Emit comment with instruction+reason before deopt calls.

src/arm/lithium-codegen-arm.cc

Index: src/arm/lithium-codegen-arm.cc
diff --git a/src/arm/lithium-codegen-arm.cc b/src/arm/lithium-codegen-arm.cc
index 87fcd60e78e5e8081b24713ba2b9fa52f8a26b1c..b20f8b080bc108b0283b62c8a3cc273cae989f56 100644
--- a/src/arm/lithium-codegen-arm.cc
+++ b/src/arm/lithium-codegen-arm.cc
@@ -336,21 +336,23 @@ bool LCodeGen::GenerateDeoptJumpTable() {
 
     int length = deopt_jump_table_.length();
     for (int i = 0; i < length; i++) {
-      __ bind(&deopt_jump_table_[i].label);
+      Deoptimizer::JumpTableEntry* table_entry = &deopt_jump_table_[i];
+      __ bind(&table_entry->label);
 
-      Deoptimizer::BailoutType type = deopt_jump_table_[i].bailout_type;
+      Deoptimizer::BailoutType type = table_entry->bailout_type;
       DCHECK(type == deopt_jump_table_[0].bailout_type);
-      Address entry = deopt_jump_table_[i].address;
+      Address entry = table_entry->address;
       int id = Deoptimizer::GetDeoptimizationId(isolate(), entry, type);
       DCHECK(id != Deoptimizer::kNotDeoptimizationEntry);
       Comment(";;; jump table entry %d: deoptimization bailout %d.", i, id);
+      DeoptComment(table_entry->mnemonic, table_entry->reason);
 
       // Second-level deopt table entries are contiguous and small, so instead
       // of loading the full, absolute address of each one, load an immediate
       // offset which will be added to the base address later.
       __ mov(entry_offset, Operand(entry - base));
 
-      if (deopt_jump_table_[i].needs_frame) {
+      if (table_entry->needs_frame) {
         DCHECK(!info()->saves_caller_doubles());
         if (needs_frame.is_bound()) {
           __ b(&needs_frame);
@@ -847,6 +849,7 @@ void LCodeGen::RegisterEnvironmentForDeoptimization(LEnvironment* environment,
 
 
 void LCodeGen::DeoptimizeIf(Condition condition, LInstruction* instr,
+                            const char* reason,
                             Deoptimizer::BailoutType bailout_type) {
   LEnvironment* environment = instr->environment();
   RegisterEnvironmentForDeoptimization(environment, Safepoint::kNoLazyDeopt);
@@ -904,6 +907,7 @@ void LCodeGen::DeoptimizeIf(Condition condition, LInstruction* instr,
   // restore caller doubles.
   if (condition == al && frame_is_built_ &&
       !info()->saves_caller_doubles()) {
+    DeoptComment(instr->Mnemonic(), reason);
     __ Call(entry, RelocInfo::RUNTIME_ENTRY);
   } else {
     // We often have several deopts to the same entry, reuse the last
@@ -912,9 +916,8 @@ void LCodeGen::DeoptimizeIf(Condition condition, LInstruction* instr,
         (deopt_jump_table_.last().address != entry) ||
         (deopt_jump_table_.last().bailout_type != bailout_type) ||
         (deopt_jump_table_.last().needs_frame != !frame_is_built_)) {
-      Deoptimizer::JumpTableEntry table_entry(entry,
-                                              bailout_type,
-                                              !frame_is_built_);
+      Deoptimizer::JumpTableEntry table_entry(entry, instr->Mnemonic(), reason,
+                                              bailout_type, !frame_is_built_);
       deopt_jump_table_.Add(table_entry, zone());
     }
     __ b(condition, &deopt_jump_table_.last().label);
@@ -922,11 +925,12 @@ void LCodeGen::DeoptimizeIf(Condition condition, LInstruction* instr,
 }
 
 
-void LCodeGen::DeoptimizeIf(Condition condition, LInstruction* instr) {
+void LCodeGen::DeoptimizeIf(Condition condition, LInstruction* instr,
+                            const char* reason) {
   Deoptimizer::BailoutType bailout_type = info()->IsStub()
       ? Deoptimizer::LAZY
       : Deoptimizer::EAGER;
-  DeoptimizeIf(condition, instr, bailout_type);
+  DeoptimizeIf(condition, instr, reason, bailout_type);
 }
 
 
@@ -5665,8 +5669,7 @@ void LCodeGen::DoDeoptimize(LDeoptimize* instr) {
     type = Deoptimizer::LAZY;
   }
 
-  Comment(";;; deoptimize: %s", instr->hydrogen()->reason());
-  DeoptimizeIf(al, instr, type);
+  DeoptimizeIf(al, instr, instr->hydrogen()->reason(), type);
 }