static rtx
find_oldest_value_reg (enum reg_class cl, rtx reg, struct value_data *vd)
{
unsigned int regno = REGNO (reg);
enum machine_mode mode = GET_MODE (reg);
unsigned int i;
/* If we are accessing REG in some mode other that what we set it in,
make sure that the replacement is valid. In particular, consider
(set (reg:DI r11) (...))
(set (reg:SI r9) (reg:SI r11))
(set (reg:SI r10) (...))
(set (...) (reg:DI r9))
Replacing r9 with r11 is invalid. */
if (mode != vd->e[regno].mode)
{
if (hard_regno_nregs[regno][mode]
> hard_regno_nregs[regno][vd->e[regno].mode])
return NULL_RTX;
}
for (i = vd->e[regno].oldest_regno; i != regno; i = vd->e[i].next_regno)
{
enum machine_mode oldmode = vd->e[i].mode;
rtx new_rtx;
if (!in_hard_reg_set_p (reg_class_contents[cl], mode, i))
continue;
new_rtx = maybe_mode_change (oldmode, vd->e[regno].mode, mode, i, regno);
if (new_rtx)
{
ORIGINAL_REGNO (new_rtx) = ORIGINAL_REGNO (reg);
REG_ATTRS (new_rtx) = REG_ATTRS (reg);
REG_POINTER (new_rtx) = REG_POINTER (reg);
return new_rtx;
}
}
return NULL_RTX;
}
static rtx
entry_register (struct web_entry *entry, struct ref *ref, char *used)
{
struct web_entry *root;
rtx reg, newreg;
/* Find the corresponding web and see if it has been visited. */
root = unionfind_root (entry);
if (root->reg)
return root->reg;
/* We are seeing this web for the first time, do the assignment. */
reg = DF_REF_REAL_REG (ref);
/* In case the original register is already assigned, generate new one. */
if (!used[REGNO (reg)])
newreg = reg, used[REGNO (reg)] = 1;
else if (REG_USERVAR_P (reg) && 0/*&& !flag_messy_debugging*/)
{
newreg = reg;
if (dump_file)
fprintf (dump_file,
"New web forced to keep reg=%i (user variable)\n",
REGNO (reg));
}
else
{
newreg = gen_reg_rtx (GET_MODE (reg));
REG_USERVAR_P (newreg) = REG_USERVAR_P (reg);
REG_POINTER (newreg) = REG_POINTER (reg);
REG_LOOP_TEST_P (newreg) = REG_LOOP_TEST_P (reg);
REG_ATTRS (newreg) = REG_ATTRS (reg);
if (dump_file)
fprintf (dump_file, "Web oldreg=%i newreg=%i\n", REGNO (reg),
REGNO (newreg));
}
root->reg = newreg;
return newreg;
}
static bool
copyprop_hardreg_forward_1 (basic_block bb, struct value_data *vd)
{
bool anything_changed = false;
rtx insn;
for (insn = BB_HEAD (bb); ; insn = NEXT_INSN (insn))
{
int n_ops, i, alt, predicated;
bool is_asm, any_replacements;
rtx set;
bool replaced[MAX_RECOG_OPERANDS];
bool changed = false;
struct kill_set_value_data ksvd;
if (!NONDEBUG_INSN_P (insn))
{
if (DEBUG_INSN_P (insn))
{
rtx loc = INSN_VAR_LOCATION_LOC (insn);
if (!VAR_LOC_UNKNOWN_P (loc))
replace_oldest_value_addr (&INSN_VAR_LOCATION_LOC (insn),
ALL_REGS, GET_MODE (loc),
ADDR_SPACE_GENERIC, insn, vd);
}
if (insn == BB_END (bb))
break;
else
continue;
}
set = single_set (insn);
extract_insn (insn);
if (! constrain_operands (1))
fatal_insn_not_found (insn);
preprocess_constraints ();
alt = which_alternative;
n_ops = recog_data.n_operands;
is_asm = asm_noperands (PATTERN (insn)) >= 0;
/* Simplify the code below by rewriting things to reflect
matching constraints. Also promote OP_OUT to OP_INOUT
in predicated instructions. */
predicated = GET_CODE (PATTERN (insn)) == COND_EXEC;
for (i = 0; i < n_ops; ++i)
{
int matches = recog_op_alt[i][alt].matches;
if (matches >= 0)
recog_op_alt[i][alt].cl = recog_op_alt[matches][alt].cl;
if (matches >= 0 || recog_op_alt[i][alt].matched >= 0
|| (predicated && recog_data.operand_type[i] == OP_OUT))
recog_data.operand_type[i] = OP_INOUT;
}
/* Apply changes to earlier DEBUG_INSNs if possible. */
if (vd->n_debug_insn_changes)
note_uses (&PATTERN (insn), cprop_find_used_regs, vd);
/* For each earlyclobber operand, zap the value data. */
for (i = 0; i < n_ops; i++)
if (recog_op_alt[i][alt].earlyclobber)
kill_value (recog_data.operand[i], vd);
/* Within asms, a clobber cannot overlap inputs or outputs.
