[interpreter] Bytecode register optimizer.

test/cctest/interpreter/bytecode_expectations/TryCatch.golden

 #
 # Autogenerated by generate-bytecode-expectations.
 #
 
 ---
 pool type: string
 execute: yes
 wrap: yes
 
 ---
 snippet: "
   try { return 1; } catch(e) { return 2; }
 "
 frame size: 5
 parameter count: 1
-bytecode array length: 40
+bytecode array length: 39
 bytecodes: [
   /*   30 E> */ B(StackCheck),
                 B(Mov), R(context), R(1),
   /*   40 S> */ B(LdaSmi), U8(1),
   /*   75 S> */ B(Return),
                 B(Star), R(3),
                 B(LdaConstant), U8(0),
                 B(Star), R(2),
-                B(Ldar), R(closure),
-                B(Star), R(4),
+                B(Mov), R(closure), R(4),
                 B(CallRuntime), U16(Runtime::kPushCatchContext), R(2), U8(3),
                 B(Star), R(1),
                 B(CallRuntime), U16(Runtime::kInterpreterClearPendingMessage), R(0), U8(0),
                 B(Ldar), R(1),
                 B(PushContext), R(0),
   /*   63 S> */ B(LdaSmi), U8(2),
                 B(PopContext), R(0),
   /*   75 S> */ B(Return),
                 B(LdaUndefined),
   /*   75 S> */ B(Return),
 ]
 constant pool: [
   "e",
 ]
 handlers: [
   [4, 7, 7],
 ]
 
 ---
 snippet: "
   var a;
   try { a = 1 } catch(e1) {};
   try { a = 2 } catch(e2) { a = 3 }
 "
 frame size: 6
 parameter count: 1
-bytecode array length: 81
+bytecode array length: 79
 bytecodes: [
   /*   30 E> */ B(StackCheck),
                 B(Mov), R(context), R(2),
   /*   47 S> */ B(LdaSmi), U8(1),
   /*   49 E> */ B(Star), R(0),
-                B(Jump), U8(30),
+                B(Jump), U8(29),
                 B(Star), R(4),
                 B(LdaConstant), U8(0),
                 B(Star), R(3),
-                B(Ldar), R(closure),
-                B(Star), R(5),
+                B(Mov), R(closure), R(5),
                 B(CallRuntime), U16(Runtime::kPushCatchContext), R(3), U8(3),
                 B(Star), R(2),
                 B(CallRuntime), U16(Runtime::kInterpreterClearPendingMessage), R(0), U8(0),
                 B(Ldar), R(2),
                 B(PushContext), R(1),
                 B(PopContext), R(1),
                 B(Mov), R(context), R(2),
   /*   75 S> */ B(LdaSmi), U8(2),
   /*   77 E> */ B(Star), R(0),
-                B(Jump), U8(34),
+                B(Jump), U8(33),
                 B(Star), R(4),
                 B(LdaConstant), U8(1),
                 B(Star), R(3),
-                B(Ldar), R(closure),
-                B(Star), R(5),
+                B(Mov), R(closure), R(5),
                 B(CallRuntime), U16(Runtime::kPushCatchContext), R(3), U8(3),
                 B(Star), R(2),
                 B(CallRuntime), U16(Runtime::kInterpreterClearPendingMessage), R(0), U8(0),
                 B(Ldar), R(2),
                 B(PushContext), R(1),
   /*   95 S> */ B(LdaSmi), U8(3),
   /*   97 E> */ B(Star), R(0),
                 B(PopContext), R(1),
                 B(LdaUndefined),
   /*  103 S> */ B(Return),
 ]
 constant pool: [
   "e1",
   "e2",
 ]
 handlers: [
   [4, 8, 10],
-  [41, 45, 47],
+  [40, 44, 46],
 ]