InferReactiveScopes considers all operands, incl terminals

compiler/forget/src/HIR/HIRTreeVisitor.ts

@@ -66,7 +66,9 @@ class Driver<TBlock, TValue, TItem, TCase> {
     switch (terminal.kind) {
       case "return": {
         const value =
-          terminal.value != null ? this.visitPlace(terminal.value) : null;
+          terminal.value != null
+            ? this.visitPlace(terminal.value, terminal.id)
+            : null;
         this.visitor.visitTerminalId(terminal.id);
         this.visitor.appendBlock(
           blockValue,
@@ -78,7 +80,7 @@ class Driver<TBlock, TValue, TItem, TCase> {
         break;
       }
       case "throw": {
-        const value = this.visitPlace(terminal.value);
+        const value = this.visitPlace(terminal.value, terminal.id);
         this.visitor.visitTerminalId(terminal.id);
         this.visitor.appendBlock(
           blockValue,
@@ -90,7 +92,7 @@ class Driver<TBlock, TValue, TItem, TCase> {
         break;
       }
       case "if": {
-        const test = this.visitPlace(terminal.test);
+        const test = this.visitPlace(terminal.test, terminal.id);
         const fallthroughId =
           terminal.fallthrough !== null &&
           !this.cx.isScheduled(terminal.fallthrough)
@@ -152,7 +154,7 @@ class Driver<TBlock, TValue, TItem, TCase> {
         break;
       }
       case "switch": {
-        const test = this.visitPlace(terminal.test);
+        const test = this.visitPlace(terminal.test, terminal.id);
         const fallthroughId =
           terminal.fallthrough !== null &&
           !this.cx.isScheduled(terminal.fallthrough)
@@ -166,7 +168,10 @@ class Driver<TBlock, TValue, TItem, TCase> {
         this.visitor.visitTerminalId(terminal.id);
         const cases: Array<TCase> = [];
         [...terminal.cases].reverse().forEach((case_, index) => {
-          const test = case_.test !== null ? this.visitPlace(case_.test) : null;
+          const test =
+            case_.test !== null
+              ? this.visitPlace(case_.test, terminal.id)
+              : null;
 
           let consequent;
           if (this.cx.isScheduled(case_.block)) {
@@ -241,7 +246,7 @@ class Driver<TBlock, TValue, TItem, TCase> {
         //   body.length === bodyLength,
         //   "Expected test to produce only temporaries"
         // );
-        const testValue = this.visitPlace(testTerminal.test);
+        const testValue = this.visitPlace(testTerminal.test, terminal.id);
         const fallthroughId =
           terminal.fallthrough !== null &&
           !this.cx.isScheduled(terminal.fallthrough)
@@ -391,13 +396,13 @@ class Driver<TBlock, TValue, TItem, TCase> {
   }
 
   visitInstr(instr: Instruction, blockValue: TBlock): void {
-    const value = this.visitor.visitValue(instr.value);
+    const value = this.visitor.visitValue(instr.value, instr.id);
     const item = this.visitor.visitInstruction(instr, value);
     this.visitor.appendBlock(blockValue, item);
   }
 
-  visitPlace(place: Place): TValue {
-    return this.visitor.visitValue(place);
+  visitPlace(place: Place, id: InstructionId): TValue {
+    return this.visitor.visitValue(place, id);
   }
 }
 
@@ -642,7 +647,7 @@ export interface Visitor<TBlock, TValue, TItem, TCase> {
    * Convert an InstructionValue into the visitor's own representation
    * of a value.
    */
-  visitValue(value: InstructionValue): TValue;
+  visitValue(value: InstructionValue, id: InstructionId): TValue;
 
   /**
    * Convert an Instruction into the visitor's own representation of

compiler/forget/src/HIR/InferReactiveScopes.ts

@@ -17,7 +17,10 @@ import {
   ScopeId,
 } from "./HIR";
 import { BlockTerminal, Visitor, visitTree } from "./HIRTreeVisitor";
-import { eachInstructionOperand } from "./visitors";
+import {
+  eachInstructionOperand,
+  eachInstructionValueOperand,
+} from "./visitors";
 
