diff options
Diffstat (limited to 'llvm/lib/ExecutionEngine/Orc/OrcABISupport.cpp')
-rw-r--r-- | llvm/lib/ExecutionEngine/Orc/OrcABISupport.cpp | 542 |
1 files changed, 542 insertions, 0 deletions
diff --git a/llvm/lib/ExecutionEngine/Orc/OrcABISupport.cpp b/llvm/lib/ExecutionEngine/Orc/OrcABISupport.cpp new file mode 100644 index 00000000000..9869b6c7050 --- /dev/null +++ b/llvm/lib/ExecutionEngine/Orc/OrcABISupport.cpp @@ -0,0 +1,542 @@ +//===------------- OrcABISupport.cpp - ABI specific support code ----------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#include "llvm/ExecutionEngine/Orc/OrcABISupport.h" +#include "llvm/ADT/Triple.h" +#include "llvm/Support/Process.h" + +namespace llvm { +namespace orc { + +void OrcAArch64::writeResolverCode(uint8_t *ResolverMem, JITReentryFn ReentryFn, + void *CallbackMgr) { + + const uint32_t ResolverCode[] = { + // resolver_entry: + 0xa9bf47fd, // 0x000: stp x29, x17, [sp, #-16]! + 0x910003fd, // 0x004: mov x29, sp + 0xa9bf73fb, // 0x008: stp x27, x28, [sp, #-16]! + 0xa9bf6bf9, // 0x00c: stp x25, x26, [sp, #-16]! + 0xa9bf63f7, // 0x010: stp x23, x24, [sp, #-16]! + 0xa9bf5bf5, // 0x014: stp x21, x22, [sp, #-16]! + 0xa9bf53f3, // 0x018: stp x19, x20, [sp, #-16]! + 0xa9bf3fee, // 0x01c: stp x14, x15, [sp, #-16]! + 0xa9bf37ec, // 0x020: stp x12, x13, [sp, #-16]! + 0xa9bf2fea, // 0x024: stp x10, x11, [sp, #-16]! + 0xa9bf27e8, // 0x028: stp x8, x9, [sp, #-16]! + 0xa9bf1fe6, // 0x02c: stp x6, x7, [sp, #-16]! + 0xa9bf17e4, // 0x030: stp x4, x5, [sp, #-16]! + 0xa9bf0fe2, // 0x034: stp x2, x3, [sp, #-16]! + 0xa9bf07e0, // 0x038: stp x0, x1, [sp, #-16]! + 0xadbf7ffe, // 0x03c: stp q30, q31, [sp, #-32]! + 0xadbf77fc, // 0x040: stp q28, q29, [sp, #-32]! + 0xadbf6ffa, // 0x044: stp q26, q27, [sp, #-32]! + 0xadbf67f8, // 0x048: stp q24, q25, [sp, #-32]! + 0xadbf5ff6, // 0x04c: stp q22, q23, [sp, #-32]! + 0xadbf57f4, // 0x050: stp q20, q21, [sp, #-32]! + 0xadbf4ff2, // 0x054: stp q18, q19, [sp, #-32]! + 0xadbf47f0, // 0x058: stp q16, q17, [sp, #-32]! + 0xadbf3fee, // 0x05c: stp q14, q15, [sp, #-32]! + 0xadbf37ec, // 0x060: stp q12, q13, [sp, #-32]! + 0xadbf2fea, // 0x064: stp q10, q11, [sp, #-32]! + 0xadbf27e8, // 0x068: stp q8, q9, [sp, #-32]! + 0xadbf1fe6, // 0x06c: stp q6, q7, [sp, #-32]! + 0xadbf17e4, // 0x070: stp q4, q5, [sp, #-32]! + 0xadbf0fe2, // 0x074: stp q2, q3, [sp, #-32]! + 0xadbf07e0, // 0x078: stp q0, q1, [sp, #-32]! + 0x580004e0, // 0x07c: ldr x0, Lcallbackmgr + 0xaa1e03e1, // 0x080: mov x1, x30 + 0xd1003021, // 0x084: sub x1, x1, #12 + 0x58000442, // 0x088: ldr x2, Lreentry_fn_ptr + 0xd63f0040, // 0x08c: blr x2 + 0xaa0003f1, // 0x090: mov x17, x0 + 0xacc107e0, // 0x094: ldp q0, q1, [sp], #32 + 0xacc10fe2, // 0x098: ldp q2, q3, [sp], #32 + 0xacc117e4, // 0x09c: ldp q4, q5, [sp], #32 + 0xacc11fe6, // 0x0a0: ldp q6, q7, [sp], #32 + 0xacc127e8, // 0x0a4: ldp q8, q9, [sp], #32 + 0xacc12fea, // 0x0a8: ldp q10, q11, [sp], #32 + 0xacc137ec, // 0x0ac: ldp q12, q13, [sp], #32 + 0xacc13fee, // 0x0b0: ldp q14, q15, [sp], #32 + 0xacc147f0, // 0x0b4: ldp q16, q17, [sp], #32 + 0xacc14ff2, // 0x0b8: ldp q18, q19, [sp], #32 + 0xacc157f4, // 