/* 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, 2007, 2008, 2009, 2010,
- 2011, 2012 Free Software Foundation, Inc.
+ Copyright (C) 1987-2014 Free Software Foundation, Inc.
This file is part of GCC.
#include "tm.h"
#include "rtl.h"
#include "tree.h"
+#include "varasm.h"
#include "tm_p.h"
#include "regs.h"
#include "hard-reg-set.h"
/* If we're accessing the constant in a different mode than it was
originally stored, attempt to fix that up via subreg simplifications.
If that fails we have no choice but to return the original memory. */
- if (offset != 0 || cmode != GET_MODE (x))
+ if ((offset != 0 || cmode != GET_MODE (x))
+ && offset >= 0 && offset < GET_MODE_SIZE (cmode))
{
rtx tem = simplify_subreg (GET_MODE (x), c, cmode, offset);
if (tem && CONSTANT_P (tem))
&mode, &unsignedp, &volatilep, false);
if (bitsize != GET_MODE_BITSIZE (mode)
|| (bitpos % BITS_PER_UNIT)
- || (toffset && !host_integerp (toffset, 0)))
+ || (toffset && !tree_fits_shwi_p (toffset)))
decl = NULL;
else
{
offset += bitpos / BITS_PER_UNIT;
if (toffset)
- offset += TREE_INT_CST_LOW (toffset);
+ offset += tree_to_shwi (toffset);
}
break;
}
return simplify_replace_fn_rtx (x, old_rtx, 0, new_rtx);
}
\f
+/* Try to simplify a MODE truncation of OP, which has OP_MODE.
+ Only handle cases where the truncated value is inherently an rvalue.
+
+ RTL provides two ways of truncating a value:
+
+ 1. a lowpart subreg. This form is only a truncation when both
+ the outer and inner modes (here MODE and OP_MODE respectively)
+ are scalar integers, and only then when the subreg is used as
+ an rvalue.
+
+ It is only valid to form such truncating subregs if the
+ truncation requires no action by the target. The onus for
+ proving this is on the creator of the subreg -- e.g. the
+ caller to simplify_subreg or simplify_gen_subreg -- and typically
+ involves either TRULY_NOOP_TRUNCATION_MODES_P or truncated_to_mode.
+
+ 2. a TRUNCATE. This form handles both scalar and compound integers.
+
+ The first form is preferred where valid. However, the TRUNCATE
+ handling in simplify_unary_operation turns the second form into the
+ first form when TRULY_NOOP_TRUNCATION_MODES_P or truncated_to_mode allow,
+ so it is generally safe to form rvalue truncations using:
+
+ simplify_gen_unary (TRUNCATE, ...)
+
+ and leave simplify_unary_operation to work out which representation
+ should be used.
+
+ Because of the proof requirements on (1), simplify_truncation must
+ also use simplify_gen_unary (TRUNCATE, ...) to truncate parts of OP,
+ regardless of whether the outer truncation came from a SUBREG or a
+ TRUNCATE. For example, if the caller has proven that an SImode
+ truncation of:
+
+ (and:DI X Y)
+
+ is a no-op and can be represented as a subreg, it does not follow
+ that SImode truncations of X and Y are also no-ops. On a target
+ like 64-bit MIPS that requires SImode values to be stored in
+ sign-extended form, an SImode truncation of:
+
+ (and:DI (reg:DI X) (const_int 63))
+
+ is trivially a no-op because only the lower 6 bits can be set.
+ However, X is still an arbitrary 64-bit number and so we cannot
+ assume that truncating it too is a no-op. */
+
+static rtx
+simplify_truncation (enum machine_mode mode, rtx op,
+ enum machine_mode op_mode)
+{
+ unsigned int precision = GET_MODE_UNIT_PRECISION (mode);
+ unsigned int op_precision = GET_MODE_UNIT_PRECISION (op_mode);
+ gcc_assert (precision <= op_precision);
+
+ /* Optimize truncations of zero and sign extended values. */
+ if (GET_CODE (op) == ZERO_EXTEND
+ || GET_CODE (op) == SIGN_EXTEND)
+ {
+ /* There are three possibilities. If MODE is the same as the
+ origmode, we can omit both the extension and the subreg.
+ If MODE is not larger than the origmode, we can apply the
+ truncation without the extension. Finally, if the outermode
+ is larger than the origmode, we can just extend to the appropriate
+ mode. */
+ enum machine_mode origmode = GET_MODE (XEXP (op, 0));
+ if (mode == origmode)
+ return XEXP (op, 0);
+ else if (precision <= GET_MODE_UNIT_PRECISION (origmode))
+ return simplify_gen_unary (TRUNCATE, mode,
+ XEXP (op, 0), origmode);
+ else
+ return simplify_gen_unary (GET_CODE (op), mode,
+ XEXP (op, 0), origmode);
+ }
+
+ /* If the machine can perform operations in the truncated mode, distribute
+ the truncation, i.e. simplify (truncate:QI (op:SI (x:SI) (y:SI))) into
+ (op:QI (truncate:QI (x:SI)) (truncate:QI (y:SI))). */
+ if (1
+#ifdef WORD_REGISTER_OPERATIONS
+ && precision >= BITS_PER_WORD
+#endif
+ && (GET_CODE (op) == PLUS
+ || GET_CODE (op) == MINUS
+ || GET_CODE (op) == MULT))
+ {
+ rtx op0 = simplify_gen_unary (TRUNCATE, mode, XEXP (op, 0), op_mode);
+ if (op0)
+ {
+ rtx op1 = simplify_gen_unary (TRUNCATE, mode, XEXP (op, 1), op_mode);
+ if (op1)
+ return simplify_gen_binary (GET_CODE (op), mode, op0, op1);
+ }
+ }
+
