| //===- subzero/src/IceTargetLoweringX8632.cpp - x86-32 lowering -----------===// |
| // |
| // The Subzero Code Generator |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| /// |
| /// \file |
| /// \brief Implements the TargetLoweringX8632 class, which consists almost |
| /// entirely of the lowering sequence for each high-level instruction. |
| /// |
| //===----------------------------------------------------------------------===// |
| |
| #include "IceTargetLoweringX8632.h" |
| |
| #include "IceTargetLoweringX8632Traits.h" |
| |
| #if defined(SUBZERO_USE_MICROSOFT_ABI) |
| extern "C" void _chkstk(); |
| #endif |
| |
| namespace X8632 { |
| std::unique_ptr<::Ice::TargetLowering> createTargetLowering(::Ice::Cfg *Func) { |
| return ::Ice::X8632::TargetX8632::create(Func); |
| } |
| |
| std::unique_ptr<::Ice::TargetDataLowering> |
| createTargetDataLowering(::Ice::GlobalContext *Ctx) { |
| return ::Ice::X8632::TargetDataX86<::Ice::X8632::TargetX8632Traits>::create( |
| Ctx); |
| } |
| |
| std::unique_ptr<::Ice::TargetHeaderLowering> |
| createTargetHeaderLowering(::Ice::GlobalContext *Ctx) { |
| return ::Ice::X8632::TargetHeaderX86::create(Ctx); |
| } |
| |
| void staticInit(::Ice::GlobalContext *Ctx) { |
| ::Ice::X8632::TargetX8632::staticInit(Ctx); |
| if (Ice::getFlags().getUseNonsfi()) { |
| // In nonsfi, we need to reference the _GLOBAL_OFFSET_TABLE_ for accessing |
| // globals. The GOT is an external symbol (i.e., it is not defined in the |
| // pexe) so we need to register it as such so that ELF emission won't barf |
| // on an "unknown" symbol. The GOT is added to the External symbols list |
| // here because staticInit() is invoked in a single-thread context. |
| Ctx->getConstantExternSym(Ctx->getGlobalString(::Ice::GlobalOffsetTable)); |
| } |
| } |
| |
| bool shouldBePooled(const class ::Ice::Constant *C) { |
| return ::Ice::X8632::TargetX8632::shouldBePooled(C); |
| } |
| |
| ::Ice::Type getPointerType() { |
| return ::Ice::X8632::TargetX8632::getPointerType(); |
| } |
| |
| } // end of namespace X8632 |
| |
| namespace Ice { |
| namespace X8632 { |
| |
| //------------------------------------------------------------------------------ |
| // ______ ______ ______ __ ______ ______ |
| // /\__ _\ /\ == \ /\ __ \ /\ \ /\__ _\ /\ ___\ |
| // \/_/\ \/ \ \ __< \ \ __ \ \ \ \ \/_/\ \/ \ \___ \ |
| // \ \_\ \ \_\ \_\ \ \_\ \_\ \ \_\ \ \_\ \/\_____\ |
| // \/_/ \/_/ /_/ \/_/\/_/ \/_/ \/_/ \/_____/ |
| // |
| //------------------------------------------------------------------------------ |
| const TargetX8632Traits::TableFcmpType TargetX8632Traits::TableFcmp[] = { |
| #define X(val, dflt, swapS, C1, C2, swapV, pred) \ |
| {dflt, \ |
| swapS, \ |
| X8632::Traits::Cond::C1, \ |
| X8632::Traits::Cond::C2, \ |
| swapV, \ |
| X8632::Traits::Cond::pred}, |
| FCMPX8632_TABLE |
| #undef X |
| }; |
| |
| const size_t TargetX8632Traits::TableFcmpSize = llvm::array_lengthof(TableFcmp); |
| |
| const TargetX8632Traits::TableIcmp32Type TargetX8632Traits::TableIcmp32[] = { |
| #define X(val, C_32, C1_64, C2_64, C3_64) {X8632::Traits::Cond::C_32}, |
| ICMPX8632_TABLE |
| #undef X |
| }; |
| |
| const size_t TargetX8632Traits::TableIcmp32Size = |
| llvm::array_lengthof(TableIcmp32); |
