X86JITInfo.h revision 36b56886974eae4f9c5ebc96befd3e7bfe5de338 
1//===-- X86JITInfo.h - X86 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 X86 implementation of the TargetJITInfo class.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef X86JITINFO_H
15#define X86JITINFO_H
16
17#include "llvm/CodeGen/JITCodeEmitter.h"
18#include "llvm/IR/Function.h"
19#include "llvm/Target/TargetJITInfo.h"
20
21namespace llvm {
22  class X86TargetMachine;
23  class X86Subtarget;
24
25  class X86JITInfo : public TargetJITInfo {
26    X86TargetMachine &TM;
27    const X86Subtarget *Subtarget;
28    uintptr_t PICBase;
29    char* TLSOffset;
30  public:
31    explicit X86JITInfo(X86TargetMachine &tm);
32
33    /// replaceMachineCodeForFunction - Make it so that calling the function
34    /// whose machine code is at OLD turns into a call to NEW, perhaps by
35    /// overwriting OLD with a branch to NEW.  This is used for self-modifying
36    /// code.
37    ///
38    void replaceMachineCodeForFunction(void *Old, void *New) override;
39
40    /// emitGlobalValueIndirectSym - Use the specified JITCodeEmitter object
41    /// to emit an indirect symbol which contains the address of the specified
42    /// ptr.
43    void *emitGlobalValueIndirectSym(const GlobalValue* GV, void *ptr,
44                                     JITCodeEmitter &JCE) override;
45
46    // getStubLayout - Returns the size and alignment of the largest call stub
47    // on X86.
48    StubLayout getStubLayout() override;
49
50    /// emitFunctionStub - Use the specified JITCodeEmitter object to emit a
51    /// small native function that simply calls the function at the specified
52    /// address.
53    void *emitFunctionStub(const Function* F, void *Target,
54                           JITCodeEmitter &JCE) override;
55
56    /// getPICJumpTableEntry - Returns the value of the jumptable entry for the
57    /// specific basic block.
58    uintptr_t getPICJumpTableEntry(uintptr_t BB, uintptr_t JTBase) override;
59
60    /// getLazyResolverFunction - Expose the lazy resolver to the JIT.
61    LazyResolverFn getLazyResolverFunction(JITCompilerFn) override;
62
63    /// relocate - Before the JIT can run a block of code that has been emitted,
64    /// it must rewrite the code to contain the actual addresses of any
65    /// referenced global symbols.
66    void relocate(void *Function, MachineRelocation *MR,
67                  unsigned NumRelocs, unsigned char* GOTBase) override;
68
69    /// allocateThreadLocalMemory - Each target has its own way of
70    /// handling thread local variables. This method returns a value only
71    /// meaningful to the target.
72    char* allocateThreadLocalMemory(size_t size) override;
73
74    /// setPICBase / getPICBase - Getter / setter of PICBase, used to compute
75    /// PIC jumptable entry.
76    void setPICBase(uintptr_t Base) { PICBase = Base; }
77    uintptr_t getPICBase() const { return PICBase; }
78  };
79}
80
81#endif
82