Layer the memory manager between the JIT and the runtime Dyld.

The JITMemory manager references LLVM IR constructs directly, while the
runtime Dyld works at a lower level and can handle objects which may not
originate from LLVM IR. Introduce a new layer for the memory manager to
handle the interface between them. For the MCJIT, this layer will be almost
entirely simply a call-through w/ translation between the IR objects and
symbol names.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128851 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/ExecutionEngine/RuntimeDyld.h

@@ -21,7 +21,29 @@ namespace llvm {
 
 class RuntimeDyldImpl;
 class MemoryBuffer;
-class JITMemoryManager;
+
+// RuntimeDyld clients often want to handle the memory management of
+// what gets placed where. For JIT clients, this is an abstraction layer
+// over the JITMemoryManager, which references objects by their source
+// representations in LLVM IR.
+// FIXME: As the RuntimeDyld fills out, additional routines will be needed
+//        for the varying types of objects to be allocated.
+class RTDyldMemoryManager {
+  RTDyldMemoryManager(const RTDyldMemoryManager&);  // DO NOT IMPLEMENT
+  void operator=(const RTDyldMemoryManager&);       // DO NOT IMPLEMENT
+public:
+  RTDyldMemoryManager() {}
+
+  // Allocate ActualSize bytes, or more, for the named function. Return
+  // a pointer to the allocated memory and update Size to reflect how much
+  // memory was acutally allocated.
+  virtual uint64_t startFunctionBody(const char *Name, uintptr_t &Size) = 0;
+
+  // Mark the end of the function, including how much of the allocated
+  // memory was actually used.
+  virtual void endFunctionBody(const char *Name, uint64_t FunctionStart,
+                               uint64_t FunctionEnd) = 0;
+};
 
 class RuntimeDyld {
   RuntimeDyld(const RuntimeDyld &);     // DO NOT IMPLEMENT
@@ -31,11 +53,12 @@ class RuntimeDyld {
   // interface.
   RuntimeDyldImpl *Dyld;
 public:
-  RuntimeDyld(JITMemoryManager*);
+  RuntimeDyld(RTDyldMemoryManager*);
   ~RuntimeDyld();
 
   bool loadObject(MemoryBuffer *InputBuffer);
-  void *getSymbolAddress(StringRef Name);
+  uint64_t getSymbolAddress(StringRef Name);
+  void reassignSymbolAddress(StringRef Name, uint64_t Addr);
   // FIXME: Should be parameterized to get the memory block associated with
   // a particular loaded object.
   sys::MemoryBlock getMemoryBlock();

lib/ExecutionEngine/MCJIT/MCJIT.cpp

@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "MCJIT.h"
+#include "MCJITMemoryManager.h"
 #include "llvm/DerivedTypes.h"
 #include "llvm/Function.h"
 #include "llvm/ExecutionEngine/GenericValue.h"
@@ -57,7 +58,8 @@ ExecutionEngine *MCJIT::createJIT(Module *M,
 
   // If the target supports JIT code generation, create the JIT.
   if (TargetJITInfo *TJ = TM->getJITInfo())
-    return new MCJIT(M, TM, *TJ, JMM, OptLevel, GVsWithCode);
+    return new MCJIT(M, TM, *TJ, new MCJITMemoryManager(JMM), OptLevel,
+                     GVsWithCode);
 
   if (ErrorStr)
     *ErrorStr = "target does not support JIT code generation";
@@ -65,9 +67,9 @@ ExecutionEngine *MCJIT::createJIT(Module *M,
 }
 
 MCJIT::MCJIT(Module *m, TargetMachine *tm, TargetJITInfo &tji,
-             JITMemoryManager *JMM, CodeGenOpt::Level OptLevel,
+             RTDyldMemoryManager *MM, CodeGenOpt::Level OptLevel,
              bool AllocateGVsWithCode)
-  : ExecutionEngine(m), TM(tm), M(m), OS(Buffer), Dyld(JMM) {
+  : ExecutionEngine(m), TM(tm), MemMgr(MM), M(m), OS(Buffer), Dyld(MM) {
 
   PM.add(new TargetData(*TM->getTargetData()));
 
