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riscv-gcc-1
Commit 8f7ee471 by Dale Johannesen Committed by Dale Johannesen
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loop.c (struct movable): Add insert_temp, shrink savemode. 

2003-02-28  Dale Johannesen <dalej@apple.com>

      * loop.c (struct movable): Add insert_temp, shrink savemode.
      (scan_loop): Accept invariants that require copying; mark as
      insert_temp.
      (combine_movables): Don't combine insert_temp movables.
      (move_movables): Insert copies for insert_temp movables.
      Don't record the info based on regno for insert_temp's.

From-SVN: r63572
parent 67c2b45f
Showing with 119 additions and 50 deletions
gcc/ChangeLog
2003-02-28 Dale Johannesen <dalej@apple.com>
* loop.c (struct movable): Add insert_temp, shrink savemode.
(scan_loop): Accept invariants that require copying; mark as
insert_temp.
(combine_movables): Don't combine insert_temp movables.
(move_movables): Insert copies for insert_temp movables.
Don't record the info based on regno for insert_temp's.
2003-02-28 Joel Sherrill <joel@OARcorp.com>
PR 9638/other
......
gcc/loop.c
......@@ -204,6 +204,9 @@ struct movable
short savings; /* Number of insns we can move for this reg,
including other movables that force this
or match this one. */
ENUM_BITFIELD(machine_mode) savemode : 8; /* Nonzero means it is a mode for
a low part that we should avoid changing when
clearing the rest of the reg. */
unsigned int cond : 1; /* 1 if only conditionally movable */
unsigned int force : 1; /* 1 means MUST move this insn */
unsigned int global : 1; /* 1 means reg is live outside this loop */
......@@ -220,9 +223,9 @@ struct movable
unsigned int move_insn_first:1;/* Same as above, if this is necessary for the
first insn of a consecutive sets group. */
unsigned int is_equiv : 1; /* 1 means a REG_EQUIV is present on INSN. */
enum machine_mode savemode; /* Nonzero means it is a mode for a low part
that we should avoid changing when clearing
the rest of the reg. */
unsigned int insert_temp : 1; /* 1 means we copy to a new pseudo and replace
the original insn with a copy from that
pseudo, rather than deleting it. */
struct movable *match; /* First entry for same value */
struct movable *forces; /* An insn that must be moved if this is */
struct movable *next;
......@@ -765,6 +768,7 @@ scan_loop (loop, flags)
int tem1 = 0;
int tem2 = 0;
int move_insn = 0;
int insert_temp = 0;
rtx src = SET_SRC (set);
rtx dependencies = 0;
......@@ -808,34 +812,45 @@ scan_loop (loop, flags)
}
}
if (/* The register is used in basic blocks other
than the one where it is set (meaning that
something after this point in the loop might
depend on its value before the set). */
! reg_in_basic_block_p (p, SET_DEST (set))
/* And the set is not guaranteed to be executed once
the loop starts, or the value before the set is
needed before the set occurs...
??? Note we have quadratic behavior here, mitigated
by the fact that the previous test will often fail for
large loops. Rather than re-scanning the entire loop
each time for register usage, we should build tables
of the register usage and use them here instead. */
&& (maybe_never
|| loop_reg_used_before_p (loop, set, p)))
/* It is unsafe to move the set. However, it may be OK to
move the source into a new psuedo, and subsitute a
reg-to-reg copy for the original insn.
This code used to consider it OK to move a set of a variable
which was not created by the user and not used in an exit
test.
That behavior is incorrect and was removed. */
insert_temp = 1;
/* Don't try to optimize a register that was made
by loop-optimization for an inner loop.
We don't know its life-span, so we can't compute
the benefit. */
if (REGNO (SET_DEST (set)) >= max_reg_before_loop)
;
else if (/* The register is used in basic blocks other
than the one where it is set (meaning that
something after this point in the loop might
depend on its value before the set). */
! reg_in_basic_block_p (p, SET_DEST (set))
/* And the set is not guaranteed to be executed once
the loop starts, or the value before the set is
needed before the set occurs...
??? Note we have quadratic behavior here, mitigated
by the fact that the previous test will often fail for
large loops. Rather than re-scanning the entire loop
each time for register usage, we should build tables
of the register usage and use them here instead. */
&& (maybe_never
|| loop_reg_used_before_p (loop, set, p)))
/* It is unsafe to move the set.
This code used to consider it OK to move a set of a variable
which was not created by the user and not used in an exit
test.
That behavior is incorrect and was removed. */
/* Don't move the source and add a reg-to-reg copy with -Os
(this certainly increases size) or if the source is
already a reg (the motion will gain nothing). */
else if (insert_temp
&& (optimize_size || GET_CODE (SET_SRC (set)) == REG
