/* RTL simplification functions for GNU compiler.
Copyright (C) 1987, 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
- 1999, 2000, 2001, 2002, 2003 Free Software Foundation, Inc.
+ 1999, 2000, 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
This file is part of GCC.
((((HOST_WIDE_INT) low) < 0) ? ((HOST_WIDE_INT) -1) : ((HOST_WIDE_INT) 0))
static rtx neg_const_int (enum machine_mode, rtx);
+static bool mode_signbit_p (enum machine_mode, 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_immed_subreg (enum machine_mode, rtx, enum machine_mode,
+ unsigned int);
+static rtx simplify_associative_operation (enum rtx_code, enum machine_mode,
+ rtx, rtx);
+static rtx simplify_relational_operation_1 (enum rtx_code, enum machine_mode,
+ enum machine_mode, rtx, rtx);
\f
/* Negate a CONST_INT rtx, truncating (because a conversion from a
maximally negative number can overflow). */
return gen_int_mode (- INTVAL (i), mode);
}
+/* Test whether expression, X, is an immediate constant that represents
+ the most significant bit of machine mode MODE. */
+
+static bool
+mode_signbit_p (enum machine_mode mode, rtx x)
+{
+ unsigned HOST_WIDE_INT val;
+ unsigned int width;
+
+ if (GET_MODE_CLASS (mode) != MODE_INT)
+ return false;
+
+ width = GET_MODE_BITSIZE (mode);
+ if (width == 0)
+ return false;
+
+ if (width <= HOST_BITS_PER_WIDE_INT
+ && GET_CODE (x) == CONST_INT)
+ val = INTVAL (x);
+ else if (width <= 2 * HOST_BITS_PER_WIDE_INT
+ && GET_CODE (x) == CONST_DOUBLE
+ && CONST_DOUBLE_LOW (x) == 0)
+ {
+ val = CONST_DOUBLE_HIGH (x);
+ width -= HOST_BITS_PER_WIDE_INT;
+ }
+ else
+ return false;
+
+ if (width < HOST_BITS_PER_WIDE_INT)
+ val &= ((unsigned HOST_WIDE_INT) 1 << width) - 1;
+ return val == ((unsigned HOST_WIDE_INT) 1 << (width - 1));
+}
\f
/* Make a binary operation by properly ordering the operands and
seeing if the expression folds. */
rtx tem;
/* Put complex operands first and constants second if commutative. */
- if (GET_RTX_CLASS (code) == 'c'
+ if (GET_RTX_CLASS (code) == RTX_COMM_ARITH
&& swap_commutative_operands_p (op0, op1))
tem = op0, op0 = op1, op1 = tem;
addr = XEXP (x, 0);
- /* Call target hook to avoid the effects of -fpic etc... */
- addr = (*targetm.delegitimize_address) (addr);
+ /* Call target hook to avoid the effects of -fpic etc.... */
+ addr = targetm.delegitimize_address (addr);
if (GET_CODE (addr) == LO_SUM)
addr = XEXP (addr, 1);
return gen_rtx_fmt_eee (code, mode, op0, op1, op2);
}
-\f
+
/* Likewise, for relational operations.
- CMP_MODE specifies mode comparison is done in.
- */
+ CMP_MODE specifies mode comparison is done in. */
rtx
simplify_gen_relational (enum rtx_code code, enum machine_mode mode,
{
rtx tem;
- if ((tem = simplify_relational_operation (code, cmp_mode, op0, op1)) != 0)
+ if (0 != (tem = simplify_relational_operation (code, mode, cmp_mode,
+ op0, op1)))
return tem;
- /* For the following tests, ensure const0_rtx is op1. */
- if (op0 == const0_rtx && swap_commutative_operands_p (op0, op1))
- tem = op0, op0 = op1, op1 = tem, code = swap_condition (code);
-
- /* If op0 is a compare, extract the comparison arguments from it. */
- if (GET_CODE (op0) == COMPARE && op1 == const0_rtx)
- op1 = XEXP (op0, 1), op0 = XEXP (op0, 0);
-
- /* If op0 is a comparison, extract the comparison arguments form it. */
- if (code == NE && op1 == const0_rtx
- && GET_RTX_CLASS (GET_CODE (op0)) == '<')
- return op0;
- else if (code == EQ && op1 == const0_rtx)
- {
- /* The following tests GET_RTX_CLASS (GET_CODE (op0)) == '<'. */
- enum rtx_code new = reversed_comparison_code (op0, NULL_RTX);
- if (new != UNKNOWN)
- {
- code = new;
- mode = cmp_mode;
- op1 = XEXP (op0, 1);
- op0 = XEXP (op0, 0);
- }
- }
-
- /* Put complex operands first and constants second. */
- if (swap_commutative_operands_p (op0, op1))
- tem = op0, op0 = op1, op1 = tem, code = swap_condition (code);
-
return gen_rtx_fmt_ee (code, mode, op0, op1);
}
\f
{
enum rtx_code code = GET_CODE (x);
enum machine_mode mode = GET_MODE (x);
+ enum machine_mode op_mode;
+ rtx op0, op1, op2;
/* If X is OLD, return NEW. Otherwise, if this is an expression, try
to build a new expression substituting recursively. If we can't do
switch (GET_RTX_CLASS (code))
{
- case '1':
- {
- enum machine_mode op_mode = GET_MODE (XEXP (x, 0));
- rtx op = (XEXP (x, 0) == old
- ? new : simplify_replace_rtx (XEXP (x, 0), old, new));
-
- return simplify_gen_unary (code, mode, op, op_mode);
- }
-
- case '2':
- case 'c':
- return
- simplify_gen_binary (code, mode,
- simplify_replace_rtx (XEXP (x, 0), old, new),
- simplify_replace_rtx (XEXP (x, 1), old, new));
- case '<':
- {
- enum machine_mode op_mode = (GET_MODE (XEXP (x, 0)) != VOIDmode
- ? GET_MODE (XEXP (x, 0))
- : GET_MODE (XEXP (x, 1)));
- rtx op0 = simplify_replace_rtx (XEXP (x, 0), old, new);
- rtx op1 = simplify_replace_rtx (XEXP (x, 1), old, new);
-
- return
- simplify_gen_relational (code, mode,
- (op_mode != VOIDmode
- ? op_mode
- : GET_MODE (op0) != VOIDmode
- ? GET_MODE (op0)
- : GET_MODE (op1)),
- op0, op1);
- }
-
- case '3':
- case 'b':
- {
- enum machine_mode op_mode = GET_MODE (XEXP (x, 0));
- rtx op0 = simplify_replace_rtx (XEXP (x, 0), old, new);
-
- return
- simplify_gen_ternary (code, mode,
- (op_mode != VOIDmode
- ? op_mode
- : GET_MODE (op0)),
- op0,
- simplify_replace_rtx (XEXP (x, 1), old, new),
- simplify_replace_rtx (XEXP (x, 2), old, new));
- }
+ case RTX_UNARY:
+ op0 = XEXP (x, 0);
+ op_mode = GET_MODE (op0);
+ op0 = simplify_replace_rtx (op0, old, new);
+ if (op0 == XEXP (x, 0))
+ return x;
+ return simplify_gen_unary (code, mode, op0, op_mode);
+
+ case RTX_BIN_ARITH:
+ case RTX_COMM_ARITH:
+ op0 = simplify_replace_rtx (XEXP (x, 0), old, new);
+ op1 = simplify_replace_rtx (XEXP (x, 1), old, new);
+ if (op0 == XEXP (x, 0) && op1 == XEXP (x, 1))
+ return x;
+ return simplify_gen_binary (code, mode, op0, op1);
+
+ case RTX_COMPARE:
+ case RTX_COMM_COMPARE:
+ op0 = XEXP (x, 0);
+ op1 = XEXP (x, 1);
+ op_mode = GET_MODE (op0) != VOIDmode ? GET_MODE (op0) : GET_MODE (op1);
+ op0 = simplify_replace_rtx (op0, old, new);
+ op1 = simplify_replace_rtx (op1, old, new);
+ if (op0 == XEXP (x, 0) && op1 == XEXP (x, 1))
+ return x;
+ return simplify_gen_relational (code, mode, op_mode, op0, op1);
+
+ case RTX_TERNARY:
+ case RTX_BITFIELD_OPS:
+ op0 = XEXP (x, 0);
+ op_mode = GET_MODE (op0);
+ op0 = simplify_replace_rtx (op0, old, new);
+ op1 = simplify_replace_rtx (XEXP (x, 1), old, new);
+ op2 = simplify_replace_rtx (XEXP (x, 2), old, new);
+ if (op0 == XEXP (x, 0) && op1 == XEXP (x, 1) && op2 == XEXP (x, 2))
+ return x;
+ if (op_mode == VOIDmode)
+ op_mode = GET_MODE (op0);
+ return simplify_gen_ternary (code, mode, op_mode, op0, op1, op2);
- case 'x':
+ case RTX_EXTRA:
/* The only case we try to handle is a SUBREG. */
if (code == SUBREG)
{
- rtx exp;
- exp = simplify_gen_subreg (GET_MODE (x),
- simplify_replace_rtx (SUBREG_REG (x),
- old, new),
+ op0 = simplify_replace_rtx (SUBREG_REG (x), old, new);
+ if (op0 == SUBREG_REG (x))
+ return x;
+ op0 = simplify_gen_subreg (GET_MODE (x), op0,
GET_MODE (SUBREG_REG (x)),
SUBREG_BYTE (x));
- if (exp)
- x = exp;
+ return op0 ? op0 : x;
}
- return x;
+ break;
- case 'o':
+ case RTX_OBJ:
if (code == MEM)
- return replace_equiv_address_nv (x,
- simplify_replace_rtx (XEXP (x, 0),
- old, new));
+ {
+ op0 = simplify_replace_rtx (XEXP (x, 0), old, new);
+ if (op0 == XEXP (x, 0))
+ return x;
+ return replace_equiv_address_nv (x, op0);
+ }
else if (code == LO_SUM)
{
- rtx op0 = simplify_replace_rtx (XEXP (x, 0), old, new);
- rtx op1 = simplify_replace_rtx (XEXP (x, 1), old, new);
+ op0 = simplify_replace_rtx (XEXP (x, 0), old, new);
+ op1 = simplify_replace_rtx (XEXP (x, 1), old, new);
/* (lo_sum (high x) x) -> x */
if (GET_CODE (op0) == HIGH && rtx_equal_p (XEXP (op0, 0), op1))
return op1;
+ if (op0 == XEXP (x, 0) && op1 == XEXP (x, 1))
+ return x;
return gen_rtx_LO_SUM (mode, op0, op1);
}
else if (code == REG)
