xref: /freebsd/contrib/llvm-project/llvm/lib/Target/RISCV/RISCVTargetMachine.cpp (revision 0b37c1590418417c894529d371800dfac71ef887)
1 //===-- RISCVTargetMachine.cpp - Define TargetMachine for RISCV -----------===//
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 RISCV target spec.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "RISCVTargetMachine.h"
14 #include "RISCV.h"
15 #include "RISCVTargetObjectFile.h"
16 #include "RISCVTargetTransformInfo.h"
17 #include "TargetInfo/RISCVTargetInfo.h"
18 #include "llvm/ADT/STLExtras.h"
19 #include "llvm/Analysis/TargetTransformInfo.h"
20 #include "llvm/CodeGen/GlobalISel/IRTranslator.h"
21 #include "llvm/CodeGen/GlobalISel/InstructionSelect.h"
22 #include "llvm/CodeGen/GlobalISel/Legalizer.h"
23 #include "llvm/CodeGen/GlobalISel/RegBankSelect.h"
24 #include "llvm/CodeGen/Passes.h"
25 #include "llvm/CodeGen/TargetLoweringObjectFileImpl.h"
26 #include "llvm/CodeGen/TargetPassConfig.h"
27 #include "llvm/IR/LegacyPassManager.h"
28 #include "llvm/InitializePasses.h"
29 #include "llvm/Support/FormattedStream.h"
30 #include "llvm/Support/TargetRegistry.h"
31 #include "llvm/Target/TargetOptions.h"
32 using namespace llvm;
33 
34 extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeRISCVTarget() {
35   RegisterTargetMachine<RISCVTargetMachine> X(getTheRISCV32Target());
36   RegisterTargetMachine<RISCVTargetMachine> Y(getTheRISCV64Target());
37   auto PR = PassRegistry::getPassRegistry();
38   initializeGlobalISel(*PR);
39   initializeRISCVExpandPseudoPass(*PR);
40 }
41 
42 static StringRef computeDataLayout(const Triple &TT) {
43   if (TT.isArch64Bit()) {
44     return "e-m:e-p:64:64-i64:64-i128:128-n64-S128";
45   } else {
46     assert(TT.isArch32Bit() && "only RV32 and RV64 are currently supported");
47     return "e-m:e-p:32:32-i64:64-n32-S128";
48   }
49 }
50 
51 static Reloc::Model getEffectiveRelocModel(const Triple &TT,
52                                            Optional<Reloc::Model> RM) {
53   if (!RM.hasValue())
54     return Reloc::Static;
55   return *RM;
56 }
57 
58 RISCVTargetMachine::RISCVTargetMachine(const Target &T, const Triple &TT,
59                                        StringRef CPU, StringRef FS,
60                                        const TargetOptions &Options,
61                                        Optional<Reloc::Model> RM,
62                                        Optional<CodeModel::Model> CM,
63                                        CodeGenOpt::Level OL, bool JIT)
64     : LLVMTargetMachine(T, computeDataLayout(TT), TT, CPU, FS, Options,
65                         getEffectiveRelocModel(TT, RM),
66                         getEffectiveCodeModel(CM, CodeModel::Small), OL),
67       TLOF(std::make_unique<RISCVELFTargetObjectFile>()) {
68   initAsmInfo();
69 
70   // RISC-V supports the MachineOutliner.
71   setMachineOutliner(true);
72 }
73 
74 const RISCVSubtarget *
75 RISCVTargetMachine::getSubtargetImpl(const Function &F) const {
76   Attribute CPUAttr = F.getFnAttribute("target-cpu");
77   Attribute FSAttr = F.getFnAttribute("target-features");
78 
79   std::string CPU = !CPUAttr.hasAttribute(Attribute::None)
80                         ? CPUAttr.getValueAsString().str()
81                         : TargetCPU;
82   std::string FS = !FSAttr.hasAttribute(Attribute::None)
83                        ? FSAttr.getValueAsString().str()
84                        : TargetFS;
85   std::string Key = CPU + FS;
86   auto &I = SubtargetMap[Key];
87   if (!I) {
88     // This needs to be done before we create a new subtarget since any
89     // creation will depend on the TM and the code generation flags on the
90     // function that reside in TargetOptions.
91     resetTargetOptions(F);
92     I = std::make_unique<RISCVSubtarget>(TargetTriple, CPU, FS,
93                                          Options.MCOptions.getABIName(), *this);
94   }
95   return I.get();
96 }
97 
98 TargetTransformInfo
99 RISCVTargetMachine::getTargetTransformInfo(const Function &F) {
100   return TargetTransformInfo(RISCVTTIImpl(this, F));
101 }
102 
103 namespace {
104 class RISCVPassConfig : public TargetPassConfig {
105 public:
106   RISCVPassConfig(RISCVTargetMachine &TM, PassManagerBase &PM)
107       : TargetPassConfig(TM, PM) {}
108 
109   RISCVTargetMachine &getRISCVTargetMachine() const {
110     return getTM<RISCVTargetMachine>();
111   }
112 
113   void addIRPasses() override;
114   bool addInstSelector() override;
115   bool addIRTranslator() override;
116   bool addLegalizeMachineIR() override;
117   bool addRegBankSelect() override;
118   bool addGlobalInstructionSelect() override;
119   void addPreEmitPass() override;
120   void addPreEmitPass2() override;
121   void addPreRegAlloc() override;
122 };
123 }
124 
125 TargetPassConfig *RISCVTargetMachine::createPassConfig(PassManagerBase &PM) {
126   return new RISCVPassConfig(*this, PM);
127 }
128 
129 void RISCVPassConfig::addIRPasses() {
130   addPass(createAtomicExpandPass());
131   TargetPassConfig::addIRPasses();
132 }
133 
134 bool RISCVPassConfig::addInstSelector() {
135   addPass(createRISCVISelDag(getRISCVTargetMachine()));
136 
137   return false;
138 }
139 
140 bool RISCVPassConfig::addIRTranslator() {
141   addPass(new IRTranslator());
142   return false;
143 }
144 
145 bool RISCVPassConfig::addLegalizeMachineIR() {
146   addPass(new Legalizer());
147   return false;
148 }
149 
150 bool RISCVPassConfig::addRegBankSelect() {
151   addPass(new RegBankSelect());
152   return false;
153 }
154 
155 bool RISCVPassConfig::addGlobalInstructionSelect() {
156   addPass(new InstructionSelect());
157   return false;
158 }
159 
160 void RISCVPassConfig::addPreEmitPass() { addPass(&BranchRelaxationPassID); }
161 
162 void RISCVPassConfig::addPreEmitPass2() {
163   // Schedule the expansion of AMOs at the last possible moment, avoiding the
164   // possibility for other passes to break the requirements for forward
165   // progress in the LR/SC block.
166   addPass(createRISCVExpandPseudoPass());
167 }
168 
169 void RISCVPassConfig::addPreRegAlloc() {
170   addPass(createRISCVMergeBaseOffsetOptPass());
171 }
172