43 lines
961 B
C
43 lines
961 B
C
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// Copyright (c) 1993-1999 Microsoft Corporation
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#include "y3.h"
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void
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precftn(SSIZE_T r,int t,int s)
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{
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/* decide a shift/reduce conflict by precedence.*/
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/* r is a rule number, t a token number */
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/* the conflict is in state s */
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/* temp1[t] is changed to reflect the action */
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int lt, action;
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SSIZE_T lp;
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lp = levprd[r];
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lt = toklev[t];
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if( PLEVEL(lt) == 0 || PLEVEL(lp) == 0 )
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{
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/* conflict */
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if( foutput != NULL ) fprintf( foutput, "\n%d: shift/reduce conflict (shift %d, red'n %d) on %s",
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s, temp1[t], r, symnam(t) );
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++zzsrconf;
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return;
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}
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if( PLEVEL(lt) == PLEVEL(lp) ) action = ASSOC(lt);
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else if( PLEVEL(lt) > PLEVEL(lp) ) action = RASC; /* shift */
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else action = LASC; /* reduce */
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switch( action )
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{
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case BASC: /* error action */
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temp1[t] = ERRCODE;
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return;
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case LASC: /* reduce */
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temp1[t] = -r;
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return;
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}
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}
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