public List <Instruction> CodeGen(int truejump, int falsejump)
{
var b = new List <Instruction>();
var f1 = S1.AsDirectField() ?? (S1.IsConstant() ? FieldSRef.Imm1() : null);
if (f1 == null)
{
f1 = FieldSRef.ScratchInt();
b.AddRange(S1.FetchToField(f1));
}
var f2 = S2.AsDirectField() ?? (S2.IsConstant() ? FieldSRef.Imm2() : null);
if (f2 == null)
{
f2 = FieldSRef.ScratchInt();
b.AddRange(S2.FetchToField(f2));
}
b.Add(new Instruction
{
opcode = Opcode.Branch,
op1 = f1,
imm1 = S1.IsConstant() ? new IntSExpr(S1.Evaluate()) : null,
op2 = f2,
imm2 = S2.IsConstant() ? new IntSExpr(S2.Evaluate()) : null,
rjmpeq = this.Op.HasFlag(CompSpec.Equal) ? truejump : falsejump,
rjmplt = this.Op.HasFlag(CompSpec.Less) ? truejump : falsejump,
rjmpgt = this.Op.HasFlag(CompSpec.Greater) ? truejump : falsejump,
});
return(b);
}
public List <Instruction> PutFromReg(RegVRef src)
{
var code = new List <Instruction>();
FieldSRef addr = this.addr as FieldSRef;
if (addr == null)
{
if (this.addr.IsConstant())
{
addr = FieldSRef.Imm1();
}
else
{
addr = FieldSRef.ScratchInt();
code.AddRange(this.addr.FetchToField(addr));
}
}
code.Add(new Instruction
{
opcode = Opcode.MemWrite,
op1 = addr,
op2 = src,
imm1 = this.addr.IsConstant() ? this.addr : null,
});
return(code);
}
public List <Instruction> FetchToReg(RegVRef dest)
{
var code = new List <Instruction>();
FieldSRef addr = this.addr.AsDirectField();
if (addr == null)
{
if (this.addr.IsConstant())
{
addr = FieldSRef.Imm1();
}
else
{
addr = FieldSRef.ScratchInt();
code.AddRange(this.addr.FetchToField(addr));
}
}
code.Add(new Instruction
{
opcode = Opcode.MemRead,
op1 = addr,
dest = dest,
imm1 = this.addr.IsConstant() ? this.addr : null,
idx = this.addr.frame(),
});
return(code);
}
public List <Instruction> FetchToField(FieldSRef dest)
{
var code = new List <Instruction>();
code.Add(new compiler.Instruction {
opcode = Opcode.Sub,
op1 = FieldSRef.Imm1(),
imm1 = this,
op2 = dest,
dest = dest,
acc = true
});
return(code);
}
public List <Instruction> PutFromInt(int value)
{
var code = new List <Instruction>();
if (varref.IsLoaded)
{
code.Add(new Instruction
{
opcode = Opcode.Sub,
imm1 = new IntSExpr(value),
op1 = FieldSRef.Imm1(),
op2 = this,
dest = this,
acc = true,
});
}
else
{
code.AddRange(this.varref.FetchToReg(RegVRef.rScratchTab));
var t = this.InRegister(RegVRef.rScratchTab);
code.Add(new Instruction
{
opcode = Opcode.Sub,
imm1 = new IntSExpr(value),
op1 = FieldSRef.Imm1(),
op2 = t,
dest = t,
acc = true,
});
code.AddRange(this.varref.PutFromReg(RegVRef.rScratchTab));
}
return(code);
}
public List <Instruction> BuildFunction()
{
var b = new List <Instruction>();
// save call site (in r8.signal-0)
b.Add(new Push(RegVRef.rScratchInts));
if (localints.Count > 0)
{
// save parent localints
b.Add(new Push(RegVRef.rLocalInts("parent")));
}
// push regs as needed
foreach (var sym in locals.Where(s => s.type == SymbolType.Register))
{
if (sym.fixedAddr.HasValue)
{
b.Add(new Push(new RegVRef(sym.fixedAddr.Value)));
}
}
// wind stack down for locals if needed
if (framesize > 0)
{
b.Add(new Instruction
{
opcode = Opcode.Add,
op1 = FieldSRef.Imm1(),
imm1 = new IntSExpr(-framesize),
acc = true,
dest = FieldSRef.Pointer(PointerIndex.CallStack)
});
}
// copy params if named
//int args or null in r8
var intparas = locals.Where(sym => sym.type == SymbolType.Parameter && sym.datatype == "int").ToList();
if (intparas.Count() > 0)
{
for (int i = 0; i < intparas.Count(); i++)
{
b.Add(new Instruction
{
opcode = Opcode.Add,
op1 = FieldSRef.IntArg(name, intparas[i].name),
dest = FieldSRef.LocalInt(name, intparas[i].name),
acc = i != 0,
});
}
}
FieldSRef.ResetScratchInts();
b.AddRange(RegVRef.rScratchInts.PutFromReg(RegVRef.rNull));
// body
b.AddRange(body.CodeGen());
// convert rjmp __return => rjmp <integer> to here.
