Merge pull request #34 from typst/cfg-conditional

Put incremental compilation behind feature

.github/workflows/rust.yml

@@ -36,6 +36,9 @@ jobs:
           toolchain: ${{ matrix.rust }}
           override: true
 
+      - name: Dependency cache
+        uses: Swatinem/rust-cache@v1
+
       - name: Build
         uses: actions-rs/cargo@v1
         with:
@@ -47,3 +50,9 @@ jobs:
         with:
           command: test
           args: --manifest-path typst/Cargo.toml --all-features
+
+      - name: Test without incremental
+        uses: actions-rs/cargo@v1
+        with:
+          command: test
+          args: --manifest-path typst/Cargo.toml --no-default-features --features fs

Cargo.toml

@@ -5,9 +5,10 @@ authors = ["The Typst Project Developers"]
 edition = "2018"
 
 [features]
-default = ["cli", "fs"]
+default = ["cli", "fs", "layout-cache"]
 cli = ["anyhow", "fs", "same-file"]
 fs = ["dirs", "memmap2", "same-file", "walkdir"]
+layout-cache = []
 
 [workspace]
 members = ["bench"]

bench/Cargo.toml

@@ -5,9 +5,13 @@ authors = ["The Typst Project Developers"]
 edition = "2018"
 publish = false
 
+[features]
+default = ["layout-cache"]
+layout-cache = ["typst/layout-cache"]
+
 [dev-dependencies]
-criterion = "0.3"
-typst = { path = ".." }
+criterion = { version = "0.3", features = ["html_reports"] }
+typst = { path = "..", default-features = false, features = ["fs"] }
 
 [[bench]]
 name = "typst"

bench/src/bench.rs

@@ -1,14 +1,17 @@
+use std::cell::RefCell;
 use std::path::Path;
 use std::rc::Rc;
 
 use criterion::{criterion_group, criterion_main, Criterion};
 
-use typst::eval::eval;
-use typst::exec::exec;
+use typst::cache::Cache;
+use typst::eval::{eval, Module, Scope};
+use typst::exec::{exec, State};
 use typst::export::pdf;
-use typst::layout::layout;
+use typst::layout::{self, layout, Frame};
 use typst::loading::FsLoader;
 use typst::parse::parse;
+use typst::syntax;
 use typst::typeset;
 
 const FONT_DIR: &str = "../fonts";
@@ -16,42 +19,144 @@ const TYP_DIR: &str = "../tests/typ";
 const CASES: &[&str] = &["coma.typ", "text/basic.typ"];
 
 fn benchmarks(c: &mut Criterion) {
-    let mut loader = FsLoader::new();
-    loader.search_path(FONT_DIR);
-
-    let mut cache = typst::cache::Cache::new(&loader);
-    let scope = typst::library::new();
-    let state = typst::exec::State::default();
-
+    let ctx = Context::new();
     for case in CASES {
         let path = Path::new(TYP_DIR).join(case);
         let name = path.file_stem().unwrap().to_string_lossy();
+        let src = std::fs::read_to_string(&path).unwrap();
+        let case = Case::new(src, ctx.clone());
 
+        /// Bench with all caches.
         macro_rules! bench {
-            ($step:literal: $code:expr) => {
+            ($step:literal, setup = |$cache:ident| $setup:expr, code = $code:expr $(,)?) => {
                 c.bench_function(&format!("{}-{}", $step, name), |b| {
-                    b.iter(|| {
-                        cache.layout.clear();
-                        $code
-                    });
+                    b.iter_batched(
+                        || {
+                            let mut borrowed = ctx.borrow_mut();
+                            let $cache = &mut borrowed.cache;
+                            $setup
+                        },
+                        |_| $code,
+                        criterion::BatchSize::PerIteration,
+                    )
                 });
             };
+            ($step:literal, $code:expr) => {
+                c.bench_function(&format!("{}-{}", $step, name), |b| b.iter(|| $code));
+            };
         }
 
-        // Prepare intermediate results, run warm and fill caches.
-        let src = std::fs::read_to_string(&path).unwrap();
-        let tree = Rc::new(parse(&src).output);
-        let evaluated = eval(&mut loader, &mut cache, Some(&path), tree.clone(), &scope);
-        let executed = exec(&evaluated.output.template, state.clone());
-        let layouted = layout(&mut loader, &mut cache, &executed.output);
+        bench!("parse", case.parse());
+        bench!("eval", case.eval());
+        bench!("exec", case.exec());
 
