From afdd2cb9104254ded6b507bfbbe5ada541e8be9d Mon Sep 17 00:00:00 2001
From: Sathya Gunasekaran <gsathya.ceg@gmail.com>
Date: Wed, 21 Dec 2022 12:04:01 +0000
Subject: [PATCH] [hir] Add Effect.Store

Effect.Store is exactly like Effect.Mutate, the only difference is that Store
aliases one into a another value.

There is no practical difference between Effect.Mutate and Effect.Store
currently.
---
 compiler/forget/src/HIR/HIR.ts                   |  2 ++
 compiler/forget/src/HIR/InferMutableLifetimes.ts |  1 +
 compiler/forget/src/HIR/InferReferenceEffects.ts | 16 ++++++++++++++--
 .../alias-nested-member-path-mutate.expect.md    |  8 ++++----
 .../hir/alias-nested-member-path.expect.md       |  8 ++++----
 .../fixtures/hir/assignment-variations.expect.md |  4 ++--
 ...dependently-memoize-object-property.expect.md |  4 ++--
 .../hir/mutable-lifetime-with-aliasing.expect.md |  4 ++--
 .../fixtures/hir/property-assignment.expect.md   |  4 ++--
 .../hir/reactive-scope-grouping.expect.md        |  4 ++--
 .../ssa-property-alias-alias-mutate-if.expect.md |  8 ++++----
 .../fixtures/hir/ssa-property-alias-if.expect.md |  8 ++++----
 .../hir/ssa-property-alias-mutate-if.expect.md   |  8 ++++----
 ...ssa-property-alias-mutate-inside-if.expect.md |  8 ++++----
 .../hir/ssa-property-alias-mutate.expect.md      |  4 ++--
 .../fixtures/hir/ssa-property-mutate-2.expect.md |  4 ++--
 .../hir/ssa-property-mutate-alias.expect.md      |  4 ++--
 .../fixtures/hir/ssa-property-mutate.expect.md   |  4 ++--
 .../fixtures/hir/ssa-property.expect.md          |  4 ++--
 .../hir/transitive-alias-fields.expect.md        | 12 ++++++------
 .../fixtures/hir/type-test-field-store.expect.md |  4 ++--
 .../fixtures/hir/type-test-polymorphic.expect.md |  8 ++++----
 22 files changed, 73 insertions(+), 58 deletions(-)

diff --git a/compiler/forget/src/HIR/HIR.ts b/compiler/forget/src/HIR/HIR.ts
index 35d69199c7..36c5990da0 100644
--- a/compiler/forget/src/HIR/HIR.ts
+++ b/compiler/forget/src/HIR/HIR.ts
@@ -376,6 +376,8 @@ export enum Effect {
   Read = "read",
   // This reference may write to (mutate) the value
   Mutate = "mutate",
+  // This reference may alias to (mutate) the value
+  Store = "store",
 }
 
 export type ReactiveScope = {
diff --git a/compiler/forget/src/HIR/InferMutableLifetimes.ts b/compiler/forget/src/HIR/InferMutableLifetimes.ts
index 881ad9ea4a..a0d2b7a7b3 100644
--- a/compiler/forget/src/HIR/InferMutableLifetimes.ts
+++ b/compiler/forget/src/HIR/InferMutableLifetimes.ts
@@ -72,6 +72,7 @@ function inferPlace(place: Place, instr: Instruction) {
     case Effect.Read:
     case Effect.Freeze:
       return;
+    case Effect.Store:
     case Effect.Mutate: {
       place.identifier.mutableRange.end = makeInstructionId(instr.id + 1);
       return;
diff --git a/compiler/forget/src/HIR/InferReferenceEffects.ts b/compiler/forget/src/HIR/InferReferenceEffects.ts
index d3481aaba9..82f83a23e9 100644
--- a/compiler/forget/src/HIR/InferReferenceEffects.ts
+++ b/compiler/forget/src/HIR/InferReferenceEffects.ts
@@ -270,6 +270,18 @@ class Environment {
         }
         break;
       }
+      case Effect.Store: {
+        // TODO(gsn): Uncomment the invariant once
+        // https://github.com/facebook/react-forget/pull/908#discussion_r1054294337
+        // is fixed.
