/* Tail call optimization on trees.
- Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
+ Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011
Free Software Foundation, Inc.
This file is part of GCC.
#include "coretypes.h"
#include "tm.h"
#include "tree.h"
-#include "rtl.h"
#include "tm_p.h"
-#include "hard-reg-set.h"
#include "basic-block.h"
#include "function.h"
#include "tree-flow.h"
#include "tree-dump.h"
-#include "diagnostic.h"
+#include "gimple-pretty-print.h"
#include "except.h"
#include "tree-pass.h"
#include "flags.h"
#include "langhooks.h"
#include "dbgcnt.h"
+#include "target.h"
+#include "common/common-target.h"
/* The file implements the tail recursion elimination. It is also used to
analyze the tail calls in general, passing the results to the rtl level
/* If we are using sjlj exceptions, we may need to add a call to
_Unwind_SjLj_Unregister at exit of the function. Which means
that we cannot do any sibcall transformations. */
- if (USING_SJLJ_EXCEPTIONS && current_function_has_exception_handlers ())
+ if (targetm_common.except_unwind_info (&global_options) == UI_SJLJ
+ && current_function_has_exception_handlers ())
return false;
/* Any function that calls setjmp might have longjmp called from
but not in all cases. See PR15387 and PR19616. Revisit for 4.1. */
for (param = DECL_ARGUMENTS (current_function_decl);
param;
- param = TREE_CHAIN (param))
+ param = DECL_CHAIN (param))
if (TREE_ADDRESSABLE (param))
return false;
process_assignment (gimple stmt, gimple_stmt_iterator call, tree *m,
tree *a, tree *ass_var)
{
- tree op0, op1, non_ass_var;
+ tree op0, op1 = NULL_TREE, non_ass_var = NULL_TREE;
tree dest = gimple_assign_lhs (stmt);
enum tree_code code = gimple_assign_rhs_code (stmt);
enum gimple_rhs_class rhs_class = get_gimple_rhs_class (code);
return true;
}
- if (rhs_class != GIMPLE_BINARY_RHS)
- return false;
+ switch (rhs_class)
+ {
+ case GIMPLE_BINARY_RHS:
+ op1 = gimple_assign_rhs2 (stmt);
+
+ /* Fall through. */
+
+ case GIMPLE_UNARY_RHS:
+ op0 = gimple_assign_rhs1 (stmt);
+ break;
+
+ default:
+ return false;
+ }
/* Accumulator optimizations will reverse the order of operations.
We can only do that for floating-point types if we're assuming
if (FLOAT_TYPE_P (TREE_TYPE (DECL_RESULT (current_function_decl))))
return false;
- /* We only handle the code like
-
- x = call ();
- y = m * x;
- z = y + a;
- return z;
-
- TODO -- Extend it for cases where the linear transformation of the output
- is expressed in a more complicated way. */
-
- op0 = gimple_assign_rhs1 (stmt);
- op1 = gimple_assign_rhs2 (stmt);
-
- if (op0 == *ass_var
+ if (rhs_class == GIMPLE_UNARY_RHS)
+ ;
+ else if (op0 == *ass_var
&& (non_ass_var = independent_of_stmt_p (op1, stmt, call)))
;
else if (op1 == *ass_var
*ass_var = dest;
return true;
- /* TODO -- Handle other codes (NEGATE_EXPR, MINUS_EXPR,
- POINTER_PLUS_EXPR). */
+ case NEGATE_EXPR:
+ if (FLOAT_TYPE_P (TREE_TYPE (op0)))
+ *m = build_real (TREE_TYPE (op0), dconstm1);
+ else
+ *m = build_int_cst (TREE_TYPE (op0), -1);
+
+ *ass_var = dest;
+ return true;
+
+ case MINUS_EXPR:
+ if (*ass_var == op0)
