work

src/arch/mod.rs

@@ -9,5 +9,6 @@ pub trait Arch: Sized {
     const NAME: &str;
     type Asm;
     type Addr: Addr;
+    type CallConv;
     fn compile(p: &Program<Self>) -> Result<LinkedProgram<Self::Addr>, CompilerMsg>;
 }

src/arch/x86_64/compile.rs

@@ -1,14 +1,24 @@
-use std::collections::HashMap;
+use std::collections::{HashMap, HashSet};
 
 use super::*;
-use crate::backend::{LibImport, LinkedProgram, SymImport, SymTable, Symbol};
-use util::*;
+use crate::backend::{Body, Func, LibImport, LinkedProgram, SymImport, SymTable, Symbol, VarId};
 
 pub struct Encoder<'a> {
     pub code: Code,
     pub sym_tab: SymTable<u64>,
     pub sym_refs: HashMap<Symbol, Vec<usize>>,
     pub program: &'a Program<X86_64>,
+    pub active: FnData,
+}
+
+#[derive(Default)]
+struct FnData {
+    pub segs: Vec<SegUses>,
+    pub seg: usize,
+    pub i: usize,
+    pub var: HashMap<VarId, RegW>,
+    pub reg: [Option<VarId>; 16],
+    pub reg_next: [Option<RegUse>; 16],
 }
 
 pub fn compile(p: &Program<X86_64>) -> Result<LinkedProgram<u64>, CompilerMsg> {
@@ -17,11 +27,7 @@ pub fn compile(p: &Program<X86_64>) -> Result<LinkedProgram<u64>, CompilerMsg> {
     p.encode_data(&mut encoder.code.bytes, &mut encoder.sym_tab);
 
     for f in &p.funcs {
-        let addr = encoder.code.bytes.len();
-        encoder.sym_tab.insert(f.sym, addr as u64);
-        for instr in &f.instrs {
-            encoder.compile_instr(instr)?;
-        }
+        encoder.func(f);
     }
 
     for (pos, sym) in encoder.code.missing.drain(..) {
@@ -60,14 +66,228 @@ pub fn compile(p: &Program<X86_64>) -> Result<LinkedProgram<u64>, CompilerMsg> {
     })
 }
 
+#[derive(Default)]
+pub struct SegUses {
+    var: HashMap<VarId, Vec<usize>>,
+    reg: [Vec<RegUse>; 16],
+}
+
+#[derive(Clone, Copy)]
+pub struct RegUse {
+    pos: usize,
+    // required var, if any
+    var: Option<VarId>,
+}
+
 type BInstr = crate::backend::Instr<X86_64>;
 impl<'a> Encoder<'a> {
-    fn compile_instr(&mut self, instr: &BInstr) -> Result<(), CompilerMsg> {
-        match instr {
-            BInstr::Asm(asm) => {
-                self.code.extend(asm);
+    fn func(&mut self, f: &Func<X86_64>) -> ERes {
+        let addr = self.code.bytes.len();
+        self.sym_tab.insert(f.sym, addr as u64);
+        self.active = Default::default();
+        self.calc_uses(&f.body);
+        for (i, instr) in f.body.iter().enumerate() {
+            self.active.i = i;
+            let seg = &self.active.segs[self.active.seg];
+            for r in 0..self.active.reg_next.len() {
+                let u = self.active.reg_next[r];
+                let Some(u) = u else {
+                    continue;
+                };
+                if u.pos != r {
+                    continue;
+                }
+                // if there's a var currently in the reg
+                if let Some(var) = self.active.reg[r] {
+                    // done if it's what's needed
+                    if u.var.is_some_and(|v| var == v) {
+                        continue;
+                    }
+                    // otherwise save it
+                    self.save(var);
+                }
+                if let Some(var) = u.var {
+                    if let Some(cur) = self.active.var.get(&var) {}
+                }
+            }
+            match instr {
+                BInstr::Asm(asm) => self.asm(asm)?,
+                _ => todo!(),
+            }
+        }
+        Ok(())
+    }
+
+    fn save(&mut self, var: VarId) {
+        todo!()
+    }
+
+    fn calc_uses(&mut self, body: &Body<X86_64>) -> (usize, usize) {
+        let mut pos = 0;
+        let seg_i = self.active.segs.len();
+        self.active.segs.push(Default::default());
+        let mut uses = SegUses::default();
+        macro_rules! push {
+            ($var:ident) => {
+                push!($var, 0)
+            };
+            ($var:ident, $pos:expr) => {
+                uses.var.entry($var.clone()).or_default().push(pos + $pos)
+            };
+        }
+        for instr in body {
+            match instr {
+                BInstr::Set { dst, src: _ } => push!(dst),
+                BInstr::Call { dst, f, args } => {
+                    let conv = &self.program.call_convs[self.program.funcs[f].conv];
+                    push!(dst);
+
+                    for &reg in conv.scratch() {
+                        uses.reg[reg as usize].push(RegUse { pos, var: None });
+                    }
+                    for (i, &arg) in args.iter().enumerate() {
+                        push!(arg);
+                        if let Some(&reg) = conv.param().get(i) {
+                            uses.reg[reg as usize].last_mut().unwrap().var = Some(arg);
+                        }
+                    }
+                }
+                BInstr::Copy { dst, src } => {
+                    push!(dst);
+                    push!(src);
+                }
+                BInstr::Add { dst, src1, src2 } => {
+                    push!(dst);
+                    push!(src1);
+                    push!(src2);
+                }
+                BInstr::If { cond, then, else_ } => {
+                    push!(cond);
+                    pos += 1;
+                    let (seg_i1, len1) = self.calc_uses(then);
+                    let (seg_i2, len2) = self.calc_uses(else_);
+                    // insert closest usages
+                    for (var, poss1) in &self.active.segs[seg_i1].var {
+                        if let Some(poss2) = self.active.segs[seg_i2].var.get(var) {
+                            push!(var, poss1[0].min(poss2[0]));
+                        } else {
+                            push!(var, poss1[0]);
+                        }
+                    }
+                    for (var, poss2) in &self.active.segs[seg_i2].var {
+                        if !self.active.segs[seg_i1].var.contains_key(var) {
+                            push!(var, poss2[0]);
+                        }
+                    }
+                    pos += len1.max(len2);
+                    continue;
+                }
+                BInstr::Loop(instrs) => {
+                    let (seg_i2, len) = self.calc_uses(instrs);
+                    // insert closest usages
+                    for (var, poss) in &self.active.segs[seg_i2].var {
+                        push!(var, poss[0]);
+                    }
+                    // during register allocation, want to insert the first use of each var
+                    // at len + use, because if it jumps back up, that will be the next
+                    // usage rather than if the loop exits; pad ensures there is room so
+                    // the insertions are always before the rest of the usages (after loop)
+                    let pad = (len * 2).saturating_sub(pos);
+                    pos += len + pad;
+                    continue;
+                }
+                BInstr::Break(var) => {
+                    if let Some(var) = var {
+                        push!(var);
+                    }
+                }
+                BInstr::Return(var) => {
+                    if let Some(var) = var {
+                        push!(var);
+                    }
+                }
+                BInstr::Asm(asm) => {
+                    let mut used = HashSet::new();
+                    for i in &asm.instrs {
+                        if let Some(reg) = i.dst_reg() {
+                            used.insert(reg.reg());
+                        }
+                    }
+                    for &(reg, var) in &asm.args {
+                        push!(var);
+                        used.remove(&reg);
+                        uses.reg[reg as usize].push(RegUse {
+                            pos,
+                            var: Some(var),
+                        });
+                    }
+                    for reg in used {
+                        uses.reg[reg as usize].push(RegUse { pos, var: None });
+                    }
+                }
+            }
+            pos += 1;
+        }
+        self.active.segs[seg_i] = uses;
+        return (seg_i, pos);
+    }
+
+    pub fn prep_var(&mut self, var: VarId) -> RegW {
+        let seg = &mut self.active.segs[self.active.seg];
+        if let Some(reg) = self.active.var.get(&var) {
+            *reg
+        } else {
+        }
+    }
+
+    pub fn rvm(&mut self, input: Rvm) -> RegMem {
+        match input {
+            Rvm::Reg(reg) => reg.into(),
+            Rvm::Var(var) => self.prep_var(var).into(),
+            Rvm::Mem(mem) => mem.into(),
+        }
+    }
+
+    pub fn rvmi(&mut self, input: Rvmi) -> RegMemImm {
+        match input {
+            Rvmi::Reg(reg) => reg.into(),
+            Rvmi::Var(var) => self.prep_var(var).into(),
+            Rvmi::Mem(mem) => mem.into(),
+            Rvmi::Imm(imm) => imm.into(),
+        }
+    }
+
+    pub fn asm(&mut self, asm: &Asm) -> ERes {
+        let mut used = HashSet::default();
+        let mut vars = HashSet::default();
+        for &instr in &asm.instrs {
+            if let Some(regw) = instr.dst_reg() {
+                used.insert(regw.reg());
+            }
+            for var in instr.vars() {
+                vars.insert(var);
+            }
+        }
+        let overlap = used.intersection(&self.active.var.values());
+        for var in &vars {
+            if let Some(reg) = self.active.var.get(var)
+                && used.contains(reg)
+            {}
+        }
+        for &instr in &asm.instrs {
+            match instr {
+                Instr::Mov { dst, src } => self.code.mov(self.rvm(dst), self.rvmi(src))?,
+                Instr::Push(rvmi) => todo!(),
+                Instr::Pop(rvm) => todo!(),
+                Instr::Lea { dst, src } => todo!(),
+                Instr::Int(code) => self.code.int(code),
+                Instr::Syscall => self.code.syscall(),
+                Instr::Call(sym) => self.code.call(sym),
+                Instr::CallAt(sym) => self.code.call_mem(sym),
+                Instr::Ret => self.code.ret(),
+                Instr::Add { dst, src } => todo!(),
+                Instr::Sub { dst, src } => todo!(),
             }
-            _ => todo!(),
         }
         Ok(())
     }
@@ -77,6 +297,9 @@ impl<'a> Encoder<'a> {
             code: Code::default(),
             sym_tab: SymTable::new(program.sym_count()),
             sym_refs: Default::default(),
+            seg: 0,
+            segs: Default::default(),
+            active: Default::default(),
             program,
         }
     }

