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-rw-r--r--gcc/expr.c95
1 files changed, 70 insertions, 25 deletions
diff --git a/gcc/expr.c b/gcc/expr.c
index 1fd2afb..42e305d 100644
--- a/gcc/expr.c
+++ b/gcc/expr.c
@@ -210,6 +210,13 @@ static char direct_store[NUM_MACHINE_MODES];
#endif
#endif
+/* This macro is used to determine whether move_by_pieces should be called
+ to perform a structure copy. */
+#ifndef MOVE_BY_PIECES_P
+#define MOVE_BY_PIECES_P(SIZE, ALIGN) (move_by_pieces_ninsns \
+ (SIZE, ALIGN) < MOVE_RATIO)
+#endif
+
/* This array records the insn_code of insns to perform block moves. */
enum insn_code movstr_optab[NUM_MACHINE_MODES];
@@ -1383,6 +1390,38 @@ convert_modes (mode, oldmode, x, unsignedp)
return temp;
}
+
+/* This macro is used to determine what the largest unit size that
+ move_by_pieces can use is. */
+
+/* MOVE_MAX_PIECES is the number of bytes at a time which we can
+ move efficiently, as opposed to MOVE_MAX which is the maximum
+ number of bhytes we can move with a single instruction. */
+
+#ifndef MOVE_MAX_PIECES
+#define MOVE_MAX_PIECES MOVE_MAX
+#endif
+
+/* Some architectures do not have complete pre/post increment/decrement
+ instruction sets, or only move some modes efficiently. these macros
+ allow us to fine tune move_by_pieces for these targets. */
+
+#ifndef USE_LOAD_POST_INCREMENT
+#define USE_LOAD_POST_INCREMENT(MODE) HAVE_POST_INCREMENT
+#endif
+
+#ifndef USE_LOAD_PRE_DECREMENT
+#define USE_LOAD_PRE_DECREMENT(MODE) HAVE_PRE_DECREMENT
+#endif
+
+#ifndef USE_STORE_POST_INCREMENT
+#define USE_STORE_POST_INCREMENT(MODE) HAVE_POST_INCREMENT
+#endif
+
+#ifndef USE_STORE_PRE_DECREMENT
+#define USE_STORE_PRE_DECREMENT(MODE) HAVE_PRE_DECREMENT
+#endif
+
/* Generate several move instructions to copy LEN bytes
from block FROM to block TO. (These are MEM rtx's with BLKmode).
The caller must pass FROM and TO
@@ -1396,7 +1435,9 @@ move_by_pieces (to, from, len, align)
{
struct move_by_pieces data;
rtx to_addr = XEXP (to, 0), from_addr = XEXP (from, 0);
- int max_size = MOVE_MAX + 1;
+ int max_size = MOVE_MAX_PIECES + 1;
+ enum machine_mode mode = VOIDmode, tmode;
+ enum insn_code icode;
data.offset = 0;
data.to_addr = to_addr;
@@ -1427,13 +1468,19 @@ move_by_pieces (to, from, len, align)
if (!(data.autinc_from && data.autinc_to)
&& move_by_pieces_ninsns (len, align) > 2)
{
- if (HAVE_PRE_DECREMENT && data.reverse && ! data.autinc_from)
+ /* Find the mode of the largest move... */
+ for (tmode = GET_CLASS_NARROWEST_MODE (MODE_INT);
+ tmode != VOIDmode; tmode = GET_MODE_WIDER_MODE (tmode))
+ if (GET_MODE_SIZE (tmode) < max_size)
+ mode = tmode;
+
+ if (USE_LOAD_PRE_DECREMENT (mode) && data.reverse && ! data.autinc_from)
{
data.from_addr = copy_addr_to_reg (plus_constant (from_addr, len));
data.autinc_from = 1;
data.explicit_inc_from = -1;
}
- if (HAVE_POST_INCREMENT && ! data.autinc_from)
+ if (USE_LOAD_POST_INCREMENT (mode) && ! data.autinc_from)
{
data.from_addr = copy_addr_to_reg (from_addr);
data.autinc_from = 1;
@@ -1441,13 +1488,13 @@ move_by_pieces (to, from, len, align)
}
if (!data.autinc_from && CONSTANT_P (from_addr))
data.from_addr = copy_addr_to_reg (from_addr);
- if (HAVE_PRE_DECREMENT && data.reverse && ! data.autinc_to)
+ if (USE_STORE_PRE_DECREMENT (mode) && data.reverse && ! data.autinc_to)
{
data.to_addr = copy_addr_to_reg (plus_constant (to_addr, len));
data.autinc_to = 1;
data.explicit_inc_to = -1;
}
- if (HAVE_POST_INCREMENT && ! data.reverse && ! data.autinc_to)
+ if (USE_STORE_POST_INCREMENT (mode) && ! data.reverse && ! data.autinc_to)
{
data.to_addr = copy_addr_to_reg (to_addr);
data.autinc_to = 1;
@@ -1466,9 +1513,6 @@ move_by_pieces (to, from, len, align)
