[wasm] Add support for multiple indirect function tables

src/wasm/wasm-interpreter.cc

Index: src/wasm/wasm-interpreter.cc
diff --git a/src/wasm/wasm-interpreter.cc b/src/wasm/wasm-interpreter.cc
index 4d2d994e459db356d3572400f6636f42d4bf4e5d..77099cb51ef0f0d193e97c7cff5200f1561213e9 100644
--- a/src/wasm/wasm-interpreter.cc
+++ b/src/wasm/wasm-interpreter.cc
@@ -915,9 +915,11 @@ class CodeMap {
     return Preprocess(&interpreter_code_[function_index]);
   }
 
-  InterpreterCode* GetIndirectCode(uint32_t indirect_index) {
-    if (indirect_index >= module_->function_table.size()) return nullptr;
-    uint32_t index = module_->function_table[indirect_index];
+  InterpreterCode* GetIndirectCode(uint32_t table_index, uint32_t entry_index) {
+    if (table_index >= module_->function_table.size()) return nullptr;
+    const WasmTable* table = &module_->function_table[table_index];
+    if (entry_index >= table->values.size()) return nullptr;
+    uint32_t index = table->values[entry_index];
     if (index >= interpreter_code_.size()) return nullptr;
     return GetCode(index);
   }
@@ -1383,14 +1385,12 @@ class ThreadImpl : public WasmInterpreter::Thread {
           CallIndirectOperand operand(&decoder, code->at(pc));
           size_t index = stack_.size() - operand.arity - 1;
           DCHECK_LT(index, stack_.size());
-          uint32_t table_index = stack_[index].to<uint32_t>();
-          if (table_index >= module()->function_table.size()) {
+          uint32_t entry_index = stack_[index].to<uint32_t>();
+          // Assume only one table for now.

[ahaas, 2016/07/25 19:23:44]

I think we should have a DCHECK for this assumption.

[ddchen, 2016/07/25 22:17:36]

Done.

+          InterpreterCode* target = codemap()->GetIndirectCode(0, entry_index);
+          if (!target) {
             return DoTrap(kTrapFuncInvalid, pc);
-          }
-          uint16_t function_index = module()->function_table[table_index];
-          InterpreterCode* target = codemap()->GetCode(function_index);
-          DCHECK(target);
-          if (target->function->sig_index != operand.index) {
+          } else if (target->function->sig_index != operand.index) {
             return DoTrap(kTrapFuncSigMismatch, pc);
           }