0x0bc: ldp q20, q21, [sp], #32 + 0xacc15ff6, // 0x0c0: ldp q22, q23, [sp], #32 + 0xacc167f8, // 0x0c4: ldp q24, q25, [sp], #32 + 0xacc16ffa, // 0x0c8: ldp q26, q27, [sp], #32 + 0xacc177fc, // 0x0cc: ldp q28, q29, [sp], #32 + 0xacc17ffe, // 0x0d0: ldp q30, q31, [sp], #32 + 0xa8c107e0, // 0x0d4: ldp x0, x1, [sp], #16 + 0xa8c10fe2, // 0x0d8: ldp x2, x3, [sp], #16 + 0xa8c117e4, // 0x0dc: ldp x4, x5, [sp], #16 + 0xa8c11fe6, // 0x0e0: ldp x6, x7, [sp], #16 + 0xa8c127e8, // 0x0e4: ldp x8, x9, [sp], #16 + 0xa8c12fea, // 0x0e8: ldp x10, x11, [sp], #16 + 0xa8c137ec, // 0x0ec: ldp x12, x13, [sp], #16 + 0xa8c13fee, // 0x0f0: ldp x14, x15, [sp], #16 + 0xa8c153f3, // 0x0f4: ldp x19, x20, [sp], #16 + 0xa8c15bf5, // 0x0f8: ldp x21, x22, [sp], #16 + 0xa8c163f7, // 0x0fc: ldp x23, x24, [sp], #16 + 0xa8c16bf9, // 0x100: ldp x25, x26, [sp], #16 + 0xa8c173fb, // 0x104: ldp x27, x28, [sp], #16 + 0xa8c17bfd, // 0x108: ldp x29, x30, [sp], #16 + 0xd65f0220, // 0x10c: ret x17 + 0x01234567, // 0x110: Lreentry_fn_ptr: + 0xdeadbeef, // 0x114: .quad 0 + 0x98765432, // 0x118: Lcallbackmgr: + 0xcafef00d // 0x11c: .quad 0 + }; + + const unsigned ReentryFnAddrOffset = 0x110; + const unsigned CallbackMgrAddrOffset = 0x118; + + memcpy(ResolverMem, ResolverCode, sizeof(ResolverCode)); + memcpy(ResolverMem + ReentryFnAddrOffset, &ReentryFn, sizeof(ReentryFn)); + memcpy(ResolverMem + CallbackMgrAddrOffset, &CallbackMgr, + sizeof(CallbackMgr)); +} + +void OrcAArch64::writeTrampolines(uint8_t *TrampolineMem, void *ResolverAddr, + unsigned NumTrampolines) { + + unsigned OffsetToPtr = alignTo(NumTrampolines * TrampolineSize, 8); + + memcpy(TrampolineMem + OffsetToPtr, &ResolverAddr, sizeof(void *)); + + // OffsetToPtr is actually the offset from the PC for the 2nd instruction, so + // subtract 32-bits. + OffsetToPtr -= 4; + + uint32_t *Trampolines = reinterpret_cast<uint32_t *>(TrampolineMem); + + for (unsigned I = 0; I < NumTrampolines; ++I, OffsetToPtr -= TrampolineSize) { + Trampolines[3 * I + 0] = 0xaa1e03f1; // mov x17, x30 + Trampolines[3 * I + 1] = 0x58000010 | (OffsetToPtr << 3); // mov x16, Lptr + Trampolines[3 * I + 2] = 0xd63f0200; // blr x16 + } + +} + +Error OrcAArch64::emitIndirectStubsBlock(IndirectStubsInfo &StubsInfo, + unsigned MinStubs, + void *InitialPtrVal) { + // Stub format is: + // + // .section __orc_stubs + // stub1: + // ldr x0, ptr1 ; PC-rel load of ptr1 + // br x0 ; Jump to resolver + // stub2: + // ldr x0, ptr2 ; PC-rel load of ptr2 + // br x0 ; Jump to resolver + // + // ... + // + // .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 errorCodeToError(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) + << 3; + + for (unsigned I = 0; I < NumStubs; ++I) + Stub[I] = 0xd61f020058000010 | PtrOffsetField; + + if (auto EC = sys::Memory::protectMappedMemory( + StubsBlock, sys::Memory::MF_READ | sys::Memory::MF_EXEC)) + return errorCodeToError(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 = IndirectStubsInfo(NumStubs, std::move(StubsMem)); + + return Error::success(); +} + +void OrcX86_64_Base::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); +} + +Error