@@ -94,6 +96,7 @@ MCJIT::MCJIT(Module *m, TargetMachine *tm, TargetJITInfo &tji,
 }
 
 MCJIT::~MCJIT() {
+  delete MemMgr;
 }
 
 void *MCJIT::getPointerToBasicBlock(BasicBlock *BB) {
@@ -110,7 +113,7 @@ void *MCJIT::getPointerToFunction(Function *F) {
   }
 
   Twine Name = TM->getMCAsmInfo()->getGlobalPrefix() + F->getName();
-  return Dyld.getSymbolAddress(Name.str());
+  return (void*)Dyld.getSymbolAddress(Name.str());
 }
 
 void *MCJIT::recompileAndRelinkFunction(Function *F) {

lib/ExecutionEngine/MCJIT/MCJIT.h

@@ -24,11 +24,12 @@ namespace llvm {
 
 class MCJIT : public ExecutionEngine {
   MCJIT(Module *M, TargetMachine *tm, TargetJITInfo &tji,
-        JITMemoryManager *JMM, CodeGenOpt::Level OptLevel,
+        RTDyldMemoryManager *MemMgr, CodeGenOpt::Level OptLevel,
         bool AllocateGVsWithCode);
 
   TargetMachine *TM;
   MCContext *Ctx;
+  RTDyldMemoryManager *MemMgr;
 
   // FIXME: These may need moved to a separate 'jitstate' member like the
   // non-MC JIT does for multithreading and such. Just keep them here for now.

lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp

@@ -18,7 +18,6 @@
 #include "llvm/ADT/StringRef.h"
 #include "llvm/ADT/Twine.h"
 #include "llvm/ExecutionEngine/RuntimeDyld.h"
-#include "llvm/ExecutionEngine/JITMemoryManager.h"
 #include "llvm/Object/MachOObject.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/ErrorHandling.h"
@@ -35,12 +34,12 @@ class RuntimeDyldImpl {
   unsigned CPUType;
   unsigned CPUSubtype;
 
-  // The JITMemoryManager to load objects into.
-  JITMemoryManager *JMM;
+  // The MemoryManager to load objects into.
+  RTDyldMemoryManager *MemMgr;
 
   // Master symbol table. As modules are loaded and external symbols are
   // resolved, their addresses are stored here.
-  StringMap<void*> SymbolTable;
+  StringMap<uint64_t> SymbolTable;
 
   // FIXME: Should have multiple data blocks, one for each loaded chunk of
   //        compiled code.
@@ -72,11 +71,11 @@ class RuntimeDyldImpl {
                      const InMemoryStruct<macho::SymtabLoadCommand> &SymtabLC);
 
 public:
-  RuntimeDyldImpl(JITMemoryManager *jmm) : JMM(jmm), HasError(false) {}
+  RuntimeDyldImpl(RTDyldMemoryManager *mm) : MemMgr(mm), HasError(false) {}
 
   bool loadObject(MemoryBuffer *InputBuffer);
 
-  void *getSymbolAddress(StringRef Name) {
+  uint64_t getSymbolAddress(StringRef Name) {
     // Use lookup() rather than [] because we don't want to add an entry
     // if there isn't one already, which the [] operator does.
     return SymbolTable.lookup(Name);
@@ -314,7 +313,7 @@ loadSegment32(const MachOObject *Obj,
     void *SectionBase = SectionBases[Index];
 
     // Get the symbol address.
-    void *Address = (char*) SectionBase + STE->Value;
+    uint64_t Address = (uint64_t)SectionBase + STE->Value;
 
     // FIXME: Check the symbol type and flags.
     if (STE->Type != 0xF)
@@ -335,7 +334,7 @@ loadSegment32(const MachOObject *Obj,
   }
 
   // We've loaded the section; now mark the functions in it as executable.
-  // FIXME: We really should use the JITMemoryManager for this.
+  // FIXME: We really should use the MemoryManager for this.
   sys::Memory::setRangeExecutable(Data.base(), Data.size());
 
   return false;
@@ -414,7 +413,7 @@ loadSegment64(const MachOObject *Obj,
     void *SectionBase = SectionBases[Index];
 
