Mixed mode exception handling (mono#4777)

* [mixed] Add beginnings of unwinding support for interp->jit transitions by pushing an LMF frame on the stack when exiting interpreted code.

* [runtime] Add a mono_debug_lookup_source_location_by_il () helper function to lookup a source location using an IL offset.

* [mixed] Add support for mixed mode managed stack walks.

* [interp] Generate line number info for interpreted code, using the same MonoDebugMethodJitInfo structure used by the JIT.

* [interp] Pass the clause index to the MINT_ENDFINALLY opcode. Not yet used.

* [interp] Create a MonoJitInfo structure for each interpreted method. Not yet used.

* [interp] Add a mono_interp_set_resume_state () function which can be used to set the frame/ip the interpreter will resume execution from when execution returns to it.

* [mixed] Add support for mixed mode exception handling by extending the normal JIT exception handling code in mini-exceptions.c to handle interpreted frames as well.

* [jit] Add an Unwinder type to reduce the amount of code duplication when unwinding though interpreter frames.

* [interp] Fix the !ENABLE_INTERPRETER build.

* [interp] Disable an assert which is hit even when running without --interpreter.

* Fix a comment.

* [interp] Fix an assertion. Fix/add comments.

mono/metadata/debug-internals.h

@@ -84,4 +84,7 @@ mono_debug_free_method_async_debug_info (MonoDebugMethodAsyncInfo *info);
 gboolean
 mono_debug_image_has_debug_info (MonoImage *image);
 
+MonoDebugSourceLocation *
+mono_debug_lookup_source_location_by_il (MonoMethod *method, guint32 il_offset, MonoDomain *domain);
+
 #endif /* __DEBUG_INTERNALS_H__ */

mono/metadata/mono-debug.c

@@ -793,6 +793,40 @@ mono_debug_lookup_source_location (MonoMethod *method, guint32 address, MonoDoma
 	return location;
 }
 
+/**
+ * mono_debug_lookup_source_location_by_il:
+ *
+ *   Same as mono_debug_lookup_source_location but take an IL_OFFSET argument.
+ */
+MonoDebugSourceLocation *
+mono_debug_lookup_source_location_by_il (MonoMethod *method, guint32 il_offset, MonoDomain *domain)
+{
+	MonoDebugMethodInfo *minfo;
+	MonoDebugSourceLocation *location;
+
+	if (mono_debug_format == MONO_DEBUG_FORMAT_NONE)
+		return NULL;
+
+	mono_debugger_lock ();
+	minfo = mono_debug_lookup_method_internal (method);
+	if (!minfo || !minfo->handle) {
+		mono_debugger_unlock ();
+		return NULL;
+	}
+
+	if (!minfo->handle->ppdb && (!minfo->handle->symfile || !mono_debug_symfile_is_loaded (minfo->handle->symfile))) {
+		mono_debugger_unlock ();
+		return NULL;
+	}
+
+	if (minfo->handle->ppdb)
+		location = mono_ppdb_lookup_location (minfo, il_offset);
+	else
+		location = mono_debug_symfile_lookup_location (minfo, il_offset);
+	mono_debugger_unlock ();
+	return location;
+}
+
 MonoDebugSourceLocation *
 mono_debug_method_lookup_location (MonoDebugMethodInfo *minfo, int il_offset)
 {

mono/metadata/object.c

@@ -7826,7 +7826,7 @@ mono_delegate_ctor_with_method (MonoObject *this_obj, MonoObject *target, gpoint
 		g_assert (method);
 		method = mono_marshal_get_remoting_invoke (method);
 #ifdef ENABLE_INTERPRETER
-		g_error ("need RuntimeMethod in method_ptr when using interpreter");
+		//g_error ("need RuntimeMethod in method_ptr when using interpreter");
 #endif
 		delegate->method_ptr = mono_compile_method_checked (method, error);
 		return_val_if_nok (error, FALSE);

mono/mini/exceptions-amd64.c

@@ -582,20 +582,24 @@ mono_arch_unwind_frame (MonoDomain *domain, MonoJitTlsData *jit_tls,
 		guint64 rip;
 
 		if (((guint64)(*lmf)->previous_lmf) & 2) {
-			/* 
-			 * This LMF entry is created by the soft debug code to mark transitions to
-			 * managed code done during invokes.
-			 */
 			MonoLMFExt *ext = (MonoLMFExt*)(*lmf);
 
-			g_assert (ext->debugger_invoke);
-
-			memcpy (new_ctx, &ext->ctx, sizeof (MonoContext));
+			if (ext->debugger_invoke) {
+				/*
+				 * This LMF entry is created by the soft debug code to mark transitions to
+				 * managed code done during invokes.
+				 */
+				frame->type = FRAME_TYPE_DEBUGGER_INVOKE;
+				memcpy (new_ctx, &ext->ctx, sizeof (MonoContext));
+			} else if (ext->interp_exit) {
+				frame->type = FRAME_TYPE_INTERP_TO_MANAGED;
+				frame->interp_exit_data = ext->interp_exit_data;
+			} else {
+				g_assert_not_reached ();
+			}
 
 			*lmf = (MonoLMF *)(((guint64)(*lmf)->previous_lmf) & ~7);
 
-			frame->type = FRAME_TYPE_DEBUGGER_INVOKE;
-
 			return TRUE;
 		}
 

mono/mini/interp/interp-internals.h

@@ -7,6 +7,7 @@
 #include <mono/metadata/object.h>
 #include <mono/metadata/domain-internals.h>
 #include <mono/metadata/class-internals.h>
+#include <mono/metadata/debug-internals.h>
 #include "config.h"
 
 enum {
@@ -88,6 +89,7 @@ typedef struct _RuntimeMethod
 	gpointer jit_entry;
 	MonoType *rtype;
 	MonoType **param_types;
+	MonoJitInfo *jinfo;
 } RuntimeMethod;
 
 struct _MonoInvocation {
@@ -115,6 +117,13 @@ typedef struct {
 	jmp_buf *current_env;
 	unsigned char search_for_handler;
 	unsigned char managed_code;
+
+	/* Resume state for resuming execution in mixed mode */
+	gboolean       has_resume_state;
+	/* Frame to resume execution at */
+	MonoInvocation *handler_frame;
+	/* IP to resume execution at */
+	gpointer handler_ip;
 } ThreadContext;
 
 extern int mono_interp_traceopt;