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authorDavid Li <li.davidm96@gmail.com>2015-12-31 10:27:58 -0700
committerDavid Li <li.davidm96@gmail.com>2015-12-31 10:27:58 -0700
commit5a996639e405967131711daf24f8c324916e5d3a (patch)
treec71d3e2fdf2a030d3c6f8b82bd440eb35d4b018a /src
parentb0f627e9df022cedefee871bdaa64c8e06198a1c (diff)
Refactor Core.step slightly
Diffstat (limited to 'src')
-rw-r--r--src/simulator.rs444
1 files changed, 221 insertions, 223 deletions
diff --git a/src/simulator.rs b/src/simulator.rs
index be47764..27e543a 100644
--- a/src/simulator.rs
+++ b/src/simulator.rs
@@ -18,8 +18,7 @@ use std::cell::RefCell;
use std::rc::Rc;
use isa;
-use binary::{Binary};
-use memory::{MemoryInterface, Memory, MemoryError};
+use memory::{MemoryInterface, MemoryError};
struct RegisterFile {
registers: [isa::Word; 32],
@@ -76,260 +75,254 @@ impl RegisterFile {
}
impl<'a> Core<'a> {
+ // TODO: take Rc<RefCell<>> to Memory as well?
pub fn new(cache: Rc<RefCell<Box<MemoryInterface + 'a>>>) -> Core<'a> {
Core {
- pc: 0, // TODO: hardcoded: fix later
+ pc: 0x1002c, // TODO: hardcoded: fix later
registers: RegisterFile::new(),
running: true,
cache: cache,
}
}
- fn step(&mut self, inst: Option<isa::Instruction>) {
+ fn step(&mut self, inst: isa::Instruction) {
let pc = self.pc;
- if let Some(inst) = inst {
- match inst.opcode() {
- isa::opcodes::JALR => {
- // TODO: assert funct3 is 0
- let base = self.registers.read_word(inst.rs1())
- as isa::SignedWord;
- let target = (base + inst.i_imm()) as isa::Address;
- let retval = (pc + 4) as isa::Word;
- if target == 0x0 {
- // ret
- self.running = false;
- }
- else {
- self.registers.write_word(inst.rd(), retval);
- self.pc = target;
- return;
+ match inst.opcode() {
+ isa::opcodes::JALR => {
+ // TODO: assert funct3 is 0
+ let base = self.registers.read_word(inst.rs1())
+ as isa::SignedWord;
+ let target = (base + inst.i_imm()) as isa::Address;
+ let retval = (pc + 4) as isa::Word;
+ if target == 0x0 {
+ // ret
+ self.running = false;
+ }
+ else {
+ self.registers.write_word(inst.rd(), retval);
+ self.pc = target;
+ return;
+ }
+ },
+ isa::opcodes::JAL => {
+ let target = ((pc as isa::SignedWord) + inst.uj_imm()) as isa::Address;
+ self.registers.write_word(inst.rd(), (pc + 4) as isa::Word);
+ self.pc = target;
+ // panic!("JAL to {:X} 0x{:X}", pc, target);
+ return;
+ }
+ isa::opcodes::BRANCH => {
+ let target = ((pc as isa::SignedWord) + inst.sb_imm()) as isa::Address;
+ let rs1 = self.registers.read_word(inst.rs1());
+ let rs2 = self.registers.read_word(inst.rs2());
+ if match inst.funct3() {
+ isa::funct3::BEQ => rs1 == rs2,
+ isa::funct3::BNE => rs1 != rs2,
+ isa::funct3::BLT => (rs1 as isa::SignedWord) < (rs2 as isa::SignedWord),
+ isa::funct3::BGE => (rs1 as isa::SignedWord) > (rs2 as isa::SignedWord),
+ isa::funct3::BLTU => rs1 < rs2,
+ isa::funct3::BGEU => rs1 > rs2,
+ _ => {
+ self.trap(Trap::IllegalInstruction {
+ address: pc,
+ instruction: inst,
+ });
+ false
}
- },
- isa::opcodes::JAL => {
- let target = ((pc as isa::SignedWord) + inst.uj_imm()) as isa::Address;
- self.registers.write_word(inst.rd(), (pc + 4) as isa::Word);
+ } {
