[Qemu-devel] [RFC PATCH 1/3] tb-annotation: Added annotation XML file parser

[Peer Adelt <peer.adelt@c-lab.de>]

The XML file contains a control flow graph, where each edge
is annotated with a context-dependent value. The parser reads
this information into a data structure within CPUState.

Signed-off-by: Peer Adelt <peer.adelt@c-lab.de>
---
 include/qom/cpu.h                            |   9 ++
 include/tb-annotation/tb-annotation-parser.h |  29 +++++
 include/tb-annotation/tb-annotation.h        |  64 ++++++++++
 tb-annotation/tb-annotation-parser.c         | 174 +++++++++++++++++++++++++++
 4 files changed, 276 insertions(+)
 create mode 100644 include/tb-annotation/tb-annotation-parser.h
 create mode 100644 include/tb-annotation/tb-annotation.h
 create mode 100644 tb-annotation/tb-annotation-parser.c

diff --git a/include/qom/cpu.h b/include/qom/cpu.h
index 51a1323..afc532b 100644
--- a/include/qom/cpu.h
+++ b/include/qom/cpu.h
@@ -30,6 +30,10 @@
 #include "qemu/thread.h"
 #include "qemu/typedefs.h"
 
+#ifdef CONFIG_TB_ANNOTATION
+#include "tb-annotation/tb-annotation.h"
+#endif
+
 typedef int (*WriteCoreDumpFunction)(const void *buf, size_t size,
                                      void *opaque);
 
@@ -329,6 +333,11 @@ struct CPUState {
      */
     bool throttle_thread_scheduled;
 
