mirror/gcc
2
0
Fork 0
mirror of git://gcc.gnu.org/git/gcc.git synced 2025-04-15 09:00:29 +08:00
Code Issues Packages Projects Releases Wiki Activity

cfgcleanup.c (mentions_nonequal_regs): New function.

Browse Source 
* cfgcleanup.c (mentions_nonequal_regs): New function.
	(thread_jump): Use it.
	* toplev.c (rest_of_compilation): Run jump threading after
	liveness.

From-SVN: r50361
This commit is contained in:
Jan Hubicka 2002-03-06 18:16:22 +01:00 committed by Jan Hubicka
parent 2041cde455
commit fe477d8b5b
3 changed files with 41 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
gcc/ChangeLog
View File

@ -1,3 +1,10 @@
Wed Mar 6 18:14:43 CET 2002 Jan Hubicka <jh@suse.cz>
* cfgcleanup.c (mentions_nonequal_regs): New function.
(thread_jump): Use it.
* toplev.c (rest_of_compilation): Run jump threading after
liveness.
2002-03-06 Jakub Jelinek <jakub@redhat.com>
* ssa-ccp.c (ssa_ccp_substitute_constants): Backout 2002-03-05

32
gcc/cfgcleanup.c
View File

@ -89,6 +89,7 @@ static edge thread_jump PARAMS ((int, edge, basic_block));
static bool mark_effect PARAMS ((rtx, bitmap));
static void notice_new_block PARAMS ((basic_block));
static void update_forwarder_flag PARAMS ((basic_block));
static int mentions_nonequal_regs PARAMS ((rtx *, void *));
/* Set flags for newly created block. */
@ -235,6 +236,32 @@ mark_effect (exp, nonequal)
return false;
}
}
/* Return nonzero if X is an register set in regset DATA.
Called via for_each_rtx. */
static int
mentions_nonequal_regs (x, data)
rtx *x;
void *data;
{
regset nonequal = (regset) data;
if (REG_P (*x))
{
int regno;
regno = REGNO (*x);
if (REGNO_REG_SET_P (nonequal, regno))
return 1;
if (regno < FIRST_PSEUDO_REGISTER)
{
int n = HARD_REGNO_NREGS (regno, GET_MODE (*x));
while (--n > 0)
if (REGNO_REG_SET_P (nonequal, regno + n))
return 1;
}
}
return 0;
}
/* Attempt to prove that the basic block B will have no side effects and
allways continues in the same edge if reached via E. Return the edge
if exist, NULL otherwise. */
@ -338,6 +365,11 @@ thread_jump (mode, e, b)
if (failed)
goto failed_exit;
/* cond2 must not mention any register that is not equal to the
former block. */
if (for_each_rtx (&cond2, mentions_nonequal_regs, nonequal))
goto failed_exit;
/* In case liveness information is available, we need to prove equivalence
only of the live values. */
if (mode & CLEANUP_UPDATE_LIFE)

3
gcc/toplev.c
View File

@ -3019,7 +3019,8 @@ rest_of_compilation (decl)
#endif
life_analysis (insns, rtl_dump_file, PROP_FINAL);
if (optimize)
cleanup_cfg (CLEANUP_EXPENSIVE | CLEANUP_UPDATE_LIFE);
cleanup_cfg ((optimize ? CLEANUP_EXPENSIVE : 0)
| (flag_thread_jumps ? CLEANUP_THREADING : 0));
timevar_pop (TV_FLOW);
no_new_pseudos = 1;