+ *a = fold_build1 (NEGATE_EXPR, TREE_TYPE (non_ass_var), non_ass_var);
+ else
+ {
+ if (FLOAT_TYPE_P (TREE_TYPE (non_ass_var)))
+ *m = build_real (TREE_TYPE (non_ass_var), dconstm1);
+ else
+ *m = build_int_cst (TREE_TYPE (non_ass_var), -1);
+
+ *a = fold_build1 (NEGATE_EXPR, TREE_TYPE (non_ass_var), non_ass_var);
+ }
+
+ *ass_var = dest;
+ return true;
+
+ /* TODO -- Handle POINTER_PLUS_EXPR. */
default:
return false;
{
stmt = gsi_stmt (gsi);
- /* Ignore labels. */
- if (gimple_code (stmt) == GIMPLE_LABEL || is_gimple_debug (stmt))
+ /* Ignore labels, returns and debug stmts. */
+ if (gimple_code (stmt) == GIMPLE_LABEL
+ || gimple_code (stmt) == GIMPLE_RETURN
+ || is_gimple_debug (stmt))
continue;
/* Check for a call. */
for (param = DECL_ARGUMENTS (func), idx = 0;
param && idx < gimple_call_num_args (call);
- param = TREE_CHAIN (param), idx ++)
+ param = DECL_CHAIN (param), idx ++)
{
arg = gimple_call_arg (call, idx);
if (param != arg)
/* Make sure the tail invocation of this function does not refer
to local variables. */
- FOR_EACH_REFERENCED_VAR (var, rvi)
+ FOR_EACH_REFERENCED_VAR (cfun, var, rvi)
{
- if (!is_global_var (var)
- && ref_maybe_used_by_stmt_p (call, 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;
}
if (tmp_a)
{
+ tree type = TREE_TYPE (tmp_a);
if (a)
- a = fold_build2 (PLUS_EXPR, TREE_TYPE (tmp_a), a, tmp_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, TREE_TYPE (tmp_m), m, tmp_m);
+ m = fold_build2 (MULT_EXPR, type, fold_convert (type, m), tmp_m);
else
m = tmp_m;
if (a)
- a = fold_build2 (MULT_EXPR, TREE_TYPE (tmp_m), a, tmp_m);
+ a = fold_build2 (MULT_EXPR, type, fold_convert (type, a), tmp_m);
}
}
for (param = DECL_ARGUMENTS (current_function_decl),
idx = 0, gsi = gsi_start_phis (first);
param;
- param = TREE_CHAIN (param), idx++)
+ param = DECL_CHAIN (param), idx++)
{
if (!arg_needs_copy_p (param))
continue;
this, we cannot do much better than to rebuild the ssa form for
possibly affected virtual ssa names from scratch. */
- FOR_EACH_REFERENCED_VAR (var, rvi)
+ FOR_EACH_REFERENCED_VAR (cfun, var, rvi)
{
if (!is_gimple_reg (var) && gimple_default_def (cfun, var) != NULL_TREE)
mark_sym_for_renaming (var);
/* Copy the args if needed. */
for (param = DECL_ARGUMENTS (current_function_decl);
param;
- param = TREE_CHAIN (param))
+ param = DECL_CHAIN (param))
if (arg_needs_copy_p (param))
{
tree name = gimple_default_def (cfun, param);
integer_one_node);
}
+ if (a_acc || m_acc)
+ {
+ /* When the tail call elimination using accumulators is performed,
+ statements adding the accumulated value are inserted at all exits.
+ This turns all other tail calls to non-tail ones. */
+ opt_tailcalls = false;
+ }
+
for (; tailcalls; tailcalls = next)
{
next = tailcalls->next;
0, /* properties_provided */
0, /* properties_destroyed */
0, /* todo_flags_start */
- TODO_dump_func | TODO_verify_ssa /* todo_flags_finish */
+ TODO_verify_ssa /* todo_flags_finish */
}
};
0, /* properties_provided */
0, /* properties_destroyed */
0, /* todo_flags_start */
- TODO_dump_func | TODO_verify_ssa /* todo_flags_finish */
+ TODO_verify_ssa /* todo_flags_finish */
}
};
OSDN Git Service
