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riscv-gcc-1
Commit e4600702 by Richard Kenner
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*** empty log message *** 

From-SVN: r1313
parent b0dda4b1
Showing with 874 additions and 431 deletions
gcc/Makefile.in
...@@ -817,7 +817,7 @@ combine.o : combine.c $(CONFIG_H) $(RTL_H) gvarargs.h flags.h \ ...@@ -817,7 +817,7 @@ combine.o : combine.c $(CONFIG_H) $(RTL_H) gvarargs.h flags.h \
insn-config.h insn-flags.h insn-codes.h insn-attr.h regs.h expr.h \ insn-config.h insn-flags.h insn-codes.h insn-attr.h regs.h expr.h \
basic-block.h recog.h real.h basic-block.h recog.h real.h
regclass.o : regclass.c $(CONFIG_H) $(RTL_H) hard-reg-set.h flags.h \ regclass.o : regclass.c $(CONFIG_H) $(RTL_H) hard-reg-set.h flags.h \
basic-block.h regs.h insn-config.h recog.h basic-block.h regs.h insn-config.h recog.h reload.h real.h
local-alloc.o : local-alloc.c $(CONFIG_H) $(RTL_H) flags.h basic-block.h \ local-alloc.o : local-alloc.c $(CONFIG_H) $(RTL_H) flags.h basic-block.h \
regs.h hard-reg-set.h insn-config.h recog.h output.h regs.h hard-reg-set.h insn-config.h recog.h output.h
global-alloc.o : global-alloc.c $(CONFIG_H) $(RTL_H) flags.h \ global-alloc.o : global-alloc.c $(CONFIG_H) $(RTL_H) flags.h \
......
gcc/cse.c
...@@ -5836,6 +5836,37 @@ cse_insn (insn, in_libcall_block) ...@@ -5836,6 +5836,37 @@ cse_insn (insn, in_libcall_block)
} }
} }
/* See if we have a CONST_INT that is already in a register in a
wider mode. */
if (src_const && src_related == 0 && GET_CODE (src_const) == CONST_INT
&& GET_MODE_CLASS (mode) == MODE_INT
&& GET_MODE_BITSIZE (mode) < BITS_PER_WORD)
{
enum machine_mode wider_mode;
for (wider_mode = GET_MODE_WIDER_MODE (mode);
GET_MODE_BITSIZE (wider_mode) <= BITS_PER_WORD
&& src_related == 0;
wider_mode = GET_MODE_WIDER_MODE (wider_mode))
{
struct table_elt *const_elt
= lookup (src_const, HASH (src_const, wider_mode), wider_mode);
if (const_elt == 0)
continue;
for (const_elt = const_elt->first_same_value;
const_elt; const_elt = const_elt->next_same_value)
if (GET_CODE (const_elt->exp) == REG)
{
src_related = gen_lowpart_if_possible (mode,
const_elt->exp);
break;
}
}
}
/* Another possibility is that we have an AND with a constant in /* Another possibility is that we have an AND with a constant in
a mode narrower than a word. If so, it might have been generated a mode narrower than a word. If so, it might have been generated
as part of an "if" which would narrow the AND. If we already as part of an "if" which would narrow the AND. If we already
......
gcc/flow.c
...@@ -2554,7 +2554,7 @@ dump_flow_info (file) ...@@ -2554,7 +2554,7 @@ dump_flow_info (file)
for (i = FIRST_PSEUDO_REGISTER; i < max_regno; i++) for (i = FIRST_PSEUDO_REGISTER; i < max_regno; i++)
if (reg_n_refs[i]) if (reg_n_refs[i])
{ {
enum reg_class class; enum reg_class class, altclass;
fprintf (file, "\nRegister %d used %d times across %d insns", fprintf (file, "\nRegister %d used %d times across %d insns",
i, reg_n_refs[i], reg_live_length[i]); i, reg_n_refs[i], reg_live_length[i]);
if (reg_basic_block[i] >= 0) if (reg_basic_block[i] >= 0)
...@@ -2568,12 +2568,17 @@ dump_flow_info (file) ...@@ -2568,12 +2568,17 @@ dump_flow_info (file)
if (PSEUDO_REGNO_BYTES (i) != UNITS_PER_WORD) if (PSEUDO_REGNO_BYTES (i) != UNITS_PER_WORD)
fprintf (file, "; %d bytes", PSEUDO_REGNO_BYTES (i)); fprintf (file, "; %d bytes", PSEUDO_REGNO_BYTES (i));
class = reg_preferred_class (i); class = reg_preferred_class (i);
if (class != GENERAL_REGS) altclass = reg_alternate_class (i);
if (class != GENERAL_REGS || altclass != ALL_REGS)
{ {
if (reg_preferred_or_nothing (i)) if (altclass == ALL_REGS || class == ALL_REGS)
fprintf (file, "; pref %s", reg_class_names[(int) class]);
else if (altclass == NO_REGS)
fprintf (file, "; %s or none", reg_class_names[(int) class]); fprintf (file, "; %s or none", reg_class_names[(int) class]);
else else
fprintf (file, "; pref %s", reg_class_names[(int) class]); fprintf (file, "; pref %s, else %s",
reg_class_names[(int) class],
reg_class_names[(int) altclass]);
} }
if (REGNO_POINTER_FLAG (i)) if (REGNO_POINTER_FLAG (i))
fprintf (file, "; pointer"); fprintf (file, "; pointer");
......
gcc/local-alloc.c
...@@ -145,9 +145,10 @@ static enum machine_mode *qty_mode; ...@@ -145,9 +145,10 @@ static enum machine_mode *qty_mode;
static int *qty_n_calls_crossed; static int *qty_n_calls_crossed;
/* Nonzero means don't allocate qty Q if we can't get its preferred class. */ /* Register class within which we allocate qty Q if we can't get
its preferred class. */
static char *qty_preferred_or_nothing; static enum reg_class *qty_alternate_class;
/* Element Q is the SCRATCH expression for which this quantity is being /* Element Q is the SCRATCH expression for which this quantity is being
allocated or 0 if this quantity is allocating registers. */ allocated or 0 if this quantity is allocating registers. */
...@@ -258,7 +259,7 @@ alloc_qty (regno, mode, size, birth) ...@@ -258,7 +259,7 @@ alloc_qty (regno, mode, size, birth)
qty_birth[qty] = birth; qty_birth[qty] = birth;
qty_n_calls_crossed[qty] = reg_n_calls_crossed[regno]; qty_n_calls_crossed[qty] = reg_n_calls_crossed[regno];
qty_min_class[qty] = reg_preferred_class (regno); qty_min_class[qty] = reg_preferred_class (regno);
qty_preferred_or_nothing[qty] = reg_preferred_or_nothing (regno); qty_alternate_class[qty] = reg_alternate_class (regno);
qty_n_refs[qty] = reg_n_refs[regno]; qty_n_refs[qty] = reg_n_refs[regno];
} }
...@@ -344,7 +345,7 @@ alloc_qty_for_scratch (scratch, n, insn, insn_code_num, insn_number) ...@@ -344,7 +345,7 @@ alloc_qty_for_scratch (scratch, n, insn, insn_code_num, insn_number)
qty_death[qty] = 2 * insn_number + 1; qty_death[qty] = 2 * insn_number + 1;
qty_n_calls_crossed[qty] = 0; qty_n_calls_crossed[qty] = 0;
qty_min_class[qty] = class; qty_min_class[qty] = class;
qty_preferred_or_nothing[qty] = 1; qty_alternate_class[qty] = NO_REGS;
qty_n_refs[qty] = 1; qty_n_refs[qty] = 1;
} }
...@@ -389,7 +390,7 @@ local_alloc () ...@@ -389,7 +390,7 @@ local_alloc ()
qty_mode = (enum machine_mode *) alloca (max_qty * sizeof (enum machine_mode)); qty_mode = (enum machine_mode *) alloca (max_qty * sizeof (enum machine_mode));
qty_n_calls_crossed = (int *) alloca (max_qty * sizeof (int)); qty_n_calls_crossed = (int *) alloca (max_qty * sizeof (int));
qty_min_class = (enum reg_class *) alloca (max_qty * sizeof (enum reg_class)); qty_min_class = (enum reg_class *) alloca (max_qty * sizeof (enum reg_class));
qty_preferred_or_nothing = (char *) alloca (max_qty); qty_alternate_class = (enum reg_class *) alloca (max_qty * sizeof (enum reg_class));
qty_n_refs = (short *) alloca (max_qty * sizeof (short)); qty_n_refs = (short *) alloca (max_qty * sizeof (short));
reg_qty = (int *) alloca (max_regno * sizeof (int)); reg_qty = (int *) alloca (max_regno * sizeof (int));
