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//===-- MipsAsmPrinter.cpp - Mips LLVM Assembly Printer -------------------===//
//
// 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.
//
//===----------------------------------------------------------------------===//
#include "InstPrinter/MipsInstPrinter.h"
#include "MCTargetDesc/MipsBaseInfo.h"
#include "MCTargetDesc/MipsMCNaCl.h"
#include "Mips.h"
#include "MipsAsmPrinter.h"
#include "MipsInstrInfo.h"
#include "MipsMCInstLower.h"
#include "MipsTargetStreamer.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/ADT/Twine.h"
#include "llvm/CodeGen/MachineConstantPool.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/CodeGen/MachineJumpTableInfo.h"
#include "llvm/CodeGen/MachineMemOperand.h"
#include "llvm/IR/BasicBlock.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/InlineAsm.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/Mangler.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCELFStreamer.h"
#include "llvm/MC/MCExpr.h"
#include "llvm/MC/MCInst.h"
#include "llvm/MC/MCSection.h"
#include "llvm/MC/MCSectionELF.h"
#include "llvm/MC/MCSymbol.h"
#include "llvm/Support/ELF.h"
#include "llvm/Support/TargetRegistry.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Target/TargetLoweringObjectFile.h"
#include "llvm/Target/TargetOptions.h"
#include <string>
using namespace llvm;
#define DEBUG_TYPE "mips-asm-printer"
MipsTargetStreamer &MipsAsmPrinter::getTargetStreamer() {
return static_cast<MipsTargetStreamer &>(*OutStreamer.getTargetStreamer());
}
bool MipsAsmPrinter::runOnMachineFunction(MachineFunction &MF) {
// Initialize TargetLoweringObjectFile.
if (Subtarget->allowMixed16_32())
const_cast<TargetLoweringObjectFile&>(getObjFileLowering())
.Initialize(OutContext, TM);
MipsFI = MF.getInfo<MipsFunctionInfo>();
if (Subtarget->inMips16Mode())
for (std::map<
const char *,
const llvm::Mips16HardFloatInfo::FuncSignature *>::const_iterator
it = MipsFI->StubsNeeded.begin();
it != MipsFI->StubsNeeded.end(); ++it) {
const char *Symbol = it->first;
const llvm::Mips16HardFloatInfo::FuncSignature *Signature = it->second;
if (StubsNeeded.find(Symbol) == StubsNeeded.end())
StubsNeeded[Symbol] = Signature;
}
MCP = MF.getConstantPool();
// In NaCl, all indirect jump targets must be aligned to bundle size.
if (Subtarget->isTargetNaCl())
NaClAlignIndirectJumpTargets(MF);
AsmPrinter::runOnMachineFunction(MF);
return true;
}
bool MipsAsmPrinter::lowerOperand(const MachineOperand &MO, MCOperand &MCOp) {
MCOp = MCInstLowering.LowerOperand(MO);
return MCOp.isValid();
}
#include "MipsGenMCPseudoLowering.inc"
void MipsAsmPrinter::EmitInstruction(const MachineInstr *MI) {
if (MI->isDebugValue()) {
SmallString<128> Str;
raw_svector_ostream OS(Str);
PrintDebugValueComment(MI, OS);
return;
}
// If we just ended a constant pool, mark it as such.
if (InConstantPool && MI->getOpcode() != Mips::CONSTPOOL_ENTRY) {
OutStreamer.EmitDataRegion(MCDR_DataRegionEnd);
InConstantPool = false;
}
if (MI->getOpcode() == Mips::CONSTPOOL_ENTRY) {
// CONSTPOOL_ENTRY - This instruction represents a floating
//constant pool in the function. The first operand is the ID#
// for this instruction, the second is the index into the
// MachineConstantPool that this is, the third is the size in
// bytes of this constant pool entry.
// The required alignment is specified on the basic block holding this MI.
