86Box/src/codegen_new/codegen_block.c

#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <86box/86box.h>
#include "cpu.h"
#include <86box/mem.h>

#include "x86.h"
#include "x86_flags.h"
#include "x86_ops.h"
#include "x87.h"

#include "386_common.h"

#include "codegen.h"
#include "codegen_accumulate.h"
#include "codegen_allocator.h"
#include "codegen_backend.h"
#include "codegen_ir.h"
#include "codegen_reg.h"

uint8_t *block_write_data = NULL;

int      codegen_flat_ds, codegen_flat_ss;
int      mmx_ebx_ecx_loaded;
int      codegen_flags_changed = 0;
int      codegen_fpu_entered   = 0;
int      codegen_mmx_entered   = 0;
int      codegen_fpu_loaded_iq[8];
x86seg  *op_ea_seg;
int      op_ssegs;
uint32_t op_old_pc;

uint32_t recomp_page = -1;

int        block_current = 0;
static int block_num;
int        block_pos;

uint32_t codegen_endpc;

int        codegen_block_cycles;
static int codegen_block_ins;
static int codegen_block_full_ins;

static uint32_t last_op32;
static x86seg  *last_ea_seg;
static int      last_ssegs;

#ifdef DEBUG_EXTRA
uint32_t instr_counts[256 * 256];
#endif

static uint16_t block_free_list;
static void     delete_block(codeblock_t *block);
static void     delete_dirty_block(codeblock_t *block);

/*Temporary list of code blocks that have recently been evicted. This allows for
  some historical state to be kept when a block is the target of self-modifying
  code.

  The size of this list is limited to DIRTY_LIST_MAX_SIZE blocks. When this is
  exceeded the oldest entry will be moved to the free list.*/
static uint16_t block_dirty_list_head, block_dirty_list_tail;
static int      dirty_list_size = 0;
#define DIRTY_LIST_MAX_SIZE 64

static void
block_free_list_add(codeblock_t *block)
{
#ifndef RELEASE_BUILD
    if (block->flags & CODEBLOCK_IN_DIRTY_LIST)
        fatal("block_free_list_add: block=%p in dirty list\n", block);
#endif
    if (block_free_list)
        block->next = block_free_list;
    else
        block->next = 0;
    block_free_list = get_block_nr(block);
    block->flags    = CODEBLOCK_IN_FREE_LIST;
}

static void
block_dirty_list_add(codeblock_t *block)
{
#ifndef RELEASE_BUILD
    if (block->flags & CODEBLOCK_IN_DIRTY_LIST)
        fatal("block_dirty_list_add: block=%p already in dirty list\n", block);
#endif
    if (block_dirty_list_head != BLOCK_INVALID) {
        codeblock_t *old_head = &codeblock[block_dirty_list_head];

        block->next           = block_dirty_list_head;
        block->prev           = BLOCK_INVALID;
        block_dirty_list_head = old_head->prev = get_block_nr(block);
    } else {
        /*List empty*/
        block->prev = block->next = BLOCK_INVALID;
        block_dirty_list_head = block_dirty_list_tail = get_block_nr(block);
    }
    block->flags |= CODEBLOCK_IN_DIRTY_LIST;
    dirty_list_size++;
    if (dirty_list_size > DIRTY_LIST_MAX_SIZE) {
        /*Evict oldest block to the free list*/
        codeblock_t *evict_block = &codeblock[block_dirty_list_tail];

#ifndef RELEASE_BUILD
        if (!(evict_block->flags & CODEBLOCK_IN_DIRTY_LIST))
            fatal("block_dirty_list_add: evict_block=%p %x %x not in dirty list\n", evict_block, evict_block->phys, evict_block->flags);
        if (!block_dirty_list_tail)
            fatal("block_dirty_list_add - !block_dirty_list_tail\n");
        if (evict_block->prev == BLOCK_INVALID)
            fatal("block_dirty_list_add - evict_block->prev == BLOCK_INVALID\n");
#endif

        block_dirty_list_tail             = evict_block->prev;
        codeblock[evict_block->prev].next = BLOCK_INVALID;

        dirty_list_size--;
        evict_block->flags &= ~CODEBLOCK_IN_DIRTY_LIST;
        delete_dirty_block(evict_block);
    }
}

static void
block_dirty_list_remove(codeblock_t *block)
{
    codeblock_t *prev_block = &codeblock[block->prev];
    codeblock_t *next_block = &codeblock[block->next];