-        // Bench!
-        bench!("parse": parse(&src));
-        bench!("eval": eval(&mut loader, &mut cache, Some(&path), tree.clone(), &scope));
-        bench!("exec": exec(&evaluated.output.template, state.clone()));
-        bench!("layout": layout(&mut loader, &mut cache, &executed.output));
-        bench!("typeset": typeset(&mut loader, &mut cache, Some(&path), &src, &scope, state.clone()));
-        bench!("pdf": pdf(&cache, &layouted));
+        #[cfg(not(feature = "layout-cache"))]
+        {
+            bench!("layout", case.layout());
+            bench!("typeset", case.typeset());
+        }
+
+        #[cfg(feature = "layout-cache")]
+        {
+            bench!(
+                "layout",
+                setup = |cache| cache.layout.clear(),
+                code = case.layout(),
+            );
+            bench!(
+                "typeset",
+                setup = |cache| cache.layout.clear(),
+                code = case.typeset(),
+            );
+            bench!("layout-cached", case.layout());
+            bench!("typeset-cached", case.typeset());
+        }
+
+        bench!("pdf", case.pdf());
+    }
+}
+
+/// The context required for benchmarking a case.
+struct Context {
+    loader: FsLoader,
+    cache: Cache,
+}
+
+impl Context {
+    fn new() -> Rc<RefCell<Self>> {
+        let mut loader = FsLoader::new();
+        loader.search_path(FONT_DIR);
+        let cache = Cache::new(&loader);
+        Rc::new(RefCell::new(Self { loader, cache }))
+    }
+}
+
+/// A test case with prepared intermediate results.
+struct Case {
+    ctx: Rc<RefCell<Context>>,
+    src: String,
+    scope: Scope,
+    state: State,
+    ast: Rc<syntax::Tree>,
+    module: Module,
+    tree: layout::Tree,
+    frames: Vec<Rc<Frame>>,
+}
+
+impl Case {
+    fn new(src: impl Into<String>, ctx: Rc<RefCell<Context>>) -> Self {
+        let mut borrowed = ctx.borrow_mut();
+        let Context { loader, cache } = &mut *borrowed;
+        let scope = typst::library::new();
+        let state = typst::exec::State::default();
+        let src = src.into();
+        let ast = Rc::new(parse(&src).output);
+        let module = eval(loader, cache, None, ast.clone(), &scope).output;
+        let tree = exec(&module.template, state.clone()).output;
+        let frames = layout(loader, cache, &tree);
+        drop(borrowed);
+        Self {
+            ctx,
+            src,
+            scope,
+            state,
+            ast,
+            module,
+            tree,
+            frames,
+        }
+    }
+
+    fn parse(&self) -> syntax::Tree {
+        parse(&self.src).output
+    }
+
+    fn eval(&self) -> Module {
+        let mut borrowed = self.ctx.borrow_mut();
+        let Context { loader, cache } = &mut *borrowed;
+        eval(loader, cache, None, self.ast.clone(), &self.scope).output
+    }
+
+    fn exec(&self) -> layout::Tree {
+        exec(&self.module.template, self.state.clone()).output
+    }
+
+    fn layout(&self) -> Vec<Rc<Frame>> {
+        let mut borrowed = self.ctx.borrow_mut();
+        let Context { loader, cache } = &mut *borrowed;
+        layout(loader, cache, &self.tree)
+    }
+
+    fn typeset(&self) -> Vec<Rc<Frame>> {
+        let mut borrowed = self.ctx.borrow_mut();
+        let Context { loader, cache } = &mut *borrowed;
+        let state = self.state.clone();
+        typeset(loader, cache, None, &self.src, &self.scope, state).output
+    }
+
+    fn pdf(&self) -> Vec<u8> {
+        let ctx = self.ctx.borrow();
+        pdf(&ctx.cache, &self.frames)
     }
 }
 

src/cache.rs

@@ -2,6 +2,7 @@
 
 use crate::font::FontCache;
 use crate::image::ImageCache;
+#[cfg(feature = "layout-cache")]
 use crate::layout::LayoutCache;
 use crate::loading::Loader;
 
