Reduce memory usage of holding BIR and source files

[heshanpadmasiri]

Purpose

Reduce memory usage of holding BIR and source files by holding them as weak references. If the actual values are GCed we will reload the file from disk seamlessly.

Also more aggressively prune negative atoms in ListInhabited

Approach

Describe how you are implementing the solutions along with the design details.

Samples

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Remarks

List any other known issues, related PRs, TODO items, or any other notes related to the PR.

Check List

• Read the Contributing Guide
• Updated Change Log
• Checked Tooling Support (#)
• Added necessary tests
  • Unit Tests
  • Spec Conformance Tests
  • Integration Tests
  • Ballerina By Example Tests
• Increased Test Coverage
• Added necessary documentation
  • API documentation
  • Module documentation in Module.md files
  • Ballerina By Examples

[Copilot]

Pull Request Overview

This PR reduces memory usage by holding BIR and source file contents as weak references and lazy-loading them when needed.

• Introduces abstract BIRPackageFile and StringTextDocument with eager and lazy variants.
• Updates ModuleContext to store BIR bytes in a WeakReference and adds a lazy reload path.
• Refactors document loading (ProjectFiles, GeneralFSPackageRepository, etc.) to use Supplier for on-demand file reading.

Reviewed Changes

Copilot reviewed 23 out of 23 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
tests/ballerina-test-utils/src/main/java/org/ballerinalang/test/BCompileUtil.java	Update import and use BIRPackageFile getter for binary content
misc/ballerina-bindgen/src/main/java/org/ballerinalang/bindgen/utils/BindgenFileGenerator.java	Add Supplier import for lazy file loading
compiler/ballerina-tools-api/src/main/java/io/ballerina/tools/text/TextDocuments.java	Support lazy text document creation with Supplier
compiler/ballerina-tools-api/src/main/java/io/ballerina/tools/text/StringTextDocument.java	Refactor to abstract base and implement eager/lazy variants
compiler/ballerina-lang/src/main/java/org/wso2/ballerinalang/programfile/PackageFileWriter.java	Use BIRPackageFile getter for writing binary content
compiler/ballerina-lang/src/main/java/org/wso2/ballerinalang/programfile/CompiledBinaryFile.java	Remove legacy BIRPackageFile inner class
compiler/ballerina-lang/src/main/java/org/wso2/ballerinalang/programfile/BIRPackageFile.java	Introduce abstract BIRPackageFile with eager and lazy implementations
compiler/ballerina-lang/src/main/java/org/wso2/ballerinalang/compiler/semantics/model/symbols/BPackageSymbol.java	Update import to new BIRPackageFile class
compiler/ballerina-lang/src/main/java/org/wso2/ballerinalang/compiler/packaging/converters/FileSystemSourceInput.java	Change syntax tree loading to use lazy content supplier
compiler/ballerina-lang/src/main/java/org/wso2/ballerinalang/compiler/bir/writer/BIRBinaryWriter.java	Simplify references to BIRPackageFile constants
compiler/ballerina-lang/src/main/java/org/wso2/ballerinalang/compiler/BIRPackageSymbolEnter.java	Migrate definePackage to use ModuleContext and lazy BIRPackageFile
compiler/ballerina-lang/src/main/java/org/ballerinalang/repository/fs/GeneralFSPackageRepository.java	Use supplier for lazy document loading
compiler/ballerina-lang/src/main/java/io/ballerina/projects/internal/ProjectFiles.java	Refactor document loading to use Supplier
compiler/ballerina-lang/src/main/java/io/ballerina/projects/internal/PackageConfigCreator.java	Use Supplier-based DocumentConfig for lazy content
compiler/ballerina-lang/src/main/java/io/ballerina/projects/internal/DocumentData.java	Abstract DocumentData with eager and lazy subclasses
compiler/ballerina-lang/src/main/java/io/ballerina/projects/internal/BalaFiles.java	Refactor BalaFiles document loading to use lazy Supplier
compiler/ballerina-lang/src/main/java/io/ballerina/projects/ModuleDescriptor.java	Make moduleCompilationId() public for lazy BIR loader
compiler/ballerina-lang/src/main/java/io/ballerina/projects/ModuleContext.java	Store BIR bytes in WeakReference and add lazy loader
compiler/ballerina-lang/src/main/java/io/ballerina/projects/MdDocumentContext.java	Update to use Supplier-based DocumentConfig
compiler/ballerina-lang/src/main/java/io/ballerina/projects/DocumentContext.java	Refactor to use DocumentConfig abstraction for content
compiler/ballerina-lang/src/main/java/io/ballerina/projects/DocumentConfig.java	Introduce lazy DocumentConfig abstraction with Supplier
compiler/ballerina-lang/src/main/java/io/ballerina/projects/CodeModifierManager.java	Create DocumentConfig with Supplier for modified docs
compiler/ballerina-lang/src/main/java/io/ballerina/projects/CodeGeneratorManager.java	Use Supplier for generated document content

Comments suppressed due to low confidence (3)

compiler/ballerina-lang/src/main/java/org/wso2/ballerinalang/programfile/BIRPackageFile.java:41

• [nitpick] Class name 'EagerBirPackageFile' uses 'Bir' casing, but 'BIR' is treated as an acronym elsewhere. Rename to 'EagerBIRPackageFile' for consistency.

    public static class EagerBirPackageFile extends BIRPackageFile {

compiler/ballerina-lang/src/main/java/org/wso2/ballerinalang/programfile/BIRPackageFile.java:61

• [nitpick] Class name 'LazyBirPackageFile' uses 'Bir' casing, but 'BIR' is an acronym. Consider renaming to 'LazyBIRPackageFile' to keep naming consistent.

    public static class LazyBirPackageFile extends BIRPackageFile {

compiler/ballerina-lang/src/main/java/io/ballerina/projects/ModuleContext.java:76

• [nitpick] The constant name 'DEFAULT_BIR_BYTE' suggests a single byte but holds a byte array reference. Rename to 'DEFAULT_BIR_BYTES' or 'DEFAULT_BIR_BYTES_REF' for clarity.

    private static final WeakReference<byte[]> DEFAULT_BIR_BYTE = new WeakReference<>(new byte[0]);