/* Fold a constant sub-tree into a single node for C-compiler
- Copyright (C) 1987, 1988, 1992, 1993 Free Software Foundation, Inc.
+ Copyright (C) 1987, 88, 92, 93, 94, 95, 1996 Free Software Foundation, Inc.
This file is part of GNU CC.
You should have received a copy of the GNU General Public License
along with GNU CC; see the file COPYING. If not, write to
-the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
-
-/*@@ Fix lossage on folding division of big integers. */
+the Free Software Foundation, 59 Temple Place - Suite 330,
+Boston, MA 02111-1307, USA. */
/*@@ This file should be rewritten to use an arbitrary precision
@@ representation for "struct tree_int_cst" and "struct tree_real_cst".
/* Handle floating overflow for `const_binop'. */
static jmp_buf float_error;
-static void encode PROTO((short *, HOST_WIDE_INT, HOST_WIDE_INT));
-static void decode PROTO((short *, HOST_WIDE_INT *, HOST_WIDE_INT *));
-static int div_and_round_double PROTO((enum tree_code, int, HOST_WIDE_INT,
+static void encode PROTO((HOST_WIDE_INT *, HOST_WIDE_INT, HOST_WIDE_INT));
+static void decode PROTO((HOST_WIDE_INT *, HOST_WIDE_INT *, HOST_WIDE_INT *));
+int div_and_round_double PROTO((enum tree_code, int, HOST_WIDE_INT,
HOST_WIDE_INT, HOST_WIDE_INT,
HOST_WIDE_INT, HOST_WIDE_INT *,
HOST_WIDE_INT *, HOST_WIDE_INT *,
static tree fold_convert PROTO((tree, tree));
static enum tree_code invert_tree_comparison PROTO((enum tree_code));
static enum tree_code swap_tree_comparison PROTO((enum tree_code));
+static int truth_value_p PROTO((enum tree_code));
static int operand_equal_for_comparison_p PROTO((tree, tree, tree));
-static int twoval_comparison_p PROTO((tree, tree *, tree *));
+static int twoval_comparison_p PROTO((tree, tree *, tree *, int *));
static tree eval_subst PROTO((tree, tree, tree, tree, tree));
static tree omit_one_operand PROTO((tree, tree, tree));
+static tree pedantic_omit_one_operand PROTO((tree, tree, tree));
static tree distribute_bit_expr PROTO((enum tree_code, tree, tree, tree));
static tree make_bit_field_ref PROTO((tree, tree, int, int, int));
static tree optimize_bit_field_compare PROTO((enum tree_code, tree,
tree, tree));
static tree decode_field_reference PROTO((tree, int *, int *,
enum machine_mode *, int *,
- int *, tree *));
+ int *, tree *, tree *));
static int all_ones_mask_p PROTO((tree, int));
static int simple_operand_p PROTO((tree));
static tree range_test PROTO((enum tree_code, tree, enum tree_code,
enum tree_code, tree, tree, tree));
+static tree unextend PROTO((tree, int, int, tree));
static tree fold_truthop PROTO((enum tree_code, tree, tree, tree));
+static tree strip_compound_expr PROTO((tree, tree));
#ifndef BRANCH_COST
#define BRANCH_COST 1
#endif
-/* Yield nonzero if a signed left shift of A by B bits overflows. */
-#define left_shift_overflows(a, b) ((a) != ((a) << (b)) >> (b))
-
/* Suppose A1 + B1 = SUM1, using 2's complement arithmetic ignoring overflow.
Suppose A, B and SUM have the same respective signs as A1, B1, and SUM1.
Then this yields nonzero if overflow occurred during the addition.
#define overflow_sum_sign(a, b, sum) ((~((a) ^ (b)) & ((a) ^ (sum))) < 0)
\f
/* To do constant folding on INTEGER_CST nodes requires two-word arithmetic.
- We do that by representing the two-word integer as MAX_SHORTS shorts,
- with only 8 bits stored in each short, as a positive number. */
+ We do that by representing the two-word integer in 4 words, with only
+ HOST_BITS_PER_WIDE_INT/2 bits stored in each word, as a positive number. */
+
+#define LOWPART(x) \
+ ((x) & (((unsigned HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT/2)) - 1))
+#define HIGHPART(x) \
+ ((unsigned HOST_WIDE_INT) (x) >> HOST_BITS_PER_WIDE_INT/2)
+#define BASE ((unsigned HOST_WIDE_INT) 1 << HOST_BITS_PER_WIDE_INT/2)
-/* Unpack a two-word integer into MAX_SHORTS shorts.
+/* Unpack a two-word integer into 4 words.
LOW and HI are the integer, as two `HOST_WIDE_INT' pieces.
- SHORTS points to the array of shorts. */
+ WORDS points to the array of HOST_WIDE_INTs. */
static void
-encode (shorts, low, hi)
- short *shorts;
+encode (words, low, hi)
+ HOST_WIDE_INT *words;
HOST_WIDE_INT low, hi;
{
- register int i;
-
- for (i = 0; i < MAX_SHORTS / 2; i++)
- {
- shorts[i] = (low >> (i * 8)) & 0xff;
- shorts[i + MAX_SHORTS / 2] = (hi >> (i * 8) & 0xff);
- }
+ words[0] = LOWPART (low);
+ words[1] = HIGHPART (low);
+ words[2] = LOWPART (hi);
+ words[3] = HIGHPART (hi);
}
-/* Pack an array of MAX_SHORTS shorts into a two-word integer.
- SHORTS points to the array of shorts.
+/* Pack an array of 4 words into a two-word integer.
+ WORDS points to the array of words.
The integer is stored into *LOW and *HI as two `HOST_WIDE_INT' pieces. */
static void
-decode (shorts, low, hi)
- short *shorts;
+decode (words, low, hi)
+ HOST_WIDE_INT *words;
HOST_WIDE_INT *low, *hi;
{
- register int i;
- HOST_WIDE_INT lv = 0, hv = 0;
-
- for (i = 0; i < MAX_SHORTS / 2; i++)
- {
- lv |= (HOST_WIDE_INT) shorts[i] << (i * 8);
- hv |= (HOST_WIDE_INT) shorts[i + MAX_SHORTS / 2] << (i * 8);
- }
-
- *low = lv, *hi = hv;
+ *low = words[0] | words[1] * BASE;
+ *hi = words[2] | words[3] * BASE;
}
\f
/* Make the integer constant T valid for its type
that don't belong in the type.
Yield 1 if a signed overflow occurs, 0 otherwise.
If OVERFLOW is nonzero, a signed overflow has already occurred
- in calculating T, so propagate it. */
+ in calculating T, so propagate it.
+
+ Make the real constant T valid for its type by calling CHECK_FLOAT_VALUE,
+ if it exists. */
int
force_fit_type (t, overflow)
HOST_WIDE_INT low, high;
register int prec;
- if (TREE_CODE (t) != INTEGER_CST)
+ if (TREE_CODE (t) == REAL_CST)
+ {
+#ifdef CHECK_FLOAT_VALUE
+ CHECK_FLOAT_VALUE (TYPE_MODE (TREE_TYPE (t)), TREE_REAL_CST (t),
+ overflow);
+#endif
+ return overflow;
+ }
+
+ else if (TREE_CODE (t) != INTEGER_CST)
return overflow;
low = TREE_INT_CST_LOW (t);
/* Unsigned types do not suffer sign extension or overflow. */
if (TREE_UNSIGNED (TREE_TYPE (t)))
- return 0;
+ return overflow;
/* If the value's sign bit is set, extend the sign. */
if (prec != 2 * HOST_BITS_PER_WIDE_INT
/* Add two doubleword integers with doubleword result.
Each argument is given as two `HOST_WIDE_INT' pieces.
One argument is L1 and H1; the other, L2 and H2.
- The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV.
- We use the 8-shorts representation internally. */
+ The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */
int
add_double (l1, h1, l2, h2, lv, hv)
HOST_WIDE_INT l1, h1, l2, h2;
HOST_WIDE_INT *lv, *hv;
{
- short arg1[MAX_SHORTS];
- short arg2[MAX_SHORTS];
- register int carry = 0;
- register int i;
+ HOST_WIDE_INT l, h;
- encode (arg1, l1, h1);
- encode (arg2, l2, h2);
-
- for (i = 0; i < MAX_SHORTS; i++)
- {
- carry += arg1[i] + arg2[i];
- arg1[i] = carry & 0xff;
- carry >>= 8;
- }
+ l = l1 + l2;
+ h = h1 + h2 + ((unsigned HOST_WIDE_INT) l < l1);
- decode (arg1, lv, hv);
- return overflow_sum_sign (h1, h2, *hv);
+ *lv = l;
+ *hv = h;
+ return overflow_sum_sign (h1, h2, h);
}
/* Negate a doubleword integer with doubleword result.
Return nonzero if the operation overflows, assuming it's signed.
The argument is given as two `HOST_WIDE_INT' pieces in L1 and H1.
- The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV.
- We use the 8-shorts representation internally. */
+ The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */
int
neg_double (l1, h1, lv, hv)
Return nonzero if the operation overflows, assuming it's signed.
Each argument is given as two `HOST_WIDE_INT' pieces.
One argument is L1 and H1; the other, L2 and H2.
- The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV.
- We use the 8-shorts representation internally. */
+ The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */
int
mul_double (l1, h1, l2, h2, lv, hv)
HOST_WIDE_INT l1, h1, l2, h2;
HOST_WIDE_INT *lv, *hv;
{
- short arg1[MAX_SHORTS];
- short arg2[MAX_SHORTS];
- short prod[MAX_SHORTS * 2];
- register int carry = 0;
+ HOST_WIDE_INT arg1[4];
+ HOST_WIDE_INT arg2[4];
+ HOST_WIDE_INT prod[4 * 2];
+ register unsigned HOST_WIDE_INT carry;
register int i, j, k;
HOST_WIDE_INT toplow, tophigh, neglow, neghigh;
- /* These cases are used extensively, arising from pointer combinations. */
- if (h2 == 0)
- {
- if (l2 == 2)
- {
- int overflow = left_shift_overflows (h1, 1);
- unsigned HOST_WIDE_INT temp = l1 + l1;
- *hv = (h1 << 1) + (temp < l1);
- *lv = temp;
- return overflow;
- }
- if (l2 == 4)
- {
- int overflow = left_shift_overflows (h1, 2);
- unsigned HOST_WIDE_INT temp = l1 + l1;
- h1 = (h1 << 2) + ((temp < l1) << 1);
- l1 = temp;
- temp += temp;
- h1 += (temp < l1);
- *lv = temp;
- *hv = h1;
- return overflow;
- }
- if (l2 == 8)
- {
- int overflow = left_shift_overflows (h1, 3);
- unsigned HOST_WIDE_INT temp = l1 + l1;
- h1 = (h1 << 3) + ((temp < l1) << 2);
- l1 = temp;
- temp += temp;
- h1 += (temp < l1) << 1;
- l1 = temp;
- temp += temp;
- h1 += (temp < l1);
- *lv = temp;
- *hv = h1;
- return overflow;
- }
- }
-
encode (arg1, l1, h1);
encode (arg2, l2, h2);
- bzero (prod, sizeof prod);
+ bzero ((char *) prod, sizeof prod);
- for (i = 0; i < MAX_SHORTS; i++)
- for (j = 0; j < MAX_SHORTS; j++)
- {
- k = i + j;
- carry = arg1[i] * arg2[j];
- while (carry)
- {
- carry += prod[k];
- prod[k] = carry & 0xff;
- carry >>= 8;
- k++;
- }
- }
+ for (i = 0; i < 4; i++)
+ {
+ carry = 0;
+ for (j = 0; j < 4; j++)
+ {
+ k = i + j;
+ /* This product is <= 0xFFFE0001, the sum <= 0xFFFF0000. */
+ carry += arg1[i] * arg2[j];
+ /* Since prod[p] < 0xFFFF, this sum <= 0xFFFFFFFF. */
+ carry += prod[k];
+ prod[k] = LOWPART (carry);
+ carry = HIGHPART (carry);
+ }
+ prod[i + 4] = carry;
+ }
- decode (prod, lv, hv); /* This ignores
- prod[MAX_SHORTS] -> prod[MAX_SHORTS*2-1] */
+ decode (prod, lv, hv); /* This ignores prod[4] through prod[4*2-1] */
/* Check for overflow by calculating the top half of the answer in full;
it should agree with the low half's sign bit. */
- decode (prod+MAX_SHORTS, &toplow, &tophigh);
+ decode (prod+4, &toplow, &tophigh);
if (h1 < 0)
{
neg_double (l2, h2, &neglow, &neghigh);
HOST_WIDE_INT *lv, *hv;
int arith;
{
- short arg1[MAX_SHORTS];
- register int i;
- register int carry;
-
if (count < 0)
{
rshift_double (l1, h1, - count, prec, lv, hv, arith);
return;
}
+
+#ifdef SHIFT_COUNT_TRUNCATED
+ if (SHIFT_COUNT_TRUNCATED)
+ count %= prec;
+#endif
- encode (arg1, l1, h1);
-
- if (count > prec)
- count = prec;
-
- while (count > 0)
+ if (count >= HOST_BITS_PER_WIDE_INT)
{
- carry = 0;
- for (i = 0; i < MAX_SHORTS; i++)
- {
- carry += arg1[i] << 1;
- arg1[i] = carry & 0xff;
- carry >>= 8;
- }
- count--;
+ *hv = (unsigned HOST_WIDE_INT) l1 << count - HOST_BITS_PER_WIDE_INT;
+ *lv = 0;
+ }
+ else
+ {
+ *hv = (((unsigned HOST_WIDE_INT) h1 << count)
+ | ((unsigned HOST_WIDE_INT) l1 >> HOST_BITS_PER_WIDE_INT - count - 1 >> 1));
+ *lv = (unsigned HOST_WIDE_INT) l1 << count;
}
-
- decode (arg1, lv, hv);
}
/* Shift the doubleword integer in L1, H1 right by COUNT places
HOST_WIDE_INT *lv, *hv;
int arith;
{
- short arg1[MAX_SHORTS];
- register int i;
- register int carry;
-
- encode (arg1, l1, h1);
-
- if (count > prec)
- count = prec;
+ unsigned HOST_WIDE_INT signmask;
+ signmask = (arith
+ ? -((unsigned HOST_WIDE_INT) h1 >> (HOST_BITS_PER_WIDE_INT - 1))
+ : 0);
+
+#ifdef SHIFT_COUNT_TRUNCATED
+ if (SHIFT_COUNT_TRUNCATED)
+ count %= prec;
+#endif
- while (count > 0)
+ if (count >= HOST_BITS_PER_WIDE_INT)
{
- carry = arith && arg1[7] >> 7;
- for (i = MAX_SHORTS - 1; i >= 0; i--)
- {
- carry <<= 8;
- carry += arg1[i];
- arg1[i] = (carry >> 1) & 0xff;
- }
- count--;
+ *hv = signmask;
+ *lv = ((signmask << 2 * HOST_BITS_PER_WIDE_INT - count - 1 << 1)
+ | ((unsigned HOST_WIDE_INT) h1 >> count - HOST_BITS_PER_WIDE_INT));
+ }
+ else
+ {
+ *lv = (((unsigned HOST_WIDE_INT) l1 >> count)
+ | ((unsigned HOST_WIDE_INT) h1 << HOST_BITS_PER_WIDE_INT - count - 1 << 1));
+ *hv = ((signmask << HOST_BITS_PER_WIDE_INT - count)
+ | ((unsigned HOST_WIDE_INT) h1 >> count));
}
-
- decode (arg1, lv, hv);
}
\f
-/* Rotate the doubldword integer in L1, H1 left by COUNT places
+/* Rotate the doubleword integer in L1, H1 left by COUNT places
keeping only PREC bits of result.