...@@ -413,7 +414,7 @@ local_alloc () ...@@ -413,7 +414,7 @@ local_alloc ()
for (i = FIRST_PSEUDO_REGISTER; i < max_regno; i++) for (i = FIRST_PSEUDO_REGISTER; i < max_regno; i++)
{ {
if (reg_basic_block[i] >= 0 && reg_n_deaths[i] == 1 if (reg_basic_block[i] >= 0 && reg_n_deaths[i] == 1
&& (reg_preferred_or_nothing (i) && (reg_alternate_class (i) == NO_REGS
|| reg_class_size[(int) reg_preferred_class (i)] > 1)) || reg_class_size[(int) reg_preferred_class (i)] > 1))
reg_qty[i] = -2; reg_qty[i] = -2;
else else
...@@ -1336,8 +1337,8 @@ block_alloc (b) ...@@ -1336,8 +1337,8 @@ block_alloc (b)
continue; continue;
} }
if (!qty_preferred_or_nothing[q]) if (qty_alternate_class[q] != NO_REGS)
qty_phys_reg[q] = find_free_reg (ALL_REGS, qty_phys_reg[q] = find_free_reg (qty_alternate_class[q],
qty_mode[q], q, 0, 0, qty_mode[q], q, 0, 0,
qty_birth[q], qty_death[q]); qty_birth[q], qty_death[q]);
} }
...@@ -1596,8 +1597,6 @@ combine_regs (usedreg, setreg, may_save_copy, insn_number, insn, already_dead) ...@@ -1596,8 +1597,6 @@ combine_regs (usedreg, setreg, may_save_copy, insn_number, insn, already_dead)
/* Update info about quantity SQTY. */ /* Update info about quantity SQTY. */
qty_n_calls_crossed[sqty] += reg_n_calls_crossed[sreg]; qty_n_calls_crossed[sqty] += reg_n_calls_crossed[sreg];
qty_n_refs[sqty] += reg_n_refs[sreg]; qty_n_refs[sqty] += reg_n_refs[sreg];
if (! reg_preferred_or_nothing (sreg))
qty_preferred_or_nothing[sqty] = 0;
if (usize < ssize) if (usize < ssize)
{ {
register int i; register int i;
...@@ -1662,6 +1661,10 @@ update_qty_class (qty, reg) ...@@ -1662,6 +1661,10 @@ update_qty_class (qty, reg)
enum reg_class rclass = reg_preferred_class (reg); enum reg_class rclass = reg_preferred_class (reg);
if (reg_class_subset_p (rclass, qty_min_class[qty])) if (reg_class_subset_p (rclass, qty_min_class[qty]))
qty_min_class[qty] = rclass; qty_min_class[qty] = rclass;
rclass = reg_alternate_class (reg);
if (reg_class_subset_p (rclass, qty_alternate_class[qty]))
qty_alternate_class[qty] = rclass;
} }
/* Handle something which alters the value of an rtx REG. /* Handle something which alters the value of an rtx REG.
......
gcc/regclass.c
/* Compute register class preferences for pseudo-registers. /* Compute register class preferences for pseudo-registers.
Copyright (C) 1987, 1988, 1991 Free Software Foundation, Inc. Copyright (C) 1987, 1988, 1991, 1992 Free Software Foundation, Inc.
This file is part of GNU CC. This file is part of GNU CC.
...@@ -30,13 +30,15 @@ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */ ...@@ -30,13 +30,15 @@ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
#include "regs.h" #include "regs.h"
#include "insn-config.h" #include "insn-config.h"
#include "recog.h" #include "recog.h"
#include "reload.h"
#include "real.h"
#ifndef REGISTER_MOVE_COST #ifndef REGISTER_MOVE_COST
#define REGISTER_MOVE_COST(x, y) 2 #define REGISTER_MOVE_COST(x, y) 2
#endif #endif
#ifndef MEMORY_MOVE_COST #ifndef MEMORY_MOVE_COST
#define MEMORY_MOVE_COST(x) 2 #define MEMORY_MOVE_COST(x) 4
#endif #endif
/* Register tables used by many passes. */ /* Register tables used by many passes. */
...@@ -129,7 +131,6 @@ enum reg_class reg_class_superunion[N_REG_CLASSES][N_REG_CLASSES]; ...@@ -129,7 +131,6 @@ enum reg_class reg_class_superunion[N_REG_CLASSES][N_REG_CLASSES];
char *reg_names[] = REGISTER_NAMES; char *reg_names[] = REGISTER_NAMES;
/* Indexed by n, gives number of times (REG n) is set or clobbered. /* Indexed by n, gives number of times (REG n) is set or clobbered.
This information remains valid for the rest of the compilation This information remains valid for the rest of the compilation
of the current function; it is used to control register allocation. of the current function; it is used to control register allocation.
...@@ -139,6 +140,16 @@ char *reg_names[] = REGISTER_NAMES; ...@@ -139,6 +140,16 @@ char *reg_names[] = REGISTER_NAMES;
short *reg_n_sets; short *reg_n_sets;
/* Maximum cost of moving from a register in one class to a register in
another class. Based on REGISTER_MOVE_COST. */
static int move_cost[N_REG_CLASSES][N_REG_CLASSES];
/* Similar, but here we don't have to move if the first index is a subset
of the second so in that case the cost is zero. */
static int may_move_cost[N_REG_CLASSES][N_REG_CLASSES];
/* Function called only once to initialize the above data on reg usage. /* Function called only once to initialize the above data on reg usage.
Once this is done, various switches may override. */ Once this is done, various switches may override. */
...@@ -253,6 +264,38 @@ init_reg_sets () ...@@ -253,6 +264,38 @@ init_reg_sets ()
*p = (enum reg_class) i; *p = (enum reg_class) i;
} }
} }
/* Initialize the move cost table. Find every subset of each class
and take the maximum cost of moving any subset to any other. */
for (i = 0; i < N_REG_CLASSES; i++)
for (j = 0; j < N_REG_CLASSES; j++)
{
int cost = i == j ? 2 : REGISTER_MOVE_COST (i, j);
enum reg_class *p1, *p2;
for (p2 = &reg_class_subclasses[j][0]; *p2 != LIM_REG_CLASSES; p2++)
if (*p2 != i)
cost = MAX (cost, REGISTER_MOVE_COST (i, *p2));
for (p1 = &reg_class_subclasses[i][0]; *p1 != LIM_REG_CLASSES; p1++)
{
if (*p1 != j)
cost = MAX (cost, REGISTER_MOVE_COST (*p1, j));
for (p2 = &reg_class_subclasses[j][0];
*p2 != LIM_REG_CLASSES; p2++)
if (*p1 != *p2)
cost = MAX (cost, REGISTER_MOVE_COST (*p1, *p2));
}
move_cost[i][j] = cost;
if (reg_class_subset_p (i, j))
cost = 0;
may_move_cost[i][j] = cost;
}
} }
/* After switches have been processed, which perhaps alter /* After switches have been processed, which perhaps alter
...@@ -340,18 +383,25 @@ fix_register (name, fixed, call_used) ...@@ -340,18 +383,25 @@ fix_register (name, fixed, call_used)
/* Now the data and code for the `regclass' pass, which happens /* Now the data and code for the `regclass' pass, which happens
just before local-alloc. */ just before local-alloc. */
/* savings[R].savings[CL] is twice the amount saved by putting register R /* The `costs' struct records the cost of using a hard register of each class
in class CL. This data is used within `regclass' and freed and of using memory for each pseudo. We use this data to set up
when it is finished. */ register class preferences. */
struct savings struct costs
{ {
short savings[N_REG_CLASSES]; int cost[N_REG_CLASSES];
short memcost; int mem_cost;
short nrefs;
}; };
static struct savings *savings; /* Record the cost of each class for each pseudo. */
static struct costs *costs;
/* Record the same data by operand number, accumulated for each alternative
in an insn. The contribution to a pseudo is that of the minimum-cost
alternative. */
static struct costs op_costs[MAX_RECOG_OPERANDS];
/* (enum reg_class) prefclass[R] is the preferred class for pseudo number R. /* (enum reg_class) prefclass[R] is the preferred class for pseudo number R.
