llvm/lib/Target/PowerPC/PPC32AsmPrinter.cpp
2004-09-04 14:51:26 +00:00

711 lines
23 KiB
C++

//===-- PowerPCAsmPrinter.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 "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/Support/Mangler.h"
#include "llvm/Support/MathExtras.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/ADT/StringExtras.h"
#include <set>
using namespace llvm;
namespace {
Statistic<> EmittedInsts("asm-printer", "Number of machine instrs printed");
struct PPC32AsmPrinter : public AsmPrinter {
std::set<std::string> FnStubs, GVStubs, LinkOnceStubs;
std::set<std::string> Strings;
PPC32AsmPrinter(std::ostream &O, TargetMachine &TM)
: AsmPrinter(O, TM), LabelNumber(0) {}
/// 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 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 printU5ImmOperand(const MachineInstr *MI, unsigned OpNo,
MVT::ValueType VT) {
unsigned char value = MI->getOperand(OpNo).getImmedValue();
assert(value <= 31 && "Invalid u5imm argument!");
O << (unsigned int)value;
}
void printU6ImmOperand(const MachineInstr *MI, unsigned OpNo,
MVT::ValueType VT) {
unsigned char value = MI->getOperand(OpNo).getImmedValue();
assert(value <= 63 && "Invalid u6imm argument!");
O << (unsigned int)value;
}
void printS16ImmOperand(const MachineInstr *MI, unsigned OpNo,
MVT::ValueType VT) {
O << (short)MI->getOperand(OpNo).getImmedValue();
}
void printU16ImmOperand(const MachineInstr *MI, unsigned OpNo,
MVT::ValueType VT) {
O << (unsigned short)MI->getOperand(OpNo).getImmedValue();
}
void printBranchOperand(const MachineInstr *MI, unsigned OpNo,
MVT::ValueType VT) {
// Branches can take an immediate operand. This is used by the branch
// selection pass to print $+8, an eight byte displacement from the PC.
if (MI->getOperand(OpNo).isImmediate()) {
O << "$+" << MI->getOperand(OpNo).getImmedValue() << '\n';
} else {
printOp(MI->getOperand(OpNo));
}
}
void printPICLabel(const MachineInstr *MI, unsigned OpNo,
MVT::ValueType VT) {
// FIXME: should probably be converted to cout.width and cout.fill
O << "\"L0000" << LabelNumber << "$pb\"\n";
O << "\"L0000" << LabelNumber << "$pb\":";
}
void printSymbolHi(const MachineInstr *MI, unsigned OpNo,
MVT::ValueType VT) {
O << "ha16(";
printOp(MI->getOperand(OpNo), true /* LoadAddrOp */);
O << "-\"L0000" << LabelNumber << "$pb\")";
}
void printSymbolLo(const MachineInstr *MI, unsigned OpNo,
MVT::ValueType VT) {
// FIXME: Because LFS, LFD, and LWZ can be used either with a s16imm or
// a lo16 of a global or constant pool operand, we must handle both here.
// this isn't a great design, but it works for now.
if (MI->getOperand(OpNo).isImmediate()) {
O << (short)MI->getOperand(OpNo).getImmedValue();
} else {
O << "lo16(";
printOp(MI->getOperand(OpNo), true /* LoadAddrOp */);
O << "-\"L0000" << LabelNumber << "$pb\")";
}
}
virtual void printConstantPool(MachineConstantPool *MCP) = 0;
virtual bool runOnMachineFunction(MachineFunction &F) = 0;
virtual bool doFinalization(Module &M) = 0;
};
//
//
struct DarwinAsmPrinter : public PPC32AsmPrinter {
DarwinAsmPrinter(std::ostream &O, TargetMachine &TM)
: PPC32AsmPrinter(O, TM) {
CommentString = ";";
GlobalPrefix = "_";
ZeroDirective = "\t.space\t"; // ".space N" emits N zeros.
Data64bitsDirective = 0; // we can't emit a 64-bit unit
AlignmentIsInBytes = false; // Alignment is by power of 2.
