From 751932ddb10d5ce798c56d82bc1f40a443237ac1 Mon Sep 17 00:00:00 2001
From: Patrick Lam <plam@MIT.EDU>
Date: Wed, 5 Oct 2005 18:41:55 +0000
Subject: [PATCH] Implement move-to-front array for banks (perf regression
 reported by Ronny     V. Vindenes).

---
 ChangeLog     |  6 ++++++
 src/fccache.c | 29 +++++++++++++++++++----------
 2 files changed, 25 insertions(+), 10 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index b7cfb91..3bbf227 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2005-10-05  Patrick Lam  <plam@mit.edu>
+	* src/fccache.c (FcCacheHaveBank):
+
+	Implement move-to-front array for banks (perf regression
+	reported by Ronny V. Vindenes).
+
 2005-10-04  Patrick Lam  <plam@mit.edu>
 	* src/fccache.c (FcDirCacheValid, FcDirCacheUnlink, 
 	                 FcDirCacheHasCurrentArch):
diff --git a/src/fccache.c b/src/fccache.c
index 43e45af..0e8c476 100644
--- a/src/fccache.c
+++ b/src/fccache.c
@@ -949,7 +949,7 @@ FcCacheMachineSignature ()
 }
 
 static int banks_ptr = 0, banks_alloc = 0;
-static int * bankId = 0;
+static int * bankId = 0, * bankIdx = 0;
 
 static FcBool
 FcCacheHaveBank (int bank)
@@ -969,28 +969,37 @@ FcCacheHaveBank (int bank)
 int
 FcCacheBankToIndex (int bank)
 {
-    static int lastBank = FC_BANK_DYNAMIC, lastIndex = -1;
-    int i;
-    int * b;
-
-    if (bank == lastBank)
-	return lastIndex;
+    int i, j;
 
     for (i = 0; i < banks_ptr; i++)
-	if (bankId[i] == bank)
-	    return i;
+	if (bankId[bankIdx[i]] == bank)
+	{
+	    int t = bankIdx[i];
+
+	    for (j = i; j > 0; j--)
+		bankIdx[j] = bankIdx[j-1];
+	    bankIdx[0] = t;
+	    return t;
+	}
 
     if (banks_ptr >= banks_alloc)
     {
+	int * b, * bidx;
 	b = realloc (bankId, (banks_alloc + 4) * sizeof(int));
 	if (!b)
 	    return -1;
-
 	bankId = b;
+
+	bidx = realloc (bankIdx, (banks_alloc + 4) * sizeof(int));
+	if (!bidx)
+	    return -1;
+	bankIdx = bidx;
+
 	banks_alloc += 4;
     }
 
     i = banks_ptr++;
     bankId[i] = bank;
+    bankIdx[i] = i;
     return i;
 }