return res
end
+ # Calls handling
+
+ # Compile a call within a callsite
+ fun compile_callsite(callsite: CallSite, arguments: Array[RuntimeVariable]): nullable RuntimeVariable do
+ var initializers = callsite.mpropdef.initializers
+ if not initializers.is_empty then
+ var recv = arguments.first
+
+ var i = 1
+ for p in initializers do
+ if p isa MMethod then
+ var args = [recv]
+ var msignature = p.intro.msignature
+ if msignature != null then
+ for x in msignature.mparameters do
+ args.add arguments[i]
+ i += 1
+ end
+ end
+ send(p, args)
+ else if p isa MAttribute then
+ info("NOT YET IMPLEMENTED {class_name}::compile_callsite for MAttribute `{p}`")
+ #self.write_attribute(p, recv, arguments[i])
+ i += 1
+ else abort
+ end
+ assert i == arguments.length
+
+ return send(callsite.mproperty, [recv])
+ end
+
+ return send(callsite.mproperty, arguments)
+ end
+
+ # Evaluate `args` as expressions in the call of `mpropdef` on `recv`.
+ #
+ # This method is used to manage varargs in signatures and returns the real array
+ # of runtime variables to use in the call.
+ fun varargize(mpropdef: MMethodDef, map: nullable SignatureMap, recv: RuntimeVariable, args: SequenceRead[AExpr]): Array[RuntimeVariable] do
+ var msignature = mpropdef.new_msignature or else mpropdef.msignature.as(not null)
+ var res = new Array[RuntimeVariable]
+ res.add(recv)
+
+ if msignature.arity == 0 then return res
+
+ if map == null then
+ assert args.length == msignature.arity
+ for ne in args do
+ res.add expr(ne, null)
+ end
+ return res
+ end
+
+ # Eval in order of arguments, not parameters
+ var exprs = new Array[RuntimeVariable].with_capacity(args.length)
+ for ne in args do
+ exprs.add expr(ne, null)
+ end
+
+ # Fill `res` with the result of the evaluation according to the mapping
+ for i in [0..msignature.arity[ do
+ var param = msignature.mparameters[i]
+ var j = map.map.get_or_null(i)
+ if j == null then
+ # default value
+ res.add(null_instance)
+ continue
+ end
+ if param.is_vararg and map.vararg_decl > 0 then
+ var vararg = exprs.sub(j, map.vararg_decl)
+ var elttype = param.mtype
+ var arg = self.vararg_instance(mpropdef, recv, vararg, elttype)
+ res.add(arg)
+ continue
+ end
+ res.add exprs[j]
+ end
+ return res
+ end
+
+ # Generate a static call on a method definition (no receiver needed).
+ fun static_call(mmethoddef: MMethodDef, arguments: Array[RuntimeVariable]): nullable RuntimeVariable do
+ var res: nullable RuntimeVariable
+ var ret = mmethoddef.msignature.as(not null).return_mtype
+ if ret == null then
+ res = null
+ else
+ ret = ret.resolve_for(mmethoddef.mclassdef.bound_mtype, mmethoddef.mclassdef.bound_mtype, mmethoddef.mclassdef.mmodule, true)
+ res = self.new_var(ret)
+ end
+
+ # Autobox arguments
+ adapt_signature(mmethoddef, arguments)
+
+ var rt_name = mmethoddef.rt_name
+ if res == null then
+ add("{rt_name}.get{rt_name}().exec(new RTVal[]\{{arguments.join(",")}\});")
+ return null
+ end
+ var ress = new_expr("{rt_name}.get{rt_name}().exec(new RTVal[]\{{arguments.join(",")}\});", compiler.mainmodule.object_type)
+ assign(res, ress)
+ return res
+ end
+
+ # Generate a polymorphic send for `method` with `arguments`
+ fun send(mmethod: MMethod, arguments: Array[RuntimeVariable]): nullable RuntimeVariable do
+ # Polymorphic send
+ return table_send(mmethod, arguments)
+ end
+
+
+ # Handle common special cases before doing the effective method invocation
+ # This methods handle the `==` and `!=` methods and the case of the null receiver.
+ # Note: a { is open in the generated C, that enclose and protect the effective method invocation.
+ # Client must not forget to close the } after them.
+ #
+ # The value returned is the result of the common special cases.
+ # If not null, client must compile it with the result of their own effective method invocation.
