OrcTargetSupport.cpp [plain text]
#include "llvm/ADT/Triple.h"
#include "llvm/ExecutionEngine/Orc/OrcTargetSupport.h"
#include "llvm/Support/Process.h"
#include <array>
namespace llvm {
namespace orc {
void OrcX86_64::writeResolverCode(uint8_t *ResolverMem, JITReentryFn ReentryFn,
void *CallbackMgr) {
const uint8_t ResolverCode[] = {
0x55, 0x48, 0x89, 0xe5, 0x50, 0x53, 0x51, 0x52, 0x56, 0x57, 0x41, 0x50, 0x41, 0x51, 0x41, 0x52, 0x41, 0x53, 0x41, 0x54, 0x41, 0x55, 0x41, 0x56, 0x41, 0x57, 0x48, 0x81, 0xec, 0x08, 0x02, 0x00, 0x00, 0x48, 0x0f, 0xae, 0x04, 0x24, 0x48, 0x8d, 0x3d, 0x43, 0x00, 0x00, 0x00, 0x48, 0x8b, 0x3f, 0x48, 0x8b, 0x75, 0x08, 0x48, 0x83, 0xee, 0x06, 0x48, 0xb8,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0xff, 0xd0, 0x48, 0x89, 0x45, 0x08, 0x48, 0x0f, 0xae, 0x0c, 0x24, 0x48, 0x81, 0xc4, 0x08, 0x02, 0x00, 0x00, 0x41, 0x5f, 0x41, 0x5e, 0x41, 0x5d, 0x41, 0x5c, 0x41, 0x5b, 0x41, 0x5a, 0x41, 0x59, 0x41, 0x58, 0x5f, 0x5e, 0x5a, 0x59, 0x5b, 0x58, 0x5d, 0xc3, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
};
const unsigned ReentryFnAddrOffset = 0x3a;
const unsigned CallbackMgrAddrOffset = 0x70;
memcpy(ResolverMem, ResolverCode, sizeof(ResolverCode));
memcpy(ResolverMem + ReentryFnAddrOffset, &ReentryFn, sizeof(ReentryFn));
memcpy(ResolverMem + CallbackMgrAddrOffset, &CallbackMgr,
sizeof(CallbackMgr));
}
void OrcX86_64::writeTrampolines(uint8_t *TrampolineMem, void *ResolverAddr,
unsigned NumTrampolines) {
unsigned OffsetToPtr = NumTrampolines * TrampolineSize;
memcpy(TrampolineMem + OffsetToPtr, &ResolverAddr, sizeof(void*));
uint64_t *Trampolines = reinterpret_cast<uint64_t*>(TrampolineMem);
uint64_t CallIndirPCRel = 0xf1c40000000015ff;
for (unsigned I = 0; I < NumTrampolines; ++I, OffsetToPtr -= TrampolineSize)
Trampolines[I] = CallIndirPCRel | ((OffsetToPtr - 6) << 16);
}
std::error_code OrcX86_64::emitIndirectStubsBlock(IndirectStubsInfo &StubsInfo,
unsigned MinStubs,
void *InitialPtrVal) {
const unsigned StubSize = IndirectStubsInfo::StubSize;
unsigned PageSize = sys::Process::getPageSize();
unsigned NumPages = ((MinStubs * StubSize) + (PageSize - 1)) / PageSize;
unsigned NumStubs = (NumPages * PageSize) / StubSize;
std::error_code EC;
auto StubsMem =
sys::OwningMemoryBlock(
sys::Memory::allocateMappedMemory(2 * NumPages * PageSize, nullptr,
sys::Memory::MF_READ |
sys::Memory::MF_WRITE,
EC));
if (EC)
return EC;
sys::MemoryBlock StubsBlock(StubsMem.base(), NumPages * PageSize);
sys::MemoryBlock PtrsBlock(static_cast<char*>(StubsMem.base()) +
NumPages * PageSize,
NumPages * PageSize);
uint64_t *Stub = reinterpret_cast<uint64_t*>(StubsBlock.base());
uint64_t PtrOffsetField =
static_cast<uint64_t>(NumPages * PageSize - 6) << 16;
for (unsigned I = 0; I < NumStubs; ++I)
Stub[I] = 0xF1C40000000025ff | PtrOffsetField;
if (auto EC = sys::Memory::protectMappedMemory(StubsBlock,
sys::Memory::MF_READ |
sys::Memory::MF_EXEC))
return EC;
void **Ptr = reinterpret_cast<void**>(PtrsBlock.base());
for (unsigned I = 0; I < NumStubs; ++I)
Ptr[I] = InitialPtrVal;
StubsInfo.NumStubs = NumStubs;
StubsInfo.StubsMem = std::move(StubsMem);
return std::error_code();
}
} }