Bug 1607494 - Disable Ion for the PAC script thread. r=tcampbell

Differential Revision: https://phabricator.services.mozilla.com/D59467

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

js/public/ContextOptions.h

@@ -31,6 +31,7 @@ class JS_PUBLIC_API ContextOptions {
         enableWasmBigInt_(false),
 #endif
         throwOnAsmJSValidationFailure_(false),
+        disableIon_(false),
         asyncStack_(true),
         throwOnDebuggeeWouldRun_(true),
         dumpStackOnDebuggeeWouldRun_(false),
@@ -118,6 +119,15 @@ class JS_PUBLIC_API ContextOptions {
     return *this;
   }
 
+  // Override to allow disabling Ion for this context irrespective of the
+  // process-wide Ion-enabled setting. This must be set right after creating
+  // the context.
+  bool disableIon() const { return disableIon_; }
+  ContextOptions& setDisableIon() {
+    disableIon_ = true;
+    return *this;
+  }
+
   bool asyncStack() const { return asyncStack_; }
   ContextOptions& setAsyncStack(bool flag) {
     asyncStack_ = flag;
@@ -194,6 +204,7 @@ class JS_PUBLIC_API ContextOptions {
   bool enableWasmBigInt_ : 1;
 #endif
   bool throwOnAsmJSValidationFailure_ : 1;
+  bool disableIon_ : 1;
   bool asyncStack_ : 1;
   bool throwOnDebuggeeWouldRun_ : 1;
   bool dumpStackOnDebuggeeWouldRun_ : 1;

js/src/builtin/TestingFunctions.cpp

@@ -3024,7 +3024,7 @@ static bool testingFunc_inJit(JSContext* cx, unsigned argc, Value* vp) {
 static bool testingFunc_inIon(JSContext* cx, unsigned argc, Value* vp) {
   CallArgs args = CallArgsFromVp(argc, vp);
 
-  if (!jit::IsIonEnabled()) {
+  if (!jit::IsIonEnabled(cx)) {
     return ReturnStringCopy(cx, args, "Ion is disabled.");
   }
 

js/src/jit-test/tests/ion/context-override.js

@@ -0,0 +1,2 @@
+// |jit-test| --no-ion-for-main-context
+assertEq(inIon(), "Ion is disabled.");

js/src/jit/BaselineCodeGen.cpp

@@ -66,7 +66,7 @@ BaselineCompilerHandler::BaselineCompilerHandler(JSContext* cx,
       pc_(script->code()),
       icEntryIndex_(0),
       compileDebugInstrumentation_(script->isDebuggee()),
-      ionCompileable_(jit::IsIonEnabled() && CanIonCompileScript(cx, script)) {
+      ionCompileable_(IsIonEnabled(cx) && CanIonCompileScript(cx, script)) {
 }
 
 BaselineInterpreterHandler::BaselineInterpreterHandler(JSContext* cx,

js/src/jit/CacheIR.cpp

@@ -1828,7 +1828,7 @@ AttachDecision GetPropIRGenerator::tryAttachModuleNamespace(HandleObject obj,
     return AttachDecision::NoAction;
   }
 
-  if (IsIonEnabled()) {
+  if (IsIonEnabled(cx_)) {
     EnsureTrackPropertyTypes(cx_, env, shape->propid());
   }
 
@@ -1894,7 +1894,7 @@ AttachDecision GetPropIRGenerator::tryAttachPrimitive(ValOperandId valId,
     case CanAttachReadSlot: {
       if (holder) {
         // Instantiate this property, for use during Ion compilation.
-        if (IsIonEnabled()) {
+        if (IsIonEnabled(cx_)) {
           EnsureTrackPropertyTypes(cx_, holder, id);
         }
       }
@@ -2492,7 +2492,7 @@ AttachDecision GetNameIRGenerator::tryAttachGlobalNameValue(ObjOperandId objId,
   }
 
   // Instantiate this global property, for use during Ion compilation.
-  if (IsIonEnabled()) {
+  if (IsIonEnabled(cx_)) {
     EnsureTrackPropertyTypes(cx_, holder, id);
   }
 
@@ -2560,7 +2560,7 @@ AttachDecision GetNameIRGenerator::tryAttachGlobalNameGetter(ObjOperandId objId,
     return AttachDecision::NoAction;
   }
 
