add c api method to interpret a module, calling its start method (#601)

4 files changed, 47 insertions, 0 deletions

diff --git a/src/binaryen-c.cpp b/src/binaryen-c.cpp
index 4dff289fb..a9a22ab34 100644
--- a/src/binaryen-c.cpp
+++ b/src/binaryen-c.cpp
@@ -23,9 +23,11 @@
 #include "wasm.h"
 #include "wasm-binary.h"
 #include "wasm-builder.h"
+#include "wasm-interpreter.h"
 #include "wasm-printing.h"
 #include "wasm-validator.h"
 #include "cfg/Relooper.h"
+#include "shell-interface.h"
 
 using namespace wasm;
 
@@ -484,6 +486,12 @@ BinaryenModuleRef BinaryenModuleRead(char* input, size_t inputSize) {
   return wasm;
 }
 
+void BinaryenModuleInterpret(BinaryenModuleRef module) {
+  Module* wasm = (Module*)module;
+  ShellExternalInterface interface;
+  ModuleInstance instance(*wasm, &interface);
+}
+
 //
 // ========== CFG / Relooper ==========
 //
diff --git a/src/binaryen-c.h b/src/binaryen-c.h
index a587e03ac..7403d0e81 100644
--- a/src/binaryen-c.h
+++ b/src/binaryen-c.h
@@ -344,6 +344,11 @@ size_t BinaryenModuleWrite(BinaryenModuleRef module, char* output, size_t output
 // Deserialize a module from binary form.
 BinaryenModuleRef BinaryenModuleRead(char* input, size_t inputSize);
 
+// Execute a module in the Binaryen interpreter. This will create an instance of
+// the module, run it in the interpreter - which means running the start method -
+// and then destroying the instance.
+void BinaryenModuleInterpret(BinaryenModuleRef module);
+
 //
 // ========== CFG / Relooper ==========
 //
diff --git a/test/example/c-api-kitchen-sink.c b/test/example/c-api-kitchen-sink.c
index 84f04b45a..feffc9d4c 100644
--- a/test/example/c-api-kitchen-sink.c
+++ b/test/example/c-api-kitchen-sink.c
@@ -433,8 +433,29 @@ void test_binaries() {
   BinaryenModuleDispose(module);
 }
 
+void test_interpret() {
+  // create a simple module with a start method that prints a number, and interpret it, printing that number.
+  BinaryenModuleRef module = BinaryenModuleCreate();
+
+  BinaryenType iparams[2] = { BinaryenInt32() };
+  BinaryenFunctionTypeRef vi = BinaryenAddFunctionType(module, "vi", BinaryenNone(), iparams, 1);
+  BinaryenAddImport(module, "print-i32", "spectest", "print", vi);
+
+  BinaryenFunctionTypeRef v = BinaryenAddFunctionType(module, "v", BinaryenNone(), NULL, 0);
+  BinaryenExpressionRef callOperands[] = { makeInt32(module, 1234) };
+  BinaryenExpressionRef call = BinaryenCallImport(module, "print-i32", callOperands, 1, BinaryenNone());
+  BinaryenFunctionRef starter = BinaryenAddFunction(module, "starter", v, NULL, 0, call);
+  BinaryenSetStart(module, starter);
+
+  BinaryenModulePrint(module);
+  assert(BinaryenModuleValidate(module));
+  BinaryenModuleInterpret(module);
+  BinaryenModuleDispose(module);
+}
+
 int main() {
   test_core();
   test_relooper();
   test_binaries();
+  test_interpret();
 }
diff --git a/test/example/c-api-kitchen-sink.txt b/test/example/c-api-kitchen-sink.txt
index e4973ba16..6776fe2a5 100644
--- a/test/example/c-api-kitchen-sink.txt
+++ b/test/example/c-api-kitchen-sink.txt
@@ -664,3 +664,16 @@ module loaded from binary form:
     )
   )
 )
+(module
+  (memory 0)
+  (start $starter)
+  (type $vi (func (param i32)))
+  (type $v (func))
+  (import $print-i32 "spectest" "print" (param i32))
+  (func $starter (type $v)
+    (call_import $print-i32
+      (i32.const 1234)
+    )
+  )
+)
+(i32.const 1234)