rt docs, initial itcm wiring

This commit is contained in:
dcode 2019-03-21 12:29:49 +01:00
parent 3fc9f550ad
commit d4d5814fc2
4 changed files with 124 additions and 66 deletions

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@ -4367,17 +4367,20 @@ export function ensureGCHook(
// check if the class implements a custom GC function (only valid for library elements)
var members = classInstance.members;
if (classInstance.isDeclaredInLibrary) {
if (members !== null && members.has("__gc")) {
let gcPrototype = assert(members.get("__gc"));
assert(gcPrototype.kind == ElementKind.FUNCTION_PROTOTYPE);
let gcInstance = assert(program.resolver.resolveFunction(<FunctionPrototype>gcPrototype, null));
assert(gcInstance.is(CommonFlags.PRIVATE | CommonFlags.INSTANCE));
assert(!gcInstance.isAny(CommonFlags.AMBIENT | CommonFlags.VIRTUAL));
assert(gcInstance.signature.parameterTypes.length == 0);
assert(gcInstance.signature.returnType == Type.void);
gcInstance.internalName = classInstance.internalName + "~gc";
assert(compiler.compileFunction(gcInstance));
let index = compiler.ensureFunctionTableEntry(gcInstance);
if (members !== null && members.has("__iter")) {
let iterPrototype = assert(members.get("__iter"));
assert(iterPrototype.kind == ElementKind.FUNCTION_PROTOTYPE);
let iterInstance = assert(program.resolver.resolveFunction(<FunctionPrototype>iterPrototype, null));
assert(iterInstance.is(CommonFlags.PRIVATE | CommonFlags.INSTANCE));
assert(!iterInstance.isAny(CommonFlags.AMBIENT | CommonFlags.VIRTUAL));
let signature = iterInstance.signature;
let parameterTypes = signature.parameterTypes;
assert(parameterTypes.length == 1);
assert(parameterTypes[0].signatureReference);
assert(signature.returnType == Type.void);
iterInstance.internalName = classInstance.internalName + "~iter";
assert(compiler.compileFunction(iterInstance));
let index = compiler.ensureFunctionTableEntry(iterInstance);
classInstance.gcHookIndex = index;
return index;
}
@ -4408,7 +4411,7 @@ export function ensureGCHook(
functionTable.push("<placeholder>");
classInstance.gcHookIndex = gcHookIndex;
// if the class extends a base class, call its hook first (calls mark)
// if the class extends a base class, call its hook first
var baseInstance = classInstance.base;
if (baseInstance) {
assert(baseInstance.type.isManaged(program));
@ -4418,19 +4421,12 @@ export function ensureGCHook(
ensureGCHook(compiler, <Class>baseInstance.type.classReference)
),
[
module.createGetLocal(0, nativeSizeType)
module.createGetLocal(0, nativeSizeType), // this
module.createGetLocal(1, NativeType.I32) // fn
],
"FUNCSIG$" + (nativeSizeType == NativeType.I64 ? "vj" : "vi")
"FUNCSIG$" + (nativeSizeType == NativeType.I64 ? "vji" : "vii")
)
);
// if this class is the top-most base class, mark the instance
} else {
body.push(
module.createCall(assert(program.gcMarkInstance).internalName, [
module.createGetLocal(0, nativeSizeType)
], NativeType.None)
);
}
// mark instances assigned to own fields that are again references
@ -4442,16 +4438,20 @@ export function ensureGCHook(
if (type.isManaged(program)) {
let offset = (<Field>member).memoryOffset;
assert(offset >= 0);
body.push(
module.createCall(assert(program.gcMarkInstance).internalName, [
module.createLoad(
nativeSizeSize,
false,
module.createGetLocal(0, nativeSizeType),
nativeSizeType,
offset
)
], NativeType.None)
body.push( // fn(fieldValue)
module.createCallIndirect(
module.createGetLocal(1, NativeType.I32),
[
module.createLoad(
nativeSizeSize,
false,
module.createGetLocal(0, nativeSizeType),
nativeSizeType,
offset
),
],
"FUNCSIG$vi"
)
);
}
}
@ -4460,7 +4460,7 @@ export function ensureGCHook(
}
// add the function to the module and return its table index
var funcName = classInstance.internalName + "~gc";
var funcName = classInstance.internalName + "~iter";
module.addFunction(
funcName,
compiler.ensureFunctionType(null, Type.void, options.usizeType),