self.pc = target;
- // panic!("JAL to {:X} 0x{:X}", pc, target);
return;
}
- isa::opcodes::BRANCH => {
- let target = ((pc as isa::SignedWord) + inst.sb_imm()) as isa::Address;
- let rs1 = self.registers.read_word(inst.rs1());
- let rs2 = self.registers.read_word(inst.rs2());
- if match inst.funct3() {
- isa::funct3::BEQ => rs1 == rs2,
- isa::funct3::BNE => rs1 != rs2,
- isa::funct3::BLT => (rs1 as isa::SignedWord) < (rs2 as isa::SignedWord),
- isa::funct3::BGE => (rs1 as isa::SignedWord) > (rs2 as isa::SignedWord),
- isa::funct3::BLTU => rs1 < rs2,
- isa::funct3::BGEU => rs1 > rs2,
- _ => {
- self.trap(Trap::IllegalInstruction {
- address: pc,
- instruction: inst,
- });
- false
+ },
+ isa::opcodes::INTEGER_IMMEDIATE => {
+ let imm = inst.i_imm();
+ let src = self.registers.read_word(inst.rs1()) as isa::SignedWord;
+ if let Some(value) = match inst.funct3() {
+ isa::funct3::ADDI => {
+ Some(src.wrapping_add(imm) as isa::Word)
+ },
+ isa::funct3::SLLI => {
+ Some((src << inst.shamt()) as isa::Word)
+ },
+ isa::funct3::SLTI => {
+ if src < imm {
+ Some(1)
}
- } {
- self.pc = target;
- return;
- }
- },
- isa::opcodes::INTEGER_IMMEDIATE => {
- let imm = inst.i_imm();
- let src = self.registers.read_word(inst.rs1()) as isa::SignedWord;
- if let Some(value) = match inst.funct3() {
- isa::funct3::ADDI => {
- Some(src.wrapping_add(imm) as isa::Word)
- },
- isa::funct3::SLLI => {
- Some((src << inst.shamt()) as isa::Word)
- },
- isa::funct3::SLTI => {
- if src < imm {
- Some(1)
- }
- else {
- Some(0)
- }
- },
- isa::funct3::SLTIU => {
- if (src as isa::Word) < (imm as isa::Word) {
- Some(1)
- }
- else {
- Some(0)
- }
- },
- isa::funct3::XORI => {
- Some((src ^ imm) as isa::Word)
- },
- isa::funct3::SRLI_SRAI => {
- match inst.funct7() {
- isa::funct7::SRLI => Some(((src as isa::Word) >> inst.shamt()) as isa::Word),
- isa::funct7::SRAI => Some((src >> inst.shamt()) as isa::Word),
- _ => {
- self.trap(Trap::IllegalInstruction {
- address: pc,
- instruction: inst,
- });
- None
- }
+ else {
+ Some(0)
+ }
+ },
+ isa::funct3::SLTIU => {
+ if (src as isa::Word) < (imm as isa::Word) {
+ Some(1)
+ }
+ else {
+ Some(0)
+ }
+ },
+ isa::funct3::XORI => {
+ Some((src ^ imm) as isa::Word)
+ },
+ isa::funct3::SRLI_SRAI => {
+ match inst.funct7() {
+ isa::funct7::SRLI => Some(((src as isa::Word) >> inst.shamt()) as isa::Word),
+ isa::funct7::SRAI => Some((src >> inst.shamt()) as isa::Word),
+ _ => {
+ self.trap(Trap::IllegalInstruction {
+ address: pc,
+ instruction: inst,
+ });
+ None
}
- },
- isa::funct3::ORI => {
- Some((src | imm) as isa::Word)
- },
- isa::funct3::ANDI => {
- Some((src & imm) as isa::Word)
- },
- _ => {
- self.trap(Trap::IllegalInstruction {
- address: pc,
- instruction: inst,
- });
- None
}
- } {
- self.registers.write_word(inst.rd(), value);
+ },
+ isa::funct3::ORI => {
+ Some((src | imm) as isa::Word)
+ },
+ isa::funct3::ANDI => {
+ Some((src & imm) as isa::Word)
+ },
+ _ => {
+ self.trap(Trap::IllegalInstruction {
+ address: pc,
+ instruction: inst,
+ });
+ None
}
- },
- isa::opcodes::INTEGER_REGISTER => {
- let src1 = self.registers.read_word(inst.rs1());
- let src2 = self.registers.read_word(inst.rs2());