#ifndef RELEASE_BUILD
    if (!(block->flags & CODEBLOCK_IN_DIRTY_LIST))
        fatal("block_dirty_list_remove: block=%p not in dirty list\n", block);
#endif

    /*Is block head of list*/
    if (block->prev == BLOCK_INVALID)
        block_dirty_list_head = block->next;
    else
        prev_block->next = block->next;

    /*Is block tail of list?*/
    if (block->next == BLOCK_INVALID)
        block_dirty_list_tail = block->prev;
    else
        next_block->prev = block->prev;

    dirty_list_size--;
#ifndef RELEASE_BUILD
    if (dirty_list_size < 0)
        fatal("remove - dirty_list_size < 0!\n");
#endif
    block->flags &= ~CODEBLOCK_IN_DIRTY_LIST;
}

int
codegen_purge_purgable_list(void)
{
    if (purgable_page_list_head) {
        page_t *page = &pages[purgable_page_list_head];

        if (page->code_present_mask & page->dirty_mask) {
            codegen_check_flush(page, page->dirty_mask, purgable_page_list_head << 12);

            if (block_free_list)
                return 1;
        }
    }
    return 0;
}

static codeblock_t *
block_free_list_get(void)
{
    codeblock_t *block = NULL;

    while (!block_free_list) {
        /*Free list is empty, check the dirty list*/
        if (block_dirty_list_tail) {
#ifndef RELEASE_BUILD
            if (dirty_list_size <= 0)
                fatal("get - dirty_list_size <= 0!\n");
#endif
            /*Reuse oldest block*/
            block = &codeblock[block_dirty_list_tail];

            block_dirty_list_tail = block->prev;
            if (block->prev == BLOCK_INVALID)
                block_dirty_list_head = BLOCK_INVALID;
            else
                codeblock[block->prev].next = BLOCK_INVALID;
            dirty_list_size--;
            block->flags &= ~CODEBLOCK_IN_DIRTY_LIST;
            delete_dirty_block(block);
            block_free_list = get_block_nr(block);
            break;
        }
        /*Free list is empty - free up a block*/
        if (!codegen_purge_purgable_list())
            codegen_delete_random_block(0);
    }

    block           = &codeblock[block_free_list];
    block_free_list = block->next;
    block->flags &= ~CODEBLOCK_IN_FREE_LIST;
    block->next = 0;
    return block;
}

void
codegen_init(void)
{
    int c;

    codegen_allocator_init();

    codegen_backend_init();
    block_free_list = 0;
    for (c = 0; c < BLOCK_SIZE; c++)
        block_free_list_add(&codeblock[c]);
    block_dirty_list_head = block_dirty_list_tail = 0;
    dirty_list_size                               = 0;
#ifdef DEBUG_EXTRA
    memset(instr_counts, 0, sizeof(instr_counts));
#endif
}

void
codegen_close(void)
{
#ifdef DEBUG_EXTRA
    pclog("Instruction counts :\n");
    while (1) {
        int      c;
        uint32_t highest_num = 0, highest_idx = 0;

        for (c = 0; c < 256 * 256; c++) {
            if (instr_counts[c] > highest_num) {
                highest_num = instr_counts[c];
                highest_idx = c;
            }
        }
        if (!highest_num)
            break;

        instr_counts[highest_idx] = 0;
        if (highest_idx > 256)
            pclog(" %02x %02x = %u\n", highest_idx >> 8, highest_idx & 0xff, highest_num);
        else
            pclog("    %02x = %u\n", highest_idx & 0xff, highest_num);
    }
#endif
}

void
codegen_reset(void)
{
    int c;

    for (c = 1; c < BLOCK_SIZE; c++) {
        codeblock_t *block = &codeblock[c];

        if (block->pc != BLOCK_PC_INVALID) {
            block->phys   = 0;
            block->phys_2 = 0;
            delete_block(block);
        }
    }