//
unsigned LabelId = (unsigned)MI->getOperand(0).getImm();
unsigned CPIdx = (unsigned)MI->getOperand(1).getIndex();
// If this is the first entry of the pool, mark it.
if (!InConstantPool) {
OutStreamer.EmitDataRegion(MCDR_DataRegion);
InConstantPool = true;
}
OutStreamer.EmitLabel(GetCPISymbol(LabelId));
const MachineConstantPoolEntry &MCPE = MCP->getConstants()[CPIdx];
if (MCPE.isMachineConstantPoolEntry())
EmitMachineConstantPoolValue(MCPE.Val.MachineCPVal);
else
EmitGlobalConstant(MCPE.Val.ConstVal);
return;
}
MachineBasicBlock::const_instr_iterator I = MI;
MachineBasicBlock::const_instr_iterator E = MI->getParent()->instr_end();
do {
// Do any auto-generated pseudo lowerings.
if (emitPseudoExpansionLowering(OutStreamer, &*I))
continue;
// The inMips16Mode() test is not permanent.
// Some instructions are marked as pseudo right now which
// would make the test fail for the wrong reason but
// that will be fixed soon. We need this here because we are
// removing another test for this situation downstream in the
// callchain.
//
if (I->isPseudo() && !Subtarget->inMips16Mode()
&& !isLongBranchPseudo(I->getOpcode()))
llvm_unreachable("Pseudo opcode found in EmitInstruction()");
MCInst TmpInst0;
MCInstLowering.Lower(I, TmpInst0);
EmitToStreamer(OutStreamer, TmpInst0);
} while ((++I != E) && I->isInsideBundle()); // Delay slot check
}
//===----------------------------------------------------------------------===//
//
// 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 directives
//===----------------------------------------------------------------------===//
// Create a bitmask with all callee saved registers for CPU or Floating Point
// registers. For CPU registers consider RA, GP and FP for saving if necessary.
void MipsAsmPrinter::printSavedRegsBitmask() {
// CPU and FPU Saved Registers Bitmasks
unsigned CPUBitmask = 0, FPUBitmask = 0;
int CPUTopSavedRegOff, FPUTopSavedRegOff;
// Set the CPU and FPU Bitmasks
const MachineFrameInfo *MFI = MF->getFrameInfo();
const std::vector<CalleeSavedInfo> &CSI = MFI->getCalleeSavedInfo();
// size of stack area to which FP callee-saved regs are saved.
unsigned CPURegSize = Mips::GPR32RegClass.getSize();
unsigned FGR32RegSize = Mips::FGR32RegClass.getSize();
unsigned AFGR64RegSize = Mips::AFGR64RegClass.getSize();
bool HasAFGR64Reg = false;
unsigned CSFPRegsSize = 0;
unsigned i, e = CSI.size();
// Set FPU Bitmask.
for (i = 0; i != e; ++i) {
unsigned Reg = CSI[i].getReg();
if (Mips::GPR32RegClass.contains(Reg))
break;
unsigned RegNum = TM.getRegisterInfo()->getEncodingValue(Reg);
if (Mips::AFGR64RegClass.contains(Reg)) {
FPUBitmask |= (3 << RegNum);
CSFPRegsSize += AFGR64RegSize;
HasAFGR64Reg = true;
continue;
}
FPUBitmask |= (1 << RegNum);
CSFPRegsSize += FGR32RegSize;
}
// Set CPU Bitmask.
for (; i != e; ++i) {
unsigned Reg = CSI[i].getReg();
unsigned RegNum = TM.getRegisterInfo()->getEncodingValue(Reg);
CPUBitmask |= (1 << RegNum);
}
// FP Regs are saved right below where the virtual frame pointer points to.
FPUTopSavedRegOff = FPUBitmask ?
(HasAFGR64Reg ? -AFGR64RegSize : -FGR32RegSize) : 0;
// CPU Regs are saved below FP Regs.
CPUTopSavedRegOff = CPUBitmask ? -CSFPRegsSize - CPURegSize : 0;
MipsTargetStreamer &TS = getTargetStreamer();
// Print CPUBitmask
TS.emitMask(CPUBitmask, CPUTopSavedRegOff);
// Print FPUBitmask
TS.emitFMask(FPUBitmask, FPUTopSavedRegOff);
}
//===----------------------------------------------------------------------===//
// Frame and Set directives
//===----------------------------------------------------------------------===//
/// Frame Directive
void MipsAsmPrinter::emitFrameDirective() {
const TargetRegisterInfo &RI = *TM.getRegisterInfo();
unsigned stackReg = RI.getFrameRegister(*MF);
unsigned returnReg = RI.getRARegister();
unsigned stackSize = MF->getFrameInfo()->getStackSize();
getTargetStreamer().emitFrame(stackReg, stackSize, returnReg);
}
/// Emit Set directives.
const char *MipsAsmPrinter::getCurrentABIString() const {
switch (Subtarget->getTargetABI()) {
case MipsSubtarget::O32: return "abi32";
case MipsSubtarget::N32: return "abiN32";
case MipsSubtarget::N64: return "abi64";
case MipsSubtarget::EABI: return "eabi32"; // TODO: handle eabi64
default: llvm_unreachable("Unknown Mips ABI");
}
}
void MipsAsmPrinter::EmitFunctionEntryLabel() {
MipsTargetStreamer &TS = getTargetStreamer();
// NaCl sandboxing requires that indirect call instructions are masked.
