#include "ibm.h"
#include "x86.h"
#include "386_common.h"
#include "codegen.h"
#include "codegen_ir.h"
#include "codegen_ir_defs.h"
#include "codegen_reg.h"
#include "codegen_ops_helpers.h"

void LOAD_IMMEDIATE_FROM_RAM_16_unaligned(codeblock_t *block, ir_data_t *ir, int dest_reg, uint32_t addr)
{
        /*Word access that crosses two pages. Perform reads from both pages, shift and combine*/
        uop_MOVZX_REG_PTR_8(ir, IREG_temp3_W, get_ram_ptr(addr));
        uop_MOVZX_REG_PTR_8(ir, dest_reg, get_ram_ptr(addr+1));
        uop_SHL_IMM(ir, IREG_temp3_W, IREG_temp3_W, 8);
        uop_OR(ir, dest_reg, dest_reg, IREG_temp3_W);
}

void LOAD_IMMEDIATE_FROM_RAM_32_unaligned(codeblock_t *block, ir_data_t *ir, int dest_reg, uint32_t addr)
{
        /*Dword access that crosses two pages. Perform reads from both pages, shift and combine*/
        uop_MOV_REG_PTR(ir, dest_reg, get_ram_ptr(addr & ~3));
        uop_MOV_REG_PTR(ir, IREG_temp3, get_ram_ptr((addr + 4) & ~3));
        uop_SHR_IMM(ir, dest_reg, dest_reg, (addr & 3) * 8);
        uop_SHL_IMM(ir, IREG_temp3, IREG_temp3, (4 - (addr & 3)) * 8);
        uop_OR(ir, dest_reg, dest_reg, IREG_temp3);
}

#define UNROLL_MAX_REG_REFERENCES 200
#define UNROLL_MAX_UOPS 1000
#define UNROLL_MAX_COUNT 10
int codegen_can_unroll_full(codeblock_t *block, ir_data_t *ir, uint32_t next_pc, uint32_t dest_addr)
{
        int start;
        int max_unroll;

        /*Check that dest instruction was actually compiled into block*/
        for (start = 0; start < ir->wr_pos; start++)
        {
//                pclog("  uOP %i %08x %08x\n", c, ir->uops[c].pc, dest_addr);
                if (ir->uops[start].pc == dest_addr)
                        break;
                if (ir->uops[start].pc > dest_addr)
                {
//                        pclog("Went past dest_addr. start_pc=%08x end_pc=%08x dest_pc=%08x wr_pos=%i loop_size=%i\n", block->pc-cs, next_pc, dest_addr, ir->wr_pos, ir->wr_pos-start);
                        return 0;
                }
        }
        /*Couldn't find any uOPs corresponding to the destination instruction*/
        if (start == ir->wr_pos)
        {
                /*Is instruction jumping to itself?*/
                if (dest_addr != cpu_state.oldpc)
                {
//                        pclog("Couldn't find start. start_pc=%08x end_pc=%08x dest_pc=%08x wr_pos=%i loop_size=%i\n", block->pc-cs, next_pc, dest_addr, ir->wr_pos, ir->wr_pos-start);
                        return 0;
                }
        }

        max_unroll = UNROLL_MAX_UOPS / ((ir->wr_pos-start)+6);
        if (max_unroll > (UNROLL_MAX_REG_REFERENCES / max_version_refcount))
                max_unroll = (UNROLL_MAX_REG_REFERENCES / max_version_refcount);
        if (max_unroll > UNROLL_MAX_COUNT)
                max_unroll = UNROLL_MAX_COUNT;
        if (max_unroll <= 1)
                return 0;

        codegen_ir_set_unroll(max_unroll, start);

        return 1;
}