[turbofan] Implement rounding of floats on x64 and ia32 without sse4.1.

src/ia32/macro-assembler-ia32.cc

 // Copyright 2012 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.
 
 #if V8_TARGET_ARCH_IA32
 
 #include "src/base/bits.h"
 #include "src/base/division-by-constant.h"
 #include "src/bootstrapper.h"
 #include "src/codegen.h"
@@ skipping 563 matching lines @@
 
 void MacroAssembler::DebugBreak() {
   Move(eax, Immediate(0));
   mov(ebx, Immediate(ExternalReference(Runtime::kHandleDebuggerStatement,
                                        isolate())));
   CEntryStub ces(isolate(), 1);
   call(ces.GetCode(), RelocInfo::DEBUGGER_STATEMENT);
 }
 
 
+void MacroAssembler::Cvtsi2ss(XMMRegister dst, const Operand& src) {
+  xorps(dst, dst);
+  cvtsi2ss(dst, src);
+}
+
+
 void MacroAssembler::Cvtsi2sd(XMMRegister dst, const Operand& src) {
   xorps(dst, dst);
   cvtsi2sd(dst, src);
 }
 
 
 bool MacroAssembler::IsUnsafeImmediate(const Immediate& x) {
   static const int kMaxImmediateBits = 17;
   if (!RelocInfo::IsNone(x.rmode_)) return false;
   return !is_intn(x.x_, kMaxImmediateBits);
@@ skipping 2501 matching lines @@
   mov(eax, dividend);
   shr(eax, 31);
   add(edx, eax);
 }
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_IA32