-  if (IsIonEnabled()) {
+  if (IsIonEnabled(cx_)) {
     EnsureTrackPropertyTypes(cx_, holder, id);
   }
 
@@ -5200,7 +5200,7 @@ AttachDecision CallIRGenerator::tryAttachCallScripted(
 
   // Keep track of the function's |prototype| property in type
   // information, for use during Ion compilation.
-  if (IsIonEnabled()) {
+  if (IsIonEnabled(cx_)) {
     EnsureTrackPropertyTypes(cx_, calleeFunc, NameToId(cx_->names().prototype));
   }
 

js/src/jit/Ion.cpp

@@ -2069,7 +2069,7 @@ static OptimizationLevel GetOptimizationLevel(HandleScript script,
 static MethodStatus Compile(JSContext* cx, HandleScript script,
                             BaselineFrame* osrFrame, uint32_t osrFrameSize,
                             jsbytecode* osrPc, bool forceRecompile = false) {
-  MOZ_ASSERT(jit::IsIonEnabled());
+  MOZ_ASSERT(jit::IsIonEnabled(cx));
   MOZ_ASSERT(jit::IsBaselineJitEnabled());
 
   AutoGeckoProfilerEntry pseudoFrame(
@@ -2169,7 +2169,7 @@ bool jit::OffThreadCompilationAvailable(JSContext* cx) {
 }
 
 MethodStatus jit::CanEnterIon(JSContext* cx, RunState& state) {
-  MOZ_ASSERT(jit::IsIonEnabled());
+  MOZ_ASSERT(jit::IsIonEnabled(cx));
 
   HandleScript script = state.script();
 
@@ -2245,7 +2245,7 @@ MethodStatus jit::CanEnterIon(JSContext* cx, RunState& state) {
 static MethodStatus BaselineCanEnterAtEntry(JSContext* cx, HandleScript script,
                                             BaselineFrame* frame,
                                             uint32_t frameSize) {
-  MOZ_ASSERT(jit::IsIonEnabled());
+  MOZ_ASSERT(jit::IsIonEnabled(cx));
   MOZ_ASSERT(script->canIonCompile());
   MOZ_ASSERT(!script->isIonCompilingOffThread());
   MOZ_ASSERT(!script->hasIonScript());
@@ -2275,7 +2275,7 @@ static MethodStatus BaselineCanEnterAtBranch(JSContext* cx, HandleScript script,
                                              BaselineFrame* osrFrame,
                                              uint32_t osrFrameSize,
                                              jsbytecode* pc) {
-  MOZ_ASSERT(jit::IsIonEnabled());
+  MOZ_ASSERT(jit::IsIonEnabled(cx));
   MOZ_ASSERT((JSOp)*pc == JSOP_LOOPHEAD);
 
   // Skip if the script has been disabled.
@@ -2348,7 +2348,7 @@ static MethodStatus BaselineCanEnterAtBranch(JSContext* cx, HandleScript script,
 
 static bool IonCompileScriptForBaseline(JSContext* cx, BaselineFrame* frame,
                                         uint32_t frameSize, jsbytecode* pc) {
-  MOZ_ASSERT(IsIonEnabled());
+  MOZ_ASSERT(IsIonEnabled(cx));
   MOZ_ASSERT(frame->debugFrameSize() == frameSize);
 
   RootedScript script(cx, frame->script());

js/src/jit/Ion.h

@@ -274,6 +274,11 @@ size_t SizeOfIonData(JSScript* script, mozilla::MallocSizeOf mallocSizeOf);
 bool JitSupportsSimd();
 bool JitSupportsAtomics();
 
+inline bool IsIonEnabled(JSContext* cx) {
+  return IsBaselineJitEnabled() && JitOptions.ion &&
+         !cx->options().disableIon();
+}
+
 }  // namespace jit
 }  // namespace js
 

js/src/jit/IonAnalysis.cpp

@@ -4537,7 +4537,7 @@ bool jit::AnalyzeNewScriptDefiniteProperties(
     return false;
   }
 