 /**
  * This is a second (final) stage of constructing reactive scopes. Prior to this pass,
@@ -249,13 +252,28 @@ class MergeOverlappingReactiveScopesVisitor
   enterBlock(): void {
     this.scopes.push(new BlockScope());
   }
-  visitValue(value: InstructionValue): void {}
-  visitInstruction(instruction: Instruction, value: void): void {
-    const scope = getInstructionScope(instruction);
-    if (scope !== null && instruction.id < scope.range.end) {
-      this.visitScope(scope);
+  visitValue(value: InstructionValue, id: InstructionId): void {
+    this.visitId(id);
+    for (const operand of eachInstructionValueOperand(value)) {
+      if (
+        operand.identifier.scope !== null &&
+        id >= operand.identifier.scope.range.start &&
+        id < operand.identifier.scope.range.end
+      ) {
+        this.visitScope(operand.identifier.scope);
+      }
     }
+  }
+  visitInstruction(instruction: Instruction, value: void): void {
     this.visitId(instruction.id);
+    if (
+      instruction.lvalue !== null &&
+      instruction.lvalue.place.identifier.scope !== null &&
+      instruction.id >= instruction.lvalue.place.identifier.scope.range.start &&
+      instruction.id < instruction.lvalue.place.identifier.scope.range.end
+    ) {
+      this.visitScope(instruction.lvalue.place.identifier.scope);
+    }
   }
   visitTerminalId(id: InstructionId): void {
     this.visitId(id);

compiler/forget/src/HIR/visitors.ts

@@ -10,13 +10,18 @@ import {
   BasicBlock,
   BlockId,
   Instruction,
+  InstructionValue,
   makeInstructionId,
   Place,
   Terminal,
 } from "./HIR";
 
 export function* eachInstructionOperand(instr: Instruction): Iterable<Place> {
-  const instrValue = instr.value;
+  yield* eachInstructionValueOperand(instr.value);
+}
+export function* eachInstructionValueOperand(
+  instrValue: InstructionValue
+): Iterable<Place> {
   switch (instrValue.kind) {
     case "NewExpression":
     case "CallExpression": {

compiler/forget/src/__tests__/fixtures/hir/extend-scopes-if.expect.md

@@ -33,8 +33,8 @@ bb4:
   [4] If (read c$9) then:bb6 else:bb1
 bb6:
   predecessor blocks: bb4
-  [5] Const mutate $11_@0[1:8] = 0
-  [6] Call mutate x$10_@0.push(read $11_@0)
+  [5] Const mutate $11_@1 = 0
+  [6] Call mutate x$10_@0.push(read $11_@1)
   [7] Goto bb1
 bb1:
   predecessor blocks: bb6 bb4 bb2 bb0
@@ -67,8 +67,8 @@ flowchart TB
   end
   subgraph bb6
     bb6_instrs["
-      [5] Const mutate $11_@0[1:8] = 0
-      [6] Call mutate x$10_@0.push(read $11_@0)
+      [5] Const mutate $11_@1 = 0
+      [6] Call mutate x$10_@0.push(read $11_@1)
     "]
     bb6_instrs --> bb6_terminal(["Goto"])
   end

compiler/forget/src/__tests__/fixtures/hir/overlapping-scopes-interleaved-by-terminal.expect.md

@@ -0,0 +1,72 @@
+
+## Input
+
+```javascript
+function foo(a, b, c) {
+  const x = [];
+  const y = [];
+
+  if (x) {
+  }
+
+  y.push(a);
+  x.push(b);
+}
+
+```
+
+## HIR
+
+```
+bb0:
+  [1] Const mutate x$9_@0[1:6] = Array []
+  [2] Const mutate y$10_@0[1:6] = Array []
+  [3] If (read x$9_@0) then:bb1 else:bb1
+bb1:
+  predecessor blocks: bb0
+  [4] Call mutate y$10_@0.push(read a$6)
+  [5] Call mutate x$9_@0.push(read b$7)
+  [6] Return
+```
+
+### CFG
+
+```mermaid
+flowchart TB
+  %% Basic Blocks
+  subgraph bb0
+    bb0_instrs["
+      [1] Const mutate x$9_@0[1:6] = Array []
+      [2] Const mutate y$10_@0[1:6] = Array []
+    "]
+    bb0_instrs --> bb0_terminal(["If (read x$9_@0)"])
+  end
+  subgraph bb1
+    bb1_instrs["
+      [4] Call mutate y$10_@0.push(read a$6)
+      [5] Call mutate x$9_@0.push(read b$7)
+    "]
+    bb1_instrs --> bb1_terminal(["Return"])
+  end
+
+  %% Jumps
+  bb0_terminal -- "then" --> bb1
+  bb0_terminal -- "else" --> bb1
+
+```
+
+## Code
+
+```javascript
+function foo$0(a$1, b$2, c$3) {
+  const x$4 = [];
+  const y$5 = [];
+  bb1: if (x$4) {
+  }
+
+  y$5.push(a$1);
+  x$4.push(b$2);
+}
+
+```
+      

compiler/forget/src/__tests__/fixtures/hir/overlapping-scopes-interleaved-by-terminal.js

