl;
- emit_line_note (input_filename, lineno);
+ emit_line_note (input_filename, input_line);
decl = DECL_STMT_DECL (t);
/* If this is a declaration for an automatic local
variable, initialize it. Note that we might also see a
tree cond;
genrtl_do_pushlevel ();
cond = expand_cond (IF_COND (t));
- emit_line_note (input_filename, lineno);
+ emit_line_note (input_filename, input_line);
expand_start_cond (cond, 0);
if (THEN_CLAUSE (t))
- expand_stmt (THEN_CLAUSE (t));
+ {
+ tree nextt = THEN_CLAUSE (t);
+
+ if (cond && integer_zerop (cond))
+ nextt = expand_unreachable_stmt (nextt, warn_notreached);
+ expand_stmt (nextt);
+ }
+
if (ELSE_CLAUSE (t))
{
+ tree nextt = ELSE_CLAUSE (t);
expand_start_else ();
- expand_stmt (ELSE_CLAUSE (t));
+ if (cond && integer_nonzerop (cond))
+ nextt = expand_unreachable_stmt (nextt, warn_notreached);
+ expand_stmt (nextt);
}
expand_end_cond ();
}
tree cond = WHILE_COND (t);
emit_nop ();
- emit_line_note (input_filename, lineno);
+ emit_line_note (input_filename, input_line);
expand_start_loop (1);
genrtl_do_pushlevel ();
if (cond && !integer_nonzerop (cond))
{
cond = expand_cond (cond);
- emit_line_note (input_filename, lineno);
+ emit_line_note (input_filename, input_line);
expand_exit_loop_top_cond (0, cond);
genrtl_do_pushlevel ();
}
expand_end_loop ();
}
-/* Generate the RTL for T, which is a DO_STMT. */
+/* Generate the RTL for a DO_STMT with condition COND and loop BODY
+ body. This is reused for expanding unreachable WHILE_STMTS. */
-void
-genrtl_do_stmt (t)
- tree t;
+static void
+genrtl_do_stmt_1 (cond, body)
+ tree cond, body;
{
- tree cond = DO_COND (t);
-
/* Recognize the common special-case of do { ... } while (0) and do
not emit the loop widgetry in this case. In particular this
avoids cluttering the rtl with dummy loop notes, which can affect
if (!cond || integer_zerop (cond))
{
expand_start_null_loop ();
- expand_stmt (DO_BODY (t));
+ expand_stmt (body);
expand_end_null_loop ();
}
else if (integer_nonzerop (cond))
{
emit_nop ();
- emit_line_note (input_filename, lineno);
+ emit_line_note (input_filename, input_line);
expand_start_loop (1);
- expand_stmt (DO_BODY (t));
+ expand_stmt (body);
- emit_line_note (input_filename, lineno);
+ emit_line_note (input_filename, input_line);
expand_end_loop ();
}
else
{
emit_nop ();
- emit_line_note (input_filename, lineno);
+ emit_line_note (input_filename, input_line);
expand_start_loop_continue_elsewhere (1);
- expand_stmt (DO_BODY (t));
+ expand_stmt (body);
expand_loop_continue_here ();
cond = expand_cond (cond);
- emit_line_note (input_filename, lineno);
+ emit_line_note (input_filename, input_line);
expand_exit_loop_if_false (0, cond);
expand_end_loop ();
}
}
+/* Generate the RTL for T, which is a DO_STMT. */
+
+void
+genrtl_do_stmt (t)
+ tree t;
+{
+ genrtl_do_stmt_1 (DO_COND (t), DO_BODY (t));
+}
+
/* Build the node for a return statement and return it. */
tree
expr = RETURN_STMT_EXPR (stmt);
- emit_line_note (input_filename, lineno);
+ emit_line_note (input_filename, input_line);
if (!expr)
expand_null_return ();
else
tree t;
{
tree cond = FOR_COND (t);
- const char *saved_filename;
- int saved_lineno;
+ location_t saved_loc;
if (NEW_FOR_SCOPE_P (t))
genrtl_do_pushlevel ();
/* Expand the initialization. */
emit_nop ();
- emit_line_note (input_filename, lineno);
+ emit_line_note (input_filename, input_line);
if (FOR_EXPR (t))
expand_start_loop_continue_elsewhere (1);
else
/* Save the filename and line number so that we expand the FOR_EXPR
