llvm-6502/lib/Target/PowerPC/PPCAsmPrinter.cpp
Chris Lattner 469ab79584 Print float constants as 4 byte values.
Also, fix endianness problems when cross compiling from little-endian host.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@15847 91177308-0d34-0410-b5e6-96231b3b80d8
2004-08-17 02:48:44 +00:00

663 lines
22 KiB
C++

//===-- PPC32AsmPrinter.cpp - Print machine instrs to PowerPC assembly ----===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and 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 PowerPC assembly language. This printer is
// the output mechanism used by `llc'.
//
// Documentation at http://developer.apple.com/documentation/DeveloperTools/
// Reference/Assembler/ASMIntroduction/chapter_1_section_1.html
//
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "asmprinter"
#include "PowerPC.h"
#include "PowerPCInstrInfo.h"
#include "PowerPCTargetMachine.h"
#include "llvm/Constants.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Module.h"
#include "llvm/Assembly/Writer.h"
#include "llvm/CodeGen/AsmPrinter.h"
#include "llvm/CodeGen/MachineConstantPool.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/CodeGen/ValueTypes.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Support/Mangler.h"
#include "Support/CommandLine.h"
#include "Support/Debug.h"
#include "Support/Statistic.h"
#include "Support/StringExtras.h"
#include <set>
using namespace llvm;
namespace {
Statistic<> EmittedInsts("asm-printer", "Number of machine instrs printed");
struct PowerPCAsmPrinter : public AsmPrinter {
std::set<std::string> FnStubs, GVStubs, LinkOnceStubs;
std::set<std::string> Strings;
PowerPCAsmPrinter(std::ostream &O, TargetMachine &TM)
: AsmPrinter(O, TM), LabelNumber(0) {
UsesUnderscorePrefix = 1;
}
/// Unique incrementer for label values for referencing Global values.
///
unsigned LabelNumber;
virtual const char *getPassName() const {
return "PowerPC Assembly Printer";
}
PowerPCTargetMachine &getTM() {
return static_cast<PowerPCTargetMachine&>(TM);
}
/// printInstruction - This method is automatically generated by tablegen
/// from the instruction set description. This method returns true if the
/// machine instruction was sufficiently described to print it, otherwise it
/// returns false.
bool printInstruction(const MachineInstr *MI);
void printMachineInstruction(const MachineInstr *MI);
void printOp(const MachineOperand &MO, bool LoadAddrOp = false);
void printImmOp(const MachineOperand &MO, unsigned ArgType);
void printOperand(const MachineInstr *MI, unsigned OpNo, MVT::ValueType VT){
const MachineOperand &MO = MI->getOperand(OpNo);
if (MO.getType() == MachineOperand::MO_MachineRegister) {
assert(MRegisterInfo::isPhysicalRegister(MO.getReg())&&"Not physreg??");
O << LowercaseString(TM.getRegisterInfo()->get(MO.getReg()).Name);
} else if (MO.isImmediate()) {
O << MO.getImmedValue();
} else {
printOp(MO);
}
}
void printU16ImmOperand(const MachineInstr *MI, unsigned OpNo,
MVT::ValueType VT) {
O << (unsigned short)MI->getOperand(OpNo).getImmedValue();
}
void printConstantPool(MachineConstantPool *MCP);
bool runOnMachineFunction(MachineFunction &F);
bool doFinalization(Module &M);
void emitGlobalConstant(const Constant* CV);
};
} // end of anonymous namespace
/// createPPC32AsmPrinterPass - Returns a pass that prints the PPC
/// 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 or not.
///
FunctionPass *llvm::createPPCAsmPrinter(std::ostream &o,TargetMachine &tm) {
return new PowerPCAsmPrinter(o, tm);
}
// Include the auto-generated portion of the assembly writer
#include "PowerPCGenAsmWriter.inc"
/// toOctal - Convert the low order bits of X into an octal digit.
