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Commit 0a1bb917 by Bernd Schmidt Committed by Bernd Schmidt
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Avoid unnecessary dependencies on COND_EXEC insns. 

From-SVN: r38496
parent 6cbadf36
Showing with 99 additions and 16 deletions
gcc/ChangeLog
2000-12-27 Bernd Schmidt <bernds@redhat.com>
* sched-deps.c (get_condition, conditions_mutex_p): New functions.
(add_dependence): Use them to avoid adding unnecessary dependencies
between conditionally executed insns.
(sched_analyze_1, sched_analyze_2, sched_analyze_insn): Don't free
dependency lists if current insn is a COND_EXEC.
2000-12-27 Geoffrey Keating <geoffk@redhat.com>
* config/rs6000/rs6000.md (define_attr "length"): Correct
......
gcc/sched-deps.c
......@@ -82,6 +82,9 @@ static void sched_analyze_1 PARAMS ((struct deps *, rtx, rtx));
static void sched_analyze_2 PARAMS ((struct deps *, rtx, rtx));
static void sched_analyze_insn PARAMS ((struct deps *, rtx, rtx, rtx));
static rtx group_leader PARAMS ((rtx));
static rtx get_condition PARAMS ((rtx));
static int conditions_mutex_p PARAMS ((rtx, rtx));
/* Return the INSN_LIST containing INSN in LIST, or NULL
if LIST does not contain INSN. */
......@@ -119,6 +122,53 @@ find_insn_mem_list (insn, x, list, list1)
return 0;
}
/* Find the condition under which INSN is executed. */
static rtx
get_condition (insn)
rtx insn;
{
rtx pat = PATTERN (insn);
rtx cond;
if (pat == 0)
return 0;
if (GET_CODE (pat) == COND_EXEC)
return COND_EXEC_TEST (pat);
if (GET_CODE (insn) != JUMP_INSN)
return 0;
if (GET_CODE (pat) != SET || SET_SRC (pat) != pc_rtx)
return 0;
if (GET_CODE (SET_DEST (pat)) != IF_THEN_ELSE)
return 0;
pat = SET_DEST (pat);
cond = XEXP (pat, 0);
if (GET_CODE (XEXP (cond, 1)) == LABEL_REF
&& XEXP (cond, 2) == pc_rtx)
return cond;
else if (GET_CODE (XEXP (cond, 2)) == LABEL_REF
&& XEXP (cond, 1) == pc_rtx)
return gen_rtx_fmt_ee (reverse_condition (GET_CODE (cond)), GET_MODE (cond),
XEXP (cond, 0), XEXP (cond, 1));
else
return 0;
}
/* Return nonzero if conditions COND1 and COND2 can never be both true. */
static int
conditions_mutex_p (cond1, cond2)
rtx cond1, cond2;
{
if (GET_RTX_CLASS (GET_CODE (cond1)) == '<'
&& GET_RTX_CLASS (GET_CODE (cond2)) == '<'
&& GET_CODE (cond1) == reverse_condition (GET_CODE (cond2))
&& XEXP (cond1, 0) == XEXP (cond2, 0)
&& XEXP (cond1, 1) == XEXP (cond2, 1))
return 1;
return 0;
}
/* Add ELEM wrapped in an INSN_LIST with reg note kind DEP_TYPE to the
LOG_LINKS of INSN, if not already there. DEP_TYPE indicates the type
of dependence that this link represents. */
......@@ -132,6 +182,7 @@ add_dependence (insn, elem, dep_type)
rtx link, next;
int present_p;
enum reg_note present_dep_type;
rtx cond1, cond2;
/* Don't depend an insn on itself. */
if (insn == elem)
......@@ -143,6 +194,16 @@ add_dependence (insn, elem, dep_type)
if (GET_CODE (elem) == NOTE)
return;
/* flow.c doesn't handle conditional lifetimes entirely correctly;
calls mess up the conditional lifetimes. */
if (GET_CODE (insn) != CALL_INSN && GET_CODE (elem) != CALL_INSN)
{
cond1 = get_condition (insn);
cond2 = get_condition (elem);
if (cond1 && cond2 && conditions_mutex_p (cond1, cond2))
return;
}
/* If elem is part of a sequence that must be scheduled together, then
make the dependence point to the last insn of the sequence.
