add simd example

examples/rust/simd/Cargo.toml

@@ -0,0 +1,10 @@
+[package]
+name = "simd"
+version = "0.1.0"
+edition = "2018"
+
+[dependencies]
+wit-bindgen-rust = { git = "https://github.com/bytecodealliance/wit-bindgen.git" }
+
+[lib]
+crate-type = ["cdylib"]

examples/rust/simd/README.md

@@ -0,0 +1,25 @@
+# Simd Rust
+
+A simple simd example using [core::arch::wasm32](https://doc.rust-lang.org/core/arch/wasm32/index.html#simd)
+
+## Build
+
+```sh
+cargo build --target wasm32-unknown-unknown
+```
+
+## Create Function
+
+```sql
+CREATE FUNCTION mul AS WASM FROM INFILE 'target/wasm32-unknown-unknown/debug/simd.wasm' WITH WIT FROM INFILE 'simd.wit'
+CREATE FUNCTION dot AS WASM FROM INFILE 'target/wasm32-unknown-unknown/debug/simd.wasm' WITH WIT FROM INFILE 'simd.wit'
+CREATE FUNCTION `inner` RETURNS TABLE AS WASM FROM INFILE 'target/wasm32-unknown-unknown/debug/simd.wasm' WITH WIT FROM INFILE 'simd.wit'
+```
+
+## Example Queries
+
+```sql
+SELECT mul(3,4);
+SELECT dot([1,2,3], [0,5,6]);
+SELECT * FROM `inner`([1,2,3], [3,4,5]);
+```

examples/rust/simd/simd.wit

@@ -0,0 +1,4 @@
+mul: func(a: u64, b: u64) -> u64
+dot: func(a: list<u64>, b: list<u64>) -> u64
+inner: func(a: list<u64>, b: list<u64>) -> list<u64>
+mmul: func(a: list<list<u64>>, b: list<list<u64>>) -> list<list<u64>>

examples/rust/simd/src/lib.rs

@@ -0,0 +1,47 @@
+#[cfg(target_arch = "wasm32")]
+wit_bindgen_rust::export!("simd.wit");
+
+struct Simd;
+
+use core::arch::wasm32::*;
+
+impl simd::Simd for Simd {
+    fn mul(a: u64, b: u64) -> u64 {
+        let va: v128 = u64x2_splat(a);
+        let vb: v128 = u64x2_splat(b);
+        let c = u64x2_extract_lane::<1>(i64x2_mul(va, vb));
+        c
+    }
+    fn dot(a: Vec<u64>, b: Vec<u64>) -> u64 {
+        assert!(a.len() == b.len());
+        let mut sum: u64 = 0;
+        for i in 0..a.len() {
+            sum += Self::mul(a[i], b[i]);
+        }
+        sum
+    }
+    fn inner(a: Vec<u64>, b: Vec<u64>) -> Vec<u64> {
+        assert!(a.len() == b.len());
+        let mut res = vec![0; a.len()];
+        for i in 0..a.len() {
+            res[i] = Self::mul(a[i], b[i]);
+        }
+        res
+    }
+    fn mmul(a: Vec<Vec<u64>>, b: Vec<Vec<u64>>) -> Vec<Vec<u64>> {
+        if a.len() == 0 && b.len() == 0 {
+            return Vec::with_capacity(0);
+        }
+        assert!(a[0].len() == b.len());
+
+        let mut res = vec![vec![0; a.len()]; b[0].len()];
+        for i in 0..a.len() {
+            for j in 0..b[0].len() {
+                for k in 0..b.len() {
+                    res[i][j] += Self::mul(a[i][k], b[k][j]);
+                }
+            }
+        }
+        res
+    }
+}