src/arch/x86_64/encode.rs

@@ -1,7 +1,7 @@
 use super::*;
 use crate::backend::Symbol;
 
-type ERes = Result<(), CompilerMsg>;
+pub type ERes = Result<(), CompilerMsg>;
 
 /// machine code
 #[derive(Default)]
@@ -11,25 +11,21 @@ pub struct Code {
 }
 
 impl Code {
-    pub fn mov(&mut self, dst: impl Into<RegMem>, src: impl Into<RegImmMem>) -> ERes {
+    pub fn mov(&mut self, dst: impl Into<RegMem>, src: impl Into<RegMemImm>) -> ERes {
         let dst = dst.into();
         let src = src.into();
         match dst {
             RegMem::Reg(mut dst) => match src {
-                RegImmMem::Reg(src) => {
+                RegMemImm::Reg(src) => {
                     if dst.width() != src.width() {
                         return Err("src and dst are not same width".into());
                     }
-                    if dst.incompatible(&src) {
-                        return Err("incompatible registers due to rex".into());
-                    }
-                    let width = dst.width();
-                    self.prefix16(width);
-                    self.rex(width, src, 0, dst);
-                    self.bytes.push(0x88 | width.not8());
+                    self.prefix16(dst);
+                    self.rex(dst, src, 0, dst)?;
+                    self.bytes.push(0x88 | dst.not8());
                     self.modrm(src, dst);
                 }
-                RegImmMem::Imm(src) => {
+                RegMemImm::Imm(src) => {
                     let src_width = src.width_unsigned()?;
                     if src_width > dst.width() {
                         return Err("immediate cannot fit in register".into());
@@ -44,40 +40,34 @@ impl Code {
                         if src_width <= Width::B32 {
                             dst = dst.lower64();
                         }
-                        self.rex(dst, 0, 0, dst);
+                        self.rex(dst, 0, 0, dst)?;
                         self.bytes.push(0xb0 | (dst.not8() << 3) | dst.base());
                         self.imm(src, dst.width());
                     }
                 }
-                RegImmMem::Mem(src) => {
+                RegMemImm::Mem(src) => {
                     if src.width != dst.width() {
                         return Err("register & memory sizes don't match".into());
                     }
-                    if dst.high() && src.reg.gt8() {
-                        return Err("registers incompatible (REX)".into());
-                    }
-                    self.prefix32(&src)?;
+                    self.prefix32(src)?;
                     self.prefix16(dst);
-                    self.rex(dst, dst, 0, src);
+                    self.rex(dst, dst, 0, src)?;
                     self.bytes.push(0x8a | dst.not8());
                     self.modrm(dst, src);
                 }
             },
             RegMem::Mem(dst) => match src {
-                RegImmMem::Reg(src) => {
+                RegMemImm::Reg(src) => {
                     if src.width() != dst.width {
                         return Err("register & memory sizes don't match".into());
                     }
-                    if src.high() && dst.reg.gt8() {
-                        return Err("registers incompatible (REX)".into());
-                    }
-                    self.prefix32(&dst)?;
+                    self.prefix32(dst)?;
                     self.prefix16(src);
-                    self.rex(dst, src, 0, dst);
+                    self.rex(dst, src, 0, dst)?;
                     self.bytes.push(0x88 | src.not8());
                     self.modrm(src, dst);
                 }
-                RegImmMem::Imm(src) => {
+                RegMemImm::Imm(src) => {
                     let encode_width = dst.width.min(Width::B32);
                     let src_width = if dst.width == Width::B64 {
                         src.width_signed()
@@ -90,32 +80,32 @@ impl Code {
                     if src_width > dst.width {
                         return Err("source cannot fit in destination".into());
                     }
-                    self.prefix32(&dst)?;
+                    self.prefix32(dst)?;
                     self.prefix16(encode_width);
-                    self.rex(dst, 0, 0, dst);
+                    self.rex(dst, 0, 0, dst)?;
                     self.bytes.push(0xc6 | encode_width.not8());
                     self.modrm(0, dst);
                     self.imm(src, encode_width);
                 }
-                RegImmMem::Mem(_) => return Err("cannot move memory to memory".into()),
+                RegMemImm::Mem(_) => return Err("cannot move memory to memory".into()),
             },
         }
         Ok(())
     }
 
-    pub fn push(&mut self, reg: impl Into<RegImmMem>) -> ERes {
+    pub fn push(&mut self, reg: impl Into<RegMemImm>) -> ERes {
         match reg.into() {
-            RegImmMem::Reg(reg) => match reg.width() {
+            RegMemImm::Reg(reg) => match reg.width() {
                 Width::B64 => {
                     if reg.gt8() {
                         self.bytes.push(0x41);
                     }
                     self.bytes.push(0x50 | reg.base());
                 }
-                Width::B16 => {}
+                Width::B16 => todo!(),
                 _ => return Err("register must be 64 or 16 bit".into()),
             },
-            RegImmMem::Imm(imm) => match imm.width_unsigned()? {
+            RegMemImm::Imm(imm) => match imm.width_unsigned()? {
                 Width::B8 => {
                     self.bytes.push(0x6a);
                     self.bytes.push(imm.0 as u8);
@@ -126,12 +116,12 @@ impl Code {
                 }
                 Width::B64 => return Err("immediate must be 32 bit or less".into()),
             },
-            RegImmMem::Mem(mem) => todo!(),
+            RegMemImm::Mem(mem) => todo!(),
         }
         Ok(())
     }
 
-    pub fn pop(&mut self, reg: Reg) -> ERes {
+    pub fn pop(&mut self, reg: RegW) -> ERes {
         match reg.width() {
             Width::B64 | Width::B16 => (),
             _ => return Err("register must be 64 or 16 bit".into()),
@@ -144,10 +134,11 @@ impl Code {
         Ok(())
     }
 