@@ -12,6 +13,7 @@ pub struct Cache {
     /// Caches decoded images.
     pub image: ImageCache,
     /// Caches layouting artifacts.
+    #[cfg(feature = "layout-cache")]
     pub layout: LayoutCache,
 }
 
@@ -21,6 +23,7 @@ impl Cache {
         Self {
             font: FontCache::new(loader),
             image: ImageCache::new(),
+            #[cfg(feature = "layout-cache")]
             layout: LayoutCache::new(),
         }
     }

src/layout/background.rs

@@ -1,7 +1,8 @@
 use super::*;
 
 /// A node that places a rectangular filled background behind its child.
-#[derive(Debug, Clone, PartialEq, Hash)]
+#[derive(Debug, Clone, PartialEq)]
+#[cfg_attr(feature = "layout-cache", derive(Hash))]
 pub struct BackgroundNode {
     /// The kind of shape to use as a background.
     pub shape: BackgroundShape,

src/layout/fixed.rs

@@ -1,7 +1,8 @@
 use super::*;
 
 /// A node that can fix its child's width and height.
-#[derive(Debug, Clone, PartialEq, Hash)]
+#[derive(Debug, Clone, PartialEq)]
+#[cfg_attr(feature = "layout-cache", derive(Hash))]
 pub struct FixedNode {
     /// The fixed width, if any.
     pub width: Option<Linear>,

src/layout/grid.rs

@@ -1,7 +1,8 @@
 use super::*;
 
 /// A node that arranges its children in a grid.
-#[derive(Debug, Clone, PartialEq, Hash)]
+#[derive(Debug, Clone, PartialEq)]
+#[cfg_attr(feature = "layout-cache", derive(Hash))]
 pub struct GridNode {
     /// The `main` and `cross` directions of this grid.
     ///

src/layout/image.rs

@@ -4,7 +4,8 @@ use crate::image::ImageId;
 use ::image::GenericImageView;
 
 /// An image node.
-#[derive(Debug, Copy, Clone, PartialEq, Hash)]
+#[derive(Debug, Copy, Clone, PartialEq)]
+#[cfg_attr(feature = "layout-cache", derive(Hash))]
 pub struct ImageNode {
     /// The id of the image file.
     pub id: ImageId,

src/layout/incremental.rs

@@ -1,3 +1,4 @@
+#[cfg(feature = "layout-cache")]
 use std::collections::{hash_map::Entry, HashMap};
 use std::ops::Deref;
 
@@ -5,6 +6,7 @@ use super::*;
 
 /// Caches layouting artifacts.
 #[derive(Default, Debug, Clone)]
+#[cfg(feature = "layout-cache")]
 pub struct LayoutCache {
     /// Maps from node hashes to the resulting frames and regions in which the
     /// frames are valid. The right hand side of the hash map is a vector of
@@ -15,6 +17,7 @@ pub struct LayoutCache {
     age: usize,
 }
 
+#[cfg(feature = "layout-cache")]
 impl LayoutCache {
     /// Create a new, empty layout cache.
     pub fn new() -> Self {
@@ -100,6 +103,7 @@ impl LayoutCache {
 
 /// Cached frames from past layouting.
 #[derive(Debug, Clone)]
+#[cfg(feature = "layout-cache")]
 pub struct FramesEntry {
     /// The cached frames for a node.
     pub frames: Vec<Constrained<Rc<Frame>>>,
@@ -112,6 +116,7 @@ pub struct FramesEntry {
     temperature: [usize; 5],
 }
 
+#[cfg(feature = "layout-cache")]
 impl FramesEntry {
     /// Construct a new instance.
     pub fn new(frames: Vec<Constrained<Rc<Frame>>>, level: usize) -> Self {
@@ -205,6 +210,7 @@ impl Constraints {
         }
     }
 
+    #[cfg(feature = "layout-cache")]
     fn check(&self, regions: &Regions) -> bool {
         if self.expand != regions.expand {
             return false;

src/layout/mod.rs

@@ -24,9 +24,12 @@ pub use stack::*;
 
 use std::any::Any;
 use std::fmt::{self, Debug, Formatter};
-use std::hash::{Hash, Hasher};
+use std::hash::Hash;
+#[cfg(feature = "layout-cache")]
+use std::hash::Hasher;
 use std::rc::Rc;
 