This is available after `regclass' is run. */ This is available after `regclass' is run. */
...@@ -385,12 +435,13 @@ reg_preferred_class (regno) ...@@ -385,12 +435,13 @@ reg_preferred_class (regno)
return (enum reg_class) prefclass[regno]; return (enum reg_class) prefclass[regno];
} }
int enum reg_class
reg_preferred_or_nothing (regno) reg_alternate_class (regno)
{ {
if (prefclass == 0) if (prefclass == 0)
return 0; return ALL_REGS;
return preferred_or_nothing[regno];
return (enum reg_class) altclass[regno];
} }
/* This prevents dump_flow_info from losing if called /* This prevents dump_flow_info from losing if called
...@@ -414,394 +465,756 @@ regclass (f, nregs) ...@@ -414,394 +465,756 @@ regclass (f, nregs)
{ {
#ifdef REGISTER_CONSTRAINTS #ifdef REGISTER_CONSTRAINTS
register rtx insn; register rtx insn;
register int i; register int i, j;
struct costs init_cost;
rtx set;
int pass;
init_recog (); init_recog ();
/* Zero out our accumulation of the cost of each class for each reg. */ init_cost.mem_cost = 10000;
for (i = 0; i < N_REG_CLASSES; i++)
init_cost.cost[i] = 10000;
savings = (struct savings *) alloca (nregs * sizeof (struct savings)); /* Normally we scan the insns once and determine the best class to use for
bzero (savings, nregs * sizeof (struct savings)); each register. However, if -fexpensive_optimizations are on, we do so
twice, the second time using the tentative best classes to guide the
selection. */
loop_depth = 1; for (pass = 0; pass <= flag_expensive_optimizations; pass++)
{
/* Zero out our accumulation of the cost of each class for each reg. */
/* Scan the instructions and record each time it would costs = (struct costs *) alloca (nregs * sizeof (struct costs));
save code to put a certain register in a certain class. */ bzero (costs, nregs * sizeof (struct costs));
for (insn = f; insn; insn = NEXT_INSN (insn)) loop_depth = 0, loop_cost = 1;
{
if (GET_CODE (insn) == NOTE /* Scan the instructions and record each time it would
&& NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_BEG) save code to put a certain register in a certain class. */
loop_depth++;
else if (GET_CODE (insn) == NOTE for (insn = f; insn; insn = NEXT_INSN (insn))
&& NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_END)
loop_depth--;
else if ((GET_CODE (insn) == INSN
&& GET_CODE (PATTERN (insn)) != USE
&& GET_CODE (PATTERN (insn)) != CLOBBER
&& GET_CODE (PATTERN (insn)) != ASM_INPUT)
|| (GET_CODE (insn) == JUMP_INSN
&& GET_CODE (PATTERN (insn)) != ADDR_VEC
&& GET_CODE (PATTERN (insn)) != ADDR_DIFF_VEC)
|| GET_CODE (insn) == CALL_INSN)
{ {
if (GET_CODE (insn) == INSN && asm_noperands (PATTERN (insn)) >= 0) char *constraints[MAX_RECOG_OPERANDS];
enum machine_mode modes[MAX_RECOG_OPERANDS];
int nalternatives;
int noperands;
/* Show that an insn inside a loop is likely to be executed three
times more than insns outside a loop. This is much more agressive
than the assumptions made elsewhere and is being tried as an
experiment. */
if (GET_CODE (insn) == NOTE
&& NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_BEG)
loop_depth++, loop_cost = 1 << (2 * MIN (loop_depth, 5));
else if (GET_CODE (insn) == NOTE
&& NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_END)
loop_depth--, loop_cost = 1 << (2 * MIN (loop_depth, 5));
else if ((GET_CODE (insn) == INSN
&& GET_CODE (PATTERN (insn)) != USE
&& GET_CODE (PATTERN (insn)) != CLOBBER
&& GET_CODE (PATTERN (insn)) != ASM_INPUT)
|| (GET_CODE (insn) == JUMP_INSN
&& GET_CODE (PATTERN (insn)) != ADDR_VEC
&& GET_CODE (PATTERN (insn)) != ADDR_DIFF_VEC)
|| GET_CODE (insn) == CALL_INSN)
{ {
int noperands = asm_noperands (PATTERN (insn)); if (GET_CODE (insn) == INSN
/* We don't use alloca because alloca would not free && (noperands = asm_noperands (PATTERN (insn))) >= 0)
any of the space until this function returns. */ {
rtx *operands = (rtx *) oballoc (noperands * sizeof (rtx)); decode_asm_operands (PATTERN (insn), recog_operand, 0,
char **constraints constraints, modes);
= (char **) oballoc (noperands * sizeof (char *)); nalternatives = n_occurrences (',', constraints[0]) + 1;
}
else
{
int insn_code_number = recog_memoized (insn);
rtx note;
decode_asm_operands (PATTERN (insn), operands, 0, constraints, 0); set = single_set (insn);
insn_extract (insn);
for (i = noperands - 1; i >= 0; i--) nalternatives = insn_n_alternatives[insn_code_number];
reg_class_record (operands[i], i, constraints); noperands = insn_n_operands[insn_code_number];
obfree (operands); /* If this insn loads a parameter from its stack slot, then
} it represents a savings, rather than a cost, if the
else parameter is stored in memory. Record this fact. */
{
int insn_code_number = recog_memoized (insn);
rtx set = single_set (insn);
insn_extract (insn); if (set != 0 && GET_CODE (SET_DEST (set)) == REG
&& GET_CODE (SET_SRC (set)) == MEM
&& (note = find_reg_note (insn, REG_EQUIV, 0)) != 0
&& GET_CODE (XEXP (note, 0)) == MEM)
{
costs[REGNO (SET_DEST (set))].mem_cost
-= (MEMORY_MOVE_COST (GET_MODE (SET_DEST (set)))
* loop_cost);
record_address_regs (XEXP (SET_SRC (set), 0),
BASE_REG_CLASS, loop_cost * 2);
continue;
}
/* Improve handling of two-address insns such as
(set X (ashift CONST Y)) where CONST must be made to
match X. Change it into two insns: (set X CONST)
(set X (ashift X Y)). If we left this for reloading, it
would probably get three insns because X and Y might go
in the same place. This prevents X and Y from receiving
the same hard reg.
