• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 //===- ARMJITInfo.h - ARM implementation of the JIT interface  --*- C++ -*-===//
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 // This file contains the declaration of the ARMJITInfo class.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef ARMJITINFO_H
15 #define ARMJITINFO_H
16 
17 #include "ARMMachineFunctionInfo.h"
18 #include "llvm/CodeGen/MachineConstantPool.h"
19 #include "llvm/CodeGen/MachineFunction.h"
20 #include "llvm/CodeGen/MachineJumpTableInfo.h"
21 #include "llvm/Target/TargetJITInfo.h"
22 #include "llvm/ADT/DenseMap.h"
23 #include "llvm/ADT/SmallVector.h"
24 
25 namespace llvm {
26   class ARMTargetMachine;
27 
28   class ARMJITInfo : public TargetJITInfo {
29     // ConstPoolId2AddrMap - A map from constant pool ids to the corresponding
30     // CONSTPOOL_ENTRY addresses.
31     SmallVector<intptr_t, 16> ConstPoolId2AddrMap;
32 
33     // JumpTableId2AddrMap - A map from inline jumptable ids to the
34     // corresponding inline jump table bases.
35     SmallVector<intptr_t, 16> JumpTableId2AddrMap;
36 
37     // PCLabelMap - A map from PC labels to addresses.
38     DenseMap<unsigned, intptr_t> PCLabelMap;
39 
40     // Sym2IndirectSymMap - A map from symbol (GlobalValue and ExternalSymbol)
41     // addresses to their indirect symbol addresses.
42     DenseMap<void*, intptr_t> Sym2IndirectSymMap;
43 
44     // IsPIC - True if the relocation model is PIC. This is used to determine
45     // how to codegen function stubs.
46     bool IsPIC;
47 
48   public:
ARMJITInfo()49     explicit ARMJITInfo() : IsPIC(false) { useGOT = false; }
50 
51     /// replaceMachineCodeForFunction - Make it so that calling the function
52     /// whose machine code is at OLD turns into a call to NEW, perhaps by
53     /// overwriting OLD with a branch to NEW.  This is used for self-modifying
54     /// code.
55     ///
56     virtual void replaceMachineCodeForFunction(void *Old, void *New);
57 
58     /// emitGlobalValueIndirectSym - Use the specified JITCodeEmitter object
59     /// to emit an indirect symbol which contains the address of the specified
60     /// ptr.
61     virtual void *emitGlobalValueIndirectSym(const GlobalValue* GV, void *ptr,
62                                             JITCodeEmitter &JCE);
63 
64     // getStubLayout - Returns the size and alignment of the largest call stub
65     // on ARM.
66     virtual StubLayout getStubLayout();
67 
68     /// emitFunctionStub - Use the specified JITCodeEmitter object to emit a
69     /// small native function that simply calls the function at the specified
70     /// address.
71     virtual void *emitFunctionStub(const Function* F, void *Fn,
72                                    JITCodeEmitter &JCE);
73 
74     /// getLazyResolverFunction - Expose the lazy resolver to the JIT.
75     virtual LazyResolverFn getLazyResolverFunction(JITCompilerFn);
76 
77     /// relocate - Before the JIT can run a block of code that has been emitted,
78     /// it must rewrite the code to contain the actual addresses of any
79     /// referenced global symbols.
80     virtual void relocate(void *Function, MachineRelocation *MR,
81                           unsigned NumRelocs, unsigned char* GOTBase);
82 
83     /// hasCustomConstantPool - Allows a target to specify that constant
84     /// pool address resolution is handled by the target.
hasCustomConstantPool()85     virtual bool hasCustomConstantPool() const { return true; }
86 
87     /// hasCustomJumpTables - Allows a target to specify that jumptables
88     /// are emitted by the target.
hasCustomJumpTables()89     virtual bool hasCustomJumpTables() const { return true; }
90 
91     /// allocateSeparateGVMemory - If true, globals should be placed in
92     /// separately allocated heap memory rather than in the same
93     /// code memory allocated by JITCodeEmitter.
allocateSeparateGVMemory()94     virtual bool allocateSeparateGVMemory() const {
95 #ifdef __APPLE__
96       return true;
97 #else
98       return false;
99 #endif
100     }
101 
102     /// Initialize - Initialize internal stage for the function being JITted.
