wasm2js: Add Table operations (#6650)

TableGet, Set, Size, Grow, Fill, Copy.

Also move "null" into shared-constants, to make the code
more consistent overall.

7 files changed, 298 insertions, 17 deletions

diff --git a/src/abi/js.h b/src/abi/js.h
index e121e9b28..b8f56f14d 100644
--- a/src/abi/js.h
+++ b/src/abi/js.h
@@ -36,6 +36,9 @@ extern IString SCRATCH_STORE_F64;
 extern IString MEMORY_INIT;
 extern IString MEMORY_FILL;
 extern IString MEMORY_COPY;
+extern IString TABLE_GROW;
+extern IString TABLE_FILL;
+extern IString TABLE_COPY;
 extern IString DATA_DROP;
 extern IString ATOMIC_WAIT_I32;
 extern IString ATOMIC_RMW_I64;
@@ -81,6 +84,13 @@ inline void ensureHelpers(Module* wasm, IString specific = IString()) {
     Type::i32);
   ensureImport(GET_STASHED_BITS, {}, Type::i32);
   ensureImport(TRAP, {}, Type::none);
+
+  if (wasm->features.hasReferenceTypes()) {
+    auto funcref = Type(HeapType::func, Nullable);
+    ensureImport(TABLE_GROW, {funcref, Type::i32}, Type::none);
+    ensureImport(TABLE_FILL, {Type::i32, funcref, Type::i32}, Type::none);
+    ensureImport(TABLE_COPY, {Type::i32, Type::i32, Type::i32}, Type::none);
+  }
 }
 
 inline bool isHelper(IString name) {
@@ -88,7 +98,8 @@ inline bool isHelper(IString name) {
          name == SCRATCH_LOAD_F32 || name == SCRATCH_STORE_F32 ||
          name == SCRATCH_LOAD_F64 || name == SCRATCH_STORE_F64 ||
          name == ATOMIC_WAIT_I32 || name == MEMORY_INIT ||
-         name == MEMORY_FILL || name == MEMORY_COPY || name == DATA_DROP ||
+         name == MEMORY_FILL || name == MEMORY_COPY || name == TABLE_GROW ||
+         name == TABLE_FILL || name == TABLE_COPY || name == DATA_DROP ||
          name == ATOMIC_RMW_I64 || name == GET_STASHED_BITS || name == TRAP;
 }
 
diff --git a/src/asmjs/shared-constants.cpp b/src/asmjs/shared-constants.cpp
index 57b9c4f87..bd924f179 100644
--- a/src/asmjs/shared-constants.cpp
+++ b/src/asmjs/shared-constants.cpp
@@ -62,6 +62,7 @@ IString ENV("env");
 IString STACKTOP("STACKTOP");
 IString STACK_MAX("STACK_MAX");
 IString INSTRUMENT("instrument");
+IString LENGTH("length");
 IString MATH_IMUL("Math_imul");
 IString MATH_ABS("Math_abs");
 IString MATH_CEIL("Math_ceil");
@@ -111,6 +112,9 @@ IString SCRATCH_STORE_F64("wasm2js_scratch_store_f64");
 IString MEMORY_INIT("wasm2js_memory_init");
 IString MEMORY_FILL("wasm2js_memory_fill");
 IString MEMORY_COPY("wasm2js_memory_copy");
+IString TABLE_GROW("wasm2js_table_grow");
+IString TABLE_FILL("wasm2js_table_fill");
+IString TABLE_COPY("wasm2js_table_copy");
 IString DATA_DROP("wasm2js_data_drop");
 IString ATOMIC_WAIT_I32("wasm2js_atomic_wait_i32");
 IString ATOMIC_RMW_I64("wasm2js_atomic_rmw_i64");
diff --git a/src/asmjs/shared-constants.h b/src/asmjs/shared-constants.h
index e199b1361..d48da560e 100644
--- a/src/asmjs/shared-constants.h
+++ b/src/asmjs/shared-constants.h
@@ -65,6 +65,7 @@ extern IString ENV;
 extern IString STACKTOP;
 extern IString STACK_MAX;
 extern IString INSTRUMENT;
+extern IString LENGTH;
 extern IString MATH_IMUL;
 extern IString MATH_ABS;
 extern IString MATH_CLZ32;
diff --git a/src/wasm2js.h b/src/wasm2js.h
index 2084c0453..dd4e61a51 100644
--- a/src/wasm2js.h
+++ b/src/wasm2js.h
@@ -672,12 +672,11 @@ void Wasm2JSBuilder::addTable(Ref ast, Module* wasm) {
     if (!table->imported()) {
       TableUtils::FlatTable flat(*wasm, *table);
       if (flat.valid) {
-        Name null("null");
         for (auto& name : flat.names) {
           if (name.is()) {
             name = fromName(name, NameScope::Top);
           } else {
-            name = null;