if (REG_P (old) && REGNO (x) == REGNO (old))
return new;
}
-
- return x;
+ break;
default:
- return x;
+ break;
}
return x;
}
return gen_rtx_CONST_VECTOR (mode, v);
}
}
+ else if (GET_CODE (op) == CONST)
+ return simplify_unary_operation (code, mode, XEXP (op, 0), op_mode);
if (VECTOR_MODE_P (mode) && GET_CODE (trueop) == CONST_VECTOR)
{
case CLZ:
hv = 0;
- if (h1 == 0)
- lv = GET_MODE_BITSIZE (mode) - floor_log2 (l1) - 1;
- else
+ if (h1 != 0)
lv = GET_MODE_BITSIZE (mode) - floor_log2 (h1) - 1
- HOST_BITS_PER_WIDE_INT;
+ else if (l1 != 0)
+ lv = GET_MODE_BITSIZE (mode) - floor_log2 (l1) - 1;
+ else if (! CLZ_DEFINED_VALUE_AT_ZERO (mode, lv))
+ lv = GET_MODE_BITSIZE (mode);
break;
case CTZ:
hv = 0;
- if (l1 == 0)
- {
- if (h1 == 0)
- lv = GET_MODE_BITSIZE (mode);
- else
- lv = HOST_BITS_PER_WIDE_INT + exact_log2 (h1 & -h1);
- }
- else
+ if (l1 != 0)
lv = exact_log2 (l1 & -l1);
+ else if (h1 != 0)
+ lv = HOST_BITS_PER_WIDE_INT + exact_log2 (h1 & -h1);
+ else if (! CTZ_DEFINED_VALUE_AT_ZERO (mode, lv))
+ lv = GET_MODE_BITSIZE (mode);
break;
case POPCOUNT:
case FIX:
real_arithmetic (&d, FIX_TRUNC_EXPR, &d, NULL);
break;
+ case NOT:
+ {
+ long tmp[4];
+ int i;
+ real_to_target (tmp, &d, GET_MODE (trueop));
+ for (i = 0; i < 4; i++)
+ tmp[i] = ~tmp[i];
+ real_from_target (&d, tmp, mode);
+ }
default:
abort ();
}
else if (GET_CODE (trueop) == CONST_DOUBLE
&& GET_MODE_CLASS (GET_MODE (trueop)) == MODE_FLOAT
&& GET_MODE_CLASS (mode) == MODE_INT
- && width <= HOST_BITS_PER_WIDE_INT && width > 0)
+ && width <= 2*HOST_BITS_PER_WIDE_INT && width > 0)
{
- HOST_WIDE_INT i;
- REAL_VALUE_TYPE d;
- REAL_VALUE_FROM_CONST_DOUBLE (d, trueop);
+ /* Although the overflow semantics of RTL's FIX and UNSIGNED_FIX
+ operators are intentionally left unspecified (to ease implementation
+ by target backends), for consistency, this routine implements the
+ same semantics for constant folding as used by the middle-end. */
+
+ HOST_WIDE_INT xh, xl, th, tl;
+ REAL_VALUE_TYPE x, t;
+ REAL_VALUE_FROM_CONST_DOUBLE (x, trueop);
switch (code)
{
- case FIX: i = REAL_VALUE_FIX (d); break;
- case UNSIGNED_FIX: i = REAL_VALUE_UNSIGNED_FIX (d); break;
+ case FIX:
+ if (REAL_VALUE_ISNAN (x))
+ return const0_rtx;
+
+ /* Test against the signed upper bound. */
+ if (width > HOST_BITS_PER_WIDE_INT)
+ {
+ th = ((unsigned HOST_WIDE_INT) 1
+ << (width - HOST_BITS_PER_WIDE_INT - 1)) - 1;
+ tl = -1;
+ }
+ else
+ {
+ th = 0;
+ tl = ((unsigned HOST_WIDE_INT) 1 << (width - 1)) - 1;
+ }
+ real_from_integer (&t, VOIDmode, tl, th, 0);
+ if (REAL_VALUES_LESS (t, x))
+ {
+ xh = th;
+ xl = tl;
+ break;
+ }
+
+ /* Test against the signed lower bound. */
+ if (width > HOST_BITS_PER_WIDE_INT)
+ {
+ th = (HOST_WIDE_INT) -1 << (width - HOST_BITS_PER_WIDE_INT - 1);
+ tl = 0;
+ }
+ else
+ {
+ th = -1;
+ tl = (HOST_WIDE_INT) -1 << (width - 1);
+ }
+ real_from_integer (&t, VOIDmode, tl, th, 0);
+ if (REAL_VALUES_LESS (x, t))
+ {
+ xh = th;
+ xl = tl;
+ break;
+ }
+ REAL_VALUE_TO_INT (&xl, &xh, x);
+ break;
+
+ case UNSIGNED_FIX:
+ if (REAL_VALUE_ISNAN (x) || REAL_VALUE_NEGATIVE (x))
+ return const0_rtx;
+
+ /* Test against the unsigned upper bound. */
+ if (width == 2*HOST_BITS_PER_WIDE_INT)
+ {
+ th = -1;
+ tl = -1;
+ }
+ else if (width >= HOST_BITS_PER_WIDE_INT)
+ {
+ th = ((unsigned HOST_WIDE_INT) 1
+ << (width - HOST_BITS_PER_WIDE_INT)) - 1;
+ tl = -1;
+ }
+ else
+ {
+ th = 0;
+ tl = ((unsigned HOST_WIDE_INT) 1 << width) - 1;
+ }
+ real_from_integer (&t, VOIDmode, tl, th, 1);
+ if (REAL_VALUES_LESS (t, x))
+ {
+ xh = th;
+ xl = tl;
+ break;
+ }
+
+ REAL_VALUE_TO_INT (&xl, &xh, x);
+ break;
+
default:
abort ();
}
- return gen_int_mode (i, mode);
+ return immed_double_const (xl, xh, mode);
}
/* This was formerly used only for non-IEEE float.
else
{
enum rtx_code reversed;
+ rtx temp;
+
/* There are some simplifications we can do even if the operands
aren't constant. */
switch (code)
return XEXP (op, 0);
/* (not (eq X Y)) == (ne X Y), etc. */
- if (mode == BImode && GET_RTX_CLASS (GET_CODE (op)) == '<'
+ if (COMPARISON_P (op)
+ && (mode == BImode || STORE_FLAG_VALUE == -1)
&& ((reversed = reversed_comparison_code (op, NULL_RTX))
!= UNKNOWN))
- return gen_rtx_fmt_ee (reversed,
- op_mode, XEXP (op, 0), XEXP (op, 1));
+ return simplify_gen_relational (reversed, mode, VOIDmode,
+ XEXP (op, 0), XEXP (op, 1));
+
+ /* (not (plus X -1)) can become (neg X). */
+ if (GET_CODE (op) == PLUS
+ && XEXP (op, 1) == constm1_rtx)
+ return simplify_gen_unary (NEG, mode, XEXP (op, 0), mode);
+
+ /* Similarly, (not (neg X)) is (plus X -1). */
+ if (GET_CODE (op) == NEG)
+ return plus_constant (XEXP (op, 0), -1);
+
+ /* (not (xor X C)) for C constant is (xor X D) with D = ~C. */
+ if (GET_CODE (op) == XOR
+ && GET_CODE (XEXP (op, 1)) == CONST_INT
+ && (temp = simplify_unary_operation (NOT, mode,
+ XEXP (op, 1),
+ mode)) != 0)
+ return simplify_gen_binary (XOR, mode, XEXP (op, 0), temp);
+
+ /* (not (plus X C)) for signbit C is (xor X D) with D = ~C. */
+ if (GET_CODE (op) == PLUS
+ && GET_CODE (XEXP (op, 1)) == CONST_INT
+ && mode_signbit_p (mode, XEXP (op, 1))
+ && (temp = simplify_unary_operation (NOT, mode,
+ XEXP (op, 1),
+ mode)) != 0)
+ return simplify_gen_binary (XOR, mode, XEXP (op, 0), temp);
+
+
+
+ /* (not (ashift 1 X)) is (rotate ~1 X). We used to do this for
+ operands other than 1, but that is not valid. We could do a
+ similar simplification for (not (lshiftrt C X)) where C is
+ just the sign bit, but this doesn't seem common enough to
+ bother with. */
+ if (GET_CODE (op) == ASHIFT
+ && XEXP (op, 0) == const1_rtx)
+ {
+ temp = simplify_gen_unary (NOT, mode, const1_rtx, mode);
+ return simplify_gen_binary (ROTATE, mode, temp, XEXP (op, 1));
+ }
+
+ /* If STORE_FLAG_VALUE is -1, (not (comparison X Y)) can be done
+ by reversing the comparison code if valid. */
+ if (STORE_FLAG_VALUE == -1
+ && COMPARISON_P (op)
+ && (reversed = reversed_comparison_code (op, NULL_RTX))
+ != UNKNOWN)
+ return simplify_gen_relational (reversed, mode, VOIDmode,
+ XEXP (op, 0), XEXP (op, 1));
+
+ /* (not (ashiftrt foo C)) where C is the number of bits in FOO
+ minus 1 is (ge foo (const_int 0)) if STORE_FLAG_VALUE is -1,
+ so we can perform the above simplification. */
+
+ if (STORE_FLAG_VALUE == -1
+ && GET_CODE (op) == ASHIFTRT
+ && GET_CODE (XEXP (op, 1)) == CONST_INT
+ && INTVAL (XEXP (op, 1)) == GET_MODE_BITSIZE (mode) - 1)
+ return simplify_gen_relational (GE, mode, VOIDmode,
+ XEXP (op, 0), const0_rtx);
+
break;
case NEG:
/* (neg (neg X)) == X. */
if (GET_CODE (op) == NEG)
return XEXP (op, 0);
+
+ /* (neg (plus X 1)) can become (not X). */
+ if (GET_CODE (op) == PLUS
+ && XEXP (op, 1) == const1_rtx)
+ return simplify_gen_unary (NOT, mode, XEXP (op, 0), mode);
+
+ /* Similarly, (neg (not X)) is (plus X 1). */
+ if (GET_CODE (op) == NOT)
+ return plus_constant (XEXP (op, 0), 1);
+
+ /* (neg (minus X Y)) can become (minus Y X). This transformation
+ isn't safe for modes with signed zeros, since if X and Y are
+ both +0, (minus Y X) is the same as (minus X Y). If the
+ rounding mode is towards +infinity (or -infinity) then the two
+ expressions will be rounded differently. */
+ if (GET_CODE (op) == MINUS
+ && !HONOR_SIGNED_ZEROS (mode)
+ && !HONOR_SIGN_DEPENDENT_ROUNDING (mode))
+ return simplify_gen_binary (MINUS, mode, XEXP (op, 1),
+ XEXP (op, 0));
+
+ if (GET_CODE (op) == PLUS
+ && !HONOR_SIGNED_ZEROS (mode)
+ && !HONOR_SIGN_DEPENDENT_ROUNDING (mode))
+ {
+ /* (neg (plus A C)) is simplified to (minus -C A). */
+ if (GET_CODE (XEXP (op, 1)) == CONST_INT
+ || GET_CODE (XEXP (op, 1)) == CONST_DOUBLE)
+ {
+ temp = simplify_unary_operation (NEG, mode, XEXP (op, 1),
+ mode);
+ if (temp)
+ return simplify_gen_binary (MINUS, mode, temp,
+ XEXP (op, 0));
+ }
+
+ /* (neg (plus A B)) is canonicalized to (minus (neg A) B). */
+ temp = simplify_gen_unary (NEG, mode, XEXP (op, 0), mode);
+ return simplify_gen_binary (MINUS, mode, temp, XEXP (op, 1));
+ }
+
+ /* (neg (mult A B)) becomes (mult (neg A) B).