+ /* Simplify (truncate:QI (lshiftrt:SI (sign_extend:SI (x:QI)) C)) into
+ to (ashiftrt:QI (x:QI) C), where C is a suitable small constant and
+ the outer subreg is effectively a truncation to the original mode. */
+ if ((GET_CODE (op) == LSHIFTRT
+ || GET_CODE (op) == ASHIFTRT)
+ /* Ensure that OP_MODE is at least twice as wide as MODE
+ to avoid the possibility that an outer LSHIFTRT shifts by more
+ than the sign extension's sign_bit_copies and introduces zeros
+ into the high bits of the result. */
+ && 2 * precision <= op_precision
+ && CONST_INT_P (XEXP (op, 1))
+ && GET_CODE (XEXP (op, 0)) == SIGN_EXTEND
+ && GET_MODE (XEXP (XEXP (op, 0), 0)) == mode
+ && UINTVAL (XEXP (op, 1)) < precision)
+ return simplify_gen_binary (ASHIFTRT, mode,
+ XEXP (XEXP (op, 0), 0), XEXP (op, 1));
+
+ /* Likewise (truncate:QI (lshiftrt:SI (zero_extend:SI (x:QI)) C)) into
+ to (lshiftrt:QI (x:QI) C), where C is a suitable small constant and
+ the outer subreg is effectively a truncation to the original mode. */
+ if ((GET_CODE (op) == LSHIFTRT
+ || GET_CODE (op) == ASHIFTRT)
+ && CONST_INT_P (XEXP (op, 1))
+ && GET_CODE (XEXP (op, 0)) == ZERO_EXTEND
+ && GET_MODE (XEXP (XEXP (op, 0), 0)) == mode
+ && UINTVAL (XEXP (op, 1)) < precision)
+ return simplify_gen_binary (LSHIFTRT, mode,
+ XEXP (XEXP (op, 0), 0), XEXP (op, 1));
+
+ /* Likewise (truncate:QI (ashift:SI (zero_extend:SI (x:QI)) C)) into
+ to (ashift:QI (x:QI) C), where C is a suitable small constant and
+ the outer subreg is effectively a truncation to the original mode. */
+ if (GET_CODE (op) == ASHIFT
+ && CONST_INT_P (XEXP (op, 1))
+ && (GET_CODE (XEXP (op, 0)) == ZERO_EXTEND
+ || GET_CODE (XEXP (op, 0)) == SIGN_EXTEND)
+ && GET_MODE (XEXP (XEXP (op, 0), 0)) == mode
+ && UINTVAL (XEXP (op, 1)) < precision)
+ return simplify_gen_binary (ASHIFT, mode,
+ XEXP (XEXP (op, 0), 0), XEXP (op, 1));
+
+ /* Recognize a word extraction from a multi-word subreg. */
+ if ((GET_CODE (op) == LSHIFTRT
+ || GET_CODE (op) == ASHIFTRT)
+ && SCALAR_INT_MODE_P (mode)
+ && SCALAR_INT_MODE_P (op_mode)
+ && precision >= BITS_PER_WORD
+ && 2 * precision <= op_precision
+ && CONST_INT_P (XEXP (op, 1))
+ && (INTVAL (XEXP (op, 1)) & (precision - 1)) == 0
+ && UINTVAL (XEXP (op, 1)) < op_precision)
+ {
+ int byte = subreg_lowpart_offset (mode, op_mode);
+ int shifted_bytes = INTVAL (XEXP (op, 1)) / BITS_PER_UNIT;
+ return simplify_gen_subreg (mode, XEXP (op, 0), op_mode,
+ (WORDS_BIG_ENDIAN
+ ? byte - shifted_bytes
+ : byte + shifted_bytes));
+ }
+
+ /* If we have a TRUNCATE of a right shift of MEM, make a new MEM
+ and try replacing the TRUNCATE and shift with it. Don't do this
+ if the MEM has a mode-dependent address. */
+ if ((GET_CODE (op) == LSHIFTRT
+ || GET_CODE (op) == ASHIFTRT)
+ && SCALAR_INT_MODE_P (op_mode)
+ && MEM_P (XEXP (op, 0))
+ && CONST_INT_P (XEXP (op, 1))
+ && (INTVAL (XEXP (op, 1)) % GET_MODE_BITSIZE (mode)) == 0
+ && INTVAL (XEXP (op, 1)) > 0
+ && INTVAL (XEXP (op, 1)) < GET_MODE_BITSIZE (op_mode)
+ && ! mode_dependent_address_p (XEXP (XEXP (op, 0), 0),
+ MEM_ADDR_SPACE (XEXP (op, 0)))
+ && ! MEM_VOLATILE_P (XEXP (op, 0))
+ && (GET_MODE_SIZE (mode) >= UNITS_PER_WORD
+ || WORDS_BIG_ENDIAN == BYTES_BIG_ENDIAN))
+ {
+ int byte = subreg_lowpart_offset (mode, op_mode);
+ int shifted_bytes = INTVAL (XEXP (op, 1)) / BITS_PER_UNIT;
+ return adjust_address_nv (XEXP (op, 0), mode,
+ (WORDS_BIG_ENDIAN
+ ? byte - shifted_bytes
+ : byte + shifted_bytes));
+ }
+
+ /* (truncate:SI (OP:DI ({sign,zero}_extend:DI foo:SI))) is
+ (OP:SI foo:SI) if OP is NEG or ABS. */
+ if ((GET_CODE (op) == ABS
+ || GET_CODE (op) == NEG)
+ && (GET_CODE (XEXP (op, 0)) == SIGN_EXTEND
+ || GET_CODE (XEXP (op, 0)) == ZERO_EXTEND)
+ && GET_MODE (XEXP (XEXP (op, 0), 0)) == mode)
+ return simplify_gen_unary (GET_CODE (op), mode,
+ XEXP (XEXP (op, 0), 0), mode);
+
+ /* (truncate:A (subreg:B (truncate:C X) 0)) is
+ (truncate:A X). */
+ if (GET_CODE (op) == SUBREG
+ && SCALAR_INT_MODE_P (mode)
+ && SCALAR_INT_MODE_P (op_mode)
+ && SCALAR_INT_MODE_P (GET_MODE (SUBREG_REG (op)))
+ && GET_CODE (SUBREG_REG (op)) == TRUNCATE
+ && subreg_lowpart_p (op))
+ {
+ rtx inner = XEXP (SUBREG_REG (op), 0);
+ if (GET_MODE_PRECISION (mode)
+ <= GET_MODE_PRECISION (GET_MODE (SUBREG_REG (op))))
+ return simplify_gen_unary (TRUNCATE, mode, inner, GET_MODE (inner));
+ else
+ /* If subreg above is paradoxical and C is narrower
+ than A, return (subreg:A (truncate:C X) 0). */
+ return simplify_gen_subreg (mode, SUBREG_REG (op),
+ GET_MODE (SUBREG_REG (op)), 0);
+ }
+
+ /* (truncate:A (truncate:B X)) is (truncate:A X). */
+ if (GET_CODE (op) == TRUNCATE)
+ return simplify_gen_unary (TRUNCATE, mode, XEXP (op, 0),
+ GET_MODE (XEXP (op, 0)));
+
+ return NULL_RTX;
+}
+\f
/* Try to simplify a unary operation CODE whose output mode is to be
MODE with input operand OP whose mode was originally OP_MODE.
