Use memory min and max values from module to generate environment memory

lib/emscripten/src/lib.rs

@@ -52,7 +52,8 @@ mod varargs;
 
 pub use self::storage::align_memory;
 pub use self::utils::{
-    allocate_cstr_on_stack, allocate_on_stack, get_emscripten_table_size, is_emscripten_module,
+    allocate_cstr_on_stack, allocate_on_stack, get_emscripten_memory_size,
+    get_emscripten_table_size, is_emscripten_module,
 };
 
 // TODO: Magic number - how is this calculated?
@@ -365,14 +366,21 @@ pub struct EmscriptenGlobals {
     pub vm_table: LocalTable,
     pub table_min: u32,
     pub table_max: Option<u32>,
+    pub memory_min: u32,
+    pub memory_max: Option<u32>,
 }
 
 impl EmscriptenGlobals {
-    pub fn new(table_min: u32, table_max: Option<u32>) -> Self {
+    pub fn new(
+        table_min: u32,
+        table_max: Option<u32>,
+        memory_min: u32,
+        memory_max: Option<u32>,
+    ) -> Self {
         // Memory initialization
         let memory_type = Memory {
-            min: 256,
+            min: memory_min,
-            max: Some(256),
+            max: memory_max,
             shared: false,
         };
         let mut memory = LinearMemory::new(&memory_type);
@@ -412,6 +420,8 @@ impl EmscriptenGlobals {
             vm_table,
             table_min,
             table_max,
+            memory_min,
+            memory_max,
         }
     }
 }
@@ -438,8 +448,8 @@ pub fn generate_emscripten_env(globals: &mut EmscriptenGlobals) -> ImportObject
             local: local_memory,
             ctx: null_ctx,
             memory: Memory {
-                min: 256,
+                min: globals.memory_min,
-                max: Some(256),
+                max: globals.memory_max,
                 shared: false,
             },
         },

lib/emscripten/src/utils.rs

@@ -6,7 +6,10 @@ use std::mem::size_of;
 use std::os::raw::c_char;
 use std::slice;
 use wasmer_runtime_core::{
-    module::Module, structures::TypedIndex, types::ImportedTableIndex, vm::Ctx,
+    module::Module,
+    structures::TypedIndex,
+    types::{ImportedMemoryIndex, ImportedTableIndex},
+    vm::Ctx,
 };
 
 /// We check if a provided module is an Emscripten generated one
@@ -24,6 +27,11 @@ pub fn get_emscripten_table_size(module: &Module) -> (u32, Option<u32>) {
     (table.min, table.max)
 }
 
+pub fn get_emscripten_memory_size(module: &Module) -> (u32, Option<u32>) {
+    let (_, memory) = &module.0.imported_memories[ImportedMemoryIndex::new(0)];
+    (memory.min, memory.max)
+}
+
 pub unsafe fn write_to_buf(string: *const c_char, buf: u32, max: u32, ctx: &mut Ctx) -> u32 {
     let buf_addr = emscripten_memory_pointer!(ctx.memory(0), buf) as *mut c_char;
 

lib/emscripten/tests/emtests/_common.rs

@@ -16,7 +16,8 @@ macro_rules! assert_emscripten_output {
 //        let module = compile(&wasm_bytes[..])
 //            .map_err(|err| format!("Can't create the WebAssembly module: {}", err)).unwrap(); // NOTE: Need to figure what the unwrap is for ??
         let (table_min, table_max) = wasmer_emscripten::get_emscripten_table_size(&module);
-        let mut emscripten_globals = EmscriptenGlobals::new(table_min, table_max);
+        let (memory_min, memory_max) = wasmer_emscripten::get_emscripten_memory_size(&module);
+        let mut emscripten_globals = EmscriptenGlobals::new(table_min, table_max, memory_min, memory_max);
         let import_object = generate_emscripten_env(&mut emscripten_globals);
 
         let mut instance = module.instantiate(import_object)

src/bin/wasmer.rs

@@ -71,8 +71,9 @@ fn execute_wasm(options: &Run) -> Result<(), String> {
 
     let (_abi, import_object) = if wasmer_emscripten::is_emscripten_module(&module) {
         let (table_min, table_max) = wasmer_emscripten::get_emscripten_table_size(&module);
+        let (memory_min, memory_max) = wasmer_emscripten::get_emscripten_memory_size(&module);
         let mut emscripten_globals =
-            wasmer_emscripten::EmscriptenGlobals::new(table_min, table_max);
+            wasmer_emscripten::EmscriptenGlobals::new(table_min, table_max, memory_min, memory_max);
         (
             InstanceABI::Emscripten,
             wasmer_emscripten::generate_emscripten_env(&mut emscripten_globals),