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* src/conflicts.c (flush_shift, resolve_sr_conflict): De-obfuscate

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using the good o' techniques: arrays not pointers, variable
locality, BITISSET, RESETBIT etc.
This commit is contained in:
Akim Demaille
2001-12-05 09:20:55 +00:00
parent 19f8d30b9c
commit 32f18df511
2 changed files with 25 additions and 36 deletions
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7
ChangeLog
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@@ -1,3 +1,10 @@
2001-12-05 Akim Demaille <akim@epita.fr>
* src/conflicts.c (flush_shift, resolve_sr_conflict): De-obfuscate
using the good o' techniques: arrays not pointers, variable
locality, BITISSET, RESETBIT etc.
2001-12-05 Akim Demaille <akim@epita.fr> 2001-12-05 Akim Demaille <akim@epita.fr>
* src/state.h (SHIFT_SYMBOL): New. * src/state.h (SHIFT_SYMBOL): New.

54
src/conflicts.c
View File

@@ -57,21 +57,13 @@ Conflict in state %d between rule %d and token %s resolved as %s.\n"),
static void static void
flush_shift (int state, int token) flush_shift (int state, int token)
{ {
shifts *shiftp; shifts *shiftp = state_table[state].shift_table;
int k, i; int i;
shiftp = state_table[state].shift_table;
if (shiftp) if (shiftp)
{ for (i = 0; i < shiftp->nshifts; i++)
k = shiftp->nshifts; if (shiftp->shifts[i] && SHIFT_SYMBOL (shiftp, i) == token)
for (i = 0; i < k; i++) shiftp->shifts[i] = 0;
{
if (shiftp->shifts[i]
&& token == state_table[shiftp->shifts[i]].accessing_symbol)
(shiftp->shifts[i]) = 0;
}
}
} }
@@ -86,22 +78,16 @@ static void
resolve_sr_conflict (int state, int lookaheadnum) resolve_sr_conflict (int state, int lookaheadnum)
{ {
int i; int i;
int mask; /* find the rule to reduce by to get precedence of reduction */
unsigned *fp1; int redprec = rule_table[LAruleno[lookaheadnum]].prec;
unsigned *fp2;
int redprec;
errs *errp = ERRS_ALLOC (ntokens + 1); errs *errp = ERRS_ALLOC (ntokens + 1);
short *errtokens = errp->errs; short *errtokens = errp->errs;
/* find the rule to reduce by to get precedence of reduction */
redprec = rule_table[LAruleno[lookaheadnum]].prec;
mask = 1;
fp1 = LA (lookaheadnum);
fp2 = lookaheadset;
for (i = 0; i < ntokens; i++) for (i = 0; i < ntokens; i++)
{ {
if ((mask & *fp2 & *fp1) && sprec[i]) if (BITISSET (LA (lookaheadnum), i)
&& BITISSET (lookaheadset, i)
&& sprec[i])
/* Shift-reduce conflict occurs for token number i /* Shift-reduce conflict occurs for token number i
and it has a precedence. and it has a precedence.
The precedence of shifting is that of token i. */ The precedence of shifting is that of token i. */
@@ -109,13 +95,15 @@ resolve_sr_conflict (int state, int lookaheadnum)
if (sprec[i] < redprec) if (sprec[i] < redprec)
{ {
log_resolution (state, lookaheadnum, i, _("reduce")); log_resolution (state, lookaheadnum, i, _("reduce"));
*fp2 &= ~mask; /* flush the shift for this token */ /* flush the shift for this token */
RESETBIT (lookaheadset, i);
flush_shift (state, i); flush_shift (state, i);
} }
else if (sprec[i] > redprec) else if (sprec[i] > redprec)
{ {
log_resolution (state, lookaheadnum, i, _("shift")); log_resolution (state, lookaheadnum, i, _("shift"));
*fp1 &= ~mask; /* flush the reduce for this token */ /* flush the reduce for this token */
RESETBIT (LA (lookaheadnum), i);
} }
else else
{ {
@@ -141,12 +129,14 @@ resolve_sr_conflict (int state, int lookaheadnum)
if (sassoc[i] != right_assoc) if (sassoc[i] != right_assoc)
{ {
*fp2 &= ~mask; /* flush the shift for this token */ /* flush the shift for this token */
RESETBIT (lookaheadset, i);
flush_shift (state, i); flush_shift (state, i);
} }
if (sassoc[i] != left_assoc) if (sassoc[i] != left_assoc)
{ {
*fp1 &= ~mask; /* flush the reduce for this token */ /* flush the reduce for this token */
RESETBIT (LA (lookaheadnum), i);
} }
if (sassoc[i] == non_assoc) if (sassoc[i] == non_assoc)
{ {
@@ -155,14 +145,6 @@ resolve_sr_conflict (int state, int lookaheadnum)
} }
} }
} }
mask <<= 1;
if (mask == 0)
{
mask = 1;
fp2++;
fp1++;
}
} }
errp->nerrs = errtokens - errp->errs; errp->nerrs = errtokens - errp->errs;
if (errp->nerrs) if (errp->nerrs)