Introduce a class to carry around a deoptimization reason.

src/ia32/lithium-codegen-ia32.cc

Index: src/ia32/lithium-codegen-ia32.cc
diff --git a/src/ia32/lithium-codegen-ia32.cc b/src/ia32/lithium-codegen-ia32.cc
index 259fbf0c39a42bb92a6e96a22c407b84ad83e698..eeb2472f85fb8b4ec46fef2c8ae05d2d0eb42056 100644
--- a/src/ia32/lithium-codegen-ia32.cc
+++ b/src/ia32/lithium-codegen-ia32.cc
@@ -390,7 +390,7 @@ bool LCodeGen::GenerateJumpTable() {
     int id = Deoptimizer::GetDeoptimizationId(isolate(), entry, type);
     DCHECK_NE(Deoptimizer::kNotDeoptimizationEntry, id);
     Comment(";;; jump table entry %d: deoptimization bailout %d.", i, id);
-    DeoptComment(table_entry->mnemonic, table_entry->reason);
+    DeoptComment(table_entry->reason);
     if (table_entry->needs_frame) {
       DCHECK(!info()->saves_caller_doubles());
       __ push(Immediate(ExternalReference::ForDeoptEntry(entry)));
@@ -825,7 +825,7 @@ void LCodeGen::RegisterEnvironmentForDeoptimization(
 
 
 void LCodeGen::DeoptimizeIf(Condition cc, LInstruction* instr,
-                            const char* reason,
+                            const char* detail,
                             Deoptimizer::BailoutType bailout_type) {
   LEnvironment* environment = instr->environment();
   RegisterEnvironmentForDeoptimization(environment, Safepoint::kNoLazyDeopt);
@@ -867,9 +867,10 @@ void LCodeGen::DeoptimizeIf(Condition cc, LInstruction* instr,
     __ bind(&done);
   }
 
+  Deoptimizer::Reason reason(instr->Mnemonic(), detail);
   DCHECK(info()->IsStub() || frame_is_built_);
   if (cc == no_condition && frame_is_built_) {
-    DeoptComment(instr->Mnemonic(), reason);
+    DeoptComment(reason);
     __ call(entry, RelocInfo::RUNTIME_ENTRY);
   } else {
     // We often have several deopts to the same entry, reuse the last
@@ -878,8 +879,8 @@ void LCodeGen::DeoptimizeIf(Condition cc, LInstruction* instr,
         jump_table_.last().address != entry ||
         jump_table_.last().needs_frame != !frame_is_built_ ||
         jump_table_.last().bailout_type != bailout_type) {
-      Deoptimizer::JumpTableEntry table_entry(entry, instr->Mnemonic(), reason,
-                                              bailout_type, !frame_is_built_);
+      Deoptimizer::JumpTableEntry table_entry(entry, reason, bailout_type,
+                                              !frame_is_built_);
       jump_table_.Add(table_entry, zone());
     }
     if (cc == no_condition) {
@@ -892,11 +893,11 @@ void LCodeGen::DeoptimizeIf(Condition cc, LInstruction* instr,
 
 
 void LCodeGen::DeoptimizeIf(Condition cc, LInstruction* instr,
-                            const char* reason) {
+                            const char* detail) {
   Deoptimizer::BailoutType bailout_type = info()->IsStub()
       ? Deoptimizer::LAZY
       : Deoptimizer::EAGER;
-  DeoptimizeIf(cc, instr, reason, bailout_type);
+  DeoptimizeIf(cc, instr, detail, bailout_type);
 }