+ This works even for floating-point values. */
+ if (GET_CODE (op) == MULT
+ && !HONOR_SIGN_DEPENDENT_ROUNDING (mode))
+ {
+ temp = simplify_gen_unary (NEG, mode, XEXP (op, 0), mode);
+ return simplify_gen_binary (MULT, mode, temp, XEXP (op, 1));
+ }
+
+ /* NEG commutes with ASHIFT since it is multiplication. Only do
+ this if we can then eliminate the NEG (e.g., if the operand
+ is a constant). */
+ if (GET_CODE (op) == ASHIFT)
+ {
+ temp = simplify_unary_operation (NEG, mode, XEXP (op, 0),
+ mode);
+ if (temp)
+ return simplify_gen_binary (ASHIFT, mode, temp,
+ XEXP (op, 1));
+ }
+
+ /* (neg (ashiftrt X C)) can be replaced by (lshiftrt X C) when
+ C is equal to the width of MODE minus 1. */
+ if (GET_CODE (op) == ASHIFTRT
+ && GET_CODE (XEXP (op, 1)) == CONST_INT
+ && INTVAL (XEXP (op, 1)) == GET_MODE_BITSIZE (mode) - 1)
+ return simplify_gen_binary (LSHIFTRT, mode,
+ XEXP (op, 0), XEXP (op, 1));
+
+ /* (neg (lshiftrt X C)) can be replaced by (ashiftrt X C) when
+ C is equal to the width of MODE minus 1. */
+ if (GET_CODE (op) == LSHIFTRT
+ && GET_CODE (XEXP (op, 1)) == CONST_INT
+ && INTVAL (XEXP (op, 1)) == GET_MODE_BITSIZE (mode) - 1)
+ return simplify_gen_binary (ASHIFTRT, mode,
+ XEXP (op, 0), XEXP (op, 1));
+
break;
case SIGN_EXTEND:
&& GET_CODE (XEXP (XEXP (op, 0), 1)) == LABEL_REF)
return XEXP (op, 0);
+ /* Check for a sign extension of a subreg of a promoted
+ variable, where the promotion is sign-extended, and the
+ target mode is the same as the variable's promotion. */
+ if (GET_CODE (op) == SUBREG
+ && SUBREG_PROMOTED_VAR_P (op)
+ && ! SUBREG_PROMOTED_UNSIGNED_P (op)
+ && GET_MODE (XEXP (op, 0)) == mode)
+ return XEXP (op, 0);
+
#if defined(POINTERS_EXTEND_UNSIGNED) && !defined(HAVE_ptr_extend)
if (! POINTERS_EXTEND_UNSIGNED
&& mode == Pmode && GET_MODE (op) == ptr_mode
#endif
break;
-#if defined(POINTERS_EXTEND_UNSIGNED) && !defined(HAVE_ptr_extend)
case ZERO_EXTEND:
+ /* Check for a zero extension of a subreg of a promoted
+ variable, where the promotion is zero-extended, and the
+ target mode is the same as the variable's promotion. */
+ if (GET_CODE (op) == SUBREG
+ && SUBREG_PROMOTED_VAR_P (op)
+ && SUBREG_PROMOTED_UNSIGNED_P (op)
+ && GET_MODE (XEXP (op, 0)) == mode)
+ return XEXP (op, 0);
+
+#if defined(POINTERS_EXTEND_UNSIGNED) && !defined(HAVE_ptr_extend)
if (POINTERS_EXTEND_UNSIGNED > 0
&& mode == Pmode && GET_MODE (op) == ptr_mode
&& (CONSTANT_P (op)
&& REG_POINTER (SUBREG_REG (op))
&& GET_MODE (SUBREG_REG (op)) == Pmode)))
return convert_memory_address (Pmode, op);
- break;
#endif
+ break;
default:
break;
}
}
\f
+/* Subroutine of simplify_binary_operation to simplify a commutative,
+ associative binary operation CODE with result mode MODE, operating
+ on OP0 and OP1. CODE is currently one of PLUS, MULT, AND, IOR, XOR,
+ SMIN, SMAX, UMIN or UMAX. Return zero if no simplification or
+ canonicalization is possible. */
+
+static rtx
+simplify_associative_operation (enum rtx_code code, enum machine_mode mode,
+ rtx op0, rtx op1)
+{
+ rtx tem;
+
+ /* Linearize the operator to the left. */
+ if (GET_CODE (op1) == code)
+ {
+ /* "(a op b) op (c op d)" becomes "((a op b) op c) op d)". */
+ if (GET_CODE (op0) == code)
+ {
+ tem = simplify_gen_binary (code, mode, op0, XEXP (op1, 0));
+ return simplify_gen_binary (code, mode, tem, XEXP (op1, 1));
+ }
+
+ /* "a op (b op c)" becomes "(b op c) op a". */
+ if (! swap_commutative_operands_p (op1, op0))
+ return simplify_gen_binary (code, mode, op1, op0);
+
+ tem = op0;
+ op0 = op1;
+ op1 = tem;
+ }
+
+ if (GET_CODE (op0) == code)
+ {
+ /* Canonicalize "(x op c) op y" as "(x op y) op c". */
+ if (swap_commutative_operands_p (XEXP (op0, 1), op1))
+ {
+ tem = simplify_gen_binary (code, mode, XEXP (op0, 0), op1);
+ return simplify_gen_binary (code, mode, tem, XEXP (op0, 1));
+ }
+
+ /* Attempt to simplify "(a op b) op c" as "a op (b op c)". */
+ tem = swap_commutative_operands_p (XEXP (op0, 1), op1)
+ ? simplify_binary_operation (code, mode, op1, XEXP (op0, 1))
+ : simplify_binary_operation (code, mode, XEXP (op0, 1), op1);
+ if (tem != 0)
+ return simplify_gen_binary (code, mode, XEXP (op0, 0), tem);
+
+ /* Attempt to simplify "(a op b) op c" as "(a op c) op b". */
+ tem = swap_commutative_operands_p (XEXP (op0, 0), op1)
+ ? simplify_binary_operation (code, mode, op1, XEXP (op0, 0))
+ : simplify_binary_operation (code, mode, XEXP (op0, 0), op1);
+ if (tem != 0)
+ return simplify_gen_binary (code, mode, tem, XEXP (op0, 1));
+ }
+
+ return 0;
+}
+
/* Simplify a binary operation CODE with result mode MODE, operating on OP0
and OP1. Return 0 if no simplification is possible.
HOST_WIDE_INT arg0, arg1, arg0s, arg1s;
HOST_WIDE_INT val;
unsigned int width = GET_MODE_BITSIZE (mode);
+ rtx trueop0, trueop1;
rtx tem;
- rtx trueop0 = avoid_constant_pool_reference (op0);
- rtx trueop1 = avoid_constant_pool_reference (op1);
+#ifdef ENABLE_CHECKING
/* Relational operations don't work here. We must know the mode
of the operands in order to do the comparison correctly.
Assuming a full word can give incorrect results.
Consider comparing 128 with -128 in QImode. */
- if (GET_RTX_CLASS (code) == '<')
+ if (GET_RTX_CLASS (code) == RTX_COMPARE
+ || GET_RTX_CLASS (code) == RTX_COMM_COMPARE)
abort ();
+#endif
/* Make sure the constant is second. */
- if (GET_RTX_CLASS (code) == 'c'
- && swap_commutative_operands_p (trueop0, trueop1))
+ if (GET_RTX_CLASS (code) == RTX_COMM_ARITH
+ && swap_commutative_operands_p (op0, op1))
{
tem = op0, op0 = op1, op1 = tem;
- tem = trueop0, trueop0 = trueop1, trueop1 = tem;
}
+ trueop0 = avoid_constant_pool_reference (op0);
+ trueop1 = avoid_constant_pool_reference (op1);
+
if (VECTOR_MODE_P (mode)
&& GET_CODE (trueop0) == CONST_VECTOR
&& GET_CODE (trueop1) == CONST_VECTOR)
&& GET_CODE (trueop1) == CONST_DOUBLE
&& mode == GET_MODE (op0) && mode == GET_MODE (op1))
{
- REAL_VALUE_TYPE f0, f1, value;
+ if (code == AND
+ || code == IOR
+ || code == XOR)
+ {
+ long tmp0[4];
+ long tmp1[4];
+ REAL_VALUE_TYPE r;
+ int i;
+
+ real_to_target (tmp0, CONST_DOUBLE_REAL_VALUE (op0),
+ GET_MODE (op0));
+ real_to_target (tmp1, CONST_DOUBLE_REAL_VALUE (op1),
+ GET_MODE (op1));
+ for (i = 0; i < 4; i++)
+ {
+ if (code == AND)
+ tmp0[i] &= tmp1[i];
+ else if (code == IOR)
+ tmp0[i] |= tmp1[i];
+ else if (code == XOR)
+ tmp0[i] ^= tmp1[i];
+ else
+ abort ();
+ }
+ real_from_target (&r, tmp0, mode);
+ return CONST_DOUBLE_FROM_REAL_VALUE (r, mode);
+ }
+ else
+ {
+ REAL_VALUE_TYPE f0, f1, value;
- REAL_VALUE_FROM_CONST_DOUBLE (f0, trueop0);
- REAL_VALUE_FROM_CONST_DOUBLE (f1, trueop1);
- f0 = real_value_truncate (mode, f0);
- f1 = real_value_truncate (mode, f1);
+ REAL_VALUE_FROM_CONST_DOUBLE (f0, trueop0);
+ REAL_VALUE_FROM_CONST_DOUBLE (f1, trueop1);
+ f0 = real_value_truncate (mode, f0);
+ f1 = real_value_truncate (mode, f1);
- if (code == DIV
- && !MODE_HAS_INFINITIES (mode)
- && REAL_VALUES_EQUAL (f1, dconst0))
- return 0;
+ if (HONOR_SNANS (mode)
+ && (REAL_VALUE_ISNAN (f0) || REAL_VALUE_ISNAN (f1)))
+ return 0;
+
+ if (code == DIV
+ && REAL_VALUES_EQUAL (f1, dconst0)
+ && (flag_trapping_math || ! MODE_HAS_INFINITIES (mode)))
+ return 0;
- REAL_ARITHMETIC (value, rtx_to_tree_code (code), f0, f1);
+ REAL_ARITHMETIC (value, rtx_to_tree_code (code), f0, f1);
- value = real_value_truncate (mode, value);
- return CONST_DOUBLE_FROM_REAL_VALUE (value, mode);
+ value = real_value_truncate (mode, value);
+ return CONST_DOUBLE_FROM_REAL_VALUE (value, mode);
+ }
}
/* We can fold some multi-word operations. */
&& (GET_CODE (trueop1) == CONST_DOUBLE
|| GET_CODE (trueop1) == CONST_INT))
{
- unsigned HOST_WIDE_INT l1, l2, lv;
- HOST_WIDE_INT h1, h2, hv;
+ unsigned HOST_WIDE_INT l1, l2, lv, lt;
+ HOST_WIDE_INT h1, h2, hv, ht;
if (GET_CODE (trueop0) == CONST_DOUBLE)
l1 = CONST_DOUBLE_LOW (trueop0), h1 = CONST_DOUBLE_HIGH (trueop0);
neg_double (l2, h2, &lv, &hv);
l2 = lv, h2 = hv;
- /* .. fall through ... */
+ /* Fall through.... */
case PLUS:
add_double (l1, h1, l2, h2, &lv, &hv);
mul_double (l1, h1, l2, h2, &lv, &hv);
break;
- case DIV: case MOD: case UDIV: case UMOD:
- /* We'd need to include tree.h to do this and it doesn't seem worth
- it. */
- return 0;
+ case DIV:
+ if (div_and_round_double (TRUNC_DIV_EXPR, 0, l1, h1, l2, h2,
+ &lv, &hv, <, &ht))
+ return 0;
+ break;
+
+ case MOD:
+ if (div_and_round_double (TRUNC_DIV_EXPR, 0, l1, h1, l2, h2,
+ <, &ht, &lv, &hv))
+ return 0;
+ break;
+
+ case UDIV:
+ if (div_and_round_double (TRUNC_DIV_EXPR, 1, l1, h1, l2, h2,
+ &lv, &hv, <, &ht))
+ return 0;
+ break;
+
+ case UMOD:
+ if (div_and_round_double (TRUNC_DIV_EXPR, 1, l1, h1, l2, h2,
+ <, &ht, &lv, &hv))
+ return 0;
+ break;
case AND:
lv = l1 & l2, hv = h1 & h2;
case LSHIFTRT: case ASHIFTRT:
case ASHIFT:
case ROTATE: case ROTATERT:
-#ifdef SHIFT_COUNT_TRUNCATED
if (SHIFT_COUNT_TRUNCATED)
l2 &= (GET_MODE_BITSIZE (mode) - 1), h2 = 0;
-#endif
if (h2 != 0 || l2 >= GET_MODE_BITSIZE (mode))
return 0;
if (INTEGRAL_MODE_P (mode)
&& GET_CODE (op0) == NOT
&& trueop1 == const1_rtx)
- return gen_rtx_NEG (mode, XEXP (op0, 0));
+ return simplify_gen_unary (NEG, mode, XEXP (op0, 0), mode);
/* Handle both-operands-constant cases. We can only add
CONST_INTs to constants since the sum of relocatable symbols
}
}
+ /* (plus (xor X C1) C2) is (xor X (C1^C2)) if C2 is signbit. */
+ if ((GET_CODE (op1) == CONST_INT
+ || GET_CODE (op1) == CONST_DOUBLE)
+ && GET_CODE (op0) == XOR
+ && (GET_CODE (XEXP (op0, 1)) == CONST_INT
+ || GET_CODE (XEXP (op0, 1)) == CONST_DOUBLE)
+ && mode_signbit_p (mode, op1))
+ return simplify_gen_binary (XOR, mode, XEXP (op0, 0),
+ simplify_gen_binary (XOR, mode, op1,
+ XEXP (op0, 1)));
+
/* 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.
