Revert "Remove code related to extended-opcode."

This reverts commit 6527b83f7327af4a3919f07054129130e44fdef3.

Change-Id: I782de6800999ce57af8caa50c9900a225ed1fe35

4 files changed, 49 insertions, 6 deletions

diff --git a/dx/src/com/android/dx/command/dexer/Main.java b/dx/src/com/android/dx/command/dexer/Main.java
index d4c396903..ab6d2f788 100644
--- a/dx/src/com/android/dx/command/dexer/Main.java
+++ b/dx/src/com/android/dx/command/dexer/Main.java
@@ -1192,6 +1192,9 @@ public class Main {
          */
         public boolean keepClassesInJar = false;
 
+        /** what API level to target */
+        public int targetApiLevel = DexFormat.API_NO_EXTENDED_OPCODES;
+
         /** how much source position info to preserve */
         public int positionInfo = PositionList.LINES;
 
@@ -1513,6 +1516,7 @@ public class Main {
             cfOptions.warn = DxConsole.err;
 
             dexOptions = new DexOptions();
+            dexOptions.targetApiLevel = targetApiLevel;
             dexOptions.forceJumbo = forceJumbo;
         }
     }
diff --git a/dx/src/com/android/dx/dex/DexOptions.java b/dx/src/com/android/dx/dex/DexOptions.java
index 60d83a84e..db0c7a2c5 100644
--- a/dx/src/com/android/dx/dex/DexOptions.java
+++ b/dx/src/com/android/dx/dex/DexOptions.java
@@ -34,4 +34,12 @@ public class DexOptions {
     public String getMagic() {
         return DexFormat.apiToMagic(targetApiLevel);
     }
+
+    /**
+     * Returns whether extended opcodes are allowed. This became
+     * allowed as of Ice Cream Sandwich.
+     */
+    public boolean canUseExtendedOpcodes() {
+        return targetApiLevel >= DexFormat.API_CURRENT;
+    }
 }
diff --git a/dx/src/com/android/dx/dex/code/Dops.java b/dx/src/com/android/dx/dex/code/Dops.java
index a84ddc098..cc5c173ed 100644
--- a/dx/src/com/android/dx/dex/code/Dops.java
+++ b/dx/src/com/android/dx/dex/code/Dops.java
@@ -1206,15 +1206,29 @@ public final class Dops {
      * the last in its chain
      */
     public static Dop getNextOrNull(Dop opcode, DexOptions options) {
-      int nextOpcode = opcode.getNextOpcode();
+        boolean suppressExtendedOpcodes = !options.canUseExtendedOpcodes();
 
-      if (nextOpcode == Opcodes.NO_NEXT) {
-        return null;
-      }
+        for (;;) {
+            int nextOpcode = opcode.getNextOpcode();
 
-      opcode = get(nextOpcode);
+            if (nextOpcode == Opcodes.NO_NEXT) {
+                return null;
+            }
+
+            opcode = get(nextOpcode);
 
-      return opcode;
+            if (suppressExtendedOpcodes && Opcodes.isExtended(nextOpcode)) {
+                /*
+                 * Continuing rather than just returning null here
+                 * protects against the possibility that an
+                 * instruction fitting chain might list non-extended
+                 * opcodes after extended ones.
+                 */
+                continue;
+            }
+
+            return opcode;
+        }
     }
 
     /**
diff --git a/dx/src/com/android/dx/io/Opcodes.java b/dx/src/com/android/dx/io/Opcodes.java
index 611dbda43..6dba49d9e 100644
--- a/dx/src/com/android/dx/io/Opcodes.java
+++ b/dx/src/com/android/dx/io/Opcodes.java
@@ -327,6 +327,23 @@ public final class Opcodes {
     }
 
     /**
+     * Gets whether ({@code true}) or not ({@code false}) the given
+     * opcode value is an "extended" opcode (not counting the nop-like
+     * payload opcodes). Extended opcodes require a full 16-bit code
+     * unit to represent, without leaving space for an argument byte.
+     * 
+     * @param opcode the opcode value
+     * @return {@code true} iff the opcode is an "extended" opcode
+     */
+    public static boolean isExtended(int opcode) {
+        /*
+         * Note: Extended opcodes all have the form ((byteValue << 8)
+         * | 0xff).
+         */
+        return (opcode >= 0x00ff);
+    }
+
+    /**
      * Gets the opcode out of an opcode unit, the latter of which may also
      * include one or more argument values.
      *