We can only do this if the modes of operands 0 and 1
(which might not be the same) are tieable and we only need
do this during our first pass. */
if (pass == 0 && optimize
&& noperands >= 3
&& insn_operand_constraint[insn_code_number][1][0] == '0'
&& insn_operand_constraint[insn_code_number][1][1] == 0
&& CONSTANT_P (recog_operand[1])
&& ! rtx_equal_p (recog_operand[0], recog_operand[1])
&& ! rtx_equal_p (recog_operand[0], recog_operand[2])
&& GET_CODE (recog_operand[0]) == REG
&& MODES_TIEABLE_P (GET_MODE (recog_operand[0]),
insn_operand_mode[insn_code_number][1]))
{
rtx previnsn = prev_real_insn (insn);
rtx dest
= gen_lowpart (insn_operand_mode[insn_code_number][1],
recog_operand[0]);
rtx newinsn
= emit_insn_before (gen_move_insn (dest,
recog_operand[1]),
insn);
/* If this insn was the start of a basic block,
include the new insn in that block. */
if (previnsn == 0 || GET_CODE (previnsn) == JUMP_INSN)
{
int b;
for (b = 0; b < n_basic_blocks; b++)
if (insn == basic_block_head[b])
basic_block_head[b] = newinsn;
}
/* This makes one more setting of new insns's dest. */
reg_n_sets[REGNO (recog_operand[0])]++;
insn = PREV_INSN (newinsn);
continue;
}
for (i = insn_n_operands[insn_code_number] - 1; i >= 0; i--) /* If this is setting a pseudo from another pseudo or the
reg_class_record (recog_operand[i], i, sum of a pseudo and a constant integer and the other
insn_operand_constraint[insn_code_number]); pseudo is known to be a pointer, set the destination to
be a pointer as well.
Likewise if it is setting the destination from an address
or from a value equivalent to an address or to the sum of
an address and something else.
But don't do any of this if the pseudo corresponds to
a user variable since it should have already been set
as a pointer based on the type.
There is no point in doing this during our second
pass since not enough should have changed. */
if (pass == 0 && set != 0 && GET_CODE (SET_DEST (set)) == REG
&& REGNO (SET_DEST (set)) >= FIRST_PSEUDO_REGISTER
&& ! REG_USERVAR_P (SET_DEST (set))
&& ! REGNO_POINTER_FLAG (REGNO (SET_DEST (set)))
&& ((GET_CODE (SET_SRC (set)) == REG
&& REGNO_POINTER_FLAG (REGNO (SET_SRC (set))))
|| ((GET_CODE (SET_SRC (set)) == PLUS
|| GET_CODE (SET_SRC (set)) == LO_SUM)
&& (GET_CODE (XEXP (SET_SRC (set), 1))
== CONST_INT)
&& GET_CODE (XEXP (SET_SRC (set), 0)) == REG
&& REGNO_POINTER_FLAG (REGNO (XEXP (SET_SRC (set), 0))))
|| GET_CODE (SET_SRC (set)) == CONST
|| GET_CODE (SET_SRC (set)) == SYMBOL_REF
|| GET_CODE (SET_SRC (set)) == LABEL_REF
|| (GET_CODE (SET_SRC (set)) == HIGH
&& (GET_CODE (XEXP (SET_SRC (set), 0)) == CONST
|| (GET_CODE (XEXP (SET_SRC (set), 0))
== SYMBOL_REF)
|| (GET_CODE (XEXP (SET_SRC (set), 0))
== LABEL_REF)))
|| ((GET_CODE (SET_SRC (set)) == PLUS
|| GET_CODE (SET_SRC (set)) == LO_SUM)
&& (GET_CODE (XEXP (SET_SRC (set), 1)) == CONST
|| (GET_CODE (XEXP (SET_SRC (set), 1))
== SYMBOL_REF)
|| (GET_CODE (XEXP (SET_SRC (set), 1))
== LABEL_REF)))
|| ((note = find_reg_note (insn, REG_EQUAL, 0)) != 0
&& (GET_CODE (XEXP (note, 0)) == CONST
|| GET_CODE (XEXP (note, 0)) == SYMBOL_REF
|| GET_CODE (XEXP (note, 0)) == LABEL_REF))))
REGNO_POINTER_FLAG (REGNO (SET_DEST (set))) = 1;
for (i = 0; i < noperands; i++)
{
constraints[i]
= insn_operand_constraint[insn_code_number][i];
modes[i] = insn_operand_mode[insn_code_number][i];
}
}
/* If this insn loads a parameter from its stack slot, /* If we get here, we are set up to record the costs of all the
then it represents a savings, rather than a cost, operands for this insn. Start by initializing the costs.
if the parameter is stored in memory. Record this fact. */ Then handle any address registers. Finally record the desired
if (set != 0 && GET_CODE (SET_DEST (set)) == REG classes for any pseudos, doing it twice if some pair of
&& GET_CODE (SET_SRC (set)) == MEM) operands are commutative. */
for (i = 0; i < noperands; i++)
{ {
rtx note = find_reg_note (insn, REG_EQUIV, 0); op_costs[i] = init_cost;
if (note != 0 && GET_CODE (XEXP (note, 0)) == MEM)
savings[REGNO (SET_DEST (set))].memcost if (GET_CODE (recog_operand[i]) == SUBREG)
-= (MEMORY_MOVE_COST (GET_MODE (SET_DEST (set))) recog_operand[i] = SUBREG_REG (recog_operand[i]);
* loop_depth);
if (GET_CODE (recog_operand[i]) == MEM)
record_address_regs (XEXP (recog_operand[i], 0),
BASE_REG_CLASS, loop_cost * 2);
else if (constraints[i][0] == 'p')
record_address_regs (recog_operand[i],
BASE_REG_CLASS, loop_cost * 2);
} }
/* Check for commutative in a separate loop so everything will
have been initialized. Don't bother doing anything if the
second operand is a constant since that is the case
for which the constraints should have been written. */
/* Improve handling of two-address insns such as for (i = 0; i < noperands; i++)
(set X (ashift CONST Y)) where CONST must be made to match X. if (constraints[i][0] == '%'
Change it into two insns: (set X CONST) (set X (ashift X Y)). && ! CONSTANT_P (recog_operand[i+1]))
If we left this for reloading, it would probably get three {
insns because X and Y might go in the same place. char *xconstraints[MAX_RECOG_OPERANDS];
This prevents X and Y from receiving the same hard reg. int j;
We can only do this if the modes of operands 0 and 1 (which /* Handle commutative operands by swapping the constraints.