Return zero if no simplification can be made. */
/* Similarly, (not (neg X)) is (plus X -1). */
if (GET_CODE (op) == NEG)
- return plus_constant (mode, XEXP (op, 0), -1);
+ return simplify_gen_binary (PLUS, mode, XEXP (op, 0),
+ CONSTM1_RTX (mode));
/* (not (xor X C)) for C constant is (xor X D) with D = ~C. */
if (GET_CODE (op) == XOR
/* (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))
simplify_gen_unary (NOT, inner_mode, const1_rtx,
inner_mode),
XEXP (SUBREG_REG (op), 1));
- return rtl_hooks.gen_lowpart_no_emit (mode, x);
+ temp = rtl_hooks.gen_lowpart_no_emit (mode, x);
+ if (temp)
+ return temp;
}
/* Apply De Morgan's laws to reduce number of patterns for machines
with negating logical insns (and-not, nand, etc.). If result has
only one NOT, put it first, since that is how the patterns are
coded. */
-
if (GET_CODE (op) == IOR || GET_CODE (op) == AND)
{
rtx in1 = XEXP (op, 0), in2 = XEXP (op, 1);
return gen_rtx_fmt_ee (GET_CODE (op) == IOR ? AND : IOR,
mode, in1, in2);
}
+
+ /* (not (bswap x)) -> (bswap (not x)). */
+ if (GET_CODE (op) == BSWAP)
+ {
+ rtx x = simplify_gen_unary (NOT, mode, XEXP (op, 0), mode);
+ return simplify_gen_unary (BSWAP, mode, x, mode);
+ }
break;
case NEG:
/* Similarly, (neg (not X)) is (plus X 1). */
if (GET_CODE (op) == NOT)
- return plus_constant (mode, XEXP (op, 0), 1);
+ return simplify_gen_binary (PLUS, mode, XEXP (op, 0),
+ CONST1_RTX (mode));
/* (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
&& !HONOR_SIGN_DEPENDENT_ROUNDING (mode))
{
/* (neg (plus A C)) is simplified to (minus -C A). */
- if (CONST_INT_P (XEXP (op, 1))
- || CONST_DOUBLE_P (XEXP (op, 1)))
+ if (CONST_SCALAR_INT_P (XEXP (op, 1))
+ || CONST_DOUBLE_AS_FLOAT_P (XEXP (op, 1)))
{
temp = simplify_unary_operation (NEG, mode, XEXP (op, 1), mode);
if (temp)
break;
case TRUNCATE:
- /* We can't handle truncation to a partial integer mode here
- because we don't know the real bitsize of the partial
- integer mode. */
- if (GET_MODE_CLASS (mode) == MODE_PARTIAL_INT)
- break;
-
- /* (truncate:SI ({sign,zero}_extend:DI foo:SI)) == foo:SI. */
- if ((GET_CODE (op) == SIGN_EXTEND
- || GET_CODE (op) == ZERO_EXTEND)
- && GET_MODE (XEXP (op, 0)) == mode)
- return XEXP (op, 0);
+ /* Don't optimize (lshiftrt (mult ...)) as it would interfere
+ with the umulXi3_highpart patterns. */
+ if (GET_CODE (op) == LSHIFTRT
+ && GET_CODE (XEXP (op, 0)) == MULT)
+ break;
- /* (truncate:SI (OP:DI ({sign,zero}_extend:DI foo:SI))) is
- (OP:SI foo:SI) if OP is NEG or ABS. */
- if ((GET_CODE (op) == ABS
- || GET_CODE (op) == NEG)
- && (GET_CODE (XEXP (op, 0)) == SIGN_EXTEND
- || GET_CODE (XEXP (op, 0)) == ZERO_EXTEND)
- && GET_MODE (XEXP (XEXP (op, 0), 0)) == mode)
- return simplify_gen_unary (GET_CODE (op), mode,
- XEXP (XEXP (op, 0), 0), mode);
+ if (GET_MODE_CLASS (mode) == MODE_PARTIAL_INT)
+ {
+ if (TRULY_NOOP_TRUNCATION_MODES_P (mode, GET_MODE (op)))
+ {
+ temp = rtl_hooks.gen_lowpart_no_emit (mode, op);
+ if (temp)
+ return temp;
+ }
+ /* We can't handle truncation to a partial integer mode here
+ because we don't know the real bitsize of the partial
+ integer mode. */
+ break;
+ }
- /* (truncate:A (subreg:B (truncate:C X) 0)) is
- (truncate:A X). */
- if (GET_CODE (op) == SUBREG
- && GET_CODE (SUBREG_REG (op)) == TRUNCATE
- && subreg_lowpart_p (op))
- return simplify_gen_unary (TRUNCATE, mode, XEXP (SUBREG_REG (op), 0),
- GET_MODE (XEXP (SUBREG_REG (op), 0)));
+ if (GET_MODE (op) != VOIDmode)
+ {
+ temp = simplify_truncation (mode, op, GET_MODE (op));
+ if (temp)
+ return temp;
+ }
/* If we know that the value is already truncated, we can
- replace the TRUNCATE with a SUBREG. Note that this is also
- valid if TRULY_NOOP_TRUNCATION is false for the corresponding
- modes we just have to apply a different definition for
- truncation. But don't do this for an (LSHIFTRT (MULT ...))
- since this will cause problems with the umulXi3_highpart
- patterns. */
- if ((TRULY_NOOP_TRUNCATION_MODES_P (mode, GET_MODE (op))
- ? (num_sign_bit_copies (op, GET_MODE (op))
- > (unsigned int) (GET_MODE_PRECISION (GET_MODE (op))
- - GET_MODE_PRECISION (mode)))
- : truncated_to_mode (mode, op))
- && ! (GET_CODE (op) == LSHIFTRT
- && GET_CODE (XEXP (op, 0)) == MULT))
- return rtl_hooks.gen_lowpart_no_emit (mode, op);
+ replace the TRUNCATE with a SUBREG. */
+ if (GET_MODE_NUNITS (mode) == 1
+ && (TRULY_NOOP_TRUNCATION_MODES_P (mode, GET_MODE (op))
+ || truncated_to_mode (mode, op)))
+ {
+ temp = rtl_hooks.gen_lowpart_no_emit (mode, op);
+ if (temp)
+ return temp;
+ }
/* A truncate of a comparison can be replaced with a subreg if
STORE_FLAG_VALUE permits. This is like the previous test,
if (HWI_COMPUTABLE_MODE_P (mode)
&& COMPARISON_P (op)
&& (STORE_FLAG_VALUE & ~GET_MODE_MASK (mode)) == 0)
- return rtl_hooks.gen_lowpart_no_emit (mode, op);
+ {
+ temp = rtl_hooks.gen_lowpart_no_emit (mode, op);
+ if (temp)
+ return temp;
+ }
/* A truncate of a memory is just loading the low part of the memory
if we are not changing the meaning of the address. */
&& !VECTOR_MODE_P (mode)
&& !MEM_VOLATILE_P (op)
&& !mode_dependent_address_p (XEXP (op, 0), MEM_ADDR_SPACE (op)))
- return rtl_hooks.gen_lowpart_no_emit (mode, op);
+ {
+ temp = rtl_hooks.gen_lowpart_no_emit (mode, op);
+ if (temp)
+ return temp;
+ }
break;
&& SUBREG_PROMOTED_VAR_P (op)
&& ! SUBREG_PROMOTED_UNSIGNED_P (op)
&& GET_MODE_SIZE (mode) <= GET_MODE_SIZE (GET_MODE (XEXP (op, 0))))
- return rtl_hooks.gen_lowpart_no_emit (mode, op);
+ {
+ temp = rtl_hooks.gen_lowpart_no_emit (mode, op);
+ if (temp)
+ return temp;
+ }
/* (sign_extend:M (sign_extend:N <X>)) is (sign_extend:M <X>).
