/* Forward declarations */
static int global_reg_mentioned_p_1 (rtx *, void *);
static void set_of_1 (rtx, rtx, void *);
-static void insn_dependent_p_1 (rtx, rtx, void *);
static int rtx_referenced_p_1 (rtx *, void *);
static int computed_jump_p_1 (rtx);
static void parms_set (rtx, rtx, void *);
-static bool hoist_test_store (rtx, rtx, regset);
-static void hoist_update_store (rtx, rtx *, rtx, rtx);
static unsigned HOST_WIDE_INT cached_nonzero_bits (rtx, enum machine_mode,
rtx, enum machine_mode,
return 1;
}
-/* Return 1 if in between BEG and END, exclusive of BEG and END, there is
- no JUMP_INSN insn. */
-
-int
-no_jumps_between_p (rtx beg, rtx end)
-{
- rtx p;
- for (p = NEXT_INSN (beg); p != end; p = NEXT_INSN (p))
- if (JUMP_P (p))
- return 0;
- return 1;
-}
-
/* Nonzero if register REG is used in an insn between
FROM_INSN and TO_INSN (exclusive of those two). */
return 0;
}
}
-
-/* Nonzero if register REG is referenced in an insn between
- FROM_INSN and TO_INSN (exclusive of those two). Sets of REG do
- not count. */
-
-int
-reg_referenced_between_p (rtx reg, rtx from_insn, rtx to_insn)
-{
- rtx insn;
-
- if (from_insn == to_insn)
- return 0;
-
- for (insn = NEXT_INSN (from_insn); insn != to_insn; insn = NEXT_INSN (insn))
- if (INSN_P (insn)
- && (reg_referenced_p (reg, PATTERN (insn))
- || (CALL_P (insn)
- && find_reg_fusage (insn, USE, reg))))
- return 1;
- return 0;
-}
\f
/* Nonzero if register REG is set or clobbered in an insn between
FROM_INSN and TO_INSN (exclusive of those two). */
return 0;
}
-
-/* Return true if anything in insn X is (anti,output,true) dependent on
- anything in insn Y. */
-
-int
-insn_dependent_p (rtx x, rtx y)
-{
- rtx tmp;
-
- gcc_assert (INSN_P (x));
- gcc_assert (INSN_P (y));
-
- tmp = PATTERN (y);
- note_stores (PATTERN (x), insn_dependent_p_1, &tmp);
- if (tmp == NULL_RTX)
- return 1;
-
- tmp = PATTERN (x);
- note_stores (PATTERN (y), insn_dependent_p_1, &tmp);
- if (tmp == NULL_RTX)
- return 1;
-
- return 0;
-}
-
-/* A helper routine for insn_dependent_p called through note_stores. */
-
-static void
-insn_dependent_p_1 (rtx x, rtx pat ATTRIBUTE_UNUSED, void *data)
-{
- rtx * pinsn = (rtx *) data;
-
- if (*pinsn && reg_mentioned_p (x, *pinsn))
- *pinsn = NULL_RTX;
-}
\f
/* Helper function for set_of. */
struct set_of_data
return false;
}
-/* Return true when store to register X can be hoisted to the place
- with LIVE registers (can be NULL). Value VAL contains destination
- whose value will be used. */
-
-static bool
-hoist_test_store (rtx x, rtx val, regset live)
-{
- if (GET_CODE (x) == SCRATCH)
- return true;
-
- if (rtx_equal_p (x, val))
- return true;
-
- /* Allow subreg of X in case it is not writing just part of multireg pseudo.
- Then we would need to update all users to care hoisting the store too.
- Caller may represent that by specifying whole subreg as val. */
-
- if (GET_CODE (x) == SUBREG && rtx_equal_p (SUBREG_REG (x), val))
- {
- if (GET_MODE_SIZE (GET_MODE (SUBREG_REG (x))) > UNITS_PER_WORD
- && GET_MODE_BITSIZE (GET_MODE (x)) <
- GET_MODE_BITSIZE (GET_MODE (SUBREG_REG (x))))
- return false;
- return true;
- }
- if (GET_CODE (x) == SUBREG)
- x = SUBREG_REG (x);
-
- /* Anything except register store is not hoistable. This includes the
- partial stores to registers. */
-
- if (!REG_P (x))
- return false;
-
- /* Pseudo registers can be always replaced by another pseudo to avoid
- the side effect, for hard register we must ensure that they are dead.