     // Get the symbol address.
-    void *Address = (char*) SectionBase + STE->Value;
+    uint64_t Address = (uint64_t) SectionBase + STE->Value;
 
     // FIXME: Check the symbol type and flags.
     if (STE->Type != 0xF)
@@ -434,7 +433,7 @@ loadSegment64(const MachOObject *Obj,
   }
 
   // We've loaded the section; now mark the functions in it as executable.
-  // FIXME: We really should use the JITMemoryManager for this.
+  // FIXME: We really should use the MemoryManager for this.
   sys::Memory::setRangeExecutable(Data.base(), Data.size());
 
   return false;
@@ -530,8 +529,8 @@ bool RuntimeDyldImpl::loadObject(MemoryBuffer *InputBuffer) {
 
 //===----------------------------------------------------------------------===//
 // RuntimeDyld class implementation
-RuntimeDyld::RuntimeDyld(JITMemoryManager *JMM) {
-  Dyld = new RuntimeDyldImpl(JMM);
+RuntimeDyld::RuntimeDyld(RTDyldMemoryManager *MM) {
+  Dyld = new RuntimeDyldImpl(MM);
 }
 
 RuntimeDyld::~RuntimeDyld() {
@@ -542,7 +541,7 @@ bool RuntimeDyld::loadObject(MemoryBuffer *InputBuffer) {
   return Dyld->loadObject(InputBuffer);
 }
 
-void *RuntimeDyld::getSymbolAddress(StringRef Name) {
+uint64_t RuntimeDyld::getSymbolAddress(StringRef Name) {
   return Dyld->getSymbolAddress(Name);
 }
 

tools/llvm-rtdyld/llvm-rtdyld.cpp

@@ -13,7 +13,6 @@
 
 #include "llvm/ADT/StringMap.h"
 #include "llvm/ADT/OwningPtr.h"
-#include "llvm/ExecutionEngine/JITMemoryManager.h"
 #include "llvm/ExecutionEngine/RuntimeDyld.h"
 #include "llvm/Object/MachOObject.h"
 #include "llvm/Support/CommandLine.h"
@@ -41,6 +40,20 @@ Action(cl::desc("Action to perform:"),
 
 /* *** */
 
+// A trivial memory manager that doesn't do anything fancy, just uses the
+// support library allocation routines directly.
+class TrivialMemoryManager : public RTDyldMemoryManager {
+public:
+  uint64_t startFunctionBody(const char *Name, uintptr_t &Size);
+  void endFunctionBody(const char *Name, uint64_t FunctionStart,
+                       uint64_t FunctionEnd) {}
+};
+
+uint64_t TrivialMemoryManager::startFunctionBody(const char *Name,
+                                                 uintptr_t &Size) {
+  return (uint64_t)sys::Memory::AllocateRWX(Size, 0, 0).base();
+}
+
 static const char *ProgramName;
 
 static void Message(const char *Type, const Twine &Msg) {
@@ -61,7 +74,7 @@ static int executeInput() {
     return Error("unable to read input: '" + ec.message() + "'");
 
   // Instantiate a dynamic linker.
-  RuntimeDyld Dyld(JITMemoryManager::CreateDefaultMemManager());
+  RuntimeDyld Dyld(new TrivialMemoryManager);
 
   // Load the object file into it.
   if (Dyld.loadObject(InputBuffer.take())) {
@@ -69,7 +82,7 @@ static int executeInput() {
   }
 
   // Get the address of "_main".
-  void *MainAddress = Dyld.getSymbolAddress("_main");
+  uint64_t MainAddress = Dyld.getSymbolAddress("_main");
   if (MainAddress == 0)
     return Error("no definition for '_main'");
 
@@ -83,7 +96,7 @@ static int executeInput() {
     return Error("unable to mark function executable: '" + ErrorStr + "'");
 
   // Dispatch to _main().
-  errs() << "loaded '_main' at: " << MainAddress << "\n";
+  errs() << "loaded '_main' at: " << (void*)MainAddress << "\n";
 
   int (*Main)(int, const char**) =
     (int(*)(int,const char**)) uintptr_t(MainAddress);