+        //
+        // invariant(
+        //   valueKind === ValueKind.Mutable,
+        //   `expected valueKind to be 'Mutable' but found to be '${valueKind}'`
+        // );
+        effect = Effect.Store;
+        break;
+      }
       case Effect.Read: {
         effect = Effect.Read;
         break;
@@ -575,10 +587,10 @@ function inferBlock(env: Environment, block: BasicBlock) {
             env.define(lvalue.place, instrValue);
           } else if (instrValue.memberPath === null) {
             // no-op: `a.b.c = d`
-            env.reference(lvalue.place, Effect.Mutate);
+            env.reference(lvalue.place, Effect.Store);
           } else {
             // no-op: `a.b.c = d.e.f`
-            env.reference(lvalue.place, Effect.Mutate);
+            env.reference(lvalue.place, Effect.Store);
           }
         }
         continue;
diff --git a/compiler/forget/src/__tests__/fixtures/hir/alias-nested-member-path-mutate.expect.md b/compiler/forget/src/__tests__/fixtures/hir/alias-nested-member-path-mutate.expect.md
index bec0c01fec..82990ba470 100644
--- a/compiler/forget/src/__tests__/fixtures/hir/alias-nested-member-path-mutate.expect.md
+++ b/compiler/forget/src/__tests__/fixtures/hir/alias-nested-member-path-mutate.expect.md
@@ -19,9 +19,9 @@ function component() {
 bb0:
   [1] Const mutate z$5_@0[1:7] = Array []
   [2] Const mutate y$6_@0:TObject[1:7] = Object {  }
-  [3] Reassign mutate y$6_@0.z[1:7] = read z$5_@0
+  [3] Reassign store y$6_@0.z[1:7] = read z$5_@0
   [4] Const mutate x$7_@0:TObject[1:7] = Object {  }
-  [5] Reassign mutate x$7_@0.y[1:7] = read y$6_@0:TObject
+  [5] Reassign store x$7_@0.y[1:7] = read y$6_@0:TObject
   [6] Call mutate mutate$4:TFunction(mutate x$7_@0.y.z)
   [7] Return
 ```
@@ -33,9 +33,9 @@ function component(
 ) {
   [1] Const mutate z$5_@0[1:7] = Array []
   [2] Const mutate y$6_@0:TObject[1:7] = Object {  }
-  [3] Reassign mutate y$6_@0.z[1:7] = read z$5_@0
+  [3] Reassign store y$6_@0.z[1:7] = read z$5_@0
   [4] Const mutate x$7_@0:TObject[1:7] = Object {  }
-  [5] Reassign mutate x$7_@0.y[1:7] = read y$6_@0:TObject
+  [5] Reassign store x$7_@0.y[1:7] = read y$6_@0:TObject
   [6] Call mutate mutate$4:TFunction(mutate x$7_@0.y.z)
   return
 }
diff --git a/compiler/forget/src/__tests__/fixtures/hir/alias-nested-member-path.expect.md b/compiler/forget/src/__tests__/fixtures/hir/alias-nested-member-path.expect.md
index f503b73597..fcb1cae51e 100644
--- a/compiler/forget/src/__tests__/fixtures/hir/alias-nested-member-path.expect.md
+++ b/compiler/forget/src/__tests__/fixtures/hir/alias-nested-member-path.expect.md
@@ -19,9 +19,9 @@ function component() {
 bb0:
   [1] Const mutate z$4_@0 = Array []
   [2] Const mutate y$5_@1:TObject[2:4] = Object {  }
-  [3] Reassign mutate y$5_@1.z[2:4] = read z$4_@0
+  [3] Reassign store y$5_@1.z[2:4] = read z$4_@0
   [4] Const mutate x$6_@2:TObject[4:6] = Object {  }
-  [5] Reassign mutate x$6_@2.y[4:6] = read y$5_@1:TObject
+  [5] Reassign store x$6_@2.y[4:6] = read y$5_@1:TObject
   [6] Return freeze x$6_@2:TObject
 ```
 
@@ -35,11 +35,11 @@ function component(
   }
   scope @1 [2:4] deps=[read z$4_@0] out=[y$5_@1] {
     [2] Const mutate y$5_@1:TObject[2:4] = Object {  }
-    [3] Reassign mutate y$5_@1.z[2:4] = read z$4_@0
+    [3] Reassign store y$5_@1.z[2:4] = read z$4_@0
   }
   scope @2 [4:6] deps=[read y$5_@1:TObject] out=[x$6_@2] {
     [4] Const mutate x$6_@2:TObject[4:6] = Object {  }
-    [5] Reassign mutate x$6_@2.y[4:6] = read y$5_@1:TObject
+    [5] Reassign store x$6_@2.y[4:6] = read y$5_@1:TObject
   }
