| //===-- MipsAsmPrinter.cpp - Mips LLVM assembly writer --------------------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file contains a printer that converts from our internal representation |
| // of machine-dependent LLVM code to GAS-format MIPS assembly language. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #define DEBUG_TYPE "mips-asm-printer" |
| |
| #include "Mips.h" |
| #include "MipsInstrInfo.h" |
| #include "MipsTargetMachine.h" |
| #include "MipsMachineFunction.h" |
| #include "llvm/Constants.h" |
| #include "llvm/DerivedTypes.h" |
| #include "llvm/Module.h" |
| #include "llvm/CodeGen/AsmPrinter.h" |
| #include "llvm/CodeGen/MachineFunctionPass.h" |
| #include "llvm/CodeGen/MachineConstantPool.h" |
| #include "llvm/CodeGen/MachineFrameInfo.h" |
| #include "llvm/CodeGen/MachineInstr.h" |
| #include "llvm/Target/TargetAsmInfo.h" |
| #include "llvm/Target/TargetData.h" |
| #include "llvm/Target/TargetMachine.h" |
| #include "llvm/Target/TargetOptions.h" |
| #include "llvm/Support/Mangler.h" |
| #include "llvm/ADT/Statistic.h" |
| #include "llvm/ADT/SetVector.h" |
| #include "llvm/ADT/StringExtras.h" |
| #include "llvm/Support/Debug.h" |
| #include "llvm/Support/CommandLine.h" |
| #include "llvm/Support/MathExtras.h" |
| #include <cctype> |
| |
| using namespace llvm; |
| |
| STATISTIC(EmittedInsts, "Number of machine instrs printed"); |
| |
| namespace { |
| struct VISIBILITY_HIDDEN MipsAsmPrinter : public AsmPrinter { |
| MipsAsmPrinter(std::ostream &O, MipsTargetMachine &TM, |
| const TargetAsmInfo *T): |
| AsmPrinter(O, TM, T) {} |
| |
| virtual const char *getPassName() const { |
| return "Mips Assembly Printer"; |
| } |
| |
| enum SetDirectiveFlags { |
| REORDER, // enables instruction reordering. |
| NOREORDER, // disables instruction reordering. |
| MACRO, // enables GAS macros. |
| NOMACRO // disables GAS macros. |
| }; |
| |
| void printOperand(const MachineInstr *MI, int opNum); |
| void printMemOperand(const MachineInstr *MI, int opNum, |
| const char *Modifier = 0); |
| |
| unsigned int getSavedRegsBitmask(bool isFloat, MachineFunction &MF); |
| void printHex32(unsigned int Value); |
| |
| void emitFunctionStart(MachineFunction &MF); |
| void emitFunctionEnd(MachineFunction &MF); |
| void emitFrameDirective(MachineFunction &MF); |
| void emitMaskDirective(MachineFunction &MF); |
| void emitFMaskDirective(MachineFunction &MF); |
| void emitSetDirective(SetDirectiveFlags Flag); |
| |
| bool printInstruction(const MachineInstr *MI); // autogenerated. |
| bool runOnMachineFunction(MachineFunction &F); |
| bool doInitialization(Module &M); |
| bool doFinalization(Module &M); |
| }; |
| } // end of anonymous namespace |
| |
| #include "MipsGenAsmWriter.inc" |
| |
| /// createMipsCodePrinterPass - Returns a pass that prints the MIPS |
| /// assembly code for a MachineFunction to the given output stream, |
| /// using the given target machine description. This should work |
| /// regardless of whether the function is in SSA form. |
| FunctionPass *llvm::createMipsCodePrinterPass(std::ostream &o, |
| MipsTargetMachine &tm) |
| { |
| return new MipsAsmPrinter(o, tm, tm.getTargetAsmInfo()); |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // |
| // Mips Asm Directives |
| // |
| // -- Frame directive "frame Stackpointer, Stacksize, RARegister" |
| // Describe the stack frame. |
| // |
| // -- Mask directives "(f)mask bitmask, offset" |
