Improve infrastructure.

Do more encapsulation of raw pointers, use more PrimaryMaps instead of
Vecs, add a table.rs for managing table storage.

lib/environ/src/compilation.rs

@@ -52,10 +52,10 @@ impl binemit::RelocSink for RelocSink {
         let reloc_target = if let ExternalName::User { namespace, index } = *name {
             debug_assert!(namespace == 0);
             RelocationTarget::UserFunc(FuncIndex::new(index as usize))
-        } else if *name == ExternalName::testcase("grow_memory") {
-            RelocationTarget::GrowMemory
-        } else if *name == ExternalName::testcase("current_memory") {
-            RelocationTarget::CurrentMemory
+        } else if *name == ExternalName::testcase("wasmtime_memory_grow") {
+            RelocationTarget::MemoryGrow
+        } else if *name == ExternalName::testcase("wasmtime_memory_size") {
+            RelocationTarget::MemorySize
         } else {
             panic!("unrecognized external name")
         };
@@ -104,9 +104,9 @@ pub enum RelocationTarget {
     /// The user function index.
     UserFunc(FuncIndex),
     /// Function for growing the default memory by the specified amount of pages.
-    GrowMemory,
+    MemoryGrow,
     /// Function for query current size of the default linear memory.
-    CurrentMemory,
+    MemorySize,
 }
 
 /// Relocations to apply to function bodies.

lib/environ/src/module.rs

@@ -98,7 +98,7 @@ pub struct Module {
     pub signatures: PrimaryMap<SignatureIndex, ir::Signature>,
 
     /// Names of imported functions.
-    pub imported_funcs: Vec<(String, String)>,
+    pub imported_funcs: PrimaryMap<FuncIndex, (String, String)>,
 
     /// Types of functions, imported and local.
     pub functions: PrimaryMap<FuncIndex, SignatureIndex>,
@@ -127,7 +127,7 @@ impl Module {
     pub fn new() -> Self {
         Self {
             signatures: PrimaryMap::new(),
-            imported_funcs: Vec::new(),
+            imported_funcs: PrimaryMap::new(),
             functions: PrimaryMap::new(),
             tables: PrimaryMap::new(),
             memory_plans: PrimaryMap::new(),