From 68c8845d15c652599a154c61d835dba810ef3ab0 Mon Sep 17 00:00:00 2001
From: Alex Coyte <a.coyte@intel.com>
Date: Tue, 18 Jul 2017 12:49:32 +1000
Subject: [PATCH] Do equivalency removal before violet's implementablity check.

This is helpful as removing/restoring literals may introduce redundancy in the
graphs. Also improve the implementation by caching known good holders.
---
 src/nfagraph/ng_violet.cpp | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/src/nfagraph/ng_violet.cpp b/src/nfagraph/ng_violet.cpp
index 6742fec9..e19a6211 100644
--- a/src/nfagraph/ng_violet.cpp
+++ b/src/nfagraph/ng_violet.cpp
@@ -1759,7 +1759,6 @@ void removeRedundantLiteralsFromInfixes(RoseInGraph &g,
     }
 }
 
-
 static
 void removeRedundantLiterals(RoseInGraph &g, const CompileContext &cc) {
     removeRedundantLiteralsFromPrefixes(g, cc);
@@ -2886,6 +2885,7 @@ bool ensureImplementable(RoseBuild &rose, RoseInGraph &vg, bool allow_changes,
     bool changed = false;
     bool need_to_recalc = false;
     u32 added_count = 0;
+    unordered_set<NGHolder *> good; /* known to be implementable */
     do {
         changed = false;
         DEBUG_PRINTF("added %u\n", added_count);
@@ -2901,13 +2901,19 @@ bool ensureImplementable(RoseBuild &rose, RoseInGraph &vg, bool allow_changes,
             }
         }
         for (NGHolder *h : graphs) {
+            if (contains(good, h)) {
+                continue;
+            }
+            reduceGraphEquivalences(*h, cc);
             if (isImplementableNFA(*h, &rm, cc)) {
+                good.insert(h);
                 continue;
             }
 
             if (tryForEarlyDfa(*h, cc)
                 && doEarlyDfa(rose, vg, *h, edges_by_graph[h], final_chance, rm,
                               cc)) {
+                good.insert(h);
                 continue;
             }
 
@@ -2923,6 +2929,7 @@ bool ensureImplementable(RoseBuild &rose, RoseInGraph &vg, bool allow_changes,
                     return false;
                 }
                 changed = true;
+                good.insert(h);
                 continue;
             }