(sign_extend:M (zero_extend:N <X>)) is (zero_extend:M <X>). */
{
rtx inner =
rtl_hooks.gen_lowpart_no_emit (tmode, XEXP (XEXP (op, 0), 0));
- return simplify_gen_unary (GET_CODE (op) == ASHIFTRT
- ? SIGN_EXTEND : ZERO_EXTEND,
- mode, inner, tmode);
+ if (inner)
+ return simplify_gen_unary (GET_CODE (op) == ASHIFTRT
+ ? SIGN_EXTEND : ZERO_EXTEND,
+ mode, inner, tmode);
}
}
&& SUBREG_PROMOTED_VAR_P (op)
&& SUBREG_PROMOTED_UNSIGNED_P (op) > 0
&& GET_MODE_SIZE (mode) <= GET_MODE_SIZE (GET_MODE (XEXP (op, 0))))
- return rtl_hooks.gen_lowpart_no_emit (mode, op);
+ {
+ temp = rtl_hooks.gen_lowpart_no_emit (mode, op);
+ if (temp)
+ return temp;
+ }
/* Extending a widening multiplication should be canonicalized to
a wider widening multiplication. */
{
rtx inner =
rtl_hooks.gen_lowpart_no_emit (tmode, XEXP (XEXP (op, 0), 0));
- return simplify_gen_unary (ZERO_EXTEND, mode, inner, tmode);
+ if (inner)
+ return simplify_gen_unary (ZERO_EXTEND, mode, inner, tmode);
}
}
+ /* (zero_extend:M (subreg:N <X:O>)) is <X:O> (for M == O) or
+ (zero_extend:M <X:O>), if X doesn't have any non-zero bits outside
+ of mode N. E.g.
+ (zero_extend:SI (subreg:QI (and:SI (reg:SI) (const_int 63)) 0)) is
+ (and:SI (reg:SI) (const_int 63)). */
+ if (GET_CODE (op) == SUBREG
+ && GET_MODE_PRECISION (GET_MODE (op))
+ < GET_MODE_PRECISION (GET_MODE (SUBREG_REG (op)))
+ && GET_MODE_PRECISION (GET_MODE (SUBREG_REG (op)))
+ <= HOST_BITS_PER_WIDE_INT
+ && GET_MODE_PRECISION (mode)
+ >= GET_MODE_PRECISION (GET_MODE (SUBREG_REG (op)))
+ && subreg_lowpart_p (op)
+ && (nonzero_bits (SUBREG_REG (op), GET_MODE (SUBREG_REG (op)))
+ & ~GET_MODE_MASK (GET_MODE (op))) == 0)
+ {
+ if (GET_MODE_PRECISION (mode)
+ == GET_MODE_PRECISION (GET_MODE (SUBREG_REG (op))))
+ return SUBREG_REG (op);
+ return simplify_gen_unary (ZERO_EXTEND, mode, SUBREG_REG (op),
+ GET_MODE (SUBREG_REG (op)));
+ }
+
#if defined(POINTERS_EXTEND_UNSIGNED) && !defined(HAVE_ptr_extend)
/* As we do not know which address space the pointer is referring to,
we can do this only if the target does not support different pointer
gcc_assert (GET_MODE_INNER (mode) == GET_MODE_INNER
(GET_MODE (op)));
}
- if (CONST_INT_P (op) || CONST_DOUBLE_P (op)
+ if (CONST_SCALAR_INT_P (op) || CONST_DOUBLE_AS_FLOAT_P (op)
|| GET_CODE (op) == CONST_VECTOR)
{
int elt_size = GET_MODE_SIZE (GET_MODE_INNER (mode));
check the wrong mode (input vs. output) for a conversion operation,
such as FIX. At some point, this should be simplified. */
- if (code == FLOAT && (CONST_DOUBLE_AS_INT_P (op) || CONST_INT_P (op)))
+ if (code == FLOAT && CONST_SCALAR_INT_P (op))
{
HOST_WIDE_INT hv, lv;
REAL_VALUE_TYPE d;
d = real_value_truncate (mode, d);
return CONST_DOUBLE_FROM_REAL_VALUE (d, mode);
}
- else if (code == UNSIGNED_FLOAT
- && (CONST_DOUBLE_AS_INT_P (op) || CONST_INT_P (op)))
+ else if (code == UNSIGNED_FLOAT && CONST_SCALAR_INT_P (op))
{
HOST_WIDE_INT hv, lv;
REAL_VALUE_TYPE d;
break;
case NEG:
- val = - arg0;
+ val = - (unsigned HOST_WIDE_INT) arg0;
break;
case ABS:
&& SCALAR_FLOAT_MODE_P (mode)
&& SCALAR_FLOAT_MODE_P (GET_MODE (op)))
{
- REAL_VALUE_TYPE d, t;
+ REAL_VALUE_TYPE d;
REAL_VALUE_FROM_CONST_DOUBLE (d, op);
switch (code)
{
case SQRT:
- if (HONOR_SNANS (mode) && real_isnan (&d))
- return 0;
- real_sqrt (&t, mode, &d);
- d = t;
- break;
+ return 0;
case ABS:
d = real_value_abs (&d);
break;
/* Test against the signed lower bound. */
if (width > HOST_BITS_PER_WIDE_INT)
{
- th = (unsigned HOST_WIDE_INT) (-1)
- << (width - HOST_BITS_PER_WIDE_INT - 1);
+ th = HOST_WIDE_INT_M1U << (width - HOST_BITS_PER_WIDE_INT - 1);
tl = 0;
}
else
{
th = -1;
- tl = (unsigned HOST_WIDE_INT) (-1) << (width - 1);
+ tl = HOST_WIDE_INT_M1U << (width - 1);
}
real_from_integer (&t, VOIDmode, tl, th, 0);
if (REAL_VALUES_LESS (x, t))
return NULL_RTX;
}
\f
+/* Subroutine of simplify_binary_operation to simplify a binary operation
+ CODE that can commute with byte swapping, with result mode MODE and
+ operating on OP0 and OP1. CODE is currently one of AND, IOR or XOR.
