merge: Some profile-guided optimization (#1305)

Recursive `buildNested` has made the profiler output harder to read:

![image](https://github.com/user-attachments/assets/719c6741-7e96-4d56-9551-f121bc0bc9ce)

After turning it into iteration, it's easier:

![image](https://github.com/user-attachments/assets/2f785a9c-320d-49e3-849c-7eef762c30bf)

The `sourcePosForSubExpr` is taking a lot of time. Shit!

jit-compiler/src/main/java/org/aya/compiler/AsmOutputCollector.java

@@ -18,7 +18,7 @@ record Default(@NotNull MutableMap<Path, byte[]> output) implements AsmOutputCol
     public Default() { this(MutableMap.create()); }
 
     public static @NotNull Path from(@NotNull ImmutableSeq<String> components) {
-      return Path.of(components.getFirst(), components.view().drop(1).toArray(new String[components.size() - 1]));
+      return Path.of(components.getFirst(), components.view().drop(1).toArray(String[]::new));
     }
 
     public static @NotNull Path getPath(@NotNull ClassDesc className) {

jit-compiler/src/main/java/org/aya/compiler/free/morphism/asm/AsmClassBuilder.java

@@ -65,13 +65,8 @@ public AsmClassBuilder(
     )));
   }
 
-  public @NotNull ClassDesc owner() {
-    return classData.className();
-  }
-
-  public @NotNull ClassDesc ownerSuper() {
-    return classData.classSuper();
-  }
+  public @NotNull ClassDesc owner() { return classData.className(); }
+  public @NotNull ClassDesc ownerSuper() { return classData.classSuper(); }
 
   @Override
   public void buildNestedClass(@NotNull CompiledAya compiledAya, @NotNull String name, @NotNull Class<?> superclass, @NotNull Consumer<FreeClassBuilder> builder) {
@@ -178,7 +173,8 @@ public void postBuild() {
         InnerClassInfo.of(owner().nested(cd), Optional.of(owner()), Optional.of(cd), ClassData.AF_NESTED));
     } else {
       assert nestedMembers.isEmpty();
-      innerClassesEntries = ImmutableSeq.of(InnerClassInfo.of(owner(), Optional.of(outerClassData.data().classSuper()), Optional.of(outerClassData.thisName()), ClassData.AF_NESTED));
+      innerClassesEntries = ImmutableSeq.of(InnerClassInfo.of(owner(), Optional.of(outerClassData.data().classSuper()),
+        Optional.of(outerClassData.thisName()), ClassData.AF_NESTED));
     }
 
     if (innerClassesEntries.isNotEmpty()) {

syntax/src/main/java/org/aya/syntax/concrete/Expr.java

@@ -8,6 +8,7 @@
 
 import kala.collection.SeqView;
 import kala.collection.immutable.ImmutableSeq;
+import kala.collection.mutable.MutableArrayList;
 import kala.control.Either;
 import kala.value.MutableValue;
 import org.aya.generic.AyaDocile;
@@ -449,8 +450,7 @@ public void forEach(@NotNull Consumer<Expr> f) {
     ///
     /// @param generator `x * y` part above
     /// @param binds     `x <- [1, 2, 3], y <- [4, 5, 6]` part above
-    /// @param names     the bind (`>>=`) function, it is [#monadBind] in default,
-    ///                  the pure (`return`) function, it is [#functorPure] in default
+    /// @param names     bind (`>>=`) is [#monadBind] by default and pure (`return`) is [#functorPure] by default
     /// @apiNote a ArrayCompBlock will be desugar to a do-block. For the example above,
     /// it will be desugared to `do x <- [1, 2, 3], y <- [4, 5, 6], return x * y`
     public record CompBlock(
@@ -474,9 +474,7 @@ public void forEach(@NotNull PosedConsumer<Expr> f) {
       }
     }
 
-    /**
-     * helper constructor, also find constructor calls easily in IDE
-     */
+    /// Helper constructor, also find constructor calls easily in IDE
     public static Array newList(@NotNull ImmutableSeq<WithPos<Expr>> exprs) {
       return new Array(Either.right(new ElementList(exprs)));
     }
@@ -639,11 +637,15 @@ record Match(
     @NotNull WithPos<E> body,
     @NotNull BiFunction<P, WithPos<E>, E> constructor
   ) {
-    if (params.isEmpty()) return body;
-    var drop = params.drop(1);
-    var subPos = body.sourcePos().sourcePosForSubExpr(sourcePos.file(),
-      drop.map(SourceNode::sourcePos));
-    return new WithPos<>(sourcePos, constructor.apply(params.getFirst(),
-      buildNested(subPos, drop, body, constructor)));
+    record StackData<P>(P p, SourcePos pos) { }
+    var subPoses = MutableArrayList.<StackData<P>>create();
+    while (!params.isEmpty()) {
+      subPoses.append(new StackData<>(params.getFirst(), sourcePos));
+      params = params.drop(1);
+      sourcePos = body.sourcePos().sourcePosForSubExpr(sourcePos.file(),
+        params.map(SourceNode::sourcePos));
+    }
+    return subPoses.foldRight(body, (data, acc) ->
+      new WithPos<>(data.pos, constructor.apply(data.p, acc)));
   }
 }

