xref: /llvm-project/llvm/lib/TargetParser/SubtargetFeature.cpp (revision 4d6d56315d4ea2ae2b8059b99e45bdfee764861a)
1 //===- SubtargetFeature.cpp - CPU characteristics Implementation ----------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 /// \file Implements the SubtargetFeature interface.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "llvm/TargetParser/SubtargetFeature.h"
14 #include "llvm/ADT/SmallVector.h"
15 #include "llvm/ADT/StringExtras.h"
16 #include "llvm/ADT/StringRef.h"
17 #include "llvm/Config/llvm-config.h"
18 #include "llvm/Support/Compiler.h"
19 #include "llvm/Support/Debug.h"
20 #include "llvm/Support/raw_ostream.h"
21 #include "llvm/TargetParser/Triple.h"
22 #include <string>
23 #include <vector>
24 
25 using namespace llvm;
26 
27 /// Splits a string of comma separated items in to a vector of strings.
28 void SubtargetFeatures::Split(std::vector<std::string> &V, StringRef S) {
29   SmallVector<StringRef, 3> Tmp;
30   S.split(Tmp, ',', -1, false /* KeepEmpty */);
31   V.reserve(Tmp.size());
32   for (StringRef T : Tmp)
33     V.push_back(std::string(T));
34 }
35 
36 void SubtargetFeatures::AddFeature(StringRef String, bool Enable) {
37   // Don't add empty features.
38   if (!String.empty())
39     // Convert to lowercase, prepend flag if we don't already have a flag.
40     Features.push_back(hasFlag(String) ? String.lower()
41                                        : (Enable ? "+" : "-") + String.lower());
42 }
43 
44 void SubtargetFeatures::addFeaturesVector(
45     const ArrayRef<std::string> OtherFeatures) {
46   Features.insert(Features.cend(), OtherFeatures.begin(), OtherFeatures.end());
47 }
48 
49 SubtargetFeatures::SubtargetFeatures(StringRef Initial) {
50   // Break up string into separate features
51   Split(Features, Initial);
52 }
53 
54 std::string SubtargetFeatures::getString() const {
55   return join(Features.begin(), Features.end(), ",");
56 }
57 
58 void SubtargetFeatures::print(raw_ostream &OS) const {
59   for (const auto &F : Features)
60     OS << F << " ";
61   OS << "\n";
62 }
63 
64 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
65 LLVM_DUMP_METHOD void SubtargetFeatures::dump() const {
66   print(dbgs());
67 }
68 #endif
69 
70 void SubtargetFeatures::getDefaultSubtargetFeatures(const Triple& Triple) {
71   // FIXME: This is an inelegant way of specifying the features of a
72   // subtarget. It would be better if we could encode this information
73   // into the IR.
74   if (Triple.getVendor() == Triple::Apple) {
75     if (Triple.getArch() == Triple::ppc) {
76       // powerpc-apple-*
77       AddFeature("altivec");
78     } else if (Triple.getArch() == Triple::ppc64) {
79       // powerpc64-apple-*
80       AddFeature("64bit");
81       AddFeature("altivec");
82     }
83   }
84 }
85