// This means that function entry points should be bundle-aligned.
if (Subtarget->isTargetNaCl())
EmitAlignment(std::max(MF->getAlignment(), MIPS_NACL_BUNDLE_ALIGN));
if (Subtarget->inMicroMipsMode())
TS.emitDirectiveSetMicroMips();
else
TS.emitDirectiveSetNoMicroMips();
if (Subtarget->inMips16Mode())
TS.emitDirectiveSetMips16();
else
TS.emitDirectiveSetNoMips16();
TS.emitDirectiveEnt(*CurrentFnSym);
OutStreamer.EmitLabel(CurrentFnSym);
}
/// EmitFunctionBodyStart - Targets can override this to emit stuff before
/// the first basic block in the function.
void MipsAsmPrinter::EmitFunctionBodyStart() {
MipsTargetStreamer &TS = getTargetStreamer();
MCInstLowering.Initialize(&MF->getContext());
bool IsNakedFunction =
MF->getFunction()->
getAttributes().hasAttribute(AttributeSet::FunctionIndex,
Attribute::Naked);
if (!IsNakedFunction)
emitFrameDirective();
if (!IsNakedFunction)
printSavedRegsBitmask();
if (!Subtarget->inMips16Mode()) {
TS.emitDirectiveSetNoReorder();
TS.emitDirectiveSetNoMacro();
TS.emitDirectiveSetNoAt();
}
}
/// EmitFunctionBodyEnd - Targets can override this to emit stuff after
/// the last basic block in the function.
void MipsAsmPrinter::EmitFunctionBodyEnd() {
MipsTargetStreamer &TS = getTargetStreamer();
// There are instruction for this macros, but they must
// always be at the function end, and we can't emit and
// break with BB logic.
if (!Subtarget->inMips16Mode()) {
TS.emitDirectiveSetAt();
TS.emitDirectiveSetMacro();
TS.emitDirectiveSetReorder();
}
TS.emitDirectiveEnd(CurrentFnSym->getName());
// Make sure to terminate any constant pools that were at the end
// of the function.
if (!InConstantPool)
return;
InConstantPool = false;
OutStreamer.EmitDataRegion(MCDR_DataRegionEnd);
}
/// isBlockOnlyReachableByFallthough - Return true if the basic block has
/// exactly one predecessor and the control transfer mechanism between
/// the predecessor and this block is a fall-through.
bool MipsAsmPrinter::isBlockOnlyReachableByFallthrough(const MachineBasicBlock*
MBB) const {
// The predecessor has to be immediately before this block.
const MachineBasicBlock *Pred = *MBB->pred_begin();
// If the predecessor is a switch statement, assume a jump table
// implementation, so it is not a fall through.
if (const BasicBlock *bb = Pred->getBasicBlock())
if (isa<SwitchInst>(bb->getTerminator()))
return false;
// If this is a landing pad, it isn't a fall through. If it has no preds,
// then nothing falls through to it.
if (MBB->isLandingPad() || MBB->pred_empty())
return false;
// If there isn't exactly one predecessor, it can't be a fall through.
MachineBasicBlock::const_pred_iterator PI = MBB->pred_begin(), PI2 = PI;
++PI2;
if (PI2 != MBB->pred_end())
return false;
// The predecessor has to be immediately before this block.
if (!Pred->isLayoutSuccessor(MBB))
return false;
// If the block is completely empty, then it definitely does fall through.
if (Pred->empty())
return true;
// Otherwise, check the last instruction.
// Check if the last terminator is an unconditional branch.