- Eventually we may want to add code to try turn pseudos to hards, but it
- is unlikely useful. */
-
- if (REGNO (x) < FIRST_PSEUDO_REGISTER)
- {
- int regno = REGNO (x);
- int n = hard_regno_nregs[regno][GET_MODE (x)];
-
- if (!live)
- return false;
- if (REGNO_REG_SET_P (live, regno))
- return false;
- while (--n > 0)
- if (REGNO_REG_SET_P (live, regno + n))
- return false;
- }
- return true;
-}
-
-
-/* Return true if INSN can be hoisted to place with LIVE hard registers
- (LIVE can be NULL when unknown). VAL is expected to be stored by the insn
- and used by the hoisting pass. */
-
-bool
-can_hoist_insn_p (rtx insn, rtx val, regset live)
-{
- rtx pat = PATTERN (insn);
- int i;
-
- /* It probably does not worth the complexity to handle multiple
- set stores. */
- if (!single_set (insn))
- return false;
- /* We can move CALL_INSN, but we need to check that all caller clobbered
- regs are dead. */
- if (CALL_P (insn))
- return false;
- /* In future we will handle hoisting of libcall sequences, but
- give up for now. */
- if (find_reg_note (insn, REG_RETVAL, NULL_RTX))
- return false;
- switch (GET_CODE (pat))
- {
- case SET:
- if (!hoist_test_store (SET_DEST (pat), val, live))
- return false;
- break;
- case USE:
- /* USES do have sick semantics, so do not move them. */
- return false;
- break;
- case CLOBBER:
- if (!hoist_test_store (XEXP (pat, 0), val, live))
- return false;
- break;
- case PARALLEL:
- for (i = 0; i < XVECLEN (pat, 0); i++)
- {
- rtx x = XVECEXP (pat, 0, i);
- switch (GET_CODE (x))
- {
- case SET:
- if (!hoist_test_store (SET_DEST (x), val, live))
- return false;
- break;
- case USE:
- /* We need to fix callers to really ensure availability
- of all values insn uses, but for now it is safe to prohibit
- hoisting of any insn having such a hidden uses. */
- return false;
- break;
- case CLOBBER:
- if (!hoist_test_store (SET_DEST (x), val, live))
- return false;
- break;
- default:
- break;
- }
- }
- break;
- default:
- gcc_unreachable ();
- }
- return true;
-}
-
-/* Update store after hoisting - replace all stores to pseudo registers
- by new ones to avoid clobbering of values except for store to VAL that will
- be updated to NEW. */
-
-static void
-hoist_update_store (rtx insn, rtx *xp, rtx val, rtx new)
-{
- rtx x = *xp;
-
- if (GET_CODE (x) == SCRATCH)
- return;
-
- if (GET_CODE (x) == SUBREG && SUBREG_REG (x) == val)
- validate_change (insn, xp,
- simplify_gen_subreg (GET_MODE (x), new, GET_MODE (new),
- SUBREG_BYTE (x)), 1);
- if (rtx_equal_p (x, val))
- {
- validate_change (insn, xp, new, 1);
- return;
- }
- if (GET_CODE (x) == SUBREG)
- {
- xp = &SUBREG_REG (x);
- x = *xp;
- }
-
- gcc_assert (REG_P (x));
-
- /* We've verified that hard registers are dead, so we may keep the side
- effect. Otherwise replace it by new pseudo. */
- if (REGNO (x) >= FIRST_PSEUDO_REGISTER)
- validate_change (insn, xp, gen_reg_rtx (GET_MODE (x)), 1);
- REG_NOTES (insn)
- = alloc_EXPR_LIST (REG_UNUSED, *xp, REG_NOTES (insn));
-}
-
-/* Create a copy of INSN after AFTER replacing store of VAL to NEW
- and each other side effect to pseudo register by new pseudo register. */
-
-rtx
-hoist_insn_after (rtx insn, rtx after, rtx val, rtx new)
-{
- rtx pat;
- int i;
- rtx note;
- int applied;
-
- insn = emit_copy_of_insn_after (insn, after);
- pat = PATTERN (insn);
-
- /* Remove REG_UNUSED notes as we will re-emit them. */
- while ((note = find_reg_note (insn, REG_UNUSED, NULL_RTX)))
- remove_note (insn, note);
-
- /* To get this working callers must ensure to move everything referenced
- by REG_EQUAL/REG_EQUIV notes too. Lets remove them, it is probably
- easier. */
- while ((note = find_reg_note (insn, REG_EQUAL, NULL_RTX)))
- remove_note (insn, note);
- while ((note = find_reg_note (insn, REG_EQUIV, NULL_RTX)))
- remove_note (insn, note);
-
- /* Remove REG_DEAD notes as they might not be valid anymore in case
- we create redundancy. */
- while ((note = find_reg_note (insn, REG_DEAD, NULL_RTX)))
- remove_note (insn, note);
- switch (GET_CODE (pat))
- {
- case SET:
- hoist_update_store (insn, &SET_DEST (pat), val, new);
- break;
- case USE:
- break;
- case CLOBBER:
- hoist_update_store (insn, &XEXP (pat, 0), val, new);
- break;
- case PARALLEL:
- for (i = 0; i < XVECLEN (pat, 0); i++)
- {
- rtx x = XVECEXP (pat, 0, i);
- switch (GET_CODE (x))
- {
- case SET:
- hoist_update_store (insn, &SET_DEST (x), val, new);
- break;
- case USE:
- break;
- case CLOBBER:
- hoist_update_store (insn, &SET_DEST (x), val, new);
- break;
- default:
- break;
- }
- }
- break;
- default:
- gcc_unreachable ();
- }
- applied = apply_change_group ();
- gcc_assert (applied);
-
- return insn;
-}
-
-rtx
-hoist_insn_to_edge (rtx insn, edge e, rtx val, rtx new)
-{
- rtx new_insn;
-
- /* We cannot insert instructions on an abnormal critical edge.
- It will be easier to find the culprit if we die now. */
- gcc_assert (!(e->flags & EDGE_ABNORMAL) || !EDGE_CRITICAL_P (e));
-
- /* Do not use emit_insn_on_edge as we want to preserve notes and similar
- stuff. We also emit CALL_INSNS and firends. */
- if (e->insns.r == NULL_RTX)
- {
- start_sequence ();
- emit_note (NOTE_INSN_DELETED);
- }
- else
- push_to_sequence (e->insns.r);
-
- new_insn = hoist_insn_after (insn, get_last_insn (), val, new);
-
- e->insns.r = get_insns ();
- end_sequence ();
- return new_insn;
-}
-
/* Return true if LABEL is a target of JUMP_INSN. This applies only
to non-complex jumps. That is, direct unconditional, conditional,
and tablejumps, but not computed jumps or returns. It also does
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