while (max_size > 1)
{
- enum machine_mode mode = VOIDmode, tmode;
- enum insn_code icode;
-
for (tmode = GET_CLASS_NARROWEST_MODE (MODE_INT);
tmode != VOIDmode; tmode = GET_MODE_WIDER_MODE (tmode))
if (GET_MODE_SIZE (tmode) < max_size)
@@ -1622,8 +1666,7 @@ emit_block_move (x, y, size, align)
if (size == 0)
abort ();
- if (GET_CODE (size) == CONST_INT
- && (move_by_pieces_ninsns (INTVAL (size), align) < MOVE_RATIO))
+ if (GET_CODE (size) == CONST_INT && MOVE_BY_PIECES_P (INTVAL (size), align))
move_by_pieces (x, y, INTVAL (size), align);
else
{
@@ -2217,7 +2260,9 @@ clear_by_pieces (to, len, align)
{
struct clear_by_pieces data;
rtx to_addr = XEXP (to, 0);
- int max_size = MOVE_MAX + 1;
+ int max_size = MOVE_MAX_PIECES + 1;
+ enum machine_mode mode = VOIDmode, tmode;
+ enum insn_code icode;
data.offset = 0;
data.to_addr = to_addr;
@@ -2240,13 +2285,19 @@ clear_by_pieces (to, len, align)
if (!data.autinc_to
&& move_by_pieces_ninsns (len, align) > 2)
{
- if (HAVE_PRE_DECREMENT && data.reverse && ! data.autinc_to)
+ /* Determine the main mode we'll be using */
+ for (tmode = GET_CLASS_NARROWEST_MODE (MODE_INT);
+ tmode != VOIDmode; tmode = GET_MODE_WIDER_MODE (tmode))
+ if (GET_MODE_SIZE (tmode) < max_size)
+ mode = tmode;
+
+ if (USE_STORE_PRE_DECREMENT (mode) && data.reverse && ! data.autinc_to)
{
data.to_addr = copy_addr_to_reg (plus_constant (to_addr, len));
data.autinc_to = 1;
data.explicit_inc_to = -1;
}
- if (HAVE_POST_INCREMENT && ! data.reverse && ! data.autinc_to)
+ if (USE_STORE_POST_INCREMENT (mode) && ! data.reverse && ! data.autinc_to)
{
data.to_addr = copy_addr_to_reg (to_addr);
data.autinc_to = 1;
@@ -2265,9 +2316,6 @@ clear_by_pieces (to, len, align)
while (max_size > 1)
{
- enum machine_mode mode = VOIDmode, tmode;
- enum insn_code icode;
-
for (tmode = GET_CLASS_NARROWEST_MODE (MODE_INT);
tmode != VOIDmode; tmode = GET_MODE_WIDER_MODE (tmode))
if (GET_MODE_SIZE (tmode) < max_size)
@@ -2351,7 +2399,7 @@ clear_storage (object, size, align)
size = protect_from_queue (size, 0);
if (GET_CODE (size) == CONST_INT
- && (move_by_pieces_ninsns (INTVAL (size), align) < MOVE_RATIO))
+ && MOVE_BY_PIECES_P (INTVAL (size), align))
clear_by_pieces (object, INTVAL (size), align);
else
@@ -2839,8 +2887,7 @@ emit_push_insn (x, mode, type, size, align, partial, reg, extra,
if (args_addr == 0
&& GET_CODE (size) == CONST_INT
&& skip == 0
- && (move_by_pieces_ninsns ((unsigned) INTVAL (size) - used, align)
- < MOVE_RATIO)
+ && (MOVE_BY_PIECES_P ((unsigned) INTVAL (size) - used, align)))
/* Here we avoid the case of a structure whose weak alignment
forces many pushes of a small amount of data,
and such small pushes do rounding that causes trouble. */
@@ -2938,8 +2985,7 @@ emit_push_insn (x, mode, type, size, align, partial, reg, extra,
/* TEMP is the address of the block. Copy the data there. */
if (GET_CODE (size) == CONST_INT
- && (move_by_pieces_ninsns ((unsigned) INTVAL (size), align)
- < MOVE_RATIO))
+ && (MOVE_BY_PIECES_P ((unsigned) INTVAL (size), align)))
{
move_by_pieces (gen_rtx_MEM (BLKmode, temp), xinner,
INTVAL (size), align);
@@ -6048,10 +6094,9 @@ expand_expr (exp, target, tmode, modifier)
&& ! (target != 0 && safe_from_p (target, exp, 1)))
|| TREE_ADDRESSABLE (exp)
|| (TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST
- && (move_by_pieces_ninsns
- (TREE_INT_CST_LOW (TYPE_SIZE (type))/BITS_PER_UNIT,
- TYPE_ALIGN (type) / BITS_PER_UNIT)
- >= MOVE_RATIO)
+ && (!MOVE_BY_PIECES_P
+ (TREE_INT_CST_LOW (TYPE_SIZE (type))/BITS_PER_UNIT,
+ TYPE_ALIGN (type) / BITS_PER_UNIT))
&& ! mostly_zeros_p (exp))))
|| (modifier == EXPAND_INITIALIZER && TREE_CONSTANT (exp)))
{
generated by cgit v1.1 at 2025-08-09 17:29:15 +0000