might not be the same) are tieable. */ We assume the modes are the same. */
if (optimize for (j = 0; j < noperands; j++)
&& insn_n_operands[insn_code_number] >= 3 xconstraints[j] = constraints[j];
&& insn_operand_constraint[insn_code_number][1][0] == '0'
&& insn_operand_constraint[insn_code_number][1][1] == 0 xconstraints[i] = constraints[i+1];
&& CONSTANT_P (recog_operand[1]) xconstraints[i+1] = constraints[i];
&& ! rtx_equal_p (recog_operand[0], recog_operand[1]) record_reg_classes (nalternatives, noperands,
&& ! rtx_equal_p (recog_operand[0], recog_operand[2]) recog_operand, modes, xconstraints,
&& GET_CODE (recog_operand[0]) == REG
&& MODES_TIEABLE_P (GET_MODE (recog_operand[0]),
insn_operand_mode[insn_code_number][1]))
{
rtx previnsn = prev_real_insn (insn);
rtx dest
= gen_lowpart (insn_operand_mode[insn_code_number][1],
recog_operand[0]);
rtx newinsn
= emit_insn_before (gen_move_insn (dest, recog_operand[1]),
insn); insn);
}
/* If this insn was the start of a basic block, record_reg_classes (nalternatives, noperands, recog_operand,
include the new insn in that block. */ modes, constraints, insn);
if (previnsn == 0 || GET_CODE (previnsn) == JUMP_INSN)
{
int b;
for (b = 0; b < n_basic_blocks; b++)
if (insn == basic_block_head[b])
basic_block_head[b] = newinsn;
}
/* This makes one more setting of new insns's destination. */ /* Now add the cost for each operand to the total costs for
reg_n_sets[REGNO (recog_operand[0])]++; its register. */
*recog_operand_loc[1] = recog_operand[0]; for (i = 0; i < noperands; i++)
for (i = insn_n_dups[insn_code_number] - 1; i >= 0; i--) if (GET_CODE (recog_operand[i]) == REG
if (recog_dup_num[i] == 1) && REGNO (recog_operand[i]) >= FIRST_PSEUDO_REGISTER)
*recog_dup_loc[i] = recog_operand[0]; {
} int regno = REGNO (recog_operand[i]);
struct costs *p = &costs[regno], *q = &op_costs[i];
p->mem_cost += q->mem_cost * loop_cost;
for (j = 0; j < N_REG_CLASSES; j++)
p->cost[j] += q->cost[j] * loop_cost;
}
} }
} }
}
/* Now for each register look at how desirable each class is /* Now for each register look at how desirable each class is
and find which class is preferred. Store that in `prefclass[REGNO]'. */ and find which class is preferred. Store that in
`prefclass[REGNO]'. Record in `altclass[REGNO]' the largest register
prefclass = (char *) oballoc (nregs); class any of whose registers is better than memory. */
preferred_or_nothing = (char *) oballoc (nregs); if (pass == 0)
{
for (i = FIRST_PSEUDO_REGISTER; i < nregs; i++) prefclass = (char *) oballoc (nregs);
{ altclass = (char *) oballoc (nregs);
register int best_savings = 0; }
enum reg_class best = ALL_REGS;
/* This is an enum reg_class, but we call it an int
to save lots of casts. */
register int class;
register struct savings *p = &savings[i];
for (class = (int) ALL_REGS - 1; class > 0; class--) for (i = FIRST_PSEUDO_REGISTER; i < nregs; i++)
{ {
if (p->savings[class] > best_savings) register int best_cost = (1 << (HOST_BITS_PER_INT - 1)) - 1;
enum reg_class best = ALL_REGS, alt = NO_REGS;
/* This is an enum reg_class, but we call it an int
to save lots of casts. */
register int class;
register struct costs *p = &costs[i];
for (class = (int) ALL_REGS - 1; class > 0; class--)
{ {
best_savings = p->savings[class]; /* Ignore classes that are too small for this operand. */
best = (enum reg_class) class; if (CLASS_MAX_NREGS (class, PSEUDO_REGNO_MODE (i))
} > reg_class_size[class])
else if (p->savings[class] == best_savings) ;
{ else if (p->cost[class] < best_cost)
best = reg_class_subunion[(int)best][class]; {
best_cost = p->cost[class];
best = (enum reg_class) class;
}
else if (p->cost[class] == best_cost)
best = reg_class_subunion[(int)best][class];
} }
}
#if 0
/* Note that best_savings is twice number of places something
is saved. */
if ((best_savings - p->savings[(int) GENERAL_REGS]) * 5 < reg_n_refs[i])
prefclass[i] = (int) GENERAL_REGS;
else
prefclass[i] = (int) best;
#else
/* We cast to (int) because (char) hits bugs in some compilers. */
prefclass[i] = (int) best;
#endif
/* reg_n_refs + p->memcost measures the cost of putting in memory. /* Record the alternate register class; i.e., a class for which
If a GENERAL_REG is no better, don't even try for one. every register in it is better than using memory. If adding a
Since savings and memcost are 2 * number of refs, class would make a smaller class (i.e., no union of just those
this effectively counts each memory operand not needing reloading classes exists), skip that class. The major unions of classes
as costing 1/2 of a reload insn. */ should be provided as a register class. Don't do this if we
if (reg_n_refs != 0) will be doing it again later. */
preferred_or_nothing[i]
= ((best_savings - p->savings[(int) GENERAL_REGS]) if (pass == 1 || ! flag_expensive_optimizations)
>= p->nrefs + p->memcost); for (class = 0; class < N_REG_CLASSES; class++)
if (p->cost[class] < p->mem_cost
&& (reg_class_size[reg_class_subunion[(int) alt][class]]
> reg_class_size[(int) alt]))
alt = reg_class_subunion[(int) alt][class];
/* If we don't add any classes, nothing to try. */
if (alt == best)
alt = (int) NO_REGS;
/* We cast to (int) because (char) hits bugs in some compilers. */
prefclass[i] = (int) best;
altclass[i] = (int) alt;
}
} }
#endif /* REGISTER_CONSTRAINTS */ #endif /* REGISTER_CONSTRAINTS */
} }
#ifdef REGISTER_CONSTRAINTS #ifdef REGISTER_CONSTRAINTS
/* Scan an operand OP for register class preferences. /* Record the cost of using memory or registers of various classes for
OPNO is the operand number, and CONSTRAINTS is the constraint the operands in INSN.
vector for the insn.
Record the preferred register classes from the constraint for OP N_ALTS is the number of alternatives.
if OP is a register. If OP is a memory reference, record suitable
preferences for registers used in the address. */
void N_OPS is the number of operands.
reg_class_record (op, opno, constraints)
rtx op; OPS is an array of the operands.
int opno;
MODES are the modes of the operands, in case any are VOIDmode.
CONSTRAINTS are the constraints to use for the operands. This array
is modified by this procedure.
This procedure works alternative by alternative. For each alternative
we assume that we will be able to allocate all pseudos to their ideal
register class and calculate the cost of using that alternative. Then
we compute for each operand that is a pseudo-register, the cost of
having the pseudo allocated to each register class and using it in that
alternative. To this cost is added the cost of the alternative.