+#ifdef CONFIG_TB_ANNOTATION
+    /* Used to annotate cpu state during tb execution */
+    TbAnnotation *tb_annotation;
+#endif
+
     /* Note that this is accessed at the start of every TB via a negative
        offset from AREG0.  Leave this field at the end so as to make the
        (absolute value) offset as small as possible.  This reduces code
diff --git a/include/tb-annotation/tb-annotation-parser.h b/include/tb-annotation/tb-annotation-parser.h
new file mode 100644
index 0000000..aacab8e
--- /dev/null
+++ b/include/tb-annotation/tb-annotation-parser.h
@@ -0,0 +1,29 @@
+/*
+ *  Copyright (c) 2015-2016 Bastian Koppelmann
+ *                          Peer Adelt
+ *                          C-Lab/Paderborn University
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef INCLUDE_TB_ANNOTATION_PARSER_H_
+#define INCLUDE_TB_ANNOTATION_PARSER_H_
+
+#include "tb-annotation/tb-annotation.h"
+
+void tb_annotation_xml_init(const char *filename);
+void tb_annotation_xml_close(void);
+TbAnnotation *tb_annotation_parse(const char *filename);
+
+#endif /* INCLUDE_TB_ANNOTATION_PARSER_H_ */
diff --git a/include/tb-annotation/tb-annotation.h b/include/tb-annotation/tb-annotation.h
new file mode 100644
index 0000000..e1093b2
--- /dev/null
+++ b/include/tb-annotation/tb-annotation.h
@@ -0,0 +1,64 @@
+/*
+ *  Copyright (c) 2015-2016 Bastian Koppelmann
+ *                          Peer Adelt
+ *                          C-Lab/Paderborn University
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef INCLUDE_TB_ANNOTATION_H_
+#define INCLUDE_TB_ANNOTATION_H_
+
+#include <glib.h>
+
+typedef struct tb_leaving_edge_tuple TbAnnotationLeavingEdgeTuple;
+typedef struct tb_annotation_block TbAnnotationBlock;
+typedef struct tb_annotation_edge TbAnnotationEdge;
+typedef struct tb_annotation TbAnnotation;
+
+struct tb_leaving_edge_tuple {
+    TbAnnotationEdge *out1;
+    TbAnnotationEdge *out2;
+};
+
+struct tb_annotation_block {
+    uint8_t is_end_block;
+    const char *id;
+    unsigned int address;
+    /* This hashtable points to all pairs of leaving edges
+     * from all source contexts.
+     * Note: string -> tb_leaving_edge_tuple
+     */
+    GHashTable *out_edges_hash_table;
+};
+
+struct tb_annotation_edge {
+    TbAnnotationBlock *source;
+    TbAnnotationBlock *target;
+    const char *source_context;
+    const char *target_context;
+    unsigned int value;
+};
+
+struct tb_annotation {
+
+    TbAnnotationBlock *last_block;
+    const char *last_ctx;
+    /* Hashes from PC to TbAnnotationBlock */
+    GHashTable *tb_annotation_blocks;
+    unsigned int value_sum;
+
+};
+
+#endif /* INCLUDE_TB_ANNOTATION_H_ */
diff --git a/tb-annotation/tb-annotation-parser.c b/tb-annotation/tb-annotation-parser.c
new file mode 100644
index 0000000..b3cb2e7
--- /dev/null
+++ b/tb-annotation/tb-annotation-parser.c
@@ -0,0 +1,174 @@
+/*
+ *  Copyright (c) 2015-2016 Bastian Koppelmann
+ *                          Peer Adelt
+ *                          C-Lab/Paderborn University
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <assert.h>
+#include <libxml/parser.h>
+#include <libxml/xpath.h>
+#include <libxml/xpathInternals.h>
+#include <libxml/tree.h>
+
+#include "tb-annotation/tb-annotation.h"
+#include "tb-annotation/tb-annotation-parser.h"
+
+xmlDocPtr tb_annotation_doc;
+xmlXPathContextPtr tb_annotation_xpathctx;
+xmlXPathObjectPtr tb_annotation_xpath;
+
+void tb_annotation_xml_init(const char *filename)
+{
+
+    /* Load XML file */
+    tb_annotation_doc = xmlParseFile(filename);
+    assert(tb_annotation_doc);
+
+    /* Create XPath evaluation context */
+    tb_annotation_xpathctx = xmlXPathNewContext(tb_annotation_doc);
+    assert(tb_annotation_xpathctx);
+}
+
+void tb_annotation_xml_close(void)
+{
+
+    xmlXPathFreeObject(tb_annotation_xpath);
+    xmlXPathFreeContext(tb_annotation_xpathctx);
+    xmlFreeDoc(tb_annotation_doc);
+}
+
+static int32_t tb_annotation_xml_evalxpath(const char *xpath,
+        xmlNodeSetPtr *nodes)
+{
+
+    /* Evaluate the expression */
+    tb_annotation_xpath = xmlXPathEvalExpression(BAD_CAST xpath,
+            tb_annotation_xpathctx);
+    assert(tb_annotation_xpath);
+
+    /* Set the return value */
+    *nodes = tb_annotation_xpath->nodesetval;
+    return tb_annotation_xpath->nodesetval->nodeNr;
+}
+