+ Return zero if no simplification or canonicalization is possible. */
+
+static rtx
+simplify_byte_swapping_operation (enum rtx_code code, enum machine_mode mode,
+ rtx op0, rtx op1)
+{
+ rtx tem;
+
+ /* (op (bswap x) C1)) -> (bswap (op x C2)) with C2 swapped. */
+ if (GET_CODE (op0) == BSWAP && CONST_SCALAR_INT_P (op1))
+ {
+ tem = simplify_gen_binary (code, mode, XEXP (op0, 0),
+ simplify_gen_unary (BSWAP, mode, op1, mode));
+ return simplify_gen_unary (BSWAP, mode, tem, mode);
+ }
+
+ /* (op (bswap x) (bswap y)) -> (bswap (op x y)). */
+ if (GET_CODE (op0) == BSWAP && GET_CODE (op1) == BSWAP)
+ {
+ tem = simplify_gen_binary (code, mode, XEXP (op0, 0), XEXP (op1, 0));
+ return simplify_gen_unary (BSWAP, mode, tem, mode);
+ }
+
+ return NULL_RTX;
+}
+
/* 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,
}
/* (plus (xor X C1) C2) is (xor X (C1^C2)) if C2 is signbit. */
- if ((CONST_INT_P (op1) || CONST_DOUBLE_AS_INT_P (op1))
+ if (CONST_SCALAR_INT_P (op1)
&& GET_CODE (op0) == XOR
- && (CONST_INT_P (XEXP (op0, 1))
- || CONST_DOUBLE_AS_INT_P (XEXP (op0, 1)))
+ && CONST_SCALAR_INT_P (XEXP (op0, 1))
&& mode_signbit_p (mode, op1))
return simplify_gen_binary (XOR, mode, XEXP (op0, 0),
simplify_gen_binary (XOR, mode, op1,
/* (-x - c) may be simplified as (-c - x). */
if (GET_CODE (op0) == NEG
- && (CONST_INT_P (op1) || CONST_DOUBLE_P (op1)))
+ && (CONST_SCALAR_INT_P (op1) || CONST_DOUBLE_AS_FLOAT_P (op1)))
{
tem = simplify_unary_operation (NEG, mode, op1, mode);
if (tem)
&& CONST_INT_P (XEXP (op0, 1))
&& CONST_INT_P (op1)
&& (UINTVAL (XEXP (op0, 1)) & UINTVAL (op1)) != 0)
- return simplify_gen_binary (IOR, mode,
- simplify_gen_binary
- (AND, mode, XEXP (op0, 0),
- GEN_INT (UINTVAL (XEXP (op0, 1))
- & ~UINTVAL (op1))),
- op1);
+ {
+ rtx tmp = simplify_gen_binary (AND, mode, XEXP (op0, 0),
+ gen_int_mode (UINTVAL (XEXP (op0, 1))
+ & ~UINTVAL (op1),
+ mode));
+ return simplify_gen_binary (IOR, mode, tmp, op1);
+ }
/* If OP0 is (ashiftrt (plus ...) C), it might actually be
a (sign_extend (plus ...)). Then check if OP1 is a CONST_INT and
HOST_WIDE_INT mask = INTVAL (trueop1) << count;
if (mask >> count == INTVAL (trueop1)
+ && trunc_int_for_mode (mask, mode) == mask
&& (mask & nonzero_bits (XEXP (op0, 0), mode)) == 0)
return simplify_gen_binary (ASHIFTRT, mode,
plus_constant (mode, XEXP (op0, 0),
XEXP (op0, 1));
}
+ tem = simplify_byte_swapping_operation (code, mode, op0, op1);
+ if (tem)
+ return tem;
+
tem = simplify_associative_operation (code, mode, op0, op1);
if (tem)
return tem;
return CONST0_RTX (mode);
/* Canonicalize XOR of the most significant bit to PLUS. */
- if ((CONST_INT_P (op1) || CONST_DOUBLE_AS_INT_P (op1))
+ if (CONST_SCALAR_INT_P (op1)
&& 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 ((CONST_INT_P (op1) || CONST_DOUBLE_AS_INT_P (op1))
+ if (CONST_SCALAR_INT_P (op1)
&& GET_CODE (op0) == PLUS
- && (CONST_INT_P (XEXP (op0, 1))
- || CONST_DOUBLE_AS_INT_P (XEXP (op0, 1)))
+ && CONST_SCALAR_INT_P (XEXP (op0, 1))
&& mode_signbit_p (mode, XEXP (op0, 1)))
return simplify_gen_binary (XOR, mode, XEXP (op0, 0),
simplify_gen_binary (XOR, mode, op1,
/* Try to simplify ~A&C | ~B&C. */
if (na_c != NULL_RTX)
return simplify_gen_binary (IOR, mode, na_c,
- GEN_INT (~bval & cval));
+ gen_int_mode (~bval & cval, mode));
}
else
{
if (na_c == const0_rtx)
{
rtx a_nc_b = simplify_gen_binary (AND, mode, a,
- GEN_INT (~cval & bval));
+ gen_int_mode (~cval & bval,
+ mode));
return simplify_gen_binary (IOR, mode, a_nc_b,
- GEN_INT (~bval & cval));
+ gen_int_mode (~bval & cval,
+ mode));
}
}
}
&& (reversed = reversed_comparison (op0, mode)))
return reversed;
+ tem = simplify_byte_swapping_operation (code, mode, op0, op1);
+ if (tem)
+ return tem;
+
tem = simplify_associative_operation (code, mode, op0, op1);
if (tem)
return tem;
&& op1 == XEXP (XEXP (op0, 0), 0))
return simplify_gen_binary (AND, mode, op1, XEXP (op0, 1));
+ tem = simplify_byte_swapping_operation (code, mode, op0, op1);
+ if (tem)
+ return tem;
+
tem = simplify_associative_operation (code, mode, op0, op1);
if (tem)
return tem;
}
/* x/1 is x. */
if (trueop1 == CONST1_RTX (mode))
- return rtl_hooks.gen_lowpart_no_emit (mode, op0);
+ {
+ tem = rtl_hooks.gen_lowpart_no_emit (mode, op0);
+ if (tem)
+ return tem;
+ }
/* Convert divide by power of two into shift. */
if (CONST_INT_P (trueop1)
&& (val = exact_log2 (UINTVAL (trueop1))) > 0)
}
/* x/1 is x. */
if (trueop1 == CONST1_RTX (mode))
- return rtl_hooks.gen_lowpart_no_emit (mode, op0);
+ {
+ tem = rtl_hooks.gen_lowpart_no_emit (mode, op0);
+ if (tem)
+ return tem;
+ }
/* x/-1 is -x. */
if (trueop1 == constm1_rtx)
{
rtx x = rtl_hooks.gen_lowpart_no_emit (mode, op0);
- return simplify_gen_unary (NEG, mode, x, mode);
+ if (x)
+ return simplify_gen_unary (NEG, mode, x, mode);
}
}
break;
if (CONST_INT_P (trueop1)
&& exact_log2 (UINTVAL (trueop1)) > 0)
return simplify_gen_binary (AND, mode, op0,
- GEN_INT (INTVAL (op1) - 1));
