Added slow_assert macro and flag for slow development assertions in the VM.

runtime/vm/flow_graph.cc

Index: runtime/vm/flow_graph.cc
diff --git a/runtime/vm/flow_graph.cc b/runtime/vm/flow_graph.cc
index d434d610ebed6c587bd311253424cd663142f8e5..d0bf4d4a2c9adcaeb56542e89e6389486fe60cff 100644
--- a/runtime/vm/flow_graph.cc
+++ b/runtime/vm/flow_graph.cc
@@ -4,6 +4,7 @@
 
 #include "vm/flow_graph.h"
 
+#include "vm/assert.h"
 #include "vm/bit_vector.h"
 #include "vm/flow_graph_builder.h"
 #include "vm/intermediate_language.h"
@@ -133,14 +134,14 @@ static void ValidateUseListsInInstruction(Instruction* instr) {
   for (intptr_t i = 0; i < instr->InputCount(); ++i) {
     Value* use = instr->InputAt(i);
     ASSERT(use->use_index() == i);
-    ASSERT(1 == MembershipCount(use, use->definition()->input_use_list()));
+    SLOW_ASSERT(1 == MembershipCount(use, use->definition()->input_use_list()));

[siva, 2012/10/01 23:35:40]

It sounds like this needs to be
ASSERT(VerifyMembershipCount(use, use->definition()->input_use_list()));

if MemberShipCount is a very expensive operation and you do not want it executed
all the time then maybe you could have a '--verify-compiler-state' or some
equivalent flag and all these verification could be conditional on this flag.

   }
   if (instr->env() != NULL) {
     intptr_t use_index = 0;
     for (Environment::DeepIterator it(instr->env()); !it.Done(); it.Advance()) {
       Value* use = it.CurrentValue();
       ASSERT(use->use_index() == use_index++);
-      ASSERT(1 == MembershipCount(use, use->definition()->env_use_list()));
+      SLOW_ASSERT(1 == MembershipCount(use, use->definition()->env_use_list()));
     }
   }
   Definition* defn = instr->AsDefinition();
@@ -203,8 +204,7 @@ static void RecordInputUses(Instruction* instr) {
     ASSERT(use->instruction() == NULL);
     ASSERT(use->use_index() == -1);
     ASSERT(use->next_use() == NULL);
-    DEBUG_ASSERT(0 == MembershipCount(use,
-                                      use->definition()->input_use_list()));
+    SLOW_ASSERT(0 == MembershipCount(use, use->definition()->input_use_list()));
     use->set_instruction(instr);
     use->set_use_index(i);
     use->AddToInputUseList();
@@ -221,7 +221,7 @@ static void RecordEnvUses(Instruction* instr) {
     ASSERT(use->instruction() == NULL);
     ASSERT(use->use_index() == -1);
     ASSERT(use->next_use() == NULL);
-    DEBUG_ASSERT(0 == MembershipCount(use, use->definition()->env_use_list()));
+    SLOW_ASSERT(0 == MembershipCount(use, use->definition()->env_use_list()));
     use->set_instruction(instr);
     use->set_use_index(use_index++);
     use->AddToEnvUseList();
@@ -264,8 +264,8 @@ static void ComputeUseListsRecursive(BlockEntryInstr* block) {
         ASSERT(use->instruction() == NULL);
         ASSERT(use->use_index() == -1);
         ASSERT(use->next_use() == NULL);
-        DEBUG_ASSERT(0 == MembershipCount(use,
-                                          use->definition()->input_use_list()));
+        SLOW_ASSERT(0 == MembershipCount(use,
+                                         use->definition()->input_use_list()));
         use->set_instruction(phi);
         use->set_use_index(pred_index);
         use->AddToInputUseList();
@@ -282,7 +282,7 @@ void FlowGraph::ComputeUseLists() {
     ClearUseLists((*graph_entry_->initial_definitions())[i]);
   }
   ComputeUseListsRecursive(graph_entry_);
-  DEBUG_ASSERT(ValidateUseLists());
+  SLOW_ASSERT(ValidateUseLists());

[siva, 2012/10/01 23:35:40]

Ditto comment, this would be
ASSERT(ValidateUseLists());

and if that is an expensive operation you could conditionalize it under
'--verify-compiler-state'

 }