From ce572ca8818ff32738ab980b9f01f1df15796297 Mon Sep 17 00:00:00 2001
From: kostis <kostis@b08c6af1-5177-4d33-ba66-4b1c6b8b522a>
Date: Sat, 10 Mar 2007 10:52:40 +0000
Subject: [PATCH] Version with left-recursive points_to/2 predicate.

git-svn-id: https://yap.svn.sf.net/svnroot/yap/trunk@1820 b08c6af1-5177-4d33-ba66-4b1c6b8b522a
---
 docs/index/Benchmarks/pta.P | 20 +++++++++++++++++---
 1 file changed, 17 insertions(+), 3 deletions(-)

diff --git a/docs/index/Benchmarks/pta.P b/docs/index/Benchmarks/pta.P
index a453c79f4..67a513790 100644
--- a/docs/index/Benchmarks/pta.P
+++ b/docs/index/Benchmarks/pta.P
@@ -1,4 +1,15 @@
-%:- set_prolog_flag(index,single).
+/*
+** This is a benchmark that implements Andersen's Points To Analysis
+** using tabling.
+**
+** To bypass a problem in XXX the code has been slightly modified.
+** The original version used a right-recursive tabled predicate
+** for points_to/2; this version uses a left-recursive predicate.
+** Note that this gives significantly less answers, but it is a
+** tabled benchmark nonetheless.
+**/
+
+%% :- set_prolog_flag(index,single).
 %% :- yap_flag(tabling_mode, local).
 
 time :-
@@ -35,9 +46,12 @@ get_var(X) :- var(true,X).  % pointer variables
 :- table pointed_to_by/2.
 :- table aux2/2.
 
+%% ORIGINAL VERSION
+%% points_to --> fa.
+%% points_to --> aux1, points_to.
+%% 
 points_to --> fa.
-points_to(X,Y) :- points_to(Z,Y), aux1(X,Z).
-% points_to --> aux1, points_to.
+points_to --> points_to, aux1.
 
 aux1 --> f.
 aux1 --> aux11.