| |
| const TargetX8632Traits::TableIcmp64Type TargetX8632Traits::TableIcmp64[] = { |
| #define X(val, C_32, C1_64, C2_64, C3_64) \ |
| {X8632::Traits::Cond::C1_64, X8632::Traits::Cond::C2_64, \ |
| X8632::Traits::Cond::C3_64}, |
| ICMPX8632_TABLE |
| #undef X |
| }; |
| |
| const size_t TargetX8632Traits::TableIcmp64Size = |
| llvm::array_lengthof(TableIcmp64); |
| |
| const TargetX8632Traits::TableTypeX8632AttributesType |
| TargetX8632Traits::TableTypeX8632Attributes[] = { |
| #define X(tag, elty, cvt, sdss, pdps, spsd, int_, unpack, pack, width, fld) \ |
| {IceType_##elty}, |
| ICETYPEX8632_TABLE |
| #undef X |
| }; |
| |
| const size_t TargetX8632Traits::TableTypeX8632AttributesSize = |
| llvm::array_lengthof(TableTypeX8632Attributes); |
| |
| #if defined(SUBZERO_USE_MICROSOFT_ABI) |
| // Windows 32-bit only guarantees 4 byte stack alignment |
| const uint32_t TargetX8632Traits::X86_STACK_ALIGNMENT_BYTES = 4; |
| #else |
| const uint32_t TargetX8632Traits::X86_STACK_ALIGNMENT_BYTES = 16; |
| #endif |
| const char *TargetX8632Traits::TargetName = "X8632"; |
| |
| template <> |
| std::array<SmallBitVector, RCX86_NUM> |
| TargetX86Base<X8632::Traits>::TypeToRegisterSet = {{}}; |
| |
| template <> |
| std::array<SmallBitVector, RCX86_NUM> |
| TargetX86Base<X8632::Traits>::TypeToRegisterSetUnfiltered = {{}}; |
| |
| template <> |
| std::array<SmallBitVector, |
| TargetX86Base<X8632::Traits>::Traits::RegisterSet::Reg_NUM> |
| TargetX86Base<X8632::Traits>::RegisterAliases = {{}}; |
| |
| template <> |
| FixupKind TargetX86Base<X8632::Traits>::PcRelFixup = |
| TargetX86Base<X8632::Traits>::Traits::FK_PcRel; |
| |
| template <> |
| FixupKind TargetX86Base<X8632::Traits>::AbsFixup = |
| TargetX86Base<X8632::Traits>::Traits::FK_Abs; |
| |
| //------------------------------------------------------------------------------ |
| // __ ______ __ __ ______ ______ __ __ __ ______ |
| // /\ \ /\ __ \/\ \ _ \ \/\ ___\/\ == \/\ \/\ "-.\ \/\ ___\ |
| // \ \ \___\ \ \/\ \ \ \/ ".\ \ \ __\\ \ __<\ \ \ \ \-. \ \ \__ \ |
| // \ \_____\ \_____\ \__/".~\_\ \_____\ \_\ \_\ \_\ \_\\"\_\ \_____\ |
| // \/_____/\/_____/\/_/ \/_/\/_____/\/_/ /_/\/_/\/_/ \/_/\/_____/ |
| // |
| //------------------------------------------------------------------------------ |
| void TargetX8632::_add_sp(Operand *Adjustment) { |
| Variable *esp = getPhysicalRegister(Traits::RegisterSet::Reg_esp); |
| _add(esp, Adjustment); |
| } |
| |
| void TargetX8632::_mov_sp(Operand *NewValue) { |
| Variable *esp = getPhysicalRegister(Traits::RegisterSet::Reg_esp); |
| _redefined(_mov(esp, NewValue)); |
| } |
| |
| Traits::X86OperandMem *TargetX8632::_sandbox_mem_reference(X86OperandMem *Mem) { |
| switch (SandboxingType) { |
| case ST_None: |
| case ST_NaCl: |
| return Mem; |
| case ST_Nonsfi: { |
| if (Mem->getIsRebased()) { |
| return Mem; |
| } |
| // For Non-SFI mode, if the Offset field is a ConstantRelocatable, we |
| // replace either Base or Index with a legalized RebasePtr. At emission |
| // time, the ConstantRelocatable will be emitted with the @GOTOFF |
| // relocation. |
| if (llvm::dyn_cast_or_null<ConstantRelocatable>(Mem->getOffset()) == |
| nullptr) { |
| return Mem; |
| } |
| Variable *T; |
