Lattice-based representation inference, powered by left/right specific type feedback for BinaryOps …

src/arm/lithium-codegen-arm.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 212 matching lines @@
   for (current_instruction_ = 0;
        !is_aborted() && current_instruction_ < instructions_->length();
        current_instruction_++) {
     LInstruction* instr = instructions_->at(current_instruction_);
     if (instr->IsLabel()) {
       LLabel* label = LLabel::cast(instr);
       emit_instructions = !label->HasReplacement();
     }
 
     if (emit_instructions) {
-      Comment(";;; @%d: %s.", current_instruction_, instr->Mnemonic());
+      if (FLAG_code_comments) {
+        HValue* hydrogen = instr->hydrogen_value();
+        if (hydrogen != NULL) {
+          if (hydrogen->IsChange()) {
+            HValue* changed_value = HChange::cast(hydrogen)->value();
+            int use_id = 0;
+            const char* use_mnemo = "dead";
+            if (hydrogen->UseCount() >= 1) {
+              HValue* use_value = hydrogen->uses().value();
+              use_id = use_value->id();
+              use_mnemo = use_value->Mnemonic();
+            }
+            Comment(";;; @%d: %s. <of #%d %s for #%d %s>",
+                    current_instruction_, instr->Mnemonic(),
+                    changed_value->id(), changed_value->Mnemonic(),
+                    use_id, use_mnemo);
+          } else {
+            Comment(";;; @%d: %s. <#%d>", current_instruction_,
+                    instr->Mnemonic(), hydrogen->id());
+          }
+        } else {
+          Comment(";;; @%d: %s.", current_instruction_, instr->Mnemonic());
+        }
+      }
       instr->CompileToNative(this);
     }
   }
   EnsureSpaceForLazyDeopt();
   return !is_aborted();
 }
 
 
 bool LCodeGen::GenerateDeferredCode() {
   ASSERT(is_generating());
@@ skipping 5471 matching lines @@
   __ sub(scratch, result, Operand(index, LSL, kPointerSizeLog2 - kSmiTagSize));
   __ ldr(result, FieldMemOperand(scratch,
                                  FixedArray::kHeaderSize - kPointerSize));
   __ bind(&done);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal