static void undo_all PROTO((void));
static rtx *find_split_point PROTO((rtx *, rtx));
static rtx subst PROTO((rtx, rtx, rtx, int, int));
+static rtx simplify_rtx PROTO((rtx, enum machine_mode, int, int));
+static rtx simplify_if_then_else PROTO((rtx));
+static rtx simplify_set PROTO((rtx));
+static rtx simplify_logical PROTO((rtx, int));
static rtx expand_compound_operation PROTO((rtx));
static rtx expand_field_assignment PROTO((rtx));
static rtx make_extraction PROTO((enum machine_mode, rtx, int, rtx, int,
int in_dest;
int unique_copy;
{
- register char *fmt;
- register int len, i;
register enum rtx_code code = GET_CODE (x), orig_code = code;
- rtx temp;
- enum machine_mode mode = GET_MODE (x);
enum machine_mode op0_mode = VOIDmode;
- rtx other_insn;
- rtx *cc_use;
- int n_restarts = 0;
-
-/* FAKE_EXTEND_SAFE_P (MODE, FROM) is 1 if (subreg:MODE FROM 0) is a safe
- replacement for (zero_extend:MODE FROM) or (sign_extend:MODE FROM).
- If it is 0, that cannot be done. We can now do this for any MEM
- because (SUBREG (MEM...)) is guaranteed to cause the MEM to be reloaded.
- If not for that, MEM's would very rarely be safe. */
-
-/* Reject MODEs bigger than a word, because we might not be able
- to reference a two-register group starting with an arbitrary register
- (and currently gen_lowpart might crash for a SUBREG). */
-
-#define FAKE_EXTEND_SAFE_P(MODE, FROM) \
- (GET_MODE_SIZE (MODE) <= UNITS_PER_WORD)
+ register char *fmt;
+ register int len, i;
+ rtx new;
/* Two expressions are equal if they are identical copies of a shared
RTX or if they are both registers with the same register number
register int j;
for (j = XVECLEN (x, i) - 1; j >= 0; j--)
{
- register rtx new;
if (COMBINE_RTX_EQUAL_P (XVECEXP (x, i, j), from))
{
new = (unique_copy && n_occurrences ? copy_rtx (to) : to);
}
else if (fmt[i] == 'e')
{
- register rtx new;
-
if (COMBINE_RTX_EQUAL_P (XEXP (x, i), from))
{
/* In general, don't install a subreg involving two modes not
&& ! MODES_TIEABLE_P (GET_MODE (to),
GET_MODE (SUBREG_REG (to)))
&& ! (code == SUBREG
- && MODES_TIEABLE_P (mode, GET_MODE (SUBREG_REG (to))))
+ && MODES_TIEABLE_P (GET_MODE (x),
+ GET_MODE (SUBREG_REG (to))))
#ifdef HAVE_cc0
&& ! (code == SET && i == 1 && XEXP (x, 0) == cc0_rtx)
#endif
}
}
- /* We come back to here if we have replaced the expression with one of
- a different code and it is likely that further simplification will be
- possible. */
+ /* Try to simplify X. If the simplification changed the code, it is likely
+ that further simplification will help, so loop, but limit the number
+ of repetitions that will be performed. */
+
+ for (i = 0; i < 4; i++)
+ {
+ /* If X is sufficiently simple, don't bother trying to do anything
+ with it. */
+ if (code != CONST_INT && code != REG && code != CLOBBER)
+ x = simplify_rtx (x, op0_mode, i == 3, in_dest);
- restart:
+ if (GET_CODE (x) == code)
+ break;
- /* If we have restarted more than 4 times, we are probably looping, so
- give up. */
- if (++n_restarts > 4)
- return x;
+ code = GET_CODE (x);
- /* If we are restarting at all, it means that we no longer know the
- original mode of operand 0 (since we have probably changed the
- form of X). */
+ /* We no longer know the original mode of operand 0 since we
+ have changed the form of X) */
+ op0_mode = VOIDmode;
+ }
- if (n_restarts > 1)
- op0_mode = VOIDmode;
+ return x;
+}
+\f
+/* Simplify X, a piece of RTL. We just operate on the expression at the
+ outer level; call `subst' to simplify recursively. Return the new
+ expression.
- code = GET_CODE (x);
+ OP0_MODE is the original mode of XEXP (x, 0); LAST is nonzero if this
+ will be the iteration even if an expression with a code different from
+ X is returned; IN_DEST is nonzero if we are inside a SET_DEST. */
+
+static rtx
+simplify_rtx (x, op0_mode, last, in_dest)
+ rtx x;
+ enum machine_mode op0_mode;
+ int last;
+ int in_dest;
+{
+ enum rtx_code code = GET_CODE (x);
+ enum machine_mode mode = GET_MODE (x);
+ rtx temp;
+ int i;
/* If this is a commutative operation, put a constant last and a complex
expression first. We don't need to do this for comparisons here. */
gen_binary (reverse_condition (cond_code),
mode, cond, cop1));
else
- {
- x = gen_rtx (IF_THEN_ELSE, mode,
- gen_binary (cond_code, VOIDmode, cond, cop1),
- true, false);
- goto restart;
- }
+ return gen_rtx (IF_THEN_ELSE, mode,
+ gen_binary (cond_code, VOIDmode, cond, cop1),
+ true, false);
code = GET_CODE (x);
op0_mode = VOIDmode;
}
if (inner)
- {
- x = gen_binary (code, mode, other, inner);
- goto restart;
-
- }
+ return gen_binary (code, mode, other, inner);
}
}
/* (not (plus X -1)) can become (neg X). */
if (GET_CODE (XEXP (x, 0)) == PLUS
&& XEXP (XEXP (x, 0), 1) == constm1_rtx)
- {
- x = gen_rtx_combine (NEG, mode, XEXP (XEXP (x, 0), 0));
- goto restart;
- }
+ return gen_rtx_combine (NEG, mode, XEXP (XEXP (x, 0), 0));
/* Similarly, (not (neg X)) is (plus X -1). */
if (GET_CODE (XEXP (x, 0)) == NEG)
- {
- x = gen_rtx_combine (PLUS, mode, XEXP (XEXP (x, 0), 0), constm1_rtx);
- goto restart;
- }
+ return gen_rtx_combine (PLUS, mode, XEXP (XEXP (x, 0), 0),
+ constm1_rtx);
/* (not (xor X C)) for C constant is (xor X D) with D = ~ C. */
if (GET_CODE (XEXP (x, 0)) == XOR
but this doesn't seem common enough to bother with. */
if (GET_CODE (XEXP (x, 0)) == ASHIFT
&& XEXP (XEXP (x, 0), 0) == const1_rtx)
- {
- x = gen_rtx (ROTATE, mode, gen_unary (NOT, mode, const1_rtx),
- XEXP (XEXP (x, 0), 1));
- goto restart;
- }
+ return gen_rtx (ROTATE, mode, gen_unary (NOT, mode, const1_rtx),
+ XEXP (XEXP (x, 0), 1));
if (GET_CODE (XEXP (x, 0)) == SUBREG
&& subreg_lowpart_p (XEXP (x, 0))
x = gen_rtx (ROTATE, inner_mode,
gen_unary (NOT, inner_mode, const1_rtx),
XEXP (SUBREG_REG (XEXP (x, 0)), 1));
- x = gen_lowpart_for_combine (mode, x);
- goto restart;
+ return gen_lowpart_for_combine (mode, x);
}
#if STORE_FLAG_VALUE == -1
in2 = in1; in1 = tem;
}
- x = gen_rtx_combine (GET_CODE (XEXP (x, 0)) == IOR ? AND : IOR,
- mode, in1, in2);
- goto restart;
+ return gen_rtx_combine (GET_CODE (XEXP (x, 0)) == IOR ? AND : IOR,
+ mode, in1, in2);
}
break;
/* (neg (plus X 1)) can become (not X). */
if (GET_CODE (XEXP (x, 0)) == PLUS
&& XEXP (XEXP (x, 0), 1) == const1_rtx)
- {
- x = gen_rtx_combine (NOT, mode, XEXP (XEXP (x, 0), 0));
- goto restart;
- }
+ return gen_rtx_combine (NOT, mode, XEXP (XEXP (x, 0), 0));
/* Similarly, (neg (not X)) is (plus X 1). */
if (GET_CODE (XEXP (x, 0)) == NOT)
- {
- x = plus_constant (XEXP (XEXP (x, 0), 0), 1);
- goto restart;
- }
+ return plus_constant (XEXP (XEXP (x, 0), 0), 1);
/* (neg (minus X Y)) can become (minus Y X). */
if (GET_CODE (XEXP (x, 0)) == MINUS
/* x-y != -(y-x) with IEEE floating point. */
|| TARGET_FLOAT_FORMAT != IEEE_FLOAT_FORMAT
|| flag_fast_math))
- {
- x = gen_binary (MINUS, mode, XEXP (XEXP (x, 0), 1),
- XEXP (XEXP (x, 0), 0));
- goto restart;
- }
+ return gen_binary (MINUS, mode, XEXP (XEXP (x, 0), 1),
+ XEXP (XEXP (x, 0), 0));
/* (neg (xor A 1)) is (plus A -1) if A is known to be either 0 or 1. */
if (GET_CODE (XEXP (x, 0)) == XOR && XEXP (XEXP (x, 0), 1) == const1_rtx
&& nonzero_bits (XEXP (XEXP (x, 0), 0), mode) == 1)
- {
- x = gen_binary (PLUS, mode, XEXP (XEXP (x, 0), 0), constm1_rtx);
- goto restart;
- }
+ return gen_binary (PLUS, mode, XEXP (XEXP (x, 0), 0), constm1_rtx);
/* NEG commutes with ASHIFT since it is multiplication. Only do this
if we can then eliminate the NEG (e.g.,
if (GET_CODE (temp) == ASHIFTRT
&& GET_CODE (XEXP (temp, 1)) == CONST_INT
&& INTVAL (XEXP (temp, 1)) == GET_MODE_BITSIZE (mode) - 1)
- {
- x = simplify_shift_const (temp, LSHIFTRT, mode, XEXP (temp, 0),
- INTVAL (XEXP (temp, 1)));
- goto restart;
- }
+ return simplify_shift_const (temp, LSHIFTRT, mode, XEXP (temp, 0),
+ INTVAL (XEXP (temp, 1)));
/* If X has only a single bit that might be nonzero, say, bit I, convert
(neg X) to (ashiftrt (ashift X C-I) C-I) where C is the bitsize of
if (GET_CODE (temp1) != ASHIFTRT
|| GET_CODE (XEXP (temp1, 0)) != ASHIFT
|| XEXP (XEXP (temp1, 0), 0) != temp)
- {
- x = temp1;
- goto restart;
- }
+ return temp1;
}
break;
|| (GET_CODE (XEXP (XEXP (x, 0), 0)) == ZERO_EXTEND
&& (GET_MODE_BITSIZE (GET_MODE (XEXP (XEXP (XEXP (x, 0), 0), 0)))
== i + 1))))
- {
- x = simplify_shift_const
- (NULL_RTX, ASHIFTRT, mode,
- simplify_shift_const (NULL_RTX, ASHIFT, mode,
- XEXP (XEXP (XEXP (x, 0), 0), 0),
- GET_MODE_BITSIZE (mode) - (i + 1)),
