src/core: move mach-core@9a4d09707d9f1cb6ea5602bdf58caeefc46146be package to here

Helps hexops/mach#1165

Signed-off-by: Stephen Gutekanst <stephen@hexops.com>

src/core/Timer.zig

@@ -0,0 +1,38 @@
+const std = @import("std");
+const platform = @import("platform.zig");
+
+pub const Timer = @This();
+
+internal: platform.Timer,
+
+/// Initialize the timer.
+pub fn start() !Timer {
+    return Timer{
+        .internal = try platform.Timer.start(),
+    };
+}
+
+/// Reads the timer value since start or the last reset in nanoseconds.
+pub inline fn readPrecise(timer: *Timer) u64 {
+    return timer.internal.read();
+}
+
+/// Reads the timer value since start or the last reset in seconds.
+pub inline fn read(timer: *Timer) f32 {
+    return @as(f32, @floatFromInt(timer.readPrecise())) / @as(f32, @floatFromInt(std.time.ns_per_s));
+}
+
+/// Resets the timer value to 0/now.
+pub inline fn reset(timer: *Timer) void {
+    timer.internal.reset();
+}
+
+/// Returns the current value of the timer in nanoseconds, then resets it.
+pub inline fn lapPrecise(timer: *Timer) u64 {
+    return timer.internal.lap();
+}
+
+/// Returns the current value of the timer in seconds, then resets it.
+pub inline fn lap(timer: *Timer) f32 {
+    return @as(f32, @floatFromInt(timer.lapPrecise())) / @as(f32, @floatFromInt(std.time.ns_per_s));
+}