MachineBasicBlock::const_iterator I = Pred->end();
while (I != Pred->begin() && !(--I)->isTerminator()) ;
return !I->isBarrier();
}
// Print out an operand for an inline asm expression.
bool MipsAsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNum,
unsigned AsmVariant,const char *ExtraCode,
raw_ostream &O) {
// Does this asm operand have a single letter operand modifier?
if (ExtraCode && ExtraCode[0]) {
if (ExtraCode[1] != 0) return true; // Unknown modifier.
const MachineOperand &MO = MI->getOperand(OpNum);
switch (ExtraCode[0]) {
default:
// See if this is a generic print operand
return AsmPrinter::PrintAsmOperand(MI,OpNum,AsmVariant,ExtraCode,O);
case 'X': // hex const int
if ((MO.getType()) != MachineOperand::MO_Immediate)
return true;
O << "0x" << StringRef(utohexstr(MO.getImm())).lower();
return false;
case 'x': // hex const int (low 16 bits)
if ((MO.getType()) != MachineOperand::MO_Immediate)
return true;
O << "0x" << StringRef(utohexstr(MO.getImm() & 0xffff)).lower();
return false;
case 'd': // decimal const int
if ((MO.getType()) != MachineOperand::MO_Immediate)
return true;
O << MO.getImm();
return false;
case 'm': // decimal const int minus 1
if ((MO.getType()) != MachineOperand::MO_Immediate)
return true;
O << MO.getImm() - 1;
return false;
case 'z': {
// $0 if zero, regular printing otherwise
if (MO.getType() != MachineOperand::MO_Immediate)
return true;
int64_t Val = MO.getImm();
if (Val)
O << Val;
else
O << "$0";
return false;
}
case 'D': // Second part of a double word register operand
case 'L': // Low order register of a double word register operand
case 'M': // High order register of a double word register operand
{
if (OpNum == 0)
return true;
const MachineOperand &FlagsOP = MI->getOperand(OpNum - 1);
if (!FlagsOP.isImm())
return true;
unsigned Flags = FlagsOP.getImm();
unsigned NumVals = InlineAsm::getNumOperandRegisters(Flags);
// Number of registers represented by this operand. We are looking
// for 2 for 32 bit mode and 1 for 64 bit mode.
if (NumVals != 2) {
if (Subtarget->isGP64bit() && NumVals == 1 && MO.isReg()) {
unsigned Reg = MO.getReg();
O << '$' << MipsInstPrinter::getRegisterName(Reg);
return false;
}
return true;
}
unsigned RegOp = OpNum;
if (!Subtarget->isGP64bit()){
// Endianess reverses which register holds the high or low value
// between M and L.
switch(ExtraCode[0]) {
case 'M':
RegOp = (Subtarget->isLittle()) ? OpNum + 1 : OpNum;
break;
case 'L':
RegOp = (Subtarget->isLittle()) ? OpNum : OpNum + 1;
break;
case 'D': // Always the second part
RegOp = OpNum + 1;
}
if (RegOp >= MI->getNumOperands())
return true;
const MachineOperand &MO = MI->getOperand(RegOp);
if (!MO.isReg())
return true;
unsigned Reg = MO.getReg();
O << '$' << MipsInstPrinter::getRegisterName(Reg);
return false;
}
}
case 'w':
// Print MSA registers for the 'f' constraint
// In LLVM, the 'w' modifier doesn't need to do anything.
// We can just call printOperand as normal.
break;
}
}
printOperand(MI, OpNum, O);
return false;
}
bool MipsAsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI,
unsigned OpNum, unsigned AsmVariant,
const char *ExtraCode,
raw_ostream &O) {
int Offset = 0;
// Currently we are expecting either no ExtraCode or 'D'
if (ExtraCode) {
if (ExtraCode[0] == 'D')
Offset = 4;
else
return true; // Unknown modifier.
