[turbofan] Remove --turbo-asm-deoptimization flag.

R=bmeurer@chromium.org,titzer@chromium.org

Review-Url: https://codereview.chromium.org/2557693006
Cr-Commit-Position: refs/heads/master@{#41579}

src/compiler/pipeline.cc

@@ -575,7 +575,7 @@ PipelineCompilationJob::Status PipelineCompilationJob::PrepareJobImpl() {
     }
   }
   if (info()->is_optimizing_from_bytecode() ||
-      !info()->shared_info()->asm_function() || FLAG_turbo_asm_deoptimization) {
+      !info()->shared_info()->asm_function()) {
     info()->MarkAsDeoptimizationEnabled();
     if (FLAG_inline_accessors) {
       info()->MarkAsAccessorInliningEnabled();

src/debug/debug-frames.cc

@@ -24,8 +24,7 @@ FrameInspector::FrameInspector(StandardFrame* frame, int inlined_jsframe_index,
     DCHECK(js_frame != nullptr);
     // TODO(turbofan): Revisit once we support deoptimization.
     if (js_frame->LookupCode()->is_turbofanned() &&
-        js_frame->function()->shared()->asm_function() &&
-        !FLAG_turbo_asm_deoptimization) {
+        js_frame->function()->shared()->asm_function()) {
       is_optimized_ = false;
       return;
     }
@@ -69,8 +68,7 @@ Handle<Object> FrameInspector::GetExpression(int index) {
   // TODO(turbofan): Revisit once we support deoptimization.
   if (frame_->is_java_script() &&
       javascript_frame()->LookupCode()->is_turbofanned() &&
-      javascript_frame()->function()->shared()->asm_function() &&
-      !FLAG_turbo_asm_deoptimization) {
+      javascript_frame()->function()->shared()->asm_function()) {
     return isolate_->factory()->undefined_value();
   }
   return is_optimized_ ? deoptimized_frame_->GetExpression(index)

src/deoptimizer.cc

@@ -257,9 +257,8 @@ void Deoptimizer::DeoptimizeMarkedCodeForContext(Context* context) {
       SafepointEntry safepoint = code->GetSafepointEntry(it.frame()->pc());
       int deopt_index = safepoint.deoptimization_index();
       // Turbofan deopt is checked when we are patching addresses on stack.
-      bool turbofanned = code->is_turbofanned() &&
-                         function->shared()->asm_function() &&
-                         !FLAG_turbo_asm_deoptimization;
+      bool turbofanned =
+          code->is_turbofanned() && function->shared()->asm_function();
       bool safe_to_deopt =
           deopt_index != Safepoint::kNoDeoptimizationIndex || turbofanned;
       bool builtin = code->kind() == Code::BUILTIN;

src/flag-definitions.h

@@ -419,7 +419,6 @@ DEFINE_BOOL(omit_map_checks_for_leaf_maps, true,
 
 // Flags for TurboFan.
 DEFINE_BOOL(turbo, false, "enable TurboFan compiler")
-DEFINE_IMPLICATION(turbo, turbo_asm_deoptimization)
 DEFINE_BOOL(turbo_sp_frame_access, false,
             "use stack pointer-relative access to frame wherever possible")
 DEFINE_BOOL(turbo_preprocess_ranges, true,
@@ -439,8 +438,6 @@ DEFINE_BOOL(trace_turbo_jt, false, "trace TurboFan's jump threading")
 DEFINE_BOOL(trace_turbo_ceq, false, "trace TurboFan's control equivalence")
 DEFINE_BOOL(trace_turbo_loop, false, "trace TurboFan's loop optimizations")
 DEFINE_BOOL(turbo_asm, true, "enable TurboFan for asm.js code")
-DEFINE_BOOL(turbo_asm_deoptimization, false,
-            "enable deoptimization in TurboFan for asm.js code")
 DEFINE_BOOL(turbo_verify, DEBUG_BOOL, "verify TurboFan graphs at each phase")
 DEFINE_STRING(turbo_verify_machine_graph, nullptr,
               "verify TurboFan machine graph before instruction selection")

src/frames.cc

@@ -1112,8 +1112,7 @@ int JavaScriptFrame::ComputeParametersCount() const {
 namespace {
 
 bool CannotDeoptFromAsmCode(Code* code, JSFunction* function) {
-  return code->is_turbofanned() && function->shared()->asm_function() &&
-         !FLAG_turbo_asm_deoptimization;
+  return code->is_turbofanned() && function->shared()->asm_function();
 }
 
 }  // namespace

src/isolate.cc

@@ -1342,7 +1342,6 @@ HandlerTable::CatchPrediction PredictException(JavaScriptFrame* frame) {
         }
         if (code->kind() == AbstractCode::OPTIMIZED_FUNCTION) {
           DCHECK(summary.function()->shared()->asm_function());
-          DCHECK(!FLAG_turbo_asm_deoptimization);
           // asm code cannot contain try-catch.
           continue;
         }

src/runtime/runtime-test.cc

@@ -48,7 +48,7 @@ RUNTIME_FUNCTION(Runtime_DeoptimizeFunction) {
 
   // TODO(turbofan): Deoptimization is not supported yet.
   if (function->code()->is_turbofanned() &&
-      function->shared()->asm_function() && !FLAG_turbo_asm_deoptimization) {
+      function->shared()->asm_function()) {
     return isolate->heap()->undefined_value();
   }
 
@@ -74,7 +74,7 @@ RUNTIME_FUNCTION(Runtime_DeoptimizeNow) {
 
   // TODO(turbofan): Deoptimization is not supported yet.
   if (function->code()->is_turbofanned() &&
-      function->shared()->asm_function() && !FLAG_turbo_asm_deoptimization) {
+      function->shared()->asm_function()) {
     return isolate->heap()->undefined_value();
   }
 

test/mjsunit/compiler/regress-uint8-deopt.js

-// Copyright 2014 the V8 project authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-// Flags: --turbo-asm --turbo-asm-deoptimization --allow-natives-syntax
-
-function Module(heap) {
-  "use asm";
-  var a = new Uint8Array(heap);
-  function f() {
-    var x = a[0] | 0;
-    %DeoptimizeFunction(f);
-    return x;
-  }
-  return f;
-}
-assertEquals(0, Module(new ArrayBuffer(1))());