    memset(codeblock, 0, BLOCK_SIZE * sizeof(codeblock_t));
    memset(codeblock_hash, 0, HASH_SIZE * sizeof(uint16_t));
    mem_reset_page_blocks();

    block_free_list = 0;
    for (c = 0; c < BLOCK_SIZE; c++) {
        codeblock[c].pc = BLOCK_PC_INVALID;
        block_free_list_add(&codeblock[c]);
    }
}

void
dump_block(void)
{
    /*        codeblock_t *block = pages[0x119000 >> 12].block;

            pclog("dump_block:\n");
            while (block)
            {
                    uint32_t start_pc = (block->pc & 0xffc) | (block->phys & ~0xfff);
                    uint32_t end_pc = (block->endpc & 0xffc) | (block->phys & ~0xfff);
                    pclog(" %p : %08x-%08x  %08x-%08x %p %p\n", (void *)block, start_pc, end_pc,  block->pc, block->endpc, (void *)block->prev, (void *)block->next);
                    if (!block->pc)
                            fatal("Dead PC=0\n");

                    block = block->next;
            }
            pclog("dump_block done\n");*/
}

static void
add_to_block_list(codeblock_t *block)
{
    uint16_t block_prev_nr = pages[block->phys >> 12].block;
    uint16_t block_nr      = get_block_nr(block);

#ifndef RELEASE_BUILD
    if (!block->page_mask)
        fatal("add_to_block_list - mask = 0 %llx %llx\n", block->page_mask, block->page_mask2);
#endif

    if (block_prev_nr) {
        block->next                    = block_prev_nr;
        codeblock[block_prev_nr].prev  = block_nr;
        pages[block->phys >> 12].block = block_nr;
    } else {
        block->next                    = BLOCK_INVALID;
        pages[block->phys >> 12].block = block_nr;
    }

    if (block->next) {
#ifndef RELEASE_BUILD
        if (codeblock[block->next].pc == BLOCK_PC_INVALID)
            fatal("block->next->pc=BLOCK_PC_INVALID %p %p %x %x\n", (void *) &codeblock[block->next], (void *) codeblock, block_current, block_pos);
#endif
    }

    if (block->page_mask2) {
        block->flags |= CODEBLOCK_HAS_PAGE2;

        block_prev_nr = pages[block->phys_2 >> 12].block_2;

        if (block_prev_nr) {
            block->next_2                      = block_prev_nr;
            codeblock[block_prev_nr].prev_2    = block_nr;
            pages[block->phys_2 >> 12].block_2 = block_nr;
        } else {
            block->next_2                      = BLOCK_INVALID;
            pages[block->phys_2 >> 12].block_2 = block_nr;
        }
    }
}

static void
remove_from_block_list(codeblock_t *block, uint32_t pc)
{
    if (!block->page_mask)
        return;
#ifndef RELEASE_BUILD
    if (block->flags & CODEBLOCK_IN_DIRTY_LIST)
        fatal("remove_from_block_list: in dirty list\n");
#endif
    if (block->prev) {
        codeblock[block->prev].next = block->next;
        if (block->next)
            codeblock[block->next].prev = block->prev;
    } else {
        pages[block->phys >> 12].block = block->next;
        if (block->next)
            codeblock[block->next].prev = BLOCK_INVALID;
        else
            mem_flush_write_page(block->phys, 0);
    }

    if (!(block->flags & CODEBLOCK_HAS_PAGE2)) {
#ifndef RELEASE_BUILD
        if (block->prev_2 || block->next_2)
            fatal("Invalid block_2 %x %p %08x\n", block->flags, block, block->phys);
#endif
        return;
    }
    block->flags &= ~CODEBLOCK_HAS_PAGE2;

    if (block->prev_2) {
        codeblock[block->prev_2].next_2 = block->next_2;
        if (block->next_2)
            codeblock[block->next_2].prev_2 = block->prev_2;
    } else {
        pages[block->phys_2 >> 12].block_2 = block->next_2;
        if (block->next_2)
            codeblock[block->next_2].prev_2 = BLOCK_INVALID;
        else
            mem_flush_write_page(block->phys_2, 0);
    }
}

static void
invalidate_block(codeblock_t *block)
{
    uint32_t old_pc = block->pc;

