diff options
Diffstat (limited to 'usr.bin/gprof/dfn.c')
-rw-r--r-- | usr.bin/gprof/dfn.c | 325 |
1 files changed, 325 insertions, 0 deletions
diff --git a/usr.bin/gprof/dfn.c b/usr.bin/gprof/dfn.c new file mode 100644 index 0000000..987929f --- /dev/null +++ b/usr.bin/gprof/dfn.c @@ -0,0 +1,325 @@ +/* + * Copyright (c) 1983, 1993 + * The Regents of the University of California. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#ifndef lint +static char sccsid[] = "@(#)dfn.c 8.1 (Berkeley) 6/6/93"; +#endif /* not lint */ + +#include <stdio.h> +#include "gprof.h" + +#define DFN_DEPTH 100 +struct dfnstruct { + nltype *nlentryp; + int cycletop; +}; +typedef struct dfnstruct dfntype; + +dfntype dfn_stack[ DFN_DEPTH ]; +int dfn_depth; + +int dfn_counter; + +dfn_init() +{ + + dfn_depth = 0; + dfn_counter = DFN_NAN; +} + + /* + * given this parent, depth first number its children. + */ +dfn( parentp ) + nltype *parentp; +{ + arctype *arcp; + +# ifdef DEBUG + if ( debug & DFNDEBUG ) { + printf( "[dfn] dfn(" ); + printname( parentp ); + printf( ")\n" ); + } +# endif DEBUG + /* + * if we're already numbered, no need to look any furthur. + */ + if ( dfn_numbered( parentp ) ) { + return; + } + /* + * if we're already busy, must be a cycle + */ + if ( dfn_busy( parentp ) ) { + dfn_findcycle( parentp ); + return; + } + /* + * visit yourself before your children + */ + dfn_pre_visit( parentp ); + /* + * visit children + */ + for ( arcp = parentp -> children ; arcp ; arcp = arcp -> arc_childlist ) { + if ( arcp -> arc_flags & DEADARC ) + continue; + dfn( arcp -> arc_childp ); + } + /* + * visit yourself after your children + */ + dfn_post_visit( parentp ); +} + + /* + * push a parent onto the stack and mark it busy + */ +dfn_pre_visit( parentp ) + nltype *parentp; +{ + + dfn_depth += 1; + if ( dfn_depth >= DFN_DEPTH ) { + fprintf( stderr , "[dfn] out of my depth (dfn_stack overflow)\n" ); + exit( 1 ); + } + dfn_stack[ dfn_depth ].nlentryp = parentp; + dfn_stack[ dfn_depth ].cycletop = dfn_depth; + parentp -> toporder = DFN_BUSY; +# ifdef DEBUG + if ( debug & DFNDEBUG ) { + printf( "[dfn_pre_visit]\t\t%d:" , dfn_depth ); + printname( parentp ); + printf( "\n" ); + } +# endif DEBUG +} + + /* + * are we already numbered? + */ +bool +dfn_numbered( childp ) + nltype *childp; +{ + + return ( childp -> toporder != DFN_NAN && childp -> toporder != DFN_BUSY ); +} + + /* + * are we already busy? + */ +bool +dfn_busy( childp ) + nltype *childp; +{ + + if ( childp -> toporder == DFN_NAN ) { + return FALSE; + } + return TRUE; +} + + /* + * MISSING: an explanation + */ +dfn_findcycle( childp ) + nltype *childp; +{ + int cycletop; + nltype *cycleheadp; + nltype *tailp; + int index; + + for ( cycletop = dfn_depth ; cycletop > 0 ; cycletop -= 1 ) { + cycleheadp = dfn_stack[ cycletop ].nlentryp; + if ( childp == cycleheadp ) { + break; + } + if ( childp -> cyclehead != childp && + childp -> cyclehead == cycleheadp ) { + break; + } + } + if ( cycletop <= 0 ) { + fprintf( stderr , "[dfn_findcycle] couldn't find head of cycle\n" ); + exit( 1 ); + } +# ifdef DEBUG + if ( debug & DFNDEBUG ) { + printf( "[dfn_findcycle] dfn_depth %d cycletop %d " , + dfn_depth , cycletop ); + printname( cycleheadp ); + printf( "\n" ); + } +# endif DEBUG + if ( cycletop == dfn_depth ) { + /* + * this is previous function, e.g. this calls itself + * sort of boring + */ + dfn_self_cycle( childp ); + } else { + /* + * glom intervening functions that aren't already + * glommed into this cycle. + * things have been glommed when their cyclehead field + * points to the head of the cycle they are glommed into. + */ + for ( tailp = cycleheadp ; tailp -> cnext ; tailp = tailp -> cnext ) { + /* void: chase down to tail of things already glommed */ +# ifdef DEBUG + if ( debug & DFNDEBUG ) { + printf( "[dfn_findcycle] tail " ); + printname( tailp ); + printf( "\n" ); + } +# endif DEBUG + } + /* + * if what we think is the top of the cycle + * has a cyclehead field, then it's not really the + * head of the cycle, which is really what we want + */ + if ( cycleheadp -> cyclehead != cycleheadp ) { + cycleheadp = cycleheadp -> cyclehead; +# ifdef DEBUG + if ( debug & DFNDEBUG ) { + printf( "[dfn_findcycle] new cyclehead " ); + printname( cycleheadp ); + printf( "\n" ); + } +# endif DEBUG + } + for ( index = cycletop + 1 ; index <= dfn_depth ; index += 1 ) { + childp = dfn_stack[ index ].nlentryp; + if ( childp -> cyclehead == childp ) { + /* + * not yet glommed anywhere, glom it + * and fix any children it has glommed + */ + tailp -> cnext = childp; + childp -> cyclehead = cycleheadp; +# ifdef DEBUG + if ( debug & DFNDEBUG ) { + printf( "[dfn_findcycle] glomming " ); + printname( childp ); + printf( " onto " ); + printname( cycleheadp ); + printf( "\n" ); + } +# endif DEBUG + for ( tailp = childp ; tailp->cnext ; tailp = tailp->cnext ) { + tailp -> cnext -> cyclehead = cycleheadp; +# ifdef DEBUG + if ( debug & DFNDEBUG ) { + printf( "[dfn_findcycle] and its tail " ); + printname( tailp -> cnext ); + printf( " onto " ); + printname( cycleheadp ); + printf( "\n" ); + } +# endif DEBUG + } + } else if ( childp -> cyclehead != cycleheadp /* firewall */ ) { + fprintf( stderr , + "[dfn_busy] glommed, but not to cyclehead\n" ); + } + } + } +} + + /* + * deal with self-cycles + * for lint: ARGSUSED + */ +dfn_self_cycle( parentp ) + nltype *parentp; +{ + /* + * since we are taking out self-cycles elsewhere + * no need for the special case, here. + */ +# ifdef DEBUG + if ( debug & DFNDEBUG ) { + printf( "[dfn_self_cycle] " ); + printname( parentp ); + printf( "\n" ); + } +# endif DEBUG +} + + /* + * visit a node after all its children + * [MISSING: an explanation] + * and pop it off the stack + */ +dfn_post_visit( parentp ) + nltype *parentp; +{ + nltype *memberp; + +# ifdef DEBUG + if ( debug & DFNDEBUG ) { + printf( "[dfn_post_visit]\t%d: " , dfn_depth ); + printname( parentp ); + printf( "\n" ); + } +# endif DEBUG + /* + * number functions and things in their cycles + * unless the function is itself part of a cycle + */ + if ( parentp -> cyclehead == parentp ) { + dfn_counter += 1; + for ( memberp = parentp ; memberp ; memberp = memberp -> cnext ) { + memberp -> toporder = dfn_counter; +# ifdef DEBUG + if ( debug & DFNDEBUG ) { + printf( "[dfn_post_visit]\t\tmember " ); + printname( memberp ); + printf( " -> toporder = %d\n" , dfn_counter ); + } +# endif DEBUG + } + } else { +# ifdef DEBUG + if ( debug & DFNDEBUG ) { + printf( "[dfn_post_visit]\t\tis part of a cycle\n" ); + } +# endif DEBUG + } + dfn_depth -= 1; +} |