| // Tells the assembler which registers are saved and where. |
| // bitmask - contain a little endian bitset indicating which registers are |
| // saved on function prologue (e.g. with a 0x80000000 mask, the |
| // assembler knows the register 31 (RA) is saved at prologue. |
| // offset - the position before stack pointer subtraction indicating where |
| // the first saved register on prologue is located. (e.g. with a |
| // |
| // Consider the following function prologue: |
| // |
| // .frame $fp,48,$ra |
| // .mask 0xc0000000,-8 |
| // addiu $sp, $sp, -48 |
| // sw $ra, 40($sp) |
| // sw $fp, 36($sp) |
| // |
| // With a 0xc0000000 mask, the assembler knows the register 31 (RA) and |
| // 30 (FP) are saved at prologue. As the save order on prologue is from |
| // left to right, RA is saved first. A -8 offset means that after the |
| // stack pointer subtration, the first register in the mask (RA) will be |
| // saved at address 48-8=40. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| /// Mask directive for GPR |
| void MipsAsmPrinter:: |
| emitMaskDirective(MachineFunction &MF) |
| { |
| MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>(); |
| |
| int StackSize = MF.getFrameInfo()->getStackSize(); |
| int Offset = (!MipsFI->getTopSavedRegOffset()) ? 0 : |
| (-(StackSize-MipsFI->getTopSavedRegOffset())); |
| |
| #ifndef NDEBUG |
| DOUT << "--> emitMaskDirective" << "\n"; |
| DOUT << "StackSize : " << StackSize << "\n"; |
| DOUT << "getTopSavedReg : " << MipsFI->getTopSavedRegOffset() << "\n"; |
| DOUT << "Offset : " << Offset << "\n\n"; |
| #endif |
| |
| unsigned int Bitmask = getSavedRegsBitmask(false, MF); |
| O << "\t.mask \t"; |
| printHex32(Bitmask); |
| O << "," << Offset << "\n"; |
| } |
| |
| /// TODO: Mask Directive for Float Point |
| void MipsAsmPrinter:: |
| emitFMaskDirective(MachineFunction &MF) |
| { |
| unsigned int Bitmask = getSavedRegsBitmask(true, MF); |
| |
| O << "\t.fmask\t"; |
| printHex32(Bitmask); |
| O << ",0" << "\n"; |
| } |
| |
| /// Frame Directive |
| void MipsAsmPrinter:: |
| emitFrameDirective(MachineFunction &MF) |
| { |
| const MRegisterInfo &RI = *TM.getRegisterInfo(); |
| |
| unsigned stackReg = RI.getFrameRegister(MF); |
| unsigned returnReg = RI.getRARegister(); |
| unsigned stackSize = MF.getFrameInfo()->getStackSize(); |
| |
| |
| O << "\t.frame\t" << "$" << LowercaseString(RI.get(stackReg).Name) |
| << "," << stackSize << "," |
| << "$" << LowercaseString(RI.get(returnReg).Name) |
| << "\n"; |
| } |
| |
| /// Emit Set directives. |
| void MipsAsmPrinter:: |
| emitSetDirective(SetDirectiveFlags Flag) |
| { |
| O << "\t.set\t"; |
| switch(Flag) { |
| case REORDER: O << "reorder" << "\n"; break; |
| case NOREORDER: O << "noreorder" << "\n"; break; |
| case MACRO: O << "macro" << "\n"; break; |
| case NOMACRO: O << "nomacro" << "\n"; break; |
| default: break; |
| } |
| } |
| |
| // Create a bitmask with all callee saved registers for CPU |
| // or Float Point registers. For CPU registers consider RA, |
| // GP and FP for saving if necessary. |
| unsigned int MipsAsmPrinter:: |
| getSavedRegsBitmask(bool isFloat, MachineFunction &MF) |
| { |
| const MRegisterInfo &RI = *TM.getRegisterInfo(); |
| |
| // Float Point Registers, TODO |
| if (isFloat) |
| return 0; |
| |
| // CPU Registers |
| unsigned int Bitmask = 0; |
| |
| MachineFrameInfo *MFI = MF.getFrameInfo(); |
| const std::vector<CalleeSavedInfo> &CSI = MFI->getCalleeSavedInfo(); |