| uint16_t Shift = 0; |
| if (Mem->getIndex() == nullptr) { |
| T = Mem->getBase(); |
| } else if (Mem->getBase() == nullptr) { |
| T = Mem->getIndex(); |
| Shift = Mem->getShift(); |
| } else { |
| llvm::report_fatal_error( |
| "Either Base or Index must be unused in Non-SFI mode"); |
| } |
| Variable *RebasePtrR = legalizeToReg(RebasePtr); |
| static constexpr bool IsRebased = true; |
| return Traits::X86OperandMem::create( |
| Func, Mem->getType(), RebasePtrR, Mem->getOffset(), T, Shift, |
| Traits::X86OperandMem::DefaultSegment, IsRebased); |
| } |
| } |
| llvm::report_fatal_error("Unhandled sandboxing type: " + |
| std::to_string(SandboxingType)); |
| } |
| |
| void TargetX8632::_sub_sp(Operand *Adjustment) { |
| Variable *esp = getPhysicalRegister(Traits::RegisterSet::Reg_esp); |
| _sub(esp, Adjustment); |
| // Add a fake use of the stack pointer, to prevent the stack pointer adustment |
| // from being dead-code eliminated in a function that doesn't return. |
| Context.insert<InstFakeUse>(esp); |
| } |
| |
| void TargetX8632::_link_bp() { |
| Variable *ebp = getPhysicalRegister(Traits::RegisterSet::Reg_ebp); |
| Variable *esp = getPhysicalRegister(Traits::RegisterSet::Reg_esp); |
| _push(ebp); |
| _mov(ebp, esp); |
| // Keep ebp live for late-stage liveness analysis (e.g. asm-verbose mode). |
| Context.insert<InstFakeUse>(ebp); |
| } |
| |
| void TargetX8632::_unlink_bp() { |
| Variable *esp = getPhysicalRegister(Traits::RegisterSet::Reg_esp); |
| Variable *ebp = getPhysicalRegister(Traits::RegisterSet::Reg_ebp); |
| // For late-stage liveness analysis (e.g. asm-verbose mode), adding a fake |
| // use of esp before the assignment of esp=ebp keeps previous esp |
| // adjustments from being dead-code eliminated. |
| Context.insert<InstFakeUse>(esp); |
| _mov(esp, ebp); |
| _pop(ebp); |
| } |
| |
| void TargetX8632::_push_reg(RegNumT RegNum) { |
| _push(getPhysicalRegister(RegNum, Traits::WordType)); |
| } |
| |
| void TargetX8632::_pop_reg(RegNumT RegNum) { |
| _pop(getPhysicalRegister(RegNum, Traits::WordType)); |
| } |
| |
| void TargetX8632::emitGetIP(CfgNode *Node) { |
| // If there is a non-deleted InstX86GetIP instruction, we need to move it to |
| // the point after the stack frame has stabilized but before |
| // register-allocated in-args are copied into their home registers. It would |
| // be slightly faster to search for the GetIP instruction before other prolog |
| // instructions are inserted, but it's more clear to do the whole |
| // transformation in a single place. |
| Traits::Insts::GetIP *GetIPInst = nullptr; |
| if (getFlags().getUseNonsfi()) { |
| for (Inst &Instr : Node->getInsts()) { |
| if (auto *GetIP = llvm::dyn_cast<Traits::Insts::GetIP>(&Instr)) { |
| if (!Instr.isDeleted()) |
| GetIPInst = GetIP; |
| break; |
| } |
| } |
| } |
| // Delete any existing InstX86GetIP instruction and reinsert it here. Also, |
| // insert the call to the helper function and the spill to the stack, to |
| // simplify emission. |
| if (GetIPInst) { |
| GetIPInst->setDeleted(); |
| Variable *Dest = GetIPInst->getDest(); |
| Variable *CallDest = |
| Dest->hasReg() ? Dest |
| : getPhysicalRegister(Traits::RegisterSet::Reg_eax); |
| auto *BeforeAddReloc = RelocOffset::create(Ctx); |