@@ -0,0 +1,10 @@
+function foo(a, b, c) {
+  const x = [];
+  const y = [];
+
+  if (x) {
+  }
+
+  y.push(a);
+  x.push(b);
+}

compiler/forget/src/__tests__/fixtures/hir/overlapping-scopes-shadowing-within-block.expect.md

@@ -34,8 +34,8 @@ bb4:
 bb3:
   predecessor blocks: bb4 bb2
   [7] Const mutate $13_@2 = "div"
-  [8] Const mutate $15_@0[1:11] = JSX <read $13_@2>{freeze y$12_@1}</read $13_@2>
-  [9] Call mutate x$11_@0.push(read $15_@0)
+  [8] Const mutate $15_@3 = JSX <read $13_@2>{freeze y$12_@1}</read $13_@2>
+  [9] Call mutate x$11_@0.push(read $15_@3)
   [10] Goto bb1
 bb1:
   predecessor blocks: bb3 bb0
@@ -68,8 +68,8 @@ flowchart TB
   subgraph bb3
     bb3_instrs["
       [7] Const mutate $13_@2 = 'div'
-      [8] Const mutate $15_@0[1:11] = JSX <read $13_@2>{freeze y$12_@1}</read $13_@2>
-      [9] Call mutate x$11_@0.push(read $15_@0)
+      [8] Const mutate $15_@3 = JSX <read $13_@2>{freeze y$12_@1}</read $13_@2>
+      [9] Call mutate x$11_@0.push(read $15_@3)
     "]
     bb3_instrs --> bb3_terminal(["Goto"])
   end

compiler/forget/src/__tests__/fixtures/hir/ssa-shadowing.expect.md

@@ -47,7 +47,7 @@ function log$0() {}
 
 ```
 bb0:
-  [1] Let mutate str$6_@2[0:9] = ""
+  [1] Let mutate str$6_@0[1:8] = ""
   [2] If (read cond$5) then:bb2 else:bb3
 bb2:
   predecessor blocks: bb0
@@ -56,12 +56,12 @@ bb2:
   [5] Goto bb1
 bb3:
   predecessor blocks: bb0
-  [6] Reassign mutate str$8_@2[0:9] = "fallthrough test"
+  [6] Reassign mutate str$8_@0[1:8] = "fallthrough test"
   [7] Goto bb1
 bb1:
   predecessor blocks: bb2 bb3
-  str$10_@2[0:9]: phi(bb2: str$6_@2, bb3: str$8_@2)
-  [8] Call mutate log$4_@2(read str$10_@2)
+  str$10_@0[1:8]: phi(bb2: str$6_@0, bb3: str$8_@0)
+  [8] Call mutate log$4_@2(read str$10_@0)
   [9] Return
 ```
 
@@ -72,7 +72,7 @@ flowchart TB
   %% Basic Blocks
   subgraph bb0
     bb0_instrs["
-      [1] Let mutate str$6_@2[0:9] = ''
+      [1] Let mutate str$6_@0[1:8] = ''
     "]
     bb0_instrs --> bb0_terminal(["If (read cond$5)"])
   end
@@ -85,13 +85,13 @@ flowchart TB
   end
   subgraph bb3
     bb3_instrs["
-      [6] Reassign mutate str$8_@2[0:9] = 'fallthrough test'
+      [6] Reassign mutate str$8_@0[1:8] = 'fallthrough test'
     "]
     bb3_instrs --> bb3_terminal(["Goto"])
   end
   subgraph bb1
     bb1_instrs["
-      [8] Call mutate log$4_@2(read str$10_@2)
+      [8] Call mutate log$4_@2(read str$10_@0)
     "]
     bb1_instrs --> bb1_terminal(["Return"])
   end