+#[cfg(feature = "layout-cache")]
 use fxhash::FxHasher64;
 
 use crate::cache::Cache;
@@ -35,7 +38,12 @@ use crate::loading::Loader;
 
 /// Layout a tree into a collection of frames.
 pub fn layout(loader: &mut dyn Loader, cache: &mut Cache, tree: &Tree) -> Vec<Rc<Frame>> {
-    tree.layout(&mut LayoutContext { loader, cache, level: 0 })
+    tree.layout(&mut LayoutContext {
+        loader,
+        cache,
+        #[cfg(feature = "layout-cache")]
+        level: 0,
+    })
 }
 
 /// A tree of layout nodes.
@@ -77,22 +85,35 @@ impl PageRun {
 /// A wrapper around a dynamic layouting node.
 pub struct AnyNode {
     node: Box<dyn Bounds>,
+    #[cfg(feature = "layout-cache")]
     hash: u64,
 }
 
 impl AnyNode {
     /// Create a new instance from any node that satisifies the required bounds.
+    #[cfg(feature = "layout-cache")]
     pub fn new<T>(node: T) -> Self
     where
         T: Layout + Debug + Clone + PartialEq + Hash + 'static,
     {
-        let mut state = FxHasher64::default();
-        node.type_id().hash(&mut state);
-        node.hash(&mut state);
-        let hash = state.finish();
+        let hash = {
+            let mut state = FxHasher64::default();
+            node.type_id().hash(&mut state);
+            node.hash(&mut state);
+            state.finish()
+        };
 
         Self { node: Box::new(node), hash }
     }
+
+    /// Create a new instance from any node that satisifies the required bounds.
+    #[cfg(not(feature = "layout-cache"))]
+    pub fn new<T>(node: T) -> Self
+    where
+        T: Layout + Debug + Clone + PartialEq + 'static,
+    {
+        Self { node: Box::new(node) }
+    }
 }
 
 impl Layout for AnyNode {
@@ -101,15 +122,20 @@ impl Layout for AnyNode {
         ctx: &mut LayoutContext,
         regions: &Regions,
     ) -> Vec<Constrained<Rc<Frame>>> {
-        ctx.level += 1;
-        let frames =
-            ctx.cache.layout.get(self.hash, regions.clone()).unwrap_or_else(|| {
-                let frames = self.node.layout(ctx, regions);
-                ctx.cache.layout.insert(self.hash, frames.clone(), ctx.level - 1);
-                frames
-            });
-        ctx.level -= 1;
-        frames
+        #[cfg(feature = "layout-cache")]
+        {
+            ctx.level += 1;
+            let frames =
+                ctx.cache.layout.get(self.hash, regions.clone()).unwrap_or_else(|| {
+                    let frames = self.node.layout(ctx, regions);
+                    ctx.cache.layout.insert(self.hash, frames.clone(), ctx.level - 1);
+                    frames
+                });
+            ctx.level -= 1;
+            frames
+        }
+        #[cfg(not(feature = "layout-cache"))]
+        self.node.layout(ctx, regions)
     }
 }
 
@@ -117,6 +143,7 @@ impl Clone for AnyNode {
     fn clone(&self) -> Self {
         Self {
             node: self.node.dyn_clone(),
+            #[cfg(feature = "layout-cache")]
             hash: self.hash,
         }
     }
@@ -128,6 +155,7 @@ impl PartialEq for AnyNode {
     }
 }
 
+#[cfg(feature = "layout-cache")]
 impl Hash for AnyNode {
     fn hash<H: Hasher>(&self, state: &mut H) {
         state.write_u64(self.hash);
@@ -184,6 +212,7 @@ pub struct LayoutContext<'a> {
     /// A cache for loaded fonts and artifacts from past layouting.
     pub cache: &'a mut Cache,
     /// How deeply nested the current layout tree position is.
+    #[cfg(feature = "layout-cache")]
     pub level: usize,
 }
 

src/layout/pad.rs

@@ -1,7 +1,8 @@
 use super::*;
 