&& GET_CODE (XEXP (op1, 0)) == PLUS))
&& (tem = simplify_plus_minus (code, mode, op0, op1, 0)) != 0)
return tem;
+
+ /* Reassociate floating point addition only when the user
+ specifies unsafe math optimizations. */
+ if (FLOAT_MODE_P (mode)
+ && flag_unsafe_math_optimizations)
+ {
+ tem = simplify_associative_operation (code, mode, op0, op1);
+ if (tem)
+ return tem;
+ }
break;
case COMPARE:
But if the mode has signed zeros, and does not round towards
-infinity, then 0 - 0 is 0, not -0. */
if (!HONOR_SIGNED_ZEROS (mode) && trueop0 == CONST0_RTX (mode))
- return gen_rtx_NEG (mode, op1);
+ return simplify_gen_unary (NEG, mode, op1, mode);
/* (-1 - a) is ~a. */
if (trueop0 == constm1_rtx)
- return gen_rtx_NOT (mode, op1);
+ return simplify_gen_unary (NOT, mode, op1, mode);
/* Subtracting 0 has no effect unless the mode has signed zeros
and supports rounding towards -infinity. In such a case,
if (GET_CODE (op1) == NEG)
return simplify_gen_binary (PLUS, mode, op0, XEXP (op1, 0));
+ /* (-x - c) may be simplified as (-c - x). */
+ if (GET_CODE (op0) == NEG
+ && (GET_CODE (op1) == CONST_INT
+ || GET_CODE (op1) == CONST_DOUBLE))
+ {
+ tem = simplify_unary_operation (NEG, mode, op1, mode);
+ if (tem)
+ 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.
case MULT:
if (trueop1 == constm1_rtx)
- {
- tem = simplify_unary_operation (NEG, mode, op0, mode);
-
- return tem ? tem : gen_rtx_NEG (mode, op0);
- }
+ return simplify_gen_unary (NEG, mode, op0, mode);
/* Maybe simplify x * 0 to 0. The reduction is not valid if
x is NaN, since x * 0 is then also NaN. Nor is it valid
&& (width <= HOST_BITS_PER_WIDE_INT
|| val != HOST_BITS_PER_WIDE_INT - 1)
&& ! rtx_equal_function_value_matters)
- return gen_rtx_ASHIFT (mode, op0, GEN_INT (val));
+ return simplify_gen_binary (ASHIFT, mode, op0, GEN_INT (val));
/* x*2 is x+x and x*(-1) is -x */
if (GET_CODE (trueop1) == CONST_DOUBLE
REAL_VALUE_FROM_CONST_DOUBLE (d, trueop1);
if (REAL_VALUES_EQUAL (d, dconst2))
- return gen_rtx_PLUS (mode, op0, copy_rtx (op0));
+ return simplify_gen_binary (PLUS, mode, op0, copy_rtx (op0));
if (REAL_VALUES_EQUAL (d, dconstm1))
- return gen_rtx_NEG (mode, op0);
+ return simplify_gen_unary (NEG, mode, op0, mode);
+ }
+
+ /* Reassociate multiplication, but for floating point MULTs
+ only when the user specifies unsafe math optimizations. */
+ if (! FLOAT_MODE_P (mode)
+ || flag_unsafe_math_optimizations)
+ {
+ tem = simplify_associative_operation (code, mode, op0, op1);
+ if (tem)
+ return tem;
}
break;
&& ! side_effects_p (op0)
&& GET_MODE_CLASS (mode) != MODE_CC)
return constm1_rtx;
+ tem = simplify_associative_operation (code, mode, op0, op1);
+ if (tem)
+ return tem;
break;
case XOR:
if (GET_CODE (trueop1) == CONST_INT
&& ((INTVAL (trueop1) & GET_MODE_MASK (mode))
== GET_MODE_MASK (mode)))
- return gen_rtx_NOT (mode, op0);
- if (trueop0 == trueop1 && ! side_effects_p (op0)
+ return simplify_gen_unary (NOT, mode, op0, mode);
+ if (trueop0 == trueop1
+ && ! side_effects_p (op0)
&& GET_MODE_CLASS (mode) != MODE_CC)
return const0_rtx;
+
+ /* Canonicalize XOR of the most significant bit to PLUS. */
+ if ((GET_CODE (op1) == CONST_INT
+ || GET_CODE (op1) == CONST_DOUBLE)
+ && mode_signbit_p (mode, op1))
+ return simplify_gen_binary (PLUS, mode, op0, op1);
+ /* (xor (plus X C1) C2) is (xor X (C1^C2)) if C1 is signbit. */
+ if ((GET_CODE (op1) == CONST_INT
+ || GET_CODE (op1) == CONST_DOUBLE)
+ && GET_CODE (op0) == PLUS
+ && (GET_CODE (XEXP (op0, 1)) == CONST_INT
+ || GET_CODE (XEXP (op0, 1)) == CONST_DOUBLE)
+ && mode_signbit_p (mode, XEXP (op0, 1)))
+ return simplify_gen_binary (XOR, mode, XEXP (op0, 0),
+ simplify_gen_binary (XOR, mode, op1,
+ XEXP (op0, 1)));
+
+ tem = simplify_associative_operation (code, mode, op0, op1);
+ if (tem)
+ return tem;
break;
case AND:
&& ! side_effects_p (op0)
&& GET_MODE_CLASS (mode) != MODE_CC)
return const0_rtx;
+ tem = simplify_associative_operation (code, mode, op0, op1);
+ if (tem)
+ return tem;
break;
case UDIV:
- /* Convert divide by power of two into shift (divide by 1 handled
- below). */
- if (GET_CODE (trueop1) == CONST_INT
- && (arg1 = exact_log2 (INTVAL (trueop1))) > 0)
- return gen_rtx_LSHIFTRT (mode, op0, GEN_INT (arg1));
-
- /* ... fall through ... */
-
- case DIV:
- if (trueop1 == CONST1_RTX (mode))
+ /* 0/x is 0 (or x&0 if x has side-effects). */
+ if (trueop0 == const0_rtx)
+ return side_effects_p (op1)
+ ? simplify_gen_binary (AND, mode, op1, const0_rtx)
+ : const0_rtx;
+ /* x/1 is x. */
+ if (trueop1 == const1_rtx)
{
- /* On some platforms DIV uses narrower mode than its
- operands. */
+ /* Handle narrowing UDIV. */
rtx x = gen_lowpart_common (mode, op0);
if (x)
return x;
- else if (mode != GET_MODE (op0) && GET_MODE (op0) != VOIDmode)
+ if (mode != GET_MODE (op0) && GET_MODE (op0) != VOIDmode)
return gen_lowpart_SUBREG (mode, op0);
- else
- return op0;
+ return op0;
}
+ /* Convert divide by power of two into shift. */
+ if (GET_CODE (trueop1) == CONST_INT
+ && (arg1 = exact_log2 (INTVAL (trueop1))) > 0)
+ return simplify_gen_binary (LSHIFTRT, mode, op0, GEN_INT (arg1));
+ break;
- /* Maybe change 0 / x to 0. This transformation isn't safe for
- modes with NaNs, since 0 / 0 will then be NaN rather than 0.
- Nor is it safe for modes with signed zeros, since dividing
- 0 by a negative number gives -0, not 0. */
- if (!HONOR_NANS (mode)
- && !HONOR_SIGNED_ZEROS (mode)
- && trueop0 == CONST0_RTX (mode)
- && ! side_effects_p (op1))
- return op0;
-
- /* Change division by a constant into multiplication. Only do
- this with -funsafe-math-optimizations. */
- else if (GET_CODE (trueop1) == CONST_DOUBLE
- && GET_MODE_CLASS (GET_MODE (trueop1)) == MODE_FLOAT
- && trueop1 != CONST0_RTX (mode)
- && flag_unsafe_math_optimizations)
+ case DIV:
+ /* Handle floating point and integers separately. */
+ if (GET_MODE_CLASS (mode) == MODE_FLOAT)
{
- REAL_VALUE_TYPE d;
- REAL_VALUE_FROM_CONST_DOUBLE (d, trueop1);
+ /* Maybe change 0.0 / x to 0.0. This transformation isn't
+ safe for modes with NaNs, since 0.0 / 0.0 will then be
+ NaN rather than 0.0. Nor is it safe for modes with signed
+ zeros, since dividing 0 by a negative number gives -0.0 */
+ if (trueop0 == CONST0_RTX (mode)
+ && !HONOR_NANS (mode)
+ && !HONOR_SIGNED_ZEROS (mode)
+ && ! side_effects_p (op1))
+ return op0;
+ /* x/1.0 is x. */
+ if (trueop1 == CONST1_RTX (mode)
+ && !HONOR_SNANS (mode))
+ return op0;
- if (! REAL_VALUES_EQUAL (d, dconst0))
+ if (GET_CODE (trueop1) == CONST_DOUBLE
+ && trueop1 != CONST0_RTX (mode))
{
- REAL_ARITHMETIC (d, rtx_to_tree_code (DIV), dconst1, d);
- return gen_rtx_MULT (mode, op0,
- CONST_DOUBLE_FROM_REAL_VALUE (d, mode));
+ REAL_VALUE_TYPE d;
+ REAL_VALUE_FROM_CONST_DOUBLE (d, trueop1);
+
+ /* x/-1.0 is -x. */
+ if (REAL_VALUES_EQUAL (d, dconstm1)
+ && !HONOR_SNANS (mode))
+ return simplify_gen_unary (NEG, mode, op0, mode);
+
+ /* Change FP division by a constant into multiplication.