103     /// Resize constant pool ids to CONSTPOOL_ENTRY addresses map; resize
104     /// jump table ids to jump table bases map; remember if codegen relocation
105     /// model is PIC.
Initialize(const MachineFunction & MF,bool isPIC)106     void Initialize(const MachineFunction &MF, bool isPIC) {
107       const ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
108       ConstPoolId2AddrMap.resize(AFI->getNumPICLabels());
109       JumpTableId2AddrMap.resize(AFI->getNumJumpTables());
110       IsPIC = isPIC;
111     }
112 
113     /// getConstantPoolEntryAddr - The ARM target puts all constant
114     /// pool entries into constant islands. This returns the address of the
115     /// constant pool entry of the specified index.
getConstantPoolEntryAddr(unsigned CPI)116     intptr_t getConstantPoolEntryAddr(unsigned CPI) const {
117       assert(CPI < ConstPoolId2AddrMap.size());
118       return ConstPoolId2AddrMap[CPI];
119     }
120 
121     /// addConstantPoolEntryAddr - Map a Constant Pool Index to the address
122     /// where its associated value is stored. When relocations are processed,
123     /// this value will be used to resolve references to the constant.
addConstantPoolEntryAddr(unsigned CPI,intptr_t Addr)124     void addConstantPoolEntryAddr(unsigned CPI, intptr_t Addr) {
125       assert(CPI < ConstPoolId2AddrMap.size());
126       ConstPoolId2AddrMap[CPI] = Addr;
127     }
128 
129     /// getJumpTableBaseAddr - The ARM target inline all jump tables within
130     /// text section of the function. This returns the address of the base of
131     /// the jump table of the specified index.
getJumpTableBaseAddr(unsigned JTI)132     intptr_t getJumpTableBaseAddr(unsigned JTI) const {
133       assert(JTI < JumpTableId2AddrMap.size());
134       return JumpTableId2AddrMap[JTI];
135     }
136 
137     /// addJumpTableBaseAddr - Map a jump table index to the address where
138     /// the corresponding inline jump table is emitted. When relocations are
139     /// processed, this value will be used to resolve references to the
140     /// jump table.
addJumpTableBaseAddr(unsigned JTI,intptr_t Addr)141     void addJumpTableBaseAddr(unsigned JTI, intptr_t Addr) {
142       assert(JTI < JumpTableId2AddrMap.size());
143       JumpTableId2AddrMap[JTI] = Addr;
144     }
145 
146     /// getPCLabelAddr - Retrieve the address of the PC label of the
147     /// specified id.
getPCLabelAddr(unsigned Id)148     intptr_t getPCLabelAddr(unsigned Id) const {
149       DenseMap<unsigned, intptr_t>::const_iterator I = PCLabelMap.find(Id);
150       assert(I != PCLabelMap.end());
151       return I->second;
152     }
153 
154     /// addPCLabelAddr - Remember the address of the specified PC label.
addPCLabelAddr(unsigned Id,intptr_t Addr)155     void addPCLabelAddr(unsigned Id, intptr_t Addr) {
156       PCLabelMap.insert(std::make_pair(Id, Addr));
157     }
158 
159     /// getIndirectSymAddr - Retrieve the address of the indirect symbol of the
160     /// specified symbol located at address. Returns 0 if the indirect symbol
161     /// has not been emitted.
getIndirectSymAddr(void * Addr)162     intptr_t getIndirectSymAddr(void *Addr) const {
163       DenseMap<void*,intptr_t>::const_iterator I= Sym2IndirectSymMap.find(Addr);
164       if (I != Sym2IndirectSymMap.end())
165         return I->second;
166       return 0;
167     }
168 
169     /// addIndirectSymAddr - Add a mapping from address of an emitted symbol to
170     /// its indirect symbol address.
addIndirectSymAddr(void * SymAddr,intptr_t IndSymAddr)171     void addIndirectSymAddr(void *SymAddr, intptr_t IndSymAddr) {
172       Sym2IndirectSymMap.insert(std::make_pair(SymAddr, IndSymAddr));
173     }
174 
175   private:
176     /// resolveRelocDestAddr - Resolve the resulting address of the relocation
177     /// if it's not already solved. Constantpool entries must be resolved by
178     /// ARM target.
179     intptr_t resolveRelocDestAddr(MachineRelocation *MR) const;
180   };
181 }
182 
183 #endif
184