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cfglayout.c (fixup_reorder_chain): Remove kludge for the case of conditional jump jumping to the next instruction.

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* cfglayout.c (fixup_reorder_chain): Remove kludge for the
	case of conditional jump jumping to the next instruction.
	* cfgrtl.c (force_nonfallthru_and_redirect): Accept all
	cases of conditional jump jumping to the next instruction.


Co-Authored-By: Jan Hubicka <jh@suse.cz>

From-SVN: r109247
This commit is contained in:
Eric Botcazou 2006-01-02 22:47:50 +00:00 committed by Eric Botcazou
parent 99f1e97091
commit c8c3cb28fa
3 changed files with 13 additions and 36 deletions
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8
gcc/ChangeLog
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@ -1,3 +1,11 @@
2006-01-02 Eric Botcazou <ebotcazou@adacore.com>
Jan Hubicka <jh@suse.cz>
* cfglayout.c (fixup_reorder_chain): Remove kludge for the
case of conditional jump jumping to the next instruction.
* cfgrtl.c (force_nonfallthru_and_redirect): Accept all
cases of conditional jump jumping to the next instruction.
2006-01-02 Jan Hubicka <jh@suse.cz>
* i386.c (*_cost): Add COSTS_N_INSNS.

38
gcc/cfglayout.c
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@ -680,41 +680,13 @@ fixup_reorder_chain (void)
continue;
/* The degenerated case of conditional jump jumping to the next
instruction can happen on target having jumps with side
effects.
Create temporarily the duplicated edge representing branch.
It will get unidentified by force_nonfallthru_and_redirect
that would otherwise get confused by fallthru edge not pointing
to the next basic block. */
instruction can happen for jumps with side effects. We need
to construct a forwarder block and this will be done just
fine by force_nonfallthru below. */
if (!e_taken)
{
rtx note;
edge e_fake;
bool redirected;
;
e_fake = unchecked_make_edge (bb, e_fall->dest, 0);
redirected = redirect_jump (BB_END (bb),
block_label (bb), 0);
gcc_assert (redirected);
note = find_reg_note (BB_END (bb), REG_BR_PROB, NULL_RTX);
if (note)
{
int prob = INTVAL (XEXP (note, 0));
e_fake->probability = prob;
e_fake->count = e_fall->count * prob / REG_BR_PROB_BASE;
e_fall->probability -= e_fall->probability;
e_fall->count -= e_fake->count;
if (e_fall->probability < 0)
e_fall->probability = 0;
if (e_fall->count < 0)
e_fall->count = 0;
}
}
/* There is one special case: if *neither* block is next,
/* There is another special case: if *neither* block is next,
such as happens at the very end of a function, then we'll
need to add a new unconditional jump. Choose the taken
edge based on known or assumed probability. */

3
gcc/cfgrtl.c
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@ -1014,9 +1014,6 @@ force_nonfallthru_and_redirect (edge e, basic_block target)
by creating a basic block afterwards to redirect fallthru edge. */
if (e->src != ENTRY_BLOCK_PTR && e->dest != EXIT_BLOCK_PTR
&& any_condjump_p (BB_END (e->src))
/* When called from cfglayout, fallthru edges do not
necessarily go to the next block. */
&& e->src->next_bb == e->dest
&& JUMP_LABEL (BB_END (e->src)) == BB_HEAD (e->dest))
{
rtx note;