///
static inline char toOctal(int X) {
return (X&7)+'0';
}
/// getAsCString - Return the specified array as a C compatible
/// string, only if the predicate isString is true.
///
static void printAsCString(std::ostream &O, const ConstantArray *CVA) {
assert(CVA->isString() && "Array is not string compatible!");
O << "\"";
for (unsigned i = 0; i != CVA->getNumOperands(); ++i) {
unsigned char C = cast<ConstantInt>(CVA->getOperand(i))->getRawValue();
if (C == '"') {
O << "\\\"";
} else if (C == '\\') {
O << "\\\\";
} else if (isprint(C)) {
O << C;
} else {
switch(C) {
case '\b': O << "\\b"; break;
case '\f': O << "\\f"; break;
case '\n': O << "\\n"; break;
case '\r': O << "\\r"; break;
case '\t': O << "\\t"; break;
default:
O << '\\';
O << toOctal(C >> 6);
O << toOctal(C >> 3);
O << toOctal(C >> 0);
break;
}
}
}
O << "\"";
}
// Print a constant value or values, with the appropriate storage class as a
// prefix.
void PowerPCAsmPrinter::emitGlobalConstant(const Constant *CV) {
const TargetData &TD = TM.getTargetData();
if (CV->isNullValue()) {
O << "\t.space\t" << TD.getTypeSize(CV->getType()) << "\n";
return;
} else if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV)) {
if (CVA->isString()) {
O << "\t.ascii\t";
printAsCString(O, CVA);
O << "\n";
} else { // Not a string. Print the values in successive locations
for (unsigned i = 0, e = CVA->getNumOperands(); i != e; ++i)
emitGlobalConstant(CVA->getOperand(i));
}
return;
} else if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV)) {
// Print the fields in successive locations. Pad to align if needed!
const StructLayout *cvsLayout = TD.getStructLayout(CVS->getType());
unsigned sizeSoFar = 0;
for (unsigned i = 0, e = CVS->getNumOperands(); i != e; ++i) {
const Constant* field = CVS->getOperand(i);
// Check if padding is needed and insert one or more 0s.
unsigned fieldSize = TD.getTypeSize(field->getType());
unsigned padSize = ((i == e-1? cvsLayout->StructSize
: cvsLayout->MemberOffsets[i+1])
- cvsLayout->MemberOffsets[i]) - fieldSize;
sizeSoFar += fieldSize + padSize;
// Now print the actual field value
emitGlobalConstant(field);
// Insert the field padding unless it's zero bytes...
if (padSize)
O << "\t.space\t " << padSize << "\n";
}
assert(sizeSoFar == cvsLayout->StructSize &&
"Layout of constant struct may be incorrect!");
return;
} else if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV)) {
// FP Constants are printed as integer constants to avoid losing
// precision...