I wouldn't think this were true for regular insns, but
scan_rtx treats them like that... */
note_stores (PATTERN (insn), kill_clobbered_value, vd);
/* Kill all auto-incremented values. */
/* ??? REG_INC is useless, since stack pushes aren't done that way. */
for_each_rtx (&PATTERN (insn), kill_autoinc_value, vd);
/* Kill all early-clobbered operands. */
for (i = 0; i < n_ops; i++)
if (recog_op_alt[i][alt].earlyclobber)
kill_value (recog_data.operand[i], vd);
/* Special-case plain move instructions, since we may well
be able to do the move from a different register class. */
if (set && REG_P (SET_SRC (set)))
{
rtx src = SET_SRC (set);
unsigned int regno = REGNO (src);
enum machine_mode mode = GET_MODE (src);
unsigned int i;
rtx new_rtx;
/* If we are accessing SRC in some mode other that what we
set it in, make sure that the replacement is valid. */
if (mode != vd->e[regno].mode)
{
if (hard_regno_nregs[regno][mode]
> hard_regno_nregs[regno][vd->e[regno].mode])
goto no_move_special_case;
/* And likewise, if we are narrowing on big endian the transformation
is also invalid. */
if (hard_regno_nregs[regno][mode]
< hard_regno_nregs[regno][vd->e[regno].mode]
&& (GET_MODE_SIZE (vd->e[regno].mode) > UNITS_PER_WORD
? WORDS_BIG_ENDIAN : BYTES_BIG_ENDIAN))
goto no_move_special_case;
}
/* If the destination is also a register, try to find a source
register in the same class. */
if (REG_P (SET_DEST (set)))
{
new_rtx = find_oldest_value_reg (REGNO_REG_CLASS (regno), src, vd);
if (new_rtx && validate_change (insn, &SET_SRC (set), new_rtx, 0))
{
if (dump_file)
fprintf (dump_file,
"insn %u: replaced reg %u with %u\n",
INSN_UID (insn), regno, REGNO (new_rtx));
changed = true;
goto did_replacement;
}
/* We need to re-extract as validate_change clobbers
recog_data. */
extract_insn (insn);
if (! constrain_operands (1))
fatal_insn_not_found (insn);
preprocess_constraints ();
}
/* Otherwise, try all valid registers and see if its valid. */
for (i = vd->e[regno].oldest_regno; i != regno;
i = vd->e[i].next_regno)
{
new_rtx = maybe_mode_change (vd->e[i].mode, vd->e[regno].mode,
mode, i, regno);
if (new_rtx != NULL_RTX)
{
if (validate_change (insn, &SET_SRC (set), new_rtx, 0))
{
ORIGINAL_REGNO (new_rtx) = ORIGINAL_REGNO (src);
REG_ATTRS (new_rtx) = REG_ATTRS (src);
REG_POINTER (new_rtx) = REG_POINTER (src);
if (dump_file)
fprintf (dump_file,
"insn %u: replaced reg %u with %u\n",
INSN_UID (insn), regno, REGNO (new_rtx));
changed = true;
goto did_replacement;
}
/* We need to re-extract as validate_change clobbers
recog_data. */
extract_insn (insn);
if (! constrain_operands (1))
fatal_insn_not_found (insn);
preprocess_constraints ();
}
}
}
no_move_special_case:
any_replacements = false;
/* For each input operand, replace a hard register with the
eldest live copy that's in an appropriate register class. */
for (i = 0; i < n_ops; i++)
{
replaced[i] = false;
/* Don't scan match_operand here, since we've no reg class
information to pass down. Any operands that we could
substitute in will be represented elsewhere. */
