Merge #424

424: Update emscripten to run JSC r=syrusakbary a=MarkMcCaskey



Co-authored-by: Mark McCaskey <mark@wasmer.io>

lib/emscripten/src/lib.rs

@@ -50,7 +50,7 @@ mod varargs;
 
 pub use self::storage::{align_memory, static_alloc};
 pub use self::utils::{
-    allocate_cstr_on_stack, allocate_on_stack, get_emscripten_memory_size,
+    allocate_cstr_on_stack, allocate_on_stack, get_emscripten_memory_size, get_emscripten_metadata,
     get_emscripten_table_size, is_emscripten_module,
 };
 
@@ -301,7 +301,6 @@ pub fn run_emscripten_instance(
 
     if let Some(ep) = entrypoint {
         debug!("Running entry point: {}", &ep);
-        let ep_fn = instance.dyn_func(&ep)?;
         let arg = unsafe { allocate_cstr_on_stack(instance.context_mut(), args[0]).0 };
         //let (argc, argv) = store_module_arguments(instance.context_mut(), args);
         instance.call(&ep, &[Value::I32(arg as i32)])?;
@@ -351,9 +350,7 @@ fn store_module_arguments(ctx: &mut Ctx, args: Vec<&str>) -> (u32, u32) {
 
 pub fn emscripten_set_up_memory(memory: &Memory, globals: &EmscriptenGlobalsData) {
     let dynamictop_ptr = globals.dynamictop_ptr;
-    let stack_max = globals.stack_max;
-
-    let dynamic_base = align_memory(stack_max);
+    let dynamic_base = globals.dynamic_base;
 
     memory.view::<u32>()[(dynamictop_ptr / 4) as usize].set(dynamic_base);
 }
@@ -364,6 +361,7 @@ pub struct EmscriptenGlobalsData {
     stacktop: u32,
     stack_max: u32,
     dynamictop_ptr: u32,
+    dynamic_base: u32,
     memory_base: u32,
     table_base: u32,
     temp_double_ptr: u32,
@@ -433,7 +431,14 @@ impl EmscriptenGlobals {
             let temp_double_ptr = static_top;
             static_top += 16;
 
-            let dynamictop_ptr = static_alloc(&mut static_top, 4);
+            let (dynamic_base, dynamictop_ptr) =
+                get_emscripten_metadata(&module).unwrap_or_else(|| {
+                    let dynamictop_ptr = static_alloc(&mut static_top, 4);
+                    (
+                        align_memory(align_memory(static_top) + TOTAL_STACK),
+                        dynamictop_ptr,
+                    )
+                });
 
             let stacktop = align_memory(static_top);
             let stack_max = stacktop + TOTAL_STACK;
@@ -443,6 +448,7 @@ impl EmscriptenGlobals {
                 stacktop,
                 stack_max,
                 dynamictop_ptr,
+                dynamic_base,
                 memory_base,
                 table_base,
                 temp_double_ptr,

lib/emscripten/src/syscalls/mod.rs

@@ -127,14 +127,12 @@ pub fn ___syscall38(ctx: &mut Ctx, _which: c_int, mut varargs: VarArgs) -> i32 {
     let old_path = emscripten_memory_pointer!(ctx.memory(0), old_path_addr) as *const i8;
     let new_path = emscripten_memory_pointer!(ctx.memory(0), new_path_addr) as *const i8;
     let result = unsafe { rename(old_path, new_path) };
-    unsafe {
-        debug!(
-            "=> old_path: {}, new_path: {}, result: {}",
-            std::ffi::CStr::from_ptr(old_path).to_str().unwrap(),
-            std::ffi::CStr::from_ptr(new_path).to_str().unwrap(),
-            result
-        );
-    }
+    debug!(
+        "=> old_path: {}, new_path: {}, result: {}",
+        std::ffi::CStr::from_ptr(old_path).to_str().unwrap(),
+        std::ffi::CStr::from_ptr(new_path).to_str().unwrap(),
+        result
+    );
     result
 }
 