+ Only do this with -funsafe-math-optimizations. */
+ if (flag_unsafe_math_optimizations
+ && !REAL_VALUES_EQUAL (d, dconst0))
+ {
+ REAL_ARITHMETIC (d, RDIV_EXPR, dconst1, d);
+ tem = CONST_DOUBLE_FROM_REAL_VALUE (d, mode);
+ return simplify_gen_binary (MULT, mode, op0, tem);
+ }
+ }
+ }
+ else
+ {
+ /* 0/x is 0 (or x&0 if x has side-effects). */
+ if (trueop0 == const0_rtx)
+ return side_effects_p (op1)
+ ? simplify_gen_binary (AND, mode, op1, const0_rtx)
+ : const0_rtx;
+ /* x/1 is x. */
+ if (trueop1 == const1_rtx)
+ {
+ /* Handle narrowing DIV. */
+ rtx x = gen_lowpart_common (mode, op0);
+ if (x)
+ return x;
+ if (mode != GET_MODE (op0) && GET_MODE (op0) != VOIDmode)
+ return gen_lowpart_SUBREG (mode, op0);
+ return op0;
+ }
+ /* x/-1 is -x. */
+ if (trueop1 == constm1_rtx)
+ {
+ rtx x = gen_lowpart_common (mode, op0);
+ if (!x)
+ x = (mode != GET_MODE (op0) && GET_MODE (op0) != VOIDmode)
+ ? gen_lowpart_SUBREG (mode, op0) : op0;
+ return simplify_gen_unary (NEG, mode, x, mode);
}
}
break;
case UMOD:
- /* Handle modulus by power of two (mod with 1 handled below). */
+ /* 0%x is 0 (or x&0 if x has side-effects). */
+ if (trueop0 == const0_rtx)
+ return side_effects_p (op1)
+ ? simplify_gen_binary (AND, mode, op1, const0_rtx)
+ : const0_rtx;
+ /* x%1 is 0 (of x&0 if x has side-effects). */
+ if (trueop1 == const1_rtx)
+ return side_effects_p (op0)
+ ? simplify_gen_binary (AND, mode, op0, const0_rtx)
+ : const0_rtx;
+ /* Implement modulus by power of two as AND. */
if (GET_CODE (trueop1) == CONST_INT
&& exact_log2 (INTVAL (trueop1)) > 0)
- return gen_rtx_AND (mode, op0, GEN_INT (INTVAL (op1) - 1));
-
- /* ... fall through ... */
+ return simplify_gen_binary (AND, mode, op0,
+ GEN_INT (INTVAL (op1) - 1));
+ break;
case MOD:
- if ((trueop0 == const0_rtx || trueop1 == const1_rtx)
- && ! side_effects_p (op0) && ! side_effects_p (op1))
- return const0_rtx;
+ /* 0%x is 0 (or x&0 if x has side-effects). */
+ if (trueop0 == const0_rtx)
+ return side_effects_p (op1)
+ ? simplify_gen_binary (AND, mode, op1, const0_rtx)
+ : const0_rtx;
+ /* x%1 and x%-1 is 0 (or x&0 if x has side-effects). */
+ if (trueop1 == const1_rtx || trueop1 == constm1_rtx)
+ return side_effects_p (op0)
+ ? simplify_gen_binary (AND, mode, op0, const0_rtx)
+ : const0_rtx;
break;
case ROTATERT:
&& ! side_effects_p (op1))
return op0;
- /* ... fall through ... */
+ /* Fall through.... */
case ASHIFT:
case LSHIFTRT:
break;
case SMIN:
- if (width <= HOST_BITS_PER_WIDE_INT && GET_CODE (trueop1) == CONST_INT
+ if (width <= HOST_BITS_PER_WIDE_INT
+ && GET_CODE (trueop1) == CONST_INT
&& INTVAL (trueop1) == (HOST_WIDE_INT) 1 << (width -1)
&& ! side_effects_p (op0))
return op1;
- else if (rtx_equal_p (trueop0, trueop1) && ! side_effects_p (op0))
+ if (rtx_equal_p (trueop0, trueop1) && ! side_effects_p (op0))
return op0;
+ tem = simplify_associative_operation (code, mode, op0, op1);
+ if (tem)
+ return tem;
break;
case SMAX:
- if (width <= HOST_BITS_PER_WIDE_INT && GET_CODE (trueop1) == CONST_INT
+ if (width <= HOST_BITS_PER_WIDE_INT
+ && GET_CODE (trueop1) == CONST_INT
&& ((unsigned HOST_WIDE_INT) INTVAL (trueop1)
== (unsigned HOST_WIDE_INT) GET_MODE_MASK (mode) >> 1)
&& ! side_effects_p (op0))
return op1;
- else if (rtx_equal_p (trueop0, trueop1) && ! side_effects_p (op0))
+ if (rtx_equal_p (trueop0, trueop1) && ! side_effects_p (op0))
return op0;
+ tem = simplify_associative_operation (code, mode, op0, op1);
+ if (tem)
+ return tem;
break;
case UMIN:
if (trueop1 == const0_rtx && ! side_effects_p (op0))
return op1;
- else if (rtx_equal_p (trueop0, trueop1) && ! side_effects_p (op0))
+ if (rtx_equal_p (trueop0, trueop1) && ! side_effects_p (op0))
return op0;
+ tem = simplify_associative_operation (code, mode, op0, op1);
+ if (tem)
+ return tem;
break;
case UMAX:
if (trueop1 == constm1_rtx && ! side_effects_p (op0))
return op1;
- else if (rtx_equal_p (trueop0, trueop1) && ! side_effects_p (op0))
+ if (rtx_equal_p (trueop0, trueop1) && ! side_effects_p (op0))
return op0;
+ tem = simplify_associative_operation (code, mode, op0, op1);
+ if (tem)
+ return tem;
break;
case SS_PLUS:
if (arg1 < 0)
return 0;
-#ifdef SHIFT_COUNT_TRUNCATED
if (SHIFT_COUNT_TRUNCATED)
arg1 %= width;
-#endif
val = ((unsigned HOST_WIDE_INT) arg0) >> arg1;
break;
if (arg1 < 0)
return 0;
-#ifdef SHIFT_COUNT_TRUNCATED
if (SHIFT_COUNT_TRUNCATED)
arg1 %= width;
-#endif
val = ((unsigned HOST_WIDE_INT) arg0) << arg1;
break;
if (arg1 < 0)
return 0;
-#ifdef SHIFT_COUNT_TRUNCATED
if (SHIFT_COUNT_TRUNCATED)
arg1 %= width;
-#endif
val = arg0s >> arg1;
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, negate, changed;
+ int first, changed;
int i, j;
- memset ((char *) ops, 0, sizeof ops);
+ memset (ops, 0, sizeof ops);
/* Set up the two operands and then expand them until nothing has been
changed. If we run out of room in our array, give up; this should
/* Sort the operations based on swap_commutative_operands_p. */
qsort (ops, n_ops, sizeof (*ops), simplify_plus_minus_op_data_cmp);
+ /* Create (minus -C X) instead of (neg (const (plus X C))). */
+ if (n_ops == 2
+ && GET_CODE (ops[1].op) == CONST_INT
+ && CONSTANT_P (ops[0].op)
+ && ops[0].neg)
+ return gen_rtx_fmt_ee (MINUS, mode, ops[1].op, ops[0].op);
+
/* We suppressed creation of trivial CONST expressions in the
combination loop to avoid recursion. Create one manually now.
The combination loop should have ensured that there is exactly
|| (n_ops + n_consts == input_ops && n_consts <= input_consts)))
return NULL_RTX;
- /* Put a non-negated operand first. If there aren't any, make all
- operands positive and negate the whole thing later. */
+ /* Put a non-negated operand first, if possible. */
- negate = 0;
for (i = 0; i < n_ops && ops[i].neg; i++)
continue;
if (i == n_ops)
- {
- for (i = 0; i < n_ops; i++)
- ops[i].neg = 0;
- negate = 1;
- }
+ ops[0].op = gen_rtx_NEG (mode, ops[0].op);
else if (i != 0)
{
tem = ops[0].op;
result = gen_rtx_fmt_ee (ops[i].neg ? MINUS : PLUS,
mode, result, ops[i].op);
- return negate ? gen_rtx_NEG (mode, result) : result;
+ return result;
}
/* Like simplify_binary_operation except used for relational operators.
- MODE is the mode of the operands, not that of the result. If MODE
- is VOIDmode, both operands must also be VOIDmode and we compare the
- operands in "infinite precision".
-
- If no simplification is possible, this function returns zero. Otherwise,
- it returns either const_true_rtx or const0_rtx. */
+ MODE is the mode of the result. If MODE is VOIDmode, both operands must
+ also be VOIDmode.
+ CMP_MODE specifies in which mode the comparison is done in, so it is
+ the mode of the operands. If CMP_MODE is VOIDmode, it is taken from
+ the operands or, if both are VOIDmode, the operands are compared in
+ "infinite precision". */
rtx
simplify_relational_operation (enum rtx_code code, enum machine_mode mode,
- rtx op0, rtx op1)
+ enum machine_mode cmp_mode, rtx op0, rtx op1)
+{
+ rtx tem, trueop0, trueop1;
+
+ if (cmp_mode == VOIDmode)
+ cmp_mode = GET_MODE (op0);
+ if (cmp_mode == VOIDmode)
+ cmp_mode = GET_MODE (op1);
+
+ tem = simplify_const_relational_operation (code, cmp_mode, op0, op1);
+ if (tem)
+ {
+#ifdef FLOAT_STORE_FLAG_VALUE
+ if (GET_MODE_CLASS (mode) == MODE_FLOAT)
+ {
+ if (tem == const0_rtx)
+ return CONST0_RTX (mode);
+ else if (GET_MODE_CLASS (mode) == MODE_FLOAT)
+ {
+ REAL_VALUE_TYPE val;
+ val = FLOAT_STORE_FLAG_VALUE (mode);
+ return CONST_DOUBLE_FROM_REAL_VALUE (val, mode);
+ }
+ }
+#endif
+
+ return tem;
+ }
+
+ /* For the following tests, ensure const0_rtx is op1. */
+ if (swap_commutative_operands_p (op0, op1)
+ || (op0 == const0_rtx && op1 != const0_rtx))
+ tem = op0, op0 = op1, op1 = tem, code = swap_condition (code);
+
+ /* If op0 is a compare, extract the comparison arguments from it. */
+ if (GET_CODE (op0) == COMPARE && op1 == const0_rtx)
+ return simplify_relational_operation (code, mode, VOIDmode,
+ XEXP (op0, 0), XEXP (op0, 1));
+
+ if (mode == VOIDmode
+ || GET_MODE_CLASS (cmp_mode) == MODE_CC
+ || CC0_P (op0))
+ return NULL_RTX;
+
+ trueop0 = avoid_constant_pool_reference (op0);
+ trueop1 = avoid_constant_pool_reference (op1);
+ return simplify_relational_operation_1 (code, mode, cmp_mode,
+ trueop0, trueop1);
+}
+
+/* This part of simplify_relational_operation is only used when CMP_MODE
+ is not in class MODE_CC (i.e. it is a real comparison).
