//===------- OrcTargetSupport.cpp - Target support utilities for Orc ------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#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[] = {
// resolver_entry:
0x55, // 0x00: pushq %rbp
0x48, 0x89, 0xe5, // 0x01: movq %rsp, %rbp
0x50, // 0x04: pushq %rax
0x53, // 0x05: pushq %rbx
0x51, // 0x06: pushq %rcx
0x52, // 0x07: pushq %rdx
0x56, // 0x08: pushq %rsi
0x57, // 0x09: pushq %rdi
0x41, 0x50, // 0x0a: pushq %r8
0x41, 0x51, // 0x0c: pushq %r9
0x41, 0x52, // 0x0e: pushq %r10
0x41, 0x53, // 0x10: pushq %r11
0x41, 0x54, // 0x12: pushq %r12
0x41, 0x55, // 0x14: pushq %r13
0x41, 0x56, // 0x16: pushq %r14
0x41, 0x57, // 0x18: pushq %r15
0x48, 0x81, 0xec, 0x08, 0x02, 0x00, 0x00, // 0x1a: subq 20, %rsp
0x48, 0x0f, 0xae, 0x04, 0x24, // 0x21: fxsave64 (%rsp)
0x48, 0x8d, 0x3d, 0x43, 0x00, 0x00, 0x00, // 0x26: leaq 67(%rip), %rdi
0x48, 0x8b, 0x3f, // 0x2d: movq (%rdi), %rdi
0x48, 0x8b, 0x75, 0x08, // 0x30: movq 8(%rbp), %rsi
0x48, 0x83, 0xee, 0x06, // 0x34: subq $6, %rsi
0x48, 0xb8, // 0x38: movabsq $0, %rax
// 0x3a: JIT re-entry fn addr:
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0xff, 0xd0, // 0x42: callq *%rax
0x48, 0x89, 0x45, 0x08, // 0x44: movq %rax, 8(%rbp)
0x48, 0x0f, 0xae, 0x0c, 0x24, // 0x48: fxrstor64 (%rsp)
0x48, 0x81, 0xc4, 0x08, 0x02, 0x00, 0x00, // 0x4d: addq 20, %rsp
0x41, 0x5f, // 0x54: popq %r15
0x41, 0x5e, // 0x56: popq %r14
0x41, 0x5d, // 0x58: popq %r13
0x41, 0x5c, // 0x5a: popq %r12
0x41, 0x5b, // 0x5c: popq %r11
0x41, 0x5a, // 0x5e: popq %r10
0x41, 0x59, // 0x60: popq %r9
0x41, 0x58, // 0x62: popq %r8
0x5f, // 0x64: popq %rdi
0x5e, // 0x65: popq %rsi
0x5a, // 0x66: popq %rdx
0x59, // 0x67: popq %rcx
0x5b, // 0x68: popq %rbx
0x58, // 0x69: popq %rax
0x5d, // 0x6a: popq %rbp
0xc3, // 0x6b: retq
0x00, 0x00, 0x00, 0x00, // 0x6c: <padding>
// 0x70: Callback mgr address.
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) {
// Stub format is:
//
// .section __orc_stubs
// stub1:
// jmpq *ptr1(%rip)
// .byte 0xC4 ; <- Invalid opcode padding.
// .byte 0xF1
// stub2:
// jmpq *ptr2(%rip)
//
// ...
//
// .section __orc_ptrs
// ptr1:
// .quad 0x0
// ptr2:
// .quad 0x0
//
// ...
const unsigned StubSize = IndirectStubsInfo::StubSize;
// Emit at least MinStubs, rounded up to fill the pages allocated.
unsigned PageSize = sys::Process::getPageSize();
unsigned NumPages = ((MinStubs * StubSize) + (PageSize - 1)) / PageSize;
unsigned NumStubs = (NumPages * PageSize) / StubSize;
// Allocate memory for stubs and pointers in one call.
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;
// Create separate MemoryBlocks representing the stubs and pointers.
sys::MemoryBlock StubsBlock(StubsMem.base(), NumPages * PageSize);
sys::MemoryBlock PtrsBlock(static_cast<char*>(StubsMem.base()) +
NumPages * PageSize,
NumPages * PageSize);
// Populate the stubs page stubs and mark it executable.
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;
// Initialize all pointers to point at FailureAddress.
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();
}
} // End namespace orc.
} // End namespace llvm.