   return freeze x$6_@2:TObject
 }
diff --git a/compiler/forget/src/__tests__/fixtures/hir/assignment-variations.expect.md b/compiler/forget/src/__tests__/fixtures/hir/assignment-variations.expect.md
index a65ad7961e..cf4fb1f48c 100644
--- a/compiler/forget/src/__tests__/fixtures/hir/assignment-variations.expect.md
+++ b/compiler/forget/src/__tests__/fixtures/hir/assignment-variations.expect.md
@@ -64,7 +64,7 @@ function f$0() {
 bb0:
   [1] Const mutate $6:TPrimitive = 1
   [2] Const mutate $7:TPrimitive = Binary read a$5_@0.b.c + read $6:TPrimitive
-  [3] Reassign read a$5_@0.b.c[0:6] = read $7:TPrimitive
+  [3] Reassign store a$5_@0.b.c[0:6] = read $7:TPrimitive
   [4] Const mutate $8:TPrimitive = 2
   [5] Reassign mutate a$5_@0.b.c[0:6] = Binary read a$5_@0.b.c * read $8:TPrimitive
   [6] Return
@@ -78,7 +78,7 @@ function g(
 ) {
   [1] Const mutate $6:TPrimitive = 1
   [2] Const mutate $7:TPrimitive = Binary read a$5_@0.b.c + read $6:TPrimitive
-  [3] Reassign read a$5_@0.b.c[0:6] = read $7:TPrimitive
+  [3] Reassign store a$5_@0.b.c[0:6] = read $7:TPrimitive
   [4] Const mutate $8:TPrimitive = 2
   [5] Reassign mutate a$5_@0.b.c[0:6] = Binary read a$5_@0.b.c * read $8:TPrimitive
   return
diff --git a/compiler/forget/src/__tests__/fixtures/hir/independently-memoize-object-property.expect.md b/compiler/forget/src/__tests__/fixtures/hir/independently-memoize-object-property.expect.md
index 825db2fe3d..16edfe5dcc 100644
--- a/compiler/forget/src/__tests__/fixtures/hir/independently-memoize-object-property.expect.md
+++ b/compiler/forget/src/__tests__/fixtures/hir/independently-memoize-object-property.expect.md
@@ -18,7 +18,7 @@ function foo(a, b, c) {
 bb0:
   [1] Const mutate x$9_@0:TObject[1:4] = Object { a: read a$6 }
   [2] Const mutate t6$10_@1 = Array [read b$7, read c$8]
-  [3] Reassign mutate x$9_@0.y[1:4] = read t6$10_@1
+  [3] Reassign store x$9_@0.y[1:4] = read t6$10_@1
   [4] Return freeze x$9_@0:TObject
 ```
 
@@ -35,7 +35,7 @@ function foo(
     scope @1 [2:3] deps=[read b$7, read c$8] out=[$10_@1] {
       [2] Const mutate $10_@1 = Array [read b$7, read c$8]
     }
-    [3] Reassign mutate x$9_@0.y[1:4] = read $10_@1
+    [3] Reassign store x$9_@0.y[1:4] = read $10_@1
   }
   return freeze x$9_@0:TObject
 }
diff --git a/compiler/forget/src/__tests__/fixtures/hir/mutable-lifetime-with-aliasing.expect.md b/compiler/forget/src/__tests__/fixtures/hir/mutable-lifetime-with-aliasing.expect.md
index d5c3b4d32b..8c77655861 100644
--- a/compiler/forget/src/__tests__/fixtures/hir/mutable-lifetime-with-aliasing.expect.md
+++ b/compiler/forget/src/__tests__/fixtures/hir/mutable-lifetime-with-aliasing.expect.md
@@ -69,7 +69,7 @@ bb0:
   [3] Const mutate c$13_@2:TObject = Object {  }
   [4] Const mutate d$14_@1:TObject[2:15] = Object { c: read c$13_@2:TObject }
   [5] Const mutate x$15_@1:TObject[2:15] = Object {  }
-  [6] Reassign mutate x$15_@1.b[2:15] = read b$12_@1
+  [6] Reassign store x$15_@1.b[2:15] = read b$12_@1
   [7] Const mutate y$16_@1[2:15] = Call mutate mutate$8:TFunction(mutate x$15_@1:TObject, mutate d$14_@1:TObject)
   [8] If (read a$11_@0:TObject) then:bb1 else:bb1 fallthrough=bb1
 bb1:
@@ -106,7 +106,7 @@ function Component(
   }
   [4] Const mutate d$14_@1:TObject[2:15] = Object { c: read c$13_@2:TObject }
   [5] Const mutate x$15_@1:TObject[2:15] = Object {  }
-  [6] Reassign mutate x$15_@1.b[2:15] = read b$12_@1
+  [6] Reassign store x$15_@1.b[2:15] = read b$12_@1
   [7] Const mutate y$16_@1[2:15] = Call mutate mutate$8:TFunction(mutate x$15_@1:TObject, mutate d$14_@1:TObject)