we can reset them back to the saved values. */
- saved_filename = input_filename;
- saved_lineno = lineno;
+ saved_loc = input_location;
/* Expand the condition. */
if (cond && !integer_nonzerop (cond))
{
cond = expand_cond (cond);
- emit_line_note (input_filename, lineno);
+ emit_line_note (input_filename, input_line);
expand_exit_loop_top_cond (0, cond);
genrtl_do_pushlevel ();
}
expand_stmt (FOR_BODY (t));
/* Expand the increment expression. */
- input_filename = saved_filename;
- lineno = saved_lineno;
- emit_line_note (input_filename, lineno);
+ input_location = saved_loc;
+ emit_line_note (input_filename, input_line);
if (FOR_EXPR (t))
{
expand_loop_continue_here ();
void
genrtl_break_stmt ()
{
- emit_line_note (input_filename, lineno);
+ emit_line_note (input_filename, input_line);
if ( ! expand_exit_something ())
error ("break statement not within loop or switch");
}
void
genrtl_continue_stmt ()
{
- emit_line_note (input_filename, lineno);
+ emit_line_note (input_filename, input_line);
if (! expand_continue_loop (0))
error ("continue statement not within a loop");
}
crash. */
cond = boolean_false_node;
- emit_line_note (input_filename, lineno);
+ emit_line_note (input_filename, input_line);
expand_start_case (1, cond, TREE_TYPE (cond), "switch statement");
- expand_stmt (SWITCH_BODY (t));
+ expand_stmt (expand_unreachable_stmt (SWITCH_BODY (t), warn_notreached));
expand_end_case_type (cond, SWITCH_TYPE (t));
}
cv_qualifier = NULL_TREE;
}
- emit_line_note (input_filename, lineno);
+ emit_line_note (input_filename, input_line);
if (asm_input_p)
expand_asm (string, cv_qualifier != NULL_TREE);
else
c_expand_asm_operands (string, output_operands, input_operands,
clobbers, cv_qualifier != NULL_TREE,
- input_filename, lineno);
+ input_filename, input_line);
}
-/* Generate the RTL for a DECL_CLEANUP. */
+/* Generate the RTL for a CLEANUP_STMT. */
void
-genrtl_decl_cleanup (t)
+genrtl_cleanup_stmt (t)
tree t;
{
tree decl = CLEANUP_DECL (t);
tree t;
{
if (!STMT_LINENO_FOR_FN_P (t))
- lineno = STMT_LINENO (t);
+ input_line = STMT_LINENO (t);
current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
}
case RETURN_STMT:
genrtl_return_stmt (t);
- break;
+ t = expand_unreachable_stmt (TREE_CHAIN (t), warn_notreached);
+ goto process_t;
case EXPR_STMT:
genrtl_expr_stmt_value (EXPR_STMT_EXPR (t), TREE_ADDRESSABLE (t),
case BREAK_STMT:
genrtl_break_stmt ();
- break;
+ t = expand_unreachable_stmt (TREE_CHAIN (t), warn_notreached);
+ goto process_t;
case CONTINUE_STMT:
genrtl_continue_stmt ();
- break;
+ t = expand_unreachable_stmt (TREE_CHAIN (t), warn_notreached);
+ goto process_t;
case SWITCH_STMT:
genrtl_switch_stmt (t);
case GOTO_STMT:
/* Emit information for branch prediction. */
if (!GOTO_FAKE_P (t)
- && TREE_CODE (GOTO_DESTINATION (t)) == LABEL_DECL)
+ && TREE_CODE (GOTO_DESTINATION (t)) == LABEL_DECL
+ && flag_guess_branch_prob)
{
rtx note = emit_note (NULL, NOTE_INSN_PREDICTION);
NOTE_PREDICTION (note) = NOTE_PREDICT (PRED_GOTO, NOT_TAKEN);
}
genrtl_goto_stmt (GOTO_DESTINATION (t));
- break;
+ t = expand_unreachable_stmt (TREE_CHAIN (t), warn_notreached);
+ goto process_t;
case ASM_STMT:
genrtl_asm_stmt (ASM_CV_QUAL (t), ASM_STRING (t),
break;
case CLEANUP_STMT:
- genrtl_decl_cleanup (t);
+ genrtl_cleanup_stmt (t);
break;
default:
break;
}
+ /* Go on to the next statement in this scope. */
+ t = TREE_CHAIN (t);
+
+ process_t:
/* Restore saved state. */
current_stmt_tree ()->stmts_are_full_exprs_p
= saved_stmts_are_full_exprs_p;
+ }