-    pub fn lea(&mut self, dst: Reg, sym: Symbol) {
-        self.rex(1, dst, 0, 0);
+    pub fn lea(&mut self, dst: RegW, sym: Symbol) -> ERes {
+        self.rex(1, dst, 0, 0)?;
         self.bytes.push(0x8d);
         self.modrm(dst, sym);
+        Ok(())
     }
 
     pub fn int(&mut self, code: u8) {
@@ -172,42 +163,69 @@ impl Code {
         self.bytes.push(0xc3);
     }
 
-    fn add_sub(&mut self, dst: Reg, src: impl Into<Imm>, ext: u8) -> ERes {
-        let mut src = src.into();
-        let mut width = src.width_signed()?;
-        let dst_width = dst.width().min(Width::B32);
-
-        self.prefix16(dst_width);
-        self.rex(dst, 0, 0, dst);
-
-        if width > dst_width {
-            width = src.width_unsigned()?;
-            if dst.width() == Width::B64 || width > dst_width {
-                return Err("immediate overflow".into());
+    fn add_sub(&mut self, dst: impl Into<RegMem>, src: impl Into<RegMemImm>, ext: u8) -> ERes {
+        let dst = dst.into();
+        match src.into() {
+            RegMemImm::Reg(src) => {
+                if src.width() != dst.width() {
+                    return Err("incompatible widths".into());
+                }
+                self.prefix32(dst)?;
+                self.prefix16(src);
+                self.rex(dst, src, 0, dst)?;
+                self.bytes.push(src.not8());
+                self.modrm(src, dst);
             }
-            src = src.reinterpret(dst_width);
-            width = src.width_signed()?;
-        }
+            RegMemImm::Imm(mut src) => {
+                let mut imm_width = src.width_signed()?;
+                let dst_width = dst.width().min(Width::B32);
 
-        if dst.width() == Width::B8 {
-            self.bytes.push(0x80);
-        } else if width == Width::B8 {
-            self.bytes.push(0x83);
-        } else {
-            self.bytes.push(0x81);
-            width = dst_width;
-        }
+                if imm_width > dst_width {
+                    imm_width = src.width_unsigned()?;
+                    if dst.width() == Width::B64 || imm_width > dst_width {
+                        return Err("immediate overflow".into());
+                    }
+                    src = src.reinterpret(dst_width);
+                    imm_width = src.width_signed()?;
+                }
+                let code = if dst.width() == Width::B8 {
+                    0x80
+                } else if imm_width == Width::B8 {
+                    0x83
+                } else {
+                    imm_width = dst_width;
+                    0x81
+                };
 
-        self.modrm(ext, dst);
-        self.imm(src, width);
+                self.prefix32(dst)?;
+                self.prefix16(dst_width);
+                self.rex(dst, 0, 0, dst)?;
+                self.bytes.push(code);
+                self.modrm(ext, dst);
+                self.imm(src, imm_width);
+            }
+            RegMemImm::Mem(src) => {
+                let RegMem::Reg(dst) = dst else {
+                    return Err("cannot add memory to memory".into());
+                };
+                if src.width != dst.width() {
+                    return Err("incompatible widths".into());
+                }
+                self.prefix32(src)?;
+                self.prefix16(dst);
+                self.rex(dst, dst, 0, src)?;
+                self.bytes.push(0x2 | dst.not8());
+                self.modrm(dst, src);
+            }
+        }
         Ok(())
     }
 
-    pub fn add(&mut self, dst: Reg, src: impl Into<Imm>) -> ERes {
+    pub fn add(&mut self, dst: impl Into<RegMem>, src: impl Into<RegMemImm>) -> ERes {
         self.add_sub(dst, src, 0)
     }
 
-    pub fn sub(&mut self, dst: Reg, src: impl Into<Imm>) -> ERes {
+    pub fn sub(&mut self, dst: impl Into<RegMem>, src: impl Into<RegMemImm>) -> ERes {
         self.add_sub(dst, src, 5)
     }
 
@@ -217,7 +235,10 @@ impl Code {
         }
     }
 
-    fn prefix32(&mut self, mem: &Mem) -> Result<(), CompilerMsg> {
+    fn prefix32(&mut self, mem: impl MaybeMem) -> Result<(), CompilerMsg> {
+        let Some(mem) = mem.mem() else {
+            return Ok(());
+        };
         match mem.reg.width() {
             Width::B8 | Width::B16 => return Err("invalid register width".into()),
             Width::B32 => self.bytes.push(0x67),
@@ -226,10 +247,14 @@ impl Code {
         Ok(())
     }
 
-    fn rex(&mut self, w: impl RexW, r: impl RexBit, x: u8, b: impl RexBit) {
-        if w.rexw() || r.rex() || x.rex() || b.rex() | r.req() | b.req() {
+    fn rex(&mut self, w: impl RexW, r: impl RexBit, x: u8, b: impl RexBit) -> ERes {
+        if r.req() && b.req_no() || r.req_no() && b.req() {
+            return Err("registers incompatible (REX)".into());
+        }
+        if w.rexw() || r.rex() || x.rex() || b.rex() || r.req() || b.req() {
             self.bytes.push(rex(w, r, x, b));
         }
+        Ok(())
     }
 
     fn modrm(&mut self, reg: impl ModRMReg, rm: impl ModRMRM) {

src/arch/x86_64/mod.rs

@@ -1,6 +1,5 @@
 mod compile;
 mod encode;
-mod reg;
 #[cfg(test)]
 mod test;
 mod types;
@@ -14,7 +13,6 @@ use crate::{
 
 pub use compile::*;
 pub use encode::*;
-pub use reg::*;
 pub use types::*;
 use util::*;
 
@@ -22,9 +20,35 @@ pub struct X86_64;
 
 impl Arch for X86_64 {
     const NAME: &str = "x86_64";
-    type Asm = Code;
+    type Asm = Asm;
     type Addr = u64;
+    type CallConv = CallConv;
     fn compile(p: &Program<Self>) -> Result<LinkedProgram<Self::Addr>, CompilerMsg> {
         compile(p)
     }
 }
+
+pub enum CallConv {
+    SystemV,
+}
+
+impl CallConv {
+    pub fn param(&self) -> &[Reg] {
+        use regs::*;
+        match self {
+            Self::SystemV => &[rdi, rsi, rdx, rcx, r8, r9],
+        }
+    }
+    pub fn scratch(&self) -> &[Reg] {
+        use regs::*;
+        match self {
+            Self::SystemV => &[rax, rdi, rsi, rdx, rcx, r8, r9, r10, r11],
+        }
+    }
+    pub fn ret(&self) -> &[Reg] {
+        use regs::*;
+        match self {
+            Self::SystemV => &[rax, rdx],
+        }
+    }
+}