compiler/forget/src/__tests__/fixtures/hir/ssa-switch.expect.md

@@ -39,23 +39,23 @@ bb0:
     Default: bb2
 bb5:
   predecessor blocks: bb0
-  [7] Const mutate $15_@6[7:17] = 1
-  [8] Reassign mutate x$16_@6[7:17] = Binary read x$10_@0 + read $15_@6
+  [7] Const mutate $15_@5 = 1
+  [8] Reassign mutate x$16_@6[8:17] = Binary read x$10_@0 + read $15_@5
   [9] Goto bb1
 bb3:
   predecessor blocks: bb0
-  [10] Const mutate $17_@6[7:17] = 2
-  [11] Reassign mutate x$18_@6[7:17] = Binary read x$10_@0 + read $17_@6
+  [10] Const mutate $17_@7 = 2
+  [11] Reassign mutate x$18_@6[8:17] = Binary read x$10_@0 + read $17_@7
   [12] Goto bb1
 bb2:
   predecessor blocks: bb0
   [13] Const mutate $19_@8 = 3
-  [14] Reassign mutate x$20_@6[7:17] = Binary read x$10_@0 + read $19_@8
+  [14] Reassign mutate x$20_@6[8:17] = Binary read x$10_@0 + read $19_@8
   [15] Goto bb1
 bb1:
   predecessor blocks: bb5 bb3 bb2
-  x$21_@6[7:17]: phi(bb5: x$16_@6, bb3: x$18_@6, bb2: x$20_@6)
-  [16] Let mutate y$22_@6[7:17] = read x$21_@6
+  x$21_@6[8:17]: phi(bb5: x$16_@6, bb3: x$18_@6, bb2: x$20_@6)
+  [16] Let mutate y$22_@6[8:17] = read x$21_@6
   [17] Return
 ```
 
@@ -76,28 +76,28 @@ flowchart TB
   end
   subgraph bb5
     bb5_instrs["
-      [7] Const mutate $15_@6[7:17] = 1
-      [8] Reassign mutate x$16_@6[7:17] = Binary read x$10_@0 + read $15_@6
+      [7] Const mutate $15_@5 = 1
+      [8] Reassign mutate x$16_@6[8:17] = Binary read x$10_@0 + read $15_@5
     "]
     bb5_instrs --> bb5_terminal(["Goto"])
   end
   subgraph bb3
     bb3_instrs["
-      [10] Const mutate $17_@6[7:17] = 2
-      [11] Reassign mutate x$18_@6[7:17] = Binary read x$10_@0 + read $17_@6
+      [10] Const mutate $17_@7 = 2
+      [11] Reassign mutate x$18_@6[8:17] = Binary read x$10_@0 + read $17_@7
     "]
     bb3_instrs --> bb3_terminal(["Goto"])
   end
   subgraph bb2
     bb2_instrs["
       [13] Const mutate $19_@8 = 3
-      [14] Reassign mutate x$20_@6[7:17] = Binary read x$10_@0 + read $19_@8
+      [14] Reassign mutate x$20_@6[8:17] = Binary read x$10_@0 + read $19_@8
     "]
     bb2_instrs --> bb2_terminal(["Goto"])
   end
   subgraph bb1
     bb1_instrs["
-      [16] Let mutate y$22_@6[7:17] = read x$21_@6
+      [16] Let mutate y$22_@6[8:17] = read x$21_@6
     "]
     bb1_instrs --> bb1_terminal(["Return"])
   end

compiler/forget/src/__tests__/fixtures/hir/ssa-while.expect.md

@@ -27,8 +27,8 @@ bb1:
   [5] If (read $8_@2) then:bb3 else:bb2
 bb3:
   predecessor blocks: bb1
-  [6] Const mutate $9_@0[0:9] = 1
-  [7] Reassign mutate x$10_@0[0:9] = Binary read x$7_@0 + read $9_@0
+  [6] Const mutate $9_@3 = 1
+  [7] Reassign mutate x$10_@0[0:9] = Binary read x$7_@0 + read $9_@3
   [8] Goto(Continue) bb1
 bb2:
   predecessor blocks: bb1
@@ -55,8 +55,8 @@ flowchart TB
   end
   subgraph bb3
     bb3_instrs["
-      [6] Const mutate $9_@0[0:9] = 1
-      [7] Reassign mutate x$10_@0[0:9] = Binary read x$7_@0 + read $9_@0
+      [6] Const mutate $9_@3 = 1
+      [7] Reassign mutate x$10_@0[0:9] = Binary read x$7_@0 + read $9_@3
     "]
     bb3_instrs --> bb3_terminal(["Goto"])
   end