- GET_MODE_BITSIZE (mode) - (i + 1));
- goto restart;
- }
+ return simplify_shift_const
+ (NULL_RTX, ASHIFTRT, mode,
+ simplify_shift_const (NULL_RTX, ASHIFT, mode,
+ XEXP (XEXP (XEXP (x, 0), 0), 0),
+ GET_MODE_BITSIZE (mode) - (i + 1)),
+ GET_MODE_BITSIZE (mode) - (i + 1));
/* (plus (comparison A B) C) can become (neg (rev-comp A B)) if
C is 1 and STORE_FLAG_VALUE is -1 or if C is -1 and STORE_FLAG_VALUE
&& reversible_comparison_p (XEXP (x, 0))
&& ((STORE_FLAG_VALUE == -1 && XEXP (x, 1) == const1_rtx)
|| (STORE_FLAG_VALUE == 1 && XEXP (x, 1) == constm1_rtx)))
- {
- x = gen_binary (reverse_condition (GET_CODE (XEXP (x, 0))),
- mode, XEXP (XEXP (x, 0), 0), XEXP (XEXP (x, 0), 1));
- x = gen_unary (NEG, mode, x);
- goto restart;
- }
+ return
+ gen_unary (NEG, mode,
+ gen_binary (reverse_condition (GET_CODE (XEXP (x, 0))),
+ mode, XEXP (XEXP (x, 0), 0),
+ XEXP (XEXP (x, 0), 1)));
/* If only the low-order bit of X is possibly nonzero, (plus x -1)
can become (ashiftrt (ashift (xor x 1) C) C) where C is
&& ! (GET_CODE (XEXP (x,0)) == SUBREG
&& GET_CODE (SUBREG_REG (XEXP (x, 0))) == REG)
&& nonzero_bits (XEXP (x, 0), mode) == 1)
- {
- x = simplify_shift_const
- (NULL_RTX, ASHIFTRT, mode,
- simplify_shift_const (NULL_RTX, ASHIFT, mode,
- gen_rtx_combine (XOR, mode,
- XEXP (x, 0), const1_rtx),
- GET_MODE_BITSIZE (mode) - 1),
- GET_MODE_BITSIZE (mode) - 1);
- goto restart;
- }
+ return simplify_shift_const (NULL_RTX, ASHIFTRT, mode,
+ simplify_shift_const (NULL_RTX, ASHIFT, mode,
+ gen_rtx_combine (XOR, mode,
+ XEXP (x, 0), const1_rtx),
+ GET_MODE_BITSIZE (mode) - 1),
+ GET_MODE_BITSIZE (mode) - 1);
/* If we are adding two things that have no bits in common, convert
the addition into an IOR. This will often be further simplified,
if (GET_MODE_BITSIZE (mode) <= HOST_BITS_PER_WIDE_INT
&& (nonzero_bits (XEXP (x, 0), mode)
& nonzero_bits (XEXP (x, 1), mode)) == 0)
- {
- x = gen_binary (IOR, mode, XEXP (x, 0), XEXP (x, 1));
- goto restart;
- }
+ return gen_binary (IOR, mode, XEXP (x, 0), XEXP (x, 1));
break;
case MINUS:
&& GET_CODE (XEXP (XEXP (x, 1), 1)) == CONST_INT
&& exact_log2 (- INTVAL (XEXP (XEXP (x, 1), 1))) >= 0
&& rtx_equal_p (XEXP (XEXP (x, 1), 0), XEXP (x, 0)))
- {
- x = simplify_and_const_int (NULL_RTX, mode, XEXP (x, 0),
- - INTVAL (XEXP (XEXP (x, 1), 1)) - 1);
- goto restart;
- }
+ return simplify_and_const_int (NULL_RTX, mode, XEXP (x, 0),
+ - INTVAL (XEXP (XEXP (x, 1), 1)) - 1);
/* Canonicalize (minus A (plus B C)) to (minus (minus A B) C) for
integers. */
if (GET_CODE (XEXP (x, 1)) == PLUS && INTEGRAL_MODE_P (mode))
- {
- x = gen_binary (MINUS, mode,
- gen_binary (MINUS, mode, XEXP (x, 0),
- XEXP (XEXP (x, 1), 0)),
- XEXP (XEXP (x, 1), 1));
- goto restart;
- }
+ return gen_binary (MINUS, mode,
+ gen_binary (MINUS, mode, XEXP (x, 0),
+ XEXP (XEXP (x, 1), 0)),
+ XEXP (XEXP (x, 1), 1));
break;
case MULT:
XEXP (XEXP (x, 0), 1), XEXP (x, 1))));
if (GET_CODE (x) != MULT)
- goto restart;
+ return x;
}
/* If this is multiplication by a power of two and its first operand is
|| GET_CODE (XEXP (x, 0)) == ASHIFTRT
|| GET_CODE (XEXP (x, 0)) == ROTATE
|| GET_CODE (XEXP (x, 0)) == ROTATERT))
- {
- x = simplify_shift_const (NULL_RTX, ASHIFT, mode, XEXP (x, 0), i);
- goto restart;
- }
+ return simplify_shift_const (NULL_RTX, ASHIFT, mode, XEXP (x, 0), i);
/* Convert (mult (ashift (const_int 1) A) B) to (ashift B A). */
if (GET_CODE (XEXP (x, 0)) == ASHIFT
|| GET_CODE (XEXP (x, 0)) == ASHIFTRT
|| GET_CODE (XEXP (x, 0)) == ROTATE
|| GET_CODE (XEXP (x, 0)) == ROTATERT))
- {
- x = simplify_shift_const (NULL_RTX, LSHIFTRT, mode, XEXP (x, 0), i);
- goto restart;
- }
+ return simplify_shift_const (NULL_RTX, LSHIFTRT, mode, XEXP (x, 0), i);
break;
case EQ: case NE:
== GET_MODE_BITSIZE (mode)))
{
op0 = expand_compound_operation (op0);
- x = gen_unary (NEG, mode, gen_lowpart_for_combine (mode, op0));
- goto restart;
+ return gen_unary (NEG, mode,
+ gen_lowpart_for_combine (mode, op0));
}
else if (new_code == EQ && GET_MODE_CLASS (mode) == MODE_INT
&& nonzero_bits (op0, mode) == 1)
{
op0 = expand_compound_operation (op0);
- x = gen_binary (XOR, mode,
- gen_lowpart_for_combine (mode, op0),
- const1_rtx);
- goto restart;
+ return gen_binary (XOR, mode,
+ gen_lowpart_for_combine (mode, op0),
+ const1_rtx);
}
else if (new_code == EQ && GET_MODE_CLASS (mode) == MODE_INT
== GET_MODE_BITSIZE (mode)))
{
op0 = expand_compound_operation (op0);
- x = plus_constant (gen_lowpart_for_combine (mode, op0), 1);
- goto restart;
+ return plus_constant (gen_lowpart_for_combine (mode, op0), 1);
}
#endif
&& nonzero_bits (op0, mode) == 1)
{
op0 = expand_compound_operation (op0);
- x = gen_unary (NEG, mode, gen_lowpart_for_combine (mode, op0));
- goto restart;
+ return gen_unary (NEG, mode,
+ gen_lowpart_for_combine (mode, op0));
}
else if (new_code == EQ && GET_MODE_CLASS (mode) == MODE_INT
== GET_MODE_BITSIZE (mode)))
{
op0 = expand_compound_operation (op0);
- x = gen_unary (NOT, mode, gen_lowpart_for_combine (mode, op0));
- goto restart;
+ return gen_unary (NOT, mode,
+ gen_lowpart_for_combine (mode, op0));
}
/* If X is 0/1, (eq X 0) is X-1. */
&& nonzero_bits (op0, mode) == 1)
{
op0 = expand_compound_operation (op0);
- x = plus_constant (gen_lowpart_for_combine (mode, op0), -1);
- goto restart;
+ return plus_constant (gen_lowpart_for_combine (mode, op0), -1);
}
#endif
break;
case IF_THEN_ELSE:
- /* Simplify storing of the truth value. */
- if (GET_RTX_CLASS (GET_CODE (XEXP (x, 0))) == '<'
- && XEXP (x, 1) == const_true_rtx
- && XEXP (x, 2) == const0_rtx)
- return gen_binary (GET_CODE (XEXP (x, 0)), mode, XEXP (XEXP (x, 0), 0),
- XEXP (XEXP (x, 0), 1));
-
- /* Also when the truth value has to be reversed. */
- if (GET_RTX_CLASS (GET_CODE (XEXP (x, 0))) == '<'
- && reversible_comparison_p (XEXP (x, 0))
- && XEXP (x, 1) == const0_rtx
- && XEXP (x, 2) == const_true_rtx)
- return gen_binary (reverse_condition (GET_CODE (XEXP (x, 0))),
- mode, XEXP (XEXP (x, 0), 0), XEXP (XEXP (x, 0), 1));
+ return simplify_if_then_else (x);
+
+ case ZERO_EXTRACT:
+ case SIGN_EXTRACT:
+ case ZERO_EXTEND:
+ case SIGN_EXTEND:
+ /* If we are processing SET_DEST, we are done. */
+ if (in_dest)
+ return x;
- /* Sometimes we can simplify the arm of an IF_THEN_ELSE if a register
- used in it is being compared against certain values. Get the
- true and false comparisons and see if that says anything about the
- value of each arm. */
+ return expand_compound_operation (x);
- if (GET_RTX_CLASS (GET_CODE (XEXP (x, 0))) == '<'
- && reversible_comparison_p (XEXP (x, 0))
- && GET_CODE (XEXP (XEXP (x, 0), 0)) == REG)
- {
- HOST_WIDE_INT nzb;
- rtx from = XEXP (XEXP (x, 0), 0);
- enum rtx_code true_code = GET_CODE (XEXP (x, 0));
- enum rtx_code false_code = reverse_condition (true_code);
- rtx true_val = XEXP (XEXP (x, 0), 1);
- rtx false_val = true_val;
- rtx true_arm = XEXP (x, 1);
- rtx false_arm = XEXP (x, 2);
- int swapped = 0;
-
- /* If FALSE_CODE is EQ, swap the codes and arms. */
-
- if (false_code == EQ)
- {
- swapped = 1, true_code = EQ, false_code = NE;
- true_arm = XEXP (x, 2), false_arm = XEXP (x, 1);
- }
+ case SET:
+ return simplify_set (x);
- /* If we are comparing against zero and the expression being tested
- has only a single bit that might be nonzero, that is its value
- when it is not equal to zero. Similarly if it is known to be
- -1 or 0. */
-
- if (true_code == EQ && true_val == const0_rtx
- && exact_log2 (nzb = nonzero_bits (from, GET_MODE (from))) >= 0)
- false_code = EQ, false_val = GEN_INT (nzb);
- else if (true_code == EQ && true_val == const0_rtx
- && (num_sign_bit_copies (from, GET_MODE (from))
- == GET_MODE_BITSIZE (GET_MODE (from))))
- false_code = EQ, false_val = constm1_rtx;
-
- /* Now simplify an arm if we know the value of the register
- in the branch and it is used in the arm. Be carefull due to
- the potential of locally-shared RTL. */
-
- if (reg_mentioned_p (from, true_arm))
- true_arm = subst (known_cond (copy_rtx (true_arm), true_code,
- from, true_val),
- pc_rtx, pc_rtx, 0, 0);
- if (reg_mentioned_p (from, false_arm))
- false_arm = subst (known_cond (copy_rtx (false_arm), false_code,
- from, false_val),
- pc_rtx, pc_rtx, 0, 0);
-
- SUBST (XEXP (x, 1), swapped ? false_arm : true_arm);
- SUBST (XEXP (x, 2), swapped ? true_arm : false_arm);
- }
+ case AND:
+ case IOR:
+ case XOR:
+ return simplify_logical (x, last);
+
+ case ABS:
+ /* (abs (neg <foo>)) -> (abs <foo>) */
