Inline Math.sqrt in new compilers.

runtime/vm/flow_graph_compiler_x64.cc

Index: runtime/vm/flow_graph_compiler_x64.cc
===================================================================
--- runtime/vm/flow_graph_compiler_x64.cc	(revision 8700)
+++ runtime/vm/flow_graph_compiler_x64.cc	(working copy)
@@ -865,6 +865,30 @@
 }
 
 
+void FlowGraphCompiler::GenerateInlinedMathSqrt(Label* done) {
+  Label smi_to_double, double_op, call_method;
+  __ movq(RAX, Address(RSP, 0));
+  __ testq(RAX, Immediate(kSmiTagMask));
+  __ j(ZERO, &smi_to_double);
+  __ CompareClassId(RAX, kDouble);
+  __ j(NOT_EQUAL, &call_method);
+  __ movsd(XMM1, FieldAddress(RAX, Double::value_offset()));
+  __ Bind(&double_op);
+  __ sqrtsd(XMM0, XMM1);
+  AssemblerMacros::TryAllocate(assembler_,
+                               double_class_,
+                               &call_method,
+                               RAX);  // Result register.
+  __ movsd(FieldAddress(RAX, Double::value_offset()), XMM0);
+  __ jmp(done);
+  __ Bind(&smi_to_double);
+  __ SmiUntag(RAX);
+  __ cvtsi2sd(XMM1, RAX);
+  __ jmp(&double_op);
+  __ Bind(&call_method);
+}
+
+
 void FlowGraphCompiler::CompileGraph() {
   InitCompiler();
   if (TryIntrinsify()) {