1 //===-- MipsTargetMachine.cpp - Define TargetMachine for Mips -------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // Implements the info about Mips target spec.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "Mips.h"
15 #include "MipsTargetAsmInfo.h"
16 #include "MipsTargetMachine.h"
17 #include "llvm/Module.h"
18 #include "llvm/PassManager.h"
19 #include "llvm/Target/TargetMachineRegistry.h"
20 using namespace llvm;
21 
22 /// MipsTargetMachineModule - Note that this is used on hosts that
23 /// cannot link in a library unless there are references into the
24 /// library.  In particular, it seems that it is not possible to get
25 /// things to work on Win32 without this.  Though it is unused, do not
26 /// remove it.
27 extern "C" int MipsTargetMachineModule;
28 int MipsTargetMachineModule = 0;
29 
30 // Register the target.
31 static RegisterTarget<MipsTargetMachine>    X("mips", "Mips");
32 static RegisterTarget<MipselTargetMachine>  Y("mipsel", "Mipsel");
33 
34 const TargetAsmInfo *MipsTargetMachine::
35 createTargetAsmInfo() const
36 {
37   return new MipsTargetAsmInfo(*this);
38 }
39 
40 // DataLayout --> Big-endian, 32-bit pointer/ABI/alignment
41 // The stack is always 8 byte aligned
42 // On function prologue, the stack is created by decrementing
43 // its pointer. Once decremented, all references are done with positive
44 // offset from the stack/frame pointer, using StackGrowsUp enables
45 // an easier handling.
46 // Using CodeModel::Large enables different CALL behavior.
47 MipsTargetMachine::
48 MipsTargetMachine(const Module &M, const std::string &FS, bool isLittle=false):
49   Subtarget(*this, M, FS, isLittle),
50   DataLayout(isLittle ? std::string("e-p:32:32:32-i8:8:32-i16:16:32") :
51                         std::string("E-p:32:32:32-i8:8:32-i16:16:32")),
52   InstrInfo(*this),
53   FrameInfo(TargetFrameInfo::StackGrowsUp, 8, 0),
54   TLInfo(*this)
55 {
56   // Abicall enables PIC by default
57   if (Subtarget.hasABICall())
58     setRelocationModel(Reloc::PIC_);
59 
60   // TODO: create an option to enable long calls, like -mlong-calls,
61   // that would be our CodeModel::Large. It must not work with Abicall.
62   if (getCodeModel() == CodeModel::Default)
63     setCodeModel(CodeModel::Small);
64 }
65 
66 MipselTargetMachine::
67 MipselTargetMachine(const Module &M, const std::string &FS) :
68   MipsTargetMachine(M, FS, true) {}
69 
70 // return 0 and must specify -march to gen MIPS code.
71 unsigned MipsTargetMachine::
72 getModuleMatchQuality(const Module &M)
73 {
74   // We strongly match "mips*-*".
75   std::string TT = M.getTargetTriple();
76   if (TT.size() >= 5 && std::string(TT.begin(), TT.begin()+5) == "mips-")
77     return 20;
78 
79   if (TT.size() >= 13 && std::string(TT.begin(),
80       TT.begin()+13) == "mipsallegrex-")
81     return 20;
82 
83   return 0;
84 }
85 
86 // return 0 and must specify -march to gen MIPSEL code.
87 unsigned MipselTargetMachine::
88 getModuleMatchQuality(const Module &M)
89 {
90   // We strongly match "mips*el-*".
91   std::string TT = M.getTargetTriple();
92   if (TT.size() >= 7 && std::string(TT.begin(), TT.begin()+7) == "mipsel-")
93     return 20;
94 
95   if (TT.size() >= 15 && std::string(TT.begin(),
96       TT.begin()+15) == "mipsallegrexel-")
97     return 20;
98 
99   if (TT.size() == 3 && std::string(TT.begin(), TT.begin()+3) == "psp")
100     return 20;
101 
102   return 0;
103 }
104 
105 // Install an instruction selector pass using
106 // the ISelDag to gen Mips code.
107 bool MipsTargetMachine::
108 addInstSelector(PassManagerBase &PM, CodeGenOpt::Level OptLevel)
109 {
110   PM.add(createMipsISelDag(*this));
111   return false;
112 }
113 
114 // Implemented by targets that want to run passes immediately before
115 // machine code is emitted. return true if -print-machineinstrs should
116 // print out the code after the passes.
117 bool MipsTargetMachine::
118 addPreEmitPass(PassManagerBase &PM, CodeGenOpt::Level OptLevel)
119 {
120   PM.add(createMipsDelaySlotFillerPass(*this));
121   return true;
122 }
123 
124 // Implements the AssemblyEmitter for the target. Must return
125 // true if AssemblyEmitter is supported
126 bool MipsTargetMachine::
127 addAssemblyEmitter(PassManagerBase &PM, CodeGenOpt::Level OptLevel,
128                    bool Verbose, raw_ostream &Out)
129 {
130   // Output assembly language.
131   PM.add(createMipsCodePrinterPass(Out, *this, OptLevel, Verbose));
132   return false;
133 }
134