+ gen_int_mode (INTVAL (op1) - 1, mode));
break;
case MOD:
case ROTATERT:
case ROTATE:
+ /* Canonicalize rotates by constant amount. If op1 is bitsize / 2,
+ prefer left rotation, if op1 is from bitsize / 2 + 1 to
+ bitsize - 1, use other direction of rotate with 1 .. bitsize / 2 - 1
+ amount instead. */
+ if (CONST_INT_P (trueop1)
+ && IN_RANGE (INTVAL (trueop1),
+ GET_MODE_BITSIZE (mode) / 2 + (code == ROTATE),
+ GET_MODE_BITSIZE (mode) - 1))
+ return simplify_gen_binary (code == ROTATE ? ROTATERT : ROTATE,
+ mode, op0, GEN_INT (GET_MODE_BITSIZE (mode)
+ - INTVAL (trueop1)));
+ /* FALLTHRU */
case ASHIFTRT:
if (trueop1 == CONST0_RTX (mode))
return op0;
return vec;
}
+ /* If we select elements in a vec_merge that all come from the same
+ operand, select from that operand directly. */
+ if (GET_CODE (op0) == VEC_MERGE)
+ {
+ rtx trueop02 = avoid_constant_pool_reference (XEXP (op0, 2));
+ if (CONST_INT_P (trueop02))
+ {
+ unsigned HOST_WIDE_INT sel = UINTVAL (trueop02);
+ bool all_operand0 = true;
+ bool all_operand1 = true;
+ for (int i = 0; i < XVECLEN (trueop1, 0); i++)
+ {
+ rtx j = XVECEXP (trueop1, 0, i);
+ if (sel & (1 << UINTVAL (j)))
+ all_operand1 = false;
+ else
+ all_operand0 = false;
+ }
+ if (all_operand0 && !side_effects_p (XEXP (op0, 1)))
+ return simplify_gen_binary (VEC_SELECT, mode, XEXP (op0, 0), op1);
+ if (all_operand1 && !side_effects_p (XEXP (op0, 0)))
+ return simplify_gen_binary (VEC_SELECT, mode, XEXP (op0, 1), op1);
+ }
+ }
+
return 0;
case VEC_CONCAT:
{
gcc_assert (GET_MODE_INNER (mode) == op1_mode);
if ((GET_CODE (trueop0) == CONST_VECTOR
- || CONST_INT_P (trueop0) || CONST_DOUBLE_P (trueop0))
+ || CONST_SCALAR_INT_P (trueop0)
+ || CONST_DOUBLE_AS_FLOAT_P (trueop0))
&& (GET_CODE (trueop1) == CONST_VECTOR
- || CONST_INT_P (trueop1) || CONST_DOUBLE_P (trueop1)))
+ || CONST_SCALAR_INT_P (trueop1)
+ || CONST_DOUBLE_AS_FLOAT_P (trueop1)))
{
int elt_size = GET_MODE_SIZE (GET_MODE_INNER (mode));
unsigned n_elts = (GET_MODE_SIZE (mode) / elt_size);
return gen_rtx_CONST_VECTOR (mode, v);
}
- /* Try to merge VEC_SELECTs from the same vector into a single one. */
+ /* Try to merge two VEC_SELECTs from the same vector into a single one.
+ Restrict the transformation to avoid generating a VEC_SELECT with a
+ mode unrelated to its operand. */
if (GET_CODE (trueop0) == VEC_SELECT
&& GET_CODE (trueop1) == VEC_SELECT
- && rtx_equal_p (XEXP (trueop0, 0), XEXP (trueop1, 0)))
+ && rtx_equal_p (XEXP (trueop0, 0), XEXP (trueop1, 0))
+ && GET_MODE (XEXP (trueop0, 0)) == mode)
{
rtx par0 = XEXP (trueop0, 1);
rtx par1 = XEXP (trueop1, 1);
if (VECTOR_MODE_P (mode)
&& code == VEC_CONCAT
- && (CONST_INT_P (op0)
+ && (CONST_SCALAR_INT_P (op0)
|| GET_CODE (op0) == CONST_FIXED
- || CONST_DOUBLE_P (op0))
- && (CONST_INT_P (op1)
- || CONST_DOUBLE_P (op1)
+ || CONST_DOUBLE_AS_FLOAT_P (op0))
+ && (CONST_SCALAR_INT_P (op1)
+ || CONST_DOUBLE_AS_FLOAT_P (op1)
|| GET_CODE (op1) == CONST_FIXED))
{
unsigned n_elts = GET_MODE_NUNITS (mode);
switch (code)
{
case PLUS:
- val = arg0s + arg1s;
+ val = (unsigned HOST_WIDE_INT) arg0s + arg1s;
break;
case MINUS:
- val = arg0s - arg1s;
+ val = (unsigned HOST_WIDE_INT) arg0s - arg1s;
break;
case MULT:
- val = arg0s * arg1s;
+ val = (unsigned HOST_WIDE_INT) arg0s * arg1s;
break;
case DIV:
/* Sign-extend the result for arithmetic right shifts. */
if (code == ASHIFTRT && arg0s < 0 && arg1 > 0)
- val |= ((unsigned HOST_WIDE_INT) (-1)) << (width - arg1);
+ val |= HOST_WIDE_INT_M1U << (width - arg1);
break;
case ROTATERT:
&& GET_CODE (op0) == PLUS
&& CONST_INT_P (XEXP (op0, 1))
&& (rtx_equal_p (op1, XEXP (op0, 0))
- || rtx_equal_p (op1, XEXP (op0, 1))))
+ || rtx_equal_p (op1, XEXP (op0, 1)))
+ /* (LTU/GEU (PLUS a 0) 0) is not the same as (GEU/LTU a 0). */
+ && XEXP (op0, 1) != const0_rtx)
{
rtx new_cmp
= simplify_gen_unary (NEG, cmp_mode, XEXP (op0, 1), cmp_mode);
/* (eq/ne (xor x C1) C2) simplifies to (eq/ne x (C1^C2)). */
if ((code == EQ || code == NE)
&& op0code == XOR
- && (CONST_INT_P (op1) || CONST_DOUBLE_AS_INT_P (op1))
- && (CONST_INT_P (XEXP (op0, 1))
- || CONST_DOUBLE_AS_INT_P (XEXP (op0, 1))))
+ && CONST_SCALAR_INT_P (op1)
+ && CONST_SCALAR_INT_P (XEXP (op0, 1)))
return simplify_gen_relational (code, mode, cmp_mode, XEXP (op0, 0),
simplify_gen_binary (XOR, cmp_mode,
XEXP (op0, 1), op1));
+ /* (eq/ne (bswap x) C1) simplifies to (eq/ne x C2) with C2 swapped. */
+ if ((code == EQ || code == NE)
+ && GET_CODE (op0) == BSWAP
+ && CONST_SCALAR_INT_P (op1))
+ return simplify_gen_relational (code, mode, cmp_mode, XEXP (op0, 0),
+ simplify_gen_unary (BSWAP, cmp_mode,
+ op1, cmp_mode));
+
+ /* (eq/ne (bswap x) (bswap y)) simplifies to (eq/ne x y). */
+ if ((code == EQ || code == NE)
+ && GET_CODE (op0) == BSWAP
+ && GET_CODE (op1) == BSWAP)
+ return simplify_gen_relational (code, mode, cmp_mode,
+ XEXP (op0, 0), XEXP (op1, 0));
+
if (op0code == POPCOUNT && op1 == const0_rtx)