+            name = NULL_;
           }
           ValueBuilder::appendToArray(theArray, ValueBuilder::makeName(name));
         }
@@ -2221,11 +2220,11 @@ Ref Wasm2JSBuilder::processFunctionBody(Module* m,
                                     visit(curr->value, EXPRESSION_RESULT),
                                     visit(curr->size, EXPRESSION_RESULT));
     }
-    Ref visitRefNull(RefNull* curr) { return ValueBuilder::makeName("null"); }
+    Ref visitRefNull(RefNull* curr) { return ValueBuilder::makeName(NULL_); }
     Ref visitRefIsNull(RefIsNull* curr) {
       return ValueBuilder::makeBinary(visit(curr->value, EXPRESSION_RESULT),
                                       EQ,
-                                      ValueBuilder::makeName("null"));
+                                      ValueBuilder::makeName(NULL_));
     }
     Ref visitRefFunc(RefFunc* curr) {
       return ValueBuilder::makeName(fromName(curr->func, NameScope::Top));
@@ -2236,28 +2235,40 @@ Ref Wasm2JSBuilder::processFunctionBody(Module* m,
                                       visit(curr->right, EXPRESSION_RESULT));
     }
     Ref visitTableGet(TableGet* curr) {
-      unimplemented(curr);
-      WASM_UNREACHABLE("unimp");
+      return ValueBuilder::makeSub(ValueBuilder::makeName(FUNCTION_TABLE),
+                                   visit(curr->index, EXPRESSION_RESULT));
     }
     Ref visitTableSet(TableSet* curr) {
-      unimplemented(curr);
-      WASM_UNREACHABLE("unimp");
+      auto sub = ValueBuilder::makeSub(ValueBuilder::makeName(FUNCTION_TABLE),
+                                       visit(curr->index, EXPRESSION_RESULT));
+      auto value = visit(curr->value, EXPRESSION_RESULT);
+      return ValueBuilder::makeBinary(sub, SET, value);
     }
     Ref visitTableSize(TableSize* curr) {
-      unimplemented(curr);
-      WASM_UNREACHABLE("unimp");
+      return ValueBuilder::makeDot(ValueBuilder::makeName(FUNCTION_TABLE),
+                                   ValueBuilder::makeName(LENGTH));
     }
     Ref visitTableGrow(TableGrow* curr) {
-      unimplemented(curr);
-      WASM_UNREACHABLE("unimp");
+      ABI::wasm2js::ensureHelpers(module, ABI::wasm2js::TABLE_GROW);
+      // Also ensure fill, as grow calls fill internally.
+      ABI::wasm2js::ensureHelpers(module, ABI::wasm2js::TABLE_FILL);
+      return ValueBuilder::makeCall(ABI::wasm2js::TABLE_GROW,
+                                    visit(curr->value, EXPRESSION_RESULT),
+                                    visit(curr->delta, EXPRESSION_RESULT));
     }
     Ref visitTableFill(TableFill* curr) {
-      unimplemented(curr);
-      WASM_UNREACHABLE("unimp");
+      ABI::wasm2js::ensureHelpers(module, ABI::wasm2js::TABLE_FILL);
+      return ValueBuilder::makeCall(ABI::wasm2js::TABLE_FILL,
+                                    visit(curr->dest, EXPRESSION_RESULT),
+                                    visit(curr->value, EXPRESSION_RESULT),
+                                    visit(curr->size, EXPRESSION_RESULT));
     }
     Ref visitTableCopy(TableCopy* curr) {
-      unimplemented(curr);
-      WASM_UNREACHABLE("unimp");
+      ABI::wasm2js::ensureHelpers(module, ABI::wasm2js::TABLE_COPY);
+      return ValueBuilder::makeCall(ABI::wasm2js::TABLE_COPY,
+                                    visit(curr->dest, EXPRESSION_RESULT),
+                                    visit(curr->source, EXPRESSION_RESULT),
+                                    visit(curr->size, EXPRESSION_RESULT));
     }
     Ref visitTry(Try* curr) {
       unimplemented(curr);