double Val = CFP->getValue();
if (CFP->getType() == Type::DoubleTy) {
union DU { // Abide by C TBAA rules
double FVal;
uint64_t UVal;
} U;
U.FVal = Val;
if (TD.isBigEndian()) {
O << ".long\t" << unsigned(U.UVal >> 32)
<< "\t; double most significant word " << Val << "\n";
O << ".long\t" << unsigned(U.UVal)
<< "\t; double least significant word " << Val << "\n";
} else {
O << ".long\t" << unsigned(U.UVal)
<< "\t; double least significant word " << Val << "\n";
O << ".long\t" << unsigned(U.UVal >> 32)
<< "\t; double most significant word " << Val << "\n";
}
return;
} else {
union FU { // Abide by C TBAA rules
float FVal;
int32_t UVal;
} U;
U.FVal = Val;
O << ".long\t" << U.UVal << "\t; float " << Val << "\n";
return;
}
} else if (CV->getType() == Type::ULongTy || CV->getType() == Type::LongTy) {
if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
uint64_t Val = CI->getRawValue();
if (TD.isBigEndian()) {
O << ".long\t" << unsigned(Val >> 32)
<< "\t; Double-word most significant word " << Val << "\n";
O << ".long\t" << unsigned(Val)
<< "\t; Double-word least significant word " << Val << "\n";
} else {
O << ".long\t" << unsigned(Val)
<< "\t; Double-word least significant word " << Val << "\n";
O << ".long\t" << unsigned(Val >> 32)
<< "\t; Double-word most significant word " << Val << "\n";
}
return;
}
}
const Type *type = CV->getType();
O << "\t";
switch (type->getTypeID()) {
case Type::UByteTyID: case Type::SByteTyID:
O << ".byte";
break;
case Type::UShortTyID: case Type::ShortTyID:
O << ".short";
break;
case Type::BoolTyID:
case Type::PointerTyID:
case Type::UIntTyID: case Type::IntTyID:
O << ".long";
break;
case Type::ULongTyID: case Type::LongTyID:
assert (0 && "Should have already output double-word constant.");
case Type::FloatTyID: case Type::DoubleTyID:
assert (0 && "Should have already output floating point constant.");
default:
assert (0 && "Can't handle printing this type of thing");
break;
}
O << "\t";
emitConstantValueOnly(CV);
O << "\n";
}
/// printConstantPool - Print to the current output stream assembly
/// representations of the constants in the constant pool MCP. This is
/// used to print out constants which have been "spilled to memory" by
/// the code generator.
///
void PowerPCAsmPrinter::printConstantPool(MachineConstantPool *MCP) {
const std::vector<Constant*> &CP = MCP->getConstants();
const TargetData &TD = TM.getTargetData();
if (CP.empty()) return;
for (unsigned i = 0, e = CP.size(); i != e; ++i) {
O << "\t.const\n";
O << "\t.align " << (unsigned)TD.getTypeAlignment(CP[i]->getType())
<< "\n";
O << ".CPI" << CurrentFnName << "_" << i << ":\t\t\t\t\t;"
<< *CP[i] << "\n";
emitGlobalConstant(CP[i]);
}
}
/// runOnMachineFunction - This uses the printMachineInstruction()
/// method to print assembly for each instruction.
///
bool PowerPCAsmPrinter::runOnMachineFunction(MachineFunction &MF) {
setupMachineFunction(MF);
O << "\n\n";
// Print out constants referenced by the function
printConstantPool(MF.getConstantPool());
// Print out labels for the function.
O << "\t.text\n";
O << "\t.globl\t" << CurrentFnName << "\n";
O << "\t.align 2\n";
O << CurrentFnName << ":\n";
// 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.
O << ".LBB" << CurrentFnName << "_" << I->getNumber() << ":\t; "
<< I->getBasicBlock()->getName() << "\n";
for (MachineBasicBlock::const_iterator II = I->begin(), E = I->end();
II != E; ++II) {
// Print the assembly for the instruction.
O << "\t";
printMachineInstruction(II);
}
}
++LabelNumber;
// We didn't modify anything.