+
+ MODE is the mode of the result, while CMP_MODE specifies in which
+ mode the comparison is done in, so it is the mode of the operands. */
+rtx
+simplify_relational_operation_1 (enum rtx_code code, enum machine_mode mode,
+ enum machine_mode cmp_mode, rtx op0, rtx op1)
+{
+ if (GET_CODE (op1) == CONST_INT)
+ {
+ if (INTVAL (op1) == 0 && COMPARISON_P (op0))
+ {
+ /* If op0 is a comparison, extract the comparison arguments form it. */
+ if (code == NE)
+ {
+ if (GET_MODE (op0) == cmp_mode)
+ return simplify_rtx (op0);
+ else
+ return simplify_gen_relational (GET_CODE (op0), mode, VOIDmode,
+ XEXP (op0, 0), XEXP (op0, 1));
+ }
+ else if (code == EQ)
+ {
+ enum rtx_code new = reversed_comparison_code (op0, NULL_RTX);
+ if (new != UNKNOWN)
+ return simplify_gen_relational (new, mode, VOIDmode,
+ XEXP (op0, 0), XEXP (op0, 1));
+ }
+ }
+ }
+
+ return NULL_RTX;
+}
+
+/* Check if the given comparison (done in the given MODE) is actually a
+ tautology or a contradiction.
+ If no simplification is possible, this function returns zero.
+ Otherwise, it returns either const_true_rtx or const0_rtx. */
+
+rtx
+simplify_const_relational_operation (enum rtx_code code,
+ enum machine_mode mode,
+ rtx op0, rtx op1)
{
int equal, op0lt, op0ltu, op1lt, op1ltu;
rtx tem;
if (GET_CODE (op0) == COMPARE && op1 == const0_rtx)
op1 = XEXP (op0, 1), op0 = XEXP (op0, 0);
- trueop0 = avoid_constant_pool_reference (op0);
- trueop1 = avoid_constant_pool_reference (op1);
-
/* We can't simplify MODE_CC values since we don't know what the
actual comparison is. */
if (GET_MODE_CLASS (GET_MODE (op0)) == MODE_CC || CC0_P (op0))
return 0;
/* Make sure the constant is second. */
- if (swap_commutative_operands_p (trueop0, trueop1))
+ if (swap_commutative_operands_p (op0, op1))
{
tem = op0, op0 = op1, op1 = tem;
- tem = trueop0, trueop0 = trueop1, trueop1 = tem;
code = swap_condition (code);
}
+ trueop0 = avoid_constant_pool_reference (op0);
+ trueop1 = avoid_constant_pool_reference (op1);
+
/* For integer comparisons of A and B maybe we can simplify A - B and can
then simplify a comparison of that with zero. If A and B are both either
a register or a CONST_INT, this can't help; testing for these cases will
If CODE is an unsigned comparison, then we can never do this optimization,
because it gives an incorrect result if the subtraction wraps around zero.
ANSI C defines unsigned operations such that they never overflow, and
- thus such cases can not be ignored. */
+ thus such cases can not be ignored; but we cannot do it even for
+ signed comparisons for languages such as Java, so test flag_wrapv. */
- if (INTEGRAL_MODE_P (mode) && trueop1 != const0_rtx
+ if (!flag_wrapv && INTEGRAL_MODE_P (mode) && trueop1 != const0_rtx
&& ! ((GET_CODE (op0) == REG || GET_CODE (trueop0) == CONST_INT)
&& (GET_CODE (op1) == REG || GET_CODE (trueop1) == CONST_INT))
&& 0 != (tem = simplify_binary_operation (MINUS, mode, op0, op1))
+ /* We cannot do this for == or != if tem is a nonzero address. */
+ && ((code != EQ && code != NE) || ! nonzero_address_p (tem))
&& code != GTU && code != GEU && code != LTU && code != LEU)
- return simplify_relational_operation (signed_condition (code),
- mode, tem, const0_rtx);
+ return simplify_const_relational_operation (signed_condition (code),
+ mode, tem, const0_rtx);
if (flag_unsafe_math_optimizations && code == ORDERED)
return const_true_rtx;
if (GET_CODE (op0) == CONST_INT)
return op0 != const0_rtx ? op1 : op2;
- /* Convert a == b ? b : a to "a". */
- if (GET_CODE (op0) == NE && ! side_effects_p (op0)
- && !HONOR_NANS (mode)
- && rtx_equal_p (XEXP (op0, 0), op1)
- && rtx_equal_p (XEXP (op0, 1), op2))
+ /* Convert c ? a : a into "a". */
+ if (rtx_equal_p (op1, op2) && ! side_effects_p (op0))
+ return op1;
+
+ /* Convert a != b ? a : b into "a". */
+ if (GET_CODE (op0) == NE
+ && ! side_effects_p (op0)
+ && ! HONOR_NANS (mode)
+ && ! HONOR_SIGNED_ZEROS (mode)
+ && ((rtx_equal_p (XEXP (op0, 0), op1)
+ && rtx_equal_p (XEXP (op0, 1), op2))
+ || (rtx_equal_p (XEXP (op0, 0), op2)
+ && rtx_equal_p (XEXP (op0, 1), op1))))
return op1;
- else if (GET_CODE (op0) == EQ && ! side_effects_p (op0)
- && !HONOR_NANS (mode)
- && rtx_equal_p (XEXP (op0, 1), op1)
- && rtx_equal_p (XEXP (op0, 0), op2))
+
+ /* Convert a == b ? a : b into "b". */
+ if (GET_CODE (op0) == EQ
+ && ! side_effects_p (op0)
+ && ! HONOR_NANS (mode)
+ && ! HONOR_SIGNED_ZEROS (mode)
+ && ((rtx_equal_p (XEXP (op0, 0), op1)
+ && rtx_equal_p (XEXP (op0, 1), op2))
+ || (rtx_equal_p (XEXP (op0, 0), op2)
+ && rtx_equal_p (XEXP (op0, 1), op1))))
return op2;
- else if (GET_RTX_CLASS (GET_CODE (op0)) == '<' && ! side_effects_p (op0))
+
+ if (COMPARISON_P (op0) && ! side_effects_p (op0))
{
enum machine_mode cmp_mode = (GET_MODE (XEXP (op0, 0)) == VOIDmode
? GET_MODE (XEXP (op0, 1))
: GET_MODE (XEXP (op0, 0)));
rtx temp;
- if (cmp_mode == VOIDmode)
- cmp_mode = op0_mode;
- temp = simplify_relational_operation (GET_CODE (op0), cmp_mode,
- XEXP (op0, 0), XEXP (op0, 1));
-
- /* See if any simplifications were possible. */
- if (temp == const0_rtx)
- return op2;
- else if (temp == const1_rtx)
- return op1;
- else if (temp)
- op0 = temp;
/* Look for happy constants in op1 and op2. */
if (GET_CODE (op1) == CONST_INT && GET_CODE (op2) == CONST_INT)
else
break;
- return gen_rtx_fmt_ee (code, mode, XEXP (op0, 0), XEXP (op0, 1));
+ return simplify_gen_relational (code, mode, cmp_mode,
+ XEXP (op0, 0), XEXP (op0, 1));
+ }
+
+ if (cmp_mode == VOIDmode)
+ cmp_mode = op0_mode;
+ temp = simplify_relational_operation (GET_CODE (op0), op0_mode,
+ cmp_mode, XEXP (op0, 0),
+ XEXP (op0, 1));
+
+ /* See if any simplifications were possible. */
+ if (temp)
+ {
+ if (GET_CODE (temp) == CONST_INT)
+ return temp == const0_rtx ? op2 : op1;
+ else if (temp)
+ return gen_rtx_IF_THEN_ELSE (mode, temp, op1, op2);
}
}
break;
+
case VEC_MERGE:
if (GET_MODE (op0) != mode
|| GET_MODE (op1) != mode
return 0;
}
-/* Simplify SUBREG:OUTERMODE(OP:INNERMODE, BYTE)
- Return 0 if no simplifications is possible. */
-rtx
-simplify_subreg (enum machine_mode outermode, rtx op,
- enum machine_mode innermode, unsigned int byte)
-{
- /* Little bit of sanity checking. */
- if (innermode == VOIDmode || outermode == VOIDmode
- || innermode == BLKmode || outermode == BLKmode)
- abort ();
+/* Evaluate a SUBREG of a CONST_INT or CONST_DOUBLE or CONST_VECTOR,
+ returning another CONST_INT or CONST_DOUBLE or CONST_VECTOR.