|| (CONSTANT_P (SET_SRC (set))
&& LEGITIMATE_CONSTANT_P (SET_SRC (set)))))
;
else if ((tem = loop_invariant_p (loop, src))
&& (dependencies == 0
......@@ -926,6 +941,7 @@ scan_loop (loop, flags)
m->partial = 0;
m->move_insn = move_insn;
m->move_insn_first = 0;
m->insert_temp = insert_temp;
m->is_equiv = (find_reg_note (p, REG_EQUIV, NULL_RTX) != 0);
m->savemode = VOIDmode;
m->regno = regno;
......@@ -1010,6 +1026,7 @@ scan_loop (loop, flags)
m->forces = 0;
m->move_insn = 0;
m->move_insn_first = 0;
m->insert_temp = insert_temp;
m->partial = 1;
/* If the insn may not be executed on some cycles,
we can't clear the whole reg; clear just high part.
......@@ -1465,6 +1482,7 @@ combine_movables (movables, regs)
for (m = movables->head; m; m = m->next)
if (m->match == 0 && regs->array[m->regno].n_times_set == 1
&& m->regno >= FIRST_PSEUDO_REGISTER
&& !m->insert_temp
&& !m->partial)
{
struct movable *m1;
......@@ -1477,6 +1495,7 @@ combine_movables (movables, regs)
one match any later ones. So start this loop at m->next. */
for (m1 = m->next; m1; m1 = m1->next)
if (m != m1 && m1->match == 0
&& !m1->insert_temp
&& regs->array[m1->regno].n_times_set == 1
&& m1->regno >= FIRST_PSEUDO_REGISTER
/* A reg used outside the loop mustn't be eliminated. */
......@@ -1880,6 +1899,10 @@ move_movables (loop, movables, threshold, insn_count)
int count;
struct movable *m1;
rtx first = NULL_RTX;
rtx newreg = NULL_RTX;
if (m->insert_temp)
newreg = gen_reg_rtx (GET_MODE (m->set_dest));
/* Now move the insns that set the reg. */
......@@ -1950,10 +1973,22 @@ move_movables (loop, movables, threshold, insn_count)
insn stream. */
while (p && GET_CODE (p) == NOTE)
p = NEXT_INSN (temp) = NEXT_INSN (p);
if (m->insert_temp)
{
/* Replace the original insn with a move from
our newly created temp. */
start_sequence ();
emit_move_insn (m->set_dest, newreg);
seq = get_insns ();
end_sequence ();
emit_insn_before (seq, p);
}
}
start_sequence ();
emit_move_insn (m->set_dest, m->set_src);
emit_move_insn (m->insert_temp ? newreg : m->set_dest,
m->set_src);
seq = get_insns ();
end_sequence ();
......@@ -2123,6 +2158,16 @@ move_movables (loop, movables, threshold, insn_count)
set_unique_reg_note (i1, m->is_equiv ? REG_EQUIV
: REG_EQUAL, m->set_src);
}
else if (m->insert_temp)
{
rtx *reg_map2 = (rtx *) xcalloc (REGNO (newreg),
sizeof(rtx));
reg_map2 [m->regno] = newreg;
i1 = loop_insn_hoist (loop, copy_rtx (PATTERN (p)));
replace_regs (i1, reg_map2, REGNO (newreg), 1);
free (reg_map2);
}
else
i1 = loop_insn_hoist (loop, PATTERN (p));
......@@ -2171,40 +2216,55 @@ move_movables (loop, movables, threshold, insn_count)
insn stream. */
while (p && GET_CODE (p) == NOTE)
p = NEXT_INSN (temp) = NEXT_INSN (p);
if (m->insert_temp)
{
rtx seq;
/* Replace the original insn with a move from
our newly created temp. */
start_sequence ();
emit_move_insn (m->set_dest, newreg);
seq = get_insns ();
end_sequence ();
emit_insn_before (seq, p);
}
}
/* The more regs we move, the less we like moving them. */
threshold -= 3;
}
/* Any other movable that loads the same register
MUST be moved. */
already_moved[regno] = 1;
/* This reg has been moved out of one loop. */
regs->array[regno].moved_once = 1;
m->done = 1;
/* The reg set here is now invariant. */
if (! m->partial)
if (!m->insert_temp)
{
int i;
for (i = 0; i < LOOP_REGNO_NREGS (regno, m->set_dest); i++)
regs->array[regno+i].set_in_loop = 0;
}
/* Any other movable that loads the same register
MUST be moved. */
already_moved[regno] = 1;
m->done = 1;
/* This reg has been moved out of one loop. */
regs->array[regno].moved_once = 1;
/* Change the length-of-life info for the register
to say it lives at least the full length of this loop.
This will help guide optimizations in outer loops. */
if (REGNO_FIRST_LUID (regno) > INSN_LUID (loop_start))
/* This is the old insn before all the moved insns.
We can't use the moved insn because it is out of range
in uid_luid. Only the old insns have luids. */
REGNO_FIRST_UID (regno) = INSN_UID (loop_start);
if (REGNO_LAST_LUID (regno) < INSN_LUID (loop_end))
REGNO_LAST_UID (regno) = INSN_UID (loop_end);
/* The reg set here is now invariant. */
if (! m->partial)
{
int i;
for (i = 0; i < LOOP_REGNO_NREGS (regno, m->set_dest); i++)
regs->array[regno+i].set_in_loop = 0;
}
/* Change the length-of-life info for the register
to say it lives at least the full length of this loop.
This will help guide optimizations in outer loops. */
if (REGNO_FIRST_LUID (regno) > INSN_LUID (loop_start))
/* This is the old insn before all the moved insns.
We can't use the moved insn because it is out of range
in uid_luid. Only the old insns have luids. */
REGNO_FIRST_UID (regno) = INSN_UID (loop_start);
if (REGNO_LAST_LUID (regno) < INSN_LUID (loop_end))
REGNO_LAST_UID (regno) = INSN_UID (loop_end);
}
/* Combine with this moved insn any other matching movables. */
......
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