From 72c0961071a29ab41e011b59bc50046c04b4d21e Mon Sep 17 00:00:00 2001
From: Arpad Borsos <arpad.borsos@googlemail.com>
Date: Sat, 14 Sep 2019 01:53:04 +0200
Subject: [PATCH 1/2] Force a gc before printing diagnostics

Use this together with `node --expose-gc` to get more stable results
---
 src/tsc/tsc.ts | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/tsc/tsc.ts b/src/tsc/tsc.ts
index fc75e28d504..2e837a09594 100644
--- a/src/tsc/tsc.ts
+++ b/src/tsc/tsc.ts
@@ -322,6 +322,10 @@ namespace ts {
         const compilerOptions = program.getCompilerOptions();
         if (compilerOptions.diagnostics || compilerOptions.extendedDiagnostics) {
             statistics = [];
+
+            // @ts-ignore
+            if (typeof gc === "function") { gc(); }
+
             const memoryUsed = sys.getMemoryUsage ? sys.getMemoryUsage() : -1;
             reportCountStatistic("Files", program.getSourceFiles().length);
             reportCountStatistic("Lines", countLines(program));

From 391a3c8791a8c56e283d39dd0f291156ed304d52 Mon Sep 17 00:00:00 2001
From: Arpad Borsos <arpad.borsos@googlemail.com>
Date: Sat, 14 Sep 2019 04:06:09 +0200
Subject: [PATCH 2/2] Separate Tokens and Identifiers from other Nodes

With some further optimization to their properties, this shrinks the
objects by quite a bit.
---
 src/compiler/utilities.ts | 29 +++++++++++++++++++++++++++--
 1 file changed, 27 insertions(+), 2 deletions(-)

diff --git a/src/compiler/utilities.ts b/src/compiler/utilities.ts
index b338d3ba657..3032b1c3efc 100644
--- a/src/compiler/utilities.ts
+++ b/src/compiler/utilities.ts
@@ -3962,6 +3962,9 @@ namespace ts {
     }
 
     export function getModifierFlags(node: Node): ModifierFlags {
+        if (node.kind >= SyntaxKind.FirstToken && node.kind <= SyntaxKind.LastToken) {
+            return ModifierFlags.None;
+        }
         if (node.modifierFlagsCache & ModifierFlags.HasComputedFlags) {
             return node.modifierFlagsCache & ~ModifierFlags.HasComputedFlags;
         }
@@ -7149,6 +7152,28 @@ namespace ts {
         this.original = undefined;
     }
 
+    function Token(this: Node, kind: SyntaxKind, pos: number, end: number) {
+        this.pos = pos;
+        this.end = end;
+        this.kind = kind;
+        this.id = 0;
+        this.flags = NodeFlags.None;
+        this.transformFlags = TransformFlags.None;
+        this.parent = undefined!;
+    }
+
+    function Identifier(this: Node, kind: SyntaxKind, pos: number, end: number) {
+        this.pos = pos;
+        this.end = end;
+        this.kind = kind;
+        this.id = 0;
+        this.flags = NodeFlags.None;
+        this.transformFlags = TransformFlags.None;
+        this.parent = undefined!;
+        this.original = undefined;
+        this.flowNode = undefined;
+    }
+
     function SourceMapSource(this: SourceMapSource, fileName: string, text: string, skipTrivia?: (pos: number) => number) {
         this.fileName = fileName;
         this.text = text;
@@ -7158,8 +7183,8 @@ namespace ts {
     // eslint-disable-next-line prefer-const
     export let objectAllocator: ObjectAllocator = {
         getNodeConstructor: () => <any>Node,
-        getTokenConstructor: () => <any>Node,
-        getIdentifierConstructor: () => <any>Node,
+        getTokenConstructor: () => <any>Token,
+        getIdentifierConstructor: () => <any>Identifier,
         getSourceFileConstructor: () => <any>Node,
         getSymbolConstructor: () => <any>Symbol,
         getTypeConstructor: () => <any>Type,