X-Git-Url: http://review.tizen.org/git/?a=blobdiff_plain;f=isl_blk.c;h=29844d5c6d39ffcdc3c9e24e314aec9c8d158a8b;hb=de51a9bc4da5dd3f1f9f57c2362da6f9752c44e0;hp=a7a4496d0bbd62330d626e9349ec1a2734851ed0;hpb=cc726006058136865f8c2f496d3df57b9f937ea5;p=platform%2Fupstream%2Fisl.git

diff --git a/isl_blk.c b/isl_blk.c
index a7a4496..29844d5 100644
--- a/isl_blk.c
+++ b/isl_blk.c
@@ -1,41 +1,68 @@
-#include "isl_blk.h"
+/*
+ * Copyright 2008-2009 Katholieke Universiteit Leuven
+ *
+ * Use of this software is governed by the MIT license
+ *
+ * Written by Sven Verdoolaege, K.U.Leuven, Departement
+ * Computerwetenschappen, Celestijnenlaan 200A, B-3001 Leuven, Belgium
+ */
 
-struct isl_blk isl_blk_alloc(struct isl_ctx *ctx, size_t n)
+#include <isl/blk.h>
+#include <isl_ctx_private.h>
+
+/* The maximal number of cache misses before first element is evicted */
+#define ISL_BLK_MAX_MISS	100
+
+struct isl_blk isl_blk_empty()
 {
 	struct isl_blk block;
+	block.size = 0;
+	block.data = NULL;
+	return block;
+}
 
-	block.data = isl_alloc_array(ctx, isl_int, n);
-	if (!block.data)
-		block.size = -1;
-	else {
-		int i;
-		block.size = n;
-		for (i = 0; i < n; ++i)
-			isl_int_init(block.data[i]);
-	}
+static int isl_blk_is_empty(struct isl_blk block)
+{
+	return block.size == 0 && block.data == NULL;
+}
 
+static struct isl_blk isl_blk_error()
+{
+	struct isl_blk block;
+	block.size = -1;
+	block.data = NULL;
 	return block;
 }
 
-struct isl_blk isl_blk_extend(struct isl_ctx *ctx, struct isl_blk block,
+int isl_blk_is_error(struct isl_blk block)
+{
+	return block.size == -1 && block.data == NULL;
+}
+
+static struct isl_blk extend(struct isl_ctx *ctx, struct isl_blk block,
 				size_t new_n)
 {
+	int i;
+	isl_int *p;
+
 	if (block.size >= new_n)
 		return block;
+
+	p = block.data;
 	block.data = isl_realloc_array(ctx, block.data, isl_int, new_n);
-	if (!block.data)
-		block.size = -1;
-	else {
-		int i;
-		for (i = block.size; i < new_n; ++i)
-			isl_int_init(block.data[i]);
-		block.size = new_n;
+	if (!block.data) {
+		free(p);
+		return isl_blk_error();
 	}
 
+	for (i = block.size; i < new_n; ++i)
+		isl_int_init(block.data[i]);
+	block.size = new_n;
+
 	return block;
 }
 
-void isl_blk_free(struct isl_ctx *ctx, struct isl_blk block)
+static void isl_blk_free_force(struct isl_ctx *ctx, struct isl_blk block)
 {
 	int i;
 
@@ -43,3 +70,65 @@ void isl_blk_free(struct isl_ctx *ctx, struct isl_blk block)
 		isl_int_clear(block.data[i]);
 	free(block.data);
 }
+
+struct isl_blk isl_blk_alloc(struct isl_ctx *ctx, size_t n)
+{
+	int i;
+	struct isl_blk block;
+
+	block = isl_blk_empty();
+	if (n && ctx->n_cached) {
+		int best = 0;
+		for (i = 1; ctx->cache[best].size != n && i < ctx->n_cached; ++i) {
+			if (ctx->cache[best].size < n) {
+				if (ctx->cache[i].size > ctx->cache[best].size)
+					best = i;
+			} else if (ctx->cache[i].size >= n &&
+				   ctx->cache[i].size < ctx->cache[best].size)
+					best = i;
+		}
+		if (ctx->cache[best].size < 2 * n + 100) {
+			block = ctx->cache[best];
+			if (--ctx->n_cached != best)
+				ctx->cache[best] = ctx->cache[ctx->n_cached];
+			if (best == 0)
+				ctx->n_miss = 0;
+		} else if (ctx->n_miss++ >= ISL_BLK_MAX_MISS) {
+			isl_blk_free_force(ctx, ctx->cache[0]);
+			if (--ctx->n_cached != 0)
+				ctx->cache[0] = ctx->cache[ctx->n_cached];
+			ctx->n_miss = 0;
+		}
+	}
+
+	return extend(ctx, block, n);
+}
+
+struct isl_blk isl_blk_extend(struct isl_ctx *ctx, struct isl_blk block,
+				size_t new_n)
+{
+	if (isl_blk_is_empty(block))
+		return isl_blk_alloc(ctx, new_n);
+
+	return extend(ctx, block, new_n);
+}
+
+void isl_blk_free(struct isl_ctx *ctx, struct isl_blk block)
+{
+	if (isl_blk_is_empty(block) || isl_blk_is_error(block))
+		return;
+
+	if (ctx->n_cached < ISL_BLK_CACHE_SIZE)
+		ctx->cache[ctx->n_cached++] = block;
+	else
+		isl_blk_free_force(ctx, block);
+}
+
+void isl_blk_clear_cache(struct isl_ctx *ctx)
+{
+	int i;
+
+	for (i = 0; i < ctx->n_cached; ++i)
+		isl_blk_free_force(ctx, ctx->cache[i]);
+	ctx->n_cached = 0;
+}