[interpreter] Bytecode register optimizer.

test/cctest/interpreter/bytecode_expectations/RemoveRedundantLdar.golden

Index: test/cctest/interpreter/bytecode_expectations/RemoveRedundantLdar.golden
diff --git a/test/cctest/interpreter/bytecode_expectations/RemoveRedundantLdar.golden b/test/cctest/interpreter/bytecode_expectations/RemoveRedundantLdar.golden
index b5ebec19752104efc88fb04dc8b4c3a099c7dfe6..4692b6f52c471f290a3db38910710698d38c8f52 100644
--- a/test/cctest/interpreter/bytecode_expectations/RemoveRedundantLdar.golden
+++ b/test/cctest/interpreter/bytecode_expectations/RemoveRedundantLdar.golden
@@ -16,25 +16,22 @@ snippet: "
   }
   return ld_a;
 "
-frame size: 2
+frame size: 1
 parameter count: 1
-bytecode array length: 31
+bytecode array length: 25
 bytecodes: [
   /*   30 E> */ B(StackCheck),
   /*   45 S> */ B(LdaSmi), U8(1),
   /*   45 E> */ B(Star), R(0),
   /*   48 E> */ B(StackCheck),
   /*   64 S> */ B(Ldar), R(0),
-                B(Star), R(1),
-  /*   78 E> */ B(Ldar), R(0),
-                B(Add), R(1),
+                B(Add), R(0),
   /*   69 E> */ B(Star), R(0),
-  /*   86 S> */ B(Star), R(1),
-                B(LdaSmi), U8(10),
-  /*   95 E> */ B(TestGreaterThan), R(1),
+  /*   86 S> */ B(LdaSmi), U8(10),
+  /*   95 E> */ B(TestGreaterThan), R(0),
                 B(JumpIfFalse), U8(4),
   /*  101 S> */ B(Jump), U8(4),
-                B(Jump), U8(-21),
+                B(Jump), U8(-15),
   /*  110 S> */ B(Ldar), R(0),
   /*  123 S> */ B(Return),
 ]
@@ -52,22 +49,19 @@ snippet: "
   } while(false);
   return ld_a;
 "
-frame size: 2
+frame size: 1
 parameter count: 1
-bytecode array length: 29
+bytecode array length: 23
 bytecodes: [
   /*   30 E> */ B(StackCheck),
   /*   45 S> */ B(LdaSmi), U8(1),
   /*   45 E> */ B(Star), R(0),
   /*   48 E> */ B(StackCheck),
   /*   55 S> */ B(Ldar), R(0),
-                B(Star), R(1),
-  /*   69 E> */ B(Ldar), R(0),
-                B(Add), R(1),
+                B(Add), R(0),
   /*   60 E> */ B(Star), R(0),
-  /*   77 S> */ B(Star), R(1),
-                B(LdaSmi), U8(10),
-  /*   86 E> */ B(TestGreaterThan), R(1),
+  /*   77 S> */ B(LdaSmi), U8(10),
+  /*   86 E> */ B(TestGreaterThan), R(0),
                 B(JumpIfFalse), U8(4),
   /*   92 S> */ B(Jump), U8(2),
   /*  118 S> */ B(Ldar), R(0),
@@ -84,17 +78,16 @@ snippet: "
     ld_a = ld_a + ld_a;
     return ld_a;
 "
-frame size: 2
+frame size: 1
 parameter count: 1
-bytecode array length: 14
+bytecode array length: 12
 bytecodes: [
   /*   30 E> */ B(StackCheck),
   /*   45 S> */ B(LdaSmi), U8(1),
   /*   45 E> */ B(Star), R(0),
-  /*   50 S> */ B(Star), R(1),
-  /*   64 E> */ B(Ldar), R(0),
-                B(Add), R(1),
+  /*   50 S> */ B(Add), R(0),
   /*   55 E> */ B(Star), R(0),
+  /*   72 S> */ B(Ldar), R(0),
   /*   85 S> */ B(Return),
 ]
 constant pool: [