Make local.tee's type its local's type (#2511)

According to the current spec, `local.tee`'s return type should be the
same as its local's type. (Discussions on whether we should change this
rule is going on in WebAssembly/reference-types#55, but here I will
assume this spec does not change. If this changes, we should change many
parts of Binaryen transformation anyway...)

But currently in Binaryen `local.tee`'s type is computed from its
value's type. This didn't make any difference in the MVP, but after we
have subtype relationship in #2451, this can become a problem. For
example:
```
(func $test (result funcref) (local $0 anyref)
  (local.tee $0
    (ref.func $test)
  )
)
```
This shouldn't validate in the spec, but this will pass Binaryen
validation with the current `local.tee` implementation.

This makes `local.tee`'s type computed from the local's type, and makes
`LocalSet::makeTee` get a type parameter, to which we should pass the
its corresponding local's type. We don't embed the local type in the
class `LocalSet` because it may increase memory size.

This also fixes the type of `local.get` to be the local type where
`local.get` and `local.set` pair is created from `local.tee`.

3 files changed, 10 insertions, 5 deletions

diff --git a/test/example/c-api-kitchen-sink.c b/test/example/c-api-kitchen-sink.c
index b3419d184..6284cdd39 100644
--- a/test/example/c-api-kitchen-sink.c
+++ b/test/example/c-api-kitchen-sink.c
@@ -648,7 +648,9 @@ void test_core() {
                                        BinaryenTypeInt32())),
     BinaryenDrop(module, BinaryenLocalGet(module, 0, BinaryenTypeInt32())),
     BinaryenLocalSet(module, 0, makeInt32(module, 101)),
-    BinaryenDrop(module, BinaryenLocalTee(module, 0, makeInt32(module, 102))),
+    BinaryenDrop(
+      module,
+      BinaryenLocalTee(module, 0, makeInt32(module, 102), BinaryenTypeInt32())),
     BinaryenLoad(module, 4, 0, 0, 0, BinaryenTypeInt32(), makeInt32(module, 1)),
     BinaryenLoad(module, 2, 1, 2, 1, BinaryenTypeInt64(), makeInt32(module, 8)),
     BinaryenLoad(
diff --git a/test/example/c-api-kitchen-sink.txt b/test/example/c-api-kitchen-sink.txt
index ca9061e63..a75fd7380 100644
--- a/test/example/c-api-kitchen-sink.txt
+++ b/test/example/c-api-kitchen-sink.txt
@@ -1604,7 +1604,7 @@ int main() {
   expressions[747] = BinaryenConst(the_module, BinaryenLiteralInt32(101));
   expressions[748] = BinaryenLocalSet(the_module, 0, expressions[747]);
   expressions[749] = BinaryenConst(the_module, BinaryenLiteralInt32(102));
-  expressions[750] = BinaryenLocalTee(the_module, 0, expressions[749]);
+  expressions[750] = BinaryenLocalTee(the_module, 0, expressions[749], 2);
   expressions[751] = BinaryenDrop(the_module, expressions[750]);
   expressions[752] = BinaryenConst(the_module, BinaryenLiteralInt32(1));
   expressions[753] = BinaryenLoad(the_module, 4, 0, 0, 0, 2, expressions[752]);
diff --git a/test/example/c-api-relooper-unreachable-if.cpp b/test/example/c-api-relooper-unreachable-if.cpp
index 3b35221ec..329b0e3b7 100644
--- a/test/example/c-api-relooper-unreachable-if.cpp
+++ b/test/example/c-api-relooper-unreachable-if.cpp
@@ -242,7 +242,8 @@ int main() {
   expressions[76] = BinaryenLoad(the_module, 4, 0, 0, 0, BinaryenTypeInt32(), expressions[75]);
   expressions[77] = BinaryenConst(the_module, BinaryenLiteralInt32(128));
   expressions[78] = BinaryenBinary(the_module, 1, expressions[76], expressions[77]);
-  expressions[79] = BinaryenLocalTee(the_module, 3, expressions[78]);
+  expressions[79] =
+    BinaryenLocalTee(the_module, 3, expressions[78], BinaryenTypeInt32());
   expressions[80] = BinaryenStore(
     the_module, 4, 0, 0, expressions[75], expressions[79], BinaryenTypeInt32());
   expressions[81] = BinaryenLocalGet(the_module, 3, BinaryenTypeInt32());
@@ -333,7 +334,8 @@ int main() {
   expressions[123] = BinaryenLoad(the_module, 4, 0, 0, 0, BinaryenTypeInt32(), expressions[122]);
   expressions[124] = BinaryenConst(the_module, BinaryenLiteralInt32(128));
   expressions[125] = BinaryenBinary(the_module, 1, expressions[123], expressions[124]);
-  expressions[126] = BinaryenLocalTee(the_module, 5, expressions[125]);
+  expressions[126] =
+    BinaryenLocalTee(the_module, 5, expressions[125], BinaryenTypeInt32());
   expressions[127] = BinaryenStore(the_module,
                                    4,
                                    0,
@@ -497,7 +499,8 @@ int main() {
   expressions[186] = BinaryenLoad(the_module, 4, 0, 0, 0, BinaryenTypeInt32(), expressions[185]);
   expressions[187] = BinaryenConst(the_module, BinaryenLiteralInt32(128));
   expressions[188] = BinaryenBinary(the_module, 1, expressions[186], expressions[187]);
-  expressions[189] = BinaryenLocalTee(the_module, 6, expressions[188]);
+  expressions[189] =
+    BinaryenLocalTee(the_module, 6, expressions[188], BinaryenTypeInt32());
   expressions[190] = BinaryenStore(the_module,
                                    4,
                                    0,