YJIT: Fix exits on splatkw instruction (#9711)

bootstraptest/test_yjit.rb

@@ -2521,6 +2521,18 @@ assert_equal '[1, 2, 3, 4, 5]', %q{
   splatarray
 }
 
+# splatkw
+assert_equal '[1, 2]', %q{
+  def foo(a:) = [a, yield]
+
+  def entry(&block)
+    a = { a: 1 }
+    foo(**a, &block)
+  end
+
+  entry { 2 }
+}
+
 assert_equal '[1, 1, 2, 1, 2, 3]', %q{
   def expandarray
     arr = [1, 2, 3]

yjit/bindgen/src/main.rs

@@ -119,6 +119,7 @@ fn main() {
         .allowlist_function("rb_hash_new_with_size")
         .allowlist_function("rb_hash_resurrect")
         .allowlist_function("rb_hash_stlike_foreach")
+        .allowlist_function("rb_to_hash_type")
 
         // From include/ruby/st.h
         .allowlist_type("st_retval")

yjit/src/codegen.rs

@@ -1435,6 +1435,33 @@ fn gen_splatarray(
     Some(KeepCompiling)
 }
 
+// call to_hash on hash to keyword splat before converting block
+// e.g. foo(**object, &block)
+fn gen_splatkw(
+    jit: &mut JITState,
+    asm: &mut Assembler,
+    _ocb: &mut OutlinedCb,
+) -> Option<CodegenStatus> {
+    // Save the PC and SP because the callee may allocate
+    jit_prepare_routine_call(jit, asm);
+
+    // Get the operands from the stack
+    let block_opnd = asm.stack_opnd(0);
+    let block_type = asm.ctx.get_opnd_type(block_opnd.into());
+    let hash_opnd = asm.stack_opnd(1);
+
+    let hash = asm.ccall(rb_to_hash_type as *const u8, vec![hash_opnd]);
+    asm.stack_pop(2); // Keep it on stack during ccall for GC
+
+    let stack_ret = asm.stack_push(Type::Hash);
+    asm.mov(stack_ret, hash);
+    asm.stack_push(block_type);
+    // Leave block_opnd spilled by ccall as is
+    asm.ctx.dealloc_temp_reg(asm.ctx.get_stack_size() - 1);
+
+    Some(KeepCompiling)
+}
+
 // concat two arrays
 fn gen_concatarray(
     jit: &mut JITState,
@@ -8951,6 +8978,7 @@ fn get_gen_fn(opcode: VALUE) -> Option<InsnGenFn> {
         YARVINSN_opt_str_uminus => Some(gen_opt_str_uminus),
         YARVINSN_opt_newarray_send => Some(gen_opt_newarray_send),
         YARVINSN_splatarray => Some(gen_splatarray),
+        YARVINSN_splatkw => Some(gen_splatkw),
         YARVINSN_concatarray => Some(gen_concatarray),
         YARVINSN_concattoarray => Some(gen_concattoarray),
         YARVINSN_pushtoarray => Some(gen_pushtoarray),

yjit/src/cruby_bindings.inc.rs

@@ -1015,6 +1015,7 @@ extern "C" {
     pub fn rb_obj_as_string_result(str_: VALUE, obj: VALUE) -> VALUE;
     pub fn rb_str_concat_literals(num: usize, strary: *const VALUE) -> VALUE;
     pub fn rb_ec_str_resurrect(ec: *mut rb_execution_context_struct, str_: VALUE) -> VALUE;
+    pub fn rb_to_hash_type(obj: VALUE) -> VALUE;
     pub fn rb_hash_stlike_foreach(
         hash: VALUE,
         func: st_foreach_callback_func,