Fixes for static library EmitC sample. (iree-org#7738)

Co-authored-by: Ben Vanik <[email protected]>

build_tools/cmake/iree_copts.cmake

@@ -125,6 +125,9 @@ iree_select_compiler_opts(IREE_DEFAULT_COPTS
     # but it's better to not get spurious failures during LTCG.
     # https://docs.microsoft.com/en-us/cpp/build/reference/bigobj-increase-number-of-sections-in-dot-obj-file
     "/bigobj"
+
+    # Use the modern C preprocessor to more closely match standards/clang/gcc behavior.
+    "/Zc:preprocessor"
 )
 
 # Compiler diagnostics.

iree/compiler/Dialect/VM/Target/C/CModuleTarget.cpp

@@ -138,15 +138,15 @@ static LogicalResult buildModuleDescriptors(IREE::VM::ModuleOp &moduleOp,
   auto printStringView = [](StringRef s) -> std::string {
     // We can't use iree_make_string_view because function calls are not allowed
     // for constant expressions in C.
+    // TODO(#7605): Switch to IREE_SVL. We can't use IREE_SVL today because it
+    // uses designated initializers, which cause issues when compiled as C++.
     return ("{\"" + s + "\", " + std::to_string(s.size()) + "}").str();
   };
 
   // exports
   SmallVector<IREE::VM::ExportOp, 4> exportOps(
       moduleOp.getOps<IREE::VM::ExportOp>());
   std::string exportName = moduleName + "_exports_";
-  output << "static const size_t " << exportName
-         << "count_ = " << exportOps.size() << ";\n";
   output << "static const iree_vm_native_export_descriptor_t " << exportName
          << "[] = {\n";
   if (exportOps.empty()) {
@@ -183,8 +183,6 @@ static LogicalResult buildModuleDescriptors(IREE::VM::ModuleOp &moduleOp,
   SmallVector<IREE::VM::ImportOp, 4> importOps(
       moduleOp.getOps<IREE::VM::ImportOp>());
   std::string importName = moduleName + "_imports_";
-  output << "static const size_t " << importName
-         << "count_ = " << importOps.size() << ";\n";
   output << "static const iree_vm_native_import_descriptor_t " << importName
          << "[] = {\n";
   if (importOps.empty()) {
@@ -205,8 +203,6 @@ static LogicalResult buildModuleDescriptors(IREE::VM::ModuleOp &moduleOp,
 
   // functions
   std::string functionName = moduleName + "_funcs_";
-  output << "static const size_t " << functionName
-         << "count_ = " << exportOps.size() << ";\n";
   output << "static const iree_vm_native_function_ptr_t " << functionName
          << "[] = {\n";
   if (exportOps.empty()) {
@@ -241,11 +237,11 @@ static LogicalResult buildModuleDescriptors(IREE::VM::ModuleOp &moduleOp,
   output << "static const iree_vm_native_module_descriptor_t " << descriptorName
          << " = {\n"
          << printStringView(moduleName) << ",\n"
-         << importName << "count_,\n"
+         << importOps.size() << ",\n"
          << importName << ",\n"
-         << exportName << "count_,\n"
+         << exportOps.size() << ",\n"
          << exportName << ",\n"
-         << functionName << "count_,\n"
+         << exportOps.size() << ",\n"
          << functionName << ",\n"
          << "0,\n"
          << "NULL,\n"

iree/vm/shims_emitc.h

@@ -297,6 +297,7 @@ EMITC_DEFINE_SHIMS((r, i, i), (r))
 EMITC_DEFINE_SHIMS((r, i, i, i), (r))
 EMITC_DEFINE_SHIMS((r, i, i, i), (v))
 EMITC_DEFINE_SHIMS((r, r, i, i, i, i), (v))
+EMITC_DEFINE_SHIMS((r, r, r, i, i, i), (v))
 EMITC_DEFINE_SHIMS((r, r), (r))
 EMITC_DEFINE_SHIMS((r, r), (v))
 EMITC_DEFINE_SHIMS((r, r, r), (i, i))
@@ -309,5 +310,6 @@ EMITC_VLA_IMPORT((r, i), (r), (r))
 EMITC_VLA_IMPORT((r, i, i), (i), (r))
 EMITC_VLA_IMPORT((r, r, i), (i, r, i, i), (v))
 EMITC_VLA_IMPORT((r, r, r), (r), (r))
+EMITC_VLA_IMPORT((r, r, i, i), (i), (v))
 
 #endif  // IREE_VM_SHIMS_EMITC_H_