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riscv-gcc-1
Commit 1941069a by Paolo Bonzini Committed by Paolo Bonzini
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simplify-rtx.c (simplify_plus_minus): Remove final parameter. 

2005-11-30  Paolo Bonzini  <bonzini@gnu.org>

	* simplify-rtx.c (simplify_plus_minus): Remove final parameter.
	Always produce an output if we can remove NEGs or canonicalize
	(minus (minus ...)) expressions.  Provide a fast path for the
	two-operand case.
	(simplify_gen_binary): Do not call simplify_plus_minus.
	(simplify_binary_operation_1): Reassociate at the end of the
	function.

From-SVN: r107702
parent 77bfa778
Showing with 62 additions and 44 deletions
gcc/ChangeLog
2005-11-30 Paolo Bonzini <bonzini@gnu.org>
* simplify-rtx.c (simplify_plus_minus): Remove final parameter.
Always produce an output if we can remove NEGs or canonicalize
(minus (minus ...)) expressions. Provide a fast path for the
two-operand case.
(simplify_gen_binary): Do not call simplify_plus_minus.
(simplify_binary_operation_1): Reassociate at the end of the
function.
2005-11-29 Evan Cheng <evan.cheng@apple.com>
* config/i386/xmmintrin.h (_MM_TRANSPOSE4_PS): Rewrite using high/low
......
gcc/simplify-rtx.c
......@@ -52,8 +52,7 @@ Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
static rtx neg_const_int (enum machine_mode, rtx);
static bool plus_minus_operand_p (rtx);
static int simplify_plus_minus_op_data_cmp (const void *, const void *);
static rtx simplify_plus_minus (enum rtx_code, enum machine_mode, rtx,
rtx, int);
static rtx simplify_plus_minus (enum rtx_code, enum machine_mode, rtx, rtx);
static rtx simplify_immed_subreg (enum machine_mode, rtx, enum machine_mode,
unsigned int);
static rtx simplify_associative_operation (enum rtx_code, enum machine_mode,
......@@ -125,16 +124,6 @@ simplify_gen_binary (enum rtx_code code, enum machine_mode mode, rtx op0,
if (tem)
return tem;
/* Handle addition and subtraction specially. Otherwise, just form
the operation. */
if (code == PLUS || code == MINUS)
{
tem = simplify_plus_minus (code, mode, op0, op1, 1);
if (tem)
return tem;
}
return gen_rtx_fmt_ee (code, mode, op0, op1);
}
......@@ -1366,7 +1355,7 @@ simplify_binary_operation_1 (enum rtx_code code, enum machine_mode mode,
if (INTEGRAL_MODE_P (mode)
&& (plus_minus_operand_p (op0)
|| plus_minus_operand_p (op1))
&& (tem = simplify_plus_minus (code, mode, op0, op1, 0)) != 0)
&& (tem = simplify_plus_minus (code, mode, op0, op1)) != 0)
return tem;
/* Reassociate floating point addition only when the user
......@@ -1531,18 +1520,6 @@ simplify_binary_operation_1 (enum rtx_code code, enum machine_mode mode,
return simplify_gen_binary (MINUS, mode, tem, XEXP (op0, 0));
}
/* If one of the operands is a PLUS or a MINUS, see if we can
simplify this by the associative law.
Don't use the associative law for floating point.
The inaccuracy makes it nonassociative,
and subtle programs can break if operations are associated. */
if (INTEGRAL_MODE_P (mode)
&& (plus_minus_operand_p (op0)
|| plus_minus_operand_p (op1))
&& (tem = simplify_plus_minus (code, mode, op0, op1, 0)) != 0)
return tem;
/* Don't let a relocatable value get a negative coeff. */
if (GET_CODE (op1) == CONST_INT && GET_MODE (op0) != VOIDmode)
return simplify_gen_binary (PLUS, mode,
......@@ -1565,6 +1542,19 @@ simplify_binary_operation_1 (enum rtx_code code, enum machine_mode mode,
return simplify_gen_binary (AND, mode, op0, tem);
}
}
/* If one of the operands is a PLUS or a MINUS, see if we can
simplify this by the associative law. This will, for example,
canonicalize (minus A (plus B C)) to (minus (minus A B) C).
Don't use the associative law for floating point.
The inaccuracy makes it nonassociative,