#ifndef RELEASE_BUILD
    if (block->flags & CODEBLOCK_IN_DIRTY_LIST)
        fatal("invalidate_block: already in dirty list\n");
    if (block->pc == BLOCK_PC_INVALID)
        fatal("Invalidating deleted block\n");
#endif
    remove_from_block_list(block, old_pc);
    block_dirty_list_add(block);
    if (block->head_mem_block)
        codegen_allocator_free(block->head_mem_block);
    block->head_mem_block = NULL;
}

static void
delete_block(codeblock_t *block)
{
    uint32_t old_pc = block->pc;

    if (block == &codeblock[codeblock_hash[HASH(block->phys)]])
        codeblock_hash[HASH(block->phys)] = BLOCK_INVALID;

#ifndef RELEASE_BUILD
    if (block->pc == BLOCK_PC_INVALID)
        fatal("Deleting deleted block\n");
#endif
    block->pc = BLOCK_PC_INVALID;

    codeblock_tree_delete(block);
    if (block->flags & CODEBLOCK_IN_DIRTY_LIST)
        block_dirty_list_remove(block);
    else
        remove_from_block_list(block, old_pc);
    if (block->head_mem_block)
        codegen_allocator_free(block->head_mem_block);
    block->head_mem_block = NULL;
    block_free_list_add(block);
}

static void
delete_dirty_block(codeblock_t *block)
{
    if (block == &codeblock[codeblock_hash[HASH(block->phys)]])
        codeblock_hash[HASH(block->phys)] = BLOCK_INVALID;

#ifndef RELEASE_BUILD
    if (block->pc == BLOCK_PC_INVALID)
        fatal("Deleting deleted block\n");
#endif
    block->pc = BLOCK_PC_INVALID;

    codeblock_tree_delete(block);
    block_free_list_add(block);
}

void
codegen_delete_block(codeblock_t *block)
{
    if (block->pc != BLOCK_PC_INVALID)
        delete_block(block);
}

void
codegen_delete_random_block(int required_mem_block)
{
    int block_nr = rand() & BLOCK_MASK;

    while (1) {
        if (block_nr && block_nr != block_current) {
            codeblock_t *block = &codeblock[block_nr];

            if (block->pc != BLOCK_PC_INVALID && (!required_mem_block || block->head_mem_block)) {
                delete_block(block);
                return;
            }
        }
        block_nr = (block_nr + 1) & BLOCK_MASK;
    }
}

void
codegen_check_flush(page_t *page, uint64_t mask, uint32_t phys_addr)
{
    uint16_t block_nr               = page->block;
    int      remove_from_evict_list = 0;
    int      c;

    while (block_nr) {
        codeblock_t *block      = &codeblock[block_nr];
        uint16_t     next_block = block->next;

        if (*block->dirty_mask & block->page_mask) {
            invalidate_block(block);
        }
#ifndef RELEASE_BUILD
        if (block_nr == next_block)
            fatal("Broken 1\n");
#endif
        block_nr = next_block;
    }

    block_nr = page->block_2;

    while (block_nr) {
        codeblock_t *block      = &codeblock[block_nr];
        uint16_t     next_block = block->next_2;

        if (*block->dirty_mask2 & block->page_mask2) {
            invalidate_block(block);
        }
#ifndef RELEASE_BUILD
        if (block_nr == next_block)
            fatal("Broken 2\n");
#endif
        block_nr = next_block;
    }

    if (page->code_present_mask & page->dirty_mask)
        remove_from_evict_list = 1;
    page->code_present_mask &= ~page->dirty_mask;
    page->dirty_mask = 0;

    for (c = 0; c < 64; c++) {
        if (page->byte_code_present_mask[c] & page->byte_dirty_mask[c])
            remove_from_evict_list = 0;
        page->byte_code_present_mask[c] &= ~page->byte_dirty_mask[c];
        page->byte_dirty_mask[c] = 0;
    }
    if (remove_from_evict_list)
        page_remove_from_evict_list(page);
}

void
codegen_block_init(uint32_t phys_addr)
{
    codeblock_t *block;
    page_t      *page = &pages[phys_addr >> 12];

