OpenE2K
/
gcc
2
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

(init_reg_last_arrays): New function. 

(combine_instructions): Use it.
(force_to_mode): Narrow mask to fit mode (except VOIDmode).
(record_value_for_reg): When zeroing reg_last_set_value, also
zero reg_last_set_{mode,nonzero_bits,sign_bit_copies}.
(record_dead_and_set_regs): Likewise.

From-SVN: r5430
This commit is contained in:
Richard Stallman 1993-09-23 06:11:30 +00:00
parent 9f5cad0582
commit ef026f9101
1 changed files with 61 additions and 37 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

98
gcc/combine.c
View File

@ -368,6 +368,7 @@ static struct undobuf undobuf;
static int n_occurrences;
static void init_reg_last_arrays PROTO(());
static void setup_incoming_promotions PROTO(());
static void set_nonzero_bits_and_sign_copies PROTO((rtx, rtx));
static int can_combine_p PROTO((rtx, rtx, rtx, rtx, rtx *, rtx *));
@ -438,6 +439,13 @@ combine_instructions (f, nregs)
combine_max_regno = nregs;
reg_nonzero_bits
= (unsigned HOST_WIDE_INT *) alloca (nregs * sizeof (HOST_WIDE_INT));
reg_sign_bit_copies = (char *) alloca (nregs * sizeof (char));
bzero (reg_nonzero_bits, nregs * sizeof (HOST_WIDE_INT));
bzero (reg_sign_bit_copies, nregs * sizeof (char));
reg_last_death = (rtx *) alloca (nregs * sizeof (rtx));
reg_last_set = (rtx *) alloca (nregs * sizeof (rtx));
reg_last_set_value = (rtx *) alloca (nregs * sizeof (rtx));
@ -451,21 +459,7 @@ combine_instructions (f, nregs)
reg_last_set_sign_bit_copies
= (char *) alloca (nregs * sizeof (char));
reg_nonzero_bits
= (unsigned HOST_WIDE_INT *) alloca (nregs * sizeof (HOST_WIDE_INT));
reg_sign_bit_copies = (char *) alloca (nregs * sizeof (char));
bzero (reg_last_death, nregs * sizeof (rtx));
bzero (reg_last_set, nregs * sizeof (rtx));
bzero (reg_last_set_value, nregs * sizeof (rtx));
bzero (reg_last_set_table_tick, nregs * sizeof (int));
bzero (reg_last_set_label, nregs * sizeof (int));
bzero (reg_last_set_invalid, nregs * sizeof (char));
bzero (reg_last_set_mode, nregs * sizeof (enum machine_mode));
bzero (reg_last_set_nonzero_bits, nregs * sizeof (HOST_WIDE_INT));
bzero (reg_last_set_sign_bit_copies, nregs * sizeof (char));
bzero (reg_nonzero_bits, nregs * sizeof (HOST_WIDE_INT));
bzero (reg_sign_bit_copies, nregs * sizeof (char));
init_reg_last_arrays ();
init_recog_no_volatile ();
@ -523,13 +517,7 @@ combine_instructions (f, nregs)
label_tick = 1;
last_call_cuid = 0;
mem_last_set = 0;
bzero (reg_last_death, nregs * sizeof (rtx));
bzero (reg_last_set, nregs * sizeof (rtx));
bzero (reg_last_set_value, nregs * sizeof (rtx));
bzero (reg_last_set_table_tick, nregs * sizeof (int));
bzero (reg_last_set_label, nregs * sizeof (int));
bzero (reg_last_set_invalid, nregs * sizeof (char));
init_reg_last_arrays ();
setup_incoming_promotions ();
for (insn = f; insn; insn = next ? next : NEXT_INSN (insn))
@ -640,6 +628,24 @@ combine_instructions (f, nregs)
nonzero_sign_valid = 0;
}
/* Wipe the reg_last_xxx arrays in preparation for another pass. */
static void
init_reg_last_arrays ()
{
int nregs = combine_max_regno;
bzero (reg_last_death, nregs * sizeof (rtx));
bzero (reg_last_set, nregs * sizeof (rtx));
bzero (reg_last_set_value, nregs * sizeof (rtx));
bzero (reg_last_set_table_tick, nregs * sizeof (int));
bzero (reg_last_set_label, nregs * sizeof (int));
bzero (reg_last_set_invalid, nregs * sizeof (char));