| for (unsigned i = 0, e = CSI.size(); i != e; ++i) |
| Bitmask |= (1 << MipsRegisterInfo::getRegisterNumbering(CSI[i].getReg())); |
| |
| if (RI.hasFP(MF)) |
| Bitmask |= (1 << MipsRegisterInfo:: |
| getRegisterNumbering(RI.getFrameRegister(MF))); |
| |
| if (MF.getFrameInfo()->hasCalls()) |
| Bitmask |= (1 << MipsRegisterInfo:: |
| getRegisterNumbering(RI.getRARegister())); |
| |
| return Bitmask; |
| } |
| |
| // Print a 32 bit hex number with all numbers. |
| void MipsAsmPrinter:: |
| printHex32(unsigned int Value) |
| { |
| O << "0x" << std::hex; |
| for (int i = 7; i >= 0; i--) |
| O << std::hex << ( (Value & (0xF << (i*4))) >> (i*4) ); |
| O << std::dec; |
| } |
| |
| /// Emit the directives used by GAS on the start of functions |
| void MipsAsmPrinter:: |
| emitFunctionStart(MachineFunction &MF) |
| { |
| // Print out the label for the function. |
| const Function *F = MF.getFunction(); |
| SwitchToTextSection(getSectionForFunction(*F).c_str(), F); |
| |
| // 2 bits aligned |
| EmitAlignment(2, F); |
| |
| O << "\t.globl\t" << CurrentFnName << "\n"; |
| O << "\t.ent\t" << CurrentFnName << "\n"; |
| O << "\t.type\t" << CurrentFnName << ", @function\n"; |
| O << CurrentFnName << ":\n"; |
| |
| emitFrameDirective(MF); |
| emitMaskDirective(MF); |
| emitFMaskDirective(MF); |
| |
| if (TM.getRelocationModel() == Reloc::Static) { |
| emitSetDirective(NOREORDER); |
| emitSetDirective(NOMACRO); |
| } |
| |
| O << "\n"; |
| } |
| |
| /// Emit the directives used by GAS on the end of functions |
| void MipsAsmPrinter:: |
| emitFunctionEnd(MachineFunction &MF) |
| { |
| if (TM.getRelocationModel() == Reloc::Static) { |
| emitSetDirective(MACRO); |
| emitSetDirective(REORDER); |
| } |
| |
| O << "\t.end\t" << CurrentFnName << "\n"; |
| } |
| |
| /// runOnMachineFunction - This uses the printMachineInstruction() |
| /// method to print assembly for each instruction. |
| bool MipsAsmPrinter:: |
| runOnMachineFunction(MachineFunction &MF) |
| { |
| SetupMachineFunction(MF); |
| |
| // Print out constants referenced by the function |
| EmitConstantPool(MF.getConstantPool()); |
| |
| // Print out jump tables referenced by the function |
| EmitJumpTableInfo(MF.getJumpTableInfo(), MF); |
| |
| O << "\n\n"; |
| |
| // What's my mangled name? |
| CurrentFnName = Mang->getValueName(MF.getFunction()); |
| |
| // Emit the function start directives |
| emitFunctionStart(MF); |
| |
| // Print out code for the function. |
| for (MachineFunction::const_iterator I = MF.begin(), E = MF.end(); |
| I != E; ++I) { |
| |
| // Print a label for the basic block. |
| if (I != MF.begin()) { |
| printBasicBlockLabel(I, true); |
| O << '\n'; |
| } |
| |
| for (MachineBasicBlock::const_iterator II = I->begin(), E = I->end(); |
| II != E; ++II) { |
| // Print the assembly for the instruction. |
| O << "\t"; |
| printInstruction(II); |
| ++EmittedInsts; |
| } |
| |
| // Each Basic Block is separated by a newline |
| O << '\n'; |
| } |
| |
| // Emit function end directives |
| emitFunctionEnd(MF); |
| |
| // We didn't modify anything. |
| return false; |
| } |
| |
| void MipsAsmPrinter:: |
| printOperand(const MachineInstr *MI, int opNum) |
| { |
| const MachineOperand &MO = MI->getOperand(opNum); |
| const MRegisterInfo &RI = *TM.getRegisterInfo(); |
| bool closeP = false; |
| bool isPIC = (TM.getRelocationModel() == Reloc::PIC_); |
| bool isCodeLarge = (TM.getCodeModel() == CodeModel::Large); |
| |
| // %hi and %lo used on mips gas to load global addresses on |