src/arch/x86_64/reg.rs

@@ -1,197 +0,0 @@
-#[derive(Clone, Copy, PartialEq)]
-pub struct Reg {
-    val: u8,
-    high: bool,
-    width: Width,
-}
-
-#[derive(Debug, Clone, Copy, PartialEq, PartialOrd)]
-#[repr(u8)]
-pub enum Width {
-    B8 = 0,
-    B16 = 1,
-    B32 = 2,
-    B64 = 3,
-}
-
-def_regs! {
-    0b0000 : rax eax ax al,
-    0b0001 : rcx ecx cx cl !_,
-    0b0010 : rdx edx dx dl,
-    0b0011 : rbx ebx bx bl,
-
-    0b0100 : rsp esp sp spl norex=ah !_,
-    0b0101 : rbp ebp bp bpl norex=ch,
-    0b0110 : rsi esi si sil norex=dh !_,
-    0b0111 : rdi edi di dil norex=bh,
-
-    0b1000 : r8  r8d  r8w  r8b,
-    0b1001 : r9  r9d  r9w  r9b !_,
-    0b1010 : r10 r10d r10w r10b,
-    0b1011 : r11 r11d r11w r11b,
-    0b1100 : r12 r12d r12w r12b !_,
-    0b1101 : r13 r13d r13w r13b,
-    0b1110 : r14 r14d r14w r14b,
-    0b1111 : r15 r15d r15w r15b,
-}
-
-impl Reg {
-    pub fn base(&self) -> u8 {
-        self.val & 0b111
-    }
-    /// checks if register is not one of the first 8 (0-7)
-    pub fn gt8(&self) -> bool {
-        self.val >= 0b1000
-    }
-    pub fn gt4(&self) -> bool {
-        self.val >= 0b0100
-    }
-
-    pub fn width(&self) -> Width {
-        self.width
-    }
-
-    pub fn not8(&self) -> u8 {
-        self.width.not8()
-    }
-
-    pub fn high(&self) -> bool {
-        self.high
-    }
-
-    /// if self has 64 bit width, changes width to 32 bit
-    pub fn lower64(&self) -> Self {
-        let mut new = *self;
-        new.width = new.width.min(Width::B32);
-        new
-    }
-
-    pub fn requires_rex(&self) -> bool {
-        self.gt8()
-            || self.width == Width::B64
-            || (self.gt4() && self.width == Width::B8 && !self.high)
-    }
-
-    pub fn incompatible(&self, other: &Reg) -> bool {
-        (self.requires_rex() && other.high) || (self.high && other.requires_rex())
-    }
-
-    const fn new(val: u8, width: Width, high: bool) -> Self {
-        Self { val, high, width }
-    }
-}
-
-impl Width {
-    pub const fn max_val(&self) -> u64 {
-        match self {
-            Self::B64 => u64::MAX,
-            Self::B32 => u32::MAX as u64,
-            Self::B16 => u16::MAX as u64,
-            Self::B8 { .. } => u8::MAX as u64,
-        }
-    }
-
-    pub fn min(self, other: Self) -> Self {
-        if self <= other { self } else { other }
-    }
-
-    pub const fn bytes(&self) -> usize {
-        match self {
-            Self::B64 => 8,
-            Self::B32 => 4,
-            Self::B16 => 2,
-            Self::B8 { .. } => 1,
-        }
-    }
-
-    /// greater than 8 bits
-    pub const fn not8(&self) -> u8 {
-        !matches!(self, Self::B8) as u8
-    }
-}
-
-macro_rules! filter {
-    ($($filtered:ident)*; ! $_:tt $($item:ident)*; $($rest:tt)*) => {
-        filter!($($filtered)* $($item)*; $($rest)*)
-    };
-    ($($filtered:ident)*; $($item:ident)*; $($rest:tt)*) => {
-        filter!($($filtered)*; $($rest)*)
-    };
-    ($($filtered:ident)*;) => {
-        [$($filtered, )*]
-    };
-}
-use filter;
-
-macro_rules! def_regs {
-    ($($val:literal : $B64:ident $B32:ident $B16:ident $B8:ident $(norex=$B8H:ident)? $(!$imp:tt)?,)*) => {
-        $(
-        #[allow(non_upper_case_globals)]
-        pub const $B64: Reg = Reg::new($val, Width::B64, false);
-        #[allow(non_upper_case_globals)]
-        pub const $B32: Reg = Reg::new($val, Width::B32, false);
-        #[allow(non_upper_case_globals)]
-        pub const $B16: Reg = Reg::new($val, Width::B16, false);
-        #[allow(non_upper_case_globals)]
-        pub const $B8 : Reg = Reg::new($val, Width::B8 , false);
-        $(
-        #[allow(non_upper_case_globals)]
-        pub const $B8H: Reg = Reg::new($val, Width::B8, true);
-        )?
-        )*
-
-        impl Reg {
-            // #[cfg(test)]
-            // pub const ALL: &[Reg] = &[
-            //     $( $B64, $B32, $B16, $B8, $($B8H,)? )*
-            // ];
-
-            #[cfg(test)]
-            pub const IMPORTANT: &[Reg] = &
-                filter!(; $($(!$imp)? $B64 $B32 $B16 $B8 $($B8H)?; )* )
-            ;
-
-            pub fn parse(s: &str) -> Option<Self> {
-                Some(match s.to_lowercase().as_str() {
-                    $(
-                    stringify!($B64) => $B64,
-                    stringify!($B32) => $B32,
-                    stringify!($B16) => $B16,
-                    stringify!($B8 ) => $B8,
-                    $(
-                    stringify!($B8H) => $B8H,
-                    )?
-                    )*
-                    _ => return None,
-                })
-            }
-        }
-        impl std::fmt::Display for Reg {
-            #[allow(non_upper_case_globals)]
-            fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-                write!(f, "{}", match *self {
-                    $(
-                    $B64 => stringify!($B64),
-                    $B32 => stringify!($B32),
-                    $B16 => stringify!($B16),
-                    $B8  => stringify!($B8),
-                    $(
-                    $B8H => stringify!($B8H),
-                    )?
-                    )*
-                    _ => "UNKNOWN",
-                })
-            }
-        }
-    };
-}
-
-use def_regs;
-
-use crate::arch::x86_64::Imm;
-
-impl From<Reg> for Width {
-    fn from(value: Reg) -> Self {
-        value.width
-    }
-}

src/arch/x86_64/test/asm/mod.rs

@@ -38,14 +38,40 @@ fn mov() {
 
 #[test]
 fn add_sub() {
-    let c = &mut TestCtx::new("mov");
+    let c = &mut TestCtx::new("add_sub");
 
+    // add
     for dst in regs() {
         for src in imms() {
             eq(c, format!("add {dst}, {src}"), |c| c.add(dst, src))
         }
     }
 
+    for dst in regs() {
+        for src in regs() {
+            eq(c, format!("add {dst}, {src}"), |c| c.add(dst, src))
+        }
+    }
+
+    for dst in regs() {
+        for src in mems() {
+            eq(c, format!("add {dst}, {src}"), |c| c.add(dst, src))
+        }
+    }
+
+    for dst in mems() {
+        for src in imms() {
+            eq(c, format!("add {dst}, {src}"), |c| c.add(dst, src))
+        }
+    }
+
+    for dst in mems() {
+        for src in regs() {
+            eq(c, format!("add {dst}, {src}"), |c| c.add(dst, src))
+        }
+    }
+
+    // sub
     for dst in regs() {
         for src in imms() {
             eq(c, format!("sub {dst}, {src}"), |c| c.sub(dst, src))

src/arch/x86_64/test/asm/setup.rs

@@ -36,13 +36,13 @@ pub fn imms() -> impl Iterator<Item = i128> {
     IMMS.iter().cloned()
 }
 
-pub fn regs() -> impl Iterator<Item = Reg> {
-    Reg::IMPORTANT.iter().cloned()
+pub fn regs() -> impl Iterator<Item = RegW> {
+    RegW::IMPORTANT.iter().cloned()
 }
 
 pub fn mems() -> impl Iterator<Item = Mem> {
     gen move {
-        for &reg in Reg::IMPORTANT {
+        for &reg in RegW::IMPORTANT {
             for &disp in DISPS {
                 for &width in WIDTHS {
                     yield mem(reg, disp, width);
@@ -59,42 +59,62 @@ pub struct TestCtx {
     changed: bool,
 }
 