return false;
}
void PowerPCAsmPrinter::printOp(const MachineOperand &MO,
bool LoadAddrOp /* = false */) {
const MRegisterInfo &RI = *TM.getRegisterInfo();
int new_symbol;
switch (MO.getType()) {
case MachineOperand::MO_VirtualRegister:
if (Value *V = MO.getVRegValueOrNull()) {
O << "<" << V->getName() << ">";
return;
}
// FALLTHROUGH
case MachineOperand::MO_MachineRegister:
case MachineOperand::MO_CCRegister:
O << LowercaseString(RI.get(MO.getReg()).Name);
return;
case MachineOperand::MO_SignExtendedImmed:
case MachineOperand::MO_UnextendedImmed:
std::cerr << "printOp() does not handle immediate values\n";
abort();
return;
case MachineOperand::MO_PCRelativeDisp:
std::cerr << "Shouldn't use addPCDisp() when building PPC MachineInstrs";
abort();
return;
case MachineOperand::MO_MachineBasicBlock: {
MachineBasicBlock *MBBOp = MO.getMachineBasicBlock();
O << ".LBB" << Mang->getValueName(MBBOp->getParent()->getFunction())
<< "_" << MBBOp->getNumber() << "\t; "
<< MBBOp->getBasicBlock()->getName();
return;
}
case MachineOperand::MO_ConstantPoolIndex:
O << ".CPI" << CurrentFnName << "_" << MO.getConstantPoolIndex();
return;
case MachineOperand::MO_ExternalSymbol:
O << MO.getSymbolName();
return;
case MachineOperand::MO_GlobalAddress: {
GlobalValue *GV = MO.getGlobal();
std::string Name = Mang->getValueName(GV);
// Dynamically-resolved functions need a stub for the function. Be
// wary however not to output $stub for external functions whose addresses
// are taken. Those should be emitted as $non_lazy_ptr below.
Function *F = dyn_cast<Function>(GV);
if (F && F->isExternal() && !LoadAddrOp &&
getTM().CalledFunctions.count(F)) {
FnStubs.insert(Name);
O << "L" << Name << "$stub";
return;
}
// External global variables need a non-lazily-resolved stub
if (GV->isExternal() && getTM().AddressTaken.count(GV)) {
GVStubs.insert(Name);
O << "L" << Name << "$non_lazy_ptr";
return;
}
if (F && LoadAddrOp && getTM().AddressTaken.count(GV)) {
LinkOnceStubs.insert(Name);
O << "L" << Name << "$non_lazy_ptr";
return;
}
O << Mang->getValueName(GV);
return;
}
default:
O << "<unknown operand type: " << MO.getType() << ">";
return;
}
}
void PowerPCAsmPrinter::printImmOp(const MachineOperand &MO, unsigned ArgType) {
int Imm = MO.getImmedValue();
if (ArgType == PPCII::Simm16 || ArgType == PPCII::Disimm16) {
O << (short)Imm;
} else {
O << Imm;
}
}
/// printMachineInstruction -- Print out a single PowerPC MI in Darwin syntax to
/// the current output stream.
///
void PowerPCAsmPrinter::printMachineInstruction(const MachineInstr *MI) {
++EmittedInsts;
if (printInstruction(MI))
return; // Printer was automatically generated
unsigned Opcode = MI->getOpcode();
const TargetInstrInfo &TII = *TM.getInstrInfo();
const TargetInstrDescriptor &Desc = TII.get(Opcode);
unsigned i;
unsigned ArgCount = MI->getNumOperands();
unsigned ArgType[] = {
(Desc.TSFlags >> PPCII::Arg0TypeShift) & PPCII::ArgTypeMask,
(Desc.TSFlags >> PPCII::Arg1TypeShift) & PPCII::ArgTypeMask,
(Desc.TSFlags >> PPCII::Arg2TypeShift) & PPCII::ArgTypeMask,
(Desc.TSFlags >> PPCII::Arg3TypeShift) & PPCII::ArgTypeMask,
(Desc.TSFlags >> PPCII::Arg4TypeShift) & PPCII::ArgTypeMask
};
assert(((Desc.TSFlags & PPCII::VMX) == 0) &&
"Instruction requires VMX support");
assert(((Desc.TSFlags & PPCII::PPC64) == 0) &&
"Instruction requires 64 bit support");
// CALLpcrel and CALLindirect are handled specially here to print only the
// appropriate number of args that the assembler expects. This is because
// may have many arguments appended to record the uses of registers that are
// holding arguments to the called function.