| // static code. %got is used to load global addresses when |
| // using PIC_. %call16 is used to load direct call targets |
| // on PIC_ and small code size. %call_lo and %call_hi load |
| // direct call targets on PIC_ and large code size. |
| if (MI->getOpcode() == Mips::LUi && !MO.isRegister() |
| && !MO.isImmediate()) { |
| if ((isPIC) && (isCodeLarge)) |
| O << "%call_hi("; |
| else |
| O << "%hi("; |
| closeP = true; |
| } else if ((MI->getOpcode() == Mips::ADDiu) && !MO.isRegister() |
| && !MO.isImmediate()) { |
| O << "%lo("; |
| closeP = true; |
| } else if ((isPIC) && (MI->getOpcode() == Mips::LW) |
| && (!MO.isRegister()) && (!MO.isImmediate())) { |
| const MachineOperand &firstMO = MI->getOperand(opNum-1); |
| const MachineOperand &lastMO = MI->getOperand(opNum+1); |
| if ((firstMO.isRegister()) && (lastMO.isRegister())) { |
| if ((firstMO.getReg() == Mips::T9) && (lastMO.getReg() == Mips::GP) |
| && (!isCodeLarge)) |
| O << "%call16("; |
| else if ((firstMO.getReg() != Mips::T9) && (lastMO.getReg() == Mips::GP)) |
| O << "%got("; |
| else if ((firstMO.getReg() == Mips::T9) && (lastMO.getReg() != Mips::GP) |
| && (isCodeLarge)) |
| O << "%call_lo("; |
| closeP = true; |
| } |
| } |
| |
| switch (MO.getType()) |
| { |
| case MachineOperand::MO_Register: |
| if (MRegisterInfo::isPhysicalRegister(MO.getReg())) |
| O << "$" << LowercaseString (RI.get(MO.getReg()).Name); |
| else |
| O << "$" << MO.getReg(); |
| break; |
| |
| case MachineOperand::MO_Immediate: |
| if ((MI->getOpcode() == Mips::SLTiu) || (MI->getOpcode() == Mips::ORi) || |
| (MI->getOpcode() == Mips::LUi) || (MI->getOpcode() == Mips::ANDi)) |
| O << (unsigned short int)MO.getImmedValue(); |
| else |
| O << (short int)MO.getImmedValue(); |
| break; |
| |
| case MachineOperand::MO_MachineBasicBlock: |
| printBasicBlockLabel(MO.getMachineBasicBlock()); |
| return; |
| |
| case MachineOperand::MO_GlobalAddress: |
| O << Mang->getValueName(MO.getGlobal()); |
| break; |
| |
| case MachineOperand::MO_ExternalSymbol: |
| O << MO.getSymbolName(); |
| break; |
| |
| case MachineOperand::MO_JumpTableIndex: |
| O << TAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber() |
| << '_' << MO.getJumpTableIndex(); |
| break; |
| |
| // FIXME: Verify correct |
| case MachineOperand::MO_ConstantPoolIndex: |
| O << TAI->getPrivateGlobalPrefix() << "CPI" |
| << getFunctionNumber() << "_" << MO.getConstantPoolIndex(); |
| break; |
| |
| default: |
| O << "<unknown operand type>"; abort (); break; |
| } |
| |
| if (closeP) O << ")"; |
| } |
| |
| void MipsAsmPrinter:: |
| printMemOperand(const MachineInstr *MI, int opNum, const char *Modifier) |
| { |
| // when using stack locations for not load/store instructions |
| // print the same way as all normal 3 operand instructions. |
| if (Modifier && !strcmp(Modifier, "stackloc")) { |
| printOperand(MI, opNum+1); |
| O << ", "; |
| printOperand(MI, opNum); |
| return; |
| } |
| |
| // Load/Store memory operands -- imm($reg) |
| // If PIC target the target is loaded as the |
| // pattern lw $25,%call16($28) |
| printOperand(MI, opNum); |
| O << "("; |
| printOperand(MI, opNum+1); |
| O << ")"; |
| } |
| |
| bool MipsAsmPrinter:: |
| doInitialization(Module &M) |
| { |
| Mang = new Mangler(M); |
| return false; // success |
| } |
| |
| bool MipsAsmPrinter:: |
| doFinalization(Module &M) |
| { |
| const TargetData *TD = TM.getTargetData(); |
| |