@@ -274,7 +272,6 @@ pub fn ___syscall192(ctx: &mut Ctx, _which: c_int, mut varargs: VarArgs) -> c_in
         debug!("=> ptr: {}", ptr);
         return ptr as i32;
     } else {
-        unimplemented!("temp during dev");
         // return ENODEV
         return -19;
     }
@@ -487,7 +484,7 @@ pub fn ___syscall300(_ctx: &mut Ctx, _one: i32, _two: i32) -> i32 {
 }
 
 // utimensat
-pub fn ___syscall320(ctx: &mut Ctx, _which: c_int, mut _varargs: VarArgs) -> c_int {
+pub fn ___syscall320(_ctx: &mut Ctx, _which: c_int, mut _varargs: VarArgs) -> c_int {
     debug!("emscripten::___syscall320 (utimensat), {}", _which);
     0
 }

lib/emscripten/src/time.rs

@@ -28,7 +28,9 @@ use wasmer_runtime_core::vm::Ctx;
 use libc::{CLOCK_MONOTONIC, CLOCK_MONOTONIC_COARSE, CLOCK_REALTIME};
 
 #[cfg(target_os = "macos")]
-use libc::{CLOCK_MONOTONIC, CLOCK_REALTIME};
+use libc::CLOCK_REALTIME;
+#[cfg(target_os = "macos")]
+const CLOCK_MONOTONIC: clockid_t = 1;
 #[cfg(target_os = "macos")]
 const CLOCK_MONOTONIC_COARSE: clockid_t = 6;
 

lib/emscripten/src/utils.rs

@@ -1,5 +1,6 @@
 use super::env;
 use super::env::get_emscripten_data;
+use crate::storage::align_memory;
 use libc::stat;
 use std::ffi::CStr;
 use std::mem::size_of;
@@ -39,6 +40,43 @@ pub fn get_emscripten_memory_size(module: &Module) -> (Pages, Option<Pages>) {
     (memory.minimum, memory.maximum)
 }
 
+/// Reads values written by `-s EMIT_EMSCRIPTEN_METADATA=1`
+/// Assumes values start from the end in this order:
+/// Last export: Dynamic Base
+/// Second-to-Last export: Dynamic top pointer
+pub fn get_emscripten_metadata(module: &Module) -> Option<(u32, u32)> {
+    let max_idx = &module.info().globals.iter().map(|(k, _)| k).max()?;
+    let snd_max_idx = &module
+        .info()
+        .globals
+        .iter()
+        .map(|(k, _)| k)
+        .filter(|k| k != max_idx)
+        .max()?;
+
+    use wasmer_runtime_core::types::{GlobalInit, Initializer::Const, Value::I32};
+    if let (
+        GlobalInit {
+            init: Const(I32(dynamic_base)),
+            ..
+        },
+        GlobalInit {
+            init: Const(I32(dynamictop_ptr)),
+            ..
+        },
+    ) = (
+        &module.info().globals[*max_idx],
+        &module.info().globals[*snd_max_idx],
+    ) {
+        Some((
+            align_memory(*dynamic_base as u32 - 32),
+            align_memory(*dynamictop_ptr as u32 - 32),
+        ))
+    } else {
+        None
+    }
+}
+
 pub unsafe fn write_to_buf(ctx: &mut Ctx, string: *const c_char, buf: u32, max: u32) -> u32 {
     let buf_addr = emscripten_memory_pointer!(ctx.memory(0), buf) as *mut c_char;
 

lib/runtime-core/src/types.rs

@@ -401,7 +401,7 @@ pub trait LocalImport {
 macro_rules! define_map_index {
     ($ty:ident) => {
         #[derive(Serialize, Deserialize)]
-        #[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
+        #[derive(Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
         pub struct $ty (u32);
         impl TypedIndex for $ty {
             #[doc(hidden)]