if (Opcode == PPC::COND_BRANCH) {
std::cerr << "Error: untranslated conditional branch psuedo instruction!\n";
abort();
} else if (Opcode == PPC::IMPLICIT_DEF) {
O << "; IMPLICIT DEF ";
printOp(MI->getOperand(0));
O << "\n";
return;
} else if (Opcode == PPC::CALLpcrel) {
O << TII.getName(Opcode) << " ";
printOp(MI->getOperand(0));
O << "\n";
return;
} else if (Opcode == PPC::CALLindirect) {
O << TII.getName(Opcode) << " ";
printImmOp(MI->getOperand(0), ArgType[0]);
O << ", ";
printImmOp(MI->getOperand(1), ArgType[0]);
O << "\n";
return;
} else if (Opcode == PPC::MovePCtoLR) {
// FIXME: should probably be converted to cout.width and cout.fill
O << "bl \"L0000" << LabelNumber << "$pb\"\n";
O << "\"L0000" << LabelNumber << "$pb\":\n";
O << "\tmflr ";
printOp(MI->getOperand(0));
O << "\n";
return;
}
O << TII.getName(Opcode) << " ";
if (Opcode == PPC::LOADLoDirect || Opcode == PPC::LOADLoIndirect) {
printOp(MI->getOperand(0));
O << ", lo16(";
printOp(MI->getOperand(2), true /* LoadAddrOp */);
O << "-\"L0000" << LabelNumber << "$pb\")";
O << "(";
if (MI->getOperand(1).getReg() == PPC::R0)
O << "0";
else
printOp(MI->getOperand(1));
O << ")\n";
} else if (Opcode == PPC::LOADHiAddr) {
printOp(MI->getOperand(0));
O << ", ";
if (MI->getOperand(1).getReg() == PPC::R0)
O << "0";
else
printOp(MI->getOperand(1));
O << ", ha16(" ;
printOp(MI->getOperand(2), true /* LoadAddrOp */);
O << "-\"L0000" << LabelNumber << "$pb\")\n";
} else if (ArgCount == 3 && ArgType[1] == PPCII::Disimm16) {
printOp(MI->getOperand(0));
O << ", ";
printImmOp(MI->getOperand(1), ArgType[1]);
O << "(";
if (MI->getOperand(2).hasAllocatedReg() &&
MI->getOperand(2).getReg() == PPC::R0)
O << "0";
else
printOp(MI->getOperand(2));
O << ")\n";
} else {
for (i = 0; i < ArgCount; ++i) {
// addi and friends
if (i == 1 && ArgCount == 3 && ArgType[2] == PPCII::Simm16 &&
MI->getOperand(1).hasAllocatedReg() &&
MI->getOperand(1).getReg() == PPC::R0) {
O << "0";
// for long branch support, bc $+8
} else if (i == 1 && ArgCount == 2 && MI->getOperand(1).isImmediate() &&
TII.isBranch(MI->getOpcode())) {
O << "$+8";
assert(8 == MI->getOperand(i).getImmedValue()
&& "branch off PC not to pc+8?");
//printOp(MI->getOperand(i));
} else if (MI->getOperand(i).isImmediate()) {
printImmOp(MI->getOperand(i), ArgType[i]);
} else {
printOp(MI->getOperand(i));
}
if (ArgCount - 1 == i)
O << "\n";
else
O << ", ";
}
}
return;
}
// SwitchSection - Switch to the specified section of the executable if we are
// not already in it!
//
static void SwitchSection(std::ostream &OS, std::string &CurSection,
const char *NewSection) {
if (CurSection != NewSection) {
CurSection = NewSection;
if (!CurSection.empty())
OS << "\t" << NewSection << "\n";
}
}
bool PowerPCAsmPrinter::doFinalization(Module &M) {
const TargetData &TD = TM.getTargetData();
std::string CurSection;
// Print out module-level global variables here.
