missing symbol filling

src/compiler/elf.rs

@@ -1,3 +1,5 @@
+use super::program::Addr;
+
 #[repr(C)]
 pub struct ELF64Header {
     magic: u32,
@@ -49,7 +51,7 @@ pub struct SectionHeader {
 }
 
 // this is currently specialized for riscv64; obviously add params later
-pub fn create(program: Vec<u8>, start_offset: u64) -> Vec<u8> {
+pub fn create(program: Vec<u8>, start_offset: Addr) -> Vec<u8> {
     let addr_start = 0x1000;
     let page_size = 0x1000;
     let progam_size = std::mem::size_of_val(&program[..]) as u64;
@@ -76,7 +78,7 @@ pub fn create(program: Vec<u8>, start_offset: u64) -> Vec<u8> {
         ty: 0x2,       // executable
         machine: 0xf3, // risc-v
         e_version: 0x1,
-        entry: addr_start + program_pos + start_offset,
+        entry: addr_start + program_pos + start_offset.val(),
         program_header_offset: size_of::<ELF64Header>() as u64,
         section_header_offset: 0x0,
         // C ABI (16 bit instruction align) + double precision floats

src/compiler/mod.rs

@@ -10,6 +10,8 @@ mod program;
 mod riscv64;
 mod target;
 
+use program::*;
+
 pub fn main() {
     use std::io::prelude::*;
     let dir = Path::new("./build");
@@ -62,7 +64,3 @@ pub fn main() {
     }
 }
 
-//     qemu-riscv64 -g 1234 test &
-//     riscv64-linux-gnu-gdb -q \
-//         -ex "target remote :1234" \
-//         test

src/compiler/program.rs

@@ -1,35 +1,118 @@
-use std::collections::HashMap;
+use std::{collections::HashMap, ops::Deref};
 
-pub fn create_program<I: Instr>(
+pub fn create_program<I: Instr>(map: SymMap<I>, start: Symbol) -> (Vec<u8>, Option<Addr>) {
-    ro_data: HashMap<String, Vec<u8>>,
-    functions: Vec<Function<I>>,
-) -> (Vec<u8>, Option<u64>) {
     let mut data = Vec::new();
-    let mut sym_map = HashMap::new();
+    let mut sym_table = SymTable::new(map.len());
-    for (key, val) in ro_data {
+    let mut missing = HashMap::<Symbol, Vec<(Addr, I)>>::new();
-        sym_map.insert(key, data.len() as u64);
+    for (val, id) in map.ro_data {
+        sym_table.insert(id, Addr(data.len() as u64));
         data.extend(val);
     }
-    let mut start = None;
+    for (fun, id) in map.functions {
-    for fun in functions {
+        sym_table.insert(id, Addr(data.len() as u64));
-        if fun.label == "_start" {
+        for i in fun {
-            start = Some(data.len() as u64);
+            let i_pos = Addr(data.len() as u64);
-        }
+            if let Some(sym) = i.push(&mut data, &sym_table, i_pos, false) {
-        sym_map.insert(fun.label, data.len() as u64);
+                if let Some(vec) = missing.get_mut(&sym) {
-        for i in fun.instructions {
+                    vec.push((i_pos, i));
-            let pos = data.len() as u64;
+                } else {
-            i.push(&mut data, &sym_map, pos);
+                    missing.insert(sym, vec![(i_pos, i)]);
                 }
             }
-    (data, start)
+        }
-}
+        if let Some(vec) = missing.remove(&id) {
-
+            for (addr, i) in vec {
-pub struct Function<I: Instr> {
+                let mut replace = Vec::new();
-    pub label: String,
+                i.push(&mut replace, &sym_table, addr, true);
-    pub instructions: Vec<I>,
+                let pos = addr.val() as usize;
+                data[pos..pos + replace.len()].copy_from_slice(&replace);
+            }
+        }
+    }
+    assert!(missing.is_empty());
+    (data, sym_table.get(start))
 }
 
 pub trait Instr {
-    fn push(&self, data: &mut Vec<u8>, ro_map: &HashMap<String, u64>, pos: u64) -> Option<String>;
+    fn push(&self, data: &mut Vec<u8>, syms: &SymTable, pos: Addr, missing: bool) -> Option<Symbol>;
 }
 
