Improved support in RuntimeDyldMachO for generating
authorSean Callanan <scallanan@apple.com>
Wed, 7 Mar 2012 23:05:25 +0000 (23:05 +0000)
committerSean Callanan <scallanan@apple.com>
Wed, 7 Mar 2012 23:05:25 +0000 (23:05 +0000)
code that will be relocated into another memory space.
Now when relocations are resolved, the address of
the relocation in the host memory (where the JIT is)
is passed separately from the address that the
relocation will be at in the target memory (where
the code will run).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152264 91177308-0d34-0410-b5e6-96231b3b80d8

lib/ExecutionEngine/RuntimeDyld/RuntimeDyldMachO.cpp
lib/ExecutionEngine/RuntimeDyld/RuntimeDyldMachO.h

index c11b2c31c3fec7251a73adfe98d5945d69aeb23e..e96a68925a0e1c08e6a27a23bfc1cbddd2cf1218 100644 (file)
@@ -22,29 +22,49 @@ using namespace llvm::object;
 namespace llvm {
 
 bool RuntimeDyldMachO::
-resolveRelocation(uint8_t *Address, uint64_t Value, bool isPCRel,
-                  unsigned Type, unsigned Size, int64_t Addend) {
+resolveRelocation(uint8_t *LocalAddress,
+                  uint64_t FinalAddress,
+                  uint64_t Value,
+                  bool isPCRel,
+                  unsigned Type,
+                  unsigned Size,
+                  int64_t Addend) {
   // This just dispatches to the proper target specific routine.
   switch (CPUType) {
   default: llvm_unreachable("Unsupported CPU type!");
   case mach::CTM_x86_64:
-    return resolveX86_64Relocation((uintptr_t)Address, (uintptr_t)Value,
-                                   isPCRel, Type, Size, Addend);
+    return resolveX86_64Relocation(LocalAddress,
+                                   FinalAddress,
+                                   (uintptr_t)Value,
+                                   isPCRel,
+                                   Type,
+                                   Size,
+                                   Addend);
   case mach::CTM_ARM:
-    return resolveARMRelocation((uintptr_t)Address, (uintptr_t)Value,
-                                isPCRel, Type, Size, Addend);
+    return resolveARMRelocation(LocalAddress,
+                                FinalAddress,
+                                (uintptr_t)Value,
+                                isPCRel,
+                                Type,
+                                Size,
+                                Addend);
   }
 }
 
 bool RuntimeDyldMachO::
-resolveX86_64Relocation(uintptr_t Address, uintptr_t Value, bool isPCRel,
-                        unsigned Type, unsigned Size, int64_t Addend) {
+resolveX86_64Relocation(uint8_t *LocalAddress,
+                        uint64_t FinalAddress,
+                        uint64_t Value,
+                        bool isPCRel,
+                        unsigned Type,
+                        unsigned Size,
+                        int64_t Addend) {
   // If the relocation is PC-relative, the value to be encoded is the
   // pointer difference.
   if (isPCRel)
     // FIXME: It seems this value needs to be adjusted by 4 for an effective PC
     // address. Is that expected? Only for branches, perhaps?
-    Value -= Address + 4;
+    Value -= FinalAddress + 4;
 
   switch(Type) {
   default:
@@ -58,7 +78,7 @@ resolveX86_64Relocation(uintptr_t Address, uintptr_t Value, bool isPCRel,
     Value += Addend;
     // Mask in the target value a byte at a time (we don't have an alignment
     // guarantee for the target address, so this is safest).
-    uint8_t *p = (uint8_t*)Address;
+    uint8_t *p = (uint8_t*)LocalAddress;
     for (unsigned i = 0; i < Size; ++i) {
       *p++ = (uint8_t)Value;
       Value >>= 8;
@@ -74,12 +94,17 @@ resolveX86_64Relocation(uintptr_t Address, uintptr_t Value, bool isPCRel,
 }
 