    if (!page->block)
        mem_flush_write_page(phys_addr, cs + cpu_state.pc);
    block = block_free_list_get();
#ifndef RELEASE_BUILD
    if (!block)
        fatal("codegen_block_init: block_free_list_get() returned NULL\n");
#endif
    block_current = get_block_nr(block);

    block_num                 = HASH(phys_addr);
    codeblock_hash[block_num] = block_current;

    block->ins         = 0;
    block->pc          = cs + cpu_state.pc;
    block->_cs         = cs;
    block->phys        = phys_addr;
    block->dirty_mask  = &page->dirty_mask;
    block->dirty_mask2 = NULL;
    block->next = block->prev = BLOCK_INVALID;
    block->next_2 = block->prev_2 = BLOCK_INVALID;
    block->page_mask = block->page_mask2 = 0;
    block->flags                         = CODEBLOCK_STATIC_TOP;
    block->status                        = cpu_cur_status;

    recomp_page = block->phys & ~0xfff;
    codeblock_tree_add(block);
}

static ir_data_t *ir_data;

ir_data_t *
codegen_get_ir_data(void)
{
    return ir_data;
}

void
codegen_block_start_recompile(codeblock_t *block)
{
    page_t *page = &pages[block->phys >> 12];

    if (!page->block)
        mem_flush_write_page(block->phys, cs + cpu_state.pc);

    block_num     = HASH(block->phys);
    block_current = get_block_nr(block); // block->pnt;

#ifndef RELEASE_BUILD
    if (block->pc != cs + cpu_state.pc || (block->flags & CODEBLOCK_WAS_RECOMPILED))
        fatal("Recompile to used block!\n");
#endif

    block->head_mem_block = codegen_allocator_allocate(NULL, block_current);
    block->data           = codeblock_allocator_get_ptr(block->head_mem_block);

    block->status = cpu_cur_status;

    block->page_mask = block->page_mask2 = 0;
    block->ins                           = 0;

    cpu_block_end = 0;

    last_op32   = -1;
    last_ea_seg = NULL;
    last_ssegs  = -1;

    codegen_block_cycles = 0;
    codegen_timing_block_start();

    codegen_block_ins      = 0;
    codegen_block_full_ins = 0;

    recomp_page = block->phys & ~0xfff;

    codegen_flags_changed = 0;
    codegen_fpu_entered   = 0;
    codegen_mmx_entered   = 0;

    codegen_fpu_loaded_iq[0] = codegen_fpu_loaded_iq[1] = codegen_fpu_loaded_iq[2] = codegen_fpu_loaded_iq[3] = codegen_fpu_loaded_iq[4] = codegen_fpu_loaded_iq[5] = codegen_fpu_loaded_iq[6] = codegen_fpu_loaded_iq[7] = 0;

    cpu_state.seg_ds.checked = cpu_state.seg_es.checked = cpu_state.seg_fs.checked = cpu_state.seg_gs.checked = (cr0 & 1) ? 0 : 1;

    block->TOP = cpu_state.TOP & 7;
    block->flags |= CODEBLOCK_WAS_RECOMPILED;

    codegen_flat_ds = !(cpu_cur_status & CPU_STATUS_NOTFLATDS);
    codegen_flat_ss = !(cpu_cur_status & CPU_STATUS_NOTFLATSS);

    if (block->flags & CODEBLOCK_BYTE_MASK) {
        block->dirty_mask  = &page->byte_dirty_mask[(block->phys >> PAGE_BYTE_MASK_SHIFT) & PAGE_BYTE_MASK_OFFSET_MASK];
        block->dirty_mask2 = NULL;
    }

    ir_data        = codegen_ir_init();
    ir_data->block = block;
    codegen_reg_reset();
    codegen_accumulate_reset();
    codegen_generate_reset();
}

void
codegen_block_remove(void)
{
    codeblock_t *block = &codeblock[block_current];

    delete_block(block);

    recomp_page = -1;
}

void
codegen_block_generate_end_mask_recompile(void)
{
    codeblock_t *block = &codeblock[block_current];
    page_t      *p;

    p = &pages[block->phys >> 12];
    if (block->flags & CODEBLOCK_BYTE_MASK) {
        int offset = (block->phys >> PAGE_BYTE_MASK_SHIFT) & PAGE_BYTE_MASK_OFFSET_MASK;

