/* RTL simplification functions for GNU compiler.
Copyright (C) 1987, 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
- 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc.
+ 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007
+ Free Software Foundation, Inc.
This file is part of GCC.
return x;
}
+ if (GET_MODE (x) == BLKmode)
+ return x;
+
addr = XEXP (x, 0);
/* Call target hook to avoid the effects of -fpic etc.... */
return x;
}
-
-/* Return true if X is a MEM referencing the constant pool. */
-
-bool
-constant_pool_reference_p (rtx x)
-{
- return avoid_constant_pool_reference (x) != x;
-}
\f
/* Make a unary operation by first seeing if it folds and otherwise making
the specified operation. */
/* (float_truncate (float x)) is (float x) */
if (GET_CODE (op) == FLOAT
&& (flag_unsafe_math_optimizations
- || ((unsigned)significand_size (GET_MODE (op))
- >= (GET_MODE_BITSIZE (GET_MODE (XEXP (op, 0)))
- - num_sign_bit_copies (XEXP (op, 0),
- GET_MODE (XEXP (op, 0)))))))
+ || (SCALAR_FLOAT_MODE_P (GET_MODE (op))
+ && ((unsigned)significand_size (GET_MODE (op))
+ >= (GET_MODE_BITSIZE (GET_MODE (XEXP (op, 0)))
+ - num_sign_bit_copies (XEXP (op, 0),
+ GET_MODE (XEXP (op, 0))))))))
return simplify_gen_unary (FLOAT, mode,
XEXP (op, 0),
GET_MODE (XEXP (op, 0)));
*/
if (GET_CODE (op) == FLOAT_EXTEND
|| (GET_CODE (op) == FLOAT
+ && SCALAR_FLOAT_MODE_P (GET_MODE (op))
&& ((unsigned)significand_size (GET_MODE (op))
>= (GET_MODE_BITSIZE (GET_MODE (XEXP (op, 0)))
- num_sign_bit_copies (XEXP (op, 0),
break;
case POPCOUNT:
+ switch (GET_CODE (op))
+ {
+ case BSWAP:
+ case ZERO_EXTEND:
+ /* (popcount (zero_extend <X>)) = (popcount <X>) */
+ return simplify_gen_unary (POPCOUNT, mode, XEXP (op, 0),
+ GET_MODE (XEXP (op, 0)));
+
+ case ROTATE:
+ case ROTATERT:
+ /* Rotations don't affect popcount. */
+ if (!side_effects_p (XEXP (op, 1)))
+ return simplify_gen_unary (POPCOUNT, mode, XEXP (op, 0),
+ GET_MODE (XEXP (op, 0)));
+ break;
+
+ default:
+ break;
+ }
+ break;
+
case PARITY:
- /* (pop* (zero_extend <X>)) = (pop* <X>) */
- if (GET_CODE (op) == ZERO_EXTEND)
- return simplify_gen_unary (code, mode, XEXP (op, 0),
- GET_MODE (XEXP (op, 0)));
+ switch (GET_CODE (op))
+ {
+ case NOT:
+ case BSWAP:
+ case ZERO_EXTEND:
+ case SIGN_EXTEND:
+ return simplify_gen_unary (PARITY, mode, XEXP (op, 0),
+ GET_MODE (XEXP (op, 0)));
+
+ case ROTATE:
+ case ROTATERT:
+ /* Rotations don't affect parity. */
+ if (!side_effects_p (XEXP (op, 1)))
+ return simplify_gen_unary (PARITY, mode, XEXP (op, 0),
+ GET_MODE (XEXP (op, 0)));
+ break;
+
+ default:
+ break;
+ }
+ break;
+
+ case BSWAP:
+ /* (bswap (bswap x)) -> x. */
+ if (GET_CODE (op) == BSWAP)
+ return XEXP (op, 0);
break;
case FLOAT:
break;
case BSWAP:
- return 0;
+ {
+ unsigned int s;
+
+ val = 0;
+ for (s = 0; s < width; s += 8)
+ {
+ unsigned int d = width - s - 8;
+ unsigned HOST_WIDE_INT byte;
