Implement proposed new identity spec.

runtime/vm/intermediate_language.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/intermediate_language.h"
 
 #include "vm/bit_vector.h"
 #include "vm/dart_entry.h"
 #include "vm/flow_graph_allocator.h"
 #include "vm/flow_graph_builder.h"
 #include "vm/flow_graph_compiler.h"
 #include "vm/flow_graph_optimizer.h"
 #include "vm/locations.h"
 #include "vm/object.h"
 #include "vm/object_store.h"
 #include "vm/os.h"
 #include "vm/scopes.h"
 #include "vm/stub_code.h"
 #include "vm/symbols.h"
 
 namespace dart {
 
+DEFINE_FLAG(bool, new_identity_spec, true,
+    "Use new identity check rules for numbers.");
 DEFINE_FLAG(bool, propagate_ic_data, true,
     "Propagate IC data from unoptimized to optimized IC calls.");
 DECLARE_FLAG(bool, enable_type_checks);
 DECLARE_FLAG(int, max_polymorphic_checks);
 
 Definition::Definition()
     : range_(NULL),
       temp_index_(-1),
       ssa_temp_index_(-1),
       propagated_type_(AbstractType::Handle()),
@@ skipping 1744 matching lines @@
   return summary;
 }
 
 
 void StoreContextInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   // Nothing to do.  Context register were loaded by register allocator.
   ASSERT(locs()->in(0).reg() == CTX);
 }
 
 
+StrictCompareInstr::StrictCompareInstr(Token::Kind kind,
+                                       Value* left,
+                                       Value* right)
+    : ComparisonInstr(kind, left, right),
+      needs_number_check_(FLAG_new_identity_spec) {
+  ASSERT((kind == Token::kEQ_STRICT) || (kind == Token::kNE_STRICT));
+}
+
+
 LocationSummary* StrictCompareInstr::MakeLocationSummary() const {
   const intptr_t kNumInputs = 2;
-  const intptr_t kNumTemps = 0;
+  const intptr_t kNumTemps = 00;

[Florian Schneider, 2012/11/23 10:33:40]

s/00/0/

[srdjan, 2012/11/23 19:45:39]

Done.

   LocationSummary* locs =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   locs->set_in(0, Location::RegisterOrConstant(left()));
   locs->set_in(1, Location::RegisterOrConstant(right()));
   locs->set_out(Location::RequiresRegister());
   return locs;
 }
 
 
+// Special code for doubles (compare values instead of references.)

[Florian Schneider, 2012/11/23 10:33:40]

s/doubles/numbers/

[srdjan, 2012/11/23 19:45:39]

Done.

 void StrictCompareInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   ASSERT(kind() == Token::kEQ_STRICT || kind() == Token::kNE_STRICT);
   Location left = locs()->in(0);
   Location right = locs()->in(1);
   if (left.IsConstant() && right.IsConstant()) {
     // TODO(vegorov): should be eliminated earlier by constant propagation.
     const bool result = (kind() == Token::kEQ_STRICT) ?
         left.constant().raw() == right.constant().raw() :
         left.constant().raw() != right.constant().raw();
     __ LoadObject(locs()->out().reg(), result ? compiler->bool_true() :
                                                 compiler->bool_false());
     return;
   }
   if (left.IsConstant()) {
-    compiler->EmitEqualityRegConstCompare(right.reg(), left.constant());
+    compiler->EmitEqualityRegConstCompare(right.reg(),
+                                          left.constant(),
+                                          needs_number_check());
   } else if (right.IsConstant()) {
-    compiler->EmitEqualityRegConstCompare(left.reg(), right.constant());
+    compiler->EmitEqualityRegConstCompare(left.reg(),
+                                          right.constant(),
+                                          needs_number_check());
   } else {
-    __ CompareRegisters(left.reg(), right.reg());
+    compiler->EmitEqualityRegRegCompare(left.reg(),
+                                       right.reg(),
+                                       needs_number_check());
   }
 
   Register result = locs()->out().reg();
   Label load_true, done;
   Condition true_condition = (kind() == Token::kEQ_STRICT) ? EQUAL : NOT_EQUAL;
   __ j(true_condition, &load_true, Assembler::kNearJump);
   __ LoadObject(result, compiler->bool_false());
   __ jmp(&done, Assembler::kNearJump);
   __ Bind(&load_true);
   __ LoadObject(result, compiler->bool_true());
   __ Bind(&done);
 }
 
 
 void StrictCompareInstr::EmitBranchCode(FlowGraphCompiler* compiler,
                                         BranchInstr* branch) {
   ASSERT(kind() == Token::kEQ_STRICT || kind() == Token::kNE_STRICT);
   Location left = locs()->in(0);
   Location right = locs()->in(1);
   if (left.IsConstant() && right.IsConstant()) {
     // TODO(vegorov): should be eliminated earlier by constant propagation.
     const bool result = (kind() == Token::kEQ_STRICT) ?
         left.constant().raw() == right.constant().raw() :
         left.constant().raw() != right.constant().raw();
     branch->EmitBranchOnValue(compiler, result);
     return;
   }
   if (left.IsConstant()) {
-    compiler->EmitEqualityRegConstCompare(right.reg(), left.constant());
+    compiler->EmitEqualityRegConstCompare(right.reg(),
+                                          left.constant(),
+                                          needs_number_check());
   } else if (right.IsConstant()) {
-    compiler->EmitEqualityRegConstCompare(left.reg(), right.constant());
+    compiler->EmitEqualityRegConstCompare(left.reg(),
+                                          right.constant(),
+                                          needs_number_check());
   } else {
-    __ CompareRegisters(left.reg(), right.reg());
+    compiler->EmitEqualityRegRegCompare(left.reg(),
+                                        right.reg(),
+                                        needs_number_check());
   }
 
   Condition true_condition = (kind() == Token::kEQ_STRICT) ? EQUAL : NOT_EQUAL;
   branch->EmitBranchOnCondition(compiler, true_condition);
 }
 
 
 void ClosureCallInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   // The arguments to the stub include the closure, as does the arguments
   // descriptor.
@@ skipping 803 matching lines @@
       return Array::length_offset();
     default:
       UNREACHABLE();
       return -1;
   }
 }
 
 #undef __
 
 }  // namespace dart