+ if (GET_CODE (XEXP (x, 0)) == NEG)
+ SUBST (XEXP (x, 0), XEXP (XEXP (x, 0), 0));
+
+ /* If operand is something known to be positive, ignore the ABS. */
+ if (GET_CODE (XEXP (x, 0)) == FFS || GET_CODE (XEXP (x, 0)) == ABS
+ || ((GET_MODE_BITSIZE (GET_MODE (XEXP (x, 0)))
+ <= HOST_BITS_PER_WIDE_INT)
+ && ((nonzero_bits (XEXP (x, 0), GET_MODE (XEXP (x, 0)))
+ & ((HOST_WIDE_INT) 1
+ << (GET_MODE_BITSIZE (GET_MODE (XEXP (x, 0))) - 1)))
+ == 0)))
+ return XEXP (x, 0);
+
+
+ /* If operand is known to be only -1 or 0, convert ABS to NEG. */
+ if (num_sign_bit_copies (XEXP (x, 0), mode) == GET_MODE_BITSIZE (mode))
+ return gen_rtx_combine (NEG, mode, XEXP (x, 0));
+
+ break;
+
+ case FFS:
+ /* (ffs (*_extend <X>)) = (ffs <X>) */
+ if (GET_CODE (XEXP (x, 0)) == SIGN_EXTEND
+ || GET_CODE (XEXP (x, 0)) == ZERO_EXTEND)
+ SUBST (XEXP (x, 0), XEXP (XEXP (x, 0), 0));
+ break;
+
+ case FLOAT:
+ /* (float (sign_extend <X>)) = (float <X>). */
+ if (GET_CODE (XEXP (x, 0)) == SIGN_EXTEND)
+ SUBST (XEXP (x, 0), XEXP (XEXP (x, 0), 0));
+ break;
+
+ case LSHIFT:
+ case ASHIFT:
+ case LSHIFTRT:
+ case ASHIFTRT:
+ case ROTATE:
+ case ROTATERT:
+ /* If this is a shift by a constant amount, simplify it. */
+ if (GET_CODE (XEXP (x, 1)) == CONST_INT)
+ return simplify_shift_const (x, code, mode, XEXP (x, 0),
+ INTVAL (XEXP (x, 1)));
+
+#ifdef SHIFT_COUNT_TRUNCATED
+ else if (SHIFT_COUNT_TRUNCATED && GET_CODE (XEXP (x, 1)) != REG)
+ SUBST (XEXP (x, 1),
+ force_to_mode (XEXP (x, 1), GET_MODE (x),
+ ((HOST_WIDE_INT) 1
+ << exact_log2 (GET_MODE_BITSIZE (GET_MODE (x))))
+ - 1,
+ NULL_RTX, 0));
+#endif
+
+ break;
+ }
+
+ return x;
+}
+\f
+/* Simplify X, an IF_THEN_ELSE expression. Return the new expression. */
+
+static rtx
+simplify_if_then_else (x)
+ rtx x;
+{
+ enum machine_mode mode = GET_MODE (x);
+ rtx cond = XEXP (x, 0);
+ rtx true = XEXP (x, 1);
+ rtx false = XEXP (x, 2);
+ enum rtx_code true_code = GET_CODE (cond);
+ int comparison_p = GET_RTX_CLASS (true_code) == '<';
+ rtx temp;
+ int i;
+
+ /* Simplify storing of the truth value. */
+ if (comparison_p && true == const_true_rtx && false == const0_rtx)
+ return gen_binary (true_code, mode, XEXP (cond, 0), XEXP (cond, 1));
- /* If we have (if_then_else FOO (pc) (label_ref BAR)) and FOO can be
- reversed, do so to avoid needing two sets of patterns for
- subtract-and-branch insns. Similarly if we have a constant in the
- true arm, the false arm is the same as the first operand of the
- comparison, or the false arm is more complicated than the true
- arm. */
+ /* Also when the truth value has to be reversed. */
+ if (comparison_p && reversible_comparison_p (cond)
+ && true == const0_rtx && false == const_true_rtx)
+ return gen_binary (reverse_condition (true_code),
+ mode, XEXP (cond, 0), XEXP (cond, 1));
+
+ /* Sometimes we can simplify the arm of an IF_THEN_ELSE if a register used
+ in it is being compared against certain values. Get the true and false
+ comparisons and see if that says anything about the value of each arm. */
+
+ if (comparison_p && reversible_comparison_p (cond)
+ && GET_CODE (XEXP (cond, 0)) == REG)
+ {
+ HOST_WIDE_INT nzb;
+ rtx from = XEXP (cond, 0);
+ enum rtx_code false_code = reverse_condition (true_code);
+ rtx true_val = XEXP (cond, 1);
+ rtx false_val = true_val;
+ int swapped = 0;
- if (GET_RTX_CLASS (GET_CODE (XEXP (x, 0))) == '<'
- && reversible_comparison_p (XEXP (x, 0))
- && (XEXP (x, 1) == pc_rtx
- || (CONSTANT_P (XEXP (x, 1))
- && GET_CODE (XEXP (x, 2)) != CONST_INT
- && XEXP (x, 2) != pc_rtx)
- || XEXP (x, 1) == const0_rtx
- || (GET_RTX_CLASS (GET_CODE (XEXP (x, 1))) == 'o'
- && GET_RTX_CLASS (GET_CODE (XEXP (x, 2))) != 'o')
- || (GET_CODE (XEXP (x, 1)) == SUBREG
- && GET_RTX_CLASS (GET_CODE (SUBREG_REG (XEXP (x, 1)))) == 'o'
- && GET_RTX_CLASS (GET_CODE (XEXP (x, 2))) != 'o')
- || reg_mentioned_p (XEXP (x, 1), XEXP (x, 2))
- || rtx_equal_p (XEXP (x, 2), XEXP (XEXP (x, 0), 0))))
- {
- SUBST (XEXP (x, 0),
- gen_binary (reverse_condition (GET_CODE (XEXP (x, 0))),
- GET_MODE (XEXP (x, 0)),
- XEXP (XEXP (x, 0), 0), XEXP (XEXP (x, 0), 1)));
+ /* If FALSE_CODE is EQ, swap the codes and arms. */
- temp = XEXP (x, 1);
- SUBST (XEXP (x, 1), XEXP (x, 2));
- SUBST (XEXP (x, 2), temp);
+ if (false_code == EQ)
+ {
+ swapped = 1, true_code = EQ, false_code = NE;
+ temp = true, true = false, false = temp;
}
- /* If the two arms are identical, we don't need the comparison. */
+ /* If we are comparing against zero and the expression being tested has
+ only a single bit that might be nonzero, that is its value when it is
+ not equal to zero. Similarly if it is known to be -1 or 0. */
- if (rtx_equal_p (XEXP (x, 1), XEXP (x, 2))
- && ! side_effects_p (XEXP (x, 0)))
- return XEXP (x, 1);
+ if (true_code == EQ && true_val == const0_rtx
+ && exact_log2 (nzb = nonzero_bits (from, GET_MODE (from))) >= 0)
+ false_code = EQ, false_val = GEN_INT (nzb);
+ else if (true_code == EQ && true_val == const0_rtx
+ && (num_sign_bit_copies (from, GET_MODE (from))
+ == GET_MODE_BITSIZE (GET_MODE (from))))
+ false_code = EQ, false_val = constm1_rtx;
- /* Look for cases where we have (abs x) or (neg (abs X)). */
+ /* Now simplify an arm if we know the value of the register in the
+ branch and it is used in the arm. Be careful due to the potential
+ of locally-shared RTL. */
- if (GET_MODE_CLASS (mode) == MODE_INT
- && GET_CODE (XEXP (x, 2)) == NEG
- && rtx_equal_p (XEXP (x, 1), XEXP (XEXP (x, 2), 0))
- && GET_RTX_CLASS (GET_CODE (XEXP (x, 0))) == '<'
- && rtx_equal_p (XEXP (x, 1), XEXP (XEXP (x, 0), 0))
- && ! side_effects_p (XEXP (x, 1)))
- switch (GET_CODE (XEXP (x, 0)))
- {
- case GT:
- case GE:
- x = gen_unary (ABS, mode, XEXP (x, 1));
- goto restart;
- case LT:
- case LE:
- x = gen_unary (NEG, mode, gen_unary (ABS, mode, XEXP (x, 1)));
- goto restart;
- }
+ if (reg_mentioned_p (from, true))
+ true = subst (known_cond (copy_rtx (true), true_code, from, true_val),
+ pc_rtx, pc_rtx, 0, 0);
+ if (reg_mentioned_p (from, false))
+ false = subst (known_cond (copy_rtx (false), false_code,
+ from, false_val),
+ pc_rtx, pc_rtx, 0, 0);
- /* Look for MIN or MAX. */
+ SUBST (XEXP (x, 1), swapped ? false : true);
+ SUBST (XEXP (x, 2), swapped ? true : false);
- if (! FLOAT_MODE_P (mode)
- && GET_RTX_CLASS (GET_CODE (XEXP (x, 0))) == '<'
- && rtx_equal_p (XEXP (XEXP (x, 0), 0), XEXP (x, 1))
- && rtx_equal_p (XEXP (XEXP (x, 0), 1), XEXP (x, 2))
- && ! side_effects_p (XEXP (x, 0)))
- switch (GET_CODE (XEXP (x, 0)))
- {
- case GE:
- case GT:
- x = gen_binary (SMAX, mode, XEXP (x, 1), XEXP (x, 2));
- goto restart;
- case LE:
- case LT:
- x = gen_binary (SMIN, mode, XEXP (x, 1), XEXP (x, 2));
- goto restart;
- case GEU:
- case GTU:
- x = gen_binary (UMAX, mode, XEXP (x, 1), XEXP (x, 2));
- goto restart;
- case LEU:
- case LTU:
- x = gen_binary (UMIN, mode, XEXP (x, 1), XEXP (x, 2));
- goto restart;
- }
+ true = XEXP (x, 1), false = XEXP (x, 2), true_code = GET_CODE (cond);
+ }
-#if STORE_FLAG_VALUE == 1 || STORE_FLAG_VALUE == -1
+ /* If we have (if_then_else FOO (pc) (label_ref BAR)) and FOO can be
+ reversed, do so to avoid needing two sets of patterns for
+ subtract-and-branch insns. Similarly if we have a constant in the true
+ arm, the false arm is the same as the first operand of the comparison, or
+ the false arm is more complicated than the true arm. */
+
+ if (comparison_p && reversible_comparison_p (cond)
+ && (true == pc_rtx
+ || (CONSTANT_P (true)
+ && GET_CODE (false) != CONST_INT && false != pc_rtx)
+ || true == const0_rtx
+ || (GET_RTX_CLASS (GET_CODE (true)) == 'o'
+ && GET_RTX_CLASS (GET_CODE (false)) != 'o')
+ || (GET_CODE (true) == SUBREG
+ && GET_RTX_CLASS (GET_CODE (SUBREG_REG (true))) == 'o'
+ && GET_RTX_CLASS (GET_CODE (false)) != 'o')
+ || reg_mentioned_p (true, false)
+ || rtx_equal_p (false, XEXP (cond, 0))))
+ {
+ true_code = reverse_condition (true_code);
+ SUBST (XEXP (x, 0),
+ gen_binary (true_code, GET_MODE (cond), XEXP (cond, 0),
+ XEXP (cond, 1)));
- /* If we have (if_then_else COND (OP Z C1) Z) and OP is an identity when
- its second operand is zero, this can be done as (OP Z (mult COND C2))
- where C2 = C1 * STORE_FLAG_VALUE. Similarly if OP has an outer
- ZERO_EXTEND or SIGN_EXTEND as long as Z is already extended (so
- we don't destroy it). We can do this kind of thing in some
- cases when STORE_FLAG_VALUE is neither of the above, but it isn't
- worth checking for.
