Support using JSPI to load the secondary wasm split module. (#5431)

When using JSPI with wasm-split, any calls to secondary module functions
will now first check a global to see  if the module is loaded. If not
loaded it will call a JSPI'ed function that will handle loading module.

The setup is split into the JSPI pass and wasm-split tool since the JSPI
pass is first run by emscripten and we need to JSPI'ify the load secondary
module function. wasm-split then injects all the checks and calls to the
load function.

1 files changed, 5 insertions, 0 deletions

diff --git a/src/ir/module-splitting.h b/src/ir/module-splitting.h
index 2cc6760c0..dc5bb1998 100644
--- a/src/ir/module-splitting.h
+++ b/src/ir/module-splitting.h
@@ -44,6 +44,8 @@
 
 namespace wasm::ModuleSplitting {
 
+static const Name LOAD_SECONDARY_MODULE("__load_secondary_module");
+
 struct Config {
   // The set of functions to keep in the primary module. All others are split
   // out into the new secondary module. Must include the start function if it
@@ -64,6 +66,9 @@ struct Config {
   // false, the original function names will be used (after `newExportPrefix`)
   // as the new export names.
   bool minimizeNewExportNames = false;
+  // When JSPI support is enabled the secondary module loading is handled by an
+  // imported function.
+  bool jspi = false;
 };
 
 struct Results {