vm: don't flush instruction cache twice per code block on a major GC on PowerPC

vm/aging_collector.cpp

@@ -38,7 +38,7 @@ void factor_vm::collect_aging()
 		collector.trace_contexts();
 		collector.trace_code_heap_roots(&code->points_to_aging);
 		collector.cheneys_algorithm();
-		update_dirty_code_blocks(&code->points_to_aging);
+		update_code_heap_for_minor_gc(&code->points_to_aging);
 
 		nursery.here = nursery.start;
 		code->points_to_nursery.clear();

vm/code_block.cpp

@@ -356,6 +356,41 @@ void factor_vm::update_word_references(code_block *compiled)
 	}
 }
 
+/* This runs after a full collection */
+struct literal_and_word_references_updater {
+	factor_vm *myvm;
+
+	explicit literal_and_word_references_updater(factor_vm *myvm_) : myvm(myvm_) {}
+
+	void operator()(relocation_entry rel, cell index, code_block *compiled)
+	{
+		relocation_type type = myvm->relocation_type_of(rel);
+		switch(type)
+		{
+		case RT_IMMEDIATE:
+		case RT_XT:
+		case RT_XT_PIC:
+		case RT_XT_PIC_TAIL:
+			myvm->relocate_code_block_step(rel,index,compiled);
+			break;
+		default:
+			break;
+		}
+	}
+};
+
+void factor_vm::update_code_block_for_full_gc(code_block *compiled)
+{
+	if(code->needs_fixup_p(compiled))
+		relocate_code_block(compiled);
+	else
+	{
+		literal_and_word_references_updater updater(this);
+		iterate_relocations(compiled,updater);
+		flush_icache_for(compiled);
+	}
+}
+
 void factor_vm::check_code_address(cell address)
 {
 #ifdef FACTOR_DEBUG

vm/full_collector.cpp

@@ -97,10 +97,12 @@ void full_collector::cheneys_algorithm()
 	}
 }
 
-struct full_updater {
+/* After growing the heap, we have to perform a full relocation to update
+references to card and deck arrays. */
+struct after_growing_heap_updater {
 	factor_vm *myvm;
 
-	full_updater(factor_vm *myvm_) : myvm(myvm_) {}
+	after_growing_heap_updater(factor_vm *myvm_) : myvm(myvm_) {}
 
 	void operator()(heap_block *block)
 	{
@@ -108,29 +110,29 @@ struct full_updater {
 	}
 };
 
-struct literal_and_word_reference_updater {
+/* After a full GC that did not grow the heap, we have to update references
+to literals and other words. */
+struct after_full_updater {
 	factor_vm *myvm;
 
-	literal_and_word_reference_updater(factor_vm *myvm_) : myvm(myvm_) {}
+	after_full_updater(factor_vm *myvm_) : myvm(myvm_) {}
 
 	void operator()(heap_block *block)
 	{
-		code_block *compiled = (code_block *)block;
+		myvm->update_code_block_for_full_gc((code_block *)block);
-		myvm->update_literal_references(compiled);
-		myvm->update_word_references(compiled);
 	}
 };
 
-void factor_vm::free_unmarked_code_blocks(bool growing_data_heap)
+void factor_vm::update_code_heap_for_full_gc(bool growing_data_heap)
 {
 	if(growing_data_heap)
 	{
-		full_updater updater(this);
+		after_growing_heap_updater updater(this);
 		code->free_unmarked(updater);
 	}
 	else
 	{
-		literal_and_word_reference_updater updater(this);
+		after_full_updater updater(this);
 		code->free_unmarked(updater);
 	}
 
@@ -160,7 +162,7 @@ void factor_vm::collect_growing_heap(cell requested_bytes, bool trace_contexts_p
 	data_heap *old = data;
 	set_data_heap(data->grow(requested_bytes));
 	collect_full_impl(trace_contexts_p);
-	free_unmarked_code_blocks(true);
+	update_code_heap_for_full_gc(true);
 	delete old;
 }
 
@@ -169,7 +171,7 @@ void factor_vm::collect_full(bool trace_contexts_p)
 	std::swap(data->tenured,data->tenured_semispace);
 	reset_generation(data->tenured);
 	collect_full_impl(trace_contexts_p);
-	free_unmarked_code_blocks(false);
+	update_code_heap_for_full_gc(false);
 }
 
 }

vm/gc.cpp

@@ -7,7 +7,7 @@ gc_state::gc_state(gc_op op_) : op(op_), start_time(current_micros()) {}
 
 gc_state::~gc_state() {}
 
-void factor_vm::update_dirty_code_blocks(std::set<code_block *> *remembered_set)
+void factor_vm::update_code_heap_for_minor_gc(std::set<code_block *> *remembered_set)
 {
 	/* The youngest generation that any code block can now reference */
 	std::set<code_block *>::const_iterator iter = remembered_set->begin();

vm/nursery_collector.cpp

@@ -24,7 +24,7 @@ void factor_vm::collect_nursery()
 		simple_unmarker(card_mark_mask));
 	collector.trace_code_heap_roots(&code->points_to_nursery);
 	collector.cheneys_algorithm();
-	update_dirty_code_blocks(&code->points_to_nursery);
+	update_code_heap_for_minor_gc(&code->points_to_nursery);
 
 	nursery.here = nursery.start;
 	code->points_to_nursery.clear();

vm/to_tenured_collector.cpp

@@ -21,7 +21,7 @@ void factor_vm::collect_to_tenured()
 		dummy_unmarker());
 	collector.trace_code_heap_roots(&code->points_to_aging);
 	collector.cheneys_algorithm();
-	update_dirty_code_blocks(&code->points_to_aging);
+	update_code_heap_for_minor_gc(&code->points_to_aging);
 
 	nursery.here = nursery.start;
 	reset_generation(data->aging);

vm/vm.hpp

@@ -234,11 +234,11 @@ struct factor_vm
 	}
 
 	// gc
-	void update_dirty_code_blocks(std::set<code_block *> *remembered_set);
+	void update_code_heap_for_minor_gc(std::set<code_block *> *remembered_set);
 	void collect_nursery();
 	void collect_aging();
 	void collect_to_tenured();
-	void free_unmarked_code_blocks(bool growing_data_heap);
+	void update_code_heap_for_full_gc(bool growing_data_heap);
 	void collect_full_impl(bool trace_contexts_p);
 	void collect_growing_heap(cell requested_bytes, bool trace_contexts_p);
 	void collect_full(bool trace_contexts_p);
@@ -479,6 +479,7 @@ struct factor_vm
 	void update_literal_references(code_block *compiled);
 	void relocate_code_block_step(relocation_entry rel, cell index, code_block *compiled);
 	void update_word_references(code_block *compiled);
+	void update_code_block_for_full_gc(code_block *compiled);
 	void check_code_address(cell address);
 	void relocate_code_block(code_block *compiled);
 	void fixup_labels(array *labels, code_block *compiled);