vm: add factorbug command to throw exception

Also rename "q" to "c" because it "c"ontinues, remove the useless "im" command, and rename the less useful "t" to "trim" so we can use "t" to mean "throw"

basis/debugger/debugger.factor

@@ -134,11 +134,14 @@ HOOK: signal-error. os ( obj -- )
 : fp-trap-error. ( error -- )
     "Floating point trap" print drop ;
 
+: interrupt-error. ( error -- )
+    "Interrupt" print drop ;
+
 PREDICATE: vm-error < array
     {
         { [ dup empty? ] [ drop f ] }
         { [ dup first "kernel-error" = not ] [ drop f ] }
-        [ second 0 17 between? ]
+        [ second 0 18 between? ]
     } cond ;
 
 : vm-errors ( error -- n errors )
@@ -161,6 +164,7 @@ PREDICATE: vm-error < array
         { 15 [ callstack-overflow.     ] }
         { 16 [ memory-error.           ] }
         { 17 [ fp-trap-error.          ] }
+        { 18 [ interrupt-error.        ] }
     } ; inline
 
 M: vm-error summary drop "VM error" ;

vm/debug.cpp

@@ -351,23 +351,22 @@ void factor_vm::factorbug()
 		exit(1);
 	}
 
-	/* open_console(); */
 	fep_p = true;
 
 	std::cout << "Starting low level debugger...\n";
 	std::cout << "  Basic commands:\n";
-	std::cout << "q                -- continue executing Factor - NOT SAFE\n";
-	std::cout << "im               -- save image to fep.image\n";
+	std::cout << "c                -- continue executing Factor - NOT SAFE\n";
+	std::cout << "t                -- throw exception in Factor - NOT SAFE\n";
 	std::cout << "x                -- exit Factor\n";
 	std::cout << "  Advanced commands:\n";
 	std::cout << "d <addr> <count> -- dump memory\n";
 	std::cout << "u <addr>         -- dump object at tagged <addr>\n";
 	std::cout << ". <addr>         -- print object at tagged <addr>\n";
-	std::cout << "t                -- toggle output trimming\n";
 	std::cout << "s r              -- dump data, retain stacks\n";
 	std::cout << ".s .r .c         -- print data, retain, call stacks\n";
 	std::cout << "e                -- dump environment\n";
 	std::cout << "g                -- dump generations\n";
+	std::cout << "trim             -- toggle output trimming\n";
 	std::cout << "data             -- data heap dump\n";
 	std::cout << "words            -- words dump\n";
 	std::cout << "tuples           -- tuples dump\n";
@@ -427,7 +426,7 @@ void factor_vm::factorbug()
 			print_obj(addr);
 			std::cout << std::endl;
 		}
-		else if(strcmp(cmd,"t") == 0)
+		else if(strcmp(cmd,"trim") == 0)
 			full_output = !full_output;
 		else if(strcmp(cmd,"s") == 0)
 			dump_memory(ctx->datastack_seg->start,ctx->datastack);
@@ -446,15 +445,19 @@ void factor_vm::factorbug()
 		}
 		else if(strcmp(cmd,"g") == 0)
 			dump_generations();
-		else if(strcmp(cmd,"q") == 0)
+		else if(strcmp(cmd,"q") == 0 || strcmp(cmd,"c") == 0)
 		{
 			fep_p = false;
 			return;
 		}
+		else if(strcmp(cmd,"t") == 0)
+		{
+			fep_p = false;
+			general_error(ERROR_INTERRUPT,false_object,false_object);
+			assert(false);
+		}
 		else if(strcmp(cmd,"x") == 0)
 			exit(1);
-		else if(strcmp(cmd,"im") == 0)
-			save_image(STRING_LITERAL("fep.image.saving"),STRING_LITERAL("fep.image"));
 		else if(strcmp(cmd,"data") == 0)
 			dump_objects(TYPE_COUNT);
 		else if(strcmp(cmd,"refs") == 0)

vm/errors.cpp

@@ -182,10 +182,10 @@ void factor_vm::handle_safepoint()
 	if (signal_from_leaf)
 		std::cout << "XXX SIGNALED FROM LEAF\n";
 
+	code->unguard_safepoint();
 	if (safepoint_fep) {
 		std::cout << "Interrupted\n";
 		factorbug();
-		code->unguard_safepoint();
 		safepoint_fep = false;
 		return;
 	}

vm/errors.hpp

@@ -22,6 +22,7 @@ enum vm_error_type
 	ERROR_CALLSTACK_OVERFLOW,
 	ERROR_MEMORY,
 	ERROR_FP_TRAP,
+	ERROR_INTERRUPT,
 };
 
 void fatal_error(const char *msg, cell tagged);