libsnark-porting

This android-studio project only ported libsnark to arm64. armeabi-v7a(arm32) have some error at prove and verify.

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Elliptic curve choices

use ALT_BN128. more detail https://github.com/scipr-lab/libsnark

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CMake option

vi ~/your-workspace/snarkportingtest/app/build.gradle

• ANDROID_TOOLCHAIN=4.7 : Select compiler version
• _ANDROID_STL=c++shared : If you link library, you need this option
• WITH_PROCPS=OFF : libprocps is not necessary to link the library.
• CURVE=ALT_BN128 : use ALT_BN128
• WITH_SUPERCOP=OFF : supercop is assembly language.(can't use at arm machine)
• OPT_FLAGS=-Os -march=armv8-a : select machine
• PERFORMANCE=ON : OFF DEBUG MODE

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Project Structure

• MINIMUM SDK VERSION : 23(ANDROID 6.0 Marshmallow)
• NDK VERSION : 21.3.6528147
• Android Gradle Plugin Version : 4.0.1
• Gradle Version : 6.1.1