@@ -3026,6 +3037,36 @@ void Wasm2JSGlue::emitSpecialSupport() {
     bufferView.copyWithin(dest, source, source + size);
   }
       )";
+    } else if (import->base == ABI::wasm2js::TABLE_GROW) {
+      out << R"(
+  function wasm2js_table_grow(value, delta) {
+    // TODO: traps on invalid things
+    var oldSize = FUNCTION_TABLE.length;
+    FUNCTION_TABLE.length = oldSize + delta;
+    if (newSize > oldSize) {
+      __wasm_table_fill(oldSize, value, delta)
+    }
+    return oldSize;
+  }
+      )";
+    } else if (import->base == ABI::wasm2js::TABLE_FILL) {
+      out << R"(
+  function __wasm_table_fill(dest, value, size) {
+    // TODO: traps on invalid things
+    for (var i = 0; i < size; i++) {
+      FUNCTION_TABLE[dest + i] = value;
+    }
+  }
+      )";
+    } else if (import->base == ABI::wasm2js::TABLE_COPY) {
+      out << R"(
+  function __wasm_table_copy(dest, source, size) {
+    // TODO: traps on invalid things
+    for (var i = 0; i < size; i++) {
+      FUNCTION_TABLE[dest + i] = FUNCTION_TABLE[source + i];
+    }
+  }
+      )";
     } else if (import->base == ABI::wasm2js::DATA_DROP) {
       out << R"(
   function wasm2js_data_drop(segment) {
diff --git a/test/wasm2js/tables.2asm.js b/test/wasm2js/tables.2asm.js
new file mode 100644
index 000000000..a7dd8fdd5
--- /dev/null
+++ b/test/wasm2js/tables.2asm.js
@@ -0,0 +1,89 @@
+import * as env from 'env';
+
+
+  function wasm2js_table_grow(value, delta) {
+    // TODO: traps on invalid things
+    var oldSize = FUNCTION_TABLE.length;
+    FUNCTION_TABLE.length = oldSize + delta;
+    if (newSize > oldSize) {
+      __wasm_table_fill(oldSize, value, delta)
+    }
+    return oldSize;
+  }
+      
+  function __wasm_table_fill(dest, value, size) {
+    // TODO: traps on invalid things
+    for (var i = 0; i < size; i++) {
+      FUNCTION_TABLE[dest + i] = value;
+    }
+  }
+      
+  function __wasm_table_copy(dest, source, size) {
+    // TODO: traps on invalid things
+    for (var i = 0; i < size; i++) {
+      FUNCTION_TABLE[dest + i] = FUNCTION_TABLE[source + i];
+    }
+  }
+      
+function asmFunc(imports) {
+ var env = imports.env;
+ var FUNCTION_TABLE = env.table;
+ var Math_imul = Math.imul;
+ var Math_fround = Math.fround;
+ var Math_abs = Math.abs;
+ var Math_clz32 = Math.clz32;
+ var Math_min = Math.min;
+ var Math_max = Math.max;
+ var Math_floor = Math.floor;
+ var Math_ceil = Math.ceil;
+ var Math_trunc = Math.trunc;
+ var Math_sqrt = Math.sqrt;
+ function table_get() {
+  return FUNCTION_TABLE[1];
+ }
+ 
+ function table_set() {
+  FUNCTION_TABLE[1] = table_set;
+ }
+ 
+ function table_size() {
+  return FUNCTION_TABLE.length | 0;
+ }
+ 
+ function table_grow() {
+  return wasm2js_table_grow(table_grow, 42) | 0;
+ }
+ 
+ function table_fill(dest, value, size) {
+  dest = dest | 0;
+  size = size | 0;
+  wasm2js_table_fill(dest, value, size);
+ }
+ 
+ function table_copy(dest, source, size) {
+  dest = dest | 0;
+  source = source | 0;
+  size = size | 0;
+  wasm2js_table_copy(dest, source, size);
+ }
+ 
+ FUNCTION_TABLE[1] = table_get;
+ return {
+  "table_get": table_get, 
+  "table_set": table_set, 
+  "table_size": table_size, 
+  "table_grow": table_grow, 
+  "table_fill": table_fill, 
+  "table_copy": table_copy
+ };
+}
+
+var retasmFunc = asmFunc({
+  "env": env,
+});
+export var table_get = retasmFunc.table_get;
+export var table_set = retasmFunc.table_set;
+export var table_size = retasmFunc.table_size;
+export var table_grow = retasmFunc.table_grow;
+export var table_fill = retasmFunc.table_fill;
+export var table_copy = retasmFunc.table_copy;