+ SUBST (XEXP (x, 1), false);
+ SUBST (XEXP (x, 2), true);
- Similarly, (if_then_else COND Z 0) can be replaced by
- (mult COND (mult Z STORE_FLAG_VALUE)). */
+ temp = true, true = false, false = temp, cond = XEXP (x, 0);
+ }
- if (mode != VOIDmode && ! side_effects_p (x))
- {
- rtx t = make_compound_operation (XEXP (x, 1), SET);
- rtx f = make_compound_operation (XEXP (x, 2), SET);
- rtx cond_op0 = XEXP (XEXP (x, 0), 0);
- rtx cond_op1 = XEXP (XEXP (x, 0), 1);
- enum rtx_code cond_op = GET_CODE (XEXP (x, 0));
- enum rtx_code op, extend_op = NIL;
- enum machine_mode m = mode;
- rtx z = 0, c1, c2;
-
- if (f == const0_rtx)
- return gen_binary (MULT, mode, gen_binary (cond_op, mode, cond_op0,
- cond_op1),
- gen_binary (MULT, mode, t, const_true_rtx));
-
- if ((GET_CODE (t) == PLUS || GET_CODE (t) == MINUS
- || GET_CODE (t) == IOR || GET_CODE (t) == XOR
- || GET_CODE (t) == ASHIFT
- || GET_CODE (t) == LSHIFTRT || GET_CODE (t) == ASHIFTRT)
- && rtx_equal_p (XEXP (t, 0), f))
- c1 = XEXP (t, 1), op = GET_CODE (t), z = f;
-
- /* If an identity-zero op is commutative, check whether there
- would be a match if we swapped the operands. */
- else if ((GET_CODE (t) == PLUS || GET_CODE (t) == IOR
- || GET_CODE (t) == XOR)
- && rtx_equal_p (XEXP (t, 1), f))
- c1 = XEXP (t, 0), op = GET_CODE (t), z = f;
- else if (GET_CODE (t) == SIGN_EXTEND
- && (GET_CODE (XEXP (t, 0)) == PLUS
- || GET_CODE (XEXP (t, 0)) == MINUS
- || GET_CODE (XEXP (t, 0)) == IOR
- || GET_CODE (XEXP (t, 0)) == XOR
- || GET_CODE (XEXP (t, 0)) == ASHIFT
- || GET_CODE (XEXP (t, 0)) == LSHIFTRT
- || GET_CODE (XEXP (t, 0)) == ASHIFTRT)
- && GET_CODE (XEXP (XEXP (t, 0), 0)) == SUBREG
- && subreg_lowpart_p (XEXP (XEXP (t, 0), 0))
- && rtx_equal_p (SUBREG_REG (XEXP (XEXP (t, 0), 0)), f)
- && (num_sign_bit_copies (f, GET_MODE (f))
- > (GET_MODE_BITSIZE (mode)
- - GET_MODE_BITSIZE (GET_MODE (XEXP (XEXP (t, 0),
- 0))))))
- {
- c1 = XEXP (XEXP (t, 0), 1); z = f; op = GET_CODE (XEXP (t, 0));
- extend_op = SIGN_EXTEND;
- m = GET_MODE (XEXP (t, 0));
- }
- else if (GET_CODE (t) == SIGN_EXTEND
- && (GET_CODE (XEXP (t, 0)) == PLUS
- || GET_CODE (XEXP (t, 0)) == IOR
- || GET_CODE (XEXP (t, 0)) == XOR)
- && GET_CODE (XEXP (XEXP (t, 0), 1)) == SUBREG
- && subreg_lowpart_p (XEXP (XEXP (t, 0), 1))
- && rtx_equal_p (SUBREG_REG (XEXP (XEXP (t, 0), 1)), f)
- && (num_sign_bit_copies (f, GET_MODE (f))
- > (GET_MODE_BITSIZE (mode)
- - GET_MODE_BITSIZE (GET_MODE (XEXP (XEXP (t, 0),
- 1))))))
- {
- c1 = XEXP (XEXP (t, 0), 0); z = f; op = GET_CODE (XEXP (t, 0));
- extend_op = SIGN_EXTEND;
- m = GET_MODE (XEXP (t, 0));
- }
- else if (GET_CODE (t) == ZERO_EXTEND
- && (GET_CODE (XEXP (t, 0)) == PLUS
- || GET_CODE (XEXP (t, 0)) == MINUS
- || GET_CODE (XEXP (t, 0)) == IOR
- || GET_CODE (XEXP (t, 0)) == XOR
- || GET_CODE (XEXP (t, 0)) == ASHIFT
- || GET_CODE (XEXP (t, 0)) == LSHIFTRT
- || GET_CODE (XEXP (t, 0)) == ASHIFTRT)
- && GET_CODE (XEXP (XEXP (t, 0), 0)) == SUBREG
- && GET_MODE_BITSIZE (mode) <= HOST_BITS_PER_WIDE_INT
- && subreg_lowpart_p (XEXP (XEXP (t, 0), 0))
- && rtx_equal_p (SUBREG_REG (XEXP (XEXP (t, 0), 0)), f)
- && ((nonzero_bits (f, GET_MODE (f))
- & ~ GET_MODE_MASK (GET_MODE (XEXP (XEXP (t, 0), 0))))
- == 0))
- {
- c1 = XEXP (XEXP (t, 0), 1); z = f; op = GET_CODE (XEXP (t, 0));
- extend_op = ZERO_EXTEND;
- m = GET_MODE (XEXP (t, 0));
- }
- else if (GET_CODE (t) == ZERO_EXTEND
- && (GET_CODE (XEXP (t, 0)) == PLUS
- || GET_CODE (XEXP (t, 0)) == IOR
- || GET_CODE (XEXP (t, 0)) == XOR)
- && GET_CODE (XEXP (XEXP (t, 0), 1)) == SUBREG
- && GET_MODE_BITSIZE (mode) <= HOST_BITS_PER_WIDE_INT
- && subreg_lowpart_p (XEXP (XEXP (t, 0), 1))
- && rtx_equal_p (SUBREG_REG (XEXP (XEXP (t, 0), 1)), f)
- && ((nonzero_bits (f, GET_MODE (f))
- & ~ GET_MODE_MASK (GET_MODE (XEXP (XEXP (t, 0), 1))))
- == 0))
- {
- c1 = XEXP (XEXP (t, 0), 0); z = f; op = GET_CODE (XEXP (t, 0));
- extend_op = ZERO_EXTEND;
- m = GET_MODE (XEXP (t, 0));
- }
+ /* If the two arms are identical, we don't need the comparison. */
- if (z)
- {
- temp = subst (gen_binary (cond_op, m, cond_op0, cond_op1),
- pc_rtx, pc_rtx, 0, 0);
+ if (rtx_equal_p (true, false) && ! side_effects_p (cond))
+ return true;
+ /* Look for cases where we have (abs x) or (neg (abs X)). */
- temp = gen_binary (MULT, m, temp,
- gen_binary (MULT, m, c1, const_true_rtx));
+ if (GET_MODE_CLASS (mode) == MODE_INT
+ && GET_CODE (false) == NEG
+ && rtx_equal_p (true, XEXP (false, 0))
+ && comparison_p
+ && rtx_equal_p (true, XEXP (cond, 0))
+ && ! side_effects_p (true))
+ switch (true_code)
+ {
+ case GT:
+ case GE:
+ return gen_unary (ABS, mode, true);
+ case LT:
+ case LE:
+ return gen_unary (NEG, mode, gen_unary (ABS, mode, true));
+ }
- temp = subst (temp, pc_rtx, pc_rtx, 0, 0);
+ /* Look for MIN or MAX. */
+
+ if ((! FLOAT_MODE_P (mode) | flag_fast_math)
+ && comparison_p
+ && rtx_equal_p (XEXP (cond, 0), true)
+ && rtx_equal_p (XEXP (cond, 1), false)
+ && ! side_effects_p (cond))
+ switch (true_code)
+ {
+ case GE:
+ case GT:
+ return gen_binary (SMAX, mode, true, false);
+ case LE:
+ case LT:
+ return gen_binary (SMIN, mode, true, false);
+ case GEU:
+ case GTU:
+ return gen_binary (UMAX, mode, true, false);
+ case LEU:
+ case LTU:
+ return gen_binary (UMIN, mode, true, false);
+ }
+
+#if STORE_FLAG_VALUE == 1 || STORE_FLAG_VALUE == -1
- temp = gen_binary (op, m, gen_lowpart_for_combine (m, z), temp);
+ /* If we have (if_then_else COND (OP Z C1) Z) and OP is an identity when its
+ second operand is zero, this can be done as (OP Z (mult COND C2)) where
+ C2 = C1 * STORE_FLAG_VALUE. Similarly if OP has an outer ZERO_EXTEND or
+ SIGN_EXTEND as long as Z is already extended (so we don't destroy it).
+ We can do this kind of thing in some cases when STORE_FLAG_VALUE is
+ neither of the above, but it isn't worth checking for.
- if (extend_op != NIL)
- temp = gen_unary (extend_op, mode, temp);
+ Similarly, (if_then_else COND Z 0) can be replaced by
+ (mult COND (mult Z STORE_FLAG_VALUE)). */
- return temp;
- }
+ if (comparison_p && mode != VOIDmode && ! side_effects_p (x))
+ {
+ rtx t = make_compound_operation (true, SET);
+ rtx f = make_compound_operation (false, SET);
+ rtx cond_op0 = XEXP (cond, 0);
+ rtx cond_op1 = XEXP (cond, 1);
+ enum rtx_code op, extend_op = NIL;
+ enum machine_mode m = mode;
+ rtx z = 0, c1, c2;
+
+ if (f == const0_rtx)
+ return gen_binary (MULT, mode, gen_binary (true_code, mode, cond_op0,
+ cond_op1),
+ gen_binary (MULT, mode, t, const_true_rtx));
+
+ if ((GET_CODE (t) == PLUS || GET_CODE (t) == MINUS
+ || GET_CODE (t) == IOR || GET_CODE (t) == XOR
+ || GET_CODE (t) == ASHIFT
+ || GET_CODE (t) == LSHIFTRT || GET_CODE (t) == ASHIFTRT)
+ && rtx_equal_p (XEXP (t, 0), f))
+ c1 = XEXP (t, 1), op = GET_CODE (t), z = f;
+
+ /* If an identity-zero op is commutative, check whether there
+ would be a match if we swapped the operands. */
+ else if ((GET_CODE (t) == PLUS || GET_CODE (t) == IOR
+ || GET_CODE (t) == XOR)
+ && rtx_equal_p (XEXP (t, 1), f))
+ c1 = XEXP (t, 0), op = GET_CODE (t), z = f;
+ else if (GET_CODE (t) == SIGN_EXTEND
+ && (GET_CODE (XEXP (t, 0)) == PLUS
+ || GET_CODE (XEXP (t, 0)) == MINUS
+ || GET_CODE (XEXP (t, 0)) == IOR
+ || GET_CODE (XEXP (t, 0)) == XOR
+ || GET_CODE (XEXP (t, 0)) == ASHIFT
+ || GET_CODE (XEXP (t, 0)) == LSHIFTRT
+ || GET_CODE (XEXP (t, 0)) == ASHIFTRT)
+ && GET_CODE (XEXP (XEXP (t, 0), 0)) == SUBREG
+ && subreg_lowpart_p (XEXP (XEXP (t, 0), 0))
+ && rtx_equal_p (SUBREG_REG (XEXP (XEXP (t, 0), 0)), f)
+ && (num_sign_bit_copies (f, GET_MODE (f))
+ > (GET_MODE_BITSIZE (mode)
+ - GET_MODE_BITSIZE (GET_MODE (XEXP (XEXP (t, 0), 0))))))
+ {
+ c1 = XEXP (XEXP (t, 0), 1); z = f; op = GET_CODE (XEXP (t, 0));
+ extend_op = SIGN_EXTEND;
+ m = GET_MODE (XEXP (t, 0));
+ }
+ else if (GET_CODE (t) == SIGN_EXTEND
+ && (GET_CODE (XEXP (t, 0)) == PLUS
+ || GET_CODE (XEXP (t, 0)) == IOR
+ || GET_CODE (XEXP (t, 0)) == XOR)
+ && GET_CODE (XEXP (XEXP (t, 0), 1)) == SUBREG
+ && subreg_lowpart_p (XEXP (XEXP (t, 0), 1))
+ && rtx_equal_p (SUBREG_REG (XEXP (XEXP (t, 0), 1)), f)
+ && (num_sign_bit_copies (f, GET_MODE (f))
+ > (GET_MODE_BITSIZE (mode)
+ - GET_MODE_BITSIZE (GET_MODE (XEXP (XEXP (t, 0), 1))))))
+ {
+ c1 = XEXP (XEXP (t, 0), 0); z = f; op = GET_CODE (XEXP (t, 0));
+ extend_op = SIGN_EXTEND;
+ m = GET_MODE (XEXP (t, 0));
+ }
+ else if (GET_CODE (t) == ZERO_EXTEND
+ && (GET_CODE (XEXP (t, 0)) == PLUS
+ || GET_CODE (XEXP (t, 0)) == MINUS
+ || GET_CODE (XEXP (t, 0)) == IOR
+ || GET_CODE (XEXP (t, 0)) == XOR
+ || GET_CODE (XEXP (t, 0)) == ASHIFT
+ || GET_CODE (XEXP (t, 0)) == LSHIFTRT
+ || GET_CODE (XEXP (t, 0)) == ASHIFTRT)
+ && GET_CODE (XEXP (XEXP (t, 0), 0)) == SUBREG
+ && GET_MODE_BITSIZE (mode) <= HOST_BITS_PER_WIDE_INT
+ && subreg_lowpart_p (XEXP (XEXP (t, 0), 0))
+ && rtx_equal_p (SUBREG_REG (XEXP (XEXP (t, 0), 0)), f)
+ && ((nonzero_bits (f, GET_MODE (f))
+ & ~ GET_MODE_MASK (GET_MODE (XEXP (XEXP (t, 0), 0))))
+ == 0))
+ {
+ c1 = XEXP (XEXP (t, 0), 1); z = f; op = GET_CODE (XEXP (t, 0));
+ extend_op = ZERO_EXTEND;
+ m = GET_MODE (XEXP (t, 0));
+ }
+ else if (GET_CODE (t) == ZERO_EXTEND
+ && (GET_CODE (XEXP (t, 0)) == PLUS
+ || GET_CODE (XEXP (t, 0)) == IOR
+ || GET_CODE (XEXP (t, 0)) == XOR)
+ && GET_CODE (XEXP (XEXP (t, 0), 1)) == SUBREG
+ && GET_MODE_BITSIZE (mode) <= HOST_BITS_PER_WIDE_INT
+ && subreg_lowpart_p (XEXP (XEXP (t, 0), 1))
+ && rtx_equal_p (SUBREG_REG (XEXP (XEXP (t, 0), 1)), f)
+ && ((nonzero_bits (f, GET_MODE (f))
+ & ~ GET_MODE_MASK (GET_MODE (XEXP (XEXP (t, 0), 1))))
+ == 0))
+ {
+ c1 = XEXP (XEXP (t, 0), 0); z = f; op = GET_CODE (XEXP (t, 0));
+ extend_op = ZERO_EXTEND;
+ m = GET_MODE (XEXP (t, 0));
}
+
+ if (z)
+ {
+ temp = subst (gen_binary (true_code, m, cond_op0, cond_op1),
+ pc_rtx, pc_rtx, 0, 0);
+ temp = gen_binary (MULT, m, temp,
+ gen_binary (MULT, m, c1, const_true_rtx));
+ temp = subst (temp, pc_rtx, pc_rtx, 0, 0);
+ temp = gen_binary (op, m, gen_lowpart_for_combine (m, z), temp);
+
+ if (extend_op != NIL)
+ temp = gen_unary (extend_op, mode, temp);
+
+ return temp;
+ }
+ }
#endif
- /* If we have (if_then_else (ne A 0) C1 0) and either A is known to
- be 0 or 1 and C1 is a single bit or A is known to be 0 or -1 and
- C1 is the negation of a single bit, we can convert this operation