   if (read a$11_@0:TObject) {
   }
diff --git a/compiler/forget/src/__tests__/fixtures/hir/property-assignment.expect.md b/compiler/forget/src/__tests__/fixtures/hir/property-assignment.expect.md
index 52e4fd4fd8..0f844de5dc 100644
--- a/compiler/forget/src/__tests__/fixtures/hir/property-assignment.expect.md
+++ b/compiler/forget/src/__tests__/fixtures/hir/property-assignment.expect.md
@@ -19,7 +19,7 @@ function Component(props) {
 bb0:
   [1] Const mutate x$7_@0:TObject[1:6] = Object {  }
   [2] Const mutate y$8_@0[1:6] = Array []
-  [3] Reassign mutate x$7_@0.y[1:6] = read y$8_@0
+  [3] Reassign store x$7_@0.y[1:6] = read y$8_@0
   [4] Const mutate child$9_@0[1:6] = JSX <read Component$0 data={freeze y$8_@0} ></read Component$0>
   [5] Call mutate x$7_@0.y.push(read props$6.p0)
   [6] Const mutate t5$10_@1 = JSX <read Component$0 data={freeze x$7_@0:TObject} >{read child$9_@0}</read Component$0>
@@ -35,7 +35,7 @@ function Component(
   scope @0 [1:6] deps=[read props$6.p0] out=[x$7_@0, child$9_@0] {
     [1] Const mutate x$7_@0:TObject[1:6] = Object {  }
     [2] Const mutate y$8_@0[1:6] = Array []
-    [3] Reassign mutate x$7_@0.y[1:6] = read y$8_@0
+    [3] Reassign store x$7_@0.y[1:6] = read y$8_@0
     [4] Const mutate child$9_@0[1:6] = JSX <read Component$0 data={freeze y$8_@0} ></read Component$0>
     [5] Call mutate x$7_@0.y.push(read props$6.p0)
   }
diff --git a/compiler/forget/src/__tests__/fixtures/hir/reactive-scope-grouping.expect.md b/compiler/forget/src/__tests__/fixtures/hir/reactive-scope-grouping.expect.md
index 5e8e225b2c..67162e5f64 100644
--- a/compiler/forget/src/__tests__/fixtures/hir/reactive-scope-grouping.expect.md
+++ b/compiler/forget/src/__tests__/fixtures/hir/reactive-scope-grouping.expect.md
@@ -22,7 +22,7 @@ bb0:
   [2] Const mutate y$5_@1[2:5] = Array []
   [3] Const mutate z$6_@1:TObject[2:5] = Object {  }
   [4] Call mutate y$5_@1.push(mutate z$6_@1:TObject)
-  [5] Reassign mutate x$4_@0.y[1:6] = read y$5_@1
+  [5] Reassign store x$4_@0.y[1:6] = read y$5_@1
   [6] Return freeze x$4_@0:TObject
 ```
 
@@ -38,7 +38,7 @@ function foo(
       [3] Const mutate z$6_@1:TObject[2:5] = Object {  }
       [4] Call mutate y$5_@1.push(mutate z$6_@1:TObject)
     }
-    [5] Reassign mutate x$4_@0.y[1:6] = read y$5_@1
+    [5] Reassign store x$4_@0.y[1:6] = read y$5_@1
   }
   return freeze x$4_@0:TObject
 }
diff --git a/compiler/forget/src/__tests__/fixtures/hir/ssa-property-alias-alias-mutate-if.expect.md b/compiler/forget/src/__tests__/fixtures/hir/ssa-property-alias-alias-mutate-if.expect.md
index 7cecf3a318..7228cdecfb 100644
--- a/compiler/forget/src/__tests__/fixtures/hir/ssa-property-alias-alias-mutate-if.expect.md
+++ b/compiler/forget/src/__tests__/fixtures/hir/ssa-property-alias-alias-mutate-if.expect.md
@@ -28,12 +28,12 @@ bb0:
 bb2:
   predecessor blocks: bb0
   [4] Const mutate y$10_@0:TObject[1:11] = Object {  }
-  [5] Reassign mutate x$9_@0.y[1:11] = read y$10_@0:TObject
+  [5] Reassign store x$9_@0.y[1:11] = read y$10_@0:TObject
   [6] Goto bb1
 bb3:
   predecessor blocks: bb0
   [7] Const mutate z$11_@0:TObject[1:11] = Object {  }
-  [8] Reassign mutate x$9_@0.z[1:11] = read z$11_@0:TObject
+  [8] Reassign store x$9_@0.z[1:11] = read z$11_@0:TObject
   [9] Goto bb1
 bb1:
   predecessor blocks: bb2 bb3
@@ -52,10 +52,10 @@ function foo(
     [2] Const mutate x$9_@0:TObject[1:11] = read b$8_@0:TObject
     if (read a$7) {
       [4] Const mutate y$10_@0:TObject[1:11] = Object {  }
-      [5] Reassign mutate x$9_@0.y[1:11] = read y$10_@0:TObject
+      [5] Reassign store x$9_@0.y[1:11] = read y$10_@0:TObject