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@ -7,7 +7,6 @@ import {
compileCall as compileBuiltinCall,
compileAbort,
compileIterateRoots,
ensureGCHook,
BuiltinSymbols,
compileBuiltinArrayGet,
compileBuiltinArraySet,

View File

@ -4,13 +4,7 @@
@inline
const TRACE = false;
/** Size of a managed object header. */
// @ts-ignore: decorator
@inline
export const HEADER_SIZE: usize = (offsetof<ManagedObject>() + AL_MASK) & ~AL_MASK;
import { ITERATEROOTS } from "../runtime";
import { AL_MASK, MAX_SIZE_32 } from "../util/allocator";
import { ITERATEROOTS, HEADER_SIZE } from "../runtime";
/** Collector states. */
const enum State {
@ -51,6 +45,11 @@ var iter: ManagedObject;
/** Represents a managed object in memory, consisting of a header followed by the object's data. */
@unmanaged class ManagedObject {
// <HEADER>
classId: u32;
payloadSize: u32;
// </HEADER>
/** Pointer to the next object with color flags stored in the alignment bits. */
nextWithColor: usize;
@ -58,7 +57,9 @@ var iter: ManagedObject;
prev: ManagedObject;
/** Class-specific hook function called with the user-space reference. */
hookFn: (ref: usize) => void;
get hookFn(): (ref: usize) => void {
return changetype<(ref: usize) => void>(this.classId);
}
/** Gets the pointer to the next object. */
get next(): ManagedObject {
@ -128,10 +129,10 @@ function step(): void {
case State.INIT: {
if (TRACE) trace("gc~step/INIT");
fromSpace = changetype<ManagedObjectList>(memory.allocate(HEADER_SIZE));
fromSpace.hookFn = changetype<(ref: usize) => void>(<u32>-1); // would error
fromSpace.classId = -1; // would error
fromSpace.clear();
toSpace = changetype<ManagedObjectList>(memory.allocate(HEADER_SIZE));
toSpace.hookFn = changetype<(ref: usize) => void>(<u32>-1); // would error
toSpace.classId = -1; // would error
toSpace.clear();
iter = toSpace;
state = State.IDLE;
@ -140,7 +141,10 @@ function step(): void {
}
case State.IDLE: {
if (TRACE) trace("gc~step/IDLE");
ITERATEROOTS(__gc_mark);
ITERATEROOTS((ref: usize): void => {
var obj = refToObj(ref);
if (obj.color == white) obj.makeGray();
});
state = State.MARK;
if (TRACE) trace("gc~state = MARK");
break;
@ -161,7 +165,10 @@ function step(): void {
obj.hookFn(objToRef(obj));
} else {
if (TRACE) trace("gc~step/MARK finish");
ITERATEROOTS(__gc_mark);
ITERATEROOTS((ref: usize): void => {
var obj = refToObj(ref);
if (obj.color == white) obj.makeGray();
});
obj = iter.next;
if (obj === toSpace) {
let from = fromSpace;
@ -206,36 +213,26 @@ function objToRef(obj: ManagedObject): usize {
// @ts-ignore: decorator
@global @unsafe
export function __gc_allocate( // TODO: make this register only / reuse header
size: usize,
markFn: (ref: usize) => void
): usize {
if (TRACE) trace("gc.allocate", 1, size);
if (size > MAX_SIZE_32 - HEADER_SIZE) unreachable();
export function __gc_register(ref: usize): void {
if (TRACE) trace("gc.register", 2, ref);
step(); // also makes sure it's initialized
var obj = changetype<ManagedObject>(memory.allocate(HEADER_SIZE + size));
obj.hookFn = markFn;
var obj = refToObj(ref);
obj.color = white;
fromSpace.push(obj);
return objToRef(obj);
}
// @ts-ignore: decorator
@global @unsafe
export function __gc_link(parentRef: usize, childRef: usize): void {
if (TRACE) trace("gc.link", 2, parentRef, childRef);
export function __gc_retain(ref: usize, parentRef: usize): void {
if (TRACE) trace("gc.retain", 2, ref, parentRef);
var parent = refToObj(parentRef);
if (parent.color == i32(!white) && refToObj(childRef).color == white) parent.makeGray();
if (parent.color == i32(!white) && refToObj(ref).color == white) parent.makeGray();
}
// @ts-ignore: decorator
@global @unsafe
export function __gc_mark(ref: usize): void {
if (TRACE) trace("gc.mark", 1, ref);
if (ref) {
let obj = refToObj(ref);
if (obj.color == white) obj.makeGray();
}
export function __gc_release(ref: usize, parentRef: usize): void {
if (TRACE) trace("gc.release", 2, ref, parentRef);
}
// @ts-ignore: decorator