+}
+\f
+/* If *TP is a potentially reachable label, return nonzero. */
+
+static tree
+find_reachable_label_1 (tp, walk_subtrees, data)
+ tree *tp;
+ int *walk_subtrees ATTRIBUTE_UNUSED;
+ void *data ATTRIBUTE_UNUSED;
+{
+ switch (TREE_CODE (*tp))
+ {
+ case LABEL_STMT:
+ case CASE_LABEL:
+ return *tp;
- /* Go on to the next statement in this scope. */
+ default:
+ break;
+ }
+ return NULL_TREE;
+}
+
+/* Determine whether expression EXP contains a potentially
+ reachable label. */
+static tree
+find_reachable_label (exp)
+ tree exp;
+{
+ location_t saved_loc = input_location;
+ tree ret = walk_tree (&exp, find_reachable_label_1, NULL, NULL);
+ input_location = saved_loc;
+ return ret;
+}
+
+/* Expand an unreachable if statement, T. This function returns
+ true if the IF_STMT contains a potentially reachable code_label. */
+static bool
+expand_unreachable_if_stmt (t)
+ tree t;
+{
+ tree n;
+
+ if (find_reachable_label (IF_COND (t)) != NULL_TREE)
+ {
+ genrtl_if_stmt (t);
+ return true;
+ }
+
+ if (THEN_CLAUSE (t) && ELSE_CLAUSE (t))
+ {
+ n = expand_unreachable_stmt (THEN_CLAUSE (t), 0);
+
+ if (n != NULL_TREE)
+ {
+ rtx label;
+ expand_stmt (n);
+ label = gen_label_rtx ();
+ emit_jump (label);
+ expand_stmt (expand_unreachable_stmt (ELSE_CLAUSE (t), 0));
+ emit_label (label);
+ return true;
+ }
+ else
+ n = expand_unreachable_stmt (ELSE_CLAUSE (t), 0);
+ }
+ else if (THEN_CLAUSE (t))
+ n = expand_unreachable_stmt (THEN_CLAUSE (t), 0);
+ else if (ELSE_CLAUSE (t))
+ n = expand_unreachable_stmt (ELSE_CLAUSE (t), 0);
+ else
+ n = NULL_TREE;
+
+ expand_stmt (n);
+
+ return n != NULL_TREE;
+}
+
+/* Expand an unreachable statement list. This function skips all
+ statements preceding the first potentially reachable label and
+ then returns the label (or, in same cases, the statement after
+ one containing the label). */
+static tree
+expand_unreachable_stmt (t, warn)
+ tree t;
+ int warn;
+{
+ int saved;
+
+ while (t && t != error_mark_node)
+ {
+ if (warn)
+ switch (TREE_CODE (t))
+ {
+ case BREAK_STMT:
+ case CONTINUE_STMT:
+ case EXPR_STMT:
+ case GOTO_STMT:
+ case IF_STMT:
+ case RETURN_STMT:
+ if (!STMT_LINENO_FOR_FN_P (t))
+ input_line = STMT_LINENO (t);
+ warning("will never be executed");
+ warn = false;
+ break;
+
+ default:
+ break;
+ }
+
+ switch (TREE_CODE (t))
+ {
+ case GOTO_STMT:
+ case CONTINUE_STMT:
+ case BREAK_STMT:
+ break;
+
+ case FILE_STMT:
+ input_filename = FILE_STMT_FILENAME (t);
+ break;
+
+ case RETURN_STMT:
+ if (find_reachable_label (RETURN_STMT_EXPR (t)) != NULL_TREE)
+ return t;
+ break;
+
+ case EXPR_STMT:
+ if (find_reachable_label (EXPR_STMT_EXPR (t)) != NULL_TREE)
+ return t;
+ break;
+
+ case IF_STMT:
+ if (expand_unreachable_if_stmt (t))
+ return TREE_CHAIN (t);
+ break;
+
+ case WHILE_STMT:
+ /* If the start of a while statement is unreachable, there is
+ no need to rotate the loop, instead the WHILE_STMT can be
+ expanded like a DO_STMT. */
+ genrtl_do_stmt_1 (WHILE_COND (t), WHILE_BODY (t));
+ return TREE_CHAIN (t);
+
+ case COMPOUND_STMT:
+ {
+ tree n;
+ n = expand_unreachable_stmt (COMPOUND_BODY (t), warn);
+ if (n != NULL_TREE)
+ {
+ expand_stmt (n);
+ return TREE_CHAIN (t);
+ }
+ warn = false;
+ break;
+ }
+
+ case SCOPE_STMT:
+ saved = stmts_are_full_exprs_p ();
+ prep_stmt (t);
+ genrtl_scope_stmt (t);
+ current_stmt_tree ()->stmts_are_full_exprs_p = saved;
+ break;
+
+ default:
+ return t;
+ }
t = TREE_CHAIN (t);
}
+ return NULL_TREE;
}
+
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