void GenerateAssign(Type ty, Symbol dst, int opcode, Symbol src1, Symbol src2)
{
IRInst inst;
ALLOC(inst);
dst->ref++;
src1->ref++;
if (src2) src2->ref++;
inst->ty = ty;
inst->opcode = opcode;
inst->opds[0] = dst;
inst->opds[1] = src1;
inst->opds[2] = src2;
AppendInst(inst);
DefineTemp(dst, opcode, src1, src2);
}
void GenerateFunctionCall(Type ty, Symbol recv, Symbol faddr, Vector args)
{
ILArg p;
IRInst inst;
ALLOC(inst);
if (recv) recv->ref++;
faddr->ref++;
FOR_EACH_ITEM(ILArg, p, args)
p->sym->ref++;
ENDFOR
inst->ty = ty;
inst->opcode = CALL;
inst->opds[0] = recv;
inst->opds[1] = faddr;
inst->opds[2] = (Symbol)args;
AppendInst(inst);
if (recv != NULL)
DefineTemp(recv, CALL, (Symbol)inst, NULL);
}
/* 生成赋值指令 */
void GenerateMove (Type ty, Symbol dst, Symbol src)
{
IRInst inst;
ALLOC(inst);
dst->ref++;
src->ref++;
inst->ty = ty;
inst->opcode = MOV;
inst->opds[0] = dst;
inst->opds[1] = src;
inst->opds[2] = NULL;
AppendInst (inst);
if (dst->kind == SK_Variable) {
TrackValueChange (dst);
} else if (dst->kind == SK_Temp) {
DefineTemp (dst, MOV, (Symbol)inst, NULL);
}
}
/*
* AssignInst -> VarName = Expression |
* -> VarName = Operand |
* -> *VarName = Operand
* */
void GenerateAssign (Type ty, Symbol dst, int opcode, Symbol src1, Symbol src2)
{
IRInst inst;
CALLOC(inst);
/* 符号被引用一次 */
dst->ref++;
src1->ref++;
if (src2) src2->ref++;
/* 构造三地址码 */
inst->ty = ty;
inst->opcode = opcode;
inst->opds[0] = dst;
inst->opds[1] = src1;
inst->opds[2] = src2;
/* 将三地址码添加到当前基本块中 */
AppendInst (inst);
/* 构造表达式值,并添加到dst,src1,src2的uses中 */
DefineTemp (dst, opcode, src1, src2);
}
static void PeepHole(BBlock bb)
{
IRInst inst = bb->insth.next;
IRInst ninst;
while (inst != &bb->insth)
{
ninst = inst->next;
if ((inst->opcode == CALL || (inst->opcode >= EXTI1 && inst->opcode <= CVTF8U4)) &&
ninst->opcode == MOV && inst->opds[0] == ninst->opds[1])
{
inst->opds[0]->ref -= 2;
inst->opds[0] = ninst->opds[0];
inst->next = ninst->next;
ninst->next->prev = inst;
bb->ninst--;
if (ninst->opds[0]->kind == SK_Temp)
DefineTemp(ninst->opds[0], inst->opcode, (Symbol)inst, NULL);
}
else if ((inst->opcode == MOV || inst->opcode == IMOV) && inst->opds[1]->kind == SK_Temp)
{
ValueDef def = AsVar(inst->opds[1])->def;
IRInst p;
if (def->op == MOV)
{
while (def != NULL)
{
p = (IRInst)def->src1;
p->opds[0]->ref--;
inst->opds[0]->ref++;
p->opds[0] = inst->opds[0];
p->opcode = inst->opcode;
def = def->link;
}
inst->opds[0]->ref--;
inst->opds[1]->ref--;
inst->prev->next = inst->next;
inst->next->prev = inst->prev;
}
}
else if ((inst->opcode == ADD || inst->opcode == SUB) && ninst->opcode == MOV &&
inst->opds[0] == ninst->opds[1] && inst->opds[1] == ninst->opds[0] &&
inst->opds[2]->kind == SK_Constant)
{
int tcode = TypeCode(inst->ty);
if ((tcode == F4 && inst->opds[2]->val.f == 1.0f) ||
(tcode == F8 && inst->opds[2]->val.d == 1.0) ||
(inst->opds[2]->val.i[0] == 1))
{
inst->opds[0]->ref -= 2;
inst->opds[1]->ref--;
inst->opds[2]->ref--;
inst->opcode = inst->opcode == ADD ? INC : DEC;
inst->opds[0] = inst->opds[1];
inst->opds[1] = inst->opds[2] = NULL;
inst->next = ninst->next;
ninst->next->prev = inst;
}
}
inst = inst->next;
}
}