+#[track_caller]
 pub fn eq(
     ctx: &mut TestCtx,
     asm: impl AsRef<str>,
-    instr: impl FnOnce(&mut Code) -> Result<(), CompilerMsg>,
+    instr: impl Fn(&mut Code) -> Result<(), CompilerMsg>,
 ) {
     let asm = asm.as_ref();
-    let expected = if let Some(val) = ctx.cache.get(asm) {
-        val
+    let (mut res, cache) = eq_(ctx, asm, &instr);
+    if res.is_err() && cache {
+        ctx.cache.remove(asm);
+        res = eq_(ctx, asm, &instr).0;
+    }
+    if let Err(err) = res {
+        panic!("{err}");
+    }
+}
+
+#[track_caller]
+pub fn eq_(
+    ctx: &mut TestCtx,
+    asm: &str,
+    instr: impl FnOnce(&mut Code) -> Result<(), CompilerMsg>,
+) -> (Result<(), String>, bool) {
+    let (expected, cache) = if let Some(val) = ctx.cache.get(asm) {
+        (val, true)
     } else {
         ctx.changed = true;
         let res = nasm(asm);
         ctx.cache.insert(asm.to_string(), res);
-        ctx.cache.get(asm).unwrap()
+        (ctx.cache.get(asm).unwrap(), false)
     };
     let code = &mut ctx.code;
     let res = instr(code);
-    match (expected, res) {
-        (Ok(expected), Err(e)) => {
-            panic!(
-                "{asm}: failed to compile: {}\nexpected: {expected:x?}",
-                e.msg
-            );
-        }
+    let res = match (expected, res) {
+        (Ok(expected), Err(e)) => Err(format!(
+            "{asm}: failed to compile: {}\nexpected: {expected:x?}",
+            e.msg
+        )),
         (Err(e), Ok(_)) => {
             let res = &code.bytes[..];
-            panic!("{asm}: should not have compiled:\n{e}\ngot: {res:x?}");
+            Err(format!(
+                "{asm}: should not have compiled:\n{e}\ngot: {res:x?}"
+            ))
         }
-        (Err(_), Err(_)) => (),
+        (Err(_), Err(_)) => Ok(()),
         (Ok(expected), Ok(_)) => {
             let res = &code.bytes[..];
             if expected != res {
-                panic!("{asm}: expected {expected:x?}, got {res:x?}")
+                Err(format!("{asm}: expected {expected:x?}, got {res:x?}"))
+            } else {
+                Ok(())
             }
         }
-    }
-    code.bytes.clear();
+    };
+    ctx.code.bytes.clear();
+    (res, cache)
 }
 
 fn nasm(input: &str) -> Result<Vec<u8>, String> {

src/arch/x86_64/types/arg.rs

@@ -0,0 +1,292 @@
+use super::*;
+use crate::backend::Symbol;
+
+#[derive(Clone, Copy)]
+pub enum RegMem {
+    Reg(RegW),
+    Mem(Mem),
+}
+
+#[derive(Clone, Copy)]
+pub enum RegMemImm {
+    Reg(RegW),
+    Imm(Imm),
+    Mem(Mem),
+}
+
+pub trait MaybeMem {
+    fn mem(&self) -> Option<Mem>;
+}
+
+impl RegMem {
+    pub fn width(&self) -> Width {
+        match self {
+            RegMem::Reg(reg_w) => reg_w.width(),
+            RegMem::Mem(mem) => mem.width,
+        }
+    }
+}
+
+impl MaybeMem for RegW {
+    fn mem(&self) -> Option<Mem> {
+        None
+    }
+}
+
+impl MaybeMem for Mem {
+    fn mem(&self) -> Option<Mem> {
+        Some(*self)
+    }
+}
+
+impl MaybeMem for RegMem {
+    fn mem(&self) -> Option<Mem> {
+        match self {
+            RegMem::Reg(reg_w) => None,
+            RegMem::Mem(mem) => Some(*mem),
+        }
+    }
+}
+
+impl RexW for RegMem {
+    fn rexw(&self) -> bool {
+        match self {
+            RegMem::Reg(reg_w) => reg_w.rexw(),
+            RegMem::Mem(mem) => mem.rexw(),
+        }
+    }
+}
+
+impl RexBit for RegMem {
+    fn rex(&self) -> bool {
+        match self {
+            RegMem::Reg(reg_w) => reg_w.rex(),
+            RegMem::Mem(mem) => mem.rex(),
+        }
+    }
+}
+
+impl ModRMRM for RegMem {
+    fn rm(&self) -> u8 {
+        match self {
+            RegMem::Reg(reg_w) => reg_w.rm(),
+            RegMem::Mem(mem) => mem.rm(),
+        }
+    }
+
+    fn addr(&self) -> EffAddr {
+        match self {
+            RegMem::Reg(reg_w) => reg_w.addr(),
+            RegMem::Mem(mem) => mem.addr(),
+        }
+    }
+}
+
+// fromrot
+impl From<RegW> for RegMemImm {
+    fn from(value: RegW) -> Self {
+        Self::Reg(value)
+    }
+}
+
+impl From<RegW> for RegMem {
+    fn from(value: RegW) -> Self {
+        Self::Reg(value)
+    }
+}
+
+impl From<Mem> for RegMemImm {
+    fn from(value: Mem) -> Self {
+        Self::Mem(value)
+    }
+}
+
+impl From<Mem> for RegMem {
+    fn from(value: Mem) -> Self {
+        Self::Mem(value)
+    }
+}
+
+impl From<u64> for RegMemImm {
+    fn from(value: u64) -> Self {
+        Self::Imm(value.into())
+    }
+}
+
+impl From<i64> for RegMemImm {
+    fn from(value: i64) -> Self {
+        Self::Imm(value.into())
+    }
+}
+
+impl From<i32> for RegMemImm {
+    fn from(value: i32) -> Self {
+        Self::Imm(value.into())
+    }
+}
+
+impl From<i128> for RegMemImm {
+    fn from(value: i128) -> Self {
+        Self::Imm(value.into())
+    }
+}
+
+impl From<Imm> for RegMemImm {
+    fn from(value: Imm) -> Self {
+        Self::Imm(value)
+    }
+}
+
+pub trait ModRMRM {
+    fn rm(&self) -> u8;
+    fn addr(&self) -> EffAddr;
+}
+
+pub enum EffAddr {
+    Mem0,
+    Mem8(i8),
+    Mem32(i32),
+    Sym(Symbol),
+    None,
+}
+
+impl ModRMRM for RegW {
+    fn rm(&self) -> u8 {
+        self.base()
+    }
+    fn addr(&self) -> EffAddr {
+        EffAddr::None
+    }
+}
+
+impl ModRMRM for Mem {
+    fn rm(&self) -> u8 {
+        self.reg.base()
+    }
+    fn addr(&self) -> EffAddr {
+        const I8_MIN: i32 = i8::MIN as i32;
+        const I8_MAX: i32 = i8::MAX as i32;
+        let disp = self.disp;
+        match disp {
+            0 => {
+                if self.reg.base() == 0b101 {
+                    EffAddr::Mem8(0)
+                } else {
+                    EffAddr::Mem0
+                }
+            }
+            I8_MIN..=I8_MAX => EffAddr::Mem8(disp as i8),
+            _ => EffAddr::Mem32(disp),
+        }
+    }
+}
+
+impl ModRMRM for i32 {
+    fn rm(&self) -> u8 {
+        0b101
+    }
+    fn addr(&self) -> EffAddr {
+        EffAddr::Mem32(*self)
+    }
+}
+
+impl ModRMRM for Symbol {
+    fn rm(&self) -> u8 {
+        0b101
+    }
+
+    fn addr(&self) -> EffAddr {
+        EffAddr::Sym(*self)
+    }
+}
+
+impl ModRMReg for u8 {
+    fn val(&self) -> u8 {
+        *self
+    }
+}
+
+impl ModRMReg for RegW {
+    fn val(&self) -> u8 {
+        self.base()
+    }
+}
+
+pub trait ModRMReg {
+    fn val(&self) -> u8;
+}
+
+#[inline(always)]
+pub fn rex(w: impl RexW, r: impl RexBit, x: u8, b: impl RexBit) -> u8 {
+    0b0100_0000 | bit(w.rexw(), 3) | bit(r.rex(), 2) | bit(x.rex(), 1) | bit(b.rex(), 0)
+}
+
+#[inline(always)]
+fn bit(val: bool, pos: u8) -> u8 {
+    (val as u8) << pos
+}
+
+pub trait RexBit: Sized {
+    fn rex(&self) -> bool;
+    fn req(&self) -> bool {
+        false
+    }
+    fn req_no(&self) -> bool {
+        false
+    }
+}
+
+impl RexBit for u8 {
+    fn rex(&self) -> bool {
+        *self != 0
+    }
+}
+
+impl RexBit for RegW {
+    fn rex(&self) -> bool {
+        self.gt8()
+    }
+    fn req(&self) -> bool {
+        self.gt4() && (self.width() == Width::B8) && !self.high()
+    }
+    fn req_no(&self) -> bool {
+        self.high()
+    }
+}
+
+impl RexBit for Mem {
+    fn rex(&self) -> bool {
+        self.reg.rex()
+    }
+    fn req(&self) -> bool {
+        self.reg.gt8()
+    }
+}
+
+pub trait RexW {
+    fn rexw(&self) -> bool;
+}
+
+impl RexW for Width {
+    fn rexw(&self) -> bool {
+        *self == Width::B64
+    }
+}
+
+impl RexW for RegW {
+    fn rexw(&self) -> bool {
+        self.width().rexw()
+    }
+}
+
+impl RexW for u8 {
+    fn rexw(&self) -> bool {
+        *self == 1
+    }
+}
+
+impl RexW for Mem {
+    fn rexw(&self) -> bool {
+        self.width.rexw()
+    }
+}

