icicle/examples/c++/msm/README.md

Icicle example: Muli-Scalar Multiplication (MSM)

Key-Takeaway

Icicle provides CUDA C++ template function MSM to accelerate Multi-Scalar Multiplication.

Concise Usage Explanation

1. Include the curve api
2. Configure MSM
3. Call msm api

#include "icicle/api/bn254.h"
...
MSMConfig config = default_msm_config();
...
bn254_msm(scalars, points, size, config, &result);

In this example we use BN254 curve. The function computes result = \sum_{i=0}^{size-1} scalars[i] \cdot points[i], where input points[] use affine coordinates, and result uses projective coordinates.

Parameters:

The configuration is passed to the kernel as a structure of type MSMConfig. Some of the most important fields are listed below:

• are_scalars_on_device, are_points_on_device, are_results_on_device: location of the data

• is_async: blocking vs. non-blocking kernel call

• In addition can pass backend-specific params via config.extConfig. For example CUDA backend accepts a large_bucket_factor param.

Running the example

# for CPU
./run.sh -d CPU
# for CUDA
./run.sh -d CUDA -b /path/to/cuda/backend/install/dir

What's in the example

1. Define the parameters of MSM
2. Generate random inputs on-host
3. Configure and execute MSM using on-host data
4. Copy inputs on-device
5. Configure and execute MSM using on-device data
6. Repeat step 3 G2 msm points