DECBDDREFEXT(3)

💅 DECBDDREFEXT(3) — like, the external-ref decrement one

okay so bestie, welcome to the BDD FUNCTIONS corner of the (3) manual ✨ this whole page is about decbddrefext, and it's genuinely one of the simplest little guys in the whole BDD crew, so you're gonna slay this 🎀

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🌸 ORIGIN 🌸

so this software belongs to the ALLIANCE CAD SYSTEM, built by the ASIM team at the LIP6 laboratory of Université Pierre et Marie CURIE, in Paris, France 🥖💖 (the original page renders that university name with a slightly cursed accent byte, no cap, but you get the vibe — it's Paris, it's iconic 👑)

• Web : http://asim.lip6.fr/recherche/alliance/
• E-mail : alliance-users@asim.lip6.fr

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✨ SYNOPSIS ✨

#include "bdd101.h"
bddnode ∗decbddrefext( BddNode )
  bddnode ∗BddNode;

like, you pass in one node pointer and you get a node pointer back. that's the whole plot 🫶

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🎀 PARAMETERS 🎀

• BddNode — the bdd node, obviously 💅 this is the guy whose external reference count is about to take a little dip.

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🦋 DESCRIPTION 🦋

decbddrefext decrements the number of external references on the bdd node BddNode. that's it. that's the function. she's a one-trick pony and she does her trick flawlessly ✨

think of it as "i'm done holding this node from the outside, you can let go of one of my fingers now" 🫳 lowkey the most honest function on the whole page.

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💖 RETURN VALUE 💖

decbddrefext returns the BddNode pointer. same pointer you handed in, coming right back at you like a boomerang 🪃 periodt.

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💀 ERRORS 💀

• "negative reference, index xxx error !" — dramatic but fair: the BddNode must have a positive number of external references. if you try to decrement a count that's already at zero, you get this error message and honestly, deserved 🙈 don't decrement what you didn't increment, bestie.

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🔥 EXAMPLE 🔥

okay this is the main character example, study it because it's cute:

#include "bdd101.h"
   bddsystem  ∗BddSystem;
   bddcircuit ∗BddCircuit;
   bddnode    ∗BddNode;
   chain_list ∗Expr;
   BddSystem  = createbddsystem( 100, 1000, 100, 50000 );
   BddCircuit = createbddcircuit( "hello_world", 10, 10, BddSystem );
   BddNode = addbddcircuitin( (bddcircuit ∗)0, "i0", 0, BDD_IN_MODE_FIRST );
   BddNode = addbddnode( (bddsystem ∗)0, BddNode->INDEX, BddNode->LOW, BddNode->HIGH );
   Expr = convertbddcircuitabl( (bddcircuit ∗)0, BddNode );
   decbddrefext( BddNode );
   /* displays Node VAR: 0  INDEX: 2  MARK: 0  REF_EXT: 0  REF_INT: 0 */
   viewbddnode( (bddsystem ∗)0, BddNode );
   /* displays (not i0) */
   viewablexpr( Expr, ABL_VIEW_VHDL );
   freeablexpr( Expr );
   destroybddsystem( (bddsystem ∗)0 );
   destroybddcircuit( (bddcircuit ∗)0 );

so you create a system, create a circuit called "hello_world" (iconic name, no notes 💅), make an input node, wrap it with addbddnode, convert it to an ABL expression, then — the moment we've all been waiting for — call decbddrefext( BddNode ) 🎉

after that, viewbddnode displays:

Node VAR: 0  INDEX: 2  MARK: 0  REF_EXT: 0  REF_INT: 0

like look at that REF_EXT: 0 — she ate and left zero crumbs 🔥 and viewablexpr( Expr, ABL_VIEW_VHDL ) displays:

(not i0)

then we tidy up: freeablexpr, destroybddsystem, destroybddcircuit. clean up your room bestie, always 🌸

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🧚 SEE ALSO 🧚

• bdd(1) — go read this too, iykyk

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🫶 BUG REPORT 🫶

this tool is under development at the ASIM department of the LIP6 laboratory ⭐ and fr fr, they need your feedback to improve documentation and tools. so like, if something's off, tell them 💌

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okay that's the whole page, you're a decbddrefext expert now, go decrement responsibly 💅✨

this little number comes to you from ASIM/LIP6, dated October 1, 1997 — vintage, iconic, still slaying 💖🎀