Split IdenticalWithNumberCheck in two versions: once called from unoptimized code the other called…

runtime/vm/stub_code_ia32.cc

 // Copyright (c) 2013, 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/globals.h"
 #if defined(TARGET_ARCH_IA32)
 
 #include "vm/assembler.h"
 #include "vm/compiler.h"
 #include "vm/dart_entry.h"
@@ skipping 2046 matching lines @@
 
 
 DECLARE_LEAF_RUNTIME_ENTRY(intptr_t,
                            BigintCompare,
                            RawBigint* left,
                            RawBigint* right);
 
 
 // Does identical check (object references are equal or not equal) with special
 // checks for boxed numbers.
-// Left and right are pushed on stack.
 // Return ZF set.
 // Note: A Mint cannot contain a value that would fit in Smi, a Bigint
 // cannot contain a value that fits in Mint or Smi.
-void StubCode::GenerateIdenticalWithNumberCheckStub(Assembler* assembler) {
-  const Register left = EAX;
-  const Register right = EDX;
-  const Register temp = ECX;
-  // Preserve left, right and temp.
-  __ pushl(left);
-  __ pushl(right);
-  __ pushl(temp);
-  // TOS + 0: saved temp
-  // TOS + 1: saved right
-  // TOS + 2: saved left
-  // TOS + 3: return address
-  // TOS + 4: right argument.
-  // TOS + 5: left argument.
-  __ movl(left, Address(ESP, 5 * kWordSize));
-  __ movl(right, Address(ESP, 4 * kWordSize));
+void StubCode::GenerateIdenticalWithNumberCheckStub(Assembler* assembler,
+                                                    const Register left,
+                                                    const Register right,
+                                                    const Register temp,
+                                                    const Register unused) {
   Label reference_compare, done, check_mint, check_bigint;
   // If any of the arguments is Smi do reference compare.
   __ testl(left, Immediate(kSmiTagMask));
   __ j(ZERO, &reference_compare, Assembler::kNearJump);
   __ testl(right, Immediate(kSmiTagMask));
   __ j(ZERO, &reference_compare, Assembler::kNearJump);
 
   // Value compare for two doubles.
   __ CompareClassId(left, kDoubleCid, temp);
   __ j(NOT_EQUAL, &check_mint, Assembler::kNearJump);
@@ skipping 31 matching lines @@
   __ movl(Address(ESP, 0 * kWordSize), right);
   __ CallRuntime(kBigintCompareRuntimeEntry);
   // Result in EAX, 0 means equal.
   __ LeaveFrame();
   __ cmpl(EAX, Immediate(0));
   __ jmp(&done);
 
   __ Bind(&reference_compare);
   __ cmpl(left, right);
   __ Bind(&done);
+}
+
+
+// Called only from unoptimized code. All relevant registers have been saved.
+// TOS + 0: return address
+// TOS + 1: right argument.
+// TOS + 2: left argument.
+// Returns ZF set.
+void StubCode::GenerateUnoptimizedIdenticalWithNumberCheckStub(
+    Assembler* assembler) {
+  const Register left = EAX;
+  const Register right = EDX;
+  const Register temp = ECX;
+  __ movl(left, Address(ESP, 2 * kWordSize));
+  __ movl(right, Address(ESP, 1 * kWordSize));
+  GenerateIdenticalWithNumberCheckStub(assembler, left, right, temp);
+  __ ret();
+}
+
+
+// Called from otpimzied code only. Must preserve any registers that are
+// destroyed.
+// TOS + 0: return address
+// TOS + 1: right argument.
+// TOS + 2: left argument.
+// Returns ZF set.
+void StubCode::GenerateOptimizedIdenticalWithNumberCheckStub(
+    Assembler* assembler) {
+  const Register left = EAX;
+  const Register right = EDX;
+  const Register temp = ECX;
+  // Preserve left, right and temp.
+  __ pushl(left);
+  __ pushl(right);
+  __ pushl(temp);
+  __ movl(left, Address(ESP, 5 * kWordSize));
+  __ movl(right, Address(ESP, 4 * kWordSize));
+  GenerateIdenticalWithNumberCheckStub(assembler, left, right, temp);
   __ popl(temp);
   __ popl(right);
   __ popl(left);
   __ ret();
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_IA32