 bool RuntimeDyldMachO::
-resolveARMRelocation(uintptr_t Address, uintptr_t Value, bool isPCRel,
-                     unsigned Type, unsigned Size, int64_t Addend) {
+resolveARMRelocation(uint8_t *LocalAddress,
+                     uint64_t FinalAddress,
+                     uint64_t Value,
+                     bool isPCRel,
+                     unsigned Type,
+                     unsigned Size,
+                     int64_t Addend) {
   // If the relocation is PC-relative, the value to be encoded is the
   // pointer difference.
   if (isPCRel) {
-    Value -= Address;
+    Value -= FinalAddress;
     // ARM PCRel relocations have an effective-PC offset of two instructions
     // (four bytes in Thumb mode, 8 bytes in ARM mode).
     // FIXME: For now, assume ARM mode.
@@ -92,7 +117,7 @@ resolveARMRelocation(uintptr_t Address, uintptr_t Value, bool isPCRel,
   case macho::RIT_Vanilla: {
     // Mask in the target value a byte at a time (we don't have an alignment
     // guarantee for the target address, so this is safest).
-    uint8_t *p = (uint8_t*)Address;
+    uint8_t *p = (uint8_t*)LocalAddress;
     for (unsigned i = 0; i < Size; ++i) {
       *p++ = (uint8_t)Value;
       Value >>= 8;
@@ -102,7 +127,7 @@ resolveARMRelocation(uintptr_t Address, uintptr_t Value, bool isPCRel,
   case macho::RIT_ARM_Branch24Bit: {
     // Mask the value into the target address. We know instructions are
     // 32-bit aligned, so we can do it all at once.
-    uint32_t *p = (uint32_t*)Address;
+    uint32_t *p = (uint32_t*)LocalAddress;
     // The low two bits of the value are not encoded.
     Value >>= 2;
     // Mask the value to 24 bits.
@@ -569,6 +594,7 @@ void RuntimeDyldMachO::reassignSectionAddress(unsigned SectionID,
   for (unsigned i = 0, e = Relocs.size(); i != e; ++i) {
     RelocationEntry &RE = Relocs[i];
     uint8_t *Target = (uint8_t*)Sections[RE.SectionID].base() + RE.Offset;
+    uint64_t FinalTarget = (uint64_t)SectionLoadAddress[RE.SectionID] + RE.Offset;
     bool isPCRel = (RE.Data >> 24) & 1;
     unsigned Type = (RE.Data >> 28) & 0xf;
     unsigned Size = 1 << ((RE.Data >> 25) & 3);
@@ -580,7 +606,13 @@ void RuntimeDyldMachO::reassignSectionAddress(unsigned SectionID,
           << ", type: " << Type << ", Size: " << Size << ", Addend: "
           << RE.Addend << ").\n");
 
-    resolveRelocation(Target, Addr, isPCRel, Type, Size, RE.Addend);
+    resolveRelocation(Target,
+                      FinalTarget,
+                      Addr,
+                      isPCRel,
+                      Type,
+                      Size,
+                      RE.Addend);
   }
 }
 
index 57989811c80b36320d83c5d55dc7a932e151ca34..09803cff74841bc1663b6bb5cfdb4f64052647f7 100644 (file)
@@ -51,12 +51,27 @@ class RuntimeDyldMachO : public RuntimeDyldImpl {
   // relocations by definition. Indexed by symbol name.
   StringMap<RelocationList> UnresolvedRelocations;
 
-  bool resolveRelocation(uint8_t *Address, uint64_t Value, bool isPCRel,
-                         unsigned Type, unsigned Size, int64_t Addend);
-  bool resolveX86_64Relocation(uintptr_t Address, uintptr_t Value, bool isPCRel,
-                               unsigned Type, unsigned Size, int64_t Addend);
-  bool resolveARMRelocation(uintptr_t Address, uintptr_t Value, bool isPCRel,
-                            unsigned Type, unsigned Size, int64_t Addend);
+  bool resolveRelocation(uint8_t *LocalAddress,
+                         uint64_t FinalAddress,
+                         uint64_t Value,
+                         bool isPCRel,
+                         unsigned Type,
+                         unsigned Size,
+                         int64_t Addend);
+  bool resolveX86_64Relocation(uint8_t *LocalAddress,
+                               uint64_t FinalAddress,
+                               uint64_t Value,
+                               bool isPCRel,
+                               unsigned Type,
+                               unsigned Size,
+                               int64_t Addend);
+  bool resolveARMRelocation(uint8_t *LocalAddress,
+                            uint64_t FinalAddress,
+                            uint64_t Value,
+                            bool isPCRel,
+                            unsigned Type,
+                            unsigned Size,
+                            int64_t Addend);
 
   bool loadSegment32(const MachOObject *Obj,
                      const MachOObject::LoadCommandInfo *SegmentLCI,