- to a shift. We can actually do this in more general cases, but it
- doesn't seem worth it. */
+ /* If we have (if_then_else (ne A 0) C1 0) and either A is known to be 0 or
+ 1 and C1 is a single bit or A is known to be 0 or -1 and C1 is the
+ negation of a single bit, we can convert this operation to a shift. We
+ can actually do this more generally, but it doesn't seem worth it. */
+
+ if (true_code == NE && XEXP (cond, 1) == const0_rtx
+ && false == const0_rtx && GET_CODE (true) == CONST_INT
+ && ((1 == nonzero_bits (XEXP (cond, 0), mode)
+ && (i = exact_log2 (INTVAL (true))) >= 0)
+ || ((num_sign_bit_copies (XEXP (cond, 0), mode)
+ == GET_MODE_BITSIZE (mode))
+ && (i = exact_log2 (- INTVAL (true))) >= 0)))
+ return
+ simplify_shift_const (NULL_RTX, ASHIFT, mode,
+ gen_lowpart_for_combine (mode, XEXP (cond, 0)), i);
- if (GET_CODE (XEXP (x, 0)) == NE && XEXP (XEXP (x, 0), 1) == const0_rtx
- && XEXP (x, 2) == const0_rtx && GET_CODE (XEXP (x, 1)) == CONST_INT
- && ((1 == nonzero_bits (XEXP (XEXP (x, 0), 0), mode)
- && (i = exact_log2 (INTVAL (XEXP (x, 1)))) >= 0)
- || ((num_sign_bit_copies (XEXP (XEXP (x, 0), 0), mode)
- == GET_MODE_BITSIZE (mode))
- && (i = exact_log2 (- INTVAL (XEXP (x, 1)))) >= 0)))
- return
- simplify_shift_const (NULL_RTX, ASHIFT, mode,
- gen_lowpart_for_combine (mode,
- XEXP (XEXP (x, 0), 0)),
- i);
- break;
-
- case ZERO_EXTRACT:
- case SIGN_EXTRACT:
- case ZERO_EXTEND:
- case SIGN_EXTEND:
- /* If we are processing SET_DEST, we are done. */
- if (in_dest)
- return x;
+ return x;
+}
+\f
+/* Simplify X, a SET expression. Return the new expression. */
- x = expand_compound_operation (x);
- if (GET_CODE (x) != code)
- goto restart;
- break;
+static rtx
+simplify_set (x)
+ rtx x;
+{
+ rtx src = SET_SRC (x);
+ rtx dest = SET_DEST (x);
+ enum machine_mode mode
+ = GET_MODE (src) != VOIDmode ? GET_MODE (src) : GET_MODE (dest);
+ rtx other_insn;
+ rtx *cc_use;
- case SET:
- /* (set (pc) (return)) gets written as (return). */
- if (GET_CODE (SET_DEST (x)) == PC && GET_CODE (SET_SRC (x)) == RETURN)
- return SET_SRC (x);
+ /* (set (pc) (return)) gets written as (return). */
+ if (GET_CODE (dest) == PC && GET_CODE (src) == RETURN)
+ return src;
- /* Convert this into a field assignment operation, if possible. */
- x = make_field_assignment (x);
+ /* Convert this into a field assignment operation, if possible. */
+ x = make_field_assignment (x);
- /* If we are setting CC0 or if the source is a COMPARE, look for the
- use of the comparison result and try to simplify it unless we already
- have used undobuf.other_insn. */
- if ((GET_CODE (SET_SRC (x)) == COMPARE
+ /* If we are setting CC0 or if the source is a COMPARE, look for the use of
+ the comparison result and try to simplify it unless we already have used
+ undobuf.other_insn. */
+ if ((GET_CODE (src) == COMPARE
#ifdef HAVE_cc0
- || SET_DEST (x) == cc0_rtx
+ || dest == cc0_rtx
#endif
- )
- && (cc_use = find_single_use (SET_DEST (x), subst_insn,
- &other_insn)) != 0
- && (undobuf.other_insn == 0 || other_insn == undobuf.other_insn)
- && GET_RTX_CLASS (GET_CODE (*cc_use)) == '<'
- && XEXP (*cc_use, 0) == SET_DEST (x))
- {
- enum rtx_code old_code = GET_CODE (*cc_use);
- enum rtx_code new_code;
- rtx op0, op1;
- int other_changed = 0;
- enum machine_mode compare_mode = GET_MODE (SET_DEST (x));
-
- if (GET_CODE (SET_SRC (x)) == COMPARE)
- op0 = XEXP (SET_SRC (x), 0), op1 = XEXP (SET_SRC (x), 1);
- else
- op0 = SET_SRC (x), op1 = const0_rtx;
+ )
+ && (cc_use = find_single_use (dest, subst_insn, &other_insn)) != 0
+ && (undobuf.other_insn == 0 || other_insn == undobuf.other_insn)
+ && GET_RTX_CLASS (GET_CODE (*cc_use)) == '<'
+ && XEXP (*cc_use, 0) == dest)
+ {
+ enum rtx_code old_code = GET_CODE (*cc_use);
+ enum rtx_code new_code;
+ rtx op0, op1;
+ int other_changed = 0;
+ enum machine_mode compare_mode = GET_MODE (dest);
+
+ if (GET_CODE (src) == COMPARE)
+ op0 = XEXP (src, 0), op1 = XEXP (src, 1);
+ else
+ op0 = src, op1 = const0_rtx;
- /* Simplify our comparison, if possible. */
- new_code = simplify_comparison (old_code, &op0, &op1);
+ /* Simplify our comparison, if possible. */
+ new_code = simplify_comparison (old_code, &op0, &op1);
#ifdef EXTRA_CC_MODES
- /* If this machine has CC modes other than CCmode, check to see
- if we need to use a different CC mode here. */
- compare_mode = SELECT_CC_MODE (new_code, op0, op1);
+ /* If this machine has CC modes other than CCmode, check to see if we
+ need to use a different CC mode here. */
+ compare_mode = SELECT_CC_MODE (new_code, op0, op1);
#endif /* EXTRA_CC_MODES */
#if !defined (HAVE_cc0) && defined (EXTRA_CC_MODES)
- /* If the mode changed, we have to change SET_DEST, the mode
- in the compare, and the mode in the place SET_DEST is used.
- If SET_DEST is a hard register, just build new versions with
- the proper mode. If it is a pseudo, we lose unless it is only
- time we set the pseudo, in which case we can safely change
- its mode. */
- if (compare_mode != GET_MODE (SET_DEST (x)))
+ /* If the mode changed, we have to change SET_DEST, the mode in the
+ compare, and the mode in the place SET_DEST is used. If SET_DEST is
+ a hard register, just build new versions with the proper mode. If it
+ is a pseudo, we lose unless it is only time we set the pseudo, in
+ which case we can safely change its mode. */
+ if (compare_mode != GET_MODE (dest))
+ {
+ int regno = REGNO (dest);
+ rtx new_dest = gen_rtx (REG, compare_mode, regno);
+
+ if (regno < FIRST_PSEUDO_REGISTER
+ || (reg_n_sets[regno] == 1 && ! REG_USERVAR_P (dest)))
{
- int regno = REGNO (SET_DEST (x));
- rtx new_dest = gen_rtx (REG, compare_mode, regno);
+ if (regno >= FIRST_PSEUDO_REGISTER)
+ SUBST (regno_reg_rtx[regno], new_dest);
- if (regno < FIRST_PSEUDO_REGISTER
- || (reg_n_sets[regno] == 1
- && ! REG_USERVAR_P (SET_DEST (x))))
- {
- if (regno >= FIRST_PSEUDO_REGISTER)
- SUBST (regno_reg_rtx[regno], new_dest);
+ SUBST (SET_DEST (x), new_dest);
+ SUBST (XEXP (*cc_use, 0), new_dest);
+ other_changed = 1;
- SUBST (SET_DEST (x), new_dest);
- SUBST (XEXP (*cc_use, 0), new_dest);
- other_changed = 1;
- }
+ dest = new_dest;
}
+ }
#endif
- /* If the code changed, we have to build a new comparison
- in undobuf.other_insn. */
- if (new_code != old_code)
+ /* If the code changed, we have to build a new comparison in
+ undobuf.other_insn. */
+ if (new_code != old_code)
+ {
+ unsigned HOST_WIDE_INT mask;
+
+ SUBST (*cc_use, gen_rtx_combine (new_code, GET_MODE (*cc_use),
+ dest, const0_rtx));
+
+ /* If the only change we made was to change an EQ into an NE or
+ vice versa, OP0 has only one bit that might be nonzero, and OP1
+ is zero, check if changing the user of the condition code will
+ produce a valid insn. If it won't, we can keep the original code
+ in that insn by surrounding our operation with an XOR. */
+
+ if (((old_code == NE && new_code == EQ)
+ || (old_code == EQ && new_code == NE))
+ && ! other_changed && op1 == const0_rtx
+ && GET_MODE_BITSIZE (GET_MODE (op0)) <= HOST_BITS_PER_WIDE_INT
+ && exact_log2 (mask = nonzero_bits (op0, GET_MODE (op0))) >= 0)
{
- unsigned HOST_WIDE_INT mask;
+ rtx pat = PATTERN (other_insn), note = 0;
- SUBST (*cc_use, gen_rtx_combine (new_code, GET_MODE (*cc_use),
- SET_DEST (x), const0_rtx));
-
- /* If the only change we made was to change an EQ into an
- NE or vice versa, OP0 has only one bit that might be nonzero,
- and OP1 is zero, check if changing the user of the condition
- code will produce a valid insn. If it won't, we can keep
- the original code in that insn by surrounding our operation
- with an XOR. */
-
- if (((old_code == NE && new_code == EQ)
- || (old_code == EQ && new_code == NE))
- && ! other_changed && op1 == const0_rtx
- && (GET_MODE_BITSIZE (GET_MODE (op0))
- <= HOST_BITS_PER_WIDE_INT)
- && (exact_log2 (mask = nonzero_bits (op0, GET_MODE (op0)))
- >= 0))
+ if ((recog_for_combine (&pat, other_insn, ¬e) < 0
+ && ! check_asm_operands (pat)))
{
- rtx pat = PATTERN (other_insn), note = 0;
+ PUT_CODE (*cc_use, old_code);
+ other_insn = 0;
- if ((recog_for_combine (&pat, other_insn, ¬e) < 0
- && ! check_asm_operands (pat)))
- {
- PUT_CODE (*cc_use, old_code);
- other_insn = 0;
-
- op0 = gen_binary (XOR, GET_MODE (op0), op0,
- GEN_INT (mask));
- }
+ op0 = gen_binary (XOR, GET_MODE (op0), op0, GEN_INT (mask));
}
-
- other_changed = 1;
}
- if (other_changed)
- undobuf.other_insn = other_insn;
+ other_changed = 1;
+ }
+
+ if (other_changed)
+ undobuf.other_insn = other_insn;
#ifdef HAVE_cc0
- /* If we are now comparing against zero, change our source if
- needed. If we do not use cc0, we always have a COMPARE. */
- if (op1 == const0_rtx && SET_DEST (x) == cc0_rtx)
- SUBST (SET_SRC (x), op0);
- else
+ /* If we are now comparing against zero, change our source if
+ needed. If we do not use cc0, we always have a COMPARE. */
+ if (op1 == const0_rtx && dest == cc0_rtx)
+ {
+ SUBST (SET_SRC (x), op0);
+ src = op0;
+ }
+ else
#endif
- /* Otherwise, if we didn't previously have a COMPARE in the
- correct mode, we need one. */
- if (GET_CODE (SET_SRC (x)) != COMPARE
- || GET_MODE (SET_SRC (x)) != compare_mode)
- SUBST (SET_SRC (x), gen_rtx_combine (COMPARE, compare_mode,
- op0, op1));
- else
- {
- /* Otherwise, update the COMPARE if needed. */
- SUBST (XEXP (SET_SRC (x), 0), op0);
- SUBST (XEXP (SET_SRC (x), 1), op1);
- }
+ /* Otherwise, if we didn't previously have a COMPARE in the
+ correct mode, we need one. */
+ if (GET_CODE (src) != COMPARE || GET_MODE (src) != compare_mode)
+ {
+ SUBST (SET_SRC (x),
+ gen_rtx_combine (COMPARE, compare_mode, op0, op1));
+ src = SET_SRC (x);
}
else
{
- /* Get SET_SRC in a form where we have placed back any
- compound expressions. Then do the checks below. */
- temp = make_compound_operation (SET_SRC (x), SET);
- SUBST (SET_SRC (x), temp);
+ /* Otherwise, update the COMPARE if needed. */
+ SUBST (XEXP (src, 0), op0);
+ SUBST (XEXP (src, 1), op1);
}
+ }
+ else
+ {
+ /* Get SET_SRC in a form where we have placed back any
+ compound expressions. Then do the checks below. */
+ src = make_compound_operation (src, SET);
+ SUBST (SET_SRC (x), src);
+ }
- /* If we have (set x (subreg:m1 (op:m2 ...) 0)) with OP being some
- operation, and X being a REG or (subreg (reg)), we may be able to
- convert this to (set (subreg:m2 x) (op)).