src/arch/x86_64/types/asm.rs

@@ -0,0 +1,128 @@
+use super::*;
+use crate::backend::{Symbol, VarId};
+
+pub struct Asm {
+    pub args: Vec<(Reg, VarId)>,
+    pub instrs: Vec<Instr>,
+}
+
+pub enum Instr {
+    Mov { dst: Rvm, src: Rvmi },
+    Push(Rvmi),
+    Pop(Rvm),
+    Lea { dst: Rv, src: Symbol },
+    Int(u8),
+    Syscall,
+    Call(Symbol),
+    CallAt(Symbol),
+    Ret,
+    Add { dst: Rvm, src: Rvmi },
+    Sub { dst: Rvm, src: Rvmi },
+}
+
+impl Instr {
+    pub fn dst_reg(&self) -> Option<RegW> {
+        match self {
+            Instr::Mov { dst, src: _ } => dst.reg(),
+            Instr::Push(_) => None,
+            Instr::Pop(dst) => dst.reg(),
+            Instr::Lea { dst, src: _ } => dst.reg(),
+            Instr::Int(_) => None,
+            Instr::Syscall => None,
+            Instr::Call(_) => None,
+            Instr::CallAt(_) => None,
+            Instr::Ret => None,
+            Instr::Add { dst, src: _ } => dst.reg(),
+            Instr::Sub { dst, src: _ } => dst.reg(),
+        }
+    }
+    pub fn vars(&self) -> impl Iterator<Item = VarId> {
+        let mut vars = (None, None);
+        match self {
+            Instr::Mov { dst, src } => vars = (dst.var(), src.var()),
+            Instr::Push(src) => vars.0 = src.var(),
+            Instr::Pop(dst) => vars.0 = dst.var(),
+            Instr::Lea { dst, .. } => vars.0 = dst.var(),
+            Instr::Int(_) => (),
+            Instr::Syscall => (),
+            Instr::Call(_) => (),
+            Instr::CallAt(_) => (),
+            Instr::Ret => (),
+            Instr::Add { dst, src } => vars = (dst.var(), src.var()),
+            Instr::Sub { dst, src } => vars = (dst.var(), src.var()),
+        }
+        vars.0.into_iter().chain(vars.1)
+    }
+}
+
+#[derive(Clone, Copy)]
+pub enum Rv {
+    Reg(RegW),
+    Var(VarId),
+}
+
+#[derive(Clone, Copy)]
+pub enum Rvm {
+    Reg(RegW),
+    Var(VarId),
+    Mem(Mem),
+}
+
+#[derive(Clone, Copy)]
+pub enum Rvmi {
+    Reg(RegW),
+    Var(VarId),
+    Mem(Mem),
+    Imm(Imm),
+}
+
+impl Rv {
+    pub fn reg(&self) -> Option<RegW> {
+        if let &Self::Reg(v) = self {
+            Some(v)
+        } else {
+            None
+        }
+    }
+    pub fn var(&self) -> Option<VarId> {
+        if let &Self::Var(v) = self {
+            Some(v)
+        } else {
+            None
+        }
+    }
+}
+
+impl Rvm {
+    pub fn reg(&self) -> Option<RegW> {
+        if let &Self::Reg(v) = self {
+            Some(v)
+        } else {
+            None
+        }
+    }
+    pub fn var(&self) -> Option<VarId> {
+        if let &Self::Var(v) = self {
+            Some(v)
+        } else {
+            None
+        }
+    }
+}
+
+impl Rvmi {
+    pub fn reg(&self) -> Option<RegW> {
+        if let &Self::Reg(v) = self {
+            Some(v)
+        } else {
+            None
+        }
+    }
+    pub fn var(&self) -> Option<VarId> {
+        if let &Self::Var(v) = self {
+            Some(v)
+        } else {
+            None
+        }
+    }
+}

src/arch/x86_64/types/imm.rs

@@ -1,34 +1,10 @@
+use super::Width;
+use crate::io::CompilerMsg;
 use std::num::TryFromIntError;
 
-use super::*;
-
-#[derive(Clone, Copy)]
-pub struct Mem {
-    pub reg: Reg,
-    pub disp: i32,
-    pub width: Width,
-}
-
-#[derive(Clone, Copy)]
-pub enum RegImmMem {
-    Reg(Reg),
-    Imm(Imm),
-    Mem(Mem),
-}
-
-#[derive(Clone, Copy)]
-pub enum RegMem {
-    Reg(Reg),
-    Mem(Mem),
-}
-
 #[derive(Clone, Copy, PartialEq, PartialOrd)]
 pub struct Imm(pub i128);
 
-pub fn mem(reg: Reg, disp: i32, width: Width) -> Mem {
-    Mem { reg, disp, width }
-}
-
 impl Imm {
     pub fn overflow_msg() -> CompilerMsg {
         "immediate overflow".into()
@@ -72,68 +48,6 @@ impl TryFrom<Imm> for u8 {
     }
 }
 
-impl std::fmt::Display for Mem {
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        let Mem { reg, disp, width } = *self;
-        let size = match width {
-            Width::B8 => "BYTE",
-            Width::B16 => "WORD",
-            Width::B32 => "DWORD",
-            Width::B64 => "QWORD",
-        };
-        write!(f, "{size} [{reg} {}]", signed_hex(disp as i128, true))
-    }
-}
-
-// fromrot
-impl From<Reg> for RegImmMem {
-    fn from(value: Reg) -> Self {
-        Self::Reg(value)
-    }
-}
-
-impl From<Reg> for RegMem {
-    fn from(value: Reg) -> Self {
-        Self::Reg(value)
-    }
-}
-
-impl From<Mem> for RegImmMem {
-    fn from(value: Mem) -> Self {
-        Self::Mem(value)
-    }
-}
-
-impl From<Mem> for RegMem {
-    fn from(value: Mem) -> Self {
-        Self::Mem(value)
-    }
-}
-
-impl From<u64> for RegImmMem {
-    fn from(value: u64) -> Self {
-        Self::Imm(value.into())
-    }
-}
-
-impl From<i64> for RegImmMem {
-    fn from(value: i64) -> Self {
-        Self::Imm(value.into())
-    }
-}
-
-impl From<i32> for RegImmMem {
-    fn from(value: i32) -> Self {
-        Self::Imm(value.into())
-    }
-}
-
-impl From<i128> for RegImmMem {
-    fn from(value: i128) -> Self {
-        Self::Imm(value.into())
-    }
-}
-
 impl From<u64> for Imm {
     fn from(value: u64) -> Self {
         Self(value as i128)

src/arch/x86_64/types/mem.rs

@@ -0,0 +1,27 @@
+use crate::arch::x86_64::util::signed_hex;
+
+use super::*;
+
+#[derive(Clone, Copy)]
+pub struct Mem {
+    pub reg: RegW,
+    pub disp: i32,
+    pub width: Width,
+}
+
+pub fn mem(reg: RegW, disp: i32, width: Width) -> Mem {
+    Mem { reg, disp, width }
+}
+
+impl std::fmt::Display for Mem {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        let Mem { reg, disp, width } = *self;
+        let size = match width {
+            Width::B8 => "BYTE",
+            Width::B16 => "WORD",
+            Width::B32 => "DWORD",
+            Width::B64 => "QWORD",
+        };
+        write!(f, "{size} [{reg} {}]", signed_hex(disp as i128, true))
+    }
+}

