ICData::NumberOfChecks is O(n) so don't call it in loops

runtime/vm/flow_graph_compiler_x64.cc

Index: runtime/vm/flow_graph_compiler_x64.cc
diff --git a/runtime/vm/flow_graph_compiler_x64.cc b/runtime/vm/flow_graph_compiler_x64.cc
index 6c69c8062be31eaeab8bcd0b3e87eced12d3850d..1a29be51c2e3409778447c736722c4801831f80d 100644
--- a/runtime/vm/flow_graph_compiler_x64.cc
+++ b/runtime/vm/flow_graph_compiler_x64.cc
@@ -1465,15 +1465,15 @@ void FlowGraphCompiler::EmitTestAndCall(const ICData& ic_data,
   __ LoadObject(R10, arguments_descriptor);
 
   const bool kFirstCheckIsSmi = ic_data.GetReceiverClassIdAt(0) == kSmiCid;
-  const intptr_t kNumChecks = ic_data.NumberOfChecks();
+  const intptr_t num_checks = ic_data.NumberOfChecks();
 
-  ASSERT(!ic_data.IsNull() && (kNumChecks > 0));
+  ASSERT(!ic_data.IsNull() && (num_checks > 0));
 
   Label after_smi_test;
   if (kFirstCheckIsSmi) {
     __ testq(RAX, Immediate(kSmiTagMask));
     // Jump if receiver is not Smi.
-    if (kNumChecks == 1) {
+    if (num_checks == 1) {
       __ j(NOT_ZERO, failed);
     } else {
       __ j(NOT_ZERO, &after_smi_test);
@@ -1486,7 +1486,7 @@ void FlowGraphCompiler::EmitTestAndCall(const ICData& ic_data,
                            *StubCode::CallStaticFunction_entry(),
                            RawPcDescriptors::kOther, locs, function);
     __ Drop(argument_count, RCX);
-    if (kNumChecks > 1) {
+    if (num_checks > 1) {
       __ jmp(match_found);
     }
   } else {
@@ -1499,8 +1499,8 @@ void FlowGraphCompiler::EmitTestAndCall(const ICData& ic_data,
   }
   __ Bind(&after_smi_test);
 
-  ASSERT(!ic_data.IsNull() && (kNumChecks > 0));
-  GrowableArray<CidTarget> sorted(kNumChecks);
+  ASSERT(!ic_data.IsNull() && (num_checks > 0));
+  GrowableArray<CidTarget> sorted(num_checks);
   SortICDataByCount(ic_data, &sorted, /* drop_smi = */ true);
 
   const intptr_t kSortedLen = sorted.length();