When HAVE_cc0, it is possible for NOTEs to exist between users and
......@@ -524,7 +585,8 @@ sched_analyze_1 (deps, x, insn)
pending clobber. */
if (code == SET)
{
free_INSN_LIST_list (&deps->reg_last_uses[r]);
if (GET_CODE (PATTERN (insn)) != COND_EXEC)
free_INSN_LIST_list (&deps->reg_last_uses[r]);
for (u = deps->reg_last_clobbers[r]; u; u = XEXP (u, 1))
add_dependence (insn, XEXP (u, 0), REG_DEP_OUTPUT);
SET_REGNO_REG_SET (reg_pending_sets, r);
......@@ -550,7 +612,8 @@ sched_analyze_1 (deps, x, insn)
if (code == SET)
{
free_INSN_LIST_list (&deps->reg_last_uses[regno]);
if (GET_CODE (PATTERN (insn)) != COND_EXEC)
free_INSN_LIST_list (&deps->reg_last_uses[regno]);
for (u = deps->reg_last_clobbers[regno]; u; u = XEXP (u, 1))
add_dependence (insn, XEXP (u, 0), REG_DEP_OUTPUT);
SET_REGNO_REG_SET (reg_pending_sets, regno);
......@@ -791,7 +854,8 @@ sched_analyze_2 (deps, x, insn)
{
for (u = deps->reg_last_uses[i]; u; u = XEXP (u, 1))
add_dependence (insn, XEXP (u, 0), REG_DEP_ANTI);
free_INSN_LIST_list (&deps->reg_last_uses[i]);
if (GET_CODE (PATTERN (insn)) != COND_EXEC)
free_INSN_LIST_list (&deps->reg_last_uses[i]);
for (u = deps->reg_last_sets[i]; u; u = XEXP (u, 1))
add_dependence (insn, XEXP (u, 0), 0);
......@@ -997,7 +1061,8 @@ sched_analyze_insn (deps, x, insn, loop_notes)
rtx u;
for (u = deps->reg_last_uses[i]; u; u = XEXP (u, 1))
add_dependence (insn, XEXP (u, 0), REG_DEP_ANTI);
free_INSN_LIST_list (&deps->reg_last_uses[i]);
if (GET_CODE (PATTERN (insn)) != COND_EXEC)
free_INSN_LIST_list (&deps->reg_last_uses[i]);
for (u = deps->reg_last_sets[i]; u; u = XEXP (u, 1))
add_dependence (insn, XEXP (u, 0), 0);
......@@ -1017,17 +1082,22 @@ sched_analyze_insn (deps, x, insn, loop_notes)
subsequent sets will be output dependent on it. */
EXECUTE_IF_SET_IN_REG_SET
(reg_pending_sets, 0, i,
{
free_INSN_LIST_list (&deps->reg_last_sets[i]);
free_INSN_LIST_list (&deps->reg_last_clobbers[i]);
deps->reg_last_sets[i] = alloc_INSN_LIST (insn, NULL_RTX);
});
{
if (GET_CODE (PATTERN (insn)) != COND_EXEC)
{
free_INSN_LIST_list (&deps->reg_last_sets[i]);
free_INSN_LIST_list (&deps->reg_last_clobbers[i]);
deps->reg_last_sets[i] = 0;
}
deps->reg_last_sets[i]
= alloc_INSN_LIST (insn, deps->reg_last_sets[i]);
});
EXECUTE_IF_SET_IN_REG_SET
(reg_pending_clobbers, 0, i,
{
deps->reg_last_clobbers[i]
= alloc_INSN_LIST (insn, deps->reg_last_clobbers[i]);
});
{
deps->reg_last_clobbers[i]
= alloc_INSN_LIST (insn, deps->reg_last_clobbers[i]);
});
CLEAR_REG_SET (reg_pending_sets);
CLEAR_REG_SET (reg_pending_clobbers);
......@@ -1035,9 +1105,14 @@ sched_analyze_insn (deps, x, insn, loop_notes)
{
for (i = 0; i < maxreg; i++)
{
free_INSN_LIST_list (&deps->reg_last_sets[i]);
free_INSN_LIST_list (&deps->reg_last_clobbers[i]);
deps->reg_last_sets[i] = alloc_INSN_LIST (insn, NULL_RTX);
if (GET_CODE (PATTERN (insn)) != COND_EXEC)
{
free_INSN_LIST_list (&deps->reg_last_sets[i]);
free_INSN_LIST_list (&deps->reg_last_clobbers[i]);
deps->reg_last_sets[i] = 0;
}
deps->reg_last_sets[i]
= alloc_INSN_LIST (insn, deps->reg_last_sets[i]);
}
reg_pending_sets_all = 0;
......
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