     } else {
       [7] Const mutate z$11_@0:TObject[1:11] = Object {  }
-      [8] Reassign mutate x$9_@0.z[1:11] = read z$11_@0:TObject
+      [8] Reassign store x$9_@0.z[1:11] = read z$11_@0:TObject
     }
     [10] Call mutate mutate$6:TFunction(mutate b$8_@0:TObject)
   }
diff --git a/compiler/forget/src/__tests__/fixtures/hir/ssa-property-alias-if.expect.md b/compiler/forget/src/__tests__/fixtures/hir/ssa-property-alias-if.expect.md
index 91677488f9..49ed7cf4aa 100644
--- a/compiler/forget/src/__tests__/fixtures/hir/ssa-property-alias-if.expect.md
+++ b/compiler/forget/src/__tests__/fixtures/hir/ssa-property-alias-if.expect.md
@@ -25,12 +25,12 @@ bb0:
 bb2:
   predecessor blocks: bb0
   [3] Const mutate y$7_@1:TObject = Object {  }
-  [4] Reassign mutate x$6_@0.y[1:9] = read y$7_@1:TObject
+  [4] Reassign store x$6_@0.y[1:9] = read y$7_@1:TObject
   [5] Goto bb1
 bb3:
   predecessor blocks: bb0
   [6] Const mutate z$8_@2:TObject = Object {  }
-  [7] Reassign mutate x$6_@0.z[1:9] = read z$8_@2:TObject
+  [7] Reassign store x$6_@0.z[1:9] = read z$8_@2:TObject
   [8] Goto bb1
 bb1:
   predecessor blocks: bb2 bb3
@@ -49,12 +49,12 @@ function foo(
       scope @1 [3:4] deps=[] out=[y$7_@1] {
         [3] Const mutate y$7_@1:TObject = Object {  }
       }
-      [4] Reassign mutate x$6_@0.y[1:9] = read y$7_@1:TObject
+      [4] Reassign store x$6_@0.y[1:9] = read y$7_@1:TObject
     } else {
       scope @2 [6:7] deps=[] out=[z$8_@2] {
         [6] Const mutate z$8_@2:TObject = Object {  }
       }
-      [7] Reassign mutate x$6_@0.z[1:9] = read z$8_@2:TObject
+      [7] Reassign store x$6_@0.z[1:9] = read z$8_@2:TObject
     }
   }
   return freeze x$6_@0:TObject
diff --git a/compiler/forget/src/__tests__/fixtures/hir/ssa-property-alias-mutate-if.expect.md b/compiler/forget/src/__tests__/fixtures/hir/ssa-property-alias-mutate-if.expect.md
index 8f33db2205..9f99a2eced 100644
--- a/compiler/forget/src/__tests__/fixtures/hir/ssa-property-alias-mutate-if.expect.md
+++ b/compiler/forget/src/__tests__/fixtures/hir/ssa-property-alias-mutate-if.expect.md
@@ -26,12 +26,12 @@ bb0:
 bb2:
   predecessor blocks: bb0
   [3] Const mutate y$8_@0:TObject[1:10] = Object {  }
-  [4] Reassign mutate x$7_@0.y[1:10] = read y$8_@0:TObject
+  [4] Reassign store x$7_@0.y[1:10] = read y$8_@0:TObject
   [5] Goto bb1
 bb3:
   predecessor blocks: bb0
   [6] Const mutate z$9_@0:TObject[1:10] = Object {  }
-  [7] Reassign mutate x$7_@0.z[1:10] = read z$9_@0:TObject
+  [7] Reassign store x$7_@0.z[1:10] = read z$9_@0:TObject
   [8] Goto bb1
 bb1:
   predecessor blocks: bb2 bb3
@@ -49,10 +49,10 @@ function foo(
     [1] Const mutate x$7_@0:TObject[1:10] = Object {  }
     if (read a$6) {
       [3] Const mutate y$8_@0:TObject[1:10] = Object {  }
-      [4] Reassign mutate x$7_@0.y[1:10] = read y$8_@0:TObject
+      [4] Reassign store x$7_@0.y[1:10] = read y$8_@0:TObject
     } else {
       [6] Const mutate z$9_@0:TObject[1:10] = Object {  }
-      [7] Reassign mutate x$7_@0.z[1:10] = read z$9_@0:TObject
+      [7] Reassign store x$7_@0.z[1:10] = read z$9_@0:TObject
     }
     [9] Call mutate mutate$5:TFunction(mutate x$7_@0:TObject)
   }
diff --git a/compiler/forget/src/__tests__/fixtures/hir/ssa-property-alias-mutate-inside-if.expect.md b/compiler/forget/src/__tests__/fixtures/hir/ssa-property-alias-mutate-inside-if.expect.md
index f47e963968..59d1fe7c91 100644
--- a/compiler/forget/src/__tests__/fixtures/hir/ssa-property-alias-mutate-inside-if.expect.md
+++ b/compiler/forget/src/__tests__/fixtures/hir/ssa-property-alias-mutate-inside-if.expect.md