- if (GET_MODE (op) != innermode
- && GET_MODE (op) != VOIDmode)
- abort ();
+ Works by unpacking OP into a collection of 8-bit values
+ represented as a little-endian array of 'unsigned char', selecting by BYTE,
+ and then repacking them again for OUTERMODE. */
- if (byte % GET_MODE_SIZE (outermode)
- || byte >= GET_MODE_SIZE (innermode))
- abort ();
-
- if (outermode == innermode && !byte)
+static rtx
+simplify_immed_subreg (enum machine_mode outermode, rtx op,
+ enum machine_mode innermode, unsigned int byte)
+{
+ /* We support up to 512-bit values (for V8DFmode). */
+ enum {
+ max_bitsize = 512,
+ value_bit = 8,
+ value_mask = (1 << value_bit) - 1
+ };
+ unsigned char value[max_bitsize / value_bit];
+ int value_start;
+ int i;
+ int elem;
+
+ int num_elem;
+ rtx * elems;
+ int elem_bitsize;
+ rtx result_s;
+ rtvec result_v = NULL;
+ enum mode_class outer_class;
+ enum machine_mode outer_submode;
+
+ /* Some ports misuse CCmode. */
+ if (GET_MODE_CLASS (outermode) == MODE_CC && GET_CODE (op) == CONST_INT)
return op;
- /* Simplify subregs of vector constants. */
+ /* Unpack the value. */
+
if (GET_CODE (op) == CONST_VECTOR)
{
- int elt_size = GET_MODE_SIZE (GET_MODE_INNER (innermode));
- const unsigned int offset = byte / elt_size;
- rtx elt;
+ num_elem = CONST_VECTOR_NUNITS (op);
+ elems = &CONST_VECTOR_ELT (op, 0);
+ elem_bitsize = GET_MODE_BITSIZE (GET_MODE_INNER (innermode));
+ }
+ else
+ {
+ num_elem = 1;
+ elems = &op;
+ elem_bitsize = max_bitsize;
+ }
- if (GET_MODE_INNER (innermode) == outermode)
+ if (BITS_PER_UNIT % value_bit != 0)
+ abort (); /* Too complicated; reducing value_bit may help. */
+ if (elem_bitsize % BITS_PER_UNIT != 0)
+ abort (); /* I don't know how to handle endianness of sub-units. */
+
+ for (elem = 0; elem < num_elem; elem++)
+ {
+ unsigned char * vp;
+ rtx el = elems[elem];
+
+ /* Vectors are kept in target memory order. (This is probably
+ a mistake.) */
+ {
+ unsigned byte = (elem * elem_bitsize) / BITS_PER_UNIT;
+ unsigned ibyte = (((num_elem - 1 - elem) * elem_bitsize)
+ / BITS_PER_UNIT);
+ unsigned word_byte = WORDS_BIG_ENDIAN ? ibyte : byte;
+ unsigned subword_byte = BYTES_BIG_ENDIAN ? ibyte : byte;
+ unsigned bytele = (subword_byte % UNITS_PER_WORD
+ + (word_byte / UNITS_PER_WORD) * UNITS_PER_WORD);
+ vp = value + (bytele * BITS_PER_UNIT) / value_bit;
+ }
+
+ switch (GET_CODE (el))
{
- elt = CONST_VECTOR_ELT (op, offset);
-
- /* ?? We probably don't need this copy_rtx because constants
- can be shared. ?? */
+ case CONST_INT:
+ for (i = 0;
+ i < HOST_BITS_PER_WIDE_INT && i < elem_bitsize;
+ i += value_bit)
+ *vp++ = INTVAL (el) >> i;
+ /* CONST_INTs are always logically sign-extended. */
+ for (; i < elem_bitsize; i += value_bit)
+ *vp++ = INTVAL (el) < 0 ? -1 : 0;
+ break;
+
+ case CONST_DOUBLE:
+ if (GET_MODE (el) == VOIDmode)
+ {
+ /* If this triggers, someone should have generated a
+ CONST_INT instead. */
+ if (elem_bitsize <= HOST_BITS_PER_WIDE_INT)
+ abort ();
- return copy_rtx (elt);
- }
- else if (GET_MODE_INNER (innermode) == GET_MODE_INNER (outermode)
- && GET_MODE_SIZE (innermode) > GET_MODE_SIZE (outermode))
- {
- return (gen_rtx_CONST_VECTOR
- (outermode,
- gen_rtvec_v (GET_MODE_NUNITS (outermode),
- &CONST_VECTOR_ELT (op, offset))));
- }
- else if (GET_MODE_CLASS (outermode) == MODE_INT
- && (GET_MODE_SIZE (outermode) % elt_size == 0))
- {
- /* This happens when the target register size is smaller then
- the vector mode, and we synthesize operations with vectors
- of elements that are smaller than the register size. */
- HOST_WIDE_INT sum = 0, high = 0;
- unsigned n_elts = (GET_MODE_SIZE (outermode) / elt_size);
- unsigned i = BYTES_BIG_ENDIAN ? offset : offset + n_elts - 1;
- unsigned step = BYTES_BIG_ENDIAN ? 1 : -1;
- int shift = BITS_PER_UNIT * elt_size;
- unsigned HOST_WIDE_INT unit_mask;
-
- unit_mask = (unsigned HOST_WIDE_INT) -1
- >> (sizeof (HOST_WIDE_INT) * BITS_PER_UNIT - shift);
-
- for (; n_elts--; i += step)
+ for (i = 0; i < HOST_BITS_PER_WIDE_INT; i += value_bit)
+ *vp++ = CONST_DOUBLE_LOW (el) >> i;
+ while (i < HOST_BITS_PER_WIDE_INT * 2 && i < elem_bitsize)
+ {
+ *vp++
+ = CONST_DOUBLE_HIGH (el) >> (i - HOST_BITS_PER_WIDE_INT);
+ i += value_bit;
+ }
+ /* It shouldn't matter what's done here, so fill it with
+ zero. */
+ for (; i < max_bitsize; i += value_bit)
+ *vp++ = 0;
+ }
+ else if (GET_MODE_CLASS (GET_MODE (el)) == MODE_FLOAT)
{
- elt = CONST_VECTOR_ELT (op, i);
- if (GET_CODE (elt) == CONST_DOUBLE
- && GET_MODE_CLASS (GET_MODE (elt)) == MODE_FLOAT)
+ long tmp[max_bitsize / 32];
+ int bitsize = GET_MODE_BITSIZE (GET_MODE (el));
+
+ if (bitsize > elem_bitsize)
+ abort ();
+ if (bitsize % value_bit != 0)
+ abort ();
+
+ real_to_target (tmp, CONST_DOUBLE_REAL_VALUE (el),
+ GET_MODE (el));
+
+ /* real_to_target produces its result in words affected by
+ FLOAT_WORDS_BIG_ENDIAN. However, we ignore this,
+ and use WORDS_BIG_ENDIAN instead; see the documentation
+ of SUBREG in rtl.texi. */
+ for (i = 0; i < bitsize; i += value_bit)
{
- elt = gen_lowpart_common (int_mode_for_mode (GET_MODE (elt)),
- elt);
- if (! elt)
- return NULL_RTX;
+ int ibase;
+ if (WORDS_BIG_ENDIAN)
+ ibase = bitsize - 1 - i;
+ else
+ ibase = i;
+ *vp++ = tmp[ibase / 32] >> i % 32;
}
- if (GET_CODE (elt) != CONST_INT)
- return NULL_RTX;
- /* Avoid overflow. */
- if (high >> (HOST_BITS_PER_WIDE_INT - shift))
- return NULL_RTX;
- high = high << shift | sum >> (HOST_BITS_PER_WIDE_INT - shift);
- sum = (sum << shift) + (INTVAL (elt) & unit_mask);
+
+ /* It shouldn't matter what's done here, so fill it with
+ zero. */
+ for (; i < elem_bitsize; i += value_bit)
+ *vp++ = 0;
}
- if (GET_MODE_BITSIZE (outermode) <= HOST_BITS_PER_WIDE_INT)
- return GEN_INT (trunc_int_for_mode (sum, outermode));
- else if (GET_MODE_BITSIZE (outermode) == 2* HOST_BITS_PER_WIDE_INT)
- return immed_double_const (sum, high, outermode);
else
- return NULL_RTX;
- }
- else if (GET_MODE_CLASS (outermode) == MODE_INT
- && (elt_size % GET_MODE_SIZE (outermode) == 0))
- {
- enum machine_mode new_mode
- = int_mode_for_mode (GET_MODE_INNER (innermode));
- int subbyte = byte % elt_size;
-
- op = simplify_subreg (new_mode, op, innermode, byte - subbyte);
- if (! op)
- return NULL_RTX;
- return simplify_subreg (outermode, op, new_mode, subbyte);
+ abort ();
+ break;
+
+ default:
+ abort ();
}
- else if (GET_MODE_CLASS (outermode) == MODE_INT)
- /* This shouldn't happen, but let's not do anything stupid. */
- return NULL_RTX;
}
- /* Attempt to simplify constant to non-SUBREG expression. */
- if (CONSTANT_P (op))
+ /* Now, pick the right byte to start with. */
+ /* Renumber BYTE so that the least-significant byte is byte 0. A special
+ case is paradoxical SUBREGs, which shouldn't be adjusted since they
+ will already have offset 0. */
+ if (GET_MODE_SIZE (innermode) >= GET_MODE_SIZE (outermode))
{
- int offset, part;
- unsigned HOST_WIDE_INT val = 0;
+ unsigned ibyte = (GET_MODE_SIZE (innermode) - GET_MODE_SIZE (outermode)
+ - byte);
+ unsigned word_byte = WORDS_BIG_ENDIAN ? ibyte : byte;
+ unsigned subword_byte = BYTES_BIG_ENDIAN ? ibyte : byte;
+ byte = (subword_byte % UNITS_PER_WORD
+ + (word_byte / UNITS_PER_WORD) * UNITS_PER_WORD);
+ }
- if (VECTOR_MODE_P (outermode))
- {
- /* Construct a CONST_VECTOR from individual subregs. */
- enum machine_mode submode = GET_MODE_INNER (outermode);
- int subsize = GET_MODE_UNIT_SIZE (outermode);
- int i, elts = GET_MODE_NUNITS (outermode);
- rtvec v = rtvec_alloc (elts);
- rtx elt;
-
- for (i = 0; i < elts; i++, byte += subsize)
- {
- /* This might fail, e.g. if taking a subreg from a SYMBOL_REF. */
- /* ??? It would be nice if we could actually make such subregs
- on targets that allow such relocations. */
- if (byte >= GET_MODE_SIZE (innermode))
- elt = CONST0_RTX (submode);
- else
- elt = simplify_subreg (submode, op, innermode, byte);
- if (! elt)
- return NULL_RTX;
- RTVEC_ELT (v, i) = elt;
- }
- return gen_rtx_CONST_VECTOR (outermode, v);
- }
+ /* BYTE should still be inside OP. (Note that BYTE is unsigned,
+ so if it's become negative it will instead be very large.) */
+ if (byte >= GET_MODE_SIZE (innermode))
+ abort ();
- /* ??? This code is partly redundant with code below, but can handle
- the subregs of floats and similar corner cases.