OrcX86_64_Base::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 errorCodeToError(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 errorCodeToError(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 = IndirectStubsInfo(NumStubs, std::move(StubsMem)); + + return Error::success(); +} + +void OrcX86_64_SysV::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 0x208, %rsp + 0x48, 0x0f, 0xae, 0x04, 0x24, // 0x21: fxsave64 (%rsp) + 0x48, 0xbf, // 0x26: movabsq <CBMgr>, %rdi + + // 0x28: Callback manager addr. + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + + 0x48, 0x8b, 0x75, 0x08, // 0x30: movq 8(%rbp), %rsi + 0x48, 0x83, 0xee, 0x06, // 0x34: subq $6, %rsi + 0x48, 0xb8, // 0x38: movabsq <REntry>, %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 0x208, %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 + }; + + const unsigned ReentryFnAddrOffset = 0x3a; + const unsigned CallbackMgrAddrOffset = 0x28; + + memcpy(ResolverMem, ResolverCode, sizeof(ResolverCode)); + memcpy(ResolverMem + ReentryFnAddrOffset, &ReentryFn, sizeof(ReentryFn)); + memcpy(ResolverMem + CallbackMgrAddrOffset, &CallbackMgr, + sizeof(CallbackMgr)); +} + +void OrcX86_64_Win32::writeResolverCode(uint8_t *ResolverMem, + JITReentryFn ReentryFn, + void *CallbackMgr) { + + // resolverCode is similar to OrcX86_64 with differences specific to windows x64 calling convention: + // arguments go into rcx, rdx and come in reverse order, shadow space allocation on stack + 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 0x208, %rsp + 0x48, 0x0f, 0xae, 0x04, 0x24, // 0x21: fxsave64 (%rsp) + + 0x48, 0xb9, // 0x26: movabsq <CBMgr>, %rcx + // 0x28: Callback manager addr. + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + + 0x48, 0x8B, 0x55, 0x08, // 0x30: mov rdx, [rbp+0x8] + 0x48, 0x83, 0xea, 0x06, // 0x34: sub rdx, 0x6 + + 0x48, 0xb8, // 0x38: movabsq <REntry>, %rax + // 0x3a: JIT re-entry fn addr: + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + + // 0x42: sub rsp, 0x20 (Allocate shadow space) + 0x48, 0x83, 0xEC, 0x20, + 0xff, 0xd0, // 0x46: callq *%rax + + // 0x48: add rsp, 0x20 (Free shadow space) + 0x48, 0x83, 0xC4, 0x20, + + 0x48, 0x89, 0x45, 0x08, // 0x4C: movq %rax, 8(%rbp) + 0x48, 0x0f, 0xae, 0x0c, 0x24, // 0x50: fxrstor64 (%rsp) + 0x48, 0x81, 0xc4, 0x08, 0x02, 0x00, 0x00, // 0x55: addq 0x208, %rsp + 0x41, 0x5f, // 0x5C: popq %r15 + 0x41, 0x5e, // 0x5E: popq %r14 + 0x41, 0x5d, // 0x60: popq %r13 + 0x41, 0x5c, // 0x62: popq %r12 + 0x41, 0x5b, // 0x64: popq %r11 + 0x41, 0x5a, // 0x66: popq %r10 + 0x41, 0x59, // 0x68: popq %r9 + 0x41, 0x58, // 0x6a: popq %r8 + 0x5f, // 0x6c: popq %rdi + 0x5e, // 0x6d: popq %rsi + 0x5a, // 0x6e: popq %rdx + 0x59, // 0x6f: popq %rcx + 0x5b, // 0x70: popq %rbx + 0x58, // 0x71: popq %rax + 0x5d, // 0x72: popq %rbp + 0xc3, // 0x73: retq + }; + + + const unsigned ReentryFnAddrOffset = 0x3a; + const unsigned CallbackMgrAddrOffset = 0x28; + + memcpy(ResolverMem, ResolverCode, sizeof(ResolverCode)); + memcpy(ResolverMem + ReentryFnAddrOffset, &ReentryFn, sizeof(ReentryFn)); + memcpy(ResolverMem + CallbackMgrAddrOffset, &CallbackMgr, + sizeof(CallbackMgr)); +} + +void