diff --git a/test/wasm2js/tables.2asm.js.opt b/test/wasm2js/tables.2asm.js.opt
new file mode 100644
index 000000000..f15b0cb11
--- /dev/null
+++ b/test/wasm2js/tables.2asm.js.opt
@@ -0,0 +1,89 @@
+import * as env from 'env';
+
+
+  function wasm2js_table_grow(value, delta) {
+    // TODO: traps on invalid things
+    var oldSize = FUNCTION_TABLE.length;
+    FUNCTION_TABLE.length = oldSize + delta;
+    if (newSize > oldSize) {
+      __wasm_table_fill(oldSize, value, delta)
+    }
+    return oldSize;
+  }
+      
+  function __wasm_table_fill(dest, value, size) {
+    // TODO: traps on invalid things
+    for (var i = 0; i < size; i++) {
+      FUNCTION_TABLE[dest + i] = value;
+    }
+  }
+      
+  function __wasm_table_copy(dest, source, size) {
+    // TODO: traps on invalid things
+    for (var i = 0; i < size; i++) {
+      FUNCTION_TABLE[dest + i] = FUNCTION_TABLE[source + i];
+    }
+  }
+      
+function asmFunc(imports) {
+ var env = imports.env;
+ var FUNCTION_TABLE = env.table;
+ var Math_imul = Math.imul;
+ var Math_fround = Math.fround;
+ var Math_abs = Math.abs;
+ var Math_clz32 = Math.clz32;
+ var Math_min = Math.min;
+ var Math_max = Math.max;
+ var Math_floor = Math.floor;
+ var Math_ceil = Math.ceil;
+ var Math_trunc = Math.trunc;
+ var Math_sqrt = Math.sqrt;
+ function table_get() {
+  return FUNCTION_TABLE[1];
+ }
+ 
+ function table_set() {
+  FUNCTION_TABLE[1] = table_set;
+ }
+ 
+ function table_size() {
+  return FUNCTION_TABLE.length | 0;
+ }
+ 
+ function table_grow() {
+  return wasm2js_table_grow(table_grow, 42) | 0;
+ }
+ 
+ function table_fill($0, $1, $2) {
+  $0 = $0 | 0;
+  $2 = $2 | 0;
+  wasm2js_table_fill($0, $1, $2);
+ }
+ 
+ function table_copy($0, $1, $2) {
+  $0 = $0 | 0;
+  $1 = $1 | 0;
+  $2 = $2 | 0;
+  wasm2js_table_copy($0, $1, $2);
+ }
+ 
+ FUNCTION_TABLE[1] = table_get;
+ return {
+  "table_get": table_get, 
+  "table_set": table_set, 
+  "table_size": table_size, 
+  "table_grow": table_grow, 
+  "table_fill": table_fill, 
+  "table_copy": table_copy
+ };
+}
+
+var retasmFunc = asmFunc({
+  "env": env,
+});
+export var table_get = retasmFunc.table_get;
+export var table_set = retasmFunc.table_set;
+export var table_size = retasmFunc.table_size;
+export var table_grow = retasmFunc.table_grow;
+export var table_fill = retasmFunc.table_fill;
+export var table_copy = retasmFunc.table_copy;
diff --git a/test/wasm2js/tables.wast b/test/wasm2js/tables.wast
new file mode 100644
index 000000000..56e85e40d
--- /dev/null
+++ b/test/wasm2js/tables.wast
@@ -0,0 +1,46 @@
+(module
+  (import "env" "table" (table $table 7 funcref))
+
+  (elem (i32.const 1) $table.get)
+
+  (func $table.get (export "table.get") (result funcref)
+    (table.get $table
+      (i32.const 1)
+    )
+  )
+
+  (func $table.set (export "table.set")
+    (table.set $table
+      (i32.const 1)
+      (ref.func $table.set)
+    )
+  )
+
+  (func $table.size (export "table.size") (result i32)
+    (table.size $table)
+  )
+
+  (func $table.grow (export "table.grow") (result i32)
+    (table.grow $table
+      (ref.func $table.grow)
+      (i32.const 42)
+    )
+  )
+
+  (func $table.fill (export "table.fill") (param $dest i32) (param $value funcref) (param $size i32)
+    (table.fill $table
+      (local.get $dest)
+      (local.get $value)
+      (local.get $size)
+    )
+  )
+
+  (func $table.copy (export "table.copy") (param $dest i32) (param $source i32) (param $size i32)
+    (table.copy $table $table
+      (local.get $dest)
+      (local.get $source)
+      (local.get $size)
+    )
+  )
+)
+