- let src2_shift = src2 & 0x1F;
- if let Some(value) = match inst.funct3() {
- isa::funct3::ADD_SUB => {
- match inst.funct7() {
- isa::funct7::ADD_SRL => Some(((src1 as isa::SignedWord).wrapping_add(src2 as isa::SignedWord)) as isa::Word),
- isa::funct7::SUB_SRA => Some(((src1 as isa::SignedWord).wrapping_sub(src2 as isa::SignedWord)) as isa::Word),
- _ => {
- self.trap(Trap::IllegalInstruction {
- address: pc,
- instruction: inst,
- });
- None
- }
- }
- },
- isa::funct3::SLL => {
- Some(src1 << src2_shift)
- },
- isa::funct3::SLT => {
- if (src1 as isa::SignedWord) < (src2 as isa::SignedWord) {
- Some(1)
- }
- else {
- Some(0)
- }
- },
- isa::funct3::SLTU => {
- if src1 < src2 {
- Some(1)
- }
- else {
- Some(0)
- }
- },
- isa::funct3::XOR => {
- Some(src1 ^ src2)
- },
- isa::funct3::SRL_SRA => {
- match inst.funct7() {
- isa::funct7::ADD_SRL => Some(src1 >> src2_shift),
- isa::funct7::SUB_SRA => Some(((src1 as isa::SignedWord) >> src2_shift) as isa::Word),
- _ => {
- self.trap(Trap::IllegalInstruction {
- address: pc,
- instruction: inst,
- });
- None
- }
+ } {
+ self.registers.write_word(inst.rd(), value);
+ }
+ },
+ isa::opcodes::INTEGER_REGISTER => {
+ let src1 = self.registers.read_word(inst.rs1());
+ let src2 = self.registers.read_word(inst.rs2());
+ let src2_shift = src2 & 0x1F;
+ if let Some(value) = match inst.funct3() {
+ isa::funct3::ADD_SUB => {
+ match inst.funct7() {
+ isa::funct7::ADD_SRL => Some(((src1 as isa::SignedWord).wrapping_add(src2 as isa::SignedWord)) as isa::Word),
+ isa::funct7::SUB_SRA => Some(((src1 as isa::SignedWord).wrapping_sub(src2 as isa::SignedWord)) as isa::Word),
+ _ => {
+ self.trap(Trap::IllegalInstruction {
+ address: pc,
+ instruction: inst,
+ });
+ None
}
- },
- isa::funct3::OR => {
- Some(src1 | src2)
- },
- isa::funct3::AND => {
- Some(src1 & src2)
- },
- _ => {
- self.trap(Trap::IllegalInstruction {
- address: pc,
- instruction: inst,
- });
- None
}
- } {
- self.registers.write_word(inst.rd(), value);
- }
- },
- isa::opcodes::LOAD => match inst.funct3() {
- isa::funct3::LW => {
- let imm = inst.i_imm();
- let base = self.registers.read_word(inst.rs1());
- let address = ((base as isa::SignedWord) + imm) as isa::Address;
- let result = self.cache.borrow_mut().read_word(address);
- match result {
- Ok(value) =>
- self.registers.write_word(inst.rd(), value),
- Err(MemoryError::CacheMiss {..}) => return,
- Err(MemoryError::InvalidAddress) => {
- self.trap(Trap::IllegalRead {
+ },
+ isa::funct3::SLL => {
+ Some(src1 << src2_shift)
+ },
+ isa::funct3::SLT => {
+ if (src1 as isa::SignedWord) < (src2 as isa::SignedWord) {
+ Some(1)
+ }
+ else {
+ Some(0)
+ }
+ },
+ isa::funct3::SLTU => {
+ if src1 < src2 {
+ Some(1)
+ }
+ else {
+ Some(0)
+ }
+ },
+ isa::funct3::XOR => {
+ Some(src1 ^ src2)
+ },
+ isa::funct3::SRL_SRA => {
+ match inst.funct7() {
+ isa::funct7::ADD_SRL => Some(src1 >> src2_shift),
+ isa::funct7::SUB_SRA => Some(((src1 as isa::SignedWord) >> src2_shift) as isa::Word),
+ _ => {
+ self.trap(Trap::IllegalInstruction {
address: pc,
instruction: inst,
- memory_address: address,
});
+ None
}
}
},
+ isa::funct3::OR => {
+ Some(src1 | src2)