OrcI386::writeResolverCode(uint8_t *ResolverMem, JITReentryFn ReentryFn, + void *CallbackMgr) { + + const uint8_t ResolverCode[] = { + // resolver_entry: + 0x55, // 0x00: pushl %ebp + 0x89, 0xe5, // 0x01: movl %esp, %ebp + 0x54, // 0x03: pushl %esp + 0x83, 0xe4, 0xf0, // 0x04: andl $-0x10, %esp + 0x50, // 0x07: pushl %eax + 0x53, // 0x08: pushl %ebx + 0x51, // 0x09: pushl %ecx + 0x52, // 0x0a: pushl %edx + 0x56, // 0x0b: pushl %esi + 0x57, // 0x0c: pushl %edi + 0x81, 0xec, 0x18, 0x02, 0x00, 0x00, // 0x0d: subl $0x218, %esp + 0x0f, 0xae, 0x44, 0x24, 0x10, // 0x13: fxsave 0x10(%esp) + 0x8b, 0x75, 0x04, // 0x18: movl 0x4(%ebp), %esi + 0x83, 0xee, 0x05, // 0x1b: subl $0x5, %esi + 0x89, 0x74, 0x24, 0x04, // 0x1e: movl %esi, 0x4(%esp) + 0xc7, 0x04, 0x24, 0x00, 0x00, 0x00, + 0x00, // 0x22: movl <cbmgr>, (%esp) + 0xb8, 0x00, 0x00, 0x00, 0x00, // 0x29: movl <reentry>, %eax + 0xff, 0xd0, // 0x2e: calll *%eax + 0x89, 0x45, 0x04, // 0x30: movl %eax, 0x4(%ebp) + 0x0f, 0xae, 0x4c, 0x24, 0x10, // 0x33: fxrstor 0x10(%esp) + 0x81, 0xc4, 0x18, 0x02, 0x00, 0x00, // 0x38: addl $0x218, %esp + 0x5f, // 0x3e: popl %edi + 0x5e, // 0x3f: popl %esi + 0x5a, // 0x40: popl %edx + 0x59, // 0x41: popl %ecx + 0x5b, // 0x42: popl %ebx + 0x58, // 0x43: popl %eax + 0x8b, 0x65, 0xfc, // 0x44: movl -0x4(%ebp), %esp + 0x5d, // 0x48: popl %ebp + 0xc3 // 0x49: retl + }; + + const unsigned ReentryFnAddrOffset = 0x2a; + const unsigned CallbackMgrAddrOffset = 0x25; + + memcpy(ResolverMem, ResolverCode, sizeof(ResolverCode)); + memcpy(ResolverMem + ReentryFnAddrOffset, &ReentryFn, sizeof(ReentryFn)); + memcpy(ResolverMem + CallbackMgrAddrOffset, &CallbackMgr, + sizeof(CallbackMgr)); +} + +void OrcI386::writeTrampolines(uint8_t *TrampolineMem, void *ResolverAddr, + unsigned NumTrampolines) { + + uint64_t CallRelImm = 0xF1C4C400000000e8; + uint64_t Resolver = reinterpret_cast<uint64_t>(ResolverAddr); + uint64_t ResolverRel = + Resolver - reinterpret_cast<uint64_t>(TrampolineMem) - 5; + + uint64_t *Trampolines = reinterpret_cast<uint64_t *>(TrampolineMem); + for (unsigned I = 0; I < NumTrampolines; ++I, ResolverRel -= TrampolineSize) + Trampolines[I] = CallRelImm | (ResolverRel << 8); +} + +Error OrcI386::emitIndirectStubsBlock(IndirectStubsInfo &StubsInfo, + unsigned MinStubs, void *InitialPtrVal) { + // Stub format is: + // + // .section __orc_stubs + // stub1: + // jmpq *ptr1 + // .byte 0xC4 ; <- Invalid opcode padding. + // .byte 0xF1 + // stub2: + // jmpq *ptr2 + // + // ... + // + // .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 errorCodeToError(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 PtrAddr = reinterpret_cast<uint64_t>(PtrsBlock.base()); + for (unsigned I = 0; I < NumStubs; ++I, PtrAddr += 4) + Stub[I] = 0xF1C40000000025ff | (PtrAddr << 16); + + if (auto EC = sys::Memory::protectMappedMemory( + StubsBlock, sys::Memory::MF_READ | sys::Memory::MF_EXEC)) + return errorCodeToError(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 = IndirectStubsInfo(NumStubs, std::move(StubsMem)); + + return Error::success(); +} + +} // End namespace orc. +} // End namespace llvm. |