Bug 1523015 - Summary: Enable Ion on ARM64, but disable in-browser by pref. r=nbp

Differential Revision: https://phabricator.services.mozilla.com/D19448

--HG--
extra : moz-landing-system : lando

js/public/ContextOptions.h

@@ -19,9 +19,15 @@ class JS_PUBLIC_API ContextOptions {
  public:
   ContextOptions()
       : baseline_(true),
+#ifdef JS_CODEGEN_ARM64
+        ion_(false),
+        asmJS_(false),
+        wasm_(false),
+#else
         ion_(true),
         asmJS_(true),
         wasm_(true),
+#endif
         wasmVerbose_(false),
         wasmBaseline_(true),
         wasmIon_(true),

js/src/jit-test/lib/jitopts.js

@@ -9,13 +9,6 @@ function jitTogglesMatch(opts) {
     if (k.indexOf(".enable") > 0 && opts[k] != currentOpts[k])
       return false;
   }
-
-  // ARM64 does not yet have an Ion code generator, so return false if
-  // ion.enable is requested.
-  var conf = getBuildConfiguration();
-  if (conf['arm64'] && opts['ion.enable'])
-    return false;
-
   return true;
 }
 

js/src/jit-test/tests/ion/bug1165905.js

@@ -1,3 +1,4 @@
+// |jit-test| skip-if: !this.getJitCompilerOptions() || !this.getJitCompilerOptions()['ion.enable']
 load(libdir + "asserts.js");
 var oldOpts = getJitCompilerOptions();
 for (var k in oldOpts)

js/src/jit/Ion.h

@@ -160,8 +160,7 @@ void LinkIonScript(JSContext* cx, HandleScript calleescript);
 uint8_t* LazyLinkTopActivation(JSContext* cx, LazyLinkExitFrameLayout* frame);
 
 static inline bool IsIonEnabled(JSContext* cx) {
-  // The ARM64 Ion engine is not yet implemented.
-#if defined(JS_CODEGEN_NONE) || defined(JS_CODEGEN_ARM64)
+#if defined(JS_CODEGEN_NONE)
   return false;
 #else
   return cx->options().ion() && cx->options().baseline() &&

js/src/shell/js.cpp

@@ -9843,14 +9843,25 @@ static MOZ_MUST_USE bool ProcessArgs(JSContext* cx, OptionParser* op) {
 
 static bool SetContextOptions(JSContext* cx, const OptionParser& op) {
   enableBaseline = !op.getBoolOption("no-baseline");
+#ifdef JS_CODEGEN_ARM64
+  // TODO: Enable Ion by default.
+  enableIon = false;
+  enableAsmJS = false;
+#else
   enableIon = !op.getBoolOption("no-ion");
   enableAsmJS = !op.getBoolOption("no-asmjs");
+#endif
   enableNativeRegExp = !op.getBoolOption("no-native-regexp");
 
   // Default values for wasm.
   enableWasm = true;
   enableWasmBaseline = true;
+#ifdef JS_CODEGEN_ARM64
+  // TODO: Enable WasmIon by default.
+  enableWasmIon = false;
+#else
   enableWasmIon = true;
+#endif
   if (const char* str = op.getStringOption("wasm-compiler")) {
     if (strcmp(str, "none") == 0) {
       enableWasm = false;

modules/libpref/init/all.js

@@ -1462,7 +1462,11 @@ pref("javascript.options.unboxed_objects",  false);
 pref("javascript.options.baselinejit",      true);
 //Duplicated in JitOptions - ensure both match.
 pref("javascript.options.baselinejit.threshold", 10);
+#ifdef _ARM64_
+pref("javascript.options.ion",              false);
+#else
 pref("javascript.options.ion",              true);
+#endif
 //Duplicated in JitOptions - ensure both match.
 pref("javascript.options.ion.threshold",    1000);
 //Duplicated in JitOptions - ensure both match.