mirror of
https://github.com/carbon-language/carbon-lang.git
synced 2026-09-24 20:30:14 +01:00
82 lines
2.8 KiB
C++
82 lines
2.8 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/merge.h"
|
|
|
|
#include "toolchain/check/function.h"
|
|
#include "toolchain/check/import_ref.h"
|
|
|
|
namespace Carbon::Check {
|
|
|
|
// Returns the instruction to consider when merging the given inst_id. Returns
|
|
// nullopt if merging is infeasible and no diagnostic should be printed.
|
|
static auto ResolveMergeableInst(Context& context, SemIR::InstId inst_id)
|
|
-> std::optional<SemIR::Inst> {
|
|
auto inst = context.insts().Get(inst_id);
|
|
switch (inst.kind()) {
|
|
case SemIR::ImportRefUnused::Kind:
|
|
// Resolve before merging.
|
|
TryResolveImportRefUnused(context, inst_id);
|
|
break;
|
|
|
|
case SemIR::ImportRefUsed::Kind:
|
|
// Already resolved.
|
|
break;
|
|
|
|
case SemIR::Namespace::Kind:
|
|
// Return back the namespace directly.
|
|
return inst;
|
|
|
|
default:
|
|
CARBON_FATAL() << "Unexpected inst kind passed to ResolveMergeableInst: "
|
|
<< inst;
|
|
}
|
|
|
|
auto const_id = context.constant_values().Get(inst_id);
|
|
// TODO: Function and type declarations are constant, but `var` declarations
|
|
// are non-constant and should still merge.
|
|
if (!const_id.is_constant()) {
|
|
return std::nullopt;
|
|
}
|
|
return context.insts().Get(const_id.inst_id());
|
|
}
|
|
|
|
auto MergeImportRef(Context& context, SemIR::InstId new_inst_id,
|
|
SemIR::InstId prev_inst_id) -> void {
|
|
auto new_inst = ResolveMergeableInst(context, new_inst_id);
|
|
auto prev_inst = ResolveMergeableInst(context, prev_inst_id);
|
|
if (!new_inst || !prev_inst) {
|
|
// TODO: Once `var` declarations get an associated instruction for handling,
|
|
// it might be more appropriate to return without diagnosing here, to handle
|
|
// invalid declarations.
|
|
context.DiagnoseDuplicateName(new_inst_id, prev_inst_id);
|
|
return;
|
|
}
|
|
|
|
if (new_inst->kind() != prev_inst->kind()) {
|
|
context.DiagnoseDuplicateName(new_inst_id, prev_inst_id);
|
|
return;
|
|
}
|
|
|
|
switch (new_inst->kind()) {
|
|
case SemIR::FunctionDecl::Kind: {
|
|
auto new_fn = context.functions().Get(
|
|
new_inst->As<SemIR::FunctionDecl>().function_id);
|
|
auto prev_fn_id = prev_inst->As<SemIR::FunctionDecl>().function_id;
|
|
// TODO: May need to "spoil" the new function to prevent it from being
|
|
// emitted, since it will already be added.
|
|
MergeFunctionRedecl(context, context.insts().GetLocId(new_inst_id),
|
|
new_fn,
|
|
/*new_is_definition=*/false, prev_fn_id,
|
|
/*prev_is_imported=*/true);
|
|
return;
|
|
}
|
|
default:
|
|
context.TODO(new_inst_id, "Merging not yet supported.");
|
|
return;
|
|
}
|
|
}
|
|
|
|
} // namespace Carbon::Check
|