Add a README

README.md

@@ -0,0 +1,18 @@
+# ZIMD
+
+Additional cross-platform SIMD support for Zig.
+
+Based loosely on [Google Highway](https://github.com/google/highway)
+
+## Why?
+
+Zig has builtin support for SIMD operations using `@Vector`. However this only supports a few
+basic operations. This library aims to fill in some of the blanks.
+
+## Operators
+
+### [TableLookupBytesOr0](https://google.github.io/highway/en/master/quick_reference.html#blockwise)
+
+Architectures: Scalar, X86_SSE3, Arm_Neon
+
+Similar to Zig's `@shuffle` operator, except doesn't require the shuffle mask to be comptime known.

src/tblz.zig

@@ -21,9 +21,11 @@ const builtin = @import("builtin");
 const std = @import("std");
 const zimd = @import("zimd.zig");
 
-const TableLookupBytesOr0 = fn (bytes: @Vector(16, u8), indices: @Vector(16, i8)) callconv(.Inline) @Vector(16, u8);
+pub const TableLookupBytesOr0 = fn (bytes: @Vector(16, u8), indices: @Vector(16, i8)) callconv(.Inline) @Vector(16, u8);
 
-pub fn GetTableLookupBytesOr0(comptime cpu: std.Target.Cpu) TableLookupBytesOr0 {
+pub const tableLookupBytesOr0 = GetTableLookupBytesOr0(builtin.cpu);
+
+fn GetTableLookupBytesOr0(comptime cpu: std.Target.Cpu) TableLookupBytesOr0 {
     if (comptime cpu.arch.isAARCH64() and std.Target.aarch64.featureSetHas(cpu.features, .neon)) {
         return Aarch64_Neon;
     }
@@ -33,8 +35,6 @@ pub fn GetTableLookupBytesOr0(comptime cpu: std.Target.Cpu) TableLookupBytesOr0
     return Scalar;
 }
 
-pub const tableLookupBytesOr0 = GetTableLookupBytesOr0(builtin.cpu);
-
 // For all vector widths; Arm anyway zeroes if >= 0x10.
 inline fn Aarch64_Neon(bytes: @Vector(16, u8), indices: @Vector(16, i8)) @Vector(16, u8) {
     return asm ("tbl.16b %[ret], { %[v0] }, %[v1]"