Remove FunctionType (#2510)

Function signatures were previously redundantly stored on Function
objects as well as on FunctionType objects. These two signature
representations had to always be kept in sync, which was error-prone
and needlessly complex. This PR takes advantage of the new ability of
Type to represent multiple value types by consolidating function
signatures as a pair of Types (params and results) stored on the
Function object.

Since there are no longer module-global named function types,
significant changes had to be made to the printing and emitting of
function types, as well as their parsing and manipulation in various
passes.

The C and JS APIs and their tests also had to be updated to remove
named function types.

Author: tlively

CHANGELOG.md

@@ -27,6 +27,9 @@ Current Trunk
 - Replace BinaryenSIMDBitselect* with BinaryenSIMDTernary* in the C API and add
   qfma/qfms instructions.
 - Added `offset` parameter to BinaryenSetFunctionTable.
+- Add the ability to create multivalue Types in the C and JS APIs.
+- Remove named function types. They are replaced by `params` and `results` types
+  local to each function.
 
 v88
 ---

scripts/clean_c_api_trace.py

@@ -22,8 +22,9 @@
 trace = open(sys.argv[1]).read()
 
 start = trace.find('// beginning a Binaryen API trace')
+end = trace.rfind('// ending a Binaryen API trace')
 if start >= 0:
-    trace = trace[start:]
+    trace = trace[start:end]
 
     while 1:
         start = trace.find('\n(')

src/abi/js.h

@@ -52,22 +52,20 @@ extern cashew::IString SCRATCH_STORE_F64;
 inline void
 ensureScratchMemoryHelpers(Module* wasm,
                            cashew::IString specific = cashew::IString()) {
-  auto ensureImport =
-    [&](Name name, const std::vector<Type> params, Type result) {
-      if (wasm->getFunctionOrNull(name)) {
-        return;
-      }
-      if (specific.is() && name != specific) {
-        return;
-      }
-      auto func = make_unique<Function>();
-      func->name = name;
-      func->params = params;
-      func->result = result;
-      func->module = ENV;
-      func->base = name;
-      wasm->addFunction(std::move(func));
-    };
+  auto ensureImport = [&](Name name, Type params, Type results) {
+    if (wasm->getFunctionOrNull(name)) {
+      return;
+    }
+    if (specific.is() && name != specific) {
+      return;
+    }
+    auto func = make_unique<Function>();
+    func->name = name;
+    func->sig = Signature(params, results);
+    func->module = ENV;
+    func->base = name;
+    wasm->addFunction(std::move(func));
+  };
 
   ensureImport(SCRATCH_LOAD_I32, {i32}, i32);
   ensureImport(SCRATCH_STORE_I32, {i32, i32}, none);

src/abi/stack.h

@@ -128,10 +128,10 @@ getStackSpace(Index local, Function* func, Index size, Module& wasm) {
     // no need to restore the old stack value, we're gone anyhow
   } else {
     // save the return value
-    auto temp = builder.addVar(func, func->result);
+    auto temp = builder.addVar(func, func->sig.results);
     block->list.push_back(builder.makeLocalSet(temp, func->body));
     block->list.push_back(makeStackRestore());
-    block->list.push_back(builder.makeLocalGet(temp, func->result));
+    block->list.push_back(builder.makeLocalGet(temp, func->sig.results));
   }
   block->finalize();
   func->body = block;