Rotate right if COUNT is negative.
Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */
int prec;
HOST_WIDE_INT *lv, *hv;
{
- short arg1[MAX_SHORTS];
- register int i;
- register int carry;
+ HOST_WIDE_INT s1l, s1h, s2l, s2h;
+ count %= prec;
if (count < 0)
- {
- rrotate_double (l1, h1, - count, prec, lv, hv);
- return;
- }
-
- encode (arg1, l1, h1);
-
- if (count > prec)
- count = prec;
+ count += prec;
- carry = arg1[MAX_SHORTS - 1] >> 7;
- while (count > 0)
- {
- for (i = 0; i < MAX_SHORTS; i++)
- {
- carry += arg1[i] << 1;
- arg1[i] = carry & 0xff;
- carry >>= 8;
- }
- count--;
- }
-
- decode (arg1, lv, hv);
+ lshift_double (l1, h1, count, prec, &s1l, &s1h, 0);
+ rshift_double (l1, h1, prec - count, prec, &s2l, &s2h, 0);
+ *lv = s1l | s2l;
+ *hv = s1h | s2h;
}
/* Rotate the doubleword integer in L1, H1 left by COUNT places
int prec;
HOST_WIDE_INT *lv, *hv;
{
- short arg1[MAX_SHORTS];
- register int i;
- register int carry;
-
- encode (arg1, l1, h1);
-
- if (count > prec)
- count = prec;
+ HOST_WIDE_INT s1l, s1h, s2l, s2h;
- carry = arg1[0] & 1;
- while (count > 0)
- {
- for (i = MAX_SHORTS - 1; i >= 0; i--)
- {
- carry <<= 8;
- carry += arg1[i];
- arg1[i] = (carry >> 1) & 0xff;
- }
- count--;
- }
+ count %= prec;
+ if (count < 0)
+ count += prec;
- decode (arg1, lv, hv);
+ rshift_double (l1, h1, count, prec, &s1l, &s1h, 0);
+ lshift_double (l1, h1, prec - count, prec, &s2l, &s2h, 0);
+ *lv = s1l | s2l;
+ *hv = s1h | s2h;
}
\f
/* Divide doubleword integer LNUM, HNUM by doubleword integer LDEN, HDEN
Return nonzero if the operation overflows.
UNS nonzero says do unsigned division. */
-static int
+int
div_and_round_double (code, uns,
lnum_orig, hnum_orig, lden_orig, hden_orig,
lquo, hquo, lrem, hrem)
HOST_WIDE_INT *lquo, *hquo, *lrem, *hrem;
{
int quo_neg = 0;
- short num[MAX_SHORTS + 1]; /* extra element for scaling. */
- short den[MAX_SHORTS], quo[MAX_SHORTS];
- register int i, j, work;
- register int carry = 0;
+ HOST_WIDE_INT num[4 + 1]; /* extra element for scaling. */
+ HOST_WIDE_INT den[4], quo[4];
+ register int i, j;
+ unsigned HOST_WIDE_INT work;
+ register unsigned HOST_WIDE_INT carry = 0;
HOST_WIDE_INT lnum = lnum_orig;
HOST_WIDE_INT hnum = hnum_orig;
HOST_WIDE_INT lden = lden_orig;
goto finish_up;
}
- bzero (quo, sizeof quo);
+ bzero ((char *) quo, sizeof quo);
- bzero (num, sizeof num); /* to zero 9th element */
- bzero (den, sizeof den);
+ bzero ((char *) num, sizeof num); /* to zero 9th element */
+ bzero ((char *) den, sizeof den);
encode (num, lnum, hnum);
encode (den, lden, hden);
- /* This code requires more than just hden == 0.
- We also have to require that we don't need more than three bytes
- to hold CARRY. If we ever did need four bytes to hold it, we
- would lose part of it when computing WORK on the next round. */
- if (hden == 0 && (((unsigned HOST_WIDE_INT) lden << 8) >> 8) == lden)
- { /* simpler algorithm */
+ /* Special code for when the divisor < BASE. */
+ if (hden == 0 && lden < BASE)
+ {
/* hnum != 0 already checked. */
- for (i = MAX_SHORTS - 1; i >= 0; i--)
+ for (i = 4 - 1; i >= 0; i--)
{
- work = num[i] + (carry << 8);
+ work = num[i] + carry * BASE;
quo[i] = work / (unsigned HOST_WIDE_INT) lden;
carry = work % (unsigned HOST_WIDE_INT) lden;
}
}
- else { /* full double precision,
- with thanks to Don Knuth's
- "Seminumerical Algorithms". */
-#define BASE 256
- int quo_est, scale, num_hi_sig, den_hi_sig, quo_hi_sig;
+ else
+ {
+ /* Full double precision division,
+ with thanks to Don Knuth's "Seminumerical Algorithms". */
+ int num_hi_sig, den_hi_sig;
+ unsigned HOST_WIDE_INT quo_est, scale;
/* Find the highest non-zero divisor digit. */
- for (i = MAX_SHORTS - 1; ; i--)
+ for (i = 4 - 1; ; i--)
if (den[i] != 0) {
den_hi_sig = i;
break;
}
- for (i = MAX_SHORTS - 1; ; i--)
- if (num[i] != 0) {
- num_hi_sig = i;
- break;
- }
- quo_hi_sig = num_hi_sig - den_hi_sig + 1;
/* Insure that the first digit of the divisor is at least BASE/2.
This is required by the quotient digit estimation algorithm. */
scale = BASE / (den[den_hi_sig] + 1);
if (scale > 1) { /* scale divisor and dividend */
carry = 0;
- for (i = 0; i <= MAX_SHORTS - 1; i++) {
+ for (i = 0; i <= 4 - 1; i++) {
work = (num[i] * scale) + carry;
- num[i] = work & 0xff;
- carry = work >> 8;
- if (num[i] != 0) num_hi_sig = i;
- }
+ num[i] = LOWPART (work);
+ carry = HIGHPART (work);
+ } num[4] = carry;
carry = 0;
- for (i = 0; i <= MAX_SHORTS - 1; i++) {
+ for (i = 0; i <= 4 - 1; i++) {
work = (den[i] * scale) + carry;
- den[i] = work & 0xff;
- carry = work >> 8;
+ den[i] = LOWPART (work);
+ carry = HIGHPART (work);
if (den[i] != 0) den_hi_sig = i;
}
}
+ num_hi_sig = 4;
+
/* Main loop */
- for (i = quo_hi_sig; i > 0; i--) {
+ for (i = num_hi_sig - den_hi_sig - 1; i >= 0; i--) {
/* guess the next quotient digit, quo_est, by dividing the first
two remaining dividend digits by the high order quotient digit.
quo_est is never low and is at most 2 high. */
+ unsigned HOST_WIDE_INT tmp;
- int num_hi; /* index of highest remaining dividend digit */
-
- num_hi = i + den_hi_sig;
-
- work = (num[num_hi] * BASE) + (num_hi > 0 ? num[num_hi - 1] : 0);
- if (num[num_hi] != den[den_hi_sig]) {
+ num_hi_sig = i + den_hi_sig + 1;
+ work = num[num_hi_sig] * BASE + num[num_hi_sig - 1];
+ if (num[num_hi_sig] != den[den_hi_sig])
quo_est = work / den[den_hi_sig];
- }
- else {
+ else
quo_est = BASE - 1;
- }
/* refine quo_est so it's usually correct, and at most one high. */
- while ((den[den_hi_sig - 1] * quo_est)
- > (((work - (quo_est * den[den_hi_sig])) * BASE)
- + ((num_hi - 1) > 0 ? num[num_hi - 2] : 0)))
+ tmp = work - quo_est * den[den_hi_sig];
+ if (tmp < BASE
+ && den[den_hi_sig - 1] * quo_est > (tmp * BASE + num[num_hi_sig - 2]))
quo_est--;
/* Try QUO_EST as the quotient digit, by multiplying the
Keep in mind that QUO_EST is the I - 1st digit. */
carry = 0;
-
for (j = 0; j <= den_hi_sig; j++)
{
- int digit;
-
- work = num[i + j - 1] - (quo_est * den[j]) + carry;
- digit = work & 0xff;
- carry = work >> 8;
- if (digit < 0)
- {
- digit += BASE;
- carry--;
- }
- num[i + j - 1] = digit;
+ work = quo_est * den[j] + carry;
+ carry = HIGHPART (work);
+ work = num[i + j] - LOWPART (work);
+ num[i + j] = LOWPART (work);
+ carry += HIGHPART (work) != 0;
}
/* if quo_est was high by one, then num[i] went negative and
we need to correct things. */
- if (num[num_hi] < 0)
+ if (num[num_hi_sig] < carry)
{
quo_est--;
carry = 0; /* add divisor back in */
for (j = 0; j <= den_hi_sig; j++)
{
- work = num[i + j - 1] + den[j] + carry;
- if (work > BASE)
- {
- work -= BASE;
- carry = 1;
- }
- else
- {
- carry = 0;
- }
- num[i + j - 1] = work;
+ work = num[i + j] + den[j] + carry;
+ carry = HIGHPART (work);
+ num[i + j] = LOWPART (work);
}
- num [num_hi] += carry;
+ num [num_hi_sig] += carry;
}
/* store the quotient digit. */
- quo[i - 1] = quo_est;
+ quo[i] = quo_est;
}
}
}
\f
#ifndef REAL_ARITHMETIC
-/* Effectively truncate a real value to represent
- the nearest possible value in a narrower mode.
- The result is actually represented in the same data type as the argument,
- but its value is usually different. */
+/* Effectively truncate a real value to represent the nearest possible value
+ in a narrower mode. The result is actually represented in the same data
+ type as the argument, but its value is usually different.