| BeforeAddReloc->setSubtract(true); |
| auto *BeforeAdd = InstX86Label::create(Func, this); |
| BeforeAdd->setRelocOffset(BeforeAddReloc); |
| |
| auto *AfterAddReloc = RelocOffset::create(Ctx); |
| auto *AfterAdd = InstX86Label::create(Func, this); |
| AfterAdd->setRelocOffset(AfterAddReloc); |
| |
| const RelocOffsetT ImmSize = -typeWidthInBytes(IceType_i32); |
| |
| auto *GotFromPc = |
| llvm::cast<ConstantRelocatable>(Ctx->getConstantSymWithEmitString( |
| ImmSize, {AfterAddReloc, BeforeAddReloc}, |
| Ctx->getGlobalString(GlobalOffsetTable), GlobalOffsetTable)); |
| |
| // Insert a new version of InstX86GetIP. |
| Context.insert<Traits::Insts::GetIP>(CallDest); |
| |
| Context.insert(BeforeAdd); |
| _add(CallDest, GotFromPc); |
| Context.insert(AfterAdd); |
| |
| // Spill the register to its home stack location if necessary. |
| if (Dest != CallDest) { |
| _mov(Dest, CallDest); |
| } |
| } |
| } |
| |
| void TargetX8632::lowerIndirectJump(Variable *JumpTarget) { |
| AutoBundle _(this); |
| |
| if (NeedSandboxing) { |
| const SizeT BundleSize = |
| 1 << Func->getAssembler<>()->getBundleAlignLog2Bytes(); |
| _and(JumpTarget, Ctx->getConstantInt32(~(BundleSize - 1))); |
| } |
| |
| _jmp(JumpTarget); |
| } |
| |
| void TargetX8632::initRebasePtr() { |
| if (SandboxingType == ST_Nonsfi) { |
| RebasePtr = Func->makeVariable(IceType_i32); |
| } |
| } |
| |
| void TargetX8632::initSandbox() { |
| if (SandboxingType != ST_Nonsfi) { |
| return; |
| } |
| // Insert the RebasePtr assignment as the very first lowered instruction. |
| // Later, it will be moved into the right place - after the stack frame is set |
| // up but before in-args are copied into registers. |
| Context.init(Func->getEntryNode()); |
| Context.setInsertPoint(Context.getCur()); |
| Context.insert<Traits::Insts::GetIP>(RebasePtr); |
| } |
| |
| bool TargetX8632::legalizeOptAddrForSandbox(OptAddr *Addr) { |
| if (Addr->Relocatable == nullptr || SandboxingType != ST_Nonsfi) { |
| return true; |
| } |
| |
| if (Addr->Base == RebasePtr || Addr->Index == RebasePtr) { |
| return true; |
| } |
| |
| if (Addr->Base == nullptr) { |
| Addr->Base = RebasePtr; |
| return true; |
| } |
| |
| if (Addr->Index == nullptr) { |
| Addr->Index = RebasePtr; |
| Addr->Shift = 0; |
| return true; |
| } |
| |
| return false; |
| } |
| |
| Inst *TargetX8632::emitCallToTarget(Operand *CallTarget, Variable *ReturnReg, |
| size_t NumVariadicFpArgs) { |
| (void)NumVariadicFpArgs; |
| // Note that NumVariadicFpArgs is only used for System V x86-64 variadic |
| // calls, because floating point arguments are passed via vector registers, |
| // whereas for x86-32, all args are passed via the stack. |
| |
| std::unique_ptr<AutoBundle> Bundle; |
| if (NeedSandboxing) { |
| if (llvm::isa<Constant>(CallTarget)) { |
| Bundle = makeUnique<AutoBundle>(this, InstBundleLock::Opt_AlignToEnd); |
| } else { |
| Variable *CallTargetVar = nullptr; |
| _mov(CallTargetVar, CallTarget); |
| Bundle = makeUnique<AutoBundle>(this, InstBundleLock::Opt_AlignToEnd); |
| const SizeT BundleSize = |
| 1 << Func->getAssembler<>()->getBundleAlignLog2Bytes(); |
| _and(CallTargetVar, Ctx->getConstantInt32(~(BundleSize - 1))); |
| CallTarget = CallTargetVar; |