syntax/src/main/java/org/aya/syntax/ref/ModulePath.java

@@ -1,4 +1,4 @@
-// Copyright (c) 2020-2024 Tesla (Yinsen) Zhang.
+// Copyright (c) 2020-2025 Tesla (Yinsen) Zhang.
 // Use of this source code is governed by the MIT license that can be found in the LICENSE.md file.
 package org.aya.syntax.ref;
 
@@ -10,37 +10,22 @@
 import java.io.Serializable;
 
 public record ModulePath(@NotNull ImmutableSeq<String> module) implements Serializable {
-  public static @NotNull ModulePath of(@NotNull String... names) {
-    return new ModulePath(ImmutableSeq.from(names));
-  }
+  public static @NotNull ModulePath of(@NotNull String... names) { return new ModulePath(ImmutableSeq.from(names)); }
 
   public boolean isInModule(@NotNull ModulePath other) {
     var moduleName = other.module;
     if (module.sizeLessThan(moduleName.size())) return false;
     return module.sliceView(0, moduleName.size()).sameElements(moduleName);
   }
 
-  public ModulePath dropLast(int n) {
-    return new ModulePath(module.dropLast(n));
-  }
-
-  public boolean sameElements(ModulePath other) {
-    return module.sameElements(other.module);
-  }
-
-  public @NotNull ModuleName.Qualified asName() {
-    return ModuleName.qualified(module);
-  }
-
-  public @NotNull ModulePath derive(@NotNull String modName) {
-    return new ModulePath(module.appended(modName));
-  }
-
+  public ModulePath dropLast(int n) { return new ModulePath(module.dropLast(n)); }
+  public boolean sameElements(ModulePath other) { return module.sameElements(other.module); }
+  public @NotNull ModuleName.Qualified asName() { return ModuleName.qualified(module); }
+  public @NotNull ModulePath derive(@NotNull String modName) { return new ModulePath(module.appended(modName)); }
   public @NotNull ModulePath derive(@NotNull ModulePath modName) {
     return new ModulePath(module.concat(modName.module));
   }
-
-  @Override public String toString() { return QualifiedID.join(module); }
+  @Override public @NotNull String toString() { return QualifiedID.join(module); }
   public boolean isEmpty() { return module.isEmpty(); }
   public int size() { return module.size(); }
   public @NotNull String last() { return module.getLast(); }

tools/src/main/java/org/aya/util/error/SourcePos.java

@@ -1,16 +1,16 @@
-// Copyright (c) 2020-2024 Tesla (Yinsen) Zhang.
+// Copyright (c) 2020-2025 Tesla (Yinsen) Zhang.
 // Use of this source code is governed by the MIT license that can be found in the LICENSE.md file.
 package org.aya.util.error;
 
+import java.util.Objects;
+
 import com.intellij.openapi.util.TextRange;
 import com.intellij.openapi.util.text.LineColumn;
 import com.intellij.openapi.util.text.StringUtil;
 import kala.collection.SeqView;
 import org.jetbrains.annotations.Contract;
 import org.jetbrains.annotations.NotNull;
 
-import java.util.Objects;
-
 /**
  * Position in source code for error reporting only.
  *
@@ -108,10 +108,6 @@ public boolean oneLinear() {
     return startLine == endLine;
   }
 
-  public @NotNull SourcePos sourcePosForSubExpr(@NotNull SeqView<SourcePos> params) {
-    return sourcePosForSubExpr(file, params);
-  }
-
   public @NotNull SourcePos sourcePosForSubExpr(@NotNull SourceFile sourceFile, @NotNull SeqView<SourcePos> params) {
     var restParamSourcePos = params.fold(SourcePos.NONE, (acc, it) -> {
       if (acc == SourcePos.NONE) return it;
@@ -129,7 +125,7 @@ public boolean oneLinear() {
     );
   }
 
-  @Override public String toString() {
+  @Override public @NotNull String toString() {
     return "(" + tokenStartIndex + "-" + tokenEndIndex + ") [" + lineColumnString() + ']';
   }
   public @NotNull String lineColumnString() {