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@ -1,6 +1,68 @@
// The runtime provides a set of macros for dealing with common AssemblyScript internals, like
// allocation, memory management in general, integration with a (potenial) garbage collector
// and interfaces to hard-wired data types like buffers and their views. Doing so ensures that
// no matter which underlying implementation of a memory allocator or garbage collector is used,
// as long as all runtime/managed objects adhere to the runtime conventions, it'll all play well
// together. The compiler assumes that it can itself use the macros with the signatures declared
// in this file, so changing anything here will most likely require changes to the compiler, too.
import { AL_MASK, MAX_SIZE_32 } from "./util/allocator";
import { HEAP_BASE, memory } from "./memory";
// ALLOCATE(size)
// --------------
// Allocates a runtime object that might eventually make its way into GC'ed userland as a
// managed object. Implicitly prepends the common runtime header to the allocation.
//
// REALLOCATE(ref, size)
// ---------------------
// Changes the size of a previously allocated, but not yet registered, runtime object, for
// example when a pre-allocated buffer turned out to be too small or too large. This works by
// aligning dynamic allocations to actual block size internally so in the best case REALLOCATE
// only changes a size while in the worst case moves the object to larger block.
//
// DISCARD(ref)
// ------------
// Discards a runtime object that has not been registed and turned out to be unnecessary.
// Essentially undoes the forgoing ALLOCATE. Should be avoided where possible, of course.
//
// REGISTER<T>(ref)
// ----------------
// Registers a runtime object of kind T. Sets the internal class id within the runtime header
// and asserts that the object hasn't been registered yet. If a tracing garbage collector is
// present that requires initial insertion, the macro also forwards a call to it. Once a
// runtime object has been registed (makes it into userland), it cannot be DISCARD'ed anymore.
//
// RETAIN<T,TParent>(ref, parentRef)
// ---------------------------------
// Introduces a new reference to ref hold by parentRef. A tracing garbage collector will most
// likely link the runtime object within its internal graph when RETAIN is called, while a
// reference counting collector will increment the reference count.
//
// RELEASE<T,TParent>(ref, parentRef)
// ----------------------------------
// Releases a reference to ref hold by parentRef. A tracing garbage collector will most likely
// ignore this by design, while a reference counting collector decrements the reference count
// and potentially frees the runtime object.
//
// ALLOCATE_UNMANAGED(size)
// ------------------------
// Allocates an unmanaged struct-like object. This is used by the compiler as an abstraction
// to memory.allocate just in case, and is usually not used directly.
//
// WRAPARRAY<T>(buffer)
// --------------------
// Wraps a buffer's data as a standard array of element type T. Used by the compiler when
// creating an array from a static data segment, but is usually not used directly.
//
// HEADER
// ------
// The common runtime object header prepended to all managed objects. Has a size of 16 bytes in
// WASM32 and contains a classId (e.g. for instanceof checks), the allocation size (e.g. for
// .byteLength and .length computation) and additional reserved fields to be used by GC. If no
// GC is present, the HEADER is cut into half excluding the reserved fields, as indicated by
// HEADER_SIZE.
/** Whether the memory manager interface is implemented. */
// @ts-ignore: decorator, stub
@lazy export const MM_IMPLEMENTED: bool = isDefined(__memory_allocate);
@ -157,7 +219,7 @@ function doRetain(ref: usize, parentRef: usize): void {
assertRegistered(parentRef);
}
// @ts-ignore: stub
if (GC_IMPLEMENTED) __gc_link(changetype<usize>(ref), changetype<usize>(parentRef));
if (GC_IMPLEMENTED) __gc_retain(changetype<usize>(ref), changetype<usize>(parentRef));
}
/** Releases a registered object. */
@ -175,7 +237,7 @@ function doRelease(ref: usize, parentRef: usize): void {
assertRegistered(parentRef);
}
// @ts-ignore: stub
if (GC_IMPLEMENTED) __gc_unlink(changetype<usize>(ref), changetype<usize>(parentRef));
if (GC_IMPLEMENTED) __gc_release(changetype<usize>(ref), changetype<usize>(parentRef));
}
/** Discards an unregistered object that turned out to be unnecessary. */