Implement Smi binops ia32 (new compiler).

runtime/vm/intermediate_language_x64.cc

Index: runtime/vm/intermediate_language_x64.cc
===================================================================
--- runtime/vm/intermediate_language_x64.cc	(revision 8442)
+++ runtime/vm/intermediate_language_x64.cc	(working copy)
@@ -815,9 +815,7 @@
 }
 
 
-// TODO(srdjan): Implement variations.
 static void EmitSmiBinaryOp(FlowGraphCompiler* compiler, BinaryOpComp* comp) {
-  // TODO(srdjan): need to allocate a temporary register (now using r10)
   Register left = comp->locs()->in(0).reg();
   Register right = comp->locs()->in(1).reg();
   Register result = comp->locs()->out().reg();
@@ -890,7 +888,8 @@
       break;
     }
     case Token::kSHR: {
-      const Immediate kCountLimit = Immediate(0x1F);
+      // The count is masked to 6 bits on x64.

[Vyacheslav Egorov (Google), 2012/06/08 16:43:25]

It's not masking. It's clamping between 0 and number-of-smi-bits.

[srdjan, 2012/06/08 16:50:33]

Clarifying comment: sarq operations masks the count to 6bits.

+      const Immediate kCountLimit = Immediate(0x3F);

[Vyacheslav Egorov (Google), 2012/06/08 16:43:25]

Nice catch!

Can we add a regression test to ensure proper coverage? 

[srdjan, 2012/06/08 16:50:33]

The previous worked as well, we just went to slow case... we would need to add
regression benchmarks .. a whole bunch of them.

       __ cmpq(right, Immediate(0));
       __ j(LESS, deopt);
       __ SmiUntag(right);
@@ -899,7 +898,7 @@
       __ j(LESS, &count_ok, Assembler::kNearJump);
       __ movq(right, kCountLimit);
       __ Bind(&count_ok);
-      ASSERT(right == RCX);  // Count must be in ECX
+      ASSERT(right == RCX);  // Count must be in RCX
       __ SmiUntag(left);
       __ sarq(left, right);
       __ SmiTag(left);
@@ -948,7 +947,7 @@
 }
 
 
-static bool EmitDoubleBinaryOp(FlowGraphCompiler* compiler,
+static void EmitDoubleBinaryOp(FlowGraphCompiler* compiler,
                                BinaryOpComp* comp) {
   Register left = comp->locs()->in(0).reg();
   Register right = comp->locs()->in(1).reg();
@@ -991,7 +990,6 @@
   }
 
   __ movsd(FieldAddress(result, Double::value_offset()), XMM0);
-  return true;
 }