RJIT: Remove Type::CArray and limit use of Type::CString

See previous similar YJIT commit.

lib/ruby_vm/rjit/insn_compiler.rb

@@ -794,7 +794,7 @@ def putstring(jit, ctx, asm)
       asm.mov(C_ARGS[1], to_value(put_val))
       asm.call(C.rb_ec_str_resurrect)
 
-      stack_top = ctx.stack_push(Type::CString)
+      stack_top = ctx.stack_push(Type::TString)
       asm.mov(stack_top, C_RET)
 
       KeepCompiling
@@ -817,7 +817,7 @@ def concatstrings(jit, ctx, asm)
       asm.call(C.rb_str_concat_literals)
 
       ctx.stack_pop(n)
-      stack_ret = ctx.stack_push(Type::CString)
+      stack_ret = ctx.stack_push(Type::TString)
       asm.mov(stack_ret, C_RET)
 
       KeepCompiling
@@ -932,7 +932,7 @@ def newarray(jit, ctx, asm)
       asm.call(C.rb_ec_ary_new_from_values)
 
       ctx.stack_pop(n)
-      stack_ret = ctx.stack_push(Type::CArray)
+      stack_ret = ctx.stack_push(Type::TArray)
       asm.mov(stack_ret, C_RET)
 
       KeepCompiling
@@ -954,7 +954,7 @@ def duparray(jit, ctx, asm)
       asm.mov(C_ARGS[0], ary)
       asm.call(C.rb_ary_resurrect)
 
-      stack_ret = ctx.stack_push(Type::CArray)
+      stack_ret = ctx.stack_push(Type::TArray)
       asm.mov(stack_ret, C_RET)
 
       KeepCompiling
@@ -3082,7 +3082,7 @@ def jit_rb_str_concat(jit, ctx, asm, argc, known_recv_class)
       asm.test(recv_reg, C::RUBY_ENCODING_MASK)
 
       # Push once, use the resulting operand in both branches below.
-      stack_ret = ctx.stack_push(Type::CString)
+      stack_ret = ctx.stack_push(Type::TString)
 
       enc_mismatch = asm.new_label('enc_mismatch')
       asm.jnz(enc_mismatch)
@@ -3779,9 +3779,14 @@ def jit_guard_known_klass(jit, ctx, asm, known_klass, obj_opnd, insn_opnd, compt
         jit_chain_guard(:jne, jit, ctx, asm, side_exit, limit:)
 
         if known_klass == C.rb_cString
-          ctx.upgrade_opnd_type(insn_opnd, Type::CString)
+          # Upgrading to Type::CString here is incorrect.
+          # The guard we put only checks RBASIC_CLASS(obj),
+          # which adding a singleton class can change. We
+          # additionally need to know the string is frozen
+          # to claim Type::CString.
+          ctx.upgrade_opnd_type(insn_opnd, Type::TString)
         elsif known_klass == C.rb_cArray
-          ctx.upgrade_opnd_type(insn_opnd, Type::CArray)
+          ctx.upgrade_opnd_type(insn_opnd, Type::TArray)
         end
       end
     end
@@ -4723,7 +4728,7 @@ def jit_call_iseq(jit, ctx, asm, cme, calling, iseq, frame_type: nil, prev_ep: n
           asm.call(C.rb_ec_ary_new_from_values)
 
           ctx.stack_pop(n)
-          stack_ret = ctx.stack_push(Type::CArray)
+          stack_ret = ctx.stack_push(Type::TArray)
           asm.mov(stack_ret, C_RET)
         end
       end

lib/ruby_vm/rjit/type.rb

@@ -35,7 +35,6 @@ def heap?
       case self
       in Type::UnknownHeap then true
       in Type::TArray then true
-      in Type::CArray then true
       in Type::Hash then true
       in Type::HeapSymbol then true
       in Type::TString then true
@@ -45,11 +44,10 @@ def heap?
       end
     end
 
-    # Check if it's a T_ARRAY object (both TArray and CArray are T_ARRAY)
+    # Check if it's a T_ARRAY object
     def array?
       case self
       in Type::TArray then true
-      in Type::CArray then true
       else false
       end
     end
@@ -73,7 +71,6 @@ def known_class
       in Type::Flonum then C.rb_cFloat
       in Type::ImmSymbol | Type::HeapSymbol then C.rb_cSymbol
       in Type::CString then C.rb_cString
-      in Type::CArray then C.rb_cArray
       else nil
       end
     end
@@ -115,11 +112,6 @@ def diff(dst)
         return TypeDiff::Compatible[1]
       end
 
-      # A CArray is also a TArray.
-      if self == Type::CArray && dst == Type::TArray
-        return TypeDiff::Compatible[1]
-      end
-
       # Specific heap type into unknown heap type is imperfect but valid
       if self.heap? && dst == Type::UnknownHeap
         return TypeDiff::Compatible[1]
@@ -169,12 +161,9 @@ def from(val)
         end
       else
         val_class = C.to_value(C.rb_class_of(val))
-        if val_class == C.rb_cString
+        if val_class == C.rb_cString && C.rb_obj_frozen_p(val)
           return Type::CString
         end
-        if val_class == C.rb_cArray
-          return Type::CArray
-        end
         if C.to_value(val) == C.rb_block_param_proxy
           return Type::BlockParamProxy
         end
@@ -222,7 +211,6 @@ def static_symbol?(obj)
   Type::TString = Type[:TString] # An object with the T_STRING flag set, possibly an rb_cString
   Type::CString = Type[:CString] # An un-subclassed string of type rb_cString (can have instance vars in some cases)
   Type::TArray  = Type[:TArray]  # An object with the T_ARRAY flag set, possibly an rb_cArray
-  Type::CArray  = Type[:CArray]  # An un-subclassed string of type rb_cArray (can have instance vars in some cases)
 
   Type::BlockParamProxy = Type[:BlockParamProxy] # A special sentinel value indicating the block parameter should be read from