@@ -26,13 +26,13 @@ bb0:
 bb2:
   predecessor blocks: bb0
   [3] Const mutate y$8_@0:TObject[1:10] = Object {  }
-  [4] Reassign mutate x$7_@0.y[1:10] = read y$8_@0:TObject
+  [4] Reassign store x$7_@0.y[1:10] = read y$8_@0:TObject
   [5] Call mutate mutate$4:TFunction(mutate y$8_@0:TObject)
   [6] Goto bb1
 bb3:
   predecessor blocks: bb0
   [7] Const mutate z$9_@1:TObject = Object {  }
-  [8] Reassign mutate x$7_@0.z[1:10] = read z$9_@1:TObject
+  [8] Reassign store x$7_@0.z[1:10] = read z$9_@1:TObject
   [9] Goto bb1
 bb1:
   predecessor blocks: bb2 bb3
@@ -49,13 +49,13 @@ function foo(
     [1] Const mutate x$7_@0:TObject[1:10] = Object {  }
     if (read a$6) {
       [3] Const mutate y$8_@0:TObject[1:10] = Object {  }
-      [4] Reassign mutate x$7_@0.y[1:10] = read y$8_@0:TObject
+      [4] Reassign store x$7_@0.y[1:10] = read y$8_@0:TObject
       [5] Call mutate mutate$4:TFunction(mutate y$8_@0:TObject)
     } else {
       scope @1 [7:8] deps=[] out=[z$9_@1] {
         [7] Const mutate z$9_@1:TObject = Object {  }
       }
-      [8] Reassign mutate x$7_@0.z[1:10] = read z$9_@1:TObject
+      [8] Reassign store x$7_@0.z[1:10] = read z$9_@1:TObject
     }
   }
   return freeze x$7_@0:TObject
diff --git a/compiler/forget/src/__tests__/fixtures/hir/ssa-property-alias-mutate.expect.md b/compiler/forget/src/__tests__/fixtures/hir/ssa-property-alias-mutate.expect.md
index b178687f5f..edf61fa7d9 100644
--- a/compiler/forget/src/__tests__/fixtures/hir/ssa-property-alias-mutate.expect.md
+++ b/compiler/forget/src/__tests__/fixtures/hir/ssa-property-alias-mutate.expect.md
@@ -22,7 +22,7 @@ bb0:
   [1] Const mutate a$5_@0:TObject[1:6] = Object {  }
   [2] Const mutate x$6_@0:TObject[1:6] = read a$5_@0:TObject
   [3] Const mutate y$7_@0:TObject[1:6] = Object {  }
-  [4] Reassign mutate y$7_@0.x[1:6] = read x$6_@0:TObject
+  [4] Reassign store y$7_@0.x[1:6] = read x$6_@0:TObject
   [5] Call mutate mutate$4:TFunction(mutate a$5_@0:TObject)
   [6] Return freeze y$7_@0:TObject
 ```
@@ -36,7 +36,7 @@ function foo(
     [1] Const mutate a$5_@0:TObject[1:6] = Object {  }
     [2] Const mutate x$6_@0:TObject[1:6] = read a$5_@0:TObject
     [3] Const mutate y$7_@0:TObject[1:6] = Object {  }
-    [4] Reassign mutate y$7_@0.x[1:6] = read x$6_@0:TObject
+    [4] Reassign store y$7_@0.x[1:6] = read x$6_@0:TObject
     [5] Call mutate mutate$4:TFunction(mutate a$5_@0:TObject)
   }
   return freeze y$7_@0:TObject
diff --git a/compiler/forget/src/__tests__/fixtures/hir/ssa-property-mutate-2.expect.md b/compiler/forget/src/__tests__/fixtures/hir/ssa-property-mutate-2.expect.md
index 4b80c3bdd3..bc9fb05665 100644
--- a/compiler/forget/src/__tests__/fixtures/hir/ssa-property-mutate-2.expect.md
+++ b/compiler/forget/src/__tests__/fixtures/hir/ssa-property-mutate-2.expect.md
@@ -18,7 +18,7 @@ function foo() {
 bb0:
   [1] Const mutate x$4_@0[1:5] = Array []
   [2] Const mutate y$5_@0:TObject[1:5] = Object {  }
-  [3] Reassign mutate y$5_@0.x[1:5] = read x$4_@0
+  [3] Reassign store y$5_@0.x[1:5] = read x$4_@0
   [4] Call mutate mutate$3:TFunction(mutate x$4_@0)
   [5] Return freeze y$5_@0:TObject
 ```
@@ -31,7 +31,7 @@ function foo(
   scope @0 [1:5] deps=[] out=[y$5_@0] {
     [1] Const mutate x$4_@0[1:5] = Array []
     [2] Const mutate y$5_@0:TObject[1:5] = Object {  }
-    [3] Reassign mutate y$5_@0.x[1:5] = read x$4_@0
+    [3] Reassign store y$5_@0.x[1:5] = read x$4_@0
     [4] Call mutate mutate$3:TFunction(mutate x$4_@0)
   }
   return freeze y$5_@0:TObject
