1 //===--- CSKYTargetMachine.cpp - Define TargetMachine for CSKY ------------===//
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 // Implements the info about CSKY target spec.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "CSKYTargetMachine.h"
14 #include "CSKY.h"
15 #include "CSKYSubtarget.h"
16 #include "TargetInfo/CSKYTargetInfo.h"
17 #include "llvm/CodeGen/MachineFrameInfo.h"
18 #include "llvm/CodeGen/TargetLoweringObjectFileImpl.h"
19 #include "llvm/CodeGen/TargetPassConfig.h"
20 #include "llvm/CodeGen/TargetSubtargetInfo.h"
21 #include "llvm/MC/TargetRegistry.h"
22 
23 using namespace llvm;
24 
25 extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeCSKYTarget() {
26   RegisterTargetMachine<CSKYTargetMachine> X(getTheCSKYTarget());
27 
28   PassRegistry *Registry = PassRegistry::getPassRegistry();
29   initializeCSKYConstantIslandsPass(*Registry);
30 }
31 
32 static std::string computeDataLayout(const Triple &TT) {
33   std::string Ret;
34 
35   // Only support little endian for now.
36   // TODO: Add support for big endian.
37   Ret += "e";
38 
39   // CSKY is always 32-bit target with the CSKYv2 ABI as prefer now.
40   // It's a 4-byte aligned stack with ELF mangling only.
41   Ret += "-m:e-S32-p:32:32-i32:32:32-i64:32:32-f32:32:32-f64:32:32-v64:32:32"
42          "-v128:32:32-a:0:32-Fi32-n32";
43 
44   return Ret;
45 }
46 
47 CSKYTargetMachine::CSKYTargetMachine(const Target &T, const Triple &TT,
48                                      StringRef CPU, StringRef FS,
49                                      const TargetOptions &Options,
50                                      Optional<Reloc::Model> RM,
51                                      Optional<CodeModel::Model> CM,
52                                      CodeGenOpt::Level OL, bool JIT)
53     : LLVMTargetMachine(T, computeDataLayout(TT), TT, CPU, FS, Options,
54                         RM.getValueOr(Reloc::Static),
55                         getEffectiveCodeModel(CM, CodeModel::Small), OL),
56       TLOF(std::make_unique<TargetLoweringObjectFileELF>()) {
57   initAsmInfo();
58 }
59 
60 const CSKYSubtarget *
61 CSKYTargetMachine::getSubtargetImpl(const Function &F) const {
62   Attribute CPUAttr = F.getFnAttribute("target-cpu");
63   Attribute TuneAttr = F.getFnAttribute("tune-cpu");
64   Attribute FSAttr = F.getFnAttribute("target-features");
65 
66   std::string CPU =
67       CPUAttr.isValid() ? CPUAttr.getValueAsString().str() : TargetCPU;
68   std::string TuneCPU =
69       TuneAttr.isValid() ? TuneAttr.getValueAsString().str() : CPU;
70   std::string FS =
71       FSAttr.isValid() ? FSAttr.getValueAsString().str() : TargetFS;
72 
73   std::string Key = CPU + TuneCPU + FS;
74   auto &I = SubtargetMap[Key];
75   if (!I) {
76     // This needs to be done before we create a new subtarget since any
77     // creation will depend on the TM and the code generation flags on the
78     // function that reside in TargetOptions.
79     resetTargetOptions(F);
80     I = std::make_unique<CSKYSubtarget>(TargetTriple, CPU, TuneCPU, FS, *this);
81     if (I->useHardFloat() && !I->hasAnyFloatExt())
82       errs() << "Hard-float can't be used with current CPU,"
83                 " set to Soft-float\n";
84   }
85   return I.get();
86 }
87 
88 namespace {
89 class CSKYPassConfig : public TargetPassConfig {
90 public:
91   CSKYPassConfig(CSKYTargetMachine &TM, PassManagerBase &PM)
92       : TargetPassConfig(TM, PM) {}
93 
94   CSKYTargetMachine &getCSKYTargetMachine() const {
95     return getTM<CSKYTargetMachine>();
96   }
97 
98   bool addInstSelector() override;
99   void addPreEmitPass() override;
100 };
101 
102 } // namespace
103 
104 TargetPassConfig *CSKYTargetMachine::createPassConfig(PassManagerBase &PM) {
105   return new CSKYPassConfig(*this, PM);
106 }
107 
108 bool CSKYPassConfig::addInstSelector() {
109   addPass(createCSKYISelDag(getCSKYTargetMachine()));
110 
111   return false;
112 }
113 
114 void CSKYPassConfig::addPreEmitPass() {
115   addPass(createCSKYConstantIslandPass());
116 }
117