for (Module::const_giterator I = M.gbegin(), E = M.gend(); I != E; ++I)
if (I->hasInitializer()) { // External global require no code
O << "\n\n";
std::string name = Mang->getValueName(I);
Constant *C = I->getInitializer();
unsigned Size = TD.getTypeSize(C->getType());
unsigned Align = TD.getTypeAlignment(C->getType());
if (C->isNullValue() && /* FIXME: Verify correct */
(I->hasInternalLinkage() || I->hasWeakLinkage())) {
SwitchSection(O, CurSection, ".data");
if (I->hasInternalLinkage())
O << ".lcomm " << name << "," << TD.getTypeSize(C->getType())
<< "," << (unsigned)TD.getTypeAlignment(C->getType());
else
O << ".comm " << name << "," << TD.getTypeSize(C->getType());
O << "\t\t; ";
WriteAsOperand(O, I, true, true, &M);
O << "\n";
} else {
switch (I->getLinkage()) {
case GlobalValue::LinkOnceLinkage:
O << ".section __TEXT,__textcoal_nt,coalesced,no_toc\n"
<< ".weak_definition " << name << '\n'
<< ".private_extern " << name << '\n'
<< ".section __DATA,__datacoal_nt,coalesced,no_toc\n";
LinkOnceStubs.insert(name);
break;
case GlobalValue::WeakLinkage: // FIXME: Verify correct for weak.
// Nonnull linkonce -> weak
O << "\t.weak " << name << "\n";
SwitchSection(O, CurSection, "");
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 << "\t.globl " << name << "\n";
// FALL THROUGH
case GlobalValue::InternalLinkage:
SwitchSection(O, CurSection, ".data");
break;
}
O << "\t.align " << Align << "\n";
O << name << ":\t\t\t\t; ";
WriteAsOperand(O, I, true, true, &M);
O << " = ";
WriteAsOperand(O, C, false, false, &M);
O << "\n";
emitGlobalConstant(C);
}
}
// Output stubs for dynamically-linked functions
for (std::set<std::string>::iterator i = FnStubs.begin(), e = FnStubs.end();
i != e; ++i)
{
O << ".data\n";
O << ".section __TEXT,__picsymbolstub1,symbol_stubs,pure_instructions,32\n";
O << "\t.align 2\n";
O << "L" << *i << "$stub:\n";
O << "\t.indirect_symbol " << *i << "\n";
O << "\tmflr r0\n";
O << "\tbcl 20,31,L0$" << *i << "\n";
O << "L0$" << *i << ":\n";
O << "\tmflr r11\n";
O << "\taddis r11,r11,ha16(L" << *i << "$lazy_ptr-L0$" << *i << ")\n";
O << "\tmtlr r0\n";
O << "\tlwzu r12,lo16(L" << *i << "$lazy_ptr-L0$" << *i << ")(r11)\n";
O << "\tmtctr r12\n";
O << "\tbctr\n";
O << ".data\n";
O << ".lazy_symbol_pointer\n";
O << "L" << *i << "$lazy_ptr:\n";
O << "\t.indirect_symbol " << *i << "\n";
O << "\t.long dyld_stub_binding_helper\n";
}
O << "\n";
// Output stubs for external global variables
if (GVStubs.begin() != GVStubs.end())
O << ".data\n.non_lazy_symbol_pointer\n";
for (std::set<std::string>::iterator i = GVStubs.begin(), e = GVStubs.end();
i != e; ++i) {
O << "L" << *i << "$non_lazy_ptr:\n";
O << "\t.indirect_symbol " << *i << "\n";
O << "\t.long\t0\n";
}
// Output stubs for link-once variables
if (LinkOnceStubs.begin() != LinkOnceStubs.end())
O << ".data\n.align 2\n";
for (std::set<std::string>::iterator i = LinkOnceStubs.begin(),
e = LinkOnceStubs.end(); i != e; ++i) {
O << "L" << *i << "$non_lazy_ptr:\n"
<< "\t.long\t" << *i << '\n';
}
AsmPrinter::doFinalization(M);
return false; // success
}