diff --git a/compiler/forget/src/__tests__/fixtures/hir/ssa-property-mutate-alias.expect.md b/compiler/forget/src/__tests__/fixtures/hir/ssa-property-mutate-alias.expect.md
index caf3562f38..7338e9aa0a 100644
--- a/compiler/forget/src/__tests__/fixtures/hir/ssa-property-mutate-alias.expect.md
+++ b/compiler/forget/src/__tests__/fixtures/hir/ssa-property-mutate-alias.expect.md
@@ -22,7 +22,7 @@ bb0:
   [1] Const mutate a$5_@0:TObject[1:6] = Object {  }
   [2] Const mutate y$6_@0:TObject[1:6] = read a$5_@0:TObject
   [3] Const mutate x$7_@0[1:6] = Array []
-  [4] Reassign mutate y$6_@0.x[1:6] = read x$7_@0
+  [4] Reassign store y$6_@0.x[1:6] = read x$7_@0
   [5] Call mutate mutate$4:TFunction(mutate a$5_@0:TObject)
   [6] Return freeze y$6_@0:TObject
 ```
@@ -36,7 +36,7 @@ function foo(
     [1] Const mutate a$5_@0:TObject[1:6] = Object {  }
     [2] Const mutate y$6_@0:TObject[1:6] = read a$5_@0:TObject
     [3] Const mutate x$7_@0[1:6] = Array []
-    [4] Reassign mutate y$6_@0.x[1:6] = read x$7_@0
+    [4] Reassign store y$6_@0.x[1:6] = read x$7_@0
     [5] Call mutate mutate$4:TFunction(mutate a$5_@0:TObject)
   }
   return freeze y$6_@0:TObject
diff --git a/compiler/forget/src/__tests__/fixtures/hir/ssa-property-mutate.expect.md b/compiler/forget/src/__tests__/fixtures/hir/ssa-property-mutate.expect.md
index 4495bced5a..a34a301b10 100644
--- a/compiler/forget/src/__tests__/fixtures/hir/ssa-property-mutate.expect.md
+++ b/compiler/forget/src/__tests__/fixtures/hir/ssa-property-mutate.expect.md
@@ -18,7 +18,7 @@ function foo() {
 bb0:
   [1] Const mutate x$4_@0[1:5] = Array []
   [2] Const mutate y$5_@0:TObject[1:5] = Object {  }
-  [3] Reassign mutate y$5_@0.x[1:5] = read x$4_@0
+  [3] Reassign store y$5_@0.x[1:5] = read x$4_@0
   [4] Call mutate mutate$3:TFunction(mutate y$5_@0:TObject)
   [5] Return freeze y$5_@0:TObject
 ```
@@ -31,7 +31,7 @@ function foo(
   scope @0 [1:5] deps=[] out=[y$5_@0] {
     [1] Const mutate x$4_@0[1:5] = Array []
     [2] Const mutate y$5_@0:TObject[1:5] = Object {  }
-    [3] Reassign mutate y$5_@0.x[1:5] = read x$4_@0
+    [3] Reassign store y$5_@0.x[1:5] = read x$4_@0
     [4] Call mutate mutate$3:TFunction(mutate y$5_@0:TObject)
   }
   return freeze y$5_@0:TObject
diff --git a/compiler/forget/src/__tests__/fixtures/hir/ssa-property.expect.md b/compiler/forget/src/__tests__/fixtures/hir/ssa-property.expect.md
index 7cd141438a..9d4989455e 100644
--- a/compiler/forget/src/__tests__/fixtures/hir/ssa-property.expect.md
+++ b/compiler/forget/src/__tests__/fixtures/hir/ssa-property.expect.md
@@ -17,7 +17,7 @@ function foo() {
 bb0:
   [1] Const mutate x$3_@0 = Array []
   [2] Const mutate y$4_@1:TObject[2:4] = Object {  }
-  [3] Reassign mutate y$4_@1.x[2:4] = read x$3_@0
+  [3] Reassign store y$4_@1.x[2:4] = read x$3_@0
   [4] Return freeze y$4_@1:TObject
 ```
 
@@ -31,7 +31,7 @@ function foo(
   }
   scope @1 [2:4] deps=[read x$3_@0] out=[y$4_@1] {
     [2] Const mutate y$4_@1:TObject[2:4] = Object {  }
-    [3] Reassign mutate y$4_@1.x[2:4] = read x$3_@0
+    [3] Reassign store y$4_@1.x[2:4] = read x$3_@0
   }
   return freeze y$4_@1:TObject
 }
diff --git a/compiler/forget/src/__tests__/fixtures/hir/transitive-alias-fields.expect.md b/compiler/forget/src/__tests__/fixtures/hir/transitive-alias-fields.expect.md
index d82370f934..6d64e5d287 100644
--- a/compiler/forget/src/__tests__/fixtures/hir/transitive-alias-fields.expect.md
+++ b/compiler/forget/src/__tests__/fixtures/hir/transitive-alias-fields.expect.md
@@ -25,9 +25,9 @@ bb0:
   [2] Const mutate p$7_@0:TObject[1:9] = Object {  }
   [3] Const mutate q$8_@0:TObject[1:9] = Object {  }