| } |
| } |
| return Context.insert<Traits::Insts::Call>(ReturnReg, CallTarget); |
| } |
| |
| Variable *TargetX8632::moveReturnValueToRegister(Operand *Value, |
| Type ReturnType) { |
| if (isVectorType(ReturnType)) { |
| return legalizeToReg(Value, Traits::RegisterSet::Reg_xmm0); |
| } else if (isScalarFloatingType(ReturnType)) { |
| _fld(Value); |
| return nullptr; |
| } else { |
| assert(ReturnType == IceType_i32 || ReturnType == IceType_i64); |
| if (ReturnType == IceType_i64) { |
| Variable *eax = |
| legalizeToReg(loOperand(Value), Traits::RegisterSet::Reg_eax); |
| Variable *edx = |
| legalizeToReg(hiOperand(Value), Traits::RegisterSet::Reg_edx); |
| Context.insert<InstFakeUse>(edx); |
| return eax; |
| } else { |
| Variable *Reg = nullptr; |
| _mov(Reg, Value, Traits::RegisterSet::Reg_eax); |
| return Reg; |
| } |
| } |
| } |
| |
| void TargetX8632::emitSandboxedReturn() { |
| // Change the original ret instruction into a sandboxed return sequence. |
| // t:ecx = pop |
| // bundle_lock |
| // and t, ~31 |
| // jmp *t |
| // bundle_unlock |
| // FakeUse <original_ret_operand> |
| Variable *T_ecx = makeReg(IceType_i32, Traits::RegisterSet::Reg_ecx); |
| _pop(T_ecx); |
| lowerIndirectJump(T_ecx); |
| } |
| |
| void TargetX8632::emitStackProbe(size_t StackSizeBytes) { |
| #if defined(SUBZERO_USE_MICROSOFT_ABI) |
| if (StackSizeBytes >= 4096) { |
| // _chkstk on Win32 is actually __alloca_probe, which adjusts ESP by the |
| // stack amount specified in EAX, so we save ESP in ECX, and restore them |
| // both after the call. |
| |
| Variable *EAX = makeReg(IceType_i32, Traits::RegisterSet::Reg_eax); |
| Variable *ESP = makeReg(IceType_i32, Traits::RegisterSet::Reg_esp); |
| Variable *ECX = makeReg(IceType_i32, Traits::RegisterSet::Reg_ecx); |
| |
| _push_reg(ECX->getRegNum()); |
| _mov(ECX, ESP); |
| |
| _mov(EAX, Ctx->getConstantInt32(StackSizeBytes)); |
| |
| auto *CallTarget = |
| Ctx->getConstantInt32(reinterpret_cast<int32_t>(&_chkstk)); |
| emitCallToTarget(CallTarget, nullptr); |
| |
| _mov(ESP, ECX); |
| _pop_reg(ECX->getRegNum()); |
| } |
| #endif |
| } |
| |
| // In some cases, there are x-macros tables for both high-level and low-level |
| // instructions/operands that use the same enum key value. The tables are kept |
| // separate to maintain a proper separation between abstraction layers. There |
| // is a risk that the tables could get out of sync if enum values are reordered |
| // or if entries are added or deleted. The following dummy namespaces use |
| // static_asserts to ensure everything is kept in sync. |
| |
| namespace { |
| // Validate the enum values in FCMPX8632_TABLE. |
| namespace dummy1 { |
| // Define a temporary set of enum values based on low-level table entries. |
| enum _tmp_enum { |
| #define X(val, dflt, swapS, C1, C2, swapV, pred) _tmp_##val, |
| FCMPX8632_TABLE |
| #undef X |
| _num |
| }; |
| // Define a set of constants based on high-level table entries. |
| #define X(tag, str) static const int _table1_##tag = InstFcmp::tag; |
| ICEINSTFCMP_TABLE |
| #undef X |
| // Define a set of constants based on low-level table entries, and ensure the |
| // table entry keys are consistent. |
| #define X(val, dflt, swapS, C1, C2, swapV, pred) \ |
