tree 4fed856723fff7404c853f6b5f08088ec78152e4
parent 63152fd929265b73195492e64b29352e1d068287
author David 'Digit' Turner <digit@android.com> 1308144804 +0200
committer David 'Digit' Turner <digit@google.com> 1310075210 +0200

emulator: Build emulator platform images as ARMv7-A

Backport from AOSP master.

Now that the emulator supports proper ARMv7 emulation, switch to
building all emulator-specific platform images using this instruction
set, in order to benefit from the noticeable speed boost provided by
Thumb-2 instructions.

Note that we don't build with NEON support because emulated NEON
instructions are currently slow, though they work.

IMPORTANT: You need to have the following emulator patch in your tree
           in order to start these platform builds easily:

           https://review.source.android.com//#change,23798

Otherwise, the alternative is to do these things:

   1/ Telling the emulator to emulate an ARMv7-A CPU, instead of
      an ARMv5TE one. This is normally done with "-qemu cortex-a8"

   2/ Using an ARMv7-A capable kernel image, which is available and
      usable with -kernel prebuilt/android-arm/kernel-qemu-armv7

Note that the emulator has a special hack that automatically enables
1/ if 2/ is being used (i.e. if the kernel image name ends with -armv7,
then emulate an ARMv7-A CPU automatically).

So in reality, only 2/ is required.

Change-Id: Id3ac7cdbda892e519af98aff1f02136f344406b8
Orig-Change-Id: I5c0245ba5e6a2bc34d0d49b2c024fffd317a5eed