+
+ A trap may occur during the FP operations and it is the responsibility
+ of the calling function to have a handler established. */
REAL_VALUE_TYPE
real_value_truncate (mode, arg)
enum machine_mode mode;
REAL_VALUE_TYPE arg;
{
-#ifdef __STDC__
- /* Make sure the value is actually stored in memory before we turn off
- the handler. */
- volatile
-#endif
- REAL_VALUE_TYPE value;
- jmp_buf handler, old_handler;
- int handled;
-
- if (setjmp (handler))
- {
- error ("floating overflow");
- return dconst0;
- }
- handled = push_float_handler (handler, old_handler);
- value = REAL_VALUE_TRUNCATE (mode, arg);
- pop_float_handler (handled, old_handler);
- return value;
+ return REAL_VALUE_TRUNCATE (mode, arg);
}
#if TARGET_FLOAT_FORMAT == IEEE_FLOAT_FORMAT
register tree arg1, arg2;
int notrunc;
{
+ STRIP_NOPS (arg1); STRIP_NOPS (arg2);
+
if (TREE_CODE (arg1) == INTEGER_CST)
{
register HOST_WIDE_INT int1l = TREE_INT_CST_LOW (arg1);
break;
case MULT_EXPR:
- /* Optimize simple cases. */
- if (int1h == 0)
- {
- unsigned HOST_WIDE_INT temp;
-
- switch (int1l)
- {
- case 0:
- t = build_int_2 (0, 0);
- goto got_it;
- case 1:
- t = build_int_2 (int2l, int2h);
- goto got_it;
- case 2:
- overflow = left_shift_overflows (int2h, 1);
- temp = int2l + int2l;
- int2h = (int2h << 1) + (temp < int2l);
- t = build_int_2 (temp, int2h);
- goto got_it;
-#if 0 /* This code can lose carries. */
- case 3:
- temp = int2l + int2l + int2l;
- int2h = int2h * 3 + (temp < int2l);
- t = build_int_2 (temp, int2h);
- goto got_it;
-#endif
- case 4:
- overflow = left_shift_overflows (int2h, 2);
- temp = int2l + int2l;
- int2h = (int2h << 2) + ((temp < int2l) << 1);
- int2l = temp;
- temp += temp;
- int2h += (temp < int2l);
- t = build_int_2 (temp, int2h);
- goto got_it;
- case 8:
- overflow = left_shift_overflows (int2h, 3);
- temp = int2l + int2l;
- int2h = (int2h << 3) + ((temp < int2l) << 2);
- int2l = temp;
- temp += temp;
- int2h += (temp < int2l) << 1;
- int2l = temp;
- temp += temp;
- int2h += (temp < int2l);
- t = build_int_2 (temp, int2h);
- goto got_it;
- default:
- break;
- }
- }
-
- if (int2h == 0)
- {
- if (int2l == 0)
- {
- t = build_int_2 (0, 0);
- break;
- }
- if (int2l == 1)
- {
- t = build_int_2 (int1l, int1h);
- break;
- }
- }
-
overflow = mul_double (int1l, int1h, int2l, int2h, &low, &hi);
t = build_int_2 (low, hi);
break;
got_it:
TREE_TYPE (t) = TREE_TYPE (arg1);
TREE_OVERFLOW (t)
- = ((notrunc ? !uns && overflow : force_fit_type (t, overflow))
+ = ((notrunc ? !uns && overflow : force_fit_type (t, overflow && !uns))
| TREE_OVERFLOW (arg1)
| TREE_OVERFLOW (arg2));
TREE_CONSTANT_OVERFLOW (t) = (TREE_OVERFLOW (t)
{
REAL_VALUE_TYPE d1;
REAL_VALUE_TYPE d2;
+ int overflow = 0;
REAL_VALUE_TYPE value;
tree t;
d1 = TREE_REAL_CST (arg1);
d2 = TREE_REAL_CST (arg2);
- if (setjmp (float_error))
+
+ /* If either operand is a NaN, just return it. Otherwise, set up
+ for floating-point trap; we return an overflow. */
+ if (REAL_VALUE_ISNAN (d1))
+ return arg1;
+ else if (REAL_VALUE_ISNAN (d2))
+ return arg2;
+ else if (setjmp (float_error))
{
- pedwarn ("floating overflow in constant expression");
- return build (code, TREE_TYPE (arg1), arg1, arg2);
+ t = copy_node (arg1);
+ overflow = 1;
+ goto got_float;
}
+
set_float_handler (float_error);
#ifdef REAL_ARITHMETIC
#endif /* no REAL_ARITHMETIC */
t = build_real (TREE_TYPE (arg1),
real_value_truncate (TYPE_MODE (TREE_TYPE (arg1)), value));
+ got_float:
set_float_handler (NULL_PTR);
+
+ TREE_OVERFLOW (t)
+ = (force_fit_type (t, overflow)
+ | TREE_OVERFLOW (arg1) | TREE_OVERFLOW (arg2));
+ TREE_CONSTANT_OVERFLOW (t)
+ = TREE_OVERFLOW (t)
+ | TREE_CONSTANT_OVERFLOW (arg1)
+ | TREE_CONSTANT_OVERFLOW (arg2);
return t;
}
#endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */
const_binop (MULT_EXPR, r2, r2, notrunc),
const_binop (MULT_EXPR, i2, i2, notrunc),
notrunc);
- t = build_complex (const_binop (RDIV_EXPR,
- const_binop (PLUS_EXPR,
- const_binop (MULT_EXPR, r1, r2, notrunc),
- const_binop (MULT_EXPR, i1, i2, notrunc),
- notrunc),
- magsquared, notrunc),
- const_binop (RDIV_EXPR,
- const_binop (MINUS_EXPR,
- const_binop (MULT_EXPR, i1, r2, notrunc),
- const_binop (MULT_EXPR, r1, i2, notrunc),
- notrunc),
- magsquared, notrunc));
+
+ t = build_complex
+ (const_binop (INTEGRAL_TYPE_P (TREE_TYPE (r1))
+ ? TRUNC_DIV_EXPR : RDIV_EXPR,
+ const_binop (PLUS_EXPR,
+ const_binop (MULT_EXPR, r1, r2,
+ notrunc),
+ const_binop (MULT_EXPR, i1, i2,
+ notrunc),
+ notrunc),
+ magsquared, notrunc),
+ const_binop (INTEGRAL_TYPE_P (TREE_TYPE (r1))
+ ? TRUNC_DIV_EXPR : RDIV_EXPR,
+ const_binop (MINUS_EXPR,
+ const_binop (MULT_EXPR, i1, r2,
+ notrunc),
+ const_binop (MULT_EXPR, r1, i2,
+ notrunc),
+ notrunc),
+ magsquared, notrunc));
}
break;
tree
size_int (number)
- unsigned int number;
+ unsigned HOST_WIDE_INT number;
{
register tree t;
/* Type-size nodes already made for small sizes. */
&& TREE_INT_CST_HIGH (arg0) == 0)
return arg1;
/* Handle general case of two integer constants. */
- return const_binop (code, arg0, arg1, 1);
+ return const_binop (code, arg0, arg1, 0);
}
if (arg0 == error_mark_node || arg1 == error_mark_node)
register tree arg1;
{
register tree type = TREE_TYPE (t);
+ int overflow = 0;
if (TREE_CODE (type) == POINTER_TYPE || INTEGRAL_TYPE_P (type))
{
if (TREE_CODE (arg1) == INTEGER_CST)
{
+ /* If we would build a constant wider than GCC supports,
+ leave the conversion unfolded. */
+ if (TYPE_PRECISION (type) > 2 * HOST_BITS_PER_WIDE_INT)
+ return t;
+
/* Given an integer constant, make new constant with new type,
appropriately sign-extended or truncated. */
t = build_int_2 (TREE_INT_CST_LOW (arg1),
#if !defined (REAL_IS_NOT_DOUBLE) || defined (REAL_ARITHMETIC)
else if (TREE_CODE (arg1) == REAL_CST)
{
- REAL_VALUE_TYPE l, x, u;
+ /* Don't initialize these, use assignments.
+ Initialized local aggregates don't work on old compilers. */
+ REAL_VALUE_TYPE x;
+ REAL_VALUE_TYPE l;
+ REAL_VALUE_TYPE u;
+ tree type1 = TREE_TYPE (arg1);
- l = real_value_from_int_cst (TYPE_MIN_VALUE (type));
x = TREE_REAL_CST (arg1);
- u = real_value_from_int_cst (TYPE_MAX_VALUE (type));
-
+ l = real_value_from_int_cst (type1, TYPE_MIN_VALUE (type));
+ u = real_value_from_int_cst (type1, TYPE_MAX_VALUE (type));
/* See if X will be in range after truncation towards 0.
To compensate for truncation, move the bounds away from 0,
but reject if X exactly equals the adjusted bounds. */
l--;
u++;
#endif
- if (! (REAL_VALUES_LESS (l, x) && REAL_VALUES_LESS (x, u)))
- {
- pedwarn ("real constant out of range for integer conversion");
- return t;
- }
+ /* If X is a NaN, use zero instead and show we have an overflow.
+ Otherwise, range check. */
+ if (REAL_VALUE_ISNAN (x))
+ overflow = 1, x = dconst0;
+ else if (! (REAL_VALUES_LESS (l, x) && REAL_VALUES_LESS (x, u)))
+ overflow = 1;
+
#ifndef REAL_ARITHMETIC
{
- REAL_VALUE_TYPE d;
HOST_WIDE_INT low, high;
HOST_WIDE_INT half_word
= (HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2);
- d = TREE_REAL_CST (arg1);
- if (d < 0)
- d = -d;
+ if (x < 0)
+ x = -x;
- high = (HOST_WIDE_INT) (d / half_word / half_word);
- d -= (REAL_VALUE_TYPE) high * half_word * half_word;
- if (d >= (REAL_VALUE_TYPE) half_word * half_word / 2)
+ high = (HOST_WIDE_INT) (x / half_word / half_word);
+ x -= (REAL_VALUE_TYPE) high * half_word * half_word;
+ if (x >= (REAL_VALUE_TYPE) half_word * half_word / 2)
{
- low = d - (REAL_VALUE_TYPE) half_word * half_word / 2;
+ low = x - (REAL_VALUE_TYPE) half_word * half_word / 2;
low |= (HOST_WIDE_INT) -1 << (HOST_BITS_PER_WIDE_INT - 1);
}
else
- low = (HOST_WIDE_INT) d;
+ low = (HOST_WIDE_INT) x;
if (TREE_REAL_CST (arg1) < 0)
neg_double (low, high, &low, &high);
t = build_int_2 (low, high);
#else
{
HOST_WIDE_INT low, high;
- REAL_VALUE_TO_INT (&low, &high, (TREE_REAL_CST (arg1)));
+ REAL_VALUE_TO_INT (&low, &high, x);
t = build_int_2 (low, high);
}
#endif
TREE_TYPE (t) = type;
- force_fit_type (t, 0);
+ TREE_OVERFLOW (t)
+ = TREE_OVERFLOW (arg1) | force_fit_type (t, overflow);
+ TREE_CONSTANT_OVERFLOW (t)
+ = TREE_OVERFLOW (t) | TREE_CONSTANT_OVERFLOW (arg1);
}
#endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */
TREE_TYPE (t) = type;
#endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */
if (TREE_CODE (arg1) == REAL_CST)
{
- if (setjmp (float_error))
+ if (REAL_VALUE_ISNAN (TREE_REAL_CST (arg1)))
{
- pedwarn ("floating overflow in constant expression");
+ t = arg1;
+ TREE_TYPE (arg1) = type;
return t;
}
+ else if (setjmp (float_error))
+ {
+ overflow = 1;
+ t = copy_node (arg1);
+ goto got_it;
+ }
set_float_handler (float_error);
t = build_real (type, real_value_truncate (TYPE_MODE (type),
TREE_REAL_CST (arg1)));
set_float_handler (NULL_PTR);
+
+ got_it:
+ TREE_OVERFLOW (t)
+ = TREE_OVERFLOW (arg1) | force_fit_type (t, overflow);
+ TREE_CONSTANT_OVERFLOW (t)
+ = TREE_OVERFLOW (t) | TREE_CONSTANT_OVERFLOW (arg1);
return t;
}
}
return result;
}
+/* Nonzero means lvalues are limited to those valid in pedantic ANSI C.
+ Zero means allow extended lvalues. */
+
+int pedantic_lvalues;
+
/* When pedantic, return an expr equal to X but certainly not valid as a
pedantic lvalue. Otherwise, return X. */
pedantic_non_lvalue (x)
tree x;
{
- if (pedantic)
+ if (pedantic_lvalues)
return non_lvalue (x);
else
return x;
abort ();
}
}
+
+/* Return nonzero if CODE is a tree code that represents a truth value. */
+
+static int
+truth_value_p (code)
+ enum tree_code code;
+{
+ return (TREE_CODE_CLASS (code) == '<'
+ || code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR
+ || code == TRUTH_OR_EXPR || code == TRUTH_ORIF_EXPR
+ || code == TRUTH_XOR_EXPR || code == TRUTH_NOT_EXPR);
+}
\f
/* Return nonzero if two operands are necessarily equal.
If ONLY_CONST is non-zero, only return non-zero for constants.
/* Detect when real constants are equal. */
if (TREE_CODE (arg0) == TREE_CODE (arg1)
&& TREE_CODE (arg0) == REAL_CST)
- return !bcmp (&TREE_REAL_CST (arg0), &TREE_REAL_CST (arg1),
+ return !bcmp ((char *) &TREE_REAL_CST (arg0),
+ (char *) &TREE_REAL_CST (arg1),
sizeof (REAL_VALUE_TYPE));
if (only_const)
{
int unsignedp1, unsignedpo;
tree primarg1, primother;
- int correct_width;
+ unsigned correct_width;
if (operand_equal_p (arg0, arg1, 0))
return 1;
- if (! INTEGRAL_TYPE_P (TREE_TYPE (arg0)))
+ if (! INTEGRAL_TYPE_P (TREE_TYPE (arg0))
+ || ! INTEGRAL_TYPE_P (TREE_TYPE (arg1)))
return 0;
/* Duplicate what shorten_compare does to ARG1 and see if that gives the
two different values, which will be stored in *CVAL1 and *CVAL2; if
they are non-zero it means that some operands have already been found.
No variables may be used anywhere else in the expression except in the
- comparisons.
+ comparisons. If SAVE_P is true it means we removed a SAVE_EXPR around
+ the expression and save_expr needs to be called with CVAL1 and CVAL2.