src/arch/x86_64/types/mod.rs

@@ -0,0 +1,13 @@
+mod arg;
+mod asm;
+mod imm;
+mod mem;
+mod reg;
+mod width;
+
+pub use arg::*;
+pub use asm::*;
+pub use imm::*;
+pub use mem::*;
+pub use reg::*;
+pub use width::*;

src/arch/x86_64/types/reg.rs

@@ -0,0 +1,196 @@
+use super::Width;
+
+#[derive(Clone, Copy, PartialEq)]
+pub struct RegW {
+    reg: Reg,
+    high: bool,
+    width: Width,
+}
+
+pub type Reg = u8;
+
+def_regs! { RegW;
+    0b0000 : rax eax ax al,
+    0b0001 : rcx ecx cx cl !_,
+    0b0010 : rdx edx dx dl,
+    0b0011 : rbx ebx bx bl,
+
+    0b0100 : rsp esp sp spl norex=ah !_,
+    0b0101 : rbp ebp bp bpl norex=ch !_,
+    0b0110 : rsi esi si sil norex=dh !_,
+    0b0111 : rdi edi di dil norex=bh,
+
+    0b1000 : r8  r8d  r8w  r8b,
+    0b1001 : r9  r9d  r9w  r9b !_,
+    0b1010 : r10 r10d r10w r10b,
+    0b1011 : r11 r11d r11w r11b,
+    0b1100 : r12 r12d r12w r12b !_,
+    0b1101 : r13 r13d r13w r13b,
+    0b1110 : r14 r14d r14w r14b,
+    0b1111 : r15 r15d r15w r15b,
+}
+
+impl RegW {
+    pub fn reg(&self) -> u8 {
+        self.reg
+    }
+
+    pub fn base(&self) -> u8 {
+        self.reg & 0b111
+    }
+    /// checks if register is not one of the first 8 (0-7)
+    pub fn gt8(&self) -> bool {
+        self.reg >= 0b1000
+    }
+    pub fn gt4(&self) -> bool {
+        self.reg >= 0b0100
+    }
+
+    pub fn width(&self) -> Width {
+        self.width
+    }
+
+    pub fn not8(&self) -> u8 {
+        self.width.not8()
+    }
+
+    pub fn high(&self) -> bool {
+        self.high
+    }
+
+    /// if self has 64 bit width, changes width to 32 bit
+    pub fn lower64(&self) -> Self {
+        let mut new = *self;
+        new.width = new.width.min(Width::B32);
+        new
+    }
+
+    pub fn requires_rex(&self) -> bool {
+        self.gt8()
+            || self.width == Width::B64
+            || (self.gt4() && self.width == Width::B8 && !self.high)
+    }
+
+    pub fn incompatible(&self, other: &RegW) -> bool {
+        (self.requires_rex() && other.high) || (self.high && other.requires_rex())
+    }
+
+    const fn new(reg: u8, width: Width, high: bool) -> Self {
+        Self { reg, high, width }
+    }
+}
+
+impl Width {
+    pub const fn max_val(&self) -> u64 {
+        match self {
+            Self::B64 => u64::MAX,
+            Self::B32 => u32::MAX as u64,
+            Self::B16 => u16::MAX as u64,
+            Self::B8 { .. } => u8::MAX as u64,
+        }
+    }
+
+    pub fn min(self, other: Self) -> Self {
+        if self <= other { self } else { other }
+    }
+
+    pub const fn bytes(&self) -> usize {
+        match self {
+            Self::B64 => 8,
+            Self::B32 => 4,
+            Self::B16 => 2,
+            Self::B8 { .. } => 1,
+        }
+    }
+
+    /// greater than 8 bits
+    pub const fn not8(&self) -> u8 {
+        !matches!(self, Self::B8) as u8
+    }
+}
+
+macro_rules! filter {
+    ($($filtered:ident)*; ! $_:tt $($item:ident)*; $($rest:tt)*) => {
+        filter!($($filtered)* $($item)*; $($rest)*)
+    };
+    ($($filtered:ident)*; $($item:ident)*; $($rest:tt)*) => {
+        filter!($($filtered)*; $($rest)*)
+    };
+    ($($filtered:ident)*;) => {
+        [$($filtered, )*]
+    };
+}
+use filter;
+
+macro_rules! def_regs {
+    ($reg:ident; $($val:literal : $B64:ident $B32:ident $B16:ident $B8:ident $(norex=$B8H:ident)? $(!$imp:tt)?,)*) => {
+        pub mod regs {
+            $(
+            #[allow(non_upper_case_globals)]
+            pub const $B64: u8 = $val;
+            )*
+        }
+        pub mod regws {
+            use super::*;
+            $(
+            #[allow(non_upper_case_globals)]
+            pub const $B64: $reg = $reg::new($val, Width::B64, false);
+            #[allow(non_upper_case_globals)]
+            pub const $B32: $reg = $reg::new($val, Width::B32, false);
+            #[allow(non_upper_case_globals)]
+            pub const $B16: $reg = $reg::new($val, Width::B16, false);
+            #[allow(non_upper_case_globals)]
+            pub const $B8 : $reg = $reg::new($val, Width::B8 , false);
+            $(
+            #[allow(non_upper_case_globals)]
+            pub const $B8H: $reg = $reg::new($val, Width::B8, true);
+            )?
+            )*
+
+            impl $reg {
+                // #[cfg(test)]
+                // pub const ALL: &[$reg] = &[
+                //     $( $B64, $B32, $B16, $B8, $($B8H,)? )*
+                // ];
+
+                #[cfg(test)]
+                pub const IMPORTANT: &[$reg] = &
+                    filter!(; $($(!$imp)? $B64 $B32 $B16 $B8 $($B8H)?; )* )
+                ;
+
+                pub fn parse(s: &str) -> Option<Self> {
+                    Some(match s.to_lowercase().as_str() {
+                        $(
+                        stringify!($B64) => $B64,
+                        stringify!($B32) => $B32,
+                        stringify!($B16) => $B16,
+                        stringify!($B8 ) => $B8,
+                        $(
+                        stringify!($B8H) => $B8H,
+                        )?
+                        )*
+                        _ => return None,
+                    })
+                }
+            }
+            impl std::fmt::Display for $reg {
+                #[allow(non_upper_case_globals)]
+                fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+                    write!(f, "{}", match *self {
+                        $(
+                        $B64 => stringify!($B64),
+                        $B32 => stringify!($B32),
+                        $B16 => stringify!($B16),
+                        $B8  => stringify!($B8),
+                        $(
+                        $B8H => stringify!($B8H),
+                        )?
+                        )*
+                        _ => "UNKNOWN",
+                    })
+                }
+            }
+        }
+    };
+}
+use def_regs;

src/arch/x86_64/types/width.rs

@@ -0,0 +1,22 @@
+use super::*;
+
+#[derive(Debug, Clone, Copy, PartialEq, PartialOrd)]
+#[repr(u8)]
+pub enum Width {
+    B8 = 0,
+    B16 = 1,
+    B32 = 2,
+    B64 = 3,
+}
+
+impl From<RegW> for Width {
+    fn from(value: RegW) -> Self {
+        value.width()
+    }
+}
+
+impl From<Mem> for Width {
+    fn from(value: Mem) -> Self {
+        value.width
+    }
+}