| // Print out module-level global variables here. |
| for (Module::const_global_iterator I = M.global_begin(), |
| E = M.global_end(); I != E; ++I) |
| |
| // External global require no code |
| if (I->hasInitializer()) { |
| |
| // Check to see if this is a special global |
| // used by LLVM, if so, emit it. |
| if (EmitSpecialLLVMGlobal(I)) |
| continue; |
| |
| O << "\n\n"; |
| std::string name = Mang->getValueName(I); |
| Constant *C = I->getInitializer(); |
| unsigned Size = TD->getABITypeSize(C->getType()); |
| unsigned Align = TD->getPreferredAlignmentLog(I); |
| |
| // Is this correct ? |
| if (C->isNullValue() && (I->hasLinkOnceLinkage() || |
| I->hasInternalLinkage() || I->hasWeakLinkage())) |
| { |
| if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it. |
| |
| if (!NoZerosInBSS && TAI->getBSSSection()) |
| SwitchToDataSection(TAI->getBSSSection(), I); |
| else |
| SwitchToDataSection(TAI->getDataSection(), I); |
| |
| if (I->hasInternalLinkage()) { |
| if (TAI->getLCOMMDirective()) |
| O << TAI->getLCOMMDirective() << name << "," << Size; |
| else |
| O << "\t.local\t" << name << "\n"; |
| } else { |
| O << TAI->getCOMMDirective() << name << "," << Size; |
| // The .comm alignment in bytes. |
| if (TAI->getCOMMDirectiveTakesAlignment()) |
| O << "," << (1 << Align); |
| } |
| |
| } else { |
| |
| switch (I->getLinkage()) |
| { |
| case GlobalValue::LinkOnceLinkage: |
| case GlobalValue::WeakLinkage: |
| // FIXME: Verify correct for weak. |
| // Nonnull linkonce -> weak |
| O << "\t.weak " << name << "\n"; |
| SwitchToDataSection("", I); |
| O << "\t.section\t\".llvm.linkonce.d." << name |
| << "\",\"aw\",@progbits\n"; |
| break; |
| case GlobalValue::AppendingLinkage: |
| // FIXME: appending linkage variables |
| // should go into a section of their name or |
| // something. For now, just emit them as external. |
| case GlobalValue::ExternalLinkage: |
| // If external or appending, declare as a global symbol |
| O << TAI->getGlobalDirective() << name << "\n"; |
| // Fall Through |
| case GlobalValue::InternalLinkage: |
| // FIXME: special handling for ".ctors" & ".dtors" sections |
| if (I->hasSection() && (I->getSection() == ".ctors" || |
| I->getSection() == ".dtors")) { |
| std::string SectionName = ".section " + I->getSection(); |
| SectionName += ",\"aw\",%progbits"; |
| SwitchToDataSection(SectionName.c_str()); |
| } else { |
| if (C->isNullValue() && !NoZerosInBSS && TAI->getBSSSection()) |
| SwitchToDataSection(TAI->getBSSSection(), I); |
| else if (!I->isConstant()) |
| SwitchToDataSection(TAI->getDataSection(), I); |
| else { |
| // Read-only data. |
| if (TAI->getReadOnlySection()) |
| SwitchToDataSection(TAI->getReadOnlySection(), I); |
| else |
| SwitchToDataSection(TAI->getDataSection(), I); |
| } |
| } |
| break; |
| case GlobalValue::GhostLinkage: |
| cerr << "Should not have any unmaterialized functions!\n"; |
| abort(); |
| case GlobalValue::DLLImportLinkage: |
| cerr << "DLLImport linkage is not supported by this target!\n"; |
| abort(); |
| case GlobalValue::DLLExportLinkage: |
| cerr << "DLLExport linkage is not supported by this target!\n"; |
| abort(); |
| default: |
| assert(0 && "Unknown linkage type!"); |
| } |
| |
| O << "\t.align " << Align << "\n"; |
| O << "\t.type " << name << ",@object\n"; |
| O << "\t.size " << name << "," << Size << "\n"; |
| O << name << ":\n"; |
| EmitGlobalConstant(C); |
| } |
| } |
| |
| return AsmPrinter::doFinalization(M); |
| } |