If this is true, return 1. Otherwise, return zero. */
static int
-twoval_comparison_p (arg, cval1, cval2)
+twoval_comparison_p (arg, cval1, cval2, save_p)
tree arg;
tree *cval1, *cval2;
+ int *save_p;
{
enum tree_code code = TREE_CODE (arg);
char class = TREE_CODE_CLASS (code);
/* We can handle some of the 'e' cases here. */
- if (class == 'e'
- && (code == TRUTH_NOT_EXPR
- || (code == SAVE_EXPR && SAVE_EXPR_RTL (arg) == 0)))
+ if (class == 'e' && code == TRUTH_NOT_EXPR)
class = '1';
else if (class == 'e'
&& (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR
|| code == COMPOUND_EXPR))
class = '2';
+ /* ??? Disable this since the SAVE_EXPR might already be in use outside
+ the expression. There may be no way to make this work, but it needs
+ to be looked at again for 2.6. */
+#if 0
+ else if (class == 'e' && code == SAVE_EXPR && SAVE_EXPR_RTL (arg) == 0)
+ {
+ /* If we've already found a CVAL1 or CVAL2, this expression is
+ two complex to handle. */
+ if (*cval1 || *cval2)
+ return 0;
+
+ class = '1';
+ *save_p = 1;
+ }
+#endif
+
switch (class)
{
case '1':
- return twoval_comparison_p (TREE_OPERAND (arg, 0), cval1, cval2);
+ return twoval_comparison_p (TREE_OPERAND (arg, 0), cval1, cval2, save_p);
case '2':
- return (twoval_comparison_p (TREE_OPERAND (arg, 0), cval1, cval2)
- && twoval_comparison_p (TREE_OPERAND (arg, 1), cval1, cval2));
+ return (twoval_comparison_p (TREE_OPERAND (arg, 0), cval1, cval2, save_p)
+ && twoval_comparison_p (TREE_OPERAND (arg, 1),
+ cval1, cval2, save_p));
case 'c':
return 1;
case 'e':
if (code == COND_EXPR)
- return (twoval_comparison_p (TREE_OPERAND (arg, 0), cval1, cval2)
- && twoval_comparison_p (TREE_OPERAND (arg, 1), cval1, cval2)
+ return (twoval_comparison_p (TREE_OPERAND (arg, 0),
+ cval1, cval2, save_p)
+ && twoval_comparison_p (TREE_OPERAND (arg, 1),
+ cval1, cval2, save_p)
&& twoval_comparison_p (TREE_OPERAND (arg, 2),
- cval1, cval2));
+ cval1, cval2, save_p));
return 0;
case '<':
return non_lvalue (t);
}
+
+/* Similar, but call pedantic_non_lvalue instead of non_lvalue. */
+
+static tree
+pedantic_omit_one_operand (type, result, omitted)
+ tree type, result, omitted;
+{
+ tree t = convert (type, result);
+
+ if (TREE_SIDE_EFFECTS (omitted))
+ return build (COMPOUND_EXPR, type, omitted, t);
+
+ return pedantic_non_lvalue (t);
+}
+
+
\f
/* Return a simplified tree node for the truth-negation of ARG. This
never alters ARG itself. We assume that ARG is an operation that
invert_truthvalue (TREE_OPERAND (arg, 0)));
case BIT_AND_EXPR:
- if (! integer_onep (TREE_OPERAND (arg, 1)))
- abort ();
+ if (!integer_onep (TREE_OPERAND (arg, 1)))
+ break;
return build (EQ_EXPR, type, arg, convert (type, integer_zero_node));
- }
- abort ();
+ case SAVE_EXPR:
+ return build1 (TRUTH_NOT_EXPR, type, arg);
+
+ case CLEANUP_POINT_EXPR:
+ return build1 (CLEANUP_POINT_EXPR, type,
+ invert_truthvalue (TREE_OPERAND (arg, 0)));
+ }
+ if (TREE_CODE (TREE_TYPE (arg)) != BOOLEAN_TYPE)
+ abort ();
+ return build1 (TRUTH_NOT_EXPR, type, arg);
}
/* Given a bit-wise operation CODE applied to ARG0 and ARG1, see if both
extraction at all and so can do nothing. */
linner = get_inner_reference (lhs, &lbitsize, &lbitpos, &offset, &lmode,
&lunsignedp, &lvolatilep);
- if (lbitsize == GET_MODE_BITSIZE (lmode) || lbitsize < 0
+ if (linner == lhs || lbitsize == GET_MODE_BITSIZE (lmode) || lbitsize < 0
|| offset != 0)
return 0;
rinner = get_inner_reference (rhs, &rbitsize, &rbitpos, &offset,
&rmode, &runsignedp, &rvolatilep);
- if (lbitpos != rbitpos || lbitsize != rbitsize
+ if (rinner == rhs || lbitpos != rbitpos || lbitsize != rbitsize
|| lunsignedp != runsignedp || offset != 0)
return 0;
}
return 0;
}
-#if BYTES_BIG_ENDIAN
- lbitpos = lnbitsize - lbitsize - lbitpos;
-#endif
+ if (BYTES_BIG_ENDIAN)
+ lbitpos = lnbitsize - lbitsize - lbitpos;
/* Make the mask to be used against the extracted field. */
mask = build_int_2 (~0, ~0);
appropriate number of bits and mask it with the computed mask
(in case this was a signed field). If we changed it, make a new one. */
lhs = make_bit_field_ref (linner, unsigned_type, lnbitsize, lnbitpos, 1);
+ if (lvolatilep)
+ {
+ TREE_SIDE_EFFECTS (lhs) = 1;
+ TREE_THIS_VOLATILE (lhs) = 1;
+ }
rhs = fold (const_binop (BIT_AND_EXPR,
const_binop (LSHIFT_EXPR,
*PMASK is set to the mask used. This is either contained in a
BIT_AND_EXPR or derived from the width of the field.
+ *PAND_MASK is set the the mask found in a BIT_AND_EXPR, if any.
+
Return 0 if this is not a component reference or is one that we can't
do anything with. */
static tree
decode_field_reference (exp, pbitsize, pbitpos, pmode, punsignedp,
- pvolatilep, pmask)
+ pvolatilep, pmask, pand_mask)
tree exp;
int *pbitsize, *pbitpos;
enum machine_mode *pmode;
int *punsignedp, *pvolatilep;
tree *pmask;
+ tree *pand_mask;
{
- tree mask = 0;
- tree inner;
- tree offset;
+ tree and_mask = 0;
+ tree mask, inner, offset;
+ tree unsigned_type;
+ int precision;
/* All the optimizations using this function assume integer fields.
There are problems with FP fields since the type_for_size call
if (TREE_CODE (exp) == BIT_AND_EXPR)
{
- mask = TREE_OPERAND (exp, 1);
+ and_mask = TREE_OPERAND (exp, 1);
exp = TREE_OPERAND (exp, 0);
- STRIP_NOPS (exp); STRIP_NOPS (mask);
- if (TREE_CODE (mask) != INTEGER_CST)
+ STRIP_NOPS (exp); STRIP_NOPS (and_mask);
+ if (TREE_CODE (and_mask) != INTEGER_CST)
return 0;
}
- if (TREE_CODE (exp) != COMPONENT_REF && TREE_CODE (exp) != ARRAY_REF
- && TREE_CODE (exp) != BIT_FIELD_REF)
- return 0;
inner = get_inner_reference (exp, pbitsize, pbitpos, &offset, pmode,
punsignedp, pvolatilep);
- if (*pbitsize < 0 || offset != 0)
+ if ((inner == exp && and_mask == 0)
+ || *pbitsize < 0 || offset != 0)
return 0;
- if (mask == 0)
- {
- tree unsigned_type = type_for_size (*pbitsize, 1);
- int precision = TYPE_PRECISION (unsigned_type);
-
- mask = build_int_2 (~0, ~0);
- TREE_TYPE (mask) = unsigned_type;
- force_fit_type (mask, 0);
- mask = const_binop (LSHIFT_EXPR, mask, size_int (precision - *pbitsize), 0);
- mask = const_binop (RSHIFT_EXPR, mask, size_int (precision - *pbitsize), 0);
- }
+ /* Compute the mask to access the bitfield. */
+ unsigned_type = type_for_size (*pbitsize, 1);
+ precision = TYPE_PRECISION (unsigned_type);
+
+ mask = build_int_2 (~0, ~0);
+ TREE_TYPE (mask) = unsigned_type;
+ force_fit_type (mask, 0);
+ mask = const_binop (LSHIFT_EXPR, mask, size_int (precision - *pbitsize), 0);
+ mask = const_binop (RSHIFT_EXPR, mask, size_int (precision - *pbitsize), 0);
+
+ /* Merge it with the mask we found in the BIT_AND_EXPR, if any. */
+ if (and_mask != 0)
+ mask = fold (build (BIT_AND_EXPR, unsigned_type,
+ convert (unsigned_type, and_mask), mask));
*pmask = mask;
+ *pand_mask = and_mask;
return inner;
}
TREE_TYPE (tmask) = signed_type (type);
force_fit_type (tmask, 0);
return
- operand_equal_p (mask,
- const_binop (RSHIFT_EXPR,
- const_binop (LSHIFT_EXPR, tmask,
- size_int (precision - size), 0),
- size_int (precision - size), 0),
- 0);
+ tree_int_cst_equal (mask,
+ const_binop (RSHIFT_EXPR,
+ const_binop (LSHIFT_EXPR, tmask,
+ size_int (precision - size),
+ 0),
+ size_int (precision - size), 0));
}
/* Subroutine for fold_truthop: determine if an operand is simple enough
const_binop (MINUS_EXPR, hi_cst, lo_cst, 0))));
}
\f
+/* Subroutine for fold_truthop: C is an INTEGER_CST interpreted as a P
+ bit value. Arrange things so the extra bits will be set to zero if and
+ only if C is signed-extended to its full width. If MASK is nonzero,
+ it is an INTEGER_CST that should be AND'ed with the extra bits. */
+
+static tree
+unextend (c, p, unsignedp, mask)
+ tree c;
+ int p;
+ int unsignedp;
+ tree mask;
+{
+ tree type = TREE_TYPE (c);
+ int modesize = GET_MODE_BITSIZE (TYPE_MODE (type));
+ tree temp;
+
+ if (p == modesize || unsignedp)
+ return c;
+
+ if (TREE_UNSIGNED (type))
+ c = convert (signed_type (type), c);
+
+ /* We work by getting just the sign bit into the low-order bit, then
+ into the high-order bit, then sign-extend. We then XOR that value
+ with C. */
+ temp = const_binop (RSHIFT_EXPR, c, size_int (p - 1), 0);
+ temp = const_binop (BIT_AND_EXPR, temp, size_int (1), 0);
+ temp = const_binop (LSHIFT_EXPR, temp, size_int (modesize - 1), 0);
+ temp = const_binop (RSHIFT_EXPR, temp, size_int (modesize - p - 1), 0);
+ if (mask != 0)
+ temp = const_binop (BIT_AND_EXPR, temp, convert (TREE_TYPE (c), mask), 0);
+
+ return convert (type, const_binop (BIT_XOR_EXPR, c, temp, 0));
+}
+\f
/* Find ways of folding logical expressions of LHS and RHS:
Try to merge two comparisons to the same innermost item.
Look for range tests like "ch >= '0' && ch <= '9'".
enum machine_mode ll_mode, lr_mode, rl_mode, rr_mode;
enum machine_mode lnmode, rnmode;
tree ll_mask, lr_mask, rl_mask, rr_mask;
+ tree ll_and_mask, lr_and_mask, rl_and_mask, rr_and_mask;
tree l_const, r_const;
tree type, result;
int first_bit, end_bit;
volatilep = 0;
ll_inner = decode_field_reference (ll_arg,
&ll_bitsize, &ll_bitpos, &ll_mode,
- &ll_unsignedp, &volatilep, &ll_mask);
+ &ll_unsignedp, &volatilep, &ll_mask,
+ &ll_and_mask);
lr_inner = decode_field_reference (lr_arg,
&lr_bitsize, &lr_bitpos, &lr_mode,
- &lr_unsignedp, &volatilep, &lr_mask);
+ &lr_unsignedp, &volatilep, &lr_mask,
+ &lr_and_mask);
rl_inner = decode_field_reference (rl_arg,
&rl_bitsize, &rl_bitpos, &rl_mode,
- &rl_unsignedp, &volatilep, &rl_mask);
+ &rl_unsignedp, &volatilep, &rl_mask,
+ &rl_and_mask);
rr_inner = decode_field_reference (rr_arg,
&rr_bitsize, &rr_bitpos, &rr_mode,
- &rr_unsignedp, &volatilep, &rr_mask);
+ &rr_unsignedp, &volatilep, &rr_mask,
+ &rr_and_mask);
/* It must be true that the inner operation on the lhs of each
comparison must be the same if we are to be able to do anything.