+ },
+ isa::funct3::AND => {
+ Some(src1 & src2)
+ },
_ => {
- panic!("Invalid load funct3code: 0x{:x}", inst.funct3());
- }
- },
- isa::opcodes::STORE => match inst.funct3() {
- isa::funct3::SW => {
- let imm = inst.s_imm();
- let base = self.registers.read_word(inst.rs1());
- let val = self.registers.read_word(inst.rs2());
- let address = ((base as isa::SignedWord) + imm) as isa::Address;
- let result = self.cache.borrow_mut().write_word(address, val);
- match result {
- Ok(()) => (),
- Err(MemoryError::CacheMiss {..}) => return,
- Err(MemoryError::InvalidAddress) => {
- self.trap(Trap::IllegalWrite {
- address: pc,
- instruction: inst,
- memory_address: address,
- memory_value: val,
- })
- }
- }
+ self.trap(Trap::IllegalInstruction {
+ address: pc,
+ instruction: inst,
+ });
+ None
}
- _ => {
- panic!("Invalid store funct3code: 0x{:x}", inst.funct3());
+ } {
+ self.registers.write_word(inst.rd(), value);
+ }
+ },
+ isa::opcodes::LOAD => match inst.funct3() {
+ isa::funct3::LW => {
+ let imm = inst.i_imm();
+ let base = self.registers.read_word(inst.rs1());
+ let address = ((base as isa::SignedWord) + imm) as isa::Address;
+ let result = self.cache.borrow_mut().read_word(address);
+ match result {
+ Ok(value) =>
+ self.registers.write_word(inst.rd(), value),
+ Err(MemoryError::CacheMiss {..}) => return,
+ Err(MemoryError::InvalidAddress) => {
+ self.trap(Trap::IllegalRead {
+ address: pc,
+ instruction: inst,
+ memory_address: address,
+ });
+ }
}
},
- isa::opcodes::SYSTEM => match inst.i_imm() {
- 0x0 => {
- // System call
- println!("System call {}:", self.registers.read_word(isa::Register::X10));
- let address = self.registers.read_word(isa::Register::X11);
- println!("Argument {:X}: {:?}", address, self.cache.borrow_mut().read_word(address));
- }
- _ => {
-
+ _ => {
+ panic!("Invalid load funct3code: 0x{:x}", inst.funct3());
+ }
+ },
+ isa::opcodes::STORE => match inst.funct3() {
+ isa::funct3::SW => {
+ let imm = inst.s_imm();
+ let base = self.registers.read_word(inst.rs1());
+ let val = self.registers.read_word(inst.rs2());
+ let address = ((base as isa::SignedWord) + imm) as isa::Address;
+ let result = self.cache.borrow_mut().write_word(address, val);
+ match result {
+ Ok(()) => (),
+ Err(MemoryError::CacheMiss {..}) => return,
+ Err(MemoryError::InvalidAddress) => {
+ self.trap(Trap::IllegalWrite {
+ address: pc,
+ instruction: inst,
+ memory_address: address,
+ memory_value: val,
+ })
+ }
}
- },
+ }
_ => {
- panic!("Invalid opcode: 0x{:02X} at PC 0x{:X}", inst.opcode(), pc);
+ panic!("Invalid store funct3code: 0x{:x}", inst.funct3());
+ }
+ },
+ isa::opcodes::SYSTEM => match inst.i_imm() {
+ 0x0 => {
+ // System call
+ println!("System call {}:", self.registers.read_word(isa::Register::X10));
}
+ _ => {
+
+ }
+ },
+ _ => {
+ panic!("Invalid opcode: 0x{:02X} at PC 0x{:X}", inst.opcode(), pc);
}
}
- else {
- // trap
- }
self.pc += 4;
}
@@ -363,7 +356,12 @@ impl<'a> Simulator<'a> {
continue;
}
let inst = self.memory.borrow_mut().read_instruction(core.pc);
- core.step(inst);
+ if let Some(inst) = inst {
+ core.step(inst);
+ }
+ else {
+ // TODO: trap
+ }
ran = true;
}
if !ran {