and subtle programs can break if operations are associated. */
if (INTEGRAL_MODE_P (mode)
&& (plus_minus_operand_p (op0)
|| plus_minus_operand_p (op1))
&& (tem = simplify_plus_minus (code, mode, op0, op1)) != 0)
return tem;
break;
case MULT:
......@@ -2583,12 +2573,7 @@ simplify_const_binary_operation (enum rtx_code code, enum machine_mode mode,
Rather than test for specific case, we do this by a brute-force method
and do all possible simplifications until no more changes occur. Then
we rebuild the operation.
If FORCE is true, then always generate the rtx. This is used to
canonicalize stuff emitted from simplify_gen_binary. Note that this
can still fail if the rtx is too complex. It won't fail just because
the result is not 'simpler' than the input, however. */
we rebuild the operation. */
struct simplify_plus_minus_op_data
{
......@@ -2613,12 +2598,12 @@ simplify_plus_minus_op_data_cmp (const void *p1, const void *p2)
static rtx
simplify_plus_minus (enum rtx_code code, enum machine_mode mode, rtx op0,
rtx op1, int force)
rtx op1)
{
struct simplify_plus_minus_op_data ops[8];
rtx result, tem;
int n_ops = 2, input_ops = 2, input_consts = 0, n_consts;
int first, changed;
int first, changed, canonicalized = 0;
int i, j;
memset (ops, 0, sizeof ops);
......@@ -2656,12 +2641,14 @@ simplify_plus_minus (enum rtx_code code, enum machine_mode mode, rtx op0,
ops[i].op = XEXP (this_op, 0);
input_ops++;
changed = 1;
canonicalized |= this_neg;
break;
case NEG:
ops[i].op = XEXP (this_op, 0);
ops[i].neg = ! this_neg;
changed = 1;
canonicalized = 1;
break;
case CONST:
......@@ -2676,6 +2663,7 @@ simplify_plus_minus (enum rtx_code code, enum machine_mode mode, rtx op0,
n_ops++;
input_consts++;
changed = 1;
canonicalized = 1;
}
break;
......@@ -2688,6 +2676,7 @@ simplify_plus_minus (enum rtx_code code, enum machine_mode mode, rtx op0,
ops[i].op = XEXP (this_op, 0);
ops[i].neg = !this_neg;
changed = 1;
canonicalized = 1;
}
break;
......@@ -2697,6 +2686,7 @@ simplify_plus_minus (enum rtx_code code, enum machine_mode mode, rtx op0,
ops[i].op = neg_const_int (mode, this_op);
ops[i].neg = 0;
changed = 1;
canonicalized = 1;
}
break;
......@@ -2707,10 +2697,37 @@ simplify_plus_minus (enum rtx_code code, enum machine_mode mode, rtx op0,
}
while (changed);
/* If we only have two operands, we can't do anything. */
if (n_ops <= 2 && !force)
gcc_assert (n_ops >= 2);
if (!canonicalized)
return NULL_RTX;
/* If we only have two operands, we can avoid the loops. */
if (n_ops == 2)
{
enum rtx_code code = ops[0].neg || ops[1].neg ? MINUS : PLUS;
rtx lhs, rhs;
/* Get the two operands. Be careful with the order, especially for
the cases where code == MINUS. */
if (ops[0].neg && ops[1].neg)
{
lhs = gen_rtx_NEG (mode, ops[0].op);
rhs = ops[1].op;
}
else if (ops[0].neg)
{
lhs = ops[1].op;
rhs = ops[0].op;
}
else
{
lhs = ops[0].op;
rhs = ops[1].op;
}
return simplify_const_binary_operation (code, mode, lhs, rhs);
}
/* Count the number of CONSTs we didn't split above. */
for (i = 0; i < n_ops; i++)
if (GET_CODE (ops[i].op) == CONST)
......@@ -2824,15 +2841,6 @@ simplify_plus_minus (enum rtx_code code, enum machine_mode mode, rtx op0,
if (GET_CODE (ops[i].op) == CONST)
n_consts++;
/* Give up if we didn't reduce the number of operands we had. Make
sure we count a CONST as two operands. If we have the same
number of operands, but have made more CONSTs than before, this
is also an improvement, so accept it. */
if (!force
&& (n_ops + n_consts > input_ops
|| (n_ops + n_consts == input_ops && n_consts <= input_consts)))
return NULL_RTX;
/* Put a non-negated operand first, if possible. */
for (i = 0; i < n_ops && ops[i].neg; i++)
......
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