serge-sans-paille 5a7f47cc02
[clang] Optimize clang::Builtin::Info density
Reorganize clang::Builtin::Info to have them naturally align on 4 bytes
boundaries.

Instead of storing builtin headers as a straight char pointer, enumerate
them and store the enum. It allows to use a small enum instead of a
pointer to reference them.

On a 64 bit machine, this brings sizeof(clang::Builtin::Info) from 56
down to 48 bytes.

On a release build on my Linux 64 bit machine, it shrinks the size of
libclang-cpp.so by 193kB.

The impact on performance is negligible in terms of instruction count,
but the wall time seems better, see
https://llvm-compile-time-tracker.com/compare.php?from=b3d8639f3536a4876b511aca9fb7948ff9266cee&to=a89b56423f98b550260a58c41e64aff9e56b76be&stat=task-clock

Differential Revision: https://reviews.llvm.org/D142024
2023-01-23 14:27:44 +01:00

60 lines
2.0 KiB
C++

//===--- BPF.cpp - Implement BPF target feature support -------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file implements BPF TargetInfo objects.
//
//===----------------------------------------------------------------------===//
#include "BPF.h"
#include "Targets.h"
#include "clang/Basic/MacroBuilder.h"
#include "clang/Basic/TargetBuiltins.h"
#include "llvm/ADT/StringRef.h"
using namespace clang;
using namespace clang::targets;
static constexpr Builtin::Info BuiltinInfo[] = {
#define BUILTIN(ID, TYPE, ATTRS) \
{#ID, TYPE, ATTRS, nullptr, HeaderDesc::NO_HEADER, ALL_LANGUAGES},
#include "clang/Basic/BuiltinsBPF.def"
};
void BPFTargetInfo::getTargetDefines(const LangOptions &Opts,
MacroBuilder &Builder) const {
Builder.defineMacro("__bpf__");
Builder.defineMacro("__BPF__");
}
static constexpr llvm::StringLiteral ValidCPUNames[] = {"generic", "v1", "v2",
"v3", "probe"};
bool BPFTargetInfo::isValidCPUName(StringRef Name) const {
return llvm::is_contained(ValidCPUNames, Name);
}
void BPFTargetInfo::fillValidCPUList(SmallVectorImpl<StringRef> &Values) const {
Values.append(std::begin(ValidCPUNames), std::end(ValidCPUNames));
}
ArrayRef<Builtin::Info> BPFTargetInfo::getTargetBuiltins() const {
return llvm::ArrayRef(BuiltinInfo,
clang::BPF::LastTSBuiltin - Builtin::FirstTSBuiltin);
}
bool BPFTargetInfo::handleTargetFeatures(std::vector<std::string> &Features,
DiagnosticsEngine &Diags) {
for (const auto &Feature : Features) {
if (Feature == "+alu32") {
HasAlu32 = true;
}
}
return true;
}