+TbAnnotation *tb_annotation_parse(const char *filename)
+{
+    int32_t i;
+    xmlNodeSetPtr nodes = NULL;
+    TbAnnotationBlock *cur_block;
+    TbAnnotationLeavingEdgeTuple *cur_leaving_edge_tuple;
+    TbAnnotationEdge *cur_edge;
+    GHashTable *id_to_block = g_hash_table_new(g_str_hash, g_str_equal);
+    TbAnnotation *tba = g_new0(TbAnnotation, 1);
+    tba->tb_annotation_blocks = g_hash_table_new(g_int_hash, g_int_equal);
+
+    /* Open XML file */
+    tb_annotation_xml_init(filename);
+
+    /* Parse Blocks */
+    tb_annotation_xml_evalxpath("/QEMU-annotation/Blocks/Block", &nodes);
+    for (i = 0; i < nodes->nodeNr; i++) {
+
+        /* Read XML description of current block */
+        const char *id = (const char *) xmlGetNoNsProp(
+                nodes->nodeTab[i], BAD_CAST "id");
+        const char *address_str = (const char *) xmlGetNoNsProp(
+                nodes->nodeTab[i], BAD_CAST "address");
+
+        /* Create the block */
+        cur_block = g_new0(TbAnnotationBlock, 1);
+        cur_block->out_edges_hash_table = g_hash_table_new(
+                g_str_hash, g_str_equal);
+        cur_block->id = id;
+        cur_block->address = -1;
+
+        if (g_strcmp0("None", address_str) == 0) {
+
+            cur_block->is_end_block = 1;
+
+        } else {
+
+            cur_block->is_end_block = 0;
+            sscanf(address_str, "%x", &cur_block->address);
+
+            /* Store current block in TbAnnotations PC -> block map */
+            g_hash_table_insert(tba->tb_annotation_blocks, &cur_block->address,
+                    cur_block);
+        }
+
+        /* Store in id -> block map for edge creation */
+        g_hash_table_insert(id_to_block, (gpointer) id, cur_block);
+    }
+
+    /* Parse Edges (also adding out_edges to blocks) */
+    tb_annotation_xml_evalxpath("/QEMU-annotation/Edges/Edge", &nodes);
+    for (i = 0; i < nodes->nodeNr; i++) {
+
+        /* Read XML description of current edge */
+        const char *source_id = (const char *) xmlGetNoNsProp(
+                nodes->nodeTab[i], BAD_CAST "source");
+        const char *source_ctx = (const char *) xmlGetNoNsProp(
+                nodes->nodeTab[i], BAD_CAST "source_context");
+        const char *target_id = (const char *) xmlGetNoNsProp(
+                nodes->nodeTab[i], BAD_CAST "target");
+        const char *target_ctx = (const char *) xmlGetNoNsProp(
+                nodes->nodeTab[i], BAD_CAST "target_context");
+        const char *value_str = (const char *) xmlGetNoNsProp(
+                nodes->nodeTab[i], BAD_CAST "value");
+
+        /* Create the edge */
+        cur_edge = g_new0(TbAnnotationEdge, 1);
+        cur_edge->source = g_hash_table_lookup(id_to_block, source_id);
+        cur_edge->target = g_hash_table_lookup(id_to_block, target_id);
+        cur_edge->source_context = source_ctx;
+        cur_edge->target_context = target_ctx;
+        sscanf(value_str, "%u", &cur_edge->value);
+
+        /* Store this edge in source blocks leaving_edge_tuple */
+        cur_leaving_edge_tuple = g_hash_table_lookup(
+                cur_edge->source->out_edges_hash_table,
+                cur_edge->source_context);
+        if (cur_leaving_edge_tuple == NULL) {
+            cur_leaving_edge_tuple = g_new0(TbAnnotationLeavingEdgeTuple, 1);
+            g_hash_table_insert(cur_edge->source->out_edges_hash_table,
+                    (gpointer) cur_edge->source_context,
+                    cur_leaving_edge_tuple);
+        }
+        /* There must be free space in the leaving_edge_tuple ... */
+        assert(cur_leaving_edge_tuple->out1 == NULL ||
+               cur_leaving_edge_tuple->out2 == NULL);
+        if (cur_leaving_edge_tuple->out1 == NULL) {
+            cur_leaving_edge_tuple->out1 = cur_edge;
+        } else {
+            cur_leaving_edge_tuple->out2 = cur_edge;
+        }
+    }
+
+    /* Parse Startcontext */
+    tb_annotation_xml_evalxpath("/QEMU-annotation/Start-context", &nodes);
+    assert(nodes->nodeNr == 1);
+    tba->last_ctx = (const char *) xmlGetNoNsProp(nodes->nodeTab[0],
+    BAD_CAST "value");
+
+    /* Destroy temporary block id -> block map */
+    g_hash_table_destroy(id_to_block);
+
+    /* Close XML file */
+    tb_annotation_xml_close();
+
+    /* Return TbAnnotation data */
+    return tba;
+}
-- 
2.5.0