@samitouri / QOS-React / commits / 7f5bac171e

TryStatement: try terminal scaffolding

This PR adds the other piece, a 'try' terminal which represents try/catch and the possibility of fallthrough to the code afterwards. For now `finally` is unsupported. We don't yet produce these terminals, see later in the stack.

Joe Savona committed Sep 7, 2023 at 14:22 UTC 7f5bac171eaef4a9576d25417916a2b014016625

11 files changed +131 -2

compiler/packages/babel-plugin-react-forget/src/HIR/HIR.ts

+20 -2

@@ -138,7 +138,8 @@ export type ReactiveTerminal =

138 | ReactiveForTerminal

139 | ReactiveForOfTerminal

140 | ReactiveIfTerminal

141 - | ReactiveLabelTerminal;

141 + | ReactiveLabelTerminal

142 + | ReactiveTryTerminal;

143

144 export type ReactiveBreakTerminal = {

145 kind: "break";

@@ -209,6 +210,12 @@ export type ReactiveLabelTerminal = {

210 block: ReactiveBlock;

211 id: InstructionId;

212 };

213 +export type ReactiveTryTerminal = {

214 + kind: "try";

215 + block: ReactiveBlock;

216 + handler: ReactiveBlock;

217 + id: InstructionId;

218 +};

219

220 /**

221 * A function lowered to HIR form, ie where its body is lowered to an HIR control-flow graph

@@ -280,7 +287,8 @@ export type Terminal =

287 | OptionalTerminal

288 | LabelTerminal

289 | SequenceTerminal

283 - | MaybeThrowTerminal;

290 + | MaybeThrowTerminal

291 + | TryTerminal;

292

293 function _staticInvariantTerminalHasLocation(

294 terminal: Terminal

@@ -445,6 +453,16 @@ export type SequenceTerminal = {

453 loc: SourceLocation;

454 };

455

456 +export type TryTerminal = {

457 + kind: "try";

458 + block: BlockId;

459 + handler: BlockId;

460 + // TODO: support `finally`

461 + fallthrough: BlockId | null;

462 + id: InstructionId;

463 + loc: SourceLocation;

464 +};

465 +

466 export type MaybeThrowTerminal = {

467 kind: "maybe-throw";

468 continuation: BlockId;

compiler/packages/babel-plugin-react-forget/src/HIR/HIRBuilder.ts

@@ -754,6 +754,10 @@ export function reversePostorderBlocks(func: HIR): void {

754 visit(terminal.continuation);

755 break;

756 }

757 + case "try": {

758 + visit(terminal.block);

759 + break;

760 + }

761 case "unsupported": {

762 break;

763 }

compiler/packages/babel-plugin-react-forget/src/HIR/PrintHIR.ts

@@ -80,6 +80,7 @@ export function printMixedHIR(

80 return printInstruction(value);

81 }

82 switch (value.kind) {

83 + case "try":

84 case "maybe-throw":

85 case "sequence":

86 case "label":

@@ -235,6 +236,14 @@ export function printTerminal(terminal: Terminal): Array<string> | string {

236 value = `MaybeThrow continuation=bb${terminal.continuation} handler=bb${terminal.handler}`;

237 break;

238 }

239 + case "try": {

240 + value = `Try block=bb${terminal.block} catch=bb${

241 + terminal.handler

242 + } fallthrough=${

243 + terminal.fallthrough != null ? `bb${terminal.fallthrough}` : ""

244 + }`;

245 + break;

246 + }

247 default: {

248 assertExhaustive(

249 terminal,

compiler/packages/babel-plugin-react-forget/src/HIR/visitors.ts

+29

@@ -742,6 +742,20 @@ export function mapTerminalSuccessors(

742 loc: terminal.loc,

743 };

744 }

745 + case "try": {

746 + const block = fn(terminal.block);

747 + const handler = fn(terminal.handler);

748 + const fallthrough =

749 + terminal.fallthrough !== null ? fn(terminal.fallthrough) : null;

750 + return {

751 + kind: "try",

752 + block,

753 + handler,

754 + fallthrough,

755 + id: makeInstructionId(0),

756 + loc: terminal.loc,

757 + };

758 + }

759 case "unsupported": {

760 return terminal;

761 }

@@ -769,6 +783,7 @@ export function terminalFallthrough(terminal: Terminal): BlockId | null {

783 case "unsupported": {

784 return null;

785 }

786 + case "try":

787 case "do-while":

788 case "for-of":

789 case "for":

@@ -858,6 +873,14 @@ export function mapOptionalFallthroughs(

873 const _: BlockId = terminal.fallthrough;

874 break;

875 }

876 + case "try": {

877 + if (terminal.fallthrough !== null) {

878 + terminal.fallthrough = fn(terminal.fallthrough);

879 + } else {

880 + terminal.fallthrough = null;

881 + }

882 + break;

883 + }

884 default: {

885 assertExhaustive(

886 terminal,

@@ -935,6 +958,10 @@ export function* eachTerminalSuccessor(terminal: Terminal): Iterable<BlockId> {

958 yield terminal.handler;

959 break;

960 }

961 + case "try": {

962 + yield terminal.block;

963 + break;

964 + }

965 case "unsupported":

966 break;

967 default: {

@@ -974,6 +1001,7 @@ export function mapTerminalOperands(

1001 terminal.value = fn(terminal.value);

1002 break;

1003 }

1004 + case "try":

1005 case "maybe-throw":

1006 case "sequence":

1007 case "label":

@@ -1023,6 +1051,7 @@ export function* eachTerminalOperand(terminal: Terminal): Iterable<Place> {