for (int i = 0; i < b.Count; i++)
{
var inst = b[i];
if ((inst.imm1 as AddrSExpr)?.symbol == "__return")
{
inst.imm1 = new IntSExpr(b.Count - i);
}
if ((inst.imm2 as AddrSExpr)?.symbol == "__return")
{
inst.imm2 = new IntSExpr(b.Count - i);
}
b[i] = inst;
}
// wind stack back up for locals if needed
if (framesize > 0)
{
b.Add(new Instruction
{
opcode = Opcode.Add,
op1 = FieldSRef.Imm1(),
imm1 = new IntSExpr(framesize),
acc = true,
dest = FieldSRef.Pointer(PointerIndex.CallStack)
});
}
// restore registers
foreach (var sym in locals.Where(s => s.type == SymbolType.Register).Reverse())
{
if (sym.fixedAddr.HasValue)
{
b.Add(new Pop(new RegVRef(sym.fixedAddr.Value)));
}
}
if (localints.Count > 0)
{
// restore parent localints
b.Add(new Pop(RegVRef.rLocalInts("parent")));
}
// get return site
b.Add(new Exchange(RegVRef.rScratchTab));
b.Add(new Instruction
{
opcode = Opcode.Sub,
op1 = FieldSRef.VarField(RegVRef.rScratchTab, "signal-0"),
op2 = FieldSRef.CallSite,
dest = FieldSRef.CallSite,
acc = true
});
b.Add(new Pop(RegVRef.rScratchTab));
// jump to return site
b.Add(new Jump {
target = FieldSRef.CallSite
});
return(b);
}
public List <Instruction> FetchToField(FieldSRef dest)
{
var code = new List <Instruction>();
var f1 = S1.AsDirectField();
if (f1 == null)
{
if (S1.IsConstant())
{
f1 = FieldSRef.Imm1();
}
else
{
f1 = FieldSRef.ScratchInt();
code.AddRange(S1.FetchToField(f1));
}
}
var f2 = S2.AsDirectField();
if (f2 == null)
{
if (S2.IsConstant())
{
f2 = FieldSRef.Imm2();
}
else
{
f2 = FieldSRef.ScratchInt();
code.AddRange(S2.FetchToField(f2));
}
}
Opcode op;
switch (Op)
{
case ArithSpec.Add:
op = Opcode.Add;
break;
case ArithSpec.Subtract:
op = Opcode.Sub;
break;
case ArithSpec.Multiply:
op = Opcode.Mul;
break;
case ArithSpec.Divide:
op = Opcode.Div;
break;
default:
throw new InvalidOperationException();
}
var tmp = FieldSRef.ScratchInt();
code.Add(new Instruction
{
opcode = op,
op1 = f1,
imm1 = S1.IsConstant() ? S1 : null,
op2 = f2,
imm2 = S2.IsConstant() ? S2 : null,
dest = tmp,
acc = true
});
//TODO: optimize this one day?
code.AddRange(dest.PutFromField(tmp));
return(code);
}