diff options
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 15 | ||||
| -rw-r--r-- | gcc/calls.c | 2 | ||||
| -rw-r--r-- | gcc/flags.h | 4 | ||||
| -rw-r--r-- | gcc/invoke.texi | 7 | ||||
| -rw-r--r-- | gcc/stmt.c | 2 | ||||
| -rw-r--r-- | gcc/toplev.c | 9 |
6 files changed, 34 insertions, 5 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 4faf2d3991f..226c83b40a2 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,18 @@ +Wed Mar 29 11:51:13 MET DST 2000 Jan Hubicka <jh@suse.cz> + + * flags.h (flag_optimize_sibling_calls): Declare. + * calls.c (expand_call): Fail sibcall when + !flag_optimize_sibling_calls + * invoke.texi (flag_optimize_sibling_calls): Document. + * toplev.c (flag_optimize_sibling_calls): New global variable. + (f_options): Add flag_optimize_sibling_calls. + (rest_of_compilation): Conditionize + optimize_sibling_and_tail_recursive_calls by + flag_optimize_sibling_calls. + (main): Set flag_optimize_sibling_calls for -O2. + * stmt.c (expand_return): Conditionize tail recursion by + flag_optimize_sibling_calls. + 2000-03-29 Richard Henderson <rth@cygnus.com> * config/i386/att.h (LOCAL_LABEL_PREFIX): Define. diff --git a/gcc/calls.c b/gcc/calls.c index 07898c328d5..a978dd45321 100644 --- a/gcc/calls.c +++ b/gcc/calls.c @@ -2034,7 +2034,7 @@ expand_call (exp, target, ignore) the call. */ try_tail_call = 0; - if (optimize >= 2 + if (flag_optimize_sibling_calls && currently_expanding_call == 1 && stmt_loop_nest_empty () && ! any_pending_cleanups (1)) diff --git a/gcc/flags.h b/gcc/flags.h index 1d7e782a361..81f5bda4c8b 100644 --- a/gcc/flags.h +++ b/gcc/flags.h @@ -299,6 +299,10 @@ extern int flag_volatile_static; extern int flag_fast_math; +/* Nonzero allows GCC to optimize sibling and tail recursive calls. */ + +extern int flag_optimize_sibling_calls; + /* Nonzero means the front end generally wants `errno' maintained by math operations, like built-in SQRT, unless overridden by flag_fast_math. */ diff --git a/gcc/invoke.texi b/gcc/invoke.texi index 51d21a10124..eb2696131d9 100644 --- a/gcc/invoke.texi +++ b/gcc/invoke.texi @@ -164,8 +164,8 @@ in the following sections. -finline-functions -finline-limit=@var{n} -fkeep-inline-functions -fmove-all-movables -fno-default-inline -fno-defer-pop -fno-function-cse -fno-inline -fno-peephole --fomit-frame-pointer -foptimize-register-moves -fregmove --frerun-cse-after-loop -frerun-loop-opt -freduce-all-givs +-fomit-frame-pointer -foptimize-register-moves -foptimize-sibling-calls +-fregmove -frerun-cse-after-loop -frerun-loop-opt -freduce-all-givs -fschedule-insns -fschedule-insns2 -fstrength-reduce -fstrict-aliasing -fthread-jumps -funroll-all-loops -funroll-loops @@ -2461,6 +2461,9 @@ restore frame pointers; it also makes an extra register available in many functions. @strong{It also makes debugging impossible on some machines.} +@item -foptimize-sibling-calls +Optimize sibling and tail recursive calls. + @ifset INTERNALS On some machines, such as the Vax, this flag has no effect, because the standard calling sequence automatically handles the frame pointer diff --git a/gcc/stmt.c b/gcc/stmt.c index 88d665e7236..f807554de15 100644 --- a/gcc/stmt.c +++ b/gcc/stmt.c @@ -2872,7 +2872,7 @@ expand_return (retval) } /* Attempt to optimize the call if it is tail recursive. */ - if (optimize + if (flag_optimize_sibling_calls && retval_rhs != NULL_TREE && frame_offset == 0 && TREE_CODE (retval_rhs) == CALL_EXPR diff --git a/gcc/toplev.c b/gcc/toplev.c index 028aad89d80..0b06ae2be8a 100644 --- a/gcc/toplev.c +++ b/gcc/toplev.c @@ -519,6 +519,10 @@ int flag_no_peephole = 0; int flag_fast_math = 0; +/* Nonzero allows GCC to optimize sibling and tail recursive calls. */ + +int flag_optimize_sibling_calls = 0; + /* Nonzero means the front end generally wants `errno' maintained by math operations, like built-in SQRT, unless overridden by flag_fast_math. */ @@ -863,6 +867,8 @@ lang_independent_options f_options[] = "Defer popping functions args from stack until later" }, {"omit-frame-pointer", &flag_omit_frame_pointer, 1, "When possible do not generate stack frames"}, + {"optimize-sibling-calls", &flag_optimize_sibling_calls, 1, + "Optimize sibling and tail recursive calls" }, {"cse-follow-jumps", &flag_cse_follow_jumps, 1, "When running CSE, follow jumps to their targets" }, {"cse-skip-blocks", &flag_cse_skip_blocks, 1, @@ -2991,7 +2997,7 @@ rest_of_compilation (decl) /* We may have potential sibling or tail recursion sites. Select one (of possibly multiple) methods of performing the call. */ init_EXPR_INSN_LIST_cache (); - if (optimize) + if (flag_optimize_sibling_calls) optimize_sibling_and_tail_recursive_calls (); if (ggc_p) @@ -4733,6 +4739,7 @@ main (argc, argv) if (optimize >= 2) { + flag_optimize_sibling_calls = 1; flag_cse_follow_jumps = 1; flag_cse_skip_blocks = 1; flag_gcse = 1; |