The cost of each class for this insn is its lowest cost among all the
alternatives. */
static void
record_reg_classes (n_alts, n_ops, ops, modes, constraints, insn)
int n_alts;
int n_ops;
rtx *ops;
enum machine_mode *modes;
char **constraints; char **constraints;
rtx insn;
{ {
char *constraint = constraints[opno]; int alt;
register char *p; enum op_type {OP_READ, OP_WRITE, OP_READ_WRITE} op_types[MAX_RECOG_OPERANDS];
register enum reg_class class = NO_REGS; int i, j;
char *next = 0;
int memok = 0; /* By default, each operand is an input operand. */
int double_cost = 0;
if (op == 0) for (i = 0; i < n_ops; i++)
return; op_types[i] = OP_READ;
while (1) /* Process each alternative, each time minimizing an operand's cost with
the cost for each operand in that alternative. */
for (alt = 0; alt < n_alts; alt++)
{ {
if (GET_CODE (op) == SUBREG) struct costs this_op_costs[MAX_RECOG_OPERANDS];
op = SUBREG_REG (op); int alt_fail = 0;
else break; int alt_cost = 0;
} enum reg_class classes[MAX_RECOG_OPERANDS];
int class;
/* Memory reference: scan the address. */ for (i = 0; i < n_ops; i++)
{
char *p = constraints[i];
rtx op = ops[i];
enum machine_mode mode = modes[i];
int allows_mem = 0;
int win = 0;
char c;
if (GET_CODE (op) == MEM) /* If this operand has no constraints at all, we can conclude
record_address_regs (XEXP (op, 0), 2, 0); nothing about it since anything is valid. */
if (GET_CODE (op) != REG) if (*p == 0)
{ {
/* If the constraint says the operand is supposed to BE an address, if (GET_CODE (op) == REG && REGNO (op) >= FIRST_PSEUDO_REGISTER)
scan it as one. */ bzero ((char *) &this_op_costs[i], sizeof this_op_costs[i]);
if (constraint != 0 && constraint[0] == 'p') continue;
record_address_regs (op, 2, 0); }
return;
}
/* Operand is a register: examine the constraint for specified classes. */ /* If this alternative is only relevant when this operand
matches a previous operand, we do different things depending
on whether this operand is a pseudo-reg or not. */
for (p = constraint; *p || next; p++) if (p[0] >= '0' && p[0] <= '0' + i && (p[1] == ',' || p[1] == 0))
{ {
enum reg_class new_class = NO_REGS; j = p[0] - '0';
classes[i] = classes[j];
if (GET_CODE (op) != REG || REGNO (op) < FIRST_PSEUDO_REGISTER)
{
/* If this matches the other operand, we have no added
cost. */
if (rtx_equal_p (ops[j], op))
;
/* If we can't put the other operand into a register, this
alternative can't be used. */
else if (classes[j] == NO_REGS)
alt_fail = 1;
/* Otherwise, add to the cost of this alternative the cost
to copy this operand to the register used for the other
operand. */
else
alt_cost += copy_cost (op, mode, classes[j], 1);
}
else
{
/* The costs of this operand are the same as that of the
other operand. However, if we cannot tie them, this
alternative needs to do a copy, which is one
instruction. */
this_op_costs[i] = this_op_costs[j];
if (! find_reg_note (insn, REG_DEAD, op))
alt_cost += 2;
}
continue;
}
/* Scan all the constraint letters. See if the operand matches
any of the constraints. Collect the valid register classes
and see if this operand accepts memory. */
classes[i] = NO_REGS;
while (*p && (c = *p++) != ',')
switch (c)
{
case '=':
op_types[i] = OP_WRITE;
break;
case '+':
op_types[i] = OP_READ_WRITE;
break;
case '*':
/* Ignore the next letter for this pass. */
p++;
break;
case '%':
case '?': case '!': case '#':
case '&':
case '0': case '1': case '2': case '3': case '4':
case 'p':
break;
case 'm': case 'o': case 'V':
/* It doesn't seem worth distingishing between offsettable
and non-offsettable addresses here. */
allows_mem = 1;
if (GET_CODE (op) == MEM)
win = 1;
break;
case '<':
if (GET_CODE (op) == MEM
&& (GET_CODE (XEXP (op, 0)) == PRE_DEC
|| GET_CODE (XEXP (op, 0)) == POST_DEC))
win = 1;
break;
case '>':
if (GET_CODE (op) == MEM
&& (GET_CODE (XEXP (op, 0)) == PRE_INC
|| GET_CODE (XEXP (op, 0)) == POST_INC))
win = 1;
break;
case 'E':
/* Match any floating double constant, but only if
we can examine the bits of it reliably. */
if ((HOST_FLOAT_FORMAT != TARGET_FLOAT_FORMAT
|| HOST_BITS_PER_INT != BITS_PER_WORD)
&& GET_MODE (op) != VOIDmode && ! flag_pretend_float)
break;
if (GET_CODE (op) == CONST_DOUBLE)
win = 1;
break;
case 'F':
if (GET_CODE (op) == CONST_DOUBLE)
win = 1;
break;
case 'G':
case 'H':
if (GET_CODE (op) == CONST_DOUBLE
&& CONST_DOUBLE_OK_FOR_LETTER_P (op, c))
win = 1;
break;
case 's':
if (GET_CODE (op) == CONST_INT
|| (GET_CODE (op) == CONST_DOUBLE
&& GET_MODE (op) == VOIDmode))
break;
case 'i':
if (CONSTANT_P (op)
#ifdef LEGITIMATE_PIC_OPERAND_P
&& (! flag_pic || LEGITIMATE_PIC_OPERAND_P (op))
#endif
)
win = 1;
break;
case 'n':
if (GET_CODE (op) == CONST_INT
|| (GET_CODE (op) == CONST_DOUBLE
&& GET_MODE (op) == VOIDmode))
win = 1;
break;
case 'I':
case 'J':
case 'K':
case 'L':
case 'M':
case 'N':
case 'O':
case 'P':
if (GET_CODE (op) == CONST_INT
&& CONST_OK_FOR_LETTER_P (INTVAL (op), c))
win = 1;
break;
case 'X':
win = 1;
break;
if (*p == 0)
{
p = next;
next = 0;
}
switch (*p)
{
case '=':
case '?':
case '#':
case '&':
case '!':
case '%':
case 'E':
case 'F':
case 'G':
case 'H':
case 'i':
case 'n':
case 's':
case 'p':
case ',':
case 'I':
case 'J':
case 'K':
case 'L':
case 'M':
case 'N':
case 'O':
case 'P':
#ifdef EXTRA_CONSTRAINT #ifdef EXTRA_CONSTRAINT
case 'Q': case 'Q':
case 'R': case 'R':
case 'S': case 'S':
case 'T': case 'T':
case 'U': case 'U':
if (EXTRA_CONSTRAINT (op, c))
win = 1;
break;
#endif #endif
case 'V':
case 'X': case 'g':
break; if (GET_CODE (op) == MEM
|| (CONSTANT_P (op)
case '+': #ifdef LEGITIMATE_PIC_OPERAND_P
/* An input-output operand is twice as costly if it loses. */ && (! flag_pic || LEGITIMATE_PIC_OPERAND_P (op))
double_cost = 1; #endif
break; ))
win = 1;
case 'm': allows_mem = 1;
case 'o': case 'r':
memok = 1; classes[i]
break; = reg_class_subunion[(int) classes[i]][(int) GENERAL_REGS];
break;
/* * means ignore following letter
when choosing register preferences. */ default:
case '*': classes[i]
p++; = reg_class_subunion[(int) classes[i]]
break; [(int) REG_CLASS_FROM_LETTER (c)];
}
case 'g':
case 'r': constraints[i] = p;
new_class = GENERAL_REGS;
break; /* How we account for this operand now depends on whether it is a
pseudo register or not. If it is, we first check if any
case '0': register classes are valid. If not, we ignore this alternative,
case '1': since we want to assume that all pseudos get allocated for
case '2': register preferencing. If some register class is valid, compute
case '3': the costs of moving the pseudo into that class. */
case '4':
/* If constraint says "match another operand", if (GET_CODE (op) == REG && REGNO (op) >= FIRST_PSEUDO_REGISTER)
use that operand's constraint to choose preferences. */
if (*p - '0' < opno)
{ {
opno = *p - '0'; if (classes[i] == NO_REGS)
next = constraints[opno]; alt_fail = 1;
else
{
struct costs *pp = &this_op_costs[i];
for (class = 0; class < N_REG_CLASSES; class++)
