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 "CSKYTargetObjectFile.h"
17 #include "TargetInfo/CSKYTargetInfo.h"
18 #include "llvm/CodeGen/MachineFrameInfo.h"
19 #include "llvm/CodeGen/TargetLoweringObjectFileImpl.h"
20 #include "llvm/CodeGen/TargetPassConfig.h"
21 #include "llvm/CodeGen/TargetSubtargetInfo.h"
22 #include "llvm/MC/TargetRegistry.h"
23 
24 using namespace llvm;
25 
26 extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeCSKYTarget() {
27   RegisterTargetMachine<CSKYTargetMachine> X(getTheCSKYTarget());
28 
29   PassRegistry *Registry = PassRegistry::getPassRegistry();
30   initializeCSKYConstantIslandsPass(*Registry);
31 }
32 
33 static std::string computeDataLayout(const Triple &TT) {
34   std::string Ret;
35 
36   // Only support little endian for now.
37   // TODO: Add support for big endian.
38   Ret += "e";
39 
40   // CSKY is always 32-bit target with the CSKYv2 ABI as prefer now.
41   // It's a 4-byte aligned stack with ELF mangling only.
42   Ret += "-m:e-S32-p:32:32-i32:32:32-i64:32:32-f32:32:32-f64:32:32-v64:32:32"
43          "-v128:32:32-a:0:32-Fi32-n32";
44 
45   return Ret;
46 }
47 
48 CSKYTargetMachine::CSKYTargetMachine(const Target &T, const Triple &TT,
49                                      StringRef CPU, StringRef FS,
50                                      const TargetOptions &Options,
51                                      Optional<Reloc::Model> RM,
52                                      Optional<CodeModel::Model> CM,
53                                      CodeGenOpt::Level OL, bool JIT)
54     : LLVMTargetMachine(T, computeDataLayout(TT), TT, CPU, FS, Options,
55                         RM.value_or(Reloc::Static),
56                         getEffectiveCodeModel(CM, CodeModel::Small), OL),
57       TLOF(std::make_unique<CSKYELFTargetObjectFile>()) {
58   initAsmInfo();
59 }
60 
61 const CSKYSubtarget *
62 CSKYTargetMachine::getSubtargetImpl(const Function &F) const {
63   Attribute CPUAttr = F.getFnAttribute("target-cpu");
64   Attribute TuneAttr = F.getFnAttribute("tune-cpu");
65   Attribute FSAttr = F.getFnAttribute("target-features");
66 
67   std::string CPU =
68       CPUAttr.isValid() ? CPUAttr.getValueAsString().str() : TargetCPU;
69   std::string TuneCPU =
70       TuneAttr.isValid() ? TuneAttr.getValueAsString().str() : CPU;
71   std::string FS =
72       FSAttr.isValid() ? FSAttr.getValueAsString().str() : TargetFS;
73 
74   std::string Key = CPU + TuneCPU + FS;
75   auto &I = SubtargetMap[Key];
76   if (!I) {
77     // This needs to be done before we create a new subtarget since any
78     // creation will depend on the TM and the code generation flags on the
79     // function that reside in TargetOptions.
80     resetTargetOptions(F);
81     I = std::make_unique<CSKYSubtarget>(TargetTriple, CPU, TuneCPU, FS, *this);
82     if (I->useHardFloat() && !I->hasAnyFloatExt())
83       errs() << "Hard-float can't be used with current CPU,"
84                 " set to Soft-float\n";
85   }
86   return I.get();
87 }
88 
89 namespace {
90 class CSKYPassConfig : public TargetPassConfig {
91 public:
92   CSKYPassConfig(CSKYTargetMachine &TM, PassManagerBase &PM)
93       : TargetPassConfig(TM, PM) {}
94 
95   CSKYTargetMachine &getCSKYTargetMachine() const {
96     return getTM<CSKYTargetMachine>();
97   }
98 
99   void addIRPasses() override;
100   bool addInstSelector() override;
101   void addPreEmitPass() override;
102 };
103 
104 } // namespace
105 
106 TargetPassConfig *CSKYTargetMachine::createPassConfig(PassManagerBase &PM) {
107   return new CSKYPassConfig(*this, PM);
108 }
109 
110 void CSKYPassConfig::addIRPasses() {
111   addPass(createAtomicExpandPass());
112   TargetPassConfig::addIRPasses();
113 }
114 
115 bool CSKYPassConfig::addInstSelector() {
116   addPass(createCSKYISelDag(getCSKYTargetMachine()));
117 
118   return false;
119 }
120 
121 void CSKYPassConfig::addPreEmitPass() {
122   addPass(createCSKYConstantIslandPass());
123 }
124