Files
carbon-lang/toolchain/check/call.cpp
T
Jon Ross-Perkins bd2fa3ace7 Remove CalleeParamsInfo (#4452)
I'm seeing three issues with CalleeParamsInfo:

1. Although ResolveCalleeInCall had been extracted out and the
EntityWithParamsBase could be used directly, that had not been cleaned
up.
2. implicit_param_refs_id is unused; param_refs_id was only used by
ResolveCalleeInCall. The factoring as a struct seems to be obscuring
what's used and what isn't (creating unnecessary copies).
3. On #4446, CalleeParamsInfo seemed to be obfuscating what
ConvertCallArgs actually worked with (a Function, not a generic entity).

I'm thinking that just removing CalleeParamsInfo is the best resolution
here, it looks like it's tripping people up more than it's helping.

Note, I think Function used to be named Callable, which was where the
"callable" name originally came from (I might be wrong about this). But
"function" seems clearer about the type now.
2024-11-04 16:47:40 +00:00

223 lines
9.3 KiB
C++

// Part of the Carbon Language project, under the Apache License v2.0 with LLVM
// Exceptions. See /LICENSE for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
#include "toolchain/check/call.h"
#include "toolchain/base/kind_switch.h"
#include "toolchain/check/context.h"
#include "toolchain/check/convert.h"
#include "toolchain/check/deduce.h"
#include "toolchain/check/function.h"
#include "toolchain/diagnostics/format_providers.h"
#include "toolchain/sem_ir/builtin_function_kind.h"
#include "toolchain/sem_ir/builtin_inst_kind.h"
#include "toolchain/sem_ir/entity_with_params_base.h"
#include "toolchain/sem_ir/ids.h"
#include "toolchain/sem_ir/inst.h"
#include "toolchain/sem_ir/typed_insts.h"
namespace Carbon::Check {
namespace {
// Entity kinds, for diagnostics. Converted to an int for a select.
enum class EntityKind : uint8_t {
Function = 0,
GenericClass = 1,
GenericInterface = 2,
};
} // namespace
// Resolves the callee expression in a call to a specific callee, or diagnoses
// if no specific callee can be identified. This verifies the arity of the
// callee and determines any compile-time arguments, but doesn't check that the
// runtime arguments are convertible to the parameter types.
//
// `self_id` and `arg_ids` are the self argument and explicit arguments in the
// call.
//
// Returns a `SpecificId` for the specific callee, `SpecificId::Invalid` if the
// callee is not generic, or `nullopt` if an error has been diagnosed.
static auto ResolveCalleeInCall(Context& context, SemIR::LocId loc_id,
const SemIR::EntityWithParamsBase& entity,
EntityKind entity_kind_for_diagnostic,
SemIR::GenericId entity_generic_id,
SemIR::SpecificId enclosing_specific_id,
SemIR::InstId self_id,
llvm::ArrayRef<SemIR::InstId> arg_ids)
-> std::optional<SemIR::SpecificId> {
// Check that the arity matches.
auto params = context.inst_blocks().GetOrEmpty(entity.param_refs_id);
if (arg_ids.size() != params.size()) {
CARBON_DIAGNOSTIC(CallArgCountMismatch, Error,
"{0} argument{0:s} passed to "
"{1:=0:function|=1:generic class|=2:generic interface}"
" expecting {2} argument{2:s}",
IntAsSelect, IntAsSelect, IntAsSelect);
CARBON_DIAGNOSTIC(
InCallToEntity, Note,
"calling {0:=0:function|=1:generic class|=2:generic interface}"
" declared here",
IntAsSelect);
context.emitter()
.Build(loc_id, CallArgCountMismatch, arg_ids.size(),
static_cast<int>(entity_kind_for_diagnostic), params.size())
.Note(entity.latest_decl_id(), InCallToEntity,
static_cast<int>(entity_kind_for_diagnostic))
.Emit();
return std::nullopt;
}
// Perform argument deduction.
auto specific_id = SemIR::SpecificId::Invalid;
if (entity_generic_id.is_valid()) {
specific_id = DeduceGenericCallArguments(
context, loc_id, entity_generic_id, enclosing_specific_id,
entity.implicit_param_patterns_id, entity.param_patterns_id, self_id,
arg_ids);
if (!specific_id.is_valid()) {
return std::nullopt;
}
}
return specific_id;
}
// Performs a call where the callee is the name of a generic class, such as
// `Vector(i32)`.
static auto PerformCallToGenericClass(Context& context, SemIR::LocId loc_id,
SemIR::ClassId class_id,
SemIR::SpecificId enclosing_specific_id,
llvm::ArrayRef<SemIR::InstId> arg_ids)
-> SemIR::InstId {
const auto& generic_class = context.classes().Get(class_id);
auto callee_specific_id = ResolveCalleeInCall(
context, loc_id, generic_class, EntityKind::GenericClass,
generic_class.generic_id, enclosing_specific_id,
/*self_id=*/SemIR::InstId::Invalid, arg_ids);
if (!callee_specific_id) {