        p->byte_code_present_mask[offset] |= block->page_mask;
    } else
        p->code_present_mask |= block->page_mask;

    if ((*(block->dirty_mask) & block->page_mask) && !page_in_evict_list(p))
        page_add_to_evict_list(p);

    block->phys_2 = -1;
    block->next_2 = block->prev_2 = BLOCK_INVALID;
    if (block->page_mask2) {
        block->phys_2 = get_phys_noabrt(codegen_endpc);
        if (block->phys_2 != -1) {
            page_t *page_2 = &pages[block->phys_2 >> 12];

            if (block->flags & CODEBLOCK_BYTE_MASK) {
                int offset = (block->phys_2 >> PAGE_BYTE_MASK_SHIFT) & PAGE_BYTE_MASK_OFFSET_MASK;

                page_2->byte_code_present_mask[offset] |= block->page_mask2;
                block->dirty_mask2 = &page_2->byte_dirty_mask[offset];
            } else {
                page_2->code_present_mask |= block->page_mask2;
                block->dirty_mask2 = &page_2->dirty_mask;
            }
            if (((*block->dirty_mask2) & block->page_mask2) && !page_in_evict_list(page_2))
                page_add_to_evict_list(page_2);

            if (!pages[block->phys_2 >> 12].block_2)
                mem_flush_write_page(block->phys_2, codegen_endpc);

#ifndef RELEASE_BUILD
            if (!block->page_mask2)
                fatal("!page_mask2\n");
            if (block->next_2) {
                if (codeblock[block->next_2].pc == BLOCK_PC_INVALID)
                    fatal("block->next_2->pc=BLOCK_PC_INVALID %p\n", (void *) &codeblock[block->next_2]);
            }
#endif
        } else {
            /*Second page not present. page_mask2 is most likely set only because
              the recompiler didn't know how long the last instruction was, so
              clear it*/
            block->page_mask2 = 0;
        }
    }

    recomp_page = -1;
}

void
codegen_block_generate_end_mask_mark(void)
{
    codeblock_t *block = &codeblock[block_current];
    uint32_t     start_pc;
    uint32_t     end_pc;
    page_t      *p;

#ifndef RELEASE_BUILD
    if (block->flags & CODEBLOCK_BYTE_MASK)
        fatal("codegen_block_generate_end_mask2() - BYTE_MASK\n");
#endif

    block->page_mask = 0;
    start_pc         = (block->pc & 0xfff) & ~63;
    if ((block->pc ^ codegen_endpc) & ~0xfff)
        end_pc = 0xfff & ~63;
    else
        end_pc = (codegen_endpc & 0xfff) & ~63;
    if (end_pc < start_pc)
        end_pc = 0xfff;
    start_pc >>= PAGE_MASK_SHIFT;
    end_pc >>= PAGE_MASK_SHIFT;

    for (; start_pc <= end_pc; start_pc++) {
        block->page_mask |= ((uint64_t) 1 << start_pc);
    }

    p = &pages[block->phys >> 12];
    p->code_present_mask |= block->page_mask;
    if ((p->dirty_mask & block->page_mask) && !page_in_evict_list(p))
        page_add_to_evict_list(p);

    block->phys_2     = -1;
    block->page_mask2 = 0;
    block->next_2 = block->prev_2 = BLOCK_INVALID;
    if ((block->pc ^ codegen_endpc) & ~0xfff) {
        block->phys_2 = get_phys_noabrt(codegen_endpc);
        if (block->phys_2 != -1) {
            page_t *page_2 = &pages[block->phys_2 >> 12];

            start_pc = 0;
            end_pc   = (codegen_endpc & 0xfff) >> PAGE_MASK_SHIFT;
            for (; start_pc <= end_pc; start_pc++)
                block->page_mask2 |= ((uint64_t) 1 << start_pc);

            page_2->code_present_mask |= block->page_mask2;
            if ((page_2->dirty_mask & block->page_mask2) && !page_in_evict_list(page_2))
                page_add_to_evict_list(page_2);

            if (!pages[block->phys_2 >> 12].block_2)
                mem_flush_write_page(block->phys_2, codegen_endpc);