+ /* If we have (set x (subreg:m1 (op:m2 ...) 0)) with OP being some operation,
+ and X being a REG or (subreg (reg)), we may be able to convert this to
+ (set (subreg:m2 x) (op)).
- We can always do this if M1 is narrower than M2 because that
- means that we only care about the low bits of the result.
+ We can always do this if M1 is narrower than M2 because that means that
+ we only care about the low bits of the result.
- However, on machines without WORD_REGISTER_OPERATIONS defined,
- we cannot perform a narrower operation that requested since the
- high-order bits will be undefined. On machine where it is defined,
- this transformation is safe as long as M1 and M2 have the same
- number of words. */
+ However, on machines without WORD_REGISTER_OPERATIONS defined, we cannot
+ perform a narrower operation that requested since the high-order bits will
+ be undefined. On machine where it is defined, this transformation is safe
+ as long as M1 and M2 have the same number of words. */
- if (GET_CODE (SET_SRC (x)) == SUBREG
- && subreg_lowpart_p (SET_SRC (x))
- && GET_RTX_CLASS (GET_CODE (SUBREG_REG (SET_SRC (x)))) != 'o'
- && (((GET_MODE_SIZE (GET_MODE (SET_SRC (x))) + (UNITS_PER_WORD - 1))
- / UNITS_PER_WORD)
- == ((GET_MODE_SIZE (GET_MODE (SUBREG_REG (SET_SRC (x))))
- + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD))
+ if (GET_CODE (src) == SUBREG && subreg_lowpart_p (src)
+ && GET_RTX_CLASS (GET_CODE (SUBREG_REG (src))) != 'o'
+ && (((GET_MODE_SIZE (GET_MODE (src)) + (UNITS_PER_WORD - 1))
+ / UNITS_PER_WORD)
+ == ((GET_MODE_SIZE (GET_MODE (SUBREG_REG (src)))
+ + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD))
#ifndef WORD_REGISTER_OPERATIONS
- && (GET_MODE_SIZE (GET_MODE (SET_SRC (x)))
- < GET_MODE_SIZE (GET_MODE (SUBREG_REG (SET_SRC (x)))))
+ && (GET_MODE_SIZE (GET_MODE (src))
+ < GET_MODE_SIZE (GET_MODE (SUBREG_REG (src))))
#endif
- && (GET_CODE (SET_DEST (x)) == REG
- || (GET_CODE (SET_DEST (x)) == SUBREG
- && GET_CODE (SUBREG_REG (SET_DEST (x))) == REG)))
- {
- SUBST (SET_DEST (x),
- gen_lowpart_for_combine (GET_MODE (SUBREG_REG (SET_SRC (x))),
- SET_DEST (x)));
- SUBST (SET_SRC (x), SUBREG_REG (SET_SRC (x)));
- }
+ && (GET_CODE (dest) == REG
+ || (GET_CODE (dest) == SUBREG
+ && GET_CODE (SUBREG_REG (dest)) == REG)))
+ {
+ SUBST (SET_DEST (x),
+ gen_lowpart_for_combine (GET_MODE (SUBREG_REG (src)),
+ dest));
+ SUBST (SET_SRC (x), SUBREG_REG (src));
+
+ src = SET_SRC (x), dest = SET_DEST (x);
+ }
#ifdef LOAD_EXTEND_OP
- /* If we have (set FOO (subreg:M (mem:N BAR) 0)) with
- M wider than N, this would require a paradoxical subreg.
- Replace the subreg with a zero_extend to avoid the reload that
- would otherwise be required. */
-
- if (GET_CODE (SET_SRC (x)) == SUBREG
- && LOAD_EXTEND_OP (GET_MODE (SUBREG_REG (SET_SRC (x)))) != NIL
- && subreg_lowpart_p (SET_SRC (x))
- && SUBREG_WORD (SET_SRC (x)) == 0
- && (GET_MODE_SIZE (GET_MODE (SET_SRC (x)))
- > GET_MODE_SIZE (GET_MODE (SUBREG_REG (SET_SRC (x)))))
- && GET_CODE (SUBREG_REG (SET_SRC (x))) == MEM)
- SUBST (SET_SRC (x),
- gen_rtx_combine (LOAD_EXTEND_OP (GET_MODE
- (SUBREG_REG (SET_SRC (x)))),
- GET_MODE (SET_SRC (x)),
- XEXP (SET_SRC (x), 0)));
+ /* If we have (set FOO (subreg:M (mem:N BAR) 0)) with M wider than N, this
+ would require a paradoxical subreg. Replace the subreg with a
+ zero_extend to avoid the reload that would otherwise be required. */
+
+ if (GET_CODE (src) == SUBREG && subreg_lowpart_p (src)
+ && LOAD_EXTEND_OP (GET_MODE (SUBREG_REG (src))) != NIL
+ && SUBREG_WORD (src) == 0
+ && (GET_MODE_SIZE (GET_MODE (src))
+ > GET_MODE_SIZE (GET_MODE (SUBREG_REG (src))))
+ && GET_CODE (SUBREG_REG (src)) == MEM)
+ {
+ SUBST (SET_SRC (x),
+ gen_rtx_combine (LOAD_EXTEND_OP (GET_MODE (SUBREG_REG (src))),
+ GET_MODE (src), XEXP (src, 0)));
+
+ src = SET_SRC (x);
+ }
#endif
#ifndef HAVE_conditional_move
- /* If we don't have a conditional move, SET_SRC is an IF_THEN_ELSE,
- and we are comparing an item known to be 0 or -1 against 0, use a
- logical operation instead. Check for one of the arms being an IOR
- of the other arm with some value. We compute three terms to be
- IOR'ed together. In practice, at most two will be nonzero. Then
- we do the IOR's. */
-
- if (GET_CODE (SET_DEST (x)) != PC
- && GET_CODE (SET_SRC (x)) == IF_THEN_ELSE
- && (GET_CODE (XEXP (SET_SRC (x), 0)) == EQ
- || GET_CODE (XEXP (SET_SRC (x), 0)) == NE)
- && XEXP (XEXP (SET_SRC (x), 0), 1) == const0_rtx
- && (num_sign_bit_copies (XEXP (XEXP (SET_SRC (x), 0), 0),
- GET_MODE (XEXP (XEXP (SET_SRC (x), 0), 0)))
- == GET_MODE_BITSIZE (GET_MODE (XEXP (XEXP (SET_SRC (x), 0), 0))))
- && ! side_effects_p (SET_SRC (x)))
- {
- rtx true = (GET_CODE (XEXP (SET_SRC (x), 0)) == NE
- ? XEXP (SET_SRC (x), 1) : XEXP (SET_SRC (x), 2));
- rtx false = (GET_CODE (XEXP (SET_SRC (x), 0)) == NE
- ? XEXP (SET_SRC (x), 2) : XEXP (SET_SRC (x), 1));
- rtx term1 = const0_rtx, term2, term3;
-
- if (GET_CODE (true) == IOR && rtx_equal_p (XEXP (true, 0), false))
- term1 = false, true = XEXP (true, 1), false = const0_rtx;
- else if (GET_CODE (true) == IOR
- && rtx_equal_p (XEXP (true, 1), false))
- term1 = false, true = XEXP (true, 0), false = const0_rtx;
- else if (GET_CODE (false) == IOR
- && rtx_equal_p (XEXP (false, 0), true))
- term1 = true, false = XEXP (false, 1), true = const0_rtx;
- else if (GET_CODE (false) == IOR
- && rtx_equal_p (XEXP (false, 1), true))
- term1 = true, false = XEXP (false, 0), true = const0_rtx;
-
- term2 = gen_binary (AND, GET_MODE (SET_SRC (x)),
- XEXP (XEXP (SET_SRC (x), 0), 0), true);
- term3 = gen_binary (AND, GET_MODE (SET_SRC (x)),
- gen_unary (NOT, GET_MODE (SET_SRC (x)),
- XEXP (XEXP (SET_SRC (x), 0), 0)),
- false);
-
- SUBST (SET_SRC (x),
- gen_binary (IOR, GET_MODE (SET_SRC (x)),
- gen_binary (IOR, GET_MODE (SET_SRC (x)),
- term1, term2),
- term3));
- }
+ /* If we don't have a conditional move, SET_SRC is an IF_THEN_ELSE, and we
+ are comparing an item known to be 0 or -1 against 0, use a logical
+ operation instead. Check for one of the arms being an IOR of the other
+ arm with some value. We compute three terms to be IOR'ed together. In
+ practice, at most two will be nonzero. Then we do the IOR's. */
+
+ if (GET_CODE (dest) != PC
+ && GET_CODE (src) == IF_THEN_ELSE
+ && (GET_CODE (XEXP (src, 0)) == EQ || GET_CODE (XEXP (src, 0)) == NE)
+ && XEXP (XEXP (src, 0), 1) == const0_rtx
+ && (num_sign_bit_copies (XEXP (XEXP (src, 0), 0),
+ GET_MODE (XEXP (XEXP (src, 0), 0)))
+ == GET_MODE_BITSIZE (GET_MODE (XEXP (XEXP (src, 0), 0))))
+ && ! side_effects_p (src))
+ {
+ rtx true = (GET_CODE (XEXP (src, 0)) == NE
+ ? XEXP (src, 1) : XEXP (src, 2));
+ rtx false = (GET_CODE (XEXP (src, 0)) == NE
+ ? XEXP (src, 2) : XEXP (src, 1));
+ rtx term1 = const0_rtx, term2, term3;
+
+ if (GET_CODE (true) == IOR && rtx_equal_p (XEXP (true, 0), false))
+ term1 = false, true = XEXP (true, 1), false = const0_rtx;
+ else if (GET_CODE (true) == IOR
+ && rtx_equal_p (XEXP (true, 1), false))
+ term1 = false, true = XEXP (true, 0), false = const0_rtx;
+ else if (GET_CODE (false) == IOR
+ && rtx_equal_p (XEXP (false, 0), true))
+ term1 = true, false = XEXP (false, 1), true = const0_rtx;
+ else if (GET_CODE (false) == IOR
+ && rtx_equal_p (XEXP (false, 1), true))
+ term1 = true, false = XEXP (false, 0), true = const0_rtx;
+
+ term2 = gen_binary (AND, GET_MODE (src), XEXP (XEXP (src, 0), 0), true);
+ term3 = gen_binary (AND, GET_MODE (src),
+ gen_unary (NOT, GET_MODE (src),
+ XEXP (XEXP (src, 0), 0)),
+ false);
+
+ SUBST (SET_SRC (x),
+ gen_binary (IOR, GET_MODE (src),
+ gen_binary (IOR, GET_MODE (src), term1, term2),
+ term3));
+
+ src = SET_SRC (x);
+ }
#endif
- break;
+ return x;
+}
+\f
+/* Simplify, X, and AND, IOR, or XOR operation, and return the simplified
+ result. LAST is nonzero if this is the last retry. */
+
+static rtx
+simplify_logical (x, last)
+ rtx x;
+ int last;
+{