1051 yield terminal.value;

1052 break;

1053 }

1054 + case "try":

1055 case "maybe-throw":

1056 case "sequence":

1057 case "label":

compiler/packages/babel-plugin-react-forget/src/ReactiveScopes/BuildReactiveFunction.ts

+37

@@ -637,12 +637,49 @@ class Driver {

637 break;

638 }

639 case "maybe-throw": {

640 + // ReactiveFunction does not explicit model maybe-throw semantics,

641 + // so these terminals flatten away

642 this.visitBlock(

643 this.cx.ir.blocks.get(terminal.continuation)!,

644 blockValue

645 );

646 break;

647 }

648 + case "try": {

649 + const fallthroughId =

650 + terminal.fallthrough !== null &&

651 + !this.cx.isScheduled(terminal.fallthrough)

652 + ? terminal.fallthrough

653 + : null;

654 + if (fallthroughId !== null) {

655 + const scheduleId = this.cx.schedule(fallthroughId, "if");

656 + scheduleIds.push(scheduleId);

657 + }

658 +

659 + const block = this.traverseBlock(

660 + this.cx.ir.blocks.get(terminal.block)!

661 + );

662 + const handler = this.traverseBlock(

663 + this.cx.ir.blocks.get(terminal.handler)!

664 + );

665 +

666 + this.cx.unscheduleAll(scheduleIds);

667 + blockValue.push({

668 + kind: "terminal",

669 + label: fallthroughId,

670 + terminal: {

671 + kind: "try",

672 + block,

673 + handler,

674 + id: terminal.id,

675 + },

676 + });

677 +

678 + if (fallthroughId !== null) {

679 + this.visitBlock(this.cx.ir.blocks.get(fallthroughId)!, blockValue);

680 + }

681 + break;

682 + }

683 case "unsupported": {

684 CompilerError.invariant(false, {

685 reason: "Unexpected unsupported terminal",

compiler/packages/babel-plugin-react-forget/src/ReactiveScopes/CodegenReactiveFunction.ts

@@ -515,6 +515,12 @@ function codegenTerminal(

515 case "label": {

516 return codegenBlock(cx, terminal.block);

517 }

518 + case "try": {

519 + return t.tryStatement(

520 + codegenBlock(cx, terminal.block),

521 + t.catchClause(null, codegenBlock(cx, terminal.handler))

522 + );

523 + }

524 default: {

525 assertExhaustive(

526 terminal,

compiler/packages/babel-plugin-react-forget/src/ReactiveScopes/FlattenReactiveLoops.ts

@@ -54,6 +54,7 @@ class Transform extends ReactiveFunctionTransform<boolean> {

54 break;

55 }

56 // Non-loop terminals passthrough is contextual, inherits the parent isWithinScope

57 + case "try":

58 case "label":

59 case "break":

60 case "continue":

compiler/packages/babel-plugin-react-forget/src/ReactiveScopes/PrintReactiveFunction.ts

@@ -276,6 +276,14 @@ function printTerminal(writer: Writer, terminal: ReactiveTerminal): void {

276 writer.writeLine("}");

277 break;

278 }

279 + case "try": {

280 + writer.writeLine(`[${terminal.id}] try {`);

281 + printReactiveInstructions(writer, terminal.block);

282 + writer.writeLine(`} catch {`);

283 + printReactiveInstructions(writer, terminal.handler);

284 + writer.writeLine("}");

285 + break;

286 + }

287 default:

288 assertExhaustive(terminal, `Unhandled terminal ${terminal}`);

289 }

compiler/packages/babel-plugin-react-forget/src/ReactiveScopes/PropagateScopeDependencies.ts

@@ -670,6 +670,11 @@ class PropagationVisitor extends ReactiveFunctionVisitor<Context> {

670 this.visitBlock(terminal.block, context);

671 break;

672 }

673 + case "try": {

674 + this.visitBlock(terminal.block, context);

675 + this.visitBlock(terminal.handler, context);

676 + break;

677 + }

678 default: {

679 assertExhaustive(

680 terminal,

compiler/packages/babel-plugin-react-forget/src/ReactiveScopes/visitors.ts

+10

@@ -151,6 +151,11 @@ export class ReactiveFunctionVisitor<TState = void> {

151 this.visitBlock(terminal.block, state);

152 break;

153 }

154 + case "try": {

155 + this.visitBlock(terminal.block, state);

156 + this.visitBlock(terminal.handler, state);

157 + break;

158 + }

159 default: {

160 assertExhaustive(

161 terminal,

@@ -361,6 +366,11 @@ export function mapTerminalBlocks(

366 terminal.block = fn(terminal.block);

367 break;

368 }

369 + case "try": {

370 + terminal.block = fn(terminal.block);

371 + terminal.handler = fn(terminal.handler);

372 + break;

373 + }

374 default: {

375 assertExhaustive(

376 terminal,

compiler/packages/babel-plugin-react-forget/src/Utils/VisualizeHIRMermaid.ts

@@ -139,6 +139,7 @@ function printTerminalLabel(terminal: Terminal): string {

139 buffer.push("Sequence");

140 break;

141 }

142 + case "try":

143 case "maybe-throw":

144 case "unsupported": {

145 break;

@@ -247,6 +248,7 @@ function printTerminalArrows(blockId: BlockId, terminal: Terminal): string {

248 buffer.push(printJumpArrow(blockId, terminal.fallthrough, "fallthrough"));

249 break;

250 }

251 + case "try":

252 case "maybe-throw":

253 case "throw":

254 case "return":