}
const MachineOperand &MO = MI->getOperand(OpNum);
assert(MO.isReg() && "unexpected inline asm memory operand");
O << Offset << "($" << MipsInstPrinter::getRegisterName(MO.getReg()) << ")";
return false;
}
void MipsAsmPrinter::printOperand(const MachineInstr *MI, int opNum,
raw_ostream &O) {
const DataLayout *DL = TM.getDataLayout();
const MachineOperand &MO = MI->getOperand(opNum);
bool closeP = false;
if (MO.getTargetFlags())
closeP = true;
switch(MO.getTargetFlags()) {
case MipsII::MO_GPREL: O << "%gp_rel("; break;
case MipsII::MO_GOT_CALL: O << "%call16("; break;
case MipsII::MO_GOT: O << "%got("; break;
case MipsII::MO_ABS_HI: O << "%hi("; break;
case MipsII::MO_ABS_LO: O << "%lo("; break;
case MipsII::MO_TLSGD: O << "%tlsgd("; break;
case MipsII::MO_GOTTPREL: O << "%gottprel("; break;
case MipsII::MO_TPREL_HI: O << "%tprel_hi("; break;
case MipsII::MO_TPREL_LO: O << "%tprel_lo("; break;
case MipsII::MO_GPOFF_HI: O << "%hi(%neg(%gp_rel("; break;
case MipsII::MO_GPOFF_LO: O << "%lo(%neg(%gp_rel("; break;
case MipsII::MO_GOT_DISP: O << "%got_disp("; break;
case MipsII::MO_GOT_PAGE: O << "%got_page("; break;
case MipsII::MO_GOT_OFST: O << "%got_ofst("; break;
}
switch (MO.getType()) {
case MachineOperand::MO_Register:
O << '$'
<< StringRef(MipsInstPrinter::getRegisterName(MO.getReg())).lower();
break;
case MachineOperand::MO_Immediate:
O << MO.getImm();
break;
case MachineOperand::MO_MachineBasicBlock:
O << *MO.getMBB()->getSymbol();
return;
case MachineOperand::MO_GlobalAddress:
O << *getSymbol(MO.getGlobal());
break;
case MachineOperand::MO_BlockAddress: {
MCSymbol *BA = GetBlockAddressSymbol(MO.getBlockAddress());
O << BA->getName();
break;
}
case MachineOperand::MO_ConstantPoolIndex:
O << DL->getPrivateGlobalPrefix() << "CPI"
<< getFunctionNumber() << "_" << MO.getIndex();
if (MO.getOffset())
O << "+" << MO.getOffset();
break;
default:
llvm_unreachable("<unknown operand type>");
}
if (closeP) O << ")";
}
void MipsAsmPrinter::printUnsignedImm(const MachineInstr *MI, int opNum,
raw_ostream &O) {
const MachineOperand &MO = MI->getOperand(opNum);
if (MO.isImm())
O << (unsigned short int)MO.getImm();
else
printOperand(MI, opNum, O);
}
void MipsAsmPrinter::printUnsignedImm8(const MachineInstr *MI, int opNum,
raw_ostream &O) {
const MachineOperand &MO = MI->getOperand(opNum);
if (MO.isImm())
O << (unsigned short int)(unsigned char)MO.getImm();
else
printOperand(MI, opNum, O);
}
void MipsAsmPrinter::
printMemOperand(const MachineInstr *MI, int opNum, raw_ostream &O) {
// Load/Store memory operands -- imm($reg)
// If PIC target the target is loaded as the
// pattern lw $25,%call16($28)
printOperand(MI, opNum+1, O);
O << "(";
printOperand(MI, opNum, O);
O << ")";
}
void MipsAsmPrinter::
printMemOperandEA(const MachineInstr *MI, int opNum, raw_ostream &O) {
// when using stack locations for not load/store instructions
// print the same way as all normal 3 operand instructions.
printOperand(MI, opNum, O);
O << ", ";
printOperand(MI, opNum+1, O);
return;
}
void MipsAsmPrinter::
printFCCOperand(const MachineInstr *MI, int opNum, raw_ostream &O,
const char *Modifier) {
const MachineOperand &MO = MI->getOperand(opNum);
O << Mips::MipsFCCToString((Mips::CondCode)MO.getImm());
}
void MipsAsmPrinter::EmitStartOfAsmFile(Module &M) {
// TODO: Need to add -mabicalls and -mno-abicalls flags.
// Currently we assume that -mabicalls is the default.
bool IsABICalls = true;
if (IsABICalls) {
getTargetStreamer().emitDirectiveAbiCalls();
Reloc::Model RM = Subtarget->getRelocationModel();
// FIXME: This condition should be a lot more complicated that it is here.
// Ideally it should test for properties of the ABI and not the ABI
// itself.