pp->cost[class] = may_move_cost[class][(int) classes[i]];
/* If the alternative actually allows memory, make things
a bit cheaper since we won't need an extra insn to
load it. */
pp->mem_cost = MEMORY_MOVE_COST (mode) - allows_mem;
/* If we have assigned a class to this register in our
first pass, add a cost to this alternative corresponding
to what we would add if this register were not in the
appropriate class. */
if (prefclass)
alt_cost
+= may_move_cost[prefclass[REGNO (op)]][(int) classes[i]];
}
} }
break;
default: /* Otherwise, if this alternative wins, either because we
new_class = REG_CLASS_FROM_LETTER (*p); have already determined that or if we have a hard register of
break; the proper class, there is no cost for this alternative. */
}
/* If this object can fit into the class requested, compute the subunion else if (win
of the requested class and classes found so far. */ || (GET_CODE (op) == REG
if (CLASS_MAX_NREGS (new_class, GET_MODE (op)) && reg_fits_class_p (op, classes[i], 0, mode)))
<= reg_class_size[(int) new_class]) ;
class = reg_class_subunion[(int) class][(int) new_class];
}
{ /* If registers are valid, the cost of this alternative includes
register int i; copying the object to and/or from a register. */
register struct savings *pp;
register enum reg_class class1;
int cost = 2 * (1 + double_cost) * loop_depth;
pp = &savings[REGNO (op)];
/* Increment the savings for this reg else if (classes[i] != NO_REGS)
for each class contained in the one the constraint asks for. */ {
if (op_types[i] != OP_WRITE)
alt_cost += copy_cost (op, mode, classes[i], 1);
if (class != NO_REGS && class != ALL_REGS) if (op_types[i] != OP_READ)
{ alt_cost += copy_cost (op, mode, classes[i], 0);
int extracost; }
pp->savings[(int) class] += cost; /* The only other way this alternative can be used is if this is a
for (i = 0; ; i++) constant that could be placed into memory. */
{
class1 = reg_class_subclasses[(int)class][i]; else if (CONSTANT_P (op) && allows_mem)
if (class1 == LIM_REG_CLASSES) alt_cost += MEMORY_MOVE_COST (mode);
break; else
pp->savings[(int) class1] += cost; alt_fail = 1;
} }
/* If it's slow to move data between this class and GENERAL_REGS,
record that fact. */ if (alt_fail)
extracost = (REGISTER_MOVE_COST (class, GENERAL_REGS) - 2) * loop_depth; continue;
if (extracost > 0)
/* Finally, update the costs with the information we've calculated
about this alternative. */
for (i = 0; i < n_ops; i++)
if (GET_CODE (ops[i]) == REG
&& REGNO (ops[i]) >= FIRST_PSEUDO_REGISTER)
{ {
/* Check that this class and GENERAL_REGS don't overlap. struct costs *pp = &op_costs[i], *qq = &this_op_costs[i];
REGISTER_MOVE_COST is meaningless if there is overlap. */ int scale = 1 + (op_types[i] == OP_READ_WRITE);
HARD_REG_SET temp;
COMPL_HARD_REG_SET (temp, reg_class_contents[(int) class]);
GO_IF_HARD_REG_SUBSET (reg_class_contents[(int) GENERAL_REGS],
temp, label1);
/* Overlap. */
goto label2;
label1: /* No overlap. */
/* Charge this extra cost to GENERAL_REGS
and all its subclasses (none of which overlap this class). */
extracost = extracost * cost / (2 * loop_depth);
pp->savings[(int) GENERAL_REGS] -= extracost;
for (i = 0; ; i++)
{
class1 = reg_class_subclasses[(int)GENERAL_REGS][i];
if (class1 == LIM_REG_CLASSES)
break;
pp->savings[(int) class1] -= extracost;
}
label2: ; pp->mem_cost = MIN (pp->mem_cost,
} (qq->mem_cost + alt_cost) * scale);
}
if (! memok) for (class = 0; class < N_REG_CLASSES; class++)
pp->memcost += (MEMORY_MOVE_COST (GET_MODE (op)) * (1 + double_cost) pp->cost[class] = MIN (pp->cost[class],
- 1) * loop_depth; (qq->cost[class] + alt_cost) * scale);
pp->nrefs += loop_depth; }
} }
} }
/* Compute the cost of loading X into (if TO_P is non-zero) or from (if
TO_P is zero) a register of class CLASS in mode MODE.
X must not be a pseudo. */
static int
copy_cost (x, mode, class, to_p)
rtx x;
enum machine_mode mode;
enum reg_class class;
int to_p;
{
enum reg_class secondary_class = NO_REGS;
/* If X is a SCRATCH, there is actually nothing to move since we are
assuming optimal allocation. */
if (GET_CODE (x) == SCRATCH)
return 0;
/* Get the class we will actually use for a reload. */
class = PREFERRED_RELOAD_CLASS (x, class);
#ifdef HAVE_SECONDARY_RELOADS
/* If we need a secondary reload (we assume here that we are using
the secondary reload as an intermediate, not a scratch register), the
cost is that to load the input into the intermediate register, then
to copy them. We use a special value of TO_P to avoid recursion. */
#ifdef SECONDARY_INPUT_RELOAD_CLASS
if (to_p == 1)
secondary_class = SECONDARY_INPUT_RELOAD_CLASS (class, mode, x);
#endif
#ifdef SECONARY_OUTPUT_RELOAD_CLASS
if (! to_p)
secondary_class = SECONDARY_OUTPUT_RELOAD_CLASS (class, mode, x);
#endif
if (secondary_class != NO_REGS)
return (move_cost[(int) secondary_class][(int) class]
+ copy_cost (x, mode, secondary_class, 2));
#endif /* HAVE_SECONARY_RELOADS */
/* For memory, use the memory move cost, for (hard) registers, use the
cost to move between the register classes, and use 2 for everything
else (constants). */
if (GET_CODE (x) == MEM || class == NO_REGS)
return MEMORY_MOVE_COST (mode);
else if (GET_CODE (x) == REG)
return move_cost[(int) REGNO_REG_CLASS (REGNO (x))][(int) class];
else
/* If this is a constant, we may eventually want to call rtx_cost here. */
return 2;
}
/* Record the pseudo registers we must reload into hard registers /* Record the pseudo registers we must reload into hard registers
in a subexpression of a memory address, X. in a subexpression of a memory address, X.
BCOST is the cost if X is a register and it fails to be in BASE_REG_CLASS.
ICOST is the cost if it fails to be in INDEX_REG_CLASS. */ CLASS is the class that the register needs to be in and is either
BASE_REG_CLASS or INDEX_REG_CLASS.
SCALE is twice the amount to multiply the cost by (it is twice so we
can represent half-cost adjustments). */
void void
record_address_regs (x, bcost, icost) record_address_regs (x, class, scale)
rtx x; rtx x;
int bcost, icost; enum reg_class class;
int scale;
{ {
register enum rtx_code code = GET_CODE (x); register enum rtx_code code = GET_CODE (x);
...@@ -820,66 +1233,88 @@ record_address_regs (x, bcost, icost) ...@@ -820,66 +1233,88 @@ record_address_regs (x, bcost, icost)
we must determine whether registers are "base" or "index" regs. we must determine whether registers are "base" or "index" regs.
If there is a sum of two registers, we must choose one to be If there is a sum of two registers, we must choose one to be
the "base". Luckily, we can use the REGNO_POINTER_FLAG the "base". Luckily, we can use the REGNO_POINTER_FLAG
to make a good choice most of the time. */ to make a good choice most of the time. We only need to do this
on machines that can have two registers in an address and where
the base and index register classes are different.
