brooke/reliant
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

tweaks

Browse source
This commit is contained in:
Brooke Vibber 2025-12-29 15:33:58 -08:00
commit 339dbf0c23
1 changed files with 126 additions and 12 deletions
Download patch file Download diff file Expand all files Collapse all files

138
src/main.rs
View file

@ -108,8 +108,7 @@ impl MachineState {
return Self::new_with_state(memory, pages);
}
fn get_page_table_entry(&mut self, address: usize) -> PageTableEntry {
let page = address >> PAGE_BITS;
fn get_page_table_entry(&self, page: usize) -> PageTableEntry {
if page < self.pages.len() {
return self.pages[page];
} else {
@ -117,38 +116,37 @@ impl MachineState {
}
}
fn set_page_table_entry(&mut self, address: usize, entry: PageTableEntry) {
let page = address >> PAGE_BITS;
fn set_page_table_entry(&mut self, page: usize, entry: PageTableEntry) {
if page < self.pages.len() {
self.pages[address >> 12] = entry;
self.pages[page] = entry;
} else {
panic!("@fixme: handle attempts to expand address space");
}
}
fn lb_physical(&mut self, address: usize) -> i64 {
fn lb_physical(&self, address: usize) -> i64 {
return self.memory[address] as i8 as i64;
}
fn lbu_physical(&mut self, address: usize) -> i64 {
fn lbu_physical(&self, address: usize) -> i64 {
return self.memory[address] as u8 as i64;
}
fn lh_physical(&mut self, address: usize) -> i64 {
fn lh_physical(&self, address: usize) -> i64 {
return (
(self.memory[address ] as u16) |
((self.memory[address + 1] as u16) << 8)
) as i16 as i64;
}
fn lhu_physical(&mut self, address: usize) -> i64 {
fn lhu_physical(&self, address: usize) -> i64 {
return (
(self.memory[address ] as u16) |
((self.memory[address + 1] as u16) << 8)
) as i64;
}
fn lw_physical(&mut self, address: usize) -> i64 {
fn lw_physical(&self, address: usize) -> i64 {
return (
(self.memory[address ] as u32) |
((self.memory[address + 1] as u32) << 8) |
@ -157,7 +155,7 @@ impl MachineState {
) as i32 as i64;
}
fn lwu_physical(&mut self, address: usize) -> i64 {
fn lwu_physical(&self, address: usize) -> i64 {
return (
(self.memory[address ] as u32) |
((self.memory[address + 1] as u32) << 8) |
@ -166,7 +164,7 @@ impl MachineState {
) as u32 as i64;
}
fn ld_physical(&mut self, address: usize) -> i64 {
fn ld_physical(&self, address: usize) -> i64 {
return (
(self.memory[address ] as u64) |
((self.memory[address + 1] as u64) << 8) |
@ -270,6 +268,122 @@ impl CoreState {
dirty: vec![0u8; machine.memory.len()]
}
}
fn lb(&self, machine: &MachineState, address: i64) -> i64 {
let raw_page = (address as u64) >> PAGE_BITS;
if raw_page < machine.pages.len() as u64 {
let addr = address as usize;
let page = raw_page as usize;
let entry = machine.get_page_table_entry(page);
if entry.is_readable() {
return machine.lb_physical(address as usize);
}
}
panic!("@fixme: trap on read failure on page");
}
fn lbu(&self, machine: &MachineState, address: i64) -> i64 {
let raw_page = (address as u64) >> PAGE_BITS;
if raw_page < machine.pages.len() as u64 {
let addr = address as usize;
let page = raw_page as usize;
let entry = machine.get_page_table_entry(page);
if entry.is_readable() {
return machine.lbu_physical(addr);
}
}
panic!("@fixme: trap on read failure on page");
}
fn lh(&self, machine: &MachineState, address: i64) -> i64 {
let raw_page = (address as u64) >> PAGE_BITS;
if raw_page < machine.pages.len() as u64 {
let addr = address as usize;
let page = raw_page as usize;
let entry = machine.get_page_table_entry(page);
if entry.is_readable() {
let offset = addr & (PAGE_SIZE - 1);
if offset < (PAGE_SIZE - 2) || machine.get_page_table_entry(page + 1).is_readable() {
return machine.lh_physical(addr);
} else {
panic!("@fixme: trap on read failure on page + 1");
}
}
}
panic!("@fixme: trap on read failure on page");
}
fn lhu(&self, machine: &MachineState, address: i64) -> i64 {
let raw_page = (address as u64) >> PAGE_BITS;
if raw_page < machine.pages.len() as u64 {
let addr = address as usize;
let page = raw_page as usize;
let entry = machine.get_page_table_entry(page);
if entry.is_readable() {
let offset = addr & (PAGE_SIZE - 1);
if offset < (PAGE_SIZE - 2) || machine.get_page_table_entry(page + 1).is_readable() {
return machine.lhu_physical(addr);
} else {
panic!("@fixme: trap on read failure on page + 1");
}
}
}
panic!("@fixme: trap on read failure on page");
}
fn lw(&self, machine: &MachineState, address: i64) -> i64 {
let raw_page = (address as u64) >> PAGE_BITS;
if raw_page < machine.pages.len() as u64 {
let addr = address as usize;
let page = raw_page as usize;
let entry = machine.get_page_table_entry(page);
if entry.is_readable() {
let offset = addr & (PAGE_SIZE - 1);
if offset < (PAGE_SIZE - 4) || machine.get_page_table_entry(page + 1).is_readable() {
return machine.lw_physical(addr);
} else {
panic!("@fixme: trap on read failure on page + 1");
}
}
}
panic!("@fixme: trap on read failure on page");
}
fn lwu(&self, machine: &MachineState, address: i64) -> i64 {
let raw_page = (address as u64) >> PAGE_BITS;
if raw_page < machine.pages.len() as u64 {
let addr = address as usize;
let page = raw_page as usize;
let entry = machine.get_page_table_entry(page);
if entry.is_readable() {
let offset = addr & (PAGE_SIZE - 1);
if offset < (PAGE_SIZE - 4) || machine.get_page_table_entry(page + 1).is_readable() {
return machine.lwu_physical(addr);
} else {
panic!("@fixme: trap on read failure on page + 1");
}
}
}
panic!("@fixme: trap on read failure on page");
}
fn ld(&self, machine: &MachineState, address: i64) -> i64 {
let raw_page = (address as u64) >> PAGE_BITS;
if raw_page < machine.pages.len() as u64 {
let addr = address as usize;
let page = raw_page as usize;
let entry = machine.get_page_table_entry(page);
if entry.is_readable() {
let offset = addr & (PAGE_SIZE - 1);
if offset < (PAGE_SIZE - 8) || machine.get_page_table_entry(page + 1).is_readable() {
return machine.ld_physical(addr);
} else {
panic!("@fixme: trap on read failure on page + 1");
}
}
}
panic!("@fixme: trap on read failure on page");
}
}