   [4] Const mutate y$9_@0:TObject[1:9] = Object {  }
-  [5] Reassign mutate x$6_@0.y[1:9] = read y$9_@0:TObject
-  [6] Reassign mutate p$7_@0.y[1:9] = read x$6_@0.y
-  [7] Reassign mutate q$8_@0.y[1:9] = read p$7_@0.y
+  [5] Reassign store x$6_@0.y[1:9] = read y$9_@0:TObject
+  [6] Reassign store p$7_@0.y[1:9] = read x$6_@0.y
+  [7] Reassign store q$8_@0.y[1:9] = read p$7_@0.y
   [8] Call mutate mutate$5:TFunction(mutate q$8_@0:TObject)
   [9] Return
 ```
@@ -41,9 +41,9 @@ function component(
   [2] Const mutate p$7_@0:TObject[1:9] = Object {  }
   [3] Const mutate q$8_@0:TObject[1:9] = Object {  }
   [4] Const mutate y$9_@0:TObject[1:9] = Object {  }
-  [5] Reassign mutate x$6_@0.y[1:9] = read y$9_@0:TObject
-  [6] Reassign mutate p$7_@0.y[1:9] = read x$6_@0.y
-  [7] Reassign mutate q$8_@0.y[1:9] = read p$7_@0.y
+  [5] Reassign store x$6_@0.y[1:9] = read y$9_@0:TObject
+  [6] Reassign store p$7_@0.y[1:9] = read x$6_@0.y
+  [7] Reassign store q$8_@0.y[1:9] = read p$7_@0.y
   [8] Call mutate mutate$5:TFunction(mutate q$8_@0:TObject)
   return
 }
diff --git a/compiler/forget/src/__tests__/fixtures/hir/type-test-field-store.expect.md b/compiler/forget/src/__tests__/fixtures/hir/type-test-field-store.expect.md
index 3d95311bd0..405abdaa1d 100644
--- a/compiler/forget/src/__tests__/fixtures/hir/type-test-field-store.expect.md
+++ b/compiler/forget/src/__tests__/fixtures/hir/type-test-field-store.expect.md
@@ -17,7 +17,7 @@ function component() {
 bb0:
   [1] Const mutate x$4_@0:TObject[1:4] = Object {  }
   [2] Const mutate q$5_@1:TObject = Object {  }
-  [3] Reassign mutate x$4_@0.t[1:4] = read q$5_@1:TObject
+  [3] Reassign store x$4_@0.t[1:4] = read q$5_@1:TObject
   [4] Const mutate z$6:TObject = read x$4_@0.t
   [5] Return
 ```
@@ -32,7 +32,7 @@ function component(
     scope @1 [2:3] deps=[] out=[q$5_@1] {
       [2] Const mutate q$5_@1:TObject = Object {  }
     }
-    [3] Reassign mutate x$4_@0.t[1:4] = read q$5_@1:TObject
+    [3] Reassign store x$4_@0.t[1:4] = read q$5_@1:TObject
   }
   [4] Const mutate z$6:TObject = read x$4_@0.t
   return
diff --git a/compiler/forget/src/__tests__/fixtures/hir/type-test-polymorphic.expect.md b/compiler/forget/src/__tests__/fixtures/hir/type-test-polymorphic.expect.md
index 52fcdd7014..b60864b6ed 100644
--- a/compiler/forget/src/__tests__/fixtures/hir/type-test-polymorphic.expect.md
+++ b/compiler/forget/src/__tests__/fixtures/hir/type-test-polymorphic.expect.md
@@ -26,9 +26,9 @@ bb0:
   [2] Binary read p$7_@0:TPrimitive + read p$7_@0:TPrimitive
   [3] Const mutate o$8_@1:TObject = Object {  }
   [4] Const mutate x$9_@2:TObject[4:8] = Object {  }
-  [5] Reassign mutate x$9_@2.t[4:8] = read p$7_@0:TPrimitive
+  [5] Reassign store x$9_@2.t[4:8] = read p$7_@0:TPrimitive
   [6] Const mutate z$10_@2:TPrimitive[4:8] = read x$9_@2.t
-  [7] Reassign mutate x$9_@2.t[4:8] = read o$8_@1:TObject
+  [7] Reassign store x$9_@2.t[4:8] = read o$8_@1:TObject
   [8] Const mutate y$11:TPoly = read x$9_@2.t
   [9] Return
 ```
@@ -47,9 +47,9 @@ function component(
   }
   scope @2 [4:8] deps=[read p$7_@0:TPrimitive, read o$8_@1:TObject] out=[x$9_@2] {
     [4] Const mutate x$9_@2:TObject[4:8] = Object {  }
-    [5] Reassign mutate x$9_@2.t[4:8] = read p$7_@0:TPrimitive
+    [5] Reassign store x$9_@2.t[4:8] = read p$7_@0:TPrimitive
     [6] Const mutate z$10_@2:TPrimitive[4:8] = read x$9_@2.t
-    [7] Reassign mutate x$9_@2.t[4:8] = read o$8_@1:TObject
+    [7] Reassign store x$9_@2.t[4:8] = read o$8_@1:TObject
   }
   [8] Const mutate y$11:TPoly = read x$9_@2.t
   return