YJIT: Move runtime type check into YJIT.

Performing the check in YJIT means we can make assumptions about the type. It also improves correctness of stack traces in cases where the codepoint argument is not a String or a Fixnum.
ruby · Aug 2, 2024 · 44af5ee · 44af5ee
1 parent 003ca52
commit 44af5ee
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Showing 3 changed files with 44 additions and 1 deletion.
diff --git a/string.c b/string.c
@@ -12300,7 12300,7 @@ rb_enc_interned_str_cstr(const char *ptr, rb_encoding *enc)
 void
 rb_yjit_str_concat_codepoint(VALUE str, VALUE codepoint)
 {
- if (RB_LIKELY(FIXNUM_P(codepoint)) && RB_LIKELY(ENCODING_GET_INLINED(str) == rb_ascii8bit_encindex())) {
  if (RB_LIKELY(ENCODING_GET_INLINED(str) == rb_ascii8bit_encindex())) {
  ssize_t code = RB_NUM2SSIZE(codepoint);
 
  if (RB_LIKELY(code >= 0 && code < 0xff)) {

diff --git a/yjit/src/codegen.rs b/yjit/src/codegen.rs
@@ -1999,6 1999,46 @@ fn guard_object_is_hash(
  }
 }
 
 fn guard_object_is_fixnum(
  jit: &mut JITState,
  asm: &mut Assembler,
  object: Opnd,
  object_opnd: YARVOpnd
 ) {
  let object_type = asm.ctx.get_opnd_type(object_opnd);
  if object_type.is_heap() {
  asm_comment!(asm, "arg is heap object");
  asm.jmp(Target::side_exit(Counter::guard_send_not_fixnum));
  return;
  }
 
  if object_type != Type::Fixnum && object_type.is_specific() {
  asm_comment!(asm, "arg is not fixnum");
  asm.jmp(Target::side_exit(Counter::guard_send_not_fixnum));
  return;
  }
 
  assert!(!object_type.is_heap());
  assert!(object_type == Type::Fixnum || object_type.is_unknown());
 
  // If not fixnums at run-time, fall back
  if object_type != Type::Fixnum {
  asm_comment!(asm, "guard object fixnum");
  asm.test(object, Opnd::UImm(RUBY_FIXNUM_FLAG as u64));
 
  jit_chain_guard(
  JCC_JZ,
  jit,
  asm,
  SEND_MAX_DEPTH,
  Counter::guard_send_not_fixnum,
  );
  }
 
  // Set the stack type in the context.
  asm.ctx.upgrade_opnd_type(object.into(), Type::Fixnum);
 }
 
 fn guard_object_is_string(
  asm: &mut Assembler,
  object: Opnd,
@@ -5791,6 5831,8 @@ fn jit_rb_str_concat_codepoint(
  let codepoint = asm.stack_opnd(0);
  let recv = asm.stack_opnd(1);
 
  guard_object_is_fixnum(jit, asm, codepoint, StackOpnd(0));
 
  asm.ccall(rb_yjit_str_concat_codepoint as *const u8, vec![recv, codepoint]);
 
  // The receiver is the return value, so we only need to pop the codepoint argument off the stack.

diff --git a/yjit/src/stats.rs b/yjit/src/stats.rs
@@ -453,6 453,7 @@ make_counters! {
  guard_send_instance_of_class_mismatch,
  guard_send_interrupted,
  guard_send_not_fixnums,
  guard_send_not_fixnum,
  guard_send_not_fixnum_or_flonum,
  guard_send_not_string,
  guard_send_respond_to_mid_mismatch,