+ byte = (arg0 >> s) & 0xff;
+ val |= byte << d;
+ }
+ }
+ break;
case TRUNCATE:
val = arg0;
lv &= 1;
break;
+ case BSWAP:
+ {
+ unsigned int s;
+
+ hv = 0;
+ lv = 0;
+ for (s = 0; s < width; s += 8)
+ {
+ unsigned int d = width - s - 8;
+ unsigned HOST_WIDE_INT byte;
+
+ if (s < HOST_BITS_PER_WIDE_INT)
+ byte = (l1 >> s) & 0xff;
+ else
+ byte = (h1 >> (s - HOST_BITS_PER_WIDE_INT)) & 0xff;
+
+ if (d < HOST_BITS_PER_WIDE_INT)
+ lv |= byte << d;
+ else
+ hv |= byte << (d - HOST_BITS_PER_WIDE_INT);
+ }
+ }
+ break;
+
case TRUNCATE:
/* This is just a change-of-mode, so do nothing. */
lv = l1, hv = h1;
XEXP (op0, 1)));
/* Canonicalize (plus (mult (neg B) C) A) to (minus A (mult B C)). */
- if (GET_CODE (op0) == MULT
+ if (!HONOR_SIGN_DEPENDENT_ROUNDING (mode)
+ && GET_CODE (op0) == MULT
&& GET_CODE (XEXP (op0, 0)) == NEG)
{
rtx in1, in2;
case MINUS:
/* We can't assume x-x is 0 even with non-IEEE floating point,
but since it is zero except in very strange circumstances, we
- will treat it as zero with -funsafe-math-optimizations. */
+ will treat it as zero with -funsafe-math-optimizations and
+ -ffinite-math-only. */
if (rtx_equal_p (trueop0, trueop1)
&& ! side_effects_p (op0)
- && (! FLOAT_MODE_P (mode) || flag_unsafe_math_optimizations))
+ && (! FLOAT_MODE_P (mode)
+ || (flag_unsafe_math_optimizations
+ && !HONOR_NANS (mode)
+ && !HONOR_INFINITIES (mode))))
return CONST0_RTX (mode);
/* Change subtraction from zero into negation. (0 - x) is the
return reversed;
/* Canonicalize (minus A (mult (neg B) C)) to (plus (mult B C) A). */
- if (GET_CODE (op1) == MULT
+ if (!HONOR_SIGN_DEPENDENT_ROUNDING (mode)
+ && GET_CODE (op1) == MULT
&& GET_CODE (XEXP (op1, 0)) == NEG)
{
rtx in1, in2;
/* Canonicalize (minus (neg A) (mult B C)) to
(minus (mult (neg B) C) A). */
- if (GET_CODE (op1) == MULT
+ if (!HONOR_SIGN_DEPENDENT_ROUNDING (mode)
+ && GET_CODE (op1) == MULT
&& GET_CODE (op0) == NEG)
{
rtx in1, in2;
&& (nonzero_bits (op0, mode) & ~INTVAL (op1)) == 0)
return op1;
+ /* Canonicalize (X & C1) | C2. */
+ if (GET_CODE (op0) == AND
+ && GET_CODE (trueop1) == CONST_INT
+ && GET_CODE (XEXP (op0, 1)) == CONST_INT)
+ {
+ HOST_WIDE_INT mask = GET_MODE_MASK (mode);
+ HOST_WIDE_INT c1 = INTVAL (XEXP (op0, 1));
+ HOST_WIDE_INT c2 = INTVAL (trueop1);
+
+ /* If (C1&C2) == C1, then (X&C1)|C2 becomes X. */
+ if ((c1 & c2) == c1
+ && !side_effects_p (XEXP (op0, 0)))
+ return trueop1;
+
+ /* If (C1|C2) == ~0 then (X&C1)|C2 becomes X|C2. */
+ if (((c1|c2) & mask) == mask)
+ return simplify_gen_binary (IOR, mode, XEXP (op0, 0), op1);
+
+ /* Minimize the number of bits set in C1, i.e. C1 := C1 & ~C2. */
+ if (((c1 & ~c2) & mask) != (c1 & mask))
+ {
+ tem = simplify_gen_binary (AND, mode, XEXP (op0, 0),
+ gen_int_mode (c1 & ~c2, mode));
+ return simplify_gen_binary (IOR, mode, tem, op1);
+ }
+ }
+
/* Convert (A & B) | A to A. */
if (GET_CODE (op0) == AND
&& (rtx_equal_p (XEXP (op0, 0), op1)