// For the moment, I'm only correcting enough to make MIPS-IV work.
if (RM == Reloc::Static && !Subtarget->isABI_N64())
getTargetStreamer().emitDirectiveOptionPic0();
}
// Tell the assembler which ABI we are using
std::string SectionName = std::string(".mdebug.") + getCurrentABIString();
OutStreamer.SwitchSection(OutContext.getELFSection(
SectionName, ELF::SHT_PROGBITS, 0, SectionKind::getDataRel()));
// NaN: At the moment we only support:
// 1. .nan legacy (default)
// 2. .nan 2008
Subtarget->isNaN2008() ? getTargetStreamer().emitDirectiveNaN2008()
: getTargetStreamer().emitDirectiveNaNLegacy();
// TODO: handle O64 ABI
if (Subtarget->isABI_EABI()) {
if (Subtarget->isGP32bit())
OutStreamer.SwitchSection(
OutContext.getELFSection(".gcc_compiled_long32", ELF::SHT_PROGBITS, 0,
SectionKind::getDataRel()));
else
OutStreamer.SwitchSection(
OutContext.getELFSection(".gcc_compiled_long64", ELF::SHT_PROGBITS, 0,
SectionKind::getDataRel()));
}
}
void MipsAsmPrinter::EmitJal(MCSymbol *Symbol) {
MCInst I;
I.setOpcode(Mips::JAL);
I.addOperand(
MCOperand::CreateExpr(MCSymbolRefExpr::Create(Symbol, OutContext)));
OutStreamer.EmitInstruction(I, getSubtargetInfo());
}
void MipsAsmPrinter::EmitInstrReg(unsigned Opcode, unsigned Reg) {
MCInst I;
I.setOpcode(Opcode);
I.addOperand(MCOperand::CreateReg(Reg));
OutStreamer.EmitInstruction(I, getSubtargetInfo());
}
void MipsAsmPrinter::EmitInstrRegReg(unsigned Opcode, unsigned Reg1,
unsigned Reg2) {
MCInst I;
//
// Because of the current td files for Mips32, the operands for MTC1
// appear backwards from their normal assembly order. It's not a trivial
// change to fix this in the td file so we adjust for it here.
//
if (Opcode == Mips::MTC1) {
unsigned Temp = Reg1;
Reg1 = Reg2;
Reg2 = Temp;
}
I.setOpcode(Opcode);
I.addOperand(MCOperand::CreateReg(Reg1));
I.addOperand(MCOperand::CreateReg(Reg2));
OutStreamer.EmitInstruction(I, getSubtargetInfo());
}
void MipsAsmPrinter::EmitInstrRegRegReg(unsigned Opcode, unsigned Reg1,
unsigned Reg2, unsigned Reg3) {
MCInst I;
I.setOpcode(Opcode);
I.addOperand(MCOperand::CreateReg(Reg1));
I.addOperand(MCOperand::CreateReg(Reg2));
I.addOperand(MCOperand::CreateReg(Reg3));
OutStreamer.EmitInstruction(I, getSubtargetInfo());
}
void MipsAsmPrinter::EmitMovFPIntPair(unsigned MovOpc, unsigned Reg1,
unsigned Reg2, unsigned FPReg1,
unsigned FPReg2, bool LE) {
if (!LE) {
unsigned temp = Reg1;
Reg1 = Reg2;
Reg2 = temp;
}
EmitInstrRegReg(MovOpc, Reg1, FPReg1);
EmitInstrRegReg(MovOpc, Reg2, FPReg2);
}
void MipsAsmPrinter::EmitSwapFPIntParams(Mips16HardFloatInfo::FPParamVariant PV,
bool LE, bool ToFP) {
using namespace Mips16HardFloatInfo;
unsigned MovOpc = ToFP ? Mips::MTC1 : Mips::MFC1;
switch (PV) {
case FSig:
EmitInstrRegReg(MovOpc, Mips::A0, Mips::F12);
break;
case FFSig:
EmitMovFPIntPair(MovOpc, Mips::A0, Mips::A1, Mips::F12, Mips::F14, LE);
break;
case FDSig:
EmitInstrRegReg(MovOpc, Mips::A0, Mips::F12);
EmitMovFPIntPair(MovOpc, Mips::A2, Mips::A3, Mips::F14, Mips::F15, LE);
break;
case DSig:
EmitMovFPIntPair(MovOpc, Mips::A0, Mips::A1, Mips::F12, Mips::F13, LE);
break;
case DDSig:
EmitMovFPIntPair(MovOpc, Mips::A0, Mips::A1, Mips::F12, Mips::F13, LE);