+ enum machine_mode mode = GET_MODE (x);
+ rtx op0 = XEXP (x, 0);
+ rtx op1 = XEXP (x, 1);
+
+ switch (GET_CODE (x))
+ {
case AND:
- if (GET_CODE (XEXP (x, 1)) == CONST_INT)
+ /* Convert (A ^ B) & A to A & (~ B) since the latter is often a single
+ insn (and may simplify more). */
+ if (GET_CODE (op0) == XOR
+ && rtx_equal_p (XEXP (op0, 0), op1)
+ && ! side_effects_p (op1))
+ x = gen_binary (AND, mode, gen_unary (NOT, mode, XEXP (op0, 1)), op1);
+
+ if (GET_CODE (op0) == XOR
+ && rtx_equal_p (XEXP (op0, 1), op1)
+ && ! side_effects_p (op1))
+ x = gen_binary (AND, mode, gen_unary (NOT, mode, XEXP (op0, 0)), op1);
+
+ /* Similarly for (~ (A ^ B)) & A. */
+ if (GET_CODE (op0) == NOT
+ && GET_CODE (XEXP (op0, 0)) == XOR
+ && rtx_equal_p (XEXP (XEXP (op0, 0), 0), op1)
+ && ! side_effects_p (op1))
+ x = gen_binary (AND, mode, XEXP (XEXP (op0, 0), 1), op1);
+
+ if (GET_CODE (op0) == NOT
+ && GET_CODE (XEXP (op0, 0)) == XOR
+ && rtx_equal_p (XEXP (XEXP (op0, 0), 1), op1)
+ && ! side_effects_p (op1))
+ x = gen_binary (AND, mode, XEXP (XEXP (op0, 0), 0), op1);
+
+ if (GET_CODE (op1) == CONST_INT)
{
- x = simplify_and_const_int (x, mode, XEXP (x, 0),
- INTVAL (XEXP (x, 1)));
+ x = simplify_and_const_int (x, mode, op0, INTVAL (op1));
/* If we have (ior (and (X C1) C2)) and the next restart would be
the last, simplify this by making C1 as small as possible
and then exit. */
- if (n_restarts >= 3 && GET_CODE (x) == IOR
- && GET_CODE (XEXP (x, 0)) == AND
- && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT
- && GET_CODE (XEXP (x, 1)) == CONST_INT)
- {
- temp = gen_binary (AND, mode, XEXP (XEXP (x, 0), 0),
- GEN_INT (INTVAL (XEXP (XEXP (x, 0), 1))
- & ~ INTVAL (XEXP (x, 1))));
- return gen_binary (IOR, mode, temp, XEXP (x, 1));
- }
+ if (last
+ && GET_CODE (x) == IOR && GET_CODE (op0) == AND
+ && GET_CODE (XEXP (op0, 1)) == CONST_INT
+ && GET_CODE (op1) == CONST_INT)
+ return gen_binary (IOR, mode,
+ gen_binary (AND, mode, XEXP (op0, 0),
+ GEN_INT (INTVAL (XEXP (op0, 1))
+ & ~ INTVAL (op1))), op1);
if (GET_CODE (x) != AND)
- goto restart;
+ return x;
}
/* Convert (A | B) & A to A. */
- if (GET_CODE (XEXP (x, 0)) == IOR
- && (rtx_equal_p (XEXP (XEXP (x, 0), 0), XEXP (x, 1))
- || rtx_equal_p (XEXP (XEXP (x, 0), 1), XEXP (x, 1)))
- && ! side_effects_p (XEXP (XEXP (x, 0), 0))
- && ! side_effects_p (XEXP (XEXP (x, 0), 1)))
- return XEXP (x, 1);
-
- /* Convert (A ^ B) & A to A & (~ B) since the latter is often a single
- insn (and may simplify more). */
- else if (GET_CODE (XEXP (x, 0)) == XOR
- && rtx_equal_p (XEXP (XEXP (x, 0), 0), XEXP (x, 1))
- && ! side_effects_p (XEXP (x, 1)))
- {
- x = gen_binary (AND, mode,
- gen_unary (NOT, mode, XEXP (XEXP (x, 0), 1)),
- XEXP (x, 1));
- goto restart;
- }
- else if (GET_CODE (XEXP (x, 0)) == XOR
- && rtx_equal_p (XEXP (XEXP (x, 0), 1), XEXP (x, 1))
- && ! side_effects_p (XEXP (x, 1)))
- {
- x = gen_binary (AND, mode,
- gen_unary (NOT, mode, XEXP (XEXP (x, 0), 0)),
- XEXP (x, 1));
- goto restart;
- }
-
- /* Similarly for (~ (A ^ B)) & A. */
- else if (GET_CODE (XEXP (x, 0)) == NOT
- && GET_CODE (XEXP (XEXP (x, 0), 0)) == XOR
- && rtx_equal_p (XEXP (XEXP (XEXP (x, 0), 0), 0), XEXP (x, 1))
- && ! side_effects_p (XEXP (x, 1)))
- {
- x = gen_binary (AND, mode, XEXP (XEXP (XEXP (x, 0), 0), 1),
- XEXP (x, 1));
- goto restart;
- }
- else if (GET_CODE (XEXP (x, 0)) == NOT
- && GET_CODE (XEXP (XEXP (x, 0), 0)) == XOR
- && rtx_equal_p (XEXP (XEXP (XEXP (x, 0), 0), 1), XEXP (x, 1))
- && ! side_effects_p (XEXP (x, 1)))
- {
- x = gen_binary (AND, mode, XEXP (XEXP (XEXP (x, 0), 0), 0),
- XEXP (x, 1));
- goto restart;
- }
+ if (GET_CODE (op0) == IOR
+ && (rtx_equal_p (XEXP (op0, 0), op1)
+ || rtx_equal_p (XEXP (op0, 1), op1))
+ && ! side_effects_p (XEXP (op0, 0))
+ && ! side_effects_p (XEXP (op0, 1)))
+ return op1;
/* In the following group of tests (and those in case IOR below),
we start with some combination of logical operations and apply
For example, (and (ior A B) (not B)) can occur as the result of
expanding a bit field assignment. When we apply the distributive
law to this, we get (ior (and (A (not B))) (and (B (not B)))),
- which then simplifies to (and (A (not B))). */
+ which then simplifies to (and (A (not B))).
- /* If we have (and (ior A B) C), apply the distributive law and then
+ If we have (and (ior A B) C), apply the distributive law and then
the inverse distributive law to see if things simplify. */
- if (GET_CODE (XEXP (x, 0)) == IOR || GET_CODE (XEXP (x, 0)) == XOR)
+ if (GET_CODE (op0) == IOR || GET_CODE (op0) == XOR)
{
x = apply_distributive_law
- (gen_binary (GET_CODE (XEXP (x, 0)), mode,
- gen_binary (AND, mode,
- XEXP (XEXP (x, 0), 0), XEXP (x, 1)),
- gen_binary (AND, mode,
- XEXP (XEXP (x, 0), 1), XEXP (x, 1))));
+ (gen_binary (GET_CODE (op0), mode,
+ gen_binary (AND, mode, XEXP (op0, 0), op1),
+ gen_binary (AND, mode, XEXP (op0, 1), op1)));
if (GET_CODE (x) != AND)
- goto restart;
+ return x;
}
- if (GET_CODE (XEXP (x, 1)) == IOR || GET_CODE (XEXP (x, 1)) == XOR)
- {
- x = apply_distributive_law
- (gen_binary (GET_CODE (XEXP (x, 1)), mode,
- gen_binary (AND, mode,
- XEXP (XEXP (x, 1), 0), XEXP (x, 0)),
- gen_binary (AND, mode,
- XEXP (XEXP (x, 1), 1), XEXP (x, 0))));
- if (GET_CODE (x) != AND)
- goto restart;
- }
+ if (GET_CODE (op1) == IOR || GET_CODE (op1) == XOR)
+ return apply_distributive_law
+ (gen_binary (GET_CODE (op1), mode,
+ gen_binary (AND, mode, XEXP (op1, 0), op0),
+ gen_binary (AND, mode, XEXP (op1, 1), op0)));
/* Similarly, taking advantage of the fact that
(and (not A) (xor B C)) == (xor (ior A B) (ior A C)) */
- if (GET_CODE (XEXP (x, 0)) == NOT && GET_CODE (XEXP (x, 1)) == XOR)
- {
- x = apply_distributive_law
- (gen_binary (XOR, mode,
- gen_binary (IOR, mode, XEXP (XEXP (x, 0), 0),
- XEXP (XEXP (x, 1), 0)),
- gen_binary (IOR, mode, XEXP (XEXP (x, 0), 0),
- XEXP (XEXP (x, 1), 1))));
- if (GET_CODE (x) != AND)
- goto restart;
- }
+ if (GET_CODE (op0) == NOT && GET_CODE (op1) == XOR)
+ return apply_distributive_law
+ (gen_binary (XOR, mode,
+ gen_binary (IOR, mode, XEXP (op0, 0), XEXP (op1, 0)),
+ gen_binary (IOR, mode, XEXP (op0, 0), XEXP (op1, 1))));
- else if (GET_CODE (XEXP (x, 1)) == NOT && GET_CODE (XEXP (x, 0)) == XOR)
- {
- x = apply_distributive_law
- (gen_binary (XOR, mode,
- gen_binary (IOR, mode, XEXP (XEXP (x, 1), 0),
- XEXP (XEXP (x, 0), 0)),
- gen_binary (IOR, mode, XEXP (XEXP (x, 1), 0),
- XEXP (XEXP (x, 0), 1))));
- if (GET_CODE (x) != AND)
- goto restart;
- }
+ else if (GET_CODE (op1) == NOT && GET_CODE (op0) == XOR)
+ return apply_distributive_law
+ (gen_binary (XOR, mode,
+ gen_binary (IOR, mode, XEXP (op1, 0), XEXP (op0, 0)),
+ gen_binary (IOR, mode, XEXP (op1, 0), XEXP (op0, 1))));
break;
case IOR:
/* (ior A C) is C if all bits of A that might be nonzero are on in C. */
- if (GET_CODE (XEXP (x, 1)) == CONST_INT
+ if (GET_CODE (op1) == CONST_INT
&& GET_MODE_BITSIZE (mode) <= HOST_BITS_PER_WIDE_INT
- && (nonzero_bits (XEXP (x, 0), mode) & ~ INTVAL (XEXP (x, 1))) == 0)
- return XEXP (x, 1);
+ && (nonzero_bits (op0, mode) & ~ INTVAL (op1)) == 0)
+ return op1;
/* Convert (A & B) | A to A. */
- if (GET_CODE (XEXP (x, 0)) == AND
- && (rtx_equal_p (XEXP (XEXP (x, 0), 0), XEXP (x, 1))
- || rtx_equal_p (XEXP (XEXP (x, 0), 1), XEXP (x, 1)))
- && ! side_effects_p (XEXP (XEXP (x, 0), 0))
- && ! side_effects_p (XEXP (XEXP (x, 0), 1)))
- return XEXP (x, 1);
+ if (GET_CODE (op0) == AND
+ && (rtx_equal_p (XEXP (op0, 0), op1)
+ || rtx_equal_p (XEXP (op0, 1), op1))
+ && ! side_effects_p (XEXP (op0, 0))
+ && ! side_effects_p (XEXP (op0, 1)))
+ return op1;
/* If we have (ior (and A B) C), apply the distributive law and then
the inverse distributive law to see if things simplify. */
- if (GET_CODE (XEXP (x, 0)) == AND)
+ if (GET_CODE (op0) == AND)
{
x = apply_distributive_law
(gen_binary (AND, mode,
- gen_binary (IOR, mode,
- XEXP (XEXP (x, 0), 0), XEXP (x, 1)),
