IR: document lock priority.

2021-02-18 15:02:07 +03:00
parent 60f38369f1
commit bff6e9b972
1 changed files with 12 additions and 0 deletions
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+# Priority of locks in parallel runs of the JVM IR backend
+
+To avoid deadlocks in backend code, please make sure that a lock that comes earlier in the list
+never gets acquired by a thread that already holds one of the locks that come later.
+
+1. `JvmBackendContext.inlineMethodGenerationLock`. Used to prevent concurrent generation of inline functions.
+1. Global `IrLock` instance. Used in `SymbolTable`, 
+   `lazyVar` instances in `IrLazyDeclaration`, `Fir2IrLazyDeclaration` subclasses,
+   `Fir2IrDeclarationStorage`.
+1. - lock in `ClassBuilderAndSourceFileList.asBytes`.
+   - lock on `methodNode` in `InlineCodegen.cloneMethodNode`.
+   - Locks protecting `InlineCache` maps.