From 7fff53cf33fe3c9c8547256cf3d8e38d389d368b Mon Sep 17 00:00:00 2001
From: Cyrus Najmabadi <cyrusn@microsoft.com>
Date: Sat, 28 Mar 2015 23:50:52 -0700
Subject: [PATCH] Remove experimental flag to cache for-of length checks.

---
 Jakefile                          |  2 +-
 src/compiler/commandLineParser.ts |  6 ------
 src/compiler/emitter.ts           | 19 ++-----------------
 src/compiler/types.ts             |  1 -
 4 files changed, 3 insertions(+), 25 deletions(-)

diff --git a/Jakefile b/Jakefile
index dd09085800cae..8f3bdffaa5d56 100644
--- a/Jakefile
+++ b/Jakefile
@@ -254,7 +254,7 @@ function compileFile(outFile, sources, prereqs, prefixes, useBuiltCompiler, noOu
             options += " --stripInternal"
         }
 
-        options += " --cacheDownlevelForOfLength --preserveNewLines";
+        options += " --preserveNewLines";
 
         var cmd = host + " " + dir + compilerFilename + " " + options + " ";
         cmd = cmd + sources.join(" ");
diff --git a/src/compiler/commandLineParser.ts b/src/compiler/commandLineParser.ts
index 269f23492e20c..e79d762524c12 100644
--- a/src/compiler/commandLineParser.ts
+++ b/src/compiler/commandLineParser.ts
@@ -146,12 +146,6 @@ module ts {
             description: Diagnostics.Preserve_new_lines_when_emitting_code,
             experimental: true
         },
-        {
-            name: "cacheDownlevelForOfLength",
-            type: "boolean",
-            description: "Cache length access when downlevel emitting for-of statements",
-            experimental: true,
-        },
         {
             name: "target",
             shortName: "t",
diff --git a/src/compiler/emitter.ts b/src/compiler/emitter.ts
index 71a3543268563..249651def2fbf 100644
--- a/src/compiler/emitter.ts
+++ b/src/compiler/emitter.ts
@@ -2168,8 +2168,6 @@ module ts {
                 let counter = createTempVariable(TempFlags._i);
                 let rhsReference = rhsIsIdentifier ? <Identifier>node.expression : createTempVariable(TempFlags.Auto);
 
-                var cachedLength = compilerOptions.cacheDownlevelForOfLength ? createTempVariable(TempFlags._n) : undefined;
-
                 // This is the let keyword for the counter and rhsReference. The let keyword for
                 // the LHS will be emitted inside the body.
                 emitStart(node.expression);
@@ -2190,14 +2188,6 @@ module ts {
                     emitEnd(node.expression);
                 }
 
-                if (cachedLength) {
-                    write(", ");
-                    emitNodeWithoutSourceMap(cachedLength);
-                    write(" = ");
-                    emitNodeWithoutSourceMap(rhsReference);
-                    write(".length");
-                }
-
                 write("; ");
                 
                 // _i < _a.length;
@@ -2205,13 +2195,8 @@ module ts {
                 emitNodeWithoutSourceMap(counter);
                 write(" < ");
 
-                if (cachedLength) {
-                    emitNodeWithoutSourceMap(cachedLength);
-                }
-                else {
-                    emitNodeWithoutSourceMap(rhsReference);
-                    write(".length");
-                }
+                emitNodeWithoutSourceMap(rhsReference);
+                write(".length");
 
                 emitEnd(node.initializer);
                 write("; ");
diff --git a/src/compiler/types.ts b/src/compiler/types.ts
index e5697f9f37239..892f51d990630 100644
--- a/src/compiler/types.ts
+++ b/src/compiler/types.ts
@@ -1589,7 +1589,6 @@ module ts {
         watch?: boolean;
         /* @internal */ stripInternal?: boolean;
         /* @internal */ preserveNewLines?: boolean;
-        /* @internal */ cacheDownlevelForOfLength?: boolean;
         [option: string]: string | number | boolean;
     }