switch (code)
{
{
unsigned int width = GET_MODE_PRECISION (mode);
bool any_change = false;
- rtx tem;
+ rtx tem, trueop2;
/* VOIDmode means "infinite" precision. */
if (width == 0)
gcc_assert (GET_MODE (op0) == mode);
gcc_assert (GET_MODE (op1) == mode);
gcc_assert (VECTOR_MODE_P (mode));
- op2 = avoid_constant_pool_reference (op2);
- if (CONST_INT_P (op2))
+ trueop2 = avoid_constant_pool_reference (op2);
+ if (CONST_INT_P (trueop2))
{
- int elt_size = GET_MODE_SIZE (GET_MODE_INNER (mode));
+ int elt_size = GET_MODE_SIZE (GET_MODE_INNER (mode));
unsigned n_elts = (GET_MODE_SIZE (mode) / elt_size);
- int mask = (1 << n_elts) - 1;
+ unsigned HOST_WIDE_INT sel = UINTVAL (trueop2);
+ unsigned HOST_WIDE_INT mask;
+ if (n_elts == HOST_BITS_PER_WIDE_INT)
+ mask = -1;
+ else
+ mask = ((unsigned HOST_WIDE_INT) 1 << n_elts) - 1;
- if (!(INTVAL (op2) & mask))
+ if (!(sel & mask) && !side_effects_p (op0))
return op1;
- if ((INTVAL (op2) & mask) == mask)
+ if ((sel & mask) == mask && !side_effects_p (op1))
return op0;
- op0 = avoid_constant_pool_reference (op0);
- op1 = avoid_constant_pool_reference (op1);
- if (GET_CODE (op0) == CONST_VECTOR
- && GET_CODE (op1) == CONST_VECTOR)
+ rtx trueop0 = avoid_constant_pool_reference (op0);
+ rtx trueop1 = avoid_constant_pool_reference (op1);
+ if (GET_CODE (trueop0) == CONST_VECTOR
+ && GET_CODE (trueop1) == CONST_VECTOR)
{
rtvec v = rtvec_alloc (n_elts);
unsigned int i;
for (i = 0; i < n_elts; i++)
- RTVEC_ELT (v, i) = (INTVAL (op2) & (1 << i)
- ? CONST_VECTOR_ELT (op0, i)
- : CONST_VECTOR_ELT (op1, i));
+ RTVEC_ELT (v, i) = ((sel & ((unsigned HOST_WIDE_INT) 1 << i))
+ ? CONST_VECTOR_ELT (trueop0, i)
+ : CONST_VECTOR_ELT (trueop1, i));
return gen_rtx_CONST_VECTOR (mode, v);
}
+
+ /* Replace (vec_merge (vec_merge a b m) c n) with (vec_merge b c n)
+ if no element from a appears in the result. */
+ if (GET_CODE (op0) == VEC_MERGE)
+ {
+ tem = avoid_constant_pool_reference (XEXP (op0, 2));
+ if (CONST_INT_P (tem))
+ {
+ unsigned HOST_WIDE_INT sel0 = UINTVAL (tem);
+ if (!(sel & sel0 & mask) && !side_effects_p (XEXP (op0, 0)))
+ return simplify_gen_ternary (code, mode, mode,
+ XEXP (op0, 1), op1, op2);
+ if (!(sel & ~sel0 & mask) && !side_effects_p (XEXP (op0, 1)))
+ return simplify_gen_ternary (code, mode, mode,
+ XEXP (op0, 0), op1, op2);
+ }
+ }
+ if (GET_CODE (op1) == VEC_MERGE)
+ {
+ tem = avoid_constant_pool_reference (XEXP (op1, 2));
+ if (CONST_INT_P (tem))
+ {
+ unsigned HOST_WIDE_INT sel1 = UINTVAL (tem);
+ if (!(~sel & sel1 & mask) && !side_effects_p (XEXP (op1, 0)))
+ return simplify_gen_ternary (code, mode, mode,
+ op0, XEXP (op1, 1), op2);
+ if (!(~sel & ~sel1 & mask) && !side_effects_p (XEXP (op1, 1)))
+ return simplify_gen_ternary (code, mode, mode,
+ op0, XEXP (op1, 0), op2);
+ }
+ }
}
+
+ if (rtx_equal_p (op0, op1)
+ && !side_effects_p (op2) && !side_effects_p (op1))
+ return op0;
+
break;
default:
gcc_assert (GET_MODE (op) == innermode
|| GET_MODE (op) == VOIDmode);
- gcc_assert ((byte % GET_MODE_SIZE (outermode)) == 0);
- gcc_assert (byte < GET_MODE_SIZE (innermode));
+ if ((byte % GET_MODE_SIZE (outermode)) != 0)
+ return NULL_RTX;
+
+ if (byte >= GET_MODE_SIZE (innermode))
+ return NULL_RTX;
if (outermode == innermode && !byte)
return op;
- if (CONST_INT_P (op)
- || CONST_DOUBLE_P (op)
+ if (CONST_SCALAR_INT_P (op)
+ || CONST_DOUBLE_AS_FLOAT_P (op)
|| GET_CODE (op) == CONST_FIXED
|| GET_CODE (op) == CONST_VECTOR)
return simplify_immed_subreg (outermode, op, innermode, byte);
return NULL_RTX;
}
- /* Merge implicit and explicit truncations. */
-
- if (GET_CODE (op) == TRUNCATE
- && GET_MODE_SIZE (outermode) < GET_MODE_SIZE (innermode)
- && subreg_lowpart_offset (outermode, innermode) == byte)
- return simplify_gen_unary (TRUNCATE, outermode, XEXP (op, 0),
- GET_MODE (XEXP (op, 0)));
-
/* SUBREG of a hard register => just change the register number
and/or mode. If the hard register is not valid in that mode,
suppress this simplification. If the hard register is the stack,
return NULL_RTX;
}
- /* Optimize SUBREG truncations of zero and sign extended values. */
- if ((GET_CODE (op) == ZERO_EXTEND
- || GET_CODE (op) == SIGN_EXTEND)
- && SCALAR_INT_MODE_P (innermode)
- && GET_MODE_PRECISION (outermode) < GET_MODE_PRECISION (innermode))
+ /* 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 && SCALAR_INT_MODE_P (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_PRECISION (outermode) <= GET_MODE_PRECISION (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_PRECISION (GET_MODE (XEXP (op, 0))))
+ if (bitpos >= GET_MODE_PRECISION (GET_MODE (XEXP (op, 0))))
return CONST0_RTX (outermode);
}
- /* Simplify (subreg:SI (op:DI ((x:DI) (y:DI)), 0)
- to (op:SI (subreg:SI (x:DI) 0) (subreg:SI (x:DI) 0)), where
- the outer subreg is effectively a truncation to the original mode. */
- if ((GET_CODE (op) == PLUS
- || GET_CODE (op) == MINUS
- || GET_CODE (op) == MULT)
- && SCALAR_INT_MODE_P (outermode)