return SemIR::InstId::BuiltinError;
}
return context.AddInst<SemIR::ClassType>(
loc_id, {.type_id = SemIR::TypeId::TypeType,
.class_id = class_id,
.specific_id = *callee_specific_id});
}
// Performs a call where the callee is the name of a generic interface, such as
// `AddWith(i32)`.
static auto PerformCallToGenericInterface(
Context& context, SemIR::LocId loc_id, SemIR::InterfaceId interface_id,
SemIR::SpecificId enclosing_specific_id,
llvm::ArrayRef<SemIR::InstId> arg_ids) -> SemIR::InstId {
const auto& interface = context.interfaces().Get(interface_id);
auto callee_specific_id = ResolveCalleeInCall(
context, loc_id, interface, EntityKind::GenericInterface,
interface.generic_id, enclosing_specific_id,
/*self_id=*/SemIR::InstId::Invalid, arg_ids);
if (!callee_specific_id) {
return SemIR::InstId::BuiltinError;
}
return context.AddInst<SemIR::InterfaceType>(
loc_id, {.type_id = SemIR::TypeId::TypeType,
.interface_id = interface_id,
.specific_id = *callee_specific_id});
}
auto PerformCall(Context& context, SemIR::LocId loc_id, SemIR::InstId callee_id,
llvm::ArrayRef<SemIR::InstId> arg_ids) -> SemIR::InstId {
// Identify the function we're calling.
auto callee_function = GetCalleeFunction(context.sem_ir(), callee_id);
if (!callee_function.function_id.is_valid()) {
auto type_inst =
context.types().GetAsInst(context.insts().Get(callee_id).type_id());
CARBON_KIND_SWITCH(type_inst) {
case CARBON_KIND(SemIR::GenericClassType generic_class): {
return PerformCallToGenericClass(
context, loc_id, generic_class.class_id,
generic_class.enclosing_specific_id, arg_ids);
}
case CARBON_KIND(SemIR::GenericInterfaceType generic_interface): {
return PerformCallToGenericInterface(
context, loc_id, generic_interface.interface_id,
generic_interface.enclosing_specific_id, arg_ids);
}
default: {
if (!callee_function.is_error) {
CARBON_DIAGNOSTIC(CallToNonCallable, Error,
"value of type {0} is not callable", TypeOfInstId);
context.emitter().Emit(loc_id, CallToNonCallable, callee_id);
}
return SemIR::InstId::BuiltinError;
}
}
}
auto& function = context.functions().Get(callee_function.function_id);
// If the callee is a generic function, determine the generic argument values
// for the call.
auto callee_specific_id = ResolveCalleeInCall(
context, loc_id, function, EntityKind::Function, function.generic_id,
callee_function.enclosing_specific_id, callee_function.self_id, arg_ids);
if (!callee_specific_id) {
return SemIR::InstId::BuiltinError;
}
if (callee_specific_id->is_valid()) {
callee_id =
context.AddInst(context.insts().GetLocId(callee_id),
SemIR::SpecificFunction{
.type_id = context.GetBuiltinType(
SemIR::BuiltinInstKind::SpecificFunctionType),
.callee_id = callee_id,
.specific_id = *callee_specific_id});
context.definitions_required().push_back(callee_id);
}
// If there is a return slot, build storage for the result.
SemIR::InstId return_slot_arg_id = SemIR::InstId::Invalid;
SemIR::ReturnTypeInfo return_info = [&] {
DiagnosticAnnotationScope annotate_diagnostics(
&context.emitter(), [&](auto& builder) {
CARBON_DIAGNOSTIC(IncompleteReturnTypeHere, Note,
"return type declared here");
builder.Note(function.return_slot_id, IncompleteReturnTypeHere);
});
return CheckFunctionReturnType(context, callee_id, function,
*callee_specific_id);
}();
switch (return_info.init_repr.kind) {
case SemIR::InitRepr::InPlace:
// Tentatively put storage for a temporary in the function's return slot.
// This will be replaced if necessary when we perform initialization.
return_slot_arg_id = context.AddInst<SemIR::TemporaryStorage>(
loc_id, {.type_id = return_info.type_id});
break;
case SemIR::InitRepr::None:
// For functions with an implicit return type, the return type is the
// empty tuple type.
if (!return_info.type_id.is_valid()) {
return_info.type_id = context.GetTupleType({});
}
break;
case SemIR::InitRepr::ByCopy:
break;
case SemIR::InitRepr::Incomplete:
// Don't form an initializing expression with an incomplete type.
// CheckFunctionReturnType will have diagnosed this for us if needed.
return_info.type_id = SemIR::TypeId::Error;
break;
}
// Convert the arguments to match the parameters.
auto converted_args_id =
ConvertCallArgs(context, loc_id, callee_function.self_id, arg_ids,
return_slot_arg_id, function, *callee_specific_id);
auto call_inst_id =
context.AddInst<SemIR::Call>(loc_id, {.type_id = return_info.type_id,
.callee_id = callee_id,
.args_id = converted_args_id});
return call_inst_id;
}
} // namespace Carbon::Check