- Later it we should move all simplification code here and rewrite
- GEN_LOWPART_IF_POSSIBLE, GEN_HIGHPART, OPERAND_SUBWORD and friends
- using SIMPLIFY_SUBREG. */
- if (subreg_lowpart_offset (outermode, innermode) == byte
- && GET_CODE (op) != CONST_VECTOR)
- {
- rtx new = gen_lowpart_if_possible (outermode, op);
- if (new)
- return new;
- }
+ /* Convert from bytes to chunks of size value_bit. */
+ value_start = byte * (BITS_PER_UNIT / value_bit);
- /* Similar comment as above apply here. */
- if (GET_MODE_SIZE (outermode) == UNITS_PER_WORD
- && GET_MODE_SIZE (innermode) > UNITS_PER_WORD
- && GET_MODE_CLASS (outermode) == MODE_INT)
- {
- rtx new = constant_subword (op,
- (byte / UNITS_PER_WORD),
- innermode);
- if (new)
- return new;
- }
+ /* Re-pack the value. */
+
+ if (VECTOR_MODE_P (outermode))
+ {
+ num_elem = GET_MODE_NUNITS (outermode);
+ result_v = rtvec_alloc (num_elem);
+ elems = &RTVEC_ELT (result_v, 0);
+ outer_submode = GET_MODE_INNER (outermode);
+ }
+ else
+ {
+ num_elem = 1;
+ elems = &result_s;
+ outer_submode = outermode;
+ }
- if (GET_MODE_CLASS (outermode) != MODE_INT
- && GET_MODE_CLASS (outermode) != MODE_CC)
- {
- enum machine_mode new_mode = int_mode_for_mode (outermode);
+ outer_class = GET_MODE_CLASS (outer_submode);
+ elem_bitsize = GET_MODE_BITSIZE (outer_submode);
- if (new_mode != innermode || byte != 0)
- {
- op = simplify_subreg (new_mode, op, innermode, byte);
- if (! op)
- return NULL_RTX;
- return simplify_subreg (outermode, op, new_mode, 0);
- }
- }
+ if (elem_bitsize % value_bit != 0)
+ abort ();
+ if (elem_bitsize + value_start * value_bit > max_bitsize)
+ abort ();
- offset = byte * BITS_PER_UNIT;
- switch (GET_CODE (op))
- {
- case CONST_DOUBLE:
- if (GET_MODE (op) != VOIDmode)
- break;
+ for (elem = 0; elem < num_elem; elem++)
+ {
+ unsigned char *vp;
+
+ /* Vectors are stored in target memory order. (This is probably
+ a mistake.) */
+ {
+ unsigned byte = (elem * elem_bitsize) / BITS_PER_UNIT;
+ unsigned ibyte = (((num_elem - 1 - elem) * elem_bitsize)
+ / BITS_PER_UNIT);
+ unsigned word_byte = WORDS_BIG_ENDIAN ? ibyte : byte;
+ unsigned subword_byte = BYTES_BIG_ENDIAN ? ibyte : byte;
+ unsigned bytele = (subword_byte % UNITS_PER_WORD
+ + (word_byte / UNITS_PER_WORD) * UNITS_PER_WORD);
+ vp = value + value_start + (bytele * BITS_PER_UNIT) / value_bit;
+ }
- /* We can't handle this case yet. */
- if (GET_MODE_BITSIZE (outermode) >= HOST_BITS_PER_WIDE_INT)
- return NULL_RTX;
+ switch (outer_class)
+ {
+ case MODE_INT:
+ case MODE_PARTIAL_INT:
+ {
+ unsigned HOST_WIDE_INT hi = 0, lo = 0;
+
+ for (i = 0;
+ i < HOST_BITS_PER_WIDE_INT && i < elem_bitsize;
+ i += value_bit)
+ lo |= (HOST_WIDE_INT)(*vp++ & value_mask) << i;
+ for (; i < elem_bitsize; i += value_bit)
+ hi |= ((HOST_WIDE_INT)(*vp++ & value_mask)
+ << (i - HOST_BITS_PER_WIDE_INT));
+
+ /* immed_double_const doesn't call trunc_int_for_mode. I don't
+ know why. */
+ if (elem_bitsize <= HOST_BITS_PER_WIDE_INT)
+ elems[elem] = gen_int_mode (lo, outer_submode);
+ else
+ elems[elem] = immed_double_const (lo, hi, outer_submode);
+ }
+ break;
+
+ case MODE_FLOAT:
+ {
+ REAL_VALUE_TYPE r;
+ long tmp[max_bitsize / 32];
+
+ /* real_from_target wants its input in words affected by
+ FLOAT_WORDS_BIG_ENDIAN. However, we ignore this,
+ and use WORDS_BIG_ENDIAN instead; see the documentation
+ of SUBREG in rtl.texi. */
+ for (i = 0; i < max_bitsize / 32; i++)
+ tmp[i] = 0;
+ for (i = 0; i < elem_bitsize; i += value_bit)
+ {
+ int ibase;
+ if (WORDS_BIG_ENDIAN)
+ ibase = elem_bitsize - 1 - i;
+ else
+ ibase = i;
+ tmp[ibase / 32] |= (*vp++ & value_mask) << i % 32;
+ }
- part = offset >= HOST_BITS_PER_WIDE_INT;
- if ((BITS_PER_WORD > HOST_BITS_PER_WIDE_INT
- && BYTES_BIG_ENDIAN)
- || (BITS_PER_WORD <= HOST_BITS_PER_WIDE_INT
- && WORDS_BIG_ENDIAN))
- part = !part;
- val = part ? CONST_DOUBLE_HIGH (op) : CONST_DOUBLE_LOW (op);
- offset %= HOST_BITS_PER_WIDE_INT;
+ real_from_target (&r, tmp, outer_submode);
+ elems[elem] = CONST_DOUBLE_FROM_REAL_VALUE (r, outer_submode);
+ }
+ break;
+
+ default:
+ abort ();
+ }
+ }
+ if (VECTOR_MODE_P (outermode))
+ return gen_rtx_CONST_VECTOR (outermode, result_v);
+ else
+ return result_s;
+}
- /* We've already picked the word we want from a double, so
- pretend this is actually an integer. */
- innermode = mode_for_size (HOST_BITS_PER_WIDE_INT, MODE_INT, 0);
+/* Simplify SUBREG:OUTERMODE(OP:INNERMODE, BYTE)
+ Return 0 if no simplifications are possible. */
+rtx
+simplify_subreg (enum machine_mode outermode, rtx op,
+ enum machine_mode innermode, unsigned int byte)
+{
+ /* Little bit of sanity checking. */
+ if (innermode == VOIDmode || outermode == VOIDmode
+ || innermode == BLKmode || outermode == BLKmode)
+ abort ();
- /* FALLTHROUGH */
- case CONST_INT:
- if (GET_CODE (op) == CONST_INT)
- val = INTVAL (op);
+ if (GET_MODE (op) != innermode
+ && GET_MODE (op) != VOIDmode)
+ abort ();
- /* We don't handle synthesizing of non-integral constants yet. */
- if (GET_MODE_CLASS (outermode) != MODE_INT)
- return NULL_RTX;
+ if (byte % GET_MODE_SIZE (outermode)
+ || byte >= GET_MODE_SIZE (innermode))
+ abort ();
- if (BYTES_BIG_ENDIAN || WORDS_BIG_ENDIAN)
- {
- if (WORDS_BIG_ENDIAN)
- offset = (GET_MODE_BITSIZE (innermode)
- - GET_MODE_BITSIZE (outermode) - offset);
- if (BYTES_BIG_ENDIAN != WORDS_BIG_ENDIAN
- && GET_MODE_SIZE (outermode) < UNITS_PER_WORD)
- offset = (offset + BITS_PER_WORD - GET_MODE_BITSIZE (outermode)
- - 2 * (offset % BITS_PER_WORD));
- }
+ if (outermode == innermode && !byte)
+ return op;
- if (offset >= HOST_BITS_PER_WIDE_INT)
- return ((HOST_WIDE_INT) val < 0) ? constm1_rtx : const0_rtx;
- else
- {
- val >>= offset;
- if (GET_MODE_BITSIZE (outermode) < HOST_BITS_PER_WIDE_INT)
- val = trunc_int_for_mode (val, outermode);
- return GEN_INT (val);
- }
- default:
- break;
- }
- }
+ if (GET_CODE (op) == CONST_INT
+ || GET_CODE (op) == CONST_DOUBLE
+ || GET_CODE (op) == CONST_VECTOR)
+ return simplify_immed_subreg (outermode, op, innermode, byte);
/* Changing mode twice with SUBREG => just change it once,
or not at all if changing back op starting mode. */
#if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
&& REGNO (op) != ARG_POINTER_REGNUM
#endif
- && REGNO (op) != STACK_POINTER_REGNUM)
+ && REGNO (op) != STACK_POINTER_REGNUM
+ && subreg_offset_representable_p (REGNO (op), innermode,
+ byte, outermode))
{
- int final_regno = subreg_hard_regno (gen_rtx_SUBREG (outermode, op, byte),
- 0);
+ rtx tem = gen_rtx_SUBREG (outermode, op, byte);
+ int final_regno = subreg_hard_regno (tem, 0);
/* ??? We do allow it if the current REG is not valid for
its mode. This is a kludge to work around how float/complex
of real and imaginary part. */
if (GET_CODE (op) == CONCAT)
{
- int is_realpart = byte < GET_MODE_UNIT_SIZE (innermode);
+ int is_realpart = byte < (unsigned int) GET_MODE_UNIT_SIZE (innermode);
rtx part = is_realpart ? XEXP (op, 0) : XEXP (op, 1);
unsigned int final_offset;
rtx res;
res = simplify_subreg (outermode, part, GET_MODE (part), final_offset);
if (res)
return res;
- /* We can at least simplify it by referring directly to the relevant part. */
+ /* We can at least simplify it by referring directly to the
+ relevant part. */
return gen_rtx_SUBREG (outermode, part, final_offset);
}
+ /* Optimize SUBREG truncations of zero and sign extended values. */
+ if ((GET_CODE (op) == ZERO_EXTEND
+ || GET_CODE (op) == SIGN_EXTEND)
+ && GET_MODE_BITSIZE (outermode) < GET_MODE_BITSIZE (innermode))
+ {
+ unsigned int bitpos = subreg_lsb_1 (outermode, innermode, byte);
+
+ /* If we're requesting the lowpart of a zero or sign extension,
+ there are three possibilities. If the outermode is the same
+ as the origmode, we can omit both the extension and the subreg.
+ If the outermode is not larger than the origmode, we can apply
+ the truncation without the extension. Finally, if the outermode
+ is larger than the origmode, but both are integer modes, we
+ can just extend to the appropriate mode. */
+ if (bitpos == 0)
+ {
+ enum machine_mode origmode = GET_MODE (XEXP (op, 0));
+ if (outermode == origmode)
+ return XEXP (op, 0);
+ if (GET_MODE_BITSIZE (outermode) <= GET_MODE_BITSIZE (origmode))
+ return simplify_gen_subreg (outermode, XEXP (op, 0), origmode,
+ subreg_lowpart_offset (outermode,
+ origmode));
+ if (SCALAR_INT_MODE_P (outermode))
+ return simplify_gen_unary (GET_CODE (op), outermode,
+ XEXP (op, 0), origmode);
+ }
+
+ /* A SUBREG resulting from a zero extension may fold to zero if
+ it extracts higher bits that the ZERO_EXTEND's source bits. */
+ if (GET_CODE (op) == ZERO_EXTEND
+ && bitpos >= GET_MODE_BITSIZE (GET_MODE (XEXP (op, 0))))
+ return CONST0_RTX (outermode);
+ }
+
return NULL_RTX;
}
+
/* Make a SUBREG operation or equivalent if it folds. */
rtx
switch (GET_RTX_CLASS (code))
{
- case '1':
+ case RTX_UNARY:
return simplify_unary_operation (code, mode,
XEXP (x, 0), GET_MODE (XEXP (x, 0)));
- case 'c':
+ case RTX_COMM_ARITH:
if (swap_commutative_operands_p (XEXP (x, 0), XEXP (x, 1)))
- {
- rtx tem;
+ return simplify_gen_binary (code, mode, XEXP (x, 1), XEXP (x, 0));
- tem = XEXP (x, 0);
- XEXP (x, 0) = XEXP (x, 1);
- XEXP (x, 1) = tem;
- return simplify_binary_operation (code, mode,
- XEXP (x, 0), XEXP (x, 1));
- }
+ /* Fall through.... */
- case '2':
+ case RTX_BIN_ARITH:
return simplify_binary_operation (code, mode, XEXP (x, 0), XEXP (x, 1));
- case '3':
- case 'b':
+ case RTX_TERNARY:
+ case RTX_BITFIELD_OPS:
return simplify_ternary_operation (code, mode, GET_MODE (XEXP (x, 0)),
XEXP (x, 0), XEXP (x, 1),
XEXP (x, 2));
- case '<':
- return simplify_relational_operation (code,
- ((GET_MODE (XEXP (x, 0))
- != VOIDmode)
- ? GET_MODE (XEXP (x, 0))
- : GET_MODE (XEXP (x, 1))),
- XEXP (x, 0), XEXP (x, 1));
- case 'x':
+ case RTX_COMPARE:
+ case RTX_COMM_COMPARE:
+ return simplify_relational_operation (code, mode,
+ ((GET_MODE (XEXP (x, 0))
+ != VOIDmode)
+ ? GET_MODE (XEXP (x, 0))
+ : GET_MODE (XEXP (x, 1))),
+ XEXP (x, 0),
+ XEXP (x, 1));
+
+ case RTX_EXTRA:
if (code == SUBREG)
return simplify_gen_subreg (mode, SUBREG_REG (x),
GET_MODE (SUBREG_REG (x)),
if (CONSTANT_P (XEXP (x, 0)))
return const1_rtx;
}
- return NULL;
+ break;
+
+ case RTX_OBJ:
+ if (code == LO_SUM)
+ {
+ /* Convert (lo_sum (high FOO) FOO) to FOO. */
+ if (GET_CODE (XEXP (x, 0)) == HIGH
+ && rtx_equal_p (XEXP (XEXP (x, 0), 0), XEXP (x, 1)))
+ return XEXP (x, 1);
+ }
+ break;
+
default:
- return NULL;
+ break;
}
+ return NULL;
}
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