-Thu Jan 7 19:52:53 1999 Gerald Pfeifer <pfeifer@dbai.tuwien.ac.at>
-
- * system.h (abort): Supply more detailed information on how to
- report an Internal Compiler Error.
-
Fri Jan 8 10:51:13 1999 Andreas Schwab <schwab@issan.cs.uni-dortmund.de>
* config/m68k/m68k.h: Declare output_function_epilogue.
Fri Jan 8 01:43:53 1999 Jeffrey A Law (law@cygnus.com)
+ * stmt.c (optimize_tail_recursion): New function, extracted from ...
+ (expand_return): Use optimize_tail_recursion.
+ * tree.h (optimize_tail_recursion): Declare.
+
* toplev.c (compile_file): Move call to output_func_start_profiler
to after the loop to emit deferred functions.
+Thu Jan 7 19:52:53 1999 Gerald Pfeifer <pfeifer@dbai.tuwien.ac.at>
+
+ * system.h (abort): Supply more detailed information on how to
+ report an Internal Compiler Error.
+
Thu Jan 7 11:26:17 1999 Mark Mitchell <mark@markmitchell.com>
* calls.c (store_unaligned_arguments_into_pseudos): Use xmalloc to
/* Expands front end tree to back end RTL for GNU C-Compiler
- Copyright (C) 1987, 88, 89, 92-97, 1998 Free Software Foundation, Inc.
+ Copyright (C) 1987, 88, 89, 92-98, 1999 Free Software Foundation, Inc.
This file is part of GNU CC.
return;
}
- /* For tail-recursive call to current function,
- just jump back to the beginning.
- It's unsafe if any auto variable in this function
- has its address taken; for simplicity,
- require stack frame to be empty. */
- if (optimize && retval_rhs != 0
- && frame_offset == 0
- && TREE_CODE (retval_rhs) == CALL_EXPR
- && TREE_CODE (TREE_OPERAND (retval_rhs, 0)) == ADDR_EXPR
- && TREE_OPERAND (TREE_OPERAND (retval_rhs, 0), 0) == current_function_decl
- /* Finish checking validity, and if valid emit code
- to set the argument variables for the new call. */
- && tail_recursion_args (TREE_OPERAND (retval_rhs, 1),
- DECL_ARGUMENTS (current_function_decl)))
- {
- if (tail_recursion_label == 0)
- {
- tail_recursion_label = gen_label_rtx ();
- emit_label_after (tail_recursion_label,
- tail_recursion_reentry);
- }
- emit_queue ();
- expand_goto_internal (NULL_TREE, tail_recursion_label, last_insn);
- emit_barrier ();
- return;
- }
+ /* Attempt to optimize the call if it is tail recursive. */
+ optimize_tail_recursion (retval_rhs, last_insn);
+
#ifdef HAVE_return
/* This optimization is safe if there are local cleanups
because expand_null_return takes care of them.
return insn && GET_CODE (insn) != BARRIER;
}
\f
+/* Test CALL_EXPR to determine if it is a potential tail recursion call
+ and emit code to optimize the tail recursion. LAST_INSN indicates where
+ to place the jump to the tail recursion label.
+
+ This is only used by expand_return, but expand_call is expected to
+ use it soon. */
+
+void
+optimize_tail_recursion (call_expr, last_insn)
+ tree call_expr;
+ rtx last_insn;
+{
+ /* For tail-recursive call to current function,
+ just jump back to the beginning.
+ It's unsafe if any auto variable in this function
+ has its address taken; for simplicity,
+ require stack frame to be empty. */
+ if (optimize && call_expr != 0
+ && frame_offset == 0
+ && TREE_CODE (call_expr) == CALL_EXPR
+ && TREE_CODE (TREE_OPERAND (call_expr, 0)) == ADDR_EXPR
+ && TREE_OPERAND (TREE_OPERAND (call_expr, 0), 0) == current_function_decl
+ /* Finish checking validity, and if valid emit code
+ to set the argument variables for the new call. */
+ && tail_recursion_args (TREE_OPERAND (call_expr, 1),
+ DECL_ARGUMENTS (current_function_decl)))
+ {
+ if (tail_recursion_label == 0)
+ {
+ tail_recursion_label = gen_label_rtx ();
+ emit_label_after (tail_recursion_label,
+ tail_recursion_reentry);
+ }
+ emit_queue ();
+ expand_goto_internal (NULL_TREE, tail_recursion_label, last_insn);
+ emit_barrier ();
+ }
+}
+
/* Emit code to alter this function's formal parms for a tail-recursive call.
ACTUALS is a list of actual parameter expressions (chain of TREE_LISTs).
FORMALS is the chain of decls of formals.
/* Front-end tree definitions for GNU compiler.
- Copyright (C) 1989, 93, 94, 95, 96, 97, 1998 Free Software Foundation, Inc.
+ Copyright (C) 1989, 93-98, 1999 Free Software Foundation, Inc.
This file is part of GNU CC.
extern void expand_null_return PROTO((void));
extern void expand_return PROTO((tree));
+extern void optimize_tail_recursion PROTO((tree, struct rtx_def *));
extern void expand_start_bindings PROTO((int));
extern void expand_end_bindings PROTO((tree, int, int));
extern void start_cleanup_deferral PROTO((void));