src/arch/x86_64/util.rs

@@ -1,152 +1,3 @@
-use crate::backend::Symbol;
-
-use super::*;
-
-pub trait ModRMRM {
-    fn rm(&self) -> u8;
-    fn addr(&self) -> EffAddr;
-}
-
-pub enum EffAddr {
-    Mem0,
-    Mem8(i8),
-    Mem32(i32),
-    Sym(Symbol),
-    None,
-}
-
-impl ModRMRM for Reg {
-    fn rm(&self) -> u8 {
-        self.base()
-    }
-    fn addr(&self) -> EffAddr {
-        EffAddr::None
-    }
-}
-
-impl ModRMRM for Mem {
-    fn rm(&self) -> u8 {
-        self.reg.base()
-    }
-    fn addr(&self) -> EffAddr {
-        const I8_MIN: i32 = i8::MIN as i32;
-        const I8_MAX: i32 = i8::MAX as i32;
-        let disp = self.disp;
-        match disp {
-            0 => {
-                if self.reg.base() == 0b101 {
-                    EffAddr::Mem8(0)
-                } else {
-                    EffAddr::Mem0
-                }
-            }
-            I8_MIN..=I8_MAX => EffAddr::Mem8(disp as i8),
-            _ => EffAddr::Mem32(disp),
-        }
-    }
-}
-
-impl ModRMRM for i32 {
-    fn rm(&self) -> u8 {
-        0b101
-    }
-    fn addr(&self) -> EffAddr {
-        EffAddr::Mem32(*self)
-    }
-}
-
-impl ModRMRM for Symbol {
-    fn rm(&self) -> u8 {
-        0b101
-    }
-
-    fn addr(&self) -> EffAddr {
-        EffAddr::Sym(*self)
-    }
-}
-
-impl ModRMReg for u8 {
-    fn val(&self) -> u8 {
-        *self
-    }
-}
-
-impl ModRMReg for Reg {
-    fn val(&self) -> u8 {
-        self.base()
-    }
-}
-
-pub trait ModRMReg {
-    fn val(&self) -> u8;
-}
-
-#[inline(always)]
-pub fn rex(w: impl RexW, r: impl RexBit, x: u8, b: impl RexBit) -> u8 {
-    0b0100_0000 | bit(w.rexw(), 3) | bit(r.rex(), 2) | bit(x.rex(), 1) | bit(b.rex(), 0)
-}
-
-#[inline(always)]
-fn bit(val: bool, pos: u8) -> u8 {
-    (val as u8) << pos
-}
-
-pub trait RexBit: Sized {
-    fn rex(&self) -> bool;
-    fn req(&self) -> bool {
-        false
-    }
-}
-
-impl RexBit for u8 {
-    fn rex(&self) -> bool {
-        *self != 0
-    }
-}
-
-impl RexBit for Reg {
-    fn rex(&self) -> bool {
-        self.gt8()
-    }
-    fn req(&self) -> bool {
-        self.gt4() && (self.width() == Width::B8) && !self.high()
-    }
-}
-
-impl RexBit for Mem {
-    fn rex(&self) -> bool {
-        self.reg.rex()
-    }
-}
-
-pub trait RexW {
-    fn rexw(&self) -> bool;
-}
-
-impl RexW for Width {
-    fn rexw(&self) -> bool {
-        *self == Width::B64
-    }
-}
-
-impl RexW for Reg {
-    fn rexw(&self) -> bool {
-        self.width().rexw()
-    }
-}
-
-impl RexW for u8 {
-    fn rexw(&self) -> bool {
-        *self == 1
-    }
-}
-
-impl RexW for Mem {
-    fn rexw(&self) -> bool {
-        self.width.rexw()
-    }
-}
-
 /// assumes the next instruction is directly after
 pub fn addr_offset(pos: usize, addr: u64) -> [u8; 4] {
     let pos = (pos + 4) as i32;

src/backend/ir/id.rs

@@ -0,0 +1,31 @@
+ids!(VarId FnId);
+
+impl<A: Arch> Index<FnId> for Vec<Func<A>> {
+    type Output = Func<A>;
+
+    fn index(&self, index: FnId) -> &Self::Output {
+        &self[index.0]
+    }
+}
+
+impl<A: Arch> Index<&FnId> for Vec<Func<A>> {
+    type Output = Func<A>;
+
+    fn index(&self, index: &FnId) -> &Self::Output {
+        &self[index.0]
+    }
+}
+
+macro_rules! ids {
+    ($($name:ident)*) => {
+        $(
+        #[derive(Clone, Copy, PartialEq, Eq, Hash)]
+        pub struct $name(usize);
+        )*
+    };
+}
+use std::ops::Index;
+
+use ids;
+
+use crate::{arch::Arch, backend::Func};

src/backend/ir/mod.rs

@@ -1,6 +1,8 @@
 mod addr;
+mod id;
 mod symbol;
 pub use addr::*;
+pub use id::*;
 pub use symbol::*;
 
 use crate::{arch::Arch, backend::LinkedProgram, io::CompilerMsg};
@@ -10,6 +12,7 @@ pub struct Program<A: Arch> {
     pub funcs: Vec<Func<A>>,
     pub entry: Option<Symbol>,
     pub external: Vec<External>,
+    pub call_convs: Vec<A::CallConv>,
 
     sym_info: Vec<SymInfo>,
     sym_count: usize,
@@ -21,8 +24,10 @@ pub struct Data {
 }
 
 pub struct Func<A: Arch> {
-    pub instrs: Vec<Instr<A>>,
+    pub params: Vec<VarId>,
+    pub body: Body<A>,
     pub sym: Symbol,
+    pub conv: usize,
 }
 
 pub struct External {
@@ -35,16 +40,38 @@ pub struct SymInfo {
     pub external: bool,
 }
 
+pub type Body<A> = Vec<Instr<A>>;
+
 pub enum Instr<A: Arch> {
-    Set { dst: VarId, src: Vec<u8> },
-    Call { dst: FnId, args: Vec<VarId> },
-    Copy { dst: VarId, src: VarId },
+    Set {
+        dst: VarId,
+        src: Vec<u8>,
+    },
+    Call {
+        dst: VarId,
+        f: FnId,
+        args: Vec<VarId>,
+    },
+    Copy {
+        dst: VarId,
+        src: VarId,
+    },
+    Add {
+        dst: VarId,
+        src1: VarId,
+        src2: VarId,
+    },
+    If {
+        cond: VarId,
+        then: Body<A>,
+        else_: Body<A>,
+    },
+    Loop(Body<A>),
+    Return(Option<VarId>),
+    Break(Option<VarId>),
     Asm(A::Asm),
 }
 
-pub type VarId = usize;
-pub type FnId = usize;
-
 impl<A: Arch> Program<A> {
     pub fn encode_data(&self, data: &mut Vec<u8>, sym_tab: &mut SymTable<A::Addr>) {
         for d in &self.ro_data {
@@ -70,7 +97,7 @@ impl<A: Arch> Program<A> {
             name: name.into(),
             external: false,
         });
-        self.funcs.push(Func { instrs, sym });
+        self.funcs.push(Func { body: instrs, sym });
         sym
     }
 

src/parser/nodes/asm/x86_64.rs

@@ -64,21 +64,21 @@ pub fn parse_imm(mut s: &str, span: Span) -> Result<Imm, CompilerMsg> {
     Ok(Imm(val))
 }
 
-pub fn parse_rmi(ctx: &mut crate::parser::ParseCtx) -> Result<RegImmMem, CompilerMsg> {
+pub fn parse_rmi(ctx: &mut crate::parser::ParseCtx) -> Result<RegMemImm, CompilerMsg> {
     let next = ctx.expect_next()?;
     let err = || CompilerMsg::unexpected_token(&next, ctx.span, "a register or immediate");
     Ok(match &next {
-        Token::Ident(ident) => RegImmMem::Reg(Reg::parse(ident).ok_or_else(err)?),
-        Token::Lit(LitTy::Number(num)) => RegImmMem::Imm(parse_imm(num, ctx.span)?),
+        Token::Ident(ident) => RegMemImm::Reg(RegW::parse(ident).ok_or_else(err)?),
+        Token::Lit(LitTy::Number(num)) => RegMemImm::Imm(parse_imm(num, ctx.span)?),
         _ => return Err(err()),
     })
 }
 
-pub fn parse_reg(ctx: &mut crate::parser::ParseCtx) -> Result<Reg, CompilerMsg> {
+pub fn parse_reg(ctx: &mut crate::parser::ParseCtx) -> Result<RegW, CompilerMsg> {
     let next = ctx.expect_next()?;
     let err = || CompilerMsg::unexpected_token(&next, ctx.span, "a register");
     let Token::Ident(next) = &next else {
         return Err(err());
     };
-    Reg::parse(next).ok_or_else(err)
+    RegW::parse(next).ok_or_else(err)
 }