[mono][wasm] Add a 'wasm-gc-safepoints' option to enable the generation of GC...

[mono][wasm] Add a 'wasm-gc-safepoints' option to enable the generation of GC safe points in AOTed code on WASM. (#70520)

src/mono/mono/mini/mini-llvm.c

@@ -11831,7 +11831,7 @@ emit_method_inner (EmitContext *ctx)
 	}
 	ctx->has_safepoints = requires_safepoint;
 
-	if (!cfg->llvm_only && mono_threads_are_safepoints_enabled () && requires_safepoint) {
+	if (requires_safepoint && mini_safepoints_enabled ()) {
 		if (!cfg->compile_aot) {
 			LLVMSetGC (method, "coreclr");
 			emit_gc_safepoint_poll (ctx->module, ctx->lmodule, cfg);

src/mono/mono/mini/mini.h

@@ -41,6 +41,7 @@
 #include <mono/utils/mono-conc-hashtable.h>
 #include <mono/utils/mono-signal-handler.h>
 #include <mono/utils/ftnptr.h>
+#include <mono/utils/options.h>
 #include <mono/metadata/icalls.h>
 
 // Forward declare so that mini-*.h can have pointers to them.
@@ -2931,7 +2932,7 @@ static inline gboolean
 mini_safepoints_enabled (void)
 {
 #if defined (TARGET_WASM)
-	return FALSE;
+	return mono_opt_wasm_gc_safepoints;
 #else
 	return TRUE;
 #endif

src/mono/mono/utils/options-def.h

@@ -57,7 +57,8 @@ DEFINE_BOOL_READONLY(readonly_flag, "readonly-flag", FALSE, "Example")
 #endif
 */
 
-DEFINE_BOOL(wasm_exceptions, "wasm-exceptions", FALSE, "Enable codegen for wasm exceptions")
+DEFINE_BOOL(wasm_exceptions, "wasm-exceptions", FALSE, "Enable codegen for WASM exceptions")
+DEFINE_BOOL(wasm_gc_safepoints, "wasm-gc-safepoints", FALSE, "Use GC safepoints on WASM")
 DEFINE_BOOL(aot_lazy_assembly_load, "aot-lazy-assembly-load", FALSE, "Load assemblies referenced by AOT images lazily")
 
 /* Cleanup */

src/mono/wasm/build/WasmApp.Native.targets

@@ -531,6 +531,7 @@
       <MonoAOTCompilerDefaultAotArguments Include="deterministic" />
       <MonoAOTCompilerDefaultAotArguments Include="mattr=simd" Condition="'$(WasmSIMD)' == 'true'" />
       <MonoAOTCompilerDefaultProcessArguments Include="--wasm-exceptions" Condition="'$(WasmExceptionHandling)' == 'true'" />
+      <MonoAOTCompilerDefaultProcessArguments Include="--wasm-gc-safepoints" Condition="'$(WasmEnableThreads)' == 'true' or '$(WasmEnablePerfTracing)' == 'true'" />
       <AotProfilePath Include="$(WasmAotProfilePath)"/>
     </ItemGroup>
     <ItemGroup>