EmitMovFPIntPair(MovOpc, Mips::A2, Mips::A3, Mips::F14, Mips::F15, LE);
break;
case DFSig:
EmitMovFPIntPair(MovOpc, Mips::A0, Mips::A1, Mips::F12, Mips::F13, LE);
EmitInstrRegReg(MovOpc, Mips::A2, Mips::F14);
break;
case NoSig:
return;
}
}
void
MipsAsmPrinter::EmitSwapFPIntRetval(Mips16HardFloatInfo::FPReturnVariant RV,
bool LE) {
using namespace Mips16HardFloatInfo;
unsigned MovOpc = Mips::MFC1;
switch (RV) {
case FRet:
EmitInstrRegReg(MovOpc, Mips::V0, Mips::F0);
break;
case DRet:
EmitMovFPIntPair(MovOpc, Mips::V0, Mips::V1, Mips::F0, Mips::F1, LE);
break;
case CFRet:
EmitMovFPIntPair(MovOpc, Mips::V0, Mips::V1, Mips::F0, Mips::F1, LE);
break;
case CDRet:
EmitMovFPIntPair(MovOpc, Mips::V0, Mips::V1, Mips::F0, Mips::F1, LE);
EmitMovFPIntPair(MovOpc, Mips::A0, Mips::A1, Mips::F2, Mips::F3, LE);
break;
case NoFPRet:
break;
}
}
void MipsAsmPrinter::EmitFPCallStub(
const char *Symbol, const Mips16HardFloatInfo::FuncSignature *Signature) {
MCSymbol *MSymbol = OutContext.GetOrCreateSymbol(StringRef(Symbol));
using namespace Mips16HardFloatInfo;
bool LE = Subtarget->isLittle();
//
// .global xxxx
//
OutStreamer.EmitSymbolAttribute(MSymbol, MCSA_Global);
const char *RetType;
//
// make the comment field identifying the return and parameter
// types of the floating point stub
// # Stub function to call rettype xxxx (params)
//
switch (Signature->RetSig) {
case FRet:
RetType = "float";
break;
case DRet:
RetType = "double";
break;
case CFRet:
RetType = "complex";
break;
case CDRet:
RetType = "double complex";
break;
case NoFPRet:
RetType = "";
break;
}
const char *Parms;
switch (Signature->ParamSig) {
case FSig:
Parms = "float";
break;
case FFSig:
Parms = "float, float";
break;
case FDSig:
Parms = "float, double";
break;
case DSig:
Parms = "double";
break;
case DDSig:
Parms = "double, double";
break;
case DFSig:
Parms = "double, float";
break;
case NoSig:
Parms = "";
break;
}
OutStreamer.AddComment("\t# Stub function to call " + Twine(RetType) + " " +
Twine(Symbol) + " (" + Twine(Parms) + ")");
//
// probably not necessary but we save and restore the current section state
//
OutStreamer.PushSection();
//
// .section mips16.call.fpxxxx,"ax",@progbits
//
const MCSectionELF *M = OutContext.getELFSection(
".mips16.call.fp." + std::string(Symbol), ELF::SHT_PROGBITS,
ELF::SHF_ALLOC | ELF::SHF_EXECINSTR, SectionKind::getText());
OutStreamer.SwitchSection(M, nullptr);
//
// .align 2
//
OutStreamer.EmitValueToAlignment(4);
MipsTargetStreamer &TS = getTargetStreamer();
//
// .set nomips16
// .set nomicromips
//
TS.emitDirectiveSetNoMips16();
TS.emitDirectiveSetNoMicroMips();
//
// .ent __call_stub_fp_xxxx
// .type __call_stub_fp_xxxx,@function
// __call_stub_fp_xxxx:
//
std::string x = "__call_stub_fp_" + std::string(Symbol);
MCSymbol *Stub = OutContext.GetOrCreateSymbol(StringRef(x));
TS.emitDirectiveEnt(*Stub);
MCSymbol *MType =
OutContext.GetOrCreateSymbol("__call_stub_fp_" + Twine(Symbol));
OutStreamer.EmitSymbolAttribute(MType, MCSA_ELF_TypeFunction);
OutStreamer.EmitLabel(Stub);
//
// we just handle non pic for now. these function will not be
// called otherwise. when the full stub generation is moved here
// we need to deal with pic.