if (recog_data.constraints[i][0] == '\0')
continue;
/* Don't replace in asms intentionally referencing hard regs. */
if (is_asm && REG_P (recog_data.operand[i])
&& (REGNO (recog_data.operand[i])
== ORIGINAL_REGNO (recog_data.operand[i])))
continue;
if (recog_data.operand_type[i] == OP_IN)
{
if (recog_op_alt[i][alt].is_address)
replaced[i]
= replace_oldest_value_addr (recog_data.operand_loc[i],
recog_op_alt[i][alt].cl,
VOIDmode, ADDR_SPACE_GENERIC,
insn, vd);
else if (REG_P (recog_data.operand[i]))
replaced[i]
= replace_oldest_value_reg (recog_data.operand_loc[i],
recog_op_alt[i][alt].cl,
insn, vd);
else if (MEM_P (recog_data.operand[i]))
replaced[i] = replace_oldest_value_mem (recog_data.operand[i],
insn, vd);
}
else if (MEM_P (recog_data.operand[i]))
replaced[i] = replace_oldest_value_mem (recog_data.operand[i],
insn, vd);
/* If we performed any replacement, update match_dups. */
if (replaced[i])
{
int j;
rtx new_rtx;
new_rtx = *recog_data.operand_loc[i];
recog_data.operand[i] = new_rtx;
for (j = 0; j < recog_data.n_dups; j++)
if (recog_data.dup_num[j] == i)
validate_unshare_change (insn, recog_data.dup_loc[j], new_rtx, 1);
any_replacements = true;
}
}
if (any_replacements)
{
if (! apply_change_group ())
{
for (i = 0; i < n_ops; i++)
if (replaced[i])
{
rtx old = *recog_data.operand_loc[i];
recog_data.operand[i] = old;
}
if (dump_file)
fprintf (dump_file,
"insn %u: reg replacements not verified\n",
INSN_UID (insn));
}
else
changed = true;
}
did_replacement:
if (changed)
{
anything_changed = true;
/* If something changed, perhaps further changes to earlier
DEBUG_INSNs can be applied. */
if (vd->n_debug_insn_changes)
note_uses (&PATTERN (insn), cprop_find_used_regs, vd);
}
ksvd.vd = vd;
ksvd.ignore_set_reg = NULL_RTX;
/* Clobber call-clobbered registers. */
if (CALL_P (insn))
{
unsigned int set_regno = INVALID_REGNUM;
unsigned int set_nregs = 0;
unsigned int regno;
rtx exp;
hard_reg_set_iterator hrsi;
for (exp = CALL_INSN_FUNCTION_USAGE (insn); exp; exp = XEXP (exp, 1))
{
rtx x = XEXP (exp, 0);
if (GET_CODE (x) == SET)
{
rtx dest = SET_DEST (x);
kill_value (dest, vd);
set_value_regno (REGNO (dest), GET_MODE (dest), vd);
copy_value (dest, SET_SRC (x), vd);
ksvd.ignore_set_reg = dest;
set_regno = REGNO (dest);
set_nregs
= hard_regno_nregs[set_regno][GET_MODE (dest)];
break;
}
}
EXECUTE_IF_SET_IN_HARD_REG_SET (regs_invalidated_by_call, 0, regno, hrsi)
if (regno < set_regno || regno >= set_regno + set_nregs)
kill_value_regno (regno, 1, vd);
/* If SET was seen in CALL_INSN_FUNCTION_USAGE, and SET_SRC
of the SET isn't in regs_invalidated_by_call hard reg set,
but instead among CLOBBERs on the CALL_INSN, we could wrongly
assume the value in it is still live. */
if (ksvd.ignore_set_reg)
note_stores (PATTERN (insn), kill_clobbered_value, vd);
}
/* Notice stores. */
note_stores (PATTERN (insn), kill_set_value, &ksvd);
/* Notice copies. */
if (set && REG_P (SET_DEST (set)) && REG_P (SET_SRC (set)))
copy_value (SET_DEST (set), SET_SRC (set), vd);
if (insn == BB_END (bb))
break;
}
return anything_changed;
}