type = type_for_size (lnbitsize, 1);
xll_bitpos = ll_bitpos - lnbitpos, xrl_bitpos = rl_bitpos - lnbitpos;
-#if BYTES_BIG_ENDIAN
- xll_bitpos = lnbitsize - xll_bitpos - ll_bitsize;
- xrl_bitpos = lnbitsize - xrl_bitpos - rl_bitsize;
-#endif
+ if (BYTES_BIG_ENDIAN)
+ {
+ xll_bitpos = lnbitsize - xll_bitpos - ll_bitsize;
+ xrl_bitpos = lnbitsize - xrl_bitpos - rl_bitsize;
+ }
ll_mask = const_binop (LSHIFT_EXPR, convert (type, ll_mask),
size_int (xll_bitpos), 0);
rl_mask = const_binop (LSHIFT_EXPR, convert (type, rl_mask),
size_int (xrl_bitpos), 0);
- /* Make sure the constants are interpreted as unsigned, so we
- don't have sign bits outside the range of their type. */
-
if (l_const)
{
- l_const = convert (unsigned_type (TREE_TYPE (l_const)), l_const);
- l_const = const_binop (LSHIFT_EXPR, convert (type, l_const),
- size_int (xll_bitpos), 0);
+ l_const = convert (type, l_const);
+ l_const = unextend (l_const, ll_bitsize, ll_unsignedp, ll_and_mask);
+ l_const = const_binop (LSHIFT_EXPR, l_const, size_int (xll_bitpos), 0);
+ if (! integer_zerop (const_binop (BIT_AND_EXPR, l_const,
+ fold (build1 (BIT_NOT_EXPR,
+ type, ll_mask)),
+ 0)))
+ {
+ warning ("comparison is always %s",
+ wanted_code == NE_EXPR ? "one" : "zero");
+
+ return convert (truth_type,
+ wanted_code == NE_EXPR
+ ? integer_one_node : integer_zero_node);
+ }
}
if (r_const)
{
- r_const = convert (unsigned_type (TREE_TYPE (r_const)), r_const);
- r_const = const_binop (LSHIFT_EXPR, convert (type, r_const),
- size_int (xrl_bitpos), 0);
+ r_const = convert (type, r_const);
+ r_const = unextend (r_const, rl_bitsize, rl_unsignedp, rl_and_mask);
+ r_const = const_binop (LSHIFT_EXPR, r_const, size_int (xrl_bitpos), 0);
+ if (! integer_zerop (const_binop (BIT_AND_EXPR, r_const,
+ fold (build1 (BIT_NOT_EXPR,
+ type, rl_mask)),
+ 0)))
+ {
+ warning ("comparison is always %s",
+ wanted_code == NE_EXPR ? "one" : "zero");
+
+ return convert (truth_type,
+ wanted_code == NE_EXPR
+ ? integer_one_node : integer_zero_node);
+ }
}
/* If the right sides are not constant, do the same for it. Also,
rnbitpos = first_bit & ~ (rnbitsize - 1);
xlr_bitpos = lr_bitpos - rnbitpos, xrr_bitpos = rr_bitpos - rnbitpos;
-#if BYTES_BIG_ENDIAN
- xlr_bitpos = rnbitsize - xlr_bitpos - lr_bitsize;
- xrr_bitpos = rnbitsize - xrr_bitpos - rr_bitsize;
-#endif
+ if (BYTES_BIG_ENDIAN)
+ {
+ xlr_bitpos = rnbitsize - xlr_bitpos - lr_bitsize;
+ xrr_bitpos = rnbitsize - xrr_bitpos - rr_bitsize;
+ }
lr_mask = const_binop (LSHIFT_EXPR, convert (type, lr_mask),
size_int (xlr_bitpos), 0);
const_binop (BIT_IOR_EXPR, l_const, r_const, 0));
}
\f
+/* If T contains a COMPOUND_EXPR which was inserted merely to evaluate
+ S, a SAVE_EXPR, return the expression actually being evaluated. Note
+ that we may sometimes modify the tree. */
+
+static tree
+strip_compound_expr (t, s)
+ tree t;
+ tree s;
+{
+ tree type = TREE_TYPE (t);
+ enum tree_code code = TREE_CODE (t);
+
+ /* See if this is the COMPOUND_EXPR we want to eliminate. */
+ if (code == COMPOUND_EXPR && TREE_CODE (TREE_OPERAND (t, 0)) == CONVERT_EXPR
+ && TREE_OPERAND (TREE_OPERAND (t, 0), 0) == s)
+ return TREE_OPERAND (t, 1);
+
+ /* See if this is a COND_EXPR or a simple arithmetic operator. We
+ don't bother handling any other types. */
+ else if (code == COND_EXPR)
+ {
+ TREE_OPERAND (t, 0) = strip_compound_expr (TREE_OPERAND (t, 0), s);
+ TREE_OPERAND (t, 1) = strip_compound_expr (TREE_OPERAND (t, 1), s);
+ TREE_OPERAND (t, 2) = strip_compound_expr (TREE_OPERAND (t, 2), s);
+ }
+ else if (TREE_CODE_CLASS (code) == '1')
+ TREE_OPERAND (t, 0) = strip_compound_expr (TREE_OPERAND (t, 0), s);
+ else if (TREE_CODE_CLASS (code) == '<'
+ || TREE_CODE_CLASS (code) == '2')
+ {
+ TREE_OPERAND (t, 0) = strip_compound_expr (TREE_OPERAND (t, 0), s);
+ TREE_OPERAND (t, 1) = strip_compound_expr (TREE_OPERAND (t, 1), s);
+ }
+
+ return t;
+}
+\f
/* Perform constant folding and related simplification of EXPR.
The related simplifications include x*1 => x, x*0 => 0, etc.,
and application of the associative law.
int wins = 1;
+ /* Don't try to process an RTL_EXPR since its operands aren't trees. */
+ if (code == RTL_EXPR)
+ return t;
+
/* Return right away if already constant. */
if (TREE_CONSTANT (t))
{
expand_expr.
Before we do that, see if this is a BIT_AND_EXPR or a BIT_OR_EXPR,
- one of the operands is a comparison and the other is either a comparison
- or a BIT_AND_EXPR with the constant 1. In that case, the code below
- would make the expression more complex. Change it to a
- TRUTH_{AND,OR}_EXPR. */
-
- if ((code == BIT_AND_EXPR || code == BIT_IOR_EXPR)
- && ((TREE_CODE_CLASS (TREE_CODE (arg0)) == '<'
- && (TREE_CODE_CLASS (TREE_CODE (arg1)) == '<'
+ one of the operands is a comparison and the other is a comparison, a
+ BIT_AND_EXPR with the constant 1, or a truth value. In that case, the
+ code below would make the expression more complex. Change it to a
+ TRUTH_{AND,OR}_EXPR. Likewise, convert a similar NE_EXPR to
+ TRUTH_XOR_EXPR and an EQ_EXPR to the inversion of a TRUTH_XOR_EXPR. */
+
+ if ((code == BIT_AND_EXPR || code == BIT_IOR_EXPR
+ || code == EQ_EXPR || code == NE_EXPR)
+ && ((truth_value_p (TREE_CODE (arg0))
+ && (truth_value_p (TREE_CODE (arg1))
|| (TREE_CODE (arg1) == BIT_AND_EXPR
&& integer_onep (TREE_OPERAND (arg1, 1)))))
- || (TREE_CODE_CLASS (TREE_CODE (arg1)) == '<'
- && (TREE_CODE_CLASS (TREE_CODE (arg0)) == '<'
+ || (truth_value_p (TREE_CODE (arg1))
+ && (truth_value_p (TREE_CODE (arg0))
|| (TREE_CODE (arg0) == BIT_AND_EXPR
&& integer_onep (TREE_OPERAND (arg0, 1)))))))
- return fold (build (code == BIT_AND_EXPR ? TRUTH_AND_EXPR : TRUTH_OR_EXPR,
- type, arg0, arg1));
+ {
+ t = fold (build (code == BIT_AND_EXPR ? TRUTH_AND_EXPR
+ : code == BIT_IOR_EXPR ? TRUTH_OR_EXPR
+ : TRUTH_XOR_EXPR,
+ type, arg0, arg1));
+
+ if (code == EQ_EXPR)
+ t = invert_truthvalue (t);
+
+ return t;
+ }
if (TREE_CODE_CLASS (code) == '1')
{
fold (build1 (code, type, TREE_OPERAND (arg0, 2)))));
/* If this was a conversion, and all we did was to move into
- inside the COND_EXPR, bring it back out. Then return so we
- don't get into an infinite recursion loop taking the conversion
- out and then back in. */
+ inside the COND_EXPR, bring it back out. But leave it if
+ it is a conversion from integer to integer and the
+ result precision is no wider than a word since such a
+ conversion is cheap and may be optimized away by combine,
+ while it couldn't if it were outside the COND_EXPR. Then return
+ so we don't get into an infinite recursion loop taking the
+ conversion out and then back in. */
if ((code == NOP_EXPR || code == CONVERT_EXPR
|| code == NON_LVALUE_EXPR)
&& TREE_CODE (TREE_OPERAND (t, 1)) == code
&& TREE_CODE (TREE_OPERAND (t, 2)) == code
&& (TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 1), 0))
- == TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 2), 0))))
+ == TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 2), 0)))
+ && ! (INTEGRAL_TYPE_P (TREE_TYPE (t))
+ && INTEGRAL_TYPE_P (TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 1), 0)))
+ && TYPE_PRECISION (TREE_TYPE (t)) <= BITS_PER_WORD))
t = build1 (code, type,
build (COND_EXPR,
TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 1), 0)),
}
else
{
+ tree testtype = TREE_TYPE (arg1);
test = arg1;
- true_value = integer_one_node;
- false_value = integer_zero_node;
+ true_value = convert (testtype, integer_one_node);
+ false_value = convert (testtype, integer_zero_node);
}
/* If ARG0 is complex we want to make sure we only evaluate
succeed in folding one part to a constant, we do not need
to make this SAVE_EXPR. Since we do this optimization
primarily to see if we do end up with constant and this
- SAVE_EXPR interfers with later optimizations, suppressing
+ SAVE_EXPR interferes with later optimizations, suppressing
it when we can is important. */
- if ((TREE_CODE (arg0) != VAR_DECL && TREE_CODE (arg0) != PARM_DECL)
- || TREE_SIDE_EFFECTS (arg0))
+ if (TREE_CODE (arg0) != SAVE_EXPR
+ && ((TREE_CODE (arg0) != VAR_DECL
+ && TREE_CODE (arg0) != PARM_DECL)
+ || TREE_SIDE_EFFECTS (arg0)))
{
tree lhs = fold (build (code, type, arg0, true_value));
tree rhs = fold (build (code, type, arg0, false_value));
fold (build (code, type, arg0, false_value))));
if (TREE_CODE (arg0) == SAVE_EXPR)
return build (COMPOUND_EXPR, type,
- convert (void_type_node, arg0), test);
+ convert (void_type_node, arg0),
+ strip_compound_expr (test, arg0));
else
return convert (type, test);
}
}
else
{
+ tree testtype = TREE_TYPE (arg0);
test = arg0;
- true_value = integer_one_node;
- false_value = integer_zero_node;
+ true_value = convert (testtype, integer_one_node);
+ false_value = convert (testtype, integer_zero_node);
}
- if ((TREE_CODE (arg1) != VAR_DECL && TREE_CODE (arg1) != PARM_DECL)
- || TREE_SIDE_EFFECTS (arg1))
+ if (TREE_CODE (arg1) != SAVE_EXPR
+ && ((TREE_CODE (arg1) != VAR_DECL
+ && TREE_CODE (arg1) != PARM_DECL)
+ || TREE_SIDE_EFFECTS (arg1)))
{
tree lhs = fold (build (code, type, true_value, arg1));
tree rhs = fold (build (code, type, false_value, arg1));
- if (TREE_CONSTANT (lhs) || TREE_CONSTANT (rhs))
+ if (TREE_CONSTANT (lhs) || TREE_CONSTANT (rhs)
+ || TREE_CONSTANT (arg1))
return fold (build (COND_EXPR, type, test, lhs, rhs));
arg1 = save_expr (arg1);
fold (build (code, type, false_value, arg1))));
if (TREE_CODE (arg1) == SAVE_EXPR)
return build (COMPOUND_EXPR, type,
- convert (void_type_node, arg1), test);
+ convert (void_type_node, arg1),
+ strip_compound_expr (test, arg1));
else
return convert (type, test);
}
case CONVERT_EXPR:
case FIX_TRUNC_EXPR:
/* Other kinds of FIX are not handled properly by fold_convert. */
- /* Two conversions in a row are not needed unless:
- - the intermediate type is narrower than both initial and final, or
- - the intermediate type and innermost type differ in signedness,
- and the outermost type is wider than the intermediate, or
- - the initial type is a pointer type and the precisions of the
- intermediate and final types differ, or
- - the final type is a pointer type and the precisions of the
- initial and intermediate types differ. */
- if ((TREE_CODE (TREE_OPERAND (t, 0)) == NOP_EXPR
- || TREE_CODE (TREE_OPERAND (t, 0)) == CONVERT_EXPR)
- && (TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (t, 0)))
- > TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 0), 0)))
- ||
- TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (t, 0)))
- > TYPE_PRECISION (TREE_TYPE (t)))
- && ! ((TREE_CODE (TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 0), 0)))
- == INTEGER_TYPE)
- && (TREE_CODE (TREE_TYPE (TREE_OPERAND (t, 0)))
- == INTEGER_TYPE)
- && (TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (t, 0)))
- != TREE_UNSIGNED (TREE_OPERAND (TREE_OPERAND (t, 0), 0)))
- && (TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (t, 0)))
- < TYPE_PRECISION (TREE_TYPE (t))))
- && ((TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (t, 0)))
- && (TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (t, 0)))
- > TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 0), 0)))))
- ==
- (TREE_UNSIGNED (TREE_TYPE (t))
- && (TYPE_PRECISION (TREE_TYPE (t))
- > TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (t, 0))))))
- && ! ((TREE_CODE (TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 0), 0)))
- == POINTER_TYPE)
- && (TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (t, 0)))
- != TYPE_PRECISION (TREE_TYPE (t))))
- && ! (TREE_CODE (TREE_TYPE (t)) == POINTER_TYPE
- && (TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 0), 0)))
- != TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (t, 0))))))
- return convert (TREE_TYPE (t), TREE_OPERAND (TREE_OPERAND (t, 0), 0));
+
+ if (TREE_TYPE (TREE_OPERAND (t, 0)) == TREE_TYPE (t))
+ return TREE_OPERAND (t, 0);
+
+ /* Handle cases of two conversions in a row. */
+ if (TREE_CODE (TREE_OPERAND (t, 0)) == NOP_EXPR
+ || TREE_CODE (TREE_OPERAND (t, 0)) == CONVERT_EXPR)
+ {
+ tree inside_type = TREE_TYPE (TREE_OPERAND (TREE_OPERAND (t, 0), 0));
+ tree inter_type = TREE_TYPE (TREE_OPERAND (t, 0));
+ tree final_type = TREE_TYPE (t);
+ int inside_int = INTEGRAL_TYPE_P (inside_type);
+ int inside_ptr = POINTER_TYPE_P (inside_type);
+ int inside_float = FLOAT_TYPE_P (inside_type);
+ int inside_prec = TYPE_PRECISION (inside_type);
+ int inside_unsignedp = TREE_UNSIGNED (inside_type);
+ int inter_int = INTEGRAL_TYPE_P (inter_type);
+ int inter_ptr = POINTER_TYPE_P (inter_type);
+ int inter_float = FLOAT_TYPE_P (inter_type);
+ int inter_prec = TYPE_PRECISION (inter_type);
+ int inter_unsignedp = TREE_UNSIGNED (inter_type);
+ int final_int = INTEGRAL_TYPE_P (final_type);
+ int final_ptr = POINTER_TYPE_P (final_type);
+ int final_float = FLOAT_TYPE_P (final_type);
+ int final_prec = TYPE_PRECISION (final_type);
+ int final_unsignedp = TREE_UNSIGNED (final_type);
+
+ /* In addition to the cases of two conversions in a row
+ handled below, if we are converting something to its own
+ type via an object of identical or wider precision, neither
+ conversion is needed. */
+ if (inside_type == final_type
+ && ((inter_int && final_int) || (inter_float && final_float))
+ && inter_prec >= final_prec)
+ return TREE_OPERAND (TREE_OPERAND (t, 0), 0);
+
+ /* Likewise, if the intermediate and final types are either both
+ float or both integer, we don't need the middle conversion if
+ it is wider than the final type and doesn't change the signedness
+ (for integers). Avoid this if the final type is a pointer
+ since then we sometimes need the inner conversion. Likewise if
+ the outer has a precision not equal to the size of its mode. */
+ if ((((inter_int || inter_ptr) && (inside_int || inside_ptr))
+ || (inter_float && inside_float))
+ && inter_prec >= inside_prec
+ && (inter_float || inter_unsignedp == inside_unsignedp)
+ && ! (final_prec != GET_MODE_BITSIZE (TYPE_MODE (final_type))
+ && TYPE_MODE (final_type) == TYPE_MODE (inter_type))
+ && ! final_ptr)
+ return convert (final_type, TREE_OPERAND (TREE_OPERAND (t, 0), 0));
+
+ /* Two conversions in a row are not needed unless:
+ - some conversion is floating-point (overstrict for now), or
+ - the intermediate type is narrower than both initial and
+ final, or
+ - the intermediate type and innermost type differ in signedness,
+ and the outermost type is wider than the intermediate, or
+ - the initial type is a pointer type and the precisions of the
+ intermediate and final types differ, or
+ - the final type is a pointer type and the precisions of the
+ initial and intermediate types differ. */
+ if (! inside_float && ! inter_float && ! final_float
+ && (inter_prec > inside_prec || inter_prec > final_prec)
+ && ! (inside_int && inter_int
+ && inter_unsignedp != inside_unsignedp
+ && inter_prec < final_prec)
+ && ((inter_unsignedp && inter_prec > inside_prec)
+ == (final_unsignedp && final_prec > inter_prec))
+ && ! (inside_ptr && inter_prec != final_prec)
+ && ! (final_ptr && inside_prec != inter_prec)
+ && ! (final_prec != GET_MODE_BITSIZE (TYPE_MODE (final_type))
+ && TYPE_MODE (final_type) == TYPE_MODE (inter_type))
+ && ! final_ptr)
+ return convert (final_type, TREE_OPERAND (TREE_OPERAND (t, 0), 0));
+ }
if (TREE_CODE (TREE_OPERAND (t, 0)) == MODIFY_EXPR
&& TREE_CONSTANT (TREE_OPERAND (TREE_OPERAND (t, 0), 1))
return t;
#endif /* 0 */
+ case COMPONENT_REF:
+ if (TREE_CODE (arg0) == CONSTRUCTOR)
+ {
+ tree m = purpose_member (arg1, CONSTRUCTOR_ELTS (arg0));
+ if (m)
+ t = TREE_VALUE (m);
+ }
+ return t;
+
case RANGE_EXPR:
TREE_CONSTANT (t) = wins;
return t;
TREE_TYPE (t) = type;
TREE_OVERFLOW (t)
= (TREE_OVERFLOW (arg0)
- | force_fit_type (t, overflow));
+ | force_fit_type (t, overflow && !TREE_UNSIGNED (type)));
TREE_CONSTANT_OVERFLOW (t)
= TREE_OVERFLOW (t) | TREE_CONSTANT_OVERFLOW (arg0);
}
TREE_OPERAND (arg0, 1)));
}
/* In IEEE floating point, x+0 may not equal x. */
- else if (TARGET_FLOAT_FORMAT != IEEE_FLOAT_FORMAT
+ else if ((TARGET_FLOAT_FORMAT != IEEE_FLOAT_FORMAT
+ || flag_fast_math)
&& real_zerop (arg1))
return non_lvalue (convert (type, arg0));
associate:
/* In most languages, can't associate operations on floats
through parentheses. Rather than remember where the parentheses
- were, we don't associate floats at all. It shouldn't matter much. */
- if (FLOAT_TYPE_P (type))
+ were, we don't associate floats at all. It shouldn't matter much.