- && SCALAR_INT_MODE_P (innermode)
- && GET_MODE_PRECISION (outermode) < GET_MODE_PRECISION (innermode)
- && byte == subreg_lowpart_offset (outermode, innermode))
- {
- rtx op0 = simplify_gen_subreg (outermode, XEXP (op, 0),
- innermode, byte);
- if (op0)
- {
- rtx op1 = simplify_gen_subreg (outermode, XEXP (op, 1),
- innermode, byte);
- if (op1)
- return simplify_gen_binary (GET_CODE (op), outermode, op0, op1);
- }
- }
-
- /* Simplify (subreg:QI (lshiftrt:SI (sign_extend:SI (x:QI)) C), 0) into
- to (ashiftrt:QI (x:QI) C), where C is a suitable small constant and
- the outer subreg is effectively a truncation to the original mode. */
- if ((GET_CODE (op) == LSHIFTRT
- || GET_CODE (op) == ASHIFTRT)
- && SCALAR_INT_MODE_P (outermode)
- && SCALAR_INT_MODE_P (innermode)
- /* Ensure that OUTERMODE is at least twice as wide as the INNERMODE
- to avoid the possibility that an outer LSHIFTRT shifts by more
- than the sign extension's sign_bit_copies and introduces zeros
- into the high bits of the result. */
- && (2 * GET_MODE_PRECISION (outermode)) <= GET_MODE_PRECISION (innermode)
- && CONST_INT_P (XEXP (op, 1))
- && GET_CODE (XEXP (op, 0)) == SIGN_EXTEND
- && GET_MODE (XEXP (XEXP (op, 0), 0)) == outermode
- && INTVAL (XEXP (op, 1)) < GET_MODE_PRECISION (outermode)
- && subreg_lsb_1 (outermode, innermode, byte) == 0)
- return simplify_gen_binary (ASHIFTRT, outermode,
- XEXP (XEXP (op, 0), 0), XEXP (op, 1));
-
- /* Likewise (subreg:QI (lshiftrt:SI (zero_extend:SI (x:QI)) C), 0) into
- to (lshiftrt:QI (x:QI) C), where C is a suitable small constant and
- the outer subreg is effectively a truncation to the original mode. */
- if ((GET_CODE (op) == LSHIFTRT
- || GET_CODE (op) == ASHIFTRT)
- && SCALAR_INT_MODE_P (outermode)
- && SCALAR_INT_MODE_P (innermode)
- && GET_MODE_PRECISION (outermode) < GET_MODE_PRECISION (innermode)
- && CONST_INT_P (XEXP (op, 1))
- && GET_CODE (XEXP (op, 0)) == ZERO_EXTEND
- && GET_MODE (XEXP (XEXP (op, 0), 0)) == outermode
- && INTVAL (XEXP (op, 1)) < GET_MODE_PRECISION (outermode)
- && subreg_lsb_1 (outermode, innermode, byte) == 0)
- return simplify_gen_binary (LSHIFTRT, outermode,
- XEXP (XEXP (op, 0), 0), XEXP (op, 1));
-
- /* Likewise (subreg:QI (ashift:SI (zero_extend:SI (x:QI)) C), 0) into
- to (ashift:QI (x:QI) C), where C is a suitable small constant and
- the outer subreg is effectively a truncation to the original mode. */
- if (GET_CODE (op) == ASHIFT
- && SCALAR_INT_MODE_P (outermode)
+ if (SCALAR_INT_MODE_P (outermode)
&& SCALAR_INT_MODE_P (innermode)
&& GET_MODE_PRECISION (outermode) < GET_MODE_PRECISION (innermode)
- && CONST_INT_P (XEXP (op, 1))
- && (GET_CODE (XEXP (op, 0)) == ZERO_EXTEND
- || GET_CODE (XEXP (op, 0)) == SIGN_EXTEND)
- && GET_MODE (XEXP (XEXP (op, 0), 0)) == outermode
- && INTVAL (XEXP (op, 1)) < GET_MODE_PRECISION (outermode)
- && subreg_lsb_1 (outermode, innermode, byte) == 0)
- return simplify_gen_binary (ASHIFT, outermode,
- XEXP (XEXP (op, 0), 0), XEXP (op, 1));
-
- /* Recognize a word extraction from a multi-word subreg. */
- if ((GET_CODE (op) == LSHIFTRT
- || GET_CODE (op) == ASHIFTRT)
- && SCALAR_INT_MODE_P (innermode)
- && GET_MODE_PRECISION (outermode) >= BITS_PER_WORD
- && GET_MODE_PRECISION (innermode) >= (2 * GET_MODE_PRECISION (outermode))
- && CONST_INT_P (XEXP (op, 1))
- && (INTVAL (XEXP (op, 1)) & (GET_MODE_PRECISION (outermode) - 1)) == 0
- && INTVAL (XEXP (op, 1)) >= 0
- && INTVAL (XEXP (op, 1)) < GET_MODE_PRECISION (innermode)
&& byte == subreg_lowpart_offset (outermode, innermode))
{
- int shifted_bytes = INTVAL (XEXP (op, 1)) / BITS_PER_UNIT;
- return simplify_gen_subreg (outermode, XEXP (op, 0), innermode,
- (WORDS_BIG_ENDIAN
- ? byte - shifted_bytes
- : byte + shifted_bytes));
- }
-
- /* If we have a lowpart SUBREG of a right shift of MEM, make a new MEM
- and try replacing the SUBREG and shift with it. Don't do this if
- the MEM has a mode-dependent address or if we would be widening it. */
-
- if ((GET_CODE (op) == LSHIFTRT
- || GET_CODE (op) == ASHIFTRT)
- && SCALAR_INT_MODE_P (innermode)
- && MEM_P (XEXP (op, 0))
- && CONST_INT_P (XEXP (op, 1))
- && GET_MODE_SIZE (outermode) < GET_MODE_SIZE (GET_MODE (op))
- && (INTVAL (XEXP (op, 1)) % GET_MODE_BITSIZE (outermode)) == 0
- && INTVAL (XEXP (op, 1)) > 0
- && INTVAL (XEXP (op, 1)) < GET_MODE_BITSIZE (innermode)
- && ! mode_dependent_address_p (XEXP (XEXP (op, 0), 0),
- MEM_ADDR_SPACE (XEXP (op, 0)))
- && ! MEM_VOLATILE_P (XEXP (op, 0))
- && byte == subreg_lowpart_offset (outermode, innermode)
- && (GET_MODE_SIZE (outermode) >= UNITS_PER_WORD
- || WORDS_BIG_ENDIAN == BYTES_BIG_ENDIAN))
- {
- int shifted_bytes = INTVAL (XEXP (op, 1)) / BITS_PER_UNIT;
- return adjust_address_nv (XEXP (op, 0), outermode,
- (WORDS_BIG_ENDIAN
- ? byte - shifted_bytes
- : byte + shifted_bytes));
+ rtx tem = simplify_truncation (outermode, op, innermode);
+ if (tem)
+ return tem;
}
return NULL_RTX;