-  if (!jit::IsIonEnabled() || !jit::IsBaselineJitEnabled() ||
+  if (!jit::IsIonEnabled(cx) || !jit::IsBaselineJitEnabled() ||
       !CanBaselineInterpretScript(script)) {
     return true;
   }
@@ -4797,7 +4797,7 @@ bool jit::AnalyzeArgumentsUsage(JSContext* cx, JSScript* scriptArg) {
     return true;
   }
 
-  if (!jit::IsIonEnabled()) {
+  if (!jit::IsIonEnabled(cx)) {
     return true;
   }
 

js/src/jit/Jit.cpp

@@ -157,7 +157,7 @@ EnterJitStatus js::jit::MaybeEnterJit(JSContext* cx, RunState& state) {
     script->incWarmUpCounter();
 
     // Try to Ion-compile.
-    if (jit::IsIonEnabled()) {
+    if (jit::IsIonEnabled(cx)) {
       jit::MethodStatus status = jit::CanEnterIon(cx, state);
       if (status == jit::Method_Error) {
         return EnterJitStatus::Error;

js/src/jit/JitOptions.h

@@ -143,8 +143,6 @@ inline bool IsBaselineJitEnabled() {
   return IsBaselineInterpreterEnabled() && JitOptions.baselineJit;
 }
 
-inline bool IsIonEnabled() { return IsBaselineJitEnabled() && JitOptions.ion; }
-
 }  // namespace jit
 }  // namespace js
 

js/src/jit/VMFunctions.cpp

@@ -1211,7 +1211,7 @@ bool RecompileImpl(JSContext* cx, bool force) {
   RootedScript script(cx, frame.script());
   MOZ_ASSERT(script->hasIonScript());
 
-  if (!IsIonEnabled()) {
+  if (!IsIonEnabled(cx)) {
     return true;
   }
 

js/src/jsapi-tests/testPreserveJitCode.cpp

@@ -43,7 +43,7 @@ bool testPreserveJitCode(bool preserveJitCode, unsigned remainingIonScripts) {
 
   // The Ion JIT may be unavailable due to --disable-ion or lack of support
   // for this platform.
-  if (!js::jit::IsIonEnabled()) {
+  if (!js::jit::IsIonEnabled(cx)) {
     knownFail = true;
   }
 

js/src/shell/js.cpp

@@ -10408,6 +10408,10 @@ static bool SetContextOptions(JSContext* cx, const OptionParser& op) {
 #endif
       .setAsyncStack(enableAsyncStacks);
 
+  if (op.getBoolOption("no-ion-for-main-context")) {
+    JS::ContextOptionsRef(cx).setDisableIon();
+  }
+
   if (const char* str = op.getStringOption("cache-ir-stubs")) {
     if (strcmp(str, "on") == 0) {
       jit::JitOptions.disableCacheIR = false;
@@ -11133,6 +11137,8 @@ int main(int argc, char** argv, char** envp) {
                        -1) ||
       !op.addBoolOption('\0', "ion", "Enable IonMonkey (default)") ||
       !op.addBoolOption('\0', "no-ion", "Disable IonMonkey") ||
+      !op.addBoolOption('\0', "no-ion-for-main-context",
+                        "Disable IonMonkey for the main context only") ||
       !op.addBoolOption('\0', "no-asmjs", "Disable asm.js compilation") ||
       !op.addStringOption(
           '\0', "wasm-compiler", "[option]",

netwerk/base/ProxyAutoConfig.cpp

@@ -16,6 +16,7 @@
 #include "nsJSUtils.h"
 #include "jsfriendapi.h"
 #include "js/CompilationAndEvaluation.h"  // JS::Compile{,DontInflate}
+#include "js/ContextOptions.h"
 #include "js/PropertySpec.h"
 #include "js/SourceText.h"  // JS::Source{Ownership,Text}
 #include "js/Utility.h"
@@ -579,6 +580,8 @@ class JSContextWrapper {
     JSContext* cx = JS_NewContext(JS::DefaultHeapMaxBytes + aExtraHeapSize);
     if (NS_WARN_IF(!cx)) return nullptr;
 
+    JS::ContextOptionsRef(cx).setDisableIon();
+
     JSContextWrapper* entry = new JSContextWrapper(cx);
     if (NS_FAILED(entry->Init())) {
       delete entry;