+ However, associating multiplications is only very slightly
+ inaccurate, so do that if -ffast-math is specified. */
+ if (FLOAT_TYPE_P (type)
+ && ! (flag_fast_math && code == MULT_EXPR))
goto binary;
+
/* The varsign == -1 cases happen only for addition and subtraction.
It says that the arg that was split was really CON minus VAR.
The rest of the code applies to all associative operations. */
return t;
/* Otherwise return (CON +- ARG1) - VAR. */
- TREE_SET_CODE (t, MINUS_EXPR);
- TREE_OPERAND (t, 1) = var;
- TREE_OPERAND (t, 0)
- = fold (build (code, TREE_TYPE (t), con, arg1));
+ t = build (MINUS_EXPR, type,
+ fold (build (code, type, con, arg1)), var);
}
else
{
return t;
/* Otherwise return VAR +- (ARG1 +- CON). */
- TREE_OPERAND (t, 1) = tem
- = fold (build (code, TREE_TYPE (t), arg1, con));
- TREE_OPERAND (t, 0) = var;
+ tem = fold (build (code, type, arg1, con));
+ t = build (code, type, var, tem);
+
if (integer_zerop (tem)
&& (code == PLUS_EXPR || code == MINUS_EXPR))
return convert (type, var);
if (split_tree (arg1, code, &var, &con, &varsign))
{
+ if (TREE_CONSTANT (arg1))
+ return t;
+
+ if (varsign == -1)
+ TREE_SET_CODE (t,
+ (code == PLUS_EXPR ? MINUS_EXPR : PLUS_EXPR));
+
/* EXPR is ARG0 +- (CON +- VAR). */
if (TREE_CODE (t) == MINUS_EXPR
&& operand_equal_p (var, arg0, 0))
return fold (build1 (NEGATE_EXPR, TREE_TYPE (t),
convert (TREE_TYPE (t), con)));
}
- if (TREE_CONSTANT (arg1))
- return t;
- if (varsign == -1)
- TREE_SET_CODE (t,
- (code == PLUS_EXPR ? MINUS_EXPR : PLUS_EXPR));
- TREE_OPERAND (t, 0)
- = fold (build (code, TREE_TYPE (t), arg0, con));
- TREE_OPERAND (t, 1) = var;
+
+ t = build (TREE_CODE (t), type,
+ fold (build (code, TREE_TYPE (t), arg0, con)), var);
+
if (integer_zerop (TREE_OPERAND (t, 0))
&& TREE_CODE (t) == PLUS_EXPR)
return convert (TREE_TYPE (t), var);
/* Convert A - (-B) to A + B. */
else if (TREE_CODE (arg1) == NEGATE_EXPR)
return fold (build (PLUS_EXPR, type, arg0, TREE_OPERAND (arg1, 0)));
- else if (TARGET_FLOAT_FORMAT != IEEE_FLOAT_FORMAT)
+
+ else if (TARGET_FLOAT_FORMAT != IEEE_FLOAT_FORMAT
+ || flag_fast_math)
{
/* Except with IEEE floating point, 0-x equals -x. */
if (! wins && real_zerop (arg0))
/* Except with IEEE floating point, x-0 equals x. */
if (real_zerop (arg1))
return non_lvalue (convert (type, arg0));
+ }
- /* Fold &x - &x. This can happen from &x.foo - &x.
- This is unsafe for certain floats even in non-IEEE formats.
- In IEEE, it is unsafe because it does wrong for NaNs.
- Also note that operand_equal_p is always false if an operand
- is volatile. */
+ /* Fold &x - &x. This can happen from &x.foo - &x.
+ This is unsafe for certain floats even in non-IEEE formats.
+ In IEEE, it is unsafe because it does wrong for NaNs.
+ Also note that operand_equal_p is always false if an operand
+ is volatile. */
+
+ if ((! FLOAT_TYPE_P (type) || flag_fast_math)
+ && operand_equal_p (arg0, arg1, 0))
+ return convert (type, integer_zero_node);
- if (operand_equal_p (arg0, arg1, FLOAT_TYPE_P (type)))
- return convert (type, integer_zero_node);
- }
goto associate;
case MULT_EXPR:
if (integer_onep (arg1))
return non_lvalue (convert (type, arg0));
+ /* ((A / C) * C) is A if the division is an
+ EXACT_DIV_EXPR. Since C is normally a constant,
+ just check for one of the four possibilities. */
+
+ if (TREE_CODE (arg0) == EXACT_DIV_EXPR
+ && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
+ return TREE_OPERAND (arg0, 0);
+
/* (a * (1 << b)) is (a << b) */
if (TREE_CODE (arg1) == LSHIFT_EXPR
&& integer_onep (TREE_OPERAND (arg1, 0)))
else
{
/* x*0 is 0, except for IEEE floating point. */
- if (TARGET_FLOAT_FORMAT != IEEE_FLOAT_FORMAT
+ if ((TARGET_FLOAT_FORMAT != IEEE_FLOAT_FORMAT
+ || flag_fast_math)
&& real_zerop (arg1))
return omit_one_operand (type, arg1, arg0);
/* In IEEE floating point, x*1 is not equivalent to x for snans.
case BIT_IOR_EXPR:
bit_ior:
+ {
+ register enum tree_code code0, code1;
+
if (integer_all_onesp (arg1))
return omit_one_operand (type, arg1, arg0);
if (integer_zerop (arg1))
if (t1 != NULL_TREE)
return t1;
- /* (a << C1) | (a >> C2) if A is unsigned and C1+C2 is the size of A
+ /* (A << C1) | (A >> C2) if A is unsigned and C1+C2 is the size of A
is a rotate of A by C1 bits. */
+ /* (A << B) | (A >> (Z - B)) if A is unsigned and Z is the size of A
+ is a rotate of A by B bits. */
- if ((TREE_CODE (arg0) == RSHIFT_EXPR
- || TREE_CODE (arg0) == LSHIFT_EXPR)
- && (TREE_CODE (arg1) == RSHIFT_EXPR
- || TREE_CODE (arg1) == LSHIFT_EXPR)
- && TREE_CODE (arg0) != TREE_CODE (arg1)
+ code0 = TREE_CODE (arg0);
+ code1 = TREE_CODE (arg1);
+ if (((code0 == RSHIFT_EXPR && code1 == LSHIFT_EXPR)
+ || (code1 == RSHIFT_EXPR && code0 == LSHIFT_EXPR))
&& operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1,0), 0)
- && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg0, 0)))
- && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
- && TREE_CODE (TREE_OPERAND (arg1, 1)) == INTEGER_CST
- && TREE_INT_CST_HIGH (TREE_OPERAND (arg0, 1)) == 0
- && TREE_INT_CST_HIGH (TREE_OPERAND (arg1, 1)) == 0
- && ((TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1))
- + TREE_INT_CST_LOW (TREE_OPERAND (arg1, 1)))
+ && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg0, 0))))
+ {
+ register tree tree01, tree11;
+ register enum tree_code code01, code11;
+
+ tree01 = TREE_OPERAND (arg0, 1);
+ tree11 = TREE_OPERAND (arg1, 1);
+ code01 = TREE_CODE (tree01);
+ code11 = TREE_CODE (tree11);
+ if (code01 == INTEGER_CST
+ && code11 == INTEGER_CST
+ && TREE_INT_CST_HIGH (tree01) == 0
+ && TREE_INT_CST_HIGH (tree11) == 0
+ && ((TREE_INT_CST_LOW (tree01) + TREE_INT_CST_LOW (tree11))
== TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0)))))
- return build (LROTATE_EXPR, type, TREE_OPERAND (arg0, 0),
- TREE_CODE (arg0) == LSHIFT_EXPR
- ? TREE_OPERAND (arg0, 1) : TREE_OPERAND (arg1, 1));
+ return build (LROTATE_EXPR, type, TREE_OPERAND (arg0, 0),
+ code0 == LSHIFT_EXPR ? tree01 : tree11);
+ else if (code11 == MINUS_EXPR
+ && TREE_CODE (TREE_OPERAND (tree11, 0)) == INTEGER_CST
+ && TREE_INT_CST_HIGH (TREE_OPERAND (tree11, 0)) == 0
+ && TREE_INT_CST_LOW (TREE_OPERAND (tree11, 0))
+ == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0)))
+ && operand_equal_p (tree01, TREE_OPERAND (tree11, 1), 0))
+ return build (code0 == LSHIFT_EXPR ? LROTATE_EXPR : RROTATE_EXPR,
+ type, TREE_OPERAND (arg0, 0), tree01);
+ else if (code01 == MINUS_EXPR
+ && TREE_CODE (TREE_OPERAND (tree01, 0)) == INTEGER_CST
+ && TREE_INT_CST_HIGH (TREE_OPERAND (tree01, 0)) == 0
+ && TREE_INT_CST_LOW (TREE_OPERAND (tree01, 0))
+ == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0)))
+ && operand_equal_p (tree11, TREE_OPERAND (tree01, 1), 0))
+ return build (code0 != LSHIFT_EXPR ? LROTATE_EXPR : RROTATE_EXPR,
+ type, TREE_OPERAND (arg0, 0), tree11);
+ }
goto associate;
+ }
case BIT_XOR_EXPR:
if (integer_zerop (arg1))
}
goto binary;
+ case RDIV_EXPR:
+ /* In most cases, do nothing with a divide by zero. */
+#if !defined (REAL_IS_NOT_DOUBLE) || defined (REAL_ARITHMETIC)
+#ifndef REAL_INFINITY
+ if (TREE_CODE (arg1) == REAL_CST && real_zerop (arg1))
+ return t;
+#endif
+#endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */
+
+ /* In IEEE floating point, x/1 is not equivalent to x for snans.