+#[derive(Debug, Clone, Copy, PartialEq)]
+pub struct Addr(u64);
+impl Addr {
+    const NONE: Self = Self(!0);
+    pub fn val(&self) -> u64 {
+        self.0
+    }
+}
+
+#[derive(Debug, Clone, Copy, Hash, PartialEq, Eq)]
+pub struct Symbol(usize);
+/// intentionally does not have copy or clone;
+/// this should only be consumed once
+pub struct WritableSymbol(Symbol);
+
+impl Deref for WritableSymbol {
+    type Target = Symbol;
+    fn deref(&self) -> &Self::Target {
+        &self.0
+    }
+}
+
+pub struct SymMap<I: Instr> {
+    i: usize,
+    ro_data: Vec<(Vec<u8>, Symbol)>,
+    functions: Vec<(Vec<I>, Symbol)>,
+}
+
+impl<I: Instr> SymMap<I> {
+    pub fn new() -> Self {
+        Self {
+            i: 0,
+            ro_data: Vec::new(),
+            functions: Vec::new(),
+        }
+    }
+    pub fn push_ro_data(&mut self, data: impl Into<Vec<u8>>) -> (Symbol, usize) {
+        let sym = self.reserve();
+        self.write_ro_data(sym, data)
+    }
+    pub fn push_fn(&mut self, instructions: Vec<I>) -> Symbol {
+        let sym = self.reserve();
+        self.write_fn(sym, instructions)
+    }
+    pub fn write_ro_data(&mut self, sym: WritableSymbol, data: impl Into<Vec<u8>>) -> (Symbol, usize) {
+        let data = data.into();
+        let len = data.len();
+        self.ro_data.push((data, *sym));
+        (*sym, len)
+    }
+    pub fn write_fn(&mut self, sym: WritableSymbol, instructions: Vec<I>) -> Symbol {
+        self.functions.push((instructions, *sym));
+        *sym
+    }
+    pub fn reserve(&mut self) -> WritableSymbol {
+        let val = self.i;
+        self.i += 1;
+        WritableSymbol(Symbol(val))
+    }
+    pub fn len(&self) -> usize {
+        self.functions.len() + self.ro_data.len()
+    }
+}
+
+pub struct SymTable(Vec<Addr>);
+impl SymTable {
+    pub fn new(len: usize) -> Self {
+        Self(vec![Addr::NONE; len])
+    }
+    pub fn insert(&mut self, sym: Symbol, addr: Addr) {
+        self.0[sym.0] = addr;
+    }
+    pub fn get(&self, sym: Symbol) -> Option<Addr> {
+        match self.0[sym.0] {
+            Addr::NONE => None,
+            addr => Some(addr),
+        }
+    }
+}

src/compiler/riscv64/asm.rs

@@ -1,57 +1,56 @@
-use crate::compiler::program::Instr;
+use crate::compiler::program::{Addr, Instr, SymTable, Symbol};
 
 use super::*;
 
 pub enum AsmInstruction {
     Addi(Reg, Reg, i32),
-    La(Reg, String),
+    La(Reg, Symbol),
     Jal(Reg, i32),
-    Jala(String),
+    Call(Symbol),
-    Ja(String),
+    J(Symbol),
     Ret,
     Ecall,
+    Li(Reg, i32),
 }
 
 impl Instr for AsmInstruction {
-    fn push(
+    fn push(&self, data: &mut Vec<u8>, sym_map: &SymTable, pos: Addr, missing: bool) -> Option<Symbol> {
-        &self,
+        let last = match self {
-        data: &mut Vec<u8>,
+            Self::Addi(dest, src, imm) => addi(*dest, *src, BitsI32::new(*imm)),
-        sym_map: &std::collections::HashMap<String, u64>,
-        pos: u64,
-    ) -> Option<String> {
-        match self {
-            Self::Addi(dest, src, imm) => {
-                data.extend(addi(*dest, *src, BitsI32::new(*imm)).to_le_bytes());
-            }
             Self::La(dest, sym) => {
-                if let Some(addr) = sym_map.get(sym) {
+                if let Some(addr) = sym_map.get(*sym) {
-                    let offset = *addr as i32 - pos as i32;
+                    let offset = addr.val() as i32 - pos.val() as i32;
                     data.extend(auipc(*dest, BitsI32::new(0)).to_le_bytes());
-                    data.extend(addi(*dest, *dest, BitsI32::new(offset)).to_le_bytes());
+                    addi(*dest, *dest, BitsI32::new(offset))
                 } else {
-                    return Some(sym.to_string());
+                    data.extend_from_slice(&[0; 2 * 4]);
+                    return Some(*sym);
                 }
             }
-            Self::Jal(dest, offset) => data.extend(jal(*dest, BitsI32::new(*offset)).to_le_bytes()),
+            Self::Jal(dest, offset) => jal(*dest, BitsI32::new(*offset)),
-            Self::Ja(sym) => {
+            Self::J(sym) => {
-                if let Some(addr) = sym_map.get(sym) {
+                if let Some(addr) = sym_map.get(*sym) {
-                    let offset = *addr as i32 - pos as i32;
+                    let offset = addr.val() as i32 - pos.val() as i32;
-                    data.extend(j(BitsI32::new(offset)).to_le_bytes());
+                    j(BitsI32::new(offset))
                 } else {
-                    return Some(sym.to_string());
+                    data.extend_from_slice(&[0; 4]);
+                    return Some(*sym);
                 }
             }
-            Self::Jala(sym) => {
+            Self::Call(sym) => {
-                if let Some(addr) = sym_map.get(sym) {
+                if let Some(addr) = sym_map.get(*sym) {
-                    let offset = *addr as i32 - pos as i32;
+                    let offset = addr.val() as i32 - pos.val() as i32;
-                    data.extend(jal(ra, BitsI32::new(offset)).to_le_bytes());
+                    jal(ra, BitsI32::new(offset))
                 } else {
-                    return Some(sym.to_string());
+                    data.extend_from_slice(&[0; 4]);
+                    return Some(*sym);
                 }
             }
-            Self::Ret => data.extend(ret().to_le_bytes()),
+            Self::Ret => ret(),
-            Self::Ecall => data.extend(ecall().to_le_bytes()),
+            Self::Ecall => ecall(),
-        }
+            Self::Li(reg, val) => addi(*reg, zero, BitsI32::new(*val)),
+        };
+        data.extend(last.to_le_bytes());
         None
     }
 }