return simplify_gen_unary (ZERO_EXTEND, mode, tem, imode);
}
+ /* Canonicalize (A | C1) & C2 as (A & C2) | (C1 & C2). */
+ if (GET_CODE (op0) == IOR
+ && GET_CODE (trueop1) == CONST_INT
+ && GET_CODE (XEXP (op0, 1)) == CONST_INT)
+ {
+ HOST_WIDE_INT tmp = INTVAL (trueop1) & INTVAL (XEXP (op0, 1));
+ return simplify_gen_binary (IOR, mode,
+ simplify_gen_binary (AND, mode,
+ XEXP (op0, 0), op1),
+ gen_int_mode (tmp, mode));
+ }
+
/* Convert (A ^ B) & A to A & (~B) since the latter is often a single
insn (and may simplify more). */
if (GET_CODE (op0) == XOR
{
enum rtx_code op0code = GET_CODE (op0);
- if (GET_CODE (op1) == CONST_INT)
+ if (op1 == const0_rtx && COMPARISON_P (op0))
{
- if (INTVAL (op1) == 0 && COMPARISON_P (op0))
+ /* If op0 is a comparison, extract the comparison arguments
+ from it. */
+ if (code == NE)
{
- /* If op0 is a comparison, extract the comparison arguments
- from it. */
- if (code == NE)
- {
- if (GET_MODE (op0) == 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_code = reversed_comparison_code (op0, NULL_RTX);
- if (new_code != UNKNOWN)
- return simplify_gen_relational (new_code, mode, VOIDmode,
- XEXP (op0, 0), XEXP (op0, 1));
- }
+ if (GET_MODE (op0) == 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_code = reversed_comparison_code (op0, NULL_RTX);
+ if (new_code != UNKNOWN)
+ return simplify_gen_relational (new_code, mode, VOIDmode,
+ XEXP (op0, 0), XEXP (op0, 1));
+ }
+ }
+
+ if (op1 == const0_rtx)
+ {
+ /* Canonicalize (GTU x 0) as (NE x 0). */
+ if (code == GTU)
+ return simplify_gen_relational (NE, mode, cmp_mode, op0, op1);
+ /* Canonicalize (LEU x 0) as (EQ x 0). */
+ if (code == LEU)
+ return simplify_gen_relational (EQ, mode, cmp_mode, op0, op1);
+ }
+ else if (op1 == const1_rtx)
+ {
+ switch (code)
+ {
+ case GE:
+ /* Canonicalize (GE x 1) as (GT x 0). */
+ return simplify_gen_relational (GT, mode, cmp_mode,
+ op0, const0_rtx);
+ case GEU:
+ /* Canonicalize (GEU x 1) as (NE x 0). */
+ return simplify_gen_relational (NE, mode, cmp_mode,
+ op0, const0_rtx);
+ case LT:
+ /* Canonicalize (LT x 1) as (LE x 0). */
+ return simplify_gen_relational (LE, mode, cmp_mode,
+ op0, const0_rtx);
+ case LTU:
+ /* Canonicalize (LTU x 1) as (EQ x 0). */
+ return simplify_gen_relational (EQ, mode, cmp_mode,
+ op0, const0_rtx);
+ default:
+ break;
}
}
+ else if (op1 == constm1_rtx)
+ {
+ /* Canonicalize (LE x -1) as (LT x 0). */
+ if (code == LE)
+ return simplify_gen_relational (LT, mode, cmp_mode, op0, const0_rtx);
+ /* Canonicalize (GT x -1) as (GE x 0). */
+ if (code == GT)
+ return simplify_gen_relational (GE, mode, cmp_mode, op0, const0_rtx);
+ }
/* (eq/ne (plus x cst1) cst2) simplifies to (eq/ne x (cst2 - cst1)) */
if ((code == EQ || code == NE)
simplify_gen_binary (XOR, cmp_mode,
XEXP (op0, 1), op1));
+ if (op0code == POPCOUNT && op1 == const0_rtx)
+ switch (code)
+ {
+ case EQ:
+ case LE:
