#include "master.hpp" namespace factor { full_collector::full_collector(factor_vm *parent_) : collector( parent_, parent_->data->tenured, full_policy(parent_)) {} /* After a sweep, invalidate any code heap roots which are not marked, so that if a block makes a tail call to a generic word, and the PIC compiler triggers a GC, and the caller block gets gets GCd as a result, the PIC code won't try to overwrite the call site */ void factor_vm::update_code_roots_for_sweep() { std::vector::const_iterator iter = code_roots.begin(); std::vector::const_iterator end = code_roots.end(); mark_bits *state = &code->allocator->state; for(; iter < end; iter++) { code_root *root = *iter; code_block *block = (code_block *)(root->value & -block_granularity); if(root->valid && !state->marked_p(block)) root->valid = false; } } /* After a compaction, invalidate any code heap roots which are not marked as above, and also slide the valid roots up so that call sites can be updated correctly. */ void factor_vm::update_code_roots_for_compaction() { std::vector::const_iterator iter = code_roots.begin(); std::vector::const_iterator end = code_roots.end(); mark_bits *state = &code->allocator->state; for(; iter < end; iter++) { code_root *root = *iter; code_block *block = (code_block *)(root->value & -block_granularity); /* Offset of return address within 16-byte allocation line */ cell offset = root->value - (cell)block; if(root->valid && state->marked_p((code_block *)root->value)) { block = state->forward_block(block); root->value = (cell)block + offset; } else root->valid = false; } } struct code_block_marker { code_heap *code; full_collector *collector; explicit code_block_marker(code_heap *code_, full_collector *collector_) : code(code_), collector(collector_) {} code_block *operator()(code_block *compiled) { if(!code->marked_p(compiled)) { code->set_marked_p(compiled); collector->trace_literal_references(compiled); } return compiled; } }; void factor_vm::collect_mark_impl(bool trace_contexts_p) { full_collector collector(this); code->clear_mark_bits(); data->tenured->clear_mark_bits(); data->tenured->clear_mark_stack(); code_block_visitor code_marker(this,code_block_marker(code,&collector)); collector.trace_roots(); if(trace_contexts_p) { collector.trace_contexts(); code_marker.visit_context_code_blocks(); code_marker.visit_callback_code_blocks(); } std::vector *mark_stack = &data->tenured->mark_stack; while(!mark_stack->empty()) { object *obj = mark_stack->back(); mark_stack->pop_back(); collector.trace_object(obj); code_marker.visit_object_code_block(obj); } data->reset_generation(data->tenured); data->reset_generation(data->aging); data->reset_generation(&nursery); code->clear_remembered_set(); } void factor_vm::collect_sweep_impl() { current_gc->event->started_data_sweep(); data->tenured->sweep(); update_code_roots_for_sweep(); current_gc->event->ended_data_sweep(); current_gc->event->started_code_sweep(); code->allocator->sweep(); current_gc->event->ended_code_sweep(); } void factor_vm::collect_full(bool trace_contexts_p) { collect_mark_impl(trace_contexts_p); collect_sweep_impl(); if(data->low_memory_p()) collect_compact_impl(trace_contexts_p); else update_code_heap_words_and_literals(); } void factor_vm::collect_compact(bool trace_contexts_p) { collect_mark_impl(trace_contexts_p); collect_compact_impl(trace_contexts_p); } void factor_vm::collect_growing_heap(cell requested_bytes, bool trace_contexts_p) { /* Grow the data heap and copy all live objects to the new heap. */ data_heap *old = data; set_data_heap(data->grow(requested_bytes)); collect_mark_impl(trace_contexts_p); collect_compact_code_impl(trace_contexts_p); delete old; } }