diff options
author | Vincent Ambo <mail@tazj.in> | 2022-09-13T12·58+0300 |
---|---|---|
committer | tazjin <tazjin@tvl.su> | 2022-09-13T14·41+0000 |
commit | d5ee893fb15f9d2aae676763f12b507ad33243b0 (patch) | |
tree | 6731461c6ca5ff54982648b4372fac56d89b7ea9 | |
parent | a9914a79a0e55741efc7f8b6d694c043248abf2c (diff) |
refactor(tvix/eval): use CodeIdx wrapper for instruction pointer r/4838
As suggested by sterni in cl/6453. Change-Id: I3cf80d97c11fd7d085ab510f6be4b5f937c791ec Reviewed-on: https://cl.tvl.fyi/c/depot/+/6562 Reviewed-by: sterni <sternenseemann@systemli.org> Tested-by: BuildkiteCI
-rw-r--r-- | tvix/eval/src/observer.rs | 6 | ||||
-rw-r--r-- | tvix/eval/src/opcode.rs | 16 | ||||
-rw-r--r-- | tvix/eval/src/vm.rs | 21 |
3 files changed, 34 insertions, 9 deletions
diff --git a/tvix/eval/src/observer.rs b/tvix/eval/src/observer.rs index d662ea8a3867..e5562e3697d3 100644 --- a/tvix/eval/src/observer.rs +++ b/tvix/eval/src/observer.rs @@ -53,7 +53,7 @@ pub trait Observer { /// Called when the runtime *begins* executing an instruction. The /// provided stack is the state at the beginning of the operation. - fn observe_execute_op(&mut self, _ip: usize, _: &OpCode, _: &[Value]) {} + fn observe_execute_op(&mut self, _ip: CodeIdx, _: &OpCode, _: &[Value]) {} } #[derive(Default)] @@ -162,8 +162,8 @@ impl<W: Write> Observer for TracingObserver<W> { ); } - fn observe_execute_op(&mut self, ip: usize, op: &OpCode, stack: &[Value]) { - let _ = write!(&mut self.writer, "{:04} {:?}\t[ ", ip, op); + fn observe_execute_op(&mut self, ip: CodeIdx, op: &OpCode, stack: &[Value]) { + let _ = write!(&mut self.writer, "{:04} {:?}\t[ ", ip.0, op); for val in stack { let _ = write!(&mut self.writer, "{} ", val); diff --git a/tvix/eval/src/opcode.rs b/tvix/eval/src/opcode.rs index 27fceaf9677c..aee45d7a4452 100644 --- a/tvix/eval/src/opcode.rs +++ b/tvix/eval/src/opcode.rs @@ -1,6 +1,8 @@ //! This module implements the instruction set running on the abstract //! machine implemented by tvix. +use std::ops::{AddAssign, Sub}; + /// Index of a constant in the current code chunk. #[repr(transparent)] #[derive(Clone, Copy, Debug)] @@ -11,6 +13,20 @@ pub struct ConstantIdx(pub usize); #[derive(Clone, Copy, Debug)] pub struct CodeIdx(pub usize); +impl AddAssign<usize> for CodeIdx { + fn add_assign(&mut self, rhs: usize) { + *self = CodeIdx(self.0 + rhs) + } +} + +impl Sub<usize> for CodeIdx { + type Output = Self; + + fn sub(self, rhs: usize) -> Self::Output { + CodeIdx(self.0 - rhs) + } +} + /// Index of a value in the runtime stack. #[repr(transparent)] #[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd)] diff --git a/tvix/eval/src/vm.rs b/tvix/eval/src/vm.rs index 9fb51de544b3..ca024c9d65ec 100644 --- a/tvix/eval/src/vm.rs +++ b/tvix/eval/src/vm.rs @@ -13,9 +13,18 @@ use crate::{ }; struct CallFrame { + /// The lambda currently being executed. lambda: Rc<Lambda>, + + /// Optional captured upvalues of this frame (if a thunk or + /// closure if being evaluated). upvalues: Upvalues, - ip: usize, + + /// Instruction pointer to the instruction currently being + /// executed. + ip: CodeIdx, + + /// Stack offset, i.e. the frames "view" into the VM's full stack. stack_offset: usize, } @@ -134,7 +143,7 @@ impl<'o> VM<'o> { } fn inc_ip(&mut self) -> OpCode { - let op = self.chunk().code[self.frame().ip]; + let op = self.chunk()[self.frame().ip]; self.frame_mut().ip += 1; op } @@ -154,7 +163,7 @@ impl<'o> VM<'o> { /// Returns the source span of the instruction currently being /// executed. fn current_span(&self) -> codemap::Span { - self.chunk().get_span(CodeIdx(self.frame().ip - 1)) + self.chunk().get_span(self.frame().ip - 1) } /// Construct an error from the given ErrorKind and the source @@ -181,7 +190,7 @@ impl<'o> VM<'o> { let frame = CallFrame { lambda, upvalues, - ip: 0, + ip: CodeIdx(0), stack_offset: self.stack.len() - arg_count, }; @@ -200,7 +209,7 @@ impl<'o> VM<'o> { // Break the loop if this call frame has already run to // completion, pop it off, and return the value to the // caller. - if self.frame().ip == self.chunk().code.len() { + if self.frame().ip.0 == self.chunk().code.len() { self.frames.pop(); return Ok(self.pop()); } @@ -465,7 +474,7 @@ impl<'o> VM<'o> { let mut frame = self.frame_mut(); frame.lambda = lambda; frame.upvalues = closure.upvalues().clone(); - frame.ip = 0; // reset instruction pointer to beginning + frame.ip = CodeIdx(0); // reset instruction pointer to beginning } _ => return Err(self.error(ErrorKind::NotCallable)), |