Changeset 4c925cd for libcfa/src/exception.c

Timestamp:

Aug 14, 2020, 11:40:04 AM (3 years ago)

Author:

Thierry Delisle <tdelisle@…>

Branches:

ADT, arm-eh, enum, forall-pointer-decay, jacob/cs343-translation, master, new-ast, new-ast-unique-expr, pthread-emulation, qualifiedEnum

Children:

5715d43, fa5e011

Parents:

309d814 (diff), badd22f (diff)
Note: this is a merge changeset, the changes displayed below correspond to the merge itself.
Use the (diff) links above to see all the changes relative to each parent.

Message:

Merge branch 'master' of plg.uwaterloo.ca:software/cfa/cfa-cc

File:

• libcfa/src/exception.c (modified) (13 diffs)

libcfa/src/exception.c

@@ -10 +10 @@
 // Created On       : Mon Jun 26 15:13:00 2017
 // Last Modified By : Andrew Beach
-// Last Modified On : Thr May 21 12:18:00 2020
-// Update Count     : 20
+// Last Modified On : Wed Aug 12 13:55:00 2020
+// Update Count     : 21
 //
 
@@ -28 +28 @@
 #include <unwind.h>
 #include <bits/debug.hfa>
+#include "concurrency/invoke.h"
 #include "stdhdr/assert.h"
 
@@ -59 +60 @@
 
 // Temperary global exception context. Does not work with concurency.
-struct exception_context_t {
-        struct __cfaehm_try_resume_node * top_resume;
-
-        exception_t * current_exception;
-        int current_handler_index;
-} static shared_stack = {NULL, NULL, 0};
+static struct exception_context_t shared_stack = {NULL, NULL};
 
 // Get the current exception context.
@@ -122 +118 @@
 
 // MEMORY MANAGEMENT =========================================================
+
+struct __cfaehm_node {
+        struct _Unwind_Exception unwind_exception;
+        struct __cfaehm_node * next;
+        int handler_index;
+};
+
+#define NODE_TO_EXCEPT(node) ((exception_t *)(1 + (node)))
+#define EXCEPT_TO_NODE(except) ((struct __cfaehm_node *)(except) - 1)
+#define UNWIND_TO_NODE(unwind) ((struct __cfaehm_node *)(unwind))
+#define NULL_MAP(map, ptr) ((ptr) ? (map(ptr)) : NULL)
 
 // How to clean up an exception in various situations.
@@ -137 +144 @@
 }
 
-// We need a piece of storage to raise the exception, for now its a single
-// piece.
-static struct _Unwind_Exception this_exception_storage;
-
-struct __cfaehm_node {
-        struct __cfaehm_node * next;
-};
-
-#define NODE_TO_EXCEPT(node) ((exception_t *)(1 + (node)))
-#define EXCEPT_TO_NODE(except) ((struct __cfaehm_node *)(except) - 1)
-
 // Creates a copy of the indicated exception and sets current_exception to it.
 static void __cfaehm_allocate_exception( exception_t * except ) {
@@ -161 +157 @@
         }
 
+        // Initialize the node:
+        exception_t * except_store = NODE_TO_EXCEPT(store);
+        store->unwind_exception.exception_class = __cfaehm_exception_class;
+        store->unwind_exception.exception_cleanup = __cfaehm_exception_cleanup;
+        store->handler_index = 0;
+        except->virtual_table->copy( except_store, except );
+
         // Add the node to the list:
-        store->next = EXCEPT_TO_NODE(context->current_exception);
-        context->current_exception = NODE_TO_EXCEPT(store);
-
-        // Copy the exception to storage.
-        except->virtual_table->copy( context->current_exception, except );
-
-        // Set up the exception storage.
-        this_exception_storage.exception_class = __cfaehm_exception_class;
-        this_exception_storage.exception_cleanup = __cfaehm_exception_cleanup;
+        store->next = NULL_MAP(EXCEPT_TO_NODE, context->current_exception);
+        context->current_exception = except_store;
 }
 
@@ -185 +181 @@
         if ( context->current_exception == except ) {
                 node = to_free->next;
-                context->current_exception = (node) ? NODE_TO_EXCEPT(node) : 0;
+                context->current_exception = NULL_MAP(NODE_TO_EXCEPT, node);
         } else {
                 node = EXCEPT_TO_NODE(context->current_exception);
@@ -213 +209 @@
         // Verify actions follow the rules we expect.
         verify((actions & _UA_CLEANUP_PHASE) && (actions & _UA_FORCE_UNWIND));
-        verify(!(actions & (_UA_SEARCH_PHASE | _UA_HANDER_FRAME)));
+        verify(!(actions & (_UA_SEARCH_PHASE | _UA_HANDLER_FRAME)));
 
         if ( actions & _UA_END_OF_STACK ) {
@@ -222 +218 @@
 }
 
+static struct _Unwind_Exception cancel_exception_storage;
+
 // Cancel the current stack, prefroming approprate clean-up and messaging.
 void __cfaehm_cancel_stack( exception_t * exception ) {
         // TODO: Detect current stack and pick a particular stop-function.
         _Unwind_Reason_Code ret;
-        ret = _Unwind_ForcedUnwind( &this_exception_storage, _Stop_Fn, (void*)0x22 );
+        ret = _Unwind_ForcedUnwind( &cancel_exception_storage, _Stop_Fn, (void*)0x22 );
         printf("UNWIND ERROR %d after force unwind\n", ret);
         abort();
@@ -247 +245 @@
 static void __cfaehm_begin_unwind(void(*defaultHandler)(exception_t *)) {
         struct exception_context_t * context = this_exception_context();
-        struct _Unwind_Exception * storage = &this_exception_storage;
         if ( NULL == context->current_exception ) {
                 printf("UNWIND ERROR missing exception in begin unwind\n");
                 abort();
         }
+        struct _Unwind_Exception * storage =
+                &EXCEPT_TO_NODE(context->current_exception)->unwind_exception;
 
         // Call stdlibc to raise the exception
@@ -419 +418 @@
                                 _Unwind_Reason_Code ret = (0 == index)
                                         ? _URC_CONTINUE_UNWIND : _URC_HANDLER_FOUND;
-                                context->current_handler_index = index;
+                                UNWIND_TO_NODE(unwind_exception)->handler_index = index;
 
                                 // Based on the return value, check if we matched the exception
@@ -425 +424 @@
                                         __cfadbg_print_safe(exception, " handler found\n");
                                 } else {
+                                        // TODO: Continue the search if there is more in the table.
                                         __cfadbg_print_safe(exception, " no handler\n");
                                 }
@@ -516 +516 @@
         // Exception handler
         // Note: Saving the exception context on the stack breaks termination exceptions.
-        catch_block( this_exception_context()->current_handler_index,
+        catch_block( EXCEPT_TO_NODE( this_exception_context()->current_exception )->handler_index,
                      this_exception_context()->current_exception );
 }