+ However, ANSI says we can drop signals, so we can do this anyway. */
+ if (real_onep (arg1))
+ return non_lvalue (convert (type, arg0));
+
+ /* If ARG1 is a constant, we can convert this to a multiply by the
+ reciprocal. This does not have the same rounding properties,
+ so only do this if -ffast-math. We can actually always safely
+ do it if ARG1 is a power of two, but it's hard to tell if it is
+ or not in a portable manner. */
+ if (TREE_CODE (arg1) == REAL_CST && flag_fast_math
+ && 0 != (tem = const_binop (code, build_real (type, dconst1),
+ arg1, 0)))
+ return fold (build (MULT_EXPR, type, arg0, tem));
+
+ goto binary;
+
case TRUNC_DIV_EXPR:
case ROUND_DIV_EXPR:
case FLOOR_DIV_EXPR:
case CEIL_DIV_EXPR:
case EXACT_DIV_EXPR:
- case RDIV_EXPR:
if (integer_onep (arg1))
return non_lvalue (convert (type, arg0));
if (integer_zerop (arg1))
return t;
+ /* If we have ((a / C1) / C2) where both division are the same type, try
+ to simplify. First see if C1 * C2 overflows or not. */
+ if (TREE_CODE (arg0) == code && TREE_CODE (arg1) == INTEGER_CST
+ && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
+ {
+ tree new_divisor;
+
+ new_divisor = const_binop (MULT_EXPR, TREE_OPERAND (arg0, 1), arg1, 0);
+ tem = const_binop (FLOOR_DIV_EXPR, new_divisor, arg1, 0);
+
+ if (TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1)) == TREE_INT_CST_LOW (tem)
+ && TREE_INT_CST_HIGH (TREE_OPERAND (arg0, 1)) == TREE_INT_CST_HIGH (tem))
+ {
+ /* If no overflow, divide by C1*C2. */
+ return fold (build (code, type, TREE_OPERAND (arg0, 0), new_divisor));
+ }
+ }
+
/* Look for ((a * C1) / C3) or (((a * C1) + C2) / C3),
where C1 % C3 == 0 or C3 % C1 == 0. We can simplify these
expressions, which often appear in the offsets or sizes of
objects with a varying size. Only deal with positive divisors
- and multiplicands.
+ and multiplicands. If C2 is negative, we must have C2 % C3 == 0.
Look for NOPs and SAVE_EXPRs inside. */
if (TREE_CODE (arg1) == INTEGER_CST
- && tree_int_cst_lt (integer_zero_node, arg1))
+ && tree_int_cst_sgn (arg1) >= 0)
{
int have_save_expr = 0;
tree c2 = integer_zero_node;
tree xarg0 = arg0;
- if (TREE_CODE (xarg0) == SAVE_EXPR)
+ if (TREE_CODE (xarg0) == SAVE_EXPR && SAVE_EXPR_RTL (xarg0) == 0)
have_save_expr = 1, xarg0 = TREE_OPERAND (xarg0, 0);
STRIP_NOPS (xarg0);
&& TREE_CODE (TREE_OPERAND (xarg0, 1)) == INTEGER_CST)
c2 = TREE_OPERAND (xarg0, 1), xarg0 = TREE_OPERAND (xarg0, 0);
else if (TREE_CODE (xarg0) == MINUS_EXPR
- && TREE_CODE (TREE_OPERAND (xarg0, 1)) == INTEGER_CST)
+ && TREE_CODE (TREE_OPERAND (xarg0, 1)) == INTEGER_CST
+ /* If we are doing this computation unsigned, the negate
+ is incorrect. */
+ && ! TREE_UNSIGNED (type))
{
c2 = fold (build1 (NEGATE_EXPR, type, TREE_OPERAND (xarg0, 1)));
xarg0 = TREE_OPERAND (xarg0, 0);
}
- if (TREE_CODE (xarg0) == SAVE_EXPR)
+ if (TREE_CODE (xarg0) == SAVE_EXPR && SAVE_EXPR_RTL (xarg0) == 0)
have_save_expr = 1, xarg0 = TREE_OPERAND (xarg0, 0);
STRIP_NOPS (xarg0);
if (TREE_CODE (xarg0) == MULT_EXPR
&& TREE_CODE (TREE_OPERAND (xarg0, 1)) == INTEGER_CST
- && tree_int_cst_lt (integer_zero_node, TREE_OPERAND (xarg0, 1))
+ && tree_int_cst_sgn (TREE_OPERAND (xarg0, 1)) >= 0
&& (integer_zerop (const_binop (TRUNC_MOD_EXPR,
TREE_OPERAND (xarg0, 1), arg1, 1))
|| integer_zerop (const_binop (TRUNC_MOD_EXPR, arg1,
- TREE_OPERAND (xarg0, 1), 1))))
+ TREE_OPERAND (xarg0, 1), 1)))
+ && (tree_int_cst_sgn (c2) >= 0
+ || integer_zerop (const_binop (TRUNC_MOD_EXPR, c2,
+ arg1, 1))))
{
tree outer_div = integer_one_node;
tree c1 = TREE_OPERAND (xarg0, 1);
const_binop (code, c2, c3, 1)));
if (! integer_onep (outer_div))
- t = fold (build (code, type, t, outer_div));
+ t = fold (build (code, type, t, convert (type, outer_div)));
if (have_save_expr)
t = save_expr (t);
}
}
-#if !defined (REAL_IS_NOT_DOUBLE) || defined (REAL_ARITHMETIC)
-#ifndef REAL_INFINITY
- if (TREE_CODE (arg1) == REAL_CST
- && real_zerop (arg1))
- return t;
-#endif
-#endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */
-
goto binary;
case CEIL_MOD_EXPR:
&& TREE_CODE (TREE_OPERAND (xarg0, 1)) == INTEGER_CST)
c2 = TREE_OPERAND (xarg0, 1), xarg0 = TREE_OPERAND (xarg0, 0);
else if (TREE_CODE (xarg0) == MINUS_EXPR
- && TREE_CODE (TREE_OPERAND (xarg0, 1)) == INTEGER_CST)
+ && TREE_CODE (TREE_OPERAND (xarg0, 1)) == INTEGER_CST
+ && ! TREE_UNSIGNED (type))
{
c2 = fold (build1 (NEGATE_EXPR, type, TREE_OPERAND (xarg0, 1)));
xarg0 = TREE_OPERAND (xarg0, 0);
&& TREE_CODE (TREE_OPERAND (xarg0, 1)) == INTEGER_CST
&& integer_zerop (const_binop (TRUNC_MOD_EXPR,
TREE_OPERAND (xarg0, 1),
- arg1, 1)))
+ arg1, 1))
+ && tree_int_cst_sgn (c2) >= 0)
/* The result is (C2%C3). */
return omit_one_operand (type, const_binop (code, c2, arg1, 1),
TREE_OPERAND (xarg0, 0));
return non_lvalue (convert (type, arg0));
/* Since negative shift count is not well-defined,
don't try to compute it in the compiler. */
- if (tree_int_cst_lt (arg1, integer_zero_node))
+ if (TREE_CODE (arg1) == INTEGER_CST && tree_int_cst_sgn (arg1) < 0)
return t;
+ /* Rewrite an LROTATE_EXPR by a constant into an
+ RROTATE_EXPR by a new constant. */
+ if (code == LROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST)
+ {
+ TREE_SET_CODE (t, RROTATE_EXPR);
+ code = RROTATE_EXPR;
+ TREE_OPERAND (t, 1) = arg1
+ = const_binop
+ (MINUS_EXPR,
+ convert (TREE_TYPE (arg1),
+ build_int_2 (GET_MODE_BITSIZE (TYPE_MODE (type)), 0)),
+ arg1, 0);
+ if (tree_int_cst_sgn (arg1) < 0)
+ return t;
+ }
+
+ /* If we have a rotate of a bit operation with the rotate count and
+ the second operand of the bit operation both constant,
+ permute the two operations. */
+ if (code == RROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST
+ && (TREE_CODE (arg0) == BIT_AND_EXPR
+ || TREE_CODE (arg0) == BIT_ANDTC_EXPR
+ || TREE_CODE (arg0) == BIT_IOR_EXPR
+ || TREE_CODE (arg0) == BIT_XOR_EXPR)
+ && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
+ return fold (build (TREE_CODE (arg0), type,
+ fold (build (code, type,
+ TREE_OPERAND (arg0, 0), arg1)),
+ fold (build (code, type,
+ TREE_OPERAND (arg0, 1), arg1))));
+
+ /* Two consecutive rotates adding up to the width of the mode can
+ be ignored. */
+ if (code == RROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST
+ && TREE_CODE (arg0) == RROTATE_EXPR
+ && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
+ && TREE_INT_CST_HIGH (arg1) == 0
+ && TREE_INT_CST_HIGH (TREE_OPERAND (arg0, 1)) == 0
+ && ((TREE_INT_CST_LOW (arg1)
+ + TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1)))
+ == GET_MODE_BITSIZE (TYPE_MODE (type))))
+ return TREE_OPERAND (arg0, 0);
+
goto binary;
case MIN_EXPR:
and its values must be 0 or 1.
("true" is a fixed value perhaps depending on the language,
but we don't handle values other than 1 correctly yet.) */
- return invert_truthvalue (arg0);
+ tem = invert_truthvalue (arg0);
+ /* Avoid infinite recursion. */
+ if (TREE_CODE (tem) == TRUTH_NOT_EXPR)
+ return t;
+ return convert (type, tem);
case TRUTH_ANDIF_EXPR:
/* Note that the operands of this must be ints
return omit_one_operand (type, arg1, arg0);
truth_andor:
+ /* We only do these simplifications if we are optimizing. */
+ if (!optimize)
+ return t;
+
+ /* Check for things like (A || B) && (A || C). We can convert this
+ to A || (B && C). Note that either operator can be any of the four
+ truth and/or operations and the transformation will still be
+ valid. Also note that we only care about order for the
+ ANDIF and ORIF operators. */
+ if (TREE_CODE (arg0) == TREE_CODE (arg1)
+ && (TREE_CODE (arg0) == TRUTH_ANDIF_EXPR
+ || TREE_CODE (arg0) == TRUTH_ORIF_EXPR
+ || TREE_CODE (arg0) == TRUTH_AND_EXPR
+ || TREE_CODE (arg0) == TRUTH_OR_EXPR))
+ {
+ tree a00 = TREE_OPERAND (arg0, 0);
+ tree a01 = TREE_OPERAND (arg0, 1);
+ tree a10 = TREE_OPERAND (arg1, 0);
+ tree a11 = TREE_OPERAND (arg1, 1);
+ int commutative = ((TREE_CODE (arg0) == TRUTH_OR_EXPR
+ || TREE_CODE (arg0) == TRUTH_AND_EXPR)
+ && (code == TRUTH_AND_EXPR
+ || code == TRUTH_OR_EXPR));
+
+ if (operand_equal_p (a00, a10, 0))
+ return fold (build (TREE_CODE (arg0), type, a00,
+ fold (build (code, type, a01, a11))));
+ else if (commutative && operand_equal_p (a00, a11, 0))
+ return fold (build (TREE_CODE (arg0), type, a00,
+ fold (build (code, type, a01, a10))));
+ else if (commutative && operand_equal_p (a01, a10, 0))
+ return fold (build (TREE_CODE (arg0), type, a01,
+ fold (build (code, type, a00, a11))));
+
+ /* This case if tricky because we must either have commutative
+ operators or else A10 must not have side-effects. */
+
+ else if ((commutative || ! TREE_SIDE_EFFECTS (a10))
+ && operand_equal_p (a01, a11, 0))
+ return fold (build (TREE_CODE (arg0), type,
+ fold (build (code, type, a00, a10)),
+ a01));
+ }
+
/* Check for the possibility of merging component references. If our
lhs is another similar operation, try to merge its rhs with our
rhs. Then try to merge our lhs and rhs. */
- if (optimize)
- {
- if (TREE_CODE (arg0) == code)
- {
- tem = fold_truthop (code, type,
- TREE_OPERAND (arg0, 1), arg1);
- if (tem)
- return fold (build (code, type, TREE_OPERAND (arg0, 0), tem));
- }
+ if (TREE_CODE (arg0) == code
+ && 0 != (tem = fold_truthop (code, type,
+ TREE_OPERAND (arg0, 1), arg1)))
+ return fold (build (code, type, TREE_OPERAND (arg0, 0), tem));
+
+ if ((tem = fold_truthop (code, type, arg0, arg1)) != 0)
+ return tem;
- tem = fold_truthop (code, type, arg0, arg1);
- if (tem)
- return tem;
- }
return t;
case TRUTH_ORIF_EXPR:
and the other one. */
{
tree constop = 0, varop;
- tree *constoploc;
+ int constopnum = -1;
if (TREE_CONSTANT (arg1))
- constoploc = &TREE_OPERAND (t, 1), constop = arg1, varop = arg0;
+ constopnum = 1, constop = arg1, varop = arg0;
if (TREE_CONSTANT (arg0))
- constoploc = &TREE_OPERAND (t, 0), constop = arg0, varop = arg1;
+ constopnum = 0, constop = arg0, varop = arg1;
if (constop && TREE_CODE (varop) == POSTINCREMENT_EXPR)
{
= fold (build (PLUS_EXPR, TREE_TYPE (varop),
constop, TREE_OPERAND (varop, 1)));
TREE_SET_CODE (varop, PREINCREMENT_EXPR);
- *constoploc = newconst;
+
+ t = build (code, type, TREE_OPERAND (t, 0),
+ TREE_OPERAND (t, 1));
+ TREE_OPERAND (t, constopnum) = newconst;