#ifndef RELEASE_BUILD
            if (!block->page_mask2)
                fatal("!page_mask2\n");
            if (block->next_2) {
                if (codeblock[block->next_2].pc == BLOCK_PC_INVALID)
                    fatal("block->next_2->pc=BLOCK_PC_INVALID %p\n", (void *) &codeblock[block->next_2]);
            }
#endif
            block->dirty_mask2 = &page_2->dirty_mask;
        } else {
            /*Second page not present. page_mask2 is most likely set only because
              the recompiler didn't know how long the last instruction was, so
              clear it*/
            block->page_mask2 = 0;
        }
    }

    recomp_page = -1;
}

void
codegen_block_end(void)
{
    codeblock_t *block = &codeblock[block_current];

    codegen_block_generate_end_mask_mark();
    add_to_block_list(block);
}

void
codegen_block_end_recompile(codeblock_t *block)
{
    codegen_timing_block_end();
    codegen_accumulate(ir_data, ACCREG_cycles, -codegen_block_cycles);

    if (block->flags & CODEBLOCK_IN_DIRTY_LIST)
        block_dirty_list_remove(block);
    else
        remove_from_block_list(block, block->pc);
    block->next = block->prev = BLOCK_INVALID;
    block->next_2 = block->prev_2 = BLOCK_INVALID;
    codegen_block_generate_end_mask_recompile();
    add_to_block_list(block);

    if (!(block->flags & CODEBLOCK_HAS_FPU))
        block->flags &= ~CODEBLOCK_STATIC_TOP;

    codegen_accumulate_flush(ir_data);
    codegen_ir_compile(ir_data, block);
}

void
codegen_flush(void)
{
    return;
}

void
codegen_mark_code_present_multibyte(codeblock_t *block, uint32_t start_pc, int len)
{
    if (len) {
        uint32_t end_pc = start_pc + (len - 1);

        if (block->flags & CODEBLOCK_BYTE_MASK) {
            uint32_t start_pc_masked = start_pc & PAGE_MASK_MASK;
            uint32_t end_pc_masked   = end_pc & PAGE_MASK_MASK;

            if ((start_pc ^ block->pc) & ~0x3f) /*Starts in second page*/
            {
                for (; start_pc_masked <= end_pc_masked; start_pc_masked++)
                    block->page_mask2 |= ((uint64_t) 1 << start_pc_masked);
            } else if (((start_pc + (len - 1)) ^ block->pc) & ~0x3f) /*Crosses both pages*/
            {
                for (; start_pc_masked <= 63; start_pc_masked++)
                    block->page_mask |= ((uint64_t) 1 << start_pc_masked);
                for (start_pc_masked = 0; start_pc_masked <= end_pc_masked; start_pc_masked++)
                    block->page_mask2 |= ((uint64_t) 1 << start_pc_masked);
            } else /*First page only*/
            {
                for (; start_pc_masked <= end_pc_masked; start_pc_masked++)
                    block->page_mask |= ((uint64_t) 1 << start_pc_masked);
            }
        } else {
            uint32_t start_pc_shifted = start_pc >> PAGE_MASK_SHIFT;
            uint32_t end_pc_shifted   = end_pc >> PAGE_MASK_SHIFT;
            start_pc_shifted &= PAGE_MASK_MASK;
            end_pc_shifted &= PAGE_MASK_MASK;

            if ((start_pc ^ block->pc) & ~0xfff) /*Starts in second page*/
            {
                for (; start_pc_shifted <= end_pc_shifted; start_pc_shifted++)
                    block->page_mask2 |= ((uint64_t) 1 << start_pc_shifted);
            } else if (((start_pc + (len - 1)) ^ block->pc) & ~0xfff) /*Crosses both pages*/
            {
                for (; start_pc_shifted <= 63; start_pc_shifted++)
                    block->page_mask |= ((uint64_t) 1 << start_pc_shifted);
                for (start_pc_shifted = 0; start_pc_shifted <= end_pc_shifted; start_pc_shifted++)
                    block->page_mask2 |= ((uint64_t) 1 << start_pc_shifted);
            } else /*First page only*/
            {
                for (; start_pc_shifted <= end_pc_shifted; start_pc_shifted++)
                    block->page_mask |= ((uint64_t) 1 << start_pc_shifted);
            }
        }
    }
}