src/compiler/riscv64/mod.rs

@@ -5,9 +5,7 @@ mod opcode;
 mod reg;
 mod single;
 
-use std::collections::HashMap;
+use super::{create_program, elf, SymMap};
-
-use super::{elf, program::{create_program, Function}};
 use crate::util::BitsI32;
 use base::*;
 use funct::{op::*, width};
@@ -18,64 +16,33 @@ use single::*;
 
 pub fn gen() -> Vec<u8> {
     use asm::AsmInstruction as I;
-    // let mut program = Vec::new();
+    let mut table = SymMap::new();
-    // let msg = b"Hello world!\n";
+    let (msg, len) = table.push_ro_data(b"Hello world!\n");
-    // program.extend(msg);
+    let (msg2, len2) = table.push_ro_data(b"IT WORKS!!!!\n");
-    // program.resize(((program.len() - 1) / 4 + 1) * 4, 0);
+    let print_stuff = table.reserve();
-    // let start = program.len() as u64;
+    let start = table.push_fn(vec![
-    // let instructions = [
+        I::Call(*print_stuff),
-    //     auipc(t0, BitsI32::new(0)),
+        I::Li(a0, 0),
-    //     addi(t0, t0, BitsI32::new(-(start as i32))),
+        I::Li(a7, 93),
-    //     addi(a0, zero, BitsI32::new(1)),
-    //     mv(a1, t0),
-    //     addi(a2, zero, BitsI32::new(msg.len() as i32)),
-    //     addi(a7, zero, BitsI32::new(64)),
-    //     addi(t0, zero, const { BitsI32::new(-10) }),
-    //     ecall(),
-    //     // exit
-    //     addi(a0, zero, BitsI32::new(0)),
-    //     addi(a7, zero, BitsI32::new(93)),
-    //     ecall(),
-    //     j(BitsI32::new(0)),
-    // ];
-    // for i in instructions {
-    //     program.extend(i.to_le_bytes());
-    // }
-    let msg = b"Hello world!\n";
-    let msg2 = b"IT WORKS!!!!\n";
-    let ro_data = HashMap::from([
-        ("msg".to_string(), msg.to_vec()),
-        ("msg2".to_string(), msg2.to_vec()),
-    ]);
-    let functions = vec![
-        Function {
-            label: "print_stuff".to_string(),
-            instructions: vec![
-                I::Addi(a0, zero, 1),
-                I::La(a1, "msg".to_string()),
-                I::Addi(a2, zero, msg.len() as i32),
-                I::Addi(a7, zero, 64),
-                I::Ecall,
-                I::Addi(a0, zero, 1),
-                I::La(a1, "msg2".to_string()),
-                I::Addi(a2, zero, msg2.len() as i32),
-                I::Addi(a7, zero, 64),
-                I::Ecall,
-                I::Ret,
-            ]
-        },
-        Function {
-            label: "_start".to_string(),
-            instructions: vec![
-                I::Jala("print_stuff".to_string()),
-                I::Ecall,
-                I::Addi(a0, zero, 0),
-                I::Addi(a7, zero, 93),
         I::Ecall,
         I::Jal(zero, 0),
-            ]
+    ]);
-        },
+    table.write_fn(
-    ];
+        print_stuff,
-    let (program, start) = create_program(ro_data, functions);
+        vec![
+            I::Li(a0, 1),
+            I::La(a1, msg),
+            I::Li(a2, len as i32),
+            I::Li(a7, 64),
+            I::Ecall,
+            I::Li(a0, 1),
+            I::La(a1, msg2),
+            I::Li(a2, len2 as i32),
+            I::Li(a7, 64),
+            I::Ecall,
+            I::Ret,
+        ],
+    );
+    let (program, start) = create_program(table, start);
     elf::create(program, start.expect("no start!"))
 }

src/main.rs

@@ -1,6 +1,4 @@
 #![feature(box_patterns)]
-#![feature(const_unbounded_shifts)]
-#![feature(unbounded_shifts)]
 
 mod util;
 mod compiler;