 /// A node that adds padding to its child.
-#[derive(Debug, Clone, PartialEq, Hash)]
+#[derive(Debug, Clone, PartialEq)]
+#[cfg_attr(feature = "layout-cache", derive(Hash))]
 pub struct PadNode {
     /// The amount of padding.
     pub padding: Sides<Linear>,

src/layout/par.rs

@@ -11,7 +11,8 @@ use crate::util::{RangeExt, SliceExt};
 type Range = std::ops::Range<usize>;
 
 /// A node that arranges its children into a paragraph.
-#[derive(Debug, Clone, PartialEq, Hash)]
+#[derive(Debug, Clone, PartialEq)]
+#[cfg_attr(feature = "layout-cache", derive(Hash))]
 pub struct ParNode {
     /// The inline direction of this paragraph.
     pub dir: Dir,
@@ -22,7 +23,8 @@ pub struct ParNode {
 }
 
 /// A child of a paragraph node.
-#[derive(Clone, PartialEq, Hash)]
+#[derive(Clone, PartialEq)]
+#[cfg_attr(feature = "layout-cache", derive(Hash))]
 pub enum ParChild {
     /// Spacing between other nodes.
     Spacing(Length),

src/layout/stack.rs

@@ -3,7 +3,8 @@ use decorum::N64;
 use super::*;
 
 /// A node that stacks its children.
-#[derive(Debug, Clone, PartialEq, Hash)]
+#[derive(Debug, Clone, PartialEq)]
+#[cfg_attr(feature = "layout-cache", derive(Hash))]
 pub struct StackNode {
     /// The `main` and `cross` directions of this stack.
     ///
@@ -19,7 +20,8 @@ pub struct StackNode {
 }
 
 /// A child of a stack node.
-#[derive(Debug, Clone, PartialEq, Hash)]
+#[derive(Debug, Clone, PartialEq)]
+#[cfg_attr(feature = "layout-cache", derive(Hash))]
 pub enum StackChild {
     /// Spacing between other nodes.
     Spacing(Length),

tests/typeset.rs

@@ -272,46 +272,49 @@ fn test_part(
         }
     }
 
-    let reference_cache = cache.layout.clone();
-    for level in 0 .. reference_cache.levels() {
-        cache.layout = reference_cache.clone();
-        cache.layout.retain(|x| x == level);
-        if cache.layout.frames.is_empty() {
-            continue;
+    #[cfg(feature = "layout-cache")]
+    {
+        let reference_cache = cache.layout.clone();
+        for level in 0 .. reference_cache.levels() {
+            cache.layout = reference_cache.clone();
+            cache.layout.retain(|x| x == level);
+            if cache.layout.frames.is_empty() {
+                continue;
+            }
+
+            cache.layout.turnaround();
+
+            let cached_result = layout(loader, cache, &executed.output);
+
+            let misses = cache
+                .layout
+                .frames
+                .iter()
+                .flat_map(|(_, e)| e)
+                .filter(|e| e.level == level && !e.hit() && e.age() == 2)
+                .count();
+
+            if misses > 0 {
+                ok = false;
+                println!(
+                    "    Recompilation had {} cache misses on level {} (Subtest {}) ❌",
+                    misses, level, i
+                );
+            }
+
+            if cached_result != layouted {
+                ok = false;
+                println!(
+                    "    Recompilation of subtest {} differs from clean pass ❌",
+                    i
+                );
+            }
         }
 
+        cache.layout = reference_cache;
         cache.layout.turnaround();
-
-        let cached_result = layout(loader, cache, &executed.output);
-
-        let misses = cache
-            .layout
-            .frames
-            .iter()
-            .flat_map(|(_, e)| e)
-            .filter(|e| e.level == level && !e.hit() && e.age() == 2)
-            .count();
-
-        if misses > 0 {
-            ok = false;
-            println!(
-                "    Recompilation had {} cache misses on level {} (Subtest {}) ❌",
-                misses, level, i
-            );
-        }
-
-        if cached_result != layouted {
-            ok = false;
-            println!(
-                "    Recompilation of subtest {} differs from clean pass ❌",
-                i
-            );
-        }
     }
 
-    cache.layout = reference_cache;
-    cache.layout.turnaround();
-
     if !compare_ref {
         layouted.clear();
     }