From: Chris Duncan <chris@zoso.dev>
Date: Sat, 4 Jan 2025 09:22:26 +0000 (-0800)
Subject: Pass in random data to initialize nonce.
X-Git-Url: https://zoso.dev/?a=commitdiff_plain;h=42383e249b4f3b6b5673f7a34e9cb7b8cfbc7423;p=libnemo.git

Pass in random data to initialize nonce.
---

diff --git a/src/lib/workers/powgpu.ts b/src/lib/workers/powgpu.ts
index c91df86..fd04dbe 100644
--- a/src/lib/workers/powgpu.ts
+++ b/src/lib/workers/powgpu.ts
@@ -44,6 +44,7 @@ export class PowGpu extends WorkerInterface {
 	static #shader = `
 		struct UBO {
 			blockhash: array<vec4<u32>, 2>,
+			random: u32,
 			threshold: u32
 		};
 		@group(0) @binding(0) var<uniform> ubo: UBO;
@@ -138,10 +139,8 @@ export class PowGpu extends WorkerInterface {
 
 		/**
 		* Main compute function
-		*
-		* 8-byte work is split into two 4-byte u32
-		* First 4 bytes will be iterated by shader
-		* Last 4 bytes are defined by index of each thread
+		* 8-byte work is split into two 4-byte u32. Low 4 bytes are random u32 from
+		* UBO. High 4 bytes are the random value XOR'd with index of each thread.
 		*/
 		@compute @workgroup_size(256)
 		fn main(
@@ -156,8 +155,8 @@ export class PowGpu extends WorkerInterface {
 										((workgroup_id.z & 0xff) << 8) |
 										(local_id.x & 0xff);
 			var m: array<u32, 16>;
-			m[0u] = id;
-			m[1u] = reverseBits(id);
+			m[0u] = ubo.random;
+			m[1u] = id ^ ubo.random;
 			m[2u] = ubo.blockhash[0u].x;
 			m[3u] = ubo.blockhash[0u].y;
 			m[4u] = ubo.blockhash[0u].z;
@@ -190,30 +189,27 @@ export class PowGpu extends WorkerInterface {
 			);
 
 			/**
-			* Iterate and hash until nonce found
+			* Twelve rounds of mixing as part of compression step
 			*/
-			for (var j: u32 = 0u; j < 0x1u; j = j + 1u) {
-				m[0u] = m[0u] ^ j;
-
-				// twelve rounds of mixing
-				for (var i: u32 = 0u; i < 12u; i = i + 1u) {
-					G(&v, &m, 0u, 8u, 16u, 24u, SIGMA82[i * 16u + 0u], SIGMA82[i * 16u + 1u]);
-					G(&v, &m, 2u, 10u, 18u, 26u, SIGMA82[i * 16u + 2u], SIGMA82[i * 16u + 3u]);
-					G(&v, &m, 4u, 12u, 20u, 28u, SIGMA82[i * 16u + 4u], SIGMA82[i * 16u + 5u]);
-					G(&v, &m, 6u, 14u, 22u, 30u, SIGMA82[i * 16u + 6u], SIGMA82[i * 16u + 7u]);
-					G(&v, &m, 0u, 10u, 20u, 30u, SIGMA82[i * 16u + 8u], SIGMA82[i * 16u + 9u]);
-					G(&v, &m, 2u, 12u, 22u, 24u, SIGMA82[i * 16u + 10u], SIGMA82[i * 16u + 11u]);
-					G(&v, &m, 4u, 14u, 16u, 26u, SIGMA82[i * 16u + 12u], SIGMA82[i * 16u + 13u]);
-					G(&v, &m, 6u, 8u, 18u, 28u, SIGMA82[i * 16u + 14u], SIGMA82[i * 16u + 15u]);
-				}
+			for (var i: u32 = 0u; i < 12u; i = i + 1u) {
+				G(&v, &m, 0u, 8u, 16u, 24u, SIGMA82[i * 16u + 0u], SIGMA82[i * 16u + 1u]);
+				G(&v, &m, 2u, 10u, 18u, 26u, SIGMA82[i * 16u + 2u], SIGMA82[i * 16u + 3u]);
+				G(&v, &m, 4u, 12u, 20u, 28u, SIGMA82[i * 16u + 4u], SIGMA82[i * 16u + 5u]);
+				G(&v, &m, 6u, 14u, 22u, 30u, SIGMA82[i * 16u + 6u], SIGMA82[i * 16u + 7u]);
+				G(&v, &m, 0u, 10u, 20u, 30u, SIGMA82[i * 16u + 8u], SIGMA82[i * 16u + 9u]);
+				G(&v, &m, 2u, 12u, 22u, 24u, SIGMA82[i * 16u + 10u], SIGMA82[i * 16u + 11u]);
+				G(&v, &m, 4u, 14u, 16u, 26u, SIGMA82[i * 16u + 12u], SIGMA82[i * 16u + 13u]);
+				G(&v, &m, 6u, 8u, 18u, 28u, SIGMA82[i * 16u + 14u], SIGMA82[i * 16u + 15u]);
+			}
 
-				// Store the result directly into work array
-				if (atomicLoad(&work.found) == 0u && (BLAKE2B_IV32_1 ^ v[1u] ^ v[17u]) > ubo.threshold) {
-					atomicStore(&work.found, 1u);
-					work.nonce.x = m[0];
-					work.nonce.y = m[1];
-					return;
-				}
+			/**
+			* Set nonce if it passes the threshold and no other thread has set it
+			*/
+			if (atomicLoad(&work.found) == 0u && (BLAKE2B_IV32_1 ^ v[1u] ^ v[17u]) > ubo.threshold) {
+				atomicStore(&work.found, 1u);
+				work.nonce.x = m[0];
+				work.nonce.y = m[1];
+				return;
 			}
 
 			return;
@@ -300,12 +296,15 @@ export class PowGpu extends WorkerInterface {
 		}
 
 		// Set up uniform buffer object
-		const uboView = new DataView(new ArrayBuffer(48))
+		const uboView = new DataView(new ArrayBuffer(64))
 		for (let i = 0; i < 64; i += 8) {
 			const uint32 = hashHex.slice(i, i + 8)
 			uboView.setUint32(i / 2, parseInt(uint32, 16))
 		}
-		uboView.setUint32(32, threshold, true)
+		const random = crypto.getRandomValues(new Uint32Array(1))[0]
+		console.log(`random: ${random}`)
+		uboView.setUint32(32, random, true)
+		uboView.setUint32(48, threshold, true)
 		const uboBuffer = PowGpu.#device.createBuffer({
 			size: uboView.byteLength,
 			usage: GPUBufferUsage.UNIFORM | GPUBufferUsage.COPY_DST,