+struct inferior_list_entry;
+struct thread_info;
+
+/* The register exists, it has a value, but we don't know what it is.
+ Used when inspecting traceframes. */
+#define REG_UNAVAILABLE 0
+
+/* We know the register's value (and we have it cached). */
+#define REG_VALID 1
+
+/* The data for the register cache. Note that we have one per
+ inferior; this is primarily for simplicity, as the performance
+ benefit is minimal. */
+
+struct regcache
+{
+ /* Whether the REGISTERS buffer's contents are valid. If false, we
+ haven't fetched the registers from the target yet. Not that this
+ register cache is _not_ pass-through, unlike GDB's. Note that
+ "valid" here is unrelated to whether the registers are available
+ in a traceframe. For that, check REGISTER_STATUS below. */
+ int registers_valid;
+ int registers_owned;
+ unsigned char *registers;
+#ifndef IN_PROCESS_AGENT
+ /* One of REG_UNAVAILBLE or REG_VALID. */
+ unsigned char *register_status;
+#endif
+};
+
+struct regcache *init_register_cache (struct regcache *regcache,
+ unsigned char *regbuf);
+
+void regcache_cpy (struct regcache *dst, struct regcache *src);
+