+ case LEU:
+ /* (eq (popcount x) (const_int 0)) -> (eq x (const_int 0)). */
+ return simplify_gen_relational (EQ, mode, GET_MODE (XEXP (op0, 0)),
+ XEXP (op0, 0), const0_rtx);
+
+ case NE:
+ case GT:
+ case GTU:
+ /* (ne (popcount x) (const_int 0)) -> (ne x (const_int 0)). */
+ return simplify_gen_relational (NE, mode, GET_MODE (XEXP (op0, 0)),
+ XEXP (op0, 0), const0_rtx);
+
+ default:
+ break;
+ }
+
return NULL_RTX;
}
/* Optimize abs(x) < 0.0. */
if (trueop1 == CONST0_RTX (mode)
&& !HONOR_SNANS (mode)
- && !(flag_wrapv && INTEGRAL_MODE_P (mode)))
+ && (!INTEGRAL_MODE_P (mode)
+ || (!flag_wrapv && !flag_trapv && flag_strict_overflow)))
{
tem = GET_CODE (trueop0) == FLOAT_EXTEND ? XEXP (trueop0, 0)
: trueop0;
if (GET_CODE (tem) == ABS)
- return const0_rtx;
+ {
+ if (INTEGRAL_MODE_P (mode)
+ && (issue_strict_overflow_warning
+ (WARN_STRICT_OVERFLOW_CONDITIONAL)))
+ warning (OPT_Wstrict_overflow,
+ ("assuming signed overflow does not occur when "
+ "assuming abs (x) < 0 is false"));
+ return const0_rtx;
+ }
}
+
+ /* Optimize popcount (x) < 0. */
+ if (GET_CODE (trueop0) == POPCOUNT && trueop1 == const0_rtx)
+ return const_true_rtx;
break;
case GE:
/* Optimize abs(x) >= 0.0. */
if (trueop1 == CONST0_RTX (mode)
&& !HONOR_NANS (mode)
- && !(flag_wrapv && INTEGRAL_MODE_P (mode)))
+ && (!INTEGRAL_MODE_P (mode)
+ || (!flag_wrapv && !flag_trapv && flag_strict_overflow)))
{
tem = GET_CODE (trueop0) == FLOAT_EXTEND ? XEXP (trueop0, 0)
: trueop0;
if (GET_CODE (tem) == ABS)
- return const_true_rtx;
+ {
+ if (INTEGRAL_MODE_P (mode)
+ && (issue_strict_overflow_warning
+ (WARN_STRICT_OVERFLOW_CONDITIONAL)))
+ warning (OPT_Wstrict_overflow,
+ ("assuming signed overflow does not occur when "
+ "assuming abs (x) >= 0 is true"));
+ return const_true_rtx;
+ }
}
+
+ /* Optimize popcount (x) >= 0. */
+ if (GET_CODE (trueop0) == POPCOUNT && trueop1 == const0_rtx)
+ return const_true_rtx;
break;
case UNGE:
of real and imaginary part. */
if (GET_CODE (op) == CONCAT)
{
- unsigned int inner_size, final_offset;
+ unsigned int part_size, final_offset;
rtx part, res;
- inner_size = GET_MODE_UNIT_SIZE (innermode);
- part = byte < inner_size ? XEXP (op, 0) : XEXP (op, 1);
- final_offset = byte % inner_size;
- if (final_offset + GET_MODE_SIZE (outermode) > inner_size)
+ part_size = GET_MODE_UNIT_SIZE (GET_MODE (XEXP (op, 0)));
+ if (byte < part_size)
+ {
+ part = XEXP (op, 0);
+ final_offset = byte;
+ }
+ else
+ {
+ part = XEXP (op, 1);
+ final_offset = byte - part_size;
+ }
+
+ if (final_offset + GET_MODE_SIZE (outermode) > part_size)
return NULL_RTX;
res = simplify_subreg (outermode, part, GET_MODE (part), final_offset);
case RTX_EXTRA:
if (code == SUBREG)
- return simplify_gen_subreg (mode, SUBREG_REG (x),
- GET_MODE (SUBREG_REG (x)),
- SUBREG_BYTE (x));
+ return simplify_subreg (mode, SUBREG_REG (x),
+ GET_MODE (SUBREG_REG (x)),
+ SUBREG_BYTE (x));
break;
case RTX_OBJ: