diff options
Diffstat (limited to 'gcc/stmt.c')
| -rw-r--r-- | gcc/stmt.c | 43 |
1 files changed, 18 insertions, 25 deletions
@@ -2872,7 +2872,14 @@ expand_return (retval) } /* Attempt to optimize the call if it is tail recursive. */ - if (optimize_tail_recursion (retval_rhs, last_insn)) + if (optimize + && retval_rhs != NULL_TREE + && 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) + && optimize_tail_recursion (TREE_OPERAND (retval_rhs, 1), last_insn)) return; #ifdef HAVE_return @@ -3084,33 +3091,20 @@ drop_through_at_end_p () return insn && GET_CODE (insn) != BARRIER; } -/* 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. Return TRUE if the - call was optimized into a goto. - - This is only used by expand_return, but expand_call is expected to - use it soon. */ +/* Attempt to optimize a potential tail recursion call into a goto. + ARGUMENTS are the arguments to a CALL_EXPR; LAST_INSN indicates + where to place the jump to the tail recursion label. + + Return TRUE if the call was optimized into a goto. */ int -optimize_tail_recursion (call_expr, last_insn) - tree call_expr; +optimize_tail_recursion (arguments, last_insn) + tree arguments; 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))) + /* Finish checking validity, and if valid emit code to set the + argument variables for the new call. */ + if (tail_recursion_args (arguments, DECL_ARGUMENTS (current_function_decl))) { if (tail_recursion_label == 0) { @@ -3123,7 +3117,6 @@ optimize_tail_recursion (call_expr, last_insn) emit_barrier (); return 1; } - return 0; } |