wasm-emscripten-finalize: Do not skip the start function body (#3714)

When we can skip function bodies, we still need to parse the start function
for the pthreads case, see details in the comments. This still gives us 99%
of the speedup as the start function is just 1 function and it's not that big,
so with this we return to full speed after the reversion in #3705

1 files changed, 13 insertions, 0 deletions

diff --git a/test/lld/em_asm_pthread.cpp b/test/lld/em_asm_pthread.cpp
new file mode 100644
index 000000000..d327bedf2
--- /dev/null
+++ b/test/lld/em_asm_pthread.cpp
@@ -0,0 +1,13 @@
+// Build with
+//
+// emcc a.cpp -pthread -s WASM_BIGINT
+//
+
+#include <emscripten.h>
+
+EM_JS(void, world, (), { console.log("World."); });
+
+int main() {
+  EM_ASM({ console.log("Hello."); });
+  world();
+}