llvm-mirror/lib/MC/SubtargetFeature.cpp
Craig Topper 14fa6aa690 [Subtarget] Move SubtargetFeatureKV/SubtargetInfoKV from SubtargetFeature.h to MCSubtargetInfo.h. Move all code that operates on ProcFeatures and ProcDesc arrays to MCSubtargetInfo.
The SubtargetFeature class managed a list of features as strings. And it also had functions for setting bits in a FeatureBitset.

The methods that operated on the Feature list as strings are used in other parts of the backend. But the parts that operate on FeatureBitset are very tightly coupled to MCSubtargetInfo and requires passing in the arrays that MCSubtargetInfo owns. And the same struct type is used for ProcFeatures and ProcDesc.

This has led to MCSubtargetInfo having 2 arrays keyed by CPU name. One containing a mapping from a CPU name to its features. And one containing a mapping from CPU name to its scheduler model.

I would like to make a single CPU array containing all CPU information and remove some unneeded fields the ProcDesc array currently has. But I don't want to make SubtargetFeatures.h have to know about the scheduler model type and have to forward declare or pull in the header file.

Differential Revision: https://reviews.llvm.org/D58937

llvm-svn: 355428
2019-03-05 18:54:30 +00:00

83 lines
2.6 KiB
C++

//===- SubtargetFeature.cpp - CPU characteristics Implementation ----------===//
//
// 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
//
//===----------------------------------------------------------------------===//
//
/// \file Implements the SubtargetFeature interface.
//
//===----------------------------------------------------------------------===//
#include "llvm/MC/SubtargetFeature.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/ADT/Triple.h"
#include "llvm/Config/llvm-config.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
#include <algorithm>
#include <cassert>
#include <cstddef>
#include <cstring>
#include <iterator>
#include <string>
#include <vector>
using namespace llvm;
/// Splits a string of comma separated items in to a vector of strings.
void SubtargetFeatures::Split(std::vector<std::string> &V, StringRef S) {
SmallVector<StringRef, 3> Tmp;
S.split(Tmp, ',', -1, false /* KeepEmpty */);
V.assign(Tmp.begin(), Tmp.end());
}
void SubtargetFeatures::AddFeature(StringRef String, bool Enable) {
// Don't add empty features.
if (!String.empty())
// Convert to lowercase, prepend flag if we don't already have a flag.
Features.push_back(hasFlag(String) ? String.lower()
: (Enable ? "+" : "-") + String.lower());
}
SubtargetFeatures::SubtargetFeatures(StringRef Initial) {
// Break up string into separate features
Split(Features, Initial);
}
std::string SubtargetFeatures::getString() const {
return join(Features.begin(), Features.end(), ",");
}
void SubtargetFeatures::print(raw_ostream &OS) const {
for (auto &F : Features)
OS << F << " ";
OS << "\n";
}
#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
LLVM_DUMP_METHOD void SubtargetFeatures::dump() const {
print(dbgs());
}
#endif
void SubtargetFeatures::getDefaultSubtargetFeatures(const Triple& Triple) {
// FIXME: This is an inelegant way of specifying the features of a
// subtarget. It would be better if we could encode this information
// into the IR. See <rdar://5972456>.
if (Triple.getVendor() == Triple::Apple) {
if (Triple.getArch() == Triple::ppc) {
// powerpc-apple-*
AddFeature("altivec");
} else if (Triple.getArch() == Triple::ppc64) {
// powerpc64-apple-*
AddFeature("64bit");
AddFeature("altivec");
}
}
}