??? This code used to set REGNO_POINTER_FLAG in some cases, but
that seems bogus since it should only be set when we are sure
the register is being used as a pointer. */
{ {
rtx arg0 = XEXP (x, 0); rtx arg0 = XEXP (x, 0);
rtx arg1 = XEXP (x, 1); rtx arg1 = XEXP (x, 1);
register enum rtx_code code0 = GET_CODE (arg0); register enum rtx_code code0 = GET_CODE (arg0);
register enum rtx_code code1 = GET_CODE (arg1); register enum rtx_code code1 = GET_CODE (arg1);
int icost0 = 0;
int icost1 = 0;
int suppress1 = 0;
int suppress0 = 0;
/* Look inside subregs. */ /* Look inside subregs. */
while (code0 == SUBREG) if (code0 == SUBREG)
arg0 = SUBREG_REG (arg0), code0 = GET_CODE (arg0); arg0 = SUBREG_REG (arg0), code0 = GET_CODE (arg0);
while (code1 == SUBREG) if (code1 == SUBREG)
arg1 = SUBREG_REG (arg1), code1 = GET_CODE (arg1); arg1 = SUBREG_REG (arg1), code1 = GET_CODE (arg1);
if (code0 == MULT || code1 == MEM) /* If this machine only allows one register per address, it must
icost0 = 2; be in the first operand. */
else if (code1 == MULT || code0 == MEM)
icost1 = 2; if (MAX_REGS_PER_ADDRESS == 1)
else if (code0 == CONST_INT) record_address_regs (arg0, class, scale);
suppress0 = 1;
else if (code1 == CONST_INT) /* If index and base registers are the same on this machine, just
suppress1 = 1; record registers in any non-constant operands. We assume here,
else if (code0 == REG && code1 == REG) as well as in the tests below, that all addresses are in
canonical form. */
else if (INDEX_REG_CLASS == BASE_REG_CLASS)
{ {
if (REGNO_POINTER_FLAG (REGNO (arg0))) record_address_regs (arg0, class, scale);
icost1 = 2; if (! CONSTANT_P (arg1))
else if (REGNO_POINTER_FLAG (REGNO (arg1))) record_address_regs (arg1, class, scale);
icost0 = 2;
else
icost0 = icost1 = 1;
} }
else if (code0 == REG)
/* If the second operand is a constant integer, it doesn't change
what class the first operand must be. */
else if (code1 == CONST_INT || code1 == CONST_DOUBLE)
record_address_regs (arg0, class, scale);
/* If the second operand is a symbolic constant, the first operand
must be an index register. */
else if (code1 == SYMBOL_REF || code1 == CONST || code1 == LABEL_REF)
record_address_regs (arg0, INDEX_REG_CLASS, scale);
/* If this the sum of two registers where the first is known to be a
pointer, it must be a base register with the second an index. */
else if (code0 == REG && code1 == REG
&& REGNO_POINTER_FLAG (REGNO (arg0)))
{ {
if (code1 == PLUS record_address_regs (arg0, BASE_REG_CLASS, scale);
&& ! REGNO_POINTER_FLAG (REGNO (arg0))) record_address_regs (arg1, INDEX_REG_CLASS, scale);
icost0 = 2;
else
REGNO_POINTER_FLAG (REGNO (arg0)) = 1;
} }
else if (code1 == REG)
/* If this is the sum of two registers and neither is known to
be a pointer, count equal chances that each might be a base
or index register. This case should be rare. */
else if (code0 == REG && code1 == REG
&& ! REGNO_POINTER_FLAG (REGNO (arg0))
&& ! REGNO_POINTER_FLAG (REGNO (arg1)))
{ {
if (code0 == PLUS record_address_regs (arg0, BASE_REG_CLASS, scale / 2);
&& ! REGNO_POINTER_FLAG (REGNO (arg1))) record_address_regs (arg0, INDEX_REG_CLASS, scale / 2);
icost1 = 2; record_address_regs (arg1, BASE_REG_CLASS, scale / 2);
else record_address_regs (arg1, INDEX_REG_CLASS, scale / 2);
REGNO_POINTER_FLAG (REGNO (arg1)) = 1;
} }
/* ICOST0 determines whether we are treating operand 0 /* In all other cases, the first operand is an index and the
as a base register or as an index register. second is the base. */
SUPPRESS0 nonzero means it isn't a register at all.
ICOST1 and SUPPRESS1 are likewise for operand 1. */
if (! suppress0) else
record_address_regs (arg0, 2 - icost0, icost0); {
if (! suppress1) record_address_regs (arg0, INDEX_REG_CLASS, scale);
record_address_regs (arg1, 2 - icost1, icost1); record_address_regs (arg1, BASE_REG_CLASS, scale);
}
} }
break; break;
...@@ -890,51 +1325,19 @@ record_address_regs (x, bcost, icost) ...@@ -890,51 +1325,19 @@ record_address_regs (x, bcost, icost)
/* Double the importance of a pseudo register that is incremented /* Double the importance of a pseudo register that is incremented
or decremented, since it would take two extra insns or decremented, since it would take two extra insns
if it ends up in the wrong place. */ if it ends up in the wrong place. */
record_address_regs (XEXP (x, 0), 2 * bcost, 2 * icost);
record_address_regs (XEXP (x, 0), class, 2 * scale);
break; break;
case REG: case REG:
{ {
register struct savings *pp; register struct costs *pp = &costs[REGNO (x)];
register enum reg_class class, class1; register int i;
pp = &savings[REGNO (x)];
pp->nrefs += loop_depth;
/* We have an address (or part of one) that is just one register. */
/* Record BCOST worth of savings for classes contained
in BASE_REG_CLASS. */
class = BASE_REG_CLASS;
if (class != NO_REGS && class != ALL_REGS)
{
register int i;
pp->savings[(int) class] += bcost * loop_depth;
for (i = 0; ; i++)
{
class1 = reg_class_subclasses[(int)class][i];
if (class1 == LIM_REG_CLASSES)
break;
pp->savings[(int) class1] += bcost * loop_depth;
}
}
/* Record ICOST worth of savings for classes contained pp->mem_cost += (MEMORY_MOVE_COST (Pmode) * scale) / 2;
in INDEX_REG_CLASS. */
class = INDEX_REG_CLASS; for (i = 0; i < N_REG_CLASSES; i++)
if (icost != 0 && class != NO_REGS && class != ALL_REGS) pp->cost[i] += (may_move_cost[i][(int) class] * scale) / 2;
{
register int i;
pp->savings[(int) class] += icost * loop_depth;
for (i = 0; ; i++)
{
class1 = reg_class_subclasses[(int)class][i];
if (class1 == LIM_REG_CLASSES)
break;
pp->savings[(int) class1] += icost * loop_depth;
}
}
} }
break; break;
...@@ -944,7 +1347,7 @@ record_address_regs (x, bcost, icost) ...@@ -944,7 +1347,7 @@ record_address_regs (x, bcost, icost)
register int i; register int i;
for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
if (fmt[i] == 'e') if (fmt[i] == 'e')
record_address_regs (XEXP (x, i), bcost, icost); record_address_regs (XEXP (x, i), class, scale);
} }
} }
} }
......
gcc/reload.c
...@@ -1502,7 +1502,7 @@ operands_match_p (x, y) ...@@ -1502,7 +1502,7 @@ operands_match_p (x, y)
/* Return the number of times character C occurs in string S. */ /* Return the number of times character C occurs in string S. */
static int int
n_occurrences (c, s) n_occurrences (c, s)
char c; char c;
char *s; char *s;
...@@ -2045,7 +2045,7 @@ find_reloads (insn, replace, ind_levels, live_known, reload_reg_p) ...@@ -2045,7 +2045,7 @@ find_reloads (insn, replace, ind_levels, live_known, reload_reg_p)
? reg_preferred_class (REGNO (recog_operand[i])) : NO_REGS); ? reg_preferred_class (REGNO (recog_operand[i])) : NO_REGS);
pref_or_nothing[i] pref_or_nothing[i]
= (code == REG && REGNO (recog_operand[i]) > FIRST_PSEUDO_REGISTER = (code == REG && REGNO (recog_operand[i]) > FIRST_PSEUDO_REGISTER
&& reg_preferred_or_nothing (REGNO (recog_operand[i]))); && reg_alternate_class (REGNO (recog_operand[i])) == NO_REGS);
} }
/* If this is simply a copy from operand 1 to operand 0, merge the /* If this is simply a copy from operand 1 to operand 0, merge the
......
gcc/rtl.h
...@@ -642,6 +642,7 @@ extern char *decode_asm_operands (); ...@@ -642,6 +642,7 @@ extern char *decode_asm_operands ();
#ifdef BITS_PER_WORD #ifdef BITS_PER_WORD
/* Conditional is to detect when config.h has been included. */ /* Conditional is to detect when config.h has been included. */
extern enum reg_class reg_preferred_class (); extern enum reg_class reg_preferred_class ();
extern enum reg_class reg_alternate_class ();
#endif #endif
extern rtx get_first_nonparm_insn (); extern rtx get_first_nonparm_insn ();
......
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