- gen_binary (IOR, mode,
- XEXP (XEXP (x, 0), 1), XEXP (x, 1))));
+ gen_binary (IOR, mode, XEXP (op0, 0), op1),
+ gen_binary (IOR, mode, XEXP (op0, 1), op1)));
if (GET_CODE (x) != IOR)
- goto restart;
+ return x;
}
- if (GET_CODE (XEXP (x, 1)) == AND)
+ if (GET_CODE (op1) == AND)
{
x = apply_distributive_law
(gen_binary (AND, mode,
- gen_binary (IOR, mode,
- XEXP (XEXP (x, 1), 0), XEXP (x, 0)),
- gen_binary (IOR, mode,
- XEXP (XEXP (x, 1), 1), XEXP (x, 0))));
+ gen_binary (IOR, mode, XEXP (op1, 0), op0),
+ gen_binary (IOR, mode, XEXP (op1, 1), op0)));
if (GET_CODE (x) != IOR)
- goto restart;
+ return x;
}
/* Convert (ior (ashift A CX) (lshiftrt A CY)) where CX+CY equals the
mode size to (rotate A CX). */
- if (((GET_CODE (XEXP (x, 0)) == ASHIFT
- && GET_CODE (XEXP (x, 1)) == LSHIFTRT)
- || (GET_CODE (XEXP (x, 1)) == ASHIFT
- && GET_CODE (XEXP (x, 0)) == LSHIFTRT))
- && rtx_equal_p (XEXP (XEXP (x, 0), 0), XEXP (XEXP (x, 1), 0))
- && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT
- && GET_CODE (XEXP (XEXP (x, 1), 1)) == CONST_INT
- && (INTVAL (XEXP (XEXP (x, 0), 1)) + INTVAL (XEXP (XEXP (x, 1), 1))
+ if (((GET_CODE (op0) == ASHIFT && GET_CODE (op1) == LSHIFTRT)
+ || (GET_CODE (op1) == ASHIFT && GET_CODE (op0) == LSHIFTRT))
+ && rtx_equal_p (XEXP (op0, 0), XEXP (op1, 0))
+ && GET_CODE (XEXP (op0, 1)) == CONST_INT
+ && GET_CODE (XEXP (op1, 1)) == CONST_INT
+ && (INTVAL (XEXP (op0, 1)) + INTVAL (XEXP (op1, 1))
== GET_MODE_BITSIZE (mode)))
- {
- rtx shift_count;
+ return gen_rtx (ROTATE, mode, XEXP (op0, 0),
+ (GET_CODE (op0) == ASHIFT
+ ? XEXP (op0, 1) : XEXP (op1, 1)));
- if (GET_CODE (XEXP (x, 0)) == ASHIFT)
- shift_count = XEXP (XEXP (x, 0), 1);
- else
- shift_count = XEXP (XEXP (x, 1), 1);
- x = gen_rtx (ROTATE, mode, XEXP (XEXP (x, 0), 0), shift_count);
- goto restart;
- }
break;
case XOR:
(NOT y). */
{
int num_negated = 0;
- rtx in1 = XEXP (x, 0), in2 = XEXP (x, 1);
- if (GET_CODE (in1) == NOT)
- num_negated++, in1 = XEXP (in1, 0);
- if (GET_CODE (in2) == NOT)
- num_negated++, in2 = XEXP (in2, 0);
+ if (GET_CODE (op0) == NOT)
+ num_negated++, op0 = XEXP (op0, 0);
+ if (GET_CODE (op1) == NOT)
+ num_negated++, op1 = XEXP (op1, 0);
if (num_negated == 2)
{
- SUBST (XEXP (x, 0), XEXP (XEXP (x, 0), 0));
- SUBST (XEXP (x, 1), XEXP (XEXP (x, 1), 0));
+ SUBST (XEXP (x, 0), op0);
+ SUBST (XEXP (x, 1), op1);
}
else if (num_negated == 1)
- {
- x = gen_unary (NOT, mode,
- gen_binary (XOR, mode, in1, in2));
- goto restart;
- }
+ return gen_unary (NOT, mode, gen_binary (XOR, mode, op0, op1));
}
/* Convert (xor (and A B) B) to (and (not A) B). The latter may
correspond to a machine insn or result in further simplifications
if B is a constant. */
- if (GET_CODE (XEXP (x, 0)) == AND
- && rtx_equal_p (XEXP (XEXP (x, 0), 1), XEXP (x, 1))
- && ! side_effects_p (XEXP (x, 1)))
- {
- x = gen_binary (AND, mode,
- gen_unary (NOT, mode, XEXP (XEXP (x, 0), 0)),
- XEXP (x, 1));
- goto restart;
- }
- else if (GET_CODE (XEXP (x, 0)) == AND
- && rtx_equal_p (XEXP (XEXP (x, 0), 0), XEXP (x, 1))
- && ! side_effects_p (XEXP (x, 1)))
- {
- x = gen_binary (AND, mode,
- gen_unary (NOT, mode, XEXP (XEXP (x, 0), 1)),
- XEXP (x, 1));
- goto restart;
- }
+ if (GET_CODE (op0) == AND
+ && rtx_equal_p (XEXP (op0, 1), op1)
+ && ! side_effects_p (op1))
+ return gen_binary (AND, mode, gen_unary (NOT, mode, XEXP (op0, 0)),
+ op1);
+ else if (GET_CODE (op0) == AND
+ && rtx_equal_p (XEXP (op0, 0), op1)
+ && ! side_effects_p (op1))
+ return gen_binary (AND, mode, gen_unary (NOT, mode, XEXP (op0, 1)),
+ op1);
#if STORE_FLAG_VALUE == 1
/* (xor (comparison foo bar) (const_int 1)) can become the reversed
comparison. */
- if (XEXP (x, 1) == const1_rtx
- && GET_RTX_CLASS (GET_CODE (XEXP (x, 0))) == '<'
- && reversible_comparison_p (XEXP (x, 0)))
- return gen_rtx_combine (reverse_condition (GET_CODE (XEXP (x, 0))),
- mode, XEXP (XEXP (x, 0), 0),
- XEXP (XEXP (x, 0), 1));
+ if (op1 == const1_rtx
+ && GET_RTX_CLASS (GET_CODE (op0)) == '<'
+ && reversible_comparison_p (op0))
+ return gen_rtx_combine (reverse_condition (GET_CODE (op0)),
+ mode, XEXP (op0, 0), XEXP (op0, 1));
/* (lshiftrt foo C) where C is the number of bits in FOO minus 1
is (lt foo (const_int 0)), so we can perform the above
simplification. */
- if (XEXP (x, 1) == const1_rtx
- && GET_CODE (XEXP (x, 0)) == LSHIFTRT
- && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT
- && INTVAL (XEXP (XEXP (x, 0), 1)) == GET_MODE_BITSIZE (mode) - 1)
- return gen_rtx_combine (GE, mode, XEXP (XEXP (x, 0), 0), const0_rtx);
+ if (op1 == const1_rtx
+ && GET_CODE (op0) == LSHIFTRT
+ && GET_CODE (XEXP (op0, 1)) == CONST_INT
+ && INTVAL (XEXP (op0, 1)) == GET_MODE_BITSIZE (mode) - 1)
+ return gen_rtx_combine (GE, mode, XEXP (op0, 0), const0_rtx);
#endif
/* (xor (comparison foo bar) (const_int sign-bit))
if (GET_MODE_BITSIZE (mode) <= HOST_BITS_PER_WIDE_INT
&& (STORE_FLAG_VALUE
== (HOST_WIDE_INT) 1 << (GET_MODE_BITSIZE (mode) - 1))
- && XEXP (x, 1) == const_true_rtx
- && GET_RTX_CLASS (GET_CODE (XEXP (x, 0))) == '<'
- && reversible_comparison_p (XEXP (x, 0)))
- return gen_rtx_combine (reverse_condition (GET_CODE (XEXP (x, 0))),
- mode, XEXP (XEXP (x, 0), 0),
- XEXP (XEXP (x, 0), 1));
- break;
-
- case ABS:
- /* (abs (neg <foo>)) -> (abs <foo>) */
- if (GET_CODE (XEXP (x, 0)) == NEG)
- SUBST (XEXP (x, 0), XEXP (XEXP (x, 0), 0));
-
- /* If operand is something known to be positive, ignore the ABS. */
- if (GET_CODE (XEXP (x, 0)) == FFS || GET_CODE (XEXP (x, 0)) == ABS
- || ((GET_MODE_BITSIZE (GET_MODE (XEXP (x, 0)))
- <= HOST_BITS_PER_WIDE_INT)
- && ((nonzero_bits (XEXP (x, 0), GET_MODE (XEXP (x, 0)))
- & ((HOST_WIDE_INT) 1
- << (GET_MODE_BITSIZE (GET_MODE (XEXP (x, 0))) - 1)))
- == 0)))
- return XEXP (x, 0);
-
-
- /* If operand is known to be only -1 or 0, convert ABS to NEG. */
- if (num_sign_bit_copies (XEXP (x, 0), mode) == GET_MODE_BITSIZE (mode))
- {
- x = gen_rtx_combine (NEG, mode, XEXP (x, 0));
- goto restart;
- }
- break;
-
- case FFS:
- /* (ffs (*_extend <X>)) = (ffs <X>) */
- if (GET_CODE (XEXP (x, 0)) == SIGN_EXTEND
- || GET_CODE (XEXP (x, 0)) == ZERO_EXTEND)
- SUBST (XEXP (x, 0), XEXP (XEXP (x, 0), 0));
- break;
-
- case FLOAT:
- /* (float (sign_extend <X>)) = (float <X>). */
- if (GET_CODE (XEXP (x, 0)) == SIGN_EXTEND)
- SUBST (XEXP (x, 0), XEXP (XEXP (x, 0), 0));
- break;
-
- case LSHIFT:
- case ASHIFT:
- case LSHIFTRT:
- case ASHIFTRT:
- case ROTATE:
- case ROTATERT:
- /* If this is a shift by a constant amount, simplify it. */
- if (GET_CODE (XEXP (x, 1)) == CONST_INT)
- {
- x = simplify_shift_const (x, code, mode, XEXP (x, 0),
- INTVAL (XEXP (x, 1)));
- if (GET_CODE (x) != code)
- goto restart;
- }
-
-#ifdef SHIFT_COUNT_TRUNCATED
- else if (SHIFT_COUNT_TRUNCATED && GET_CODE (XEXP (x, 1)) != REG)
- SUBST (XEXP (x, 1),
- force_to_mode (XEXP (x, 1), GET_MODE (x),
- ((HOST_WIDE_INT) 1
- << exact_log2 (GET_MODE_BITSIZE (GET_MODE (x))))
- - 1,
- NULL_RTX, 0));
-#endif
-
+ && op1 == const_true_rtx
+ && GET_RTX_CLASS (GET_CODE (op0)) == '<'
+ && reversible_comparison_p (op0))
+ return gen_rtx_combine (reverse_condition (GET_CODE (op0)),
+ mode, XEXP (op0, 0), XEXP (op0, 1));
break;
}
if (GET_CODE (XEXP (x, 0)) == CONST_INT)
return x;
- if (! FAKE_EXTEND_SAFE_P (GET_MODE (XEXP (x, 0)), XEXP (x, 0)))
+ /* Return if (subreg:MODE FROM 0) is not a safe replacement for
+ (zero_extend:MODE FROM) or (sign_extend:MODE FROM). It is for any MEM
+ because (SUBREG (MEM...)) is guaranteed to cause the MEM to be
+ reloaded. If not for that, MEM's would very rarely be safe.
+
+ Reject MODEs bigger than a word, because we might not be able
+ to reference a two-register group starting with an arbitrary register
+ (and currently gen_lowpart might crash for a SUBREG). */
+
+ if (GET_MODE_SIZE (GET_MODE (XEXP (x, 0))) > UNITS_PER_WORD)
return x;
len = GET_MODE_BITSIZE (GET_MODE (XEXP (x, 0)));
git://gcc.gnu.org / gcc.git / commitdiff