#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;
	int first_instruction;
	int TOP = -1;

	/*Check that dest instruction was actually compiled into block*/
	start = codegen_get_instruction_uop(block, dest_addr, &first_instruction, &TOP);

	/*Couldn't find any uOPs corresponding to the destination instruction*/
	if (start == -1) {
		/*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;
		} else {
			start = ir->wr_pos;
			TOP = cpu_state.TOP;
		}
	}

	if (TOP != cpu_state.TOP)
		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, first_instruction);

	return 1;
}
