trace: [all] Add "guest_mem_before" event

The event is described in "trace-events". Note that the "MO_AMASK" flag
is not traced, since it does not seem to affect the visible semantics of
instructions.

[s/inline inline/inline/ to fix clang build.
--Stefan]

Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 146549350711.18437.726780393247474362.stgit@fimbulvetr.bsc.es
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

2 files changed, 80 insertions, 0 deletions

diff --git a/trace/mem-internal.h b/trace/mem-internal.h
new file mode 100644
index 0000000000..a75e0ff732
--- /dev/null
+++ b/trace/mem-internal.h
@@ -0,0 +1,46 @@
+/*
+ * Helper functions for guest memory tracing
+ *
+ * Copyright (C) 2016 Lluís Vilanova <vilanova@ac.upc.edu>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#ifndef TRACE__MEM_INTERNAL_H
+#define TRACE__MEM_INTERNAL_H
+
+static inline uint8_t trace_mem_get_info(TCGMemOp op, bool store)
+{
+    uint8_t res = op;
+    bool be = (op & MO_BSWAP) == MO_BE;
+
+    /* remove untraced fields */
+    res &= (1ULL << 4) - 1;
+    /* make endianness absolute */
+    res &= ~MO_BSWAP;
+    if (be) {
+        res |= 1ULL << 3;
+    }
+    /* add fields */
+    if (store) {
+        res |= 1ULL << 4;
+    }
+
+    return res;
+}
+
+static inline uint8_t trace_mem_build_info(
+    TCGMemOp size, bool sign_extend, TCGMemOp endianness, bool store)
+{
+    uint8_t res = 0;
+    res |= size;
+    res |= (sign_extend << 2);
+    if (endianness == MO_BE) {
+        res |= (1ULL << 3);
+    }
+    res |= (store << 4);
+    return res;
+}
+
+#endif  /* TRACE__MEM_INTERNAL_H */
diff --git a/trace/mem.h b/trace/mem.h
new file mode 100644
index 0000000000..c76a572689
--- /dev/null
+++ b/trace/mem.h
@@ -0,0 +1,34 @@
+/*
+ * Helper functions for guest memory tracing
+ *
+ * Copyright (C) 2016 Lluís Vilanova <vilanova@ac.upc.edu>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#ifndef TRACE__MEM_H
+#define TRACE__MEM_H
+
+#include "tcg/tcg.h"
+
+
+/**
+ * trace_mem_get_info:
+ *
+ * Return a value for the 'info' argument in guest memory access traces.
+ */
+static uint8_t trace_mem_get_info(TCGMemOp op, bool store);
+
+/**
+ * trace_mem_build_info:
+ *
+ * Return a value for the 'info' argument in guest memory access traces.
+ */
+static uint8_t trace_mem_build_info(TCGMemOp size, bool sign_extend,
+                                    TCGMemOp endianness, bool store);
+
+
+#include "trace/mem-internal.h"
+
+#endif  /* TRACE__MEM_H */