Revert changes to mmtk and memory_manager

Author: wks

src/memory_manager.rs

@@ -494,6 +494,25 @@ pub fn initialize_collection<VM: VMBinding>(mmtk: &'static MMTK<VM>, tls: VMThre
     mmtk.initialize_collection(tls);
 }
 
+/// Process MMTk run-time options. Returns true if the option is processed successfully.
+///
+/// Arguments:
+/// * `mmtk`: A reference to an MMTk instance.
+/// * `name`: The name of the option.
+/// * `value`: The value of the option (as a string).
+pub fn process(builder: &mut MMTKBuilder, name: &str, value: &str) -> bool {
+    builder.set_option(name, value)
+}
+
+/// Process multiple MMTk run-time options. Returns true if all the options are processed successfully.
+///
+/// Arguments:
+/// * `mmtk`: A reference to an MMTk instance.
+/// * `options`: a string that is key value pairs separated by white spaces, e.g. "threads=1 stress_factor=4096"
+pub fn process_bulk(builder: &mut MMTKBuilder, options: &str) -> bool {
+    builder.set_options_bulk_by_str(options)
+}
+
 /// Return used memory in bytes. MMTk accounts for memory in pages, thus this method always returns a value in
 /// page granularity.
 ///

src/mmtk.rs

@@ -75,6 +75,17 @@ impl MMTKBuilder {
         }
     }
 
+    /// Set an option.
+    pub fn set_option(&mut self, name: &str, val: &str) -> bool {
+        self.options.set_by_string(name, val)
+    }
+
+    /// Set multiple options by a string. The string should be key-value pairs separated by white spaces,
+    /// such as `threads=1 stress_factor=4096`.
+    pub fn set_options_bulk_by_str(&mut self, options: &str) -> bool {
+        self.options.bulk_set_by_string(options)
+    }
+
     /// Custom VM layout constants. VM bindings may use this function for compressed or 39-bit heap support.
     /// This function must be called before MMTk::new()
     pub fn set_vm_layout(&mut self, constants: VMLayout) {