return t;
}
}
= fold (build (MINUS_EXPR, TREE_TYPE (varop),
constop, TREE_OPERAND (varop, 1)));
TREE_SET_CODE (varop, PREDECREMENT_EXPR);
- *constoploc = newconst;
+ t = build (code, type, TREE_OPERAND (t, 0),
+ TREE_OPERAND (t, 1));
+ TREE_OPERAND (t, constopnum) = newconst;
return t;
}
}
/* Change X >= CST to X > (CST - 1) if CST is positive. */
if (TREE_CODE (arg1) == INTEGER_CST
&& TREE_CODE (arg0) != INTEGER_CST
- && ! tree_int_cst_lt (arg1, integer_one_node))
+ && tree_int_cst_sgn (arg1) > 0)
{
switch (TREE_CODE (t))
{
case GE_EXPR:
code = GT_EXPR;
- TREE_SET_CODE (t, code);
arg1 = const_binop (MINUS_EXPR, arg1, integer_one_node, 0);
- TREE_OPERAND (t, 1) = arg1;
+ t = build (code, type, TREE_OPERAND (t, 0), arg1);
break;
case LT_EXPR:
code = LE_EXPR;
- TREE_SET_CODE (t, code);
arg1 = const_binop (MINUS_EXPR, arg1, integer_one_node, 0);
- TREE_OPERAND (t, 1) = arg1;
+ t = build (code, type, TREE_OPERAND (t, 0), arg1);
+ break;
}
}
}
/* If this is an NE or EQ comparison of zero against the result of a
- signed MOD operation, make the MOD operation unsigned since it
- is simpler and equivalent. */
+ signed MOD operation whose second operand is a power of 2, make
+ the MOD operation unsigned since it is simpler and equivalent. */
if ((code == NE_EXPR || code == EQ_EXPR)
&& integer_zerop (arg1)
&& ! TREE_UNSIGNED (TREE_TYPE (arg0))
&& (TREE_CODE (arg0) == TRUNC_MOD_EXPR
|| TREE_CODE (arg0) == CEIL_MOD_EXPR
|| TREE_CODE (arg0) == FLOOR_MOD_EXPR
- || TREE_CODE (arg0) == ROUND_MOD_EXPR))
+ || TREE_CODE (arg0) == ROUND_MOD_EXPR)
+ && integer_pow2p (TREE_OPERAND (arg0, 1)))
{
tree newtype = unsigned_type (TREE_TYPE (arg0));
tree newmod = build (TREE_CODE (arg0), newtype,
return build (code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type,
arg0, integer_zero_node);
+ /* If X is unsigned, convert X < (1 << Y) into X >> Y == 0
+ and similarly for >= into !=. */
+ if ((code == LT_EXPR || code == GE_EXPR)
+ && TREE_UNSIGNED (TREE_TYPE (arg0))
+ && TREE_CODE (arg1) == LSHIFT_EXPR
+ && integer_onep (TREE_OPERAND (arg1, 0)))
+ return build (code == LT_EXPR ? EQ_EXPR : NE_EXPR, type,
+ build (RSHIFT_EXPR, TREE_TYPE (arg0), arg0,
+ TREE_OPERAND (arg1, 1)),
+ convert (TREE_TYPE (arg0), integer_zero_node));
+
+ else if ((code == LT_EXPR || code == GE_EXPR)
+ && TREE_UNSIGNED (TREE_TYPE (arg0))
+ && (TREE_CODE (arg1) == NOP_EXPR
+ || TREE_CODE (arg1) == CONVERT_EXPR)
+ && TREE_CODE (TREE_OPERAND (arg1, 0)) == LSHIFT_EXPR
+ && integer_onep (TREE_OPERAND (TREE_OPERAND (arg1, 0), 0)))
+ return
+ build (code == LT_EXPR ? EQ_EXPR : NE_EXPR, type,
+ convert (TREE_TYPE (arg0),
+ build (RSHIFT_EXPR, TREE_TYPE (arg0), arg0,
+ TREE_OPERAND (TREE_OPERAND (arg1, 0), 1))),
+ convert (TREE_TYPE (arg0), integer_zero_node));
+
/* Simplify comparison of something with itself. (For IEEE
floating-point, we can only do some of these simplifications.) */
if (operand_equal_p (arg0, arg1, 0))
if (TREE_CODE (arg1) == INTEGER_CST && TREE_CODE (arg0) != INTEGER_CST)
{
tree cval1 = 0, cval2 = 0;
+ int save_p = 0;
- if (twoval_comparison_p (arg0, &cval1, &cval2)
+ if (twoval_comparison_p (arg0, &cval1, &cval2, &save_p)
/* Don't handle degenerate cases here; they should already
have been handled anyway. */
&& cval1 != 0 && cval2 != 0
return omit_one_operand (type, integer_one_node, arg0);
}
- return fold (build (code, type, cval1, cval2));
+ t = build (code, type, cval1, cval2);
+ if (save_p)
+ return save_expr (t);
+ else
+ return fold (t);
}
}
}
return t1 ? t1 : t;
}
+ /* If this is a comparison of complex values and either or both
+ sizes are a COMPLEX_EXPR, it is best to split up the comparisons
+ and join them with a TRUTH_ANDIF_EXPR or TRUTH_ORIF_EXPR. This
+ may prevent needless evaluations. */
+ if ((code == EQ_EXPR || code == NE_EXPR)
+ && TREE_CODE (TREE_TYPE (arg0)) == COMPLEX_TYPE
+ && (TREE_CODE (arg0) == COMPLEX_EXPR
+ || TREE_CODE (arg1) == COMPLEX_EXPR))
+ {
+ tree subtype = TREE_TYPE (TREE_TYPE (arg0));
+ tree real0 = fold (build1 (REALPART_EXPR, subtype, arg0));
+ tree imag0 = fold (build1 (IMAGPART_EXPR, subtype, arg0));
+ tree real1 = fold (build1 (REALPART_EXPR, subtype, arg1));
+ tree imag1 = fold (build1 (IMAGPART_EXPR, subtype, arg1));
+
+ return fold (build ((code == EQ_EXPR ? TRUTH_ANDIF_EXPR
+ : TRUTH_ORIF_EXPR),
+ type,
+ fold (build (code, type, real0, real1)),
+ fold (build (code, type, imag0, imag1))));
+ }
+
/* From here on, the only cases we handle are when the result is
known to be a constant.
return pedantic_non_lvalue
(TREE_OPERAND (t, (integer_zerop (arg0) ? 2 : 1)));
else if (operand_equal_p (arg1, TREE_OPERAND (expr, 2), 0))
- return pedantic_non_lvalue (omit_one_operand (type, arg1, arg0));
+ return pedantic_omit_one_operand (type, arg1, arg0);
/* If the second operand is zero, invert the comparison and swap
the second and third operands. Likewise if the second operand
if (TREE_CODE (tem) != TRUTH_NOT_EXPR)
{
- arg0 = TREE_OPERAND (t, 0) = tem;
- TREE_OPERAND (t, 1) = TREE_OPERAND (t, 2);
- TREE_OPERAND (t, 2) = arg1;
- arg1 = TREE_OPERAND (t, 1);
+ t = build (code, type, tem,
+ TREE_OPERAND (t, 2), TREE_OPERAND (t, 1));
+ arg0 = tem;
+ arg1 = TREE_OPERAND (t, 2);
+ STRIP_NOPS (arg1);
}
}
if (TREE_CODE_CLASS (TREE_CODE (arg0)) == '<'
&& (TARGET_FLOAT_FORMAT != IEEE_FLOAT_FORMAT
- || ! FLOAT_TYPE_P (TREE_TYPE (TREE_OPERAND (arg0, 0))))
+ || ! FLOAT_TYPE_P (TREE_TYPE (TREE_OPERAND (arg0, 0)))
+ || flag_fast_math)
&& operand_equal_for_comparison_p (TREE_OPERAND (arg0, 0),
arg1, TREE_OPERAND (arg0, 1)))
{
tree arg2 = TREE_OPERAND (t, 2);
enum tree_code comp_code = TREE_CODE (arg0);
+ STRIP_NOPS (arg2);
+
/* If we have A op 0 ? A : -A, this is A, -A, abs (A), or abs (-A),
depending on the comparison operation. */
- if (integer_zerop (TREE_OPERAND (arg0, 1))
+ if ((FLOAT_TYPE_P (TREE_TYPE (TREE_OPERAND (arg0, 1)))
+ ? real_zerop (TREE_OPERAND (arg0, 1))
+ : integer_zerop (TREE_OPERAND (arg0, 1)))
&& TREE_CODE (arg2) == NEGATE_EXPR
&& operand_equal_p (TREE_OPERAND (arg2, 0), arg1, 0))
switch (comp_code)
case GE_EXPR:
case GT_EXPR:
return pedantic_non_lvalue
- (fold (build1 (ABS_EXPR, type, arg1)));
+ (convert (type, fold (build1 (ABS_EXPR,
+ TREE_TYPE (arg1), arg1))));
case LE_EXPR:
case LT_EXPR:
return pedantic_non_lvalue
(fold (build1 (NEGATE_EXPR, type,
- fold (build1 (ABS_EXPR, type, arg1)))));
+ convert (type,
+ fold (build1 (ABS_EXPR,
+ TREE_TYPE (arg1),
+ arg1))))));
}
/* If this is A != 0 ? A : 0, this is simply A. For ==, it is
if (operand_equal_for_comparison_p (TREE_OPERAND (arg0, 1),
arg2, TREE_OPERAND (arg0, 0)))
- switch (comp_code)
- {
- case EQ_EXPR:
- return pedantic_non_lvalue (convert (type, arg2));
- case NE_EXPR:
- return pedantic_non_lvalue (convert (type, arg1));
- case LE_EXPR:
- case LT_EXPR:
- return pedantic_non_lvalue
- (fold (build (MIN_EXPR, type, arg1, arg2)));
- case GE_EXPR:
- case GT_EXPR:
- return pedantic_non_lvalue
- (fold (build (MAX_EXPR, type, arg1, arg2)));
- }
+ {
+ tree comp_op0 = TREE_OPERAND (arg0, 0);
+ tree comp_op1 = TREE_OPERAND (arg0, 1);
+ tree comp_type = TREE_TYPE (comp_op0);
+
+ switch (comp_code)
+ {
+ case EQ_EXPR:
+ return pedantic_non_lvalue (convert (type, arg2));
+ case NE_EXPR:
+ return pedantic_non_lvalue (convert (type, arg1));
+ case LE_EXPR:
+ case LT_EXPR:
+ return pedantic_non_lvalue
+ (convert (type, (fold (build (MIN_EXPR, comp_type,
+ comp_op0, comp_op1)))));
+ case GE_EXPR:
+ case GT_EXPR:
+ return pedantic_non_lvalue
+ (convert (type, fold (build (MAX_EXPR, comp_type,
+ comp_op0, comp_op1))));
+ }
+ }
/* If this is A op C1 ? A : C2 with C1 and C2 constant integers,
we might still be able to simplify this. For example,
{
case EQ_EXPR:
/* We can replace A with C1 in this case. */
- arg1 = TREE_OPERAND (t, 1)
- = convert (type, TREE_OPERAND (arg0, 1));
+ arg1 = convert (type, TREE_OPERAND (arg0, 1));
+ t = build (code, type, TREE_OPERAND (t, 0), arg1,
+ TREE_OPERAND (t, 2));
break;
case LT_EXPR:
}
}
+ /* If the second operand is simpler than the third, swap them
+ since that produces better jump optimization results. */
+ if ((TREE_CONSTANT (arg1) || TREE_CODE_CLASS (TREE_CODE (arg1)) == 'd'
+ || TREE_CODE (arg1) == SAVE_EXPR)
+ && ! (TREE_CONSTANT (TREE_OPERAND (t, 2))
+ || TREE_CODE_CLASS (TREE_CODE (TREE_OPERAND (t, 2))) == 'd'
+ || TREE_CODE (TREE_OPERAND (t, 2)) == SAVE_EXPR))
+ {
+ /* See if this can be inverted. If it can't, possibly because
+ it was a floating-point inequality comparison, don't do
+ anything. */
+ tem = invert_truthvalue (arg0);
+
+ if (TREE_CODE (tem) != TRUTH_NOT_EXPR)
+ {
+ t = build (code, type, tem,
+ TREE_OPERAND (t, 2), TREE_OPERAND (t, 1));
+ arg0 = tem;
+ arg1 = TREE_OPERAND (t, 2);
+ STRIP_NOPS (arg1);
+ }
+ }
+
/* Convert A ? 1 : 0 to simply A. */
if (integer_onep (TREE_OPERAND (t, 1))
&& integer_zerop (TREE_OPERAND (t, 2))
&& type == TREE_TYPE (arg0))
return pedantic_non_lvalue (arg0);
-
/* Look for expressions of the form A & 2 ? 2 : 0. The result of this
operation is simply A & 2. */
TREE_OPERAND (arg0, 1)))));
return t;
+ /* Pull arithmetic ops out of the CLEANUP_POINT_EXPR where
+ appropriate. */
+ case CLEANUP_POINT_EXPR:
+ if (! TREE_SIDE_EFFECTS (arg0))
+ return convert (type, arg0);
+
+ {
+ enum tree_code code0 = TREE_CODE (arg0);
+ int kind0 = TREE_CODE_CLASS (code0);
+ tree arg00 = TREE_OPERAND (arg0, 0);
+ tree arg01;
+
+ if (kind0 == '1' || code0 == TRUTH_NOT_EXPR)
+ return fold (build1 (code0, type,
+ fold (build1 (CLEANUP_POINT_EXPR,
+ TREE_TYPE (arg00), arg00))));
+
+ if (kind0 == '<' || kind0 == '2'
+ || code0 == TRUTH_ANDIF_EXPR || code0 == TRUTH_ORIF_EXPR
+ || code0 == TRUTH_AND_EXPR || code0 == TRUTH_OR_EXPR
+ || code0 == TRUTH_XOR_EXPR)
+ {
+ arg01 = TREE_OPERAND (arg0, 1);
+
+ if (! TREE_SIDE_EFFECTS (arg00))
+ return fold (build (code0, type, arg00,
+ fold (build1 (CLEANUP_POINT_EXPR,
+ TREE_TYPE (arg01), arg01))));
+
+ if (! TREE_SIDE_EFFECTS (arg01))
+ return fold (build (code0, type,
+ fold (build1 (CLEANUP_POINT_EXPR,
+ TREE_TYPE (arg00), arg00)),
+ arg01));
+ }
+
+ return t;
+ }
+
default:
return t;
} /* switch (code) */
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