| static const int _table2_##val = _tmp_##val; \ |
| static_assert( \ |
| _table1_##val == _table2_##val, \ |
| "Inconsistency between FCMPX8632_TABLE and ICEINSTFCMP_TABLE"); |
| FCMPX8632_TABLE |
| #undef X |
| // Repeat the static asserts with respect to the high-level table entries in |
| // case the high-level table has extra entries. |
| #define X(tag, str) \ |
| static_assert( \ |
| _table1_##tag == _table2_##tag, \ |
| "Inconsistency between FCMPX8632_TABLE and ICEINSTFCMP_TABLE"); |
| ICEINSTFCMP_TABLE |
| #undef X |
| } // end of namespace dummy1 |
| |
| // Validate the enum values in ICMPX8632_TABLE. |
| namespace dummy2 { |
| // Define a temporary set of enum values based on low-level table entries. |
| enum _tmp_enum { |
| #define X(val, C_32, C1_64, C2_64, C3_64) _tmp_##val, |
| ICMPX8632_TABLE |
| #undef X |
| _num |
| }; |
| // Define a set of constants based on high-level table entries. |
| #define X(tag, reverse, str) static const int _table1_##tag = InstIcmp::tag; |
| ICEINSTICMP_TABLE |
| #undef X |
| // Define a set of constants based on low-level table entries, and ensure the |
| // table entry keys are consistent. |
| #define X(val, C_32, C1_64, C2_64, C3_64) \ |
| static const int _table2_##val = _tmp_##val; \ |
| static_assert( \ |
| _table1_##val == _table2_##val, \ |
| "Inconsistency between ICMPX8632_TABLE and ICEINSTICMP_TABLE"); |
| ICMPX8632_TABLE |
| #undef X |
| // Repeat the static asserts with respect to the high-level table entries in |
| // case the high-level table has extra entries. |
| #define X(tag, reverse, str) \ |
| static_assert( \ |
| _table1_##tag == _table2_##tag, \ |
| "Inconsistency between ICMPX8632_TABLE and ICEINSTICMP_TABLE"); |
| ICEINSTICMP_TABLE |
| #undef X |
| } // end of namespace dummy2 |
| |
| // Validate the enum values in ICETYPEX8632_TABLE. |
| namespace dummy3 { |
| // Define a temporary set of enum values based on low-level table entries. |
| enum _tmp_enum { |
| #define X(tag, elty, cvt, sdss, pdps, spsd, int_, unpack, pack, width, fld) \ |
| _tmp_##tag, |
| ICETYPEX8632_TABLE |
| #undef X |
| _num |
| }; |
| // Define a set of constants based on high-level table entries. |
| #define X(tag, sizeLog2, align, elts, elty, str, rcstr) \ |
| static const int _table1_##tag = IceType_##tag; |
| ICETYPE_TABLE |
| #undef X |
| // Define a set of constants based on low-level table entries, and ensure the |
| // table entry keys are consistent. |
| #define X(tag, elty, cvt, sdss, pdps, spsd, int_, unpack, pack, width, fld) \ |
| static const int _table2_##tag = _tmp_##tag; \ |
| static_assert(_table1_##tag == _table2_##tag, \ |
| "Inconsistency between ICETYPEX8632_TABLE and ICETYPE_TABLE"); |
| ICETYPEX8632_TABLE |
| #undef X |
| // Repeat the static asserts with respect to the high-level table entries in |
| // case the high-level table has extra entries. |
| #define X(tag, sizeLog2, align, elts, elty, str, rcstr) \ |
| static_assert(_table1_##tag == _table2_##tag, \ |
| "Inconsistency between ICETYPEX8632_TABLE and ICETYPE_TABLE"); |
| ICETYPE_TABLE |
| #undef X |
| } // end of namespace dummy3 |
| } // end of anonymous namespace |
| |
| } // end of namespace X8632 |
| } // end of namespace Ice |