//
if (Subtarget->getRelocationModel() == Reloc::PIC_)
llvm_unreachable("should not be here if we are compiling pic");
TS.emitDirectiveSetReorder();
//
// We need to add a MipsMCExpr class to MCTargetDesc to fully implement
// stubs without raw text but this current patch is for compiler generated
// functions and they all return some value.
// The calling sequence for non pic is different in that case and we need
// to implement %lo and %hi in order to handle the case of no return value
// See the corresponding method in Mips16HardFloat for details.
//
// mov the return address to S2.
// we have no stack space to store it and we are about to make another call.
// We need to make sure that the enclosing function knows to save S2
// This should have already been handled.
//
// Mov $18, $31
EmitInstrRegRegReg(Mips::ADDu, Mips::S2, Mips::RA, Mips::ZERO);
EmitSwapFPIntParams(Signature->ParamSig, LE, true);
// Jal xxxx
//
EmitJal(MSymbol);
// fix return values
EmitSwapFPIntRetval(Signature->RetSig, LE);
//
// do the return
// if (Signature->RetSig == NoFPRet)
// llvm_unreachable("should not be any stubs here with no return value");
// else
EmitInstrReg(Mips::JR, Mips::S2);
MCSymbol *Tmp = OutContext.CreateTempSymbol();
OutStreamer.EmitLabel(Tmp);
const MCSymbolRefExpr *E = MCSymbolRefExpr::Create(Stub, OutContext);
const MCSymbolRefExpr *T = MCSymbolRefExpr::Create(Tmp, OutContext);
const MCExpr *T_min_E = MCBinaryExpr::CreateSub(T, E, OutContext);
OutStreamer.EmitELFSize(Stub, T_min_E);
TS.emitDirectiveEnd(x);
OutStreamer.PopSection();
}
void MipsAsmPrinter::EmitEndOfAsmFile(Module &M) {
// Emit needed stubs
//
for (std::map<
const char *,
const llvm::Mips16HardFloatInfo::FuncSignature *>::const_iterator
it = StubsNeeded.begin();
it != StubsNeeded.end(); ++it) {
const char *Symbol = it->first;
const llvm::Mips16HardFloatInfo::FuncSignature *Signature = it->second;
EmitFPCallStub(Symbol, Signature);
}
// return to the text section
OutStreamer.SwitchSection(OutContext.getObjectFileInfo()->getTextSection());
}
void MipsAsmPrinter::PrintDebugValueComment(const MachineInstr *MI,
raw_ostream &OS) {
// TODO: implement
}
// Align all targets of indirect branches on bundle size. Used only if target
// is NaCl.
void MipsAsmPrinter::NaClAlignIndirectJumpTargets(MachineFunction &MF) {
// Align all blocks that are jumped to through jump table.
if (MachineJumpTableInfo *JtInfo = MF.getJumpTableInfo()) {
const std::vector<MachineJumpTableEntry> &JT = JtInfo->getJumpTables();
for (unsigned I = 0; I < JT.size(); ++I) {
const std::vector<MachineBasicBlock*> &MBBs = JT[I].MBBs;
for (unsigned J = 0; J < MBBs.size(); ++J)
MBBs[J]->setAlignment(MIPS_NACL_BUNDLE_ALIGN);
}
}
// If basic block address is taken, block can be target of indirect branch.
for (MachineFunction::iterator MBB = MF.begin(), E = MF.end();
MBB != E; ++MBB) {
if (MBB->hasAddressTaken())
MBB->setAlignment(MIPS_NACL_BUNDLE_ALIGN);
}
}
bool MipsAsmPrinter::isLongBranchPseudo(int Opcode) const {
return (Opcode == Mips::LONG_BRANCH_LUi
|| Opcode == Mips::LONG_BRANCH_ADDiu
|| Opcode == Mips::LONG_BRANCH_LUi64
|| Opcode == Mips::LONG_BRANCH_DADDiu);
}
// Force static initialization.
extern "C" void LLVMInitializeMipsAsmPrinter() {
RegisterAsmPrinter<MipsAsmPrinter> X(TheMipsTarget);
RegisterAsmPrinter<MipsAsmPrinter> Y(TheMipselTarget);
RegisterAsmPrinter<MipsAsmPrinter> A(TheMips64Target);
RegisterAsmPrinter<MipsAsmPrinter> B(TheMips64elTarget);
}