+ #
+ # If `before_send` can shortcut the whole message sending, a dummy `if(0){`
+ # is generated to cancel the effective method invocation that will follow
+ # TODO: find a better approach
+ private fun before_send(res: nullable RuntimeVariable, mmethod: MMethodDef, arguments: Array[RuntimeVariable]) do
+ var bool_type = compiler.mainmodule.bool_type
+ var recv = arguments.first
+ var consider_null = mmethod.name == "==" or mmethod.name == "!=" or mmethod.name == "is_same_instance"
+ if recv.mcasttype isa MNullableType or recv.mcasttype isa MNullType then
+ add("if ({recv} == null || {recv}.is_null()) \{")
+ if mmethod.name == "==" or mmethod.name == "is_same_instance" then
+ if res == null then res = new_var(bool_type)
+ var arg = arguments[1]
+ if arg.mcasttype isa MNullableType then
+ add("{res} = ({arg} == null || {arg}.is_null());")
+ else if arg.mcasttype isa MNullType then
+ add("{res} = true; /* is null */")
+ else
+ add("{res} = false; /* {arg.inspect} cannot be null */")
+ end
+ else if mmethod.name == "!=" then
+ if res == null then res = new_var(bool_type)
+ # res = self.new_var(bool_type)
+ var arg = arguments[1]
+ if arg.mcasttype isa MNullableType then
+ add("{res} = ({arg} != null && !{arg}.is_null());")
+ else if arg.mcasttype isa MNullType then
+ add("{res} = false; /* is null */")
+ else
+ add("{res} = true; /* {arg.inspect} cannot be null */")
+ end
+ else
+ add_abort("Receiver is null")
+ ret(null_instance)
+ end
+ add("\} else \{")
+ else
+ add "\{"
+ add "/* recv ({recv}) cannot be null since it's a {recv.mcasttype}"
+ end
+ if consider_null then
+ var arg = arguments[1]
+ if arg.mcasttype isa MNullType then
+ if res == null then res = new_var(bool_type)
+ if mmethod.name == "!=" then
+ add("{res} = true; /* arg is null and recv is not */")
+ else # `==` and `is_same_instance`
+ add("{res} = false; /* arg is null but recv is not */")
+ end
+ add("\}") # closes the null case
+ add("if (false) \{") # what follow is useless, Javac will drop it
+ end
+ end
+ end
+
+ # Perform a method call through vft
+ private fun table_send(mmethod: TableCallable, arguments: Array[RuntimeVariable]): nullable RuntimeVariable do
+ var mdef: MMethodDef
+ var name: String
+ if mmethod isa MMethod then
+ mdef = mmethod.intro
+ name = mmethod.full_name
+ else if mmethod isa MMethodDef then
+ mdef = mmethod
+ name = mmethod.full_name
+ else
+ abort
+ end
+
+ var recv = arguments.first
+ var rect = mdef.mclassdef.bound_mtype
+ var msignature = mdef.msignature.as(not null)
+ msignature = msignature.resolve_for(rect, rect, compiler.mainmodule, true)
+ adapt_signature(mdef, arguments)
+
+ var res: nullable RuntimeVariable
+ var ret = msignature.return_mtype
+ if ret == null then
+ res = null
+ else
+ res = self.new_var(ret)
+ end
+
+ before_send(res, mdef, arguments)
+
+ add "/* concrete call to {mdef} */"
+ if res != null then
+ var ress = new_expr("{recv}.rtclass.vft.get(\"{name}\").exec(new RTVal[]\{{arguments.join(",")}\});", compiler.mainmodule.object_type)
+ assign(res, ress)
+ else
+ add("{recv}.rtclass.vft.get(\"{name}\").exec(new RTVal[]\{{arguments.join(",")}\});")
+ end
+
+ add("\}") # closes the null case
+
+ return res
+ end
+
# Code generation
# Add a line (will be suffixed by `\n`)
return new RuntimeVariable("null", t, t)
end
+ # Get an instance of a array for a vararg
+ fun vararg_instance(mpropdef: MPropDef, recv: RuntimeVariable, varargs: Array[RuntimeVariable], elttype: MType): RuntimeVariable do
+ # TODO handle dynamic types
+ info("NOT YET IMPLEMENTED vararg_instance")
+ return null_instance
+ # TODO return array_instance(varargs, elttype)
+ end
+
# Utils
# Display a info message
end
end
+# Used as a common type between MMethod and MMethodDef for `table_send`
+private interface TableCallable
+end
+
+redef class MMethod
+ super TableCallable
+end
+
redef class MMethodDef
+ super TableCallable
# Runtime name
private fun rt_name: String do
end
end
+redef class ASendExpr
+ redef fun expr(v) do
+ var recv = v.expr(n_expr, null)
+ var callsite = callsite.as(not null)
+ var args = v.varargize(callsite.mpropdef, callsite.signaturemap, recv, raw_arguments)
+ return v.compile_callsite(callsite, args)
+ end
+end
+
redef class ASelfExpr
redef fun expr(v) do return v.frame.as(not null).arguments.first
end
nitlanguage / nit.git / commitdiff