merge revision(s) c178926fbe879045fa711444a1fd9e906af23e3b,a4b7ec12298c78392797e5ba7704076550e4f100: [Backport #19444]

YJIT: jit_prepare_routine_call() for String#+@ missing

	We saw SEGVs due to this when running with StackProf, which needs a
	correct PC for RUBY_INTERNAL_EVENT_NEWOBJ, the same event used for
	ObjectSpace allocation tracing.

	[Bug #19444]
	---
	 test/ruby/test_yjit.rb | 27 +++++++++++++++++++++++++++
	 yjit/src/codegen.rs    |  5 ++++-
	 2 files changed, 31 insertions(+), 1 deletion(-)

	YJIT: Fix false assumption that String#+@ => ::String

	Could return a subclass.

	[Bug #19444]
	---
	 test/ruby/test_yjit.rb | 17 +++++++++++++++++
	 yjit/src/codegen.rs    | 10 +++++++---
	 2 files changed, 24 insertions(+), 3 deletions(-)

test/ruby/test_yjit.rb

@@ -1077,6 +1077,50 @@ class TestYJIT < Test::Unit::TestCase
     RUBY
   end
 
+  def test_tracing_str_uplus
+    assert_compiles(<<~RUBY, frozen_string_literal: true, result: :ok)
+      def str_uplus
+        _ = 1
+        _ = 2
+        ret = [+"frfr", __LINE__]
+        _ = 3
+        _ = 4
+
+        ret
+      end
+
+      str_uplus
+      require 'objspace'
+      ObjectSpace.trace_object_allocations_start
+
+      str, expected_line = str_uplus
+      alloc_line = ObjectSpace.allocation_sourceline(str)
+
+      if expected_line == alloc_line
+        :ok
+      else
+        [expected_line, alloc_line]
+      end
+    RUBY
+  end
+
+  def test_str_uplus_subclass
+    assert_compiles(<<~RUBY, frozen_string_literal: true, result: :subclass)
+      class S < String
+        def encoding
+          :subclass
+        end
+      end
+
+      def test(str)
+        (+str).encoding
+      end
+
+      test ""
+      test S.new
+    RUBY
+  end
+
   private
 
   def code_gc_helpers

version.h

@@ -11,7 +11,7 @@
 # define RUBY_VERSION_MINOR RUBY_API_VERSION_MINOR
 #define RUBY_VERSION_TEENY 1
 #define RUBY_RELEASE_DATE RUBY_RELEASE_YEAR_STR"-"RUBY_RELEASE_MONTH_STR"-"RUBY_RELEASE_DAY_STR
-#define RUBY_PATCHLEVEL 35
+#define RUBY_PATCHLEVEL 36
 
 #include "ruby/version.h"
 #include "ruby/internal/abi.h"

yjit/src/codegen.rs

@@ -4047,17 +4047,24 @@ fn jit_rb_int_equal(
 
 /// If string is frozen, duplicate it to get a non-frozen string. Otherwise, return it.
 fn jit_rb_str_uplus(
-    _jit: &mut JITState,
+    jit: &mut JITState,
     ctx: &mut Context,
     asm: &mut Assembler,
     _ocb: &mut OutlinedCb,
     _ci: *const rb_callinfo,
     _cme: *const rb_callable_method_entry_t,
     _block: Option<IseqPtr>,
-    _argc: i32,
+    argc: i32,
     _known_recv_class: *const VALUE,
 ) -> bool
 {
+    if argc != 0 {
+        return false;
+    }
+
+    // We allocate when we dup the string
+    jit_prepare_routine_call(jit, ctx, asm);
+
     asm.comment("Unary plus on string");
     let recv_opnd = asm.load(ctx.stack_pop(1));
     let flags_opnd = asm.load(Opnd::mem(64, recv_opnd, RUBY_OFFSET_RBASIC_FLAGS));
@@ -4065,8 +4072,8 @@ fn jit_rb_str_uplus(
 
     let ret_label = asm.new_label("stack_ret");
 
-    // We guard for the receiver being a ::String, so the return value is too
-    let stack_ret = ctx.stack_push(Type::CString);
+    // String#+@ can only exist on T_STRING
+    let stack_ret = ctx.stack_push(Type::TString);
 
     // If the string isn't frozen, we just return it.
     asm.mov(stack_ret, recv_opnd);