bzero (reg_last_set_mode, nregs * sizeof (enum machine_mode));
bzero (reg_last_set_nonzero_bits, nregs * sizeof (HOST_WIDE_INT));
bzero (reg_last_set_sign_bit_copies, nregs * sizeof (char));
}
/* Set up any promoted values for incoming argument registers. */
@ -5554,25 +5560,34 @@ force_to_mode (x, mode, mask, reg)
rtx reg;
{
enum rtx_code code = GET_CODE (x);
unsigned HOST_WIDE_INT nonzero = nonzero_bits (x, mode);
enum machine_mode op_mode;
unsigned HOST_WIDE_INT fuller_mask, nonzero;
rtx op0, op1, temp;
/* We want to perform the operation is its present mode unless we know
that the operation is valid in MODE, in which case we do the operation
in MODE. */
enum machine_mode op_mode
= ((code_to_optab[(int) code] != 0
&& (code_to_optab[(int) code]->handlers[(int) mode].insn_code
!= CODE_FOR_nothing))
? mode : GET_MODE (x));
op_mode = ((code_to_optab[(int) code] != 0
&& (code_to_optab[(int) code]->handlers[(int) mode].insn_code
!= CODE_FOR_nothing))
? mode : GET_MODE (x));
/* Truncate MASK to fit OP_MODE. */
if (op_mode)
mask &= GET_MODE_MASK (op_mode);
/* When we have an arithmetic operation, or a shift whose count we
do not know, we need to assume that all bit the up to the highest-order
bit in MASK will be needed. This is how we form such a mask. */
unsigned HOST_WIDE_INT fuller_mask
= (GET_MODE_BITSIZE (op_mode) >= HOST_BITS_PER_WIDE_INT
? GET_MODE_MASK (op_mode)
: ((HOST_WIDE_INT) 1 << (floor_log2 (mask) + 1)) - 1);
if (op_mode)
fuller_mask = (GET_MODE_BITSIZE (op_mode) >= HOST_BITS_PER_WIDE_INT
? GET_MODE_MASK (op_mode)
: ((HOST_WIDE_INT) 1 << (floor_log2 (mask) + 1)) - 1);
else
fuller_mask = ~ (HOST_WIDE_INT) 0;
/* Determine what bits of X are guaranteed to be (non)zero. */
nonzero = nonzero_bits (x, mode);
/* If none of the bits in X are needed, return a zero. */
if ((nonzero & mask) == 0)
@ -9188,13 +9203,17 @@ record_value_for_reg (reg, insn, value)
}
/* For each register modified, show we don't know its value, that
its value has been updated, and that we don't know the location of
the death of the register. */
we don't know about its bitwise content, that its value has been
updated, and that we don't know the location of the death of the
register. */
for (i = regno; i < endregno; i ++)
{
if (insn)
reg_last_set[i] = insn;
reg_last_set_value[i] = 0;
reg_last_set_mode[i] = 0;
reg_last_set_nonzero_bits[i] = 0;
reg_last_set_sign_bit_copies[i] = 0;
reg_last_death[i] = 0;
}
@ -9281,9 +9300,11 @@ record_dead_and_set_regs_1 (dest, setter)
for the things done by INSN. This is the last thing done in processing
INSN in the combiner loop.
We update reg_last_set, reg_last_set_value, reg_last_death, and also the
similar information mem_last_set (which insn most recently modified memory)
and last_call_cuid (which insn was the most recent subroutine call). */
We update reg_last_set, reg_last_set_value, reg_last_set_mode,
reg_last_set_nonzero_bits, reg_last_set_sign_bit_copies, reg_last_death,
and also the similar information mem_last_set (which insn most recently
modified memory) and last_call_cuid (which insn was the most recent
subroutine call). */
static void
record_dead_and_set_regs (insn)
@ -9316,6 +9337,9 @@ record_dead_and_set_regs (insn)
if (call_used_regs[i])
{
reg_last_set_value[i] = 0;
reg_last_set_mode[i] = 0;
reg_last_set_nonzero_bits[i] = 0;
reg_last_set_sign_bit_copies[i] = 0;
reg_last_death[i] = 0;
}