use std in the runtime

runtime/src/lib.rs

@@ -1,9 +1,5 @@
-#![no_std]
-
-use core::arch::wasm32;
-use core::ptr;
-use core::mem;
-use core::slice;
+use std::mem;
+use std::slice;
 
 pub type ClockyFunc = extern "C" fn(*const Closure) -> *const ();
 
@@ -83,12 +79,6 @@ pub unsafe extern "C" fn since_last_tick_stream(clock: *const Clock) -> *const S
     since_last_tick_closure(clos)
 }
 
-#[cfg(not(test))]
-#[panic_handler]
-fn panic(_: &core::panic::PanicInfo<'_>) -> ! {
-    core::arch::wasm32::unreachable()
-}
-
 #[no_mangle]
 pub extern "C" fn sin(x: f32) -> f32 {
     libm::sinf(x)
@@ -99,31 +89,9 @@ pub extern "C" fn cos(x: f32) -> f32 {
     libm::cosf(x)
 }
 
-static mut HEAP_PTR: *mut () = ptr::null_mut();
-static mut HEAP_END: *mut () = ptr::null_mut();
-
-// ??
-const ALLOC_SIZE_PAGES: usize = 4;
-
 #[no_mangle]
 pub unsafe extern "C" fn alloc(n: u32) -> *mut () {
-    let old_heap_ptr = HEAP_PTR;
-    if let Some(new_heap_ptr) = (HEAP_PTR as usize).checked_add(n as usize) {
-        if new_heap_ptr < HEAP_END as usize {
-            HEAP_PTR = new_heap_ptr as *mut ();
-            old_heap_ptr
-        } else {
-            let old_size = wasm32::memory_grow(0, ALLOC_SIZE_PAGES);
-            if old_size < usize::MAX {
-                let allocation = (old_size * 65536) as *mut ();
-                HEAP_PTR = (old_size * 65536 + n as usize) as *mut ();
-                HEAP_END = ((old_size + ALLOC_SIZE_PAGES) * 65536) as *mut ();
-                allocation
-            } else {
-                panic!()
-            }
-        }
-    } else {
-        panic!()
-    }
+    // TODO: obviously so much. but right now i'm thinking about the
+    // alignment
+    std::alloc::alloc(std::alloc::Layout::from_size_align(n as usize, 4).unwrap()) as *mut ()
 }