[turbofan] remove some of the dependency of Instruction on Schedule

src/compiler/mips/code-generator-mips.cc

Index: src/compiler/mips/code-generator-mips.cc
diff --git a/src/compiler/mips/code-generator-mips.cc b/src/compiler/mips/code-generator-mips.cc
index 19d1b024e01cc9b2ecaac2dd9902dd25ec6fdc2f..8dcca27601ecf684d2de257ab017e3aa200d7482 100644
--- a/src/compiler/mips/code-generator-mips.cc
+++ b/src/compiler/mips/code-generator-mips.cc
@@ -154,7 +154,7 @@ void CodeGenerator::AssembleArchInstruction(Instruction* instr) {
       break;
     }
     case kArchJmp:
-      __ Branch(code_->GetLabel(i.InputBlock(0)));
+      __ Branch(code_->GetLabel(i.InputRpo(0)));
       break;
     case kArchNop:
       // don't emit code for nops.
@@ -393,8 +393,10 @@ void CodeGenerator::AssembleArchBranch(Instruction* instr,
 
   // Emit a branch. The true and false targets are always the last two inputs
   // to the instruction.
-  BasicBlock* tblock = i.InputBlock(instr->InputCount() - 2);
-  BasicBlock* fblock = i.InputBlock(instr->InputCount() - 1);
+  BasicBlock::RpoNumber tblock =
+      i.InputRpo(static_cast<int>(instr->InputCount()) - 2);
+  BasicBlock::RpoNumber fblock =
+      i.InputRpo(static_cast<int>(instr->InputCount()) - 1);
   bool fallthru = IsNextInAssemblyOrder(fblock);
   Label* tlabel = code()->GetLabel(tblock);
   Label* flabel = fallthru ? &done : code()->GetLabel(fblock);