}
virtual const char *getPassName() const {
return "Darwin PPC Assembly Printer";
}
void printConstantPool(MachineConstantPool *MCP);
bool runOnMachineFunction(MachineFunction &F);
bool doFinalization(Module &M);
};
//
//
struct AIXAsmPrinter : public PPC32AsmPrinter {
/// Map for labels corresponding to global variables
///
std::map<const GlobalVariable*,std::string> GVToLabelMap;
AIXAsmPrinter(std::ostream &O, TargetMachine &TM)
: PPC32AsmPrinter(O, TM) {
CommentString = "#";
GlobalPrefix = "_";
ZeroDirective = "\t.space\t"; // ".space N" emits N zeros.
Data64bitsDirective = 0; // we can't emit a 64-bit unit
AlignmentIsInBytes = false; // Alignment is by power of 2.
}
virtual const char *getPassName() const {
return "AIX PPC Assembly Printer";
}
void printConstantPool(MachineConstantPool *MCP);
bool runOnMachineFunction(MachineFunction &F);
bool doInitialization(Module &M);
bool doFinalization(Module &M);
};
} // end of anonymous namespace
// 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";
}
}
/// isStringCompatible - Can we treat the specified array as a string?
/// Only if it is an array of ubytes or non-negative sbytes.
///
static bool isStringCompatible(const ConstantArray *CVA) {
const Type *ETy = cast<ArrayType>(CVA->getType())->getElementType();
if (ETy == Type::UByteTy) return true;
if (ETy != Type::SByteTy) return false;
for (unsigned i = 0; i < CVA->getNumOperands(); ++i)
if (cast<ConstantSInt>(CVA->getOperand(i))->getValue() < 0)
return false;
return true;
}
/// toOctal - Convert the low order bits of X into an octal digit.
///
static inline char toOctal(int X) {
return (X&7)+'0';
}
// Possible states while outputting ASCII strings
namespace {
enum StringSection {
None,
Alpha,
Numeric
};
}
/// SwitchStringSection - manage the changes required to output bytes as
/// characters in a string vs. numeric decimal values
///
static inline void SwitchStringSection(std::ostream &O, StringSection NewSect,
StringSection &Current) {
if (Current == None) {
if (NewSect == Alpha)
O << "\t.byte \"";
else if (NewSect == Numeric)
O << "\t.byte ";
} else if (Current == Alpha) {
if (NewSect == None)
O << "\"";
else if (NewSect == Numeric)
O << "\"\n"
<< "\t.byte ";
} else if (Current == Numeric) {
if (NewSect == Alpha)
O << '\n'
<< "\t.byte \"";
else if (NewSect == Numeric)
O << ", ";
}
Current = NewSect;
}
/// getAsCString - Return the specified array as a C compatible
/// string, only if the predicate isStringCompatible is true.
///
static void printAsCString(std::ostream &O, const ConstantArray *CVA) {
assert(isStringCompatible(CVA) && "Array is not string compatible!");
if (CVA->getNumOperands() == 0)
return;
StringSection Current = None;
for (unsigned i = 0, e = CVA->getNumOperands(); i != e; ++i) {
unsigned char C = cast<ConstantInt>(CVA->getOperand(i))->getRawValue();
if (C == '"') {
SwitchStringSection(O, Alpha, Current);
O << "\"\"";
} else if (isprint(C)) {
SwitchStringSection(O, Alpha, Current);
O << C;
} else {
SwitchStringSection(O, Numeric, Current);
O << utostr((unsigned)C);
}
}
SwitchStringSection(O, None, Current);
O << '\n';
}
/// createDarwinAsmPrinterPass - Returns a pass that prints the PPC assembly
/// code for a MachineFunction to the given output stream, in a format that the
/// Darwin assembler can deal with.
///
FunctionPass *llvm::createDarwinAsmPrinter(std::ostream &o, TargetMachine &tm) {
return new DarwinAsmPrinter(o, tm);
}
/// createAIXAsmPrinterPass - Returns a pass that prints the PPC assembly code
/// for a MachineFunction to the given output stream, in a format that the
/// AIX 5L assembler can deal with.
///
FunctionPass *llvm::createAIXAsmPrinter(std::ostream &o, TargetMachine &tm) {
return new AIXAsmPrinter(o, tm);
}
// Include the auto-generated portion of the assembly writer
#include "PowerPCGenAsmWriter.inc"
void PPC32AsmPrinter::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;
}
}
/// printMachineInstruction -- Print out a single PowerPC MI in Darwin syntax to
/// the current output stream.
///
void PPC32AsmPrinter::printMachineInstruction(const MachineInstr *MI) {
++EmittedInsts;
if (printInstruction(MI))
return; // Printer was automatically generated
assert(0 && "Unhandled instruction in asm writer!");
abort();
return;
}
/// runOnMachineFunction - This uses the printMachineInstruction()
/// method to print assembly for each instruction.
///
bool DarwinAsmPrinter::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";
emitAlignment(2);
O << "\t.globl\t" << CurrentFnName << "\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"
<< CommentString << " " << 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;
}
/// 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 DarwinAsmPrinter::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";
emitAlignment(TD.getTypeAlignmentShift(CP[i]->getType()));
O << ".CPI" << CurrentFnName << "_" << i << ":\t\t\t\t\t" << CommentString
<< *CP[i] << "\n";
emitGlobalConstant(CP[i]);
}
}
bool DarwinAsmPrinter::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.getTypeAlignmentShift(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())
<< "," << Align;
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;
}
emitAlignment(Align);
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";
emitAlignment(2);
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
}
/// runOnMachineFunction - This uses the printMachineInstruction()
/// method to print assembly for each instruction.
///
bool AIXAsmPrinter::runOnMachineFunction(MachineFunction &MF) {
CurrentFnName = MF.getFunction()->getName();
// Print out constants referenced by the function
printConstantPool(MF.getConstantPool());
// Print out header for the function.
O << "\t.csect .text[PR]\n"
<< "\t.align 2\n"
<< "\t.globl " << CurrentFnName << '\n'
<< "\t.globl ." << CurrentFnName << '\n'
<< "\t.csect " << CurrentFnName << "[DS],3\n"
<< CurrentFnName << ":\n"
<< "\t.llong ." << CurrentFnName << ", TOC[tc0], 0\n"
<< "\t.csect .text[PR]\n"
<< '.' << 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;
O << "LT.." << CurrentFnName << ":\n"
<< "\t.long 0\n"
<< "\t.byte 0,0,32,65,128,0,0,0\n"
<< "\t.long LT.." << CurrentFnName << "-." << CurrentFnName << '\n'
<< "\t.short 3\n"
<< "\t.byte \"" << CurrentFnName << "\"\n"
<< "\t.align 2\n";
// We didn't modify anything.
return false;
}
/// 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 AIXAsmPrinter::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]);
}
}
bool AIXAsmPrinter::doInitialization(Module &M) {
const TargetData &TD = TM.getTargetData();
std::string CurSection;
O << "\t.machine \"ppc64\"\n"
<< "\t.toc\n"
<< "\t.csect .text[PR]\n";
// Print out module-level global variables
for (Module::const_giterator I = M.gbegin(), E = M.gend(); I != E; ++I) {
if (!I->hasInitializer())
continue;
std::string Name = I->getName();
Constant *C = I->getInitializer();
// N.B.: We are defaulting to writable strings
if (I->hasExternalLinkage()) {
O << "\t.globl " << Name << '\n'
<< "\t.csect .data[RW],3\n";
} else {
O << "\t.csect _global.rw_c[RW],3\n";
}
O << Name << ":\n";
emitGlobalConstant(C);
}
// Output labels for globals
if (M.gbegin() != M.gend()) O << "\t.toc\n";
for (Module::const_giterator I = M.gbegin(), E = M.gend(); I != E; ++I) {
const GlobalVariable *GV = I;
// Do not output labels for unused variables
if (GV->isExternal() && GV->use_begin() == GV->use_end())
continue;
std::string Name = GV->getName();
std::string Label = "LC.." + utostr(LabelNumber++);
GVToLabelMap[GV] = Label;
O << Label << ":\n"
<< "\t.tc " << Name << "[TC]," << Name;
if (GV->isExternal()) O << "[RW]";
O << '\n';
}
Mang = new Mangler(M, ".");
return false; // success
}
bool AIXAsmPrinter::doFinalization(Module &M) {
const TargetData &TD = TM.getTargetData();
// Print out module-level global variables
for (Module::const_giterator I = M.gbegin(), E = M.gend(); I != E; ++I) {
if (I->hasInitializer() || I->hasExternalLinkage())
continue;
std::string Name = I->getName();
if (I->hasInternalLinkage()) {
O << "\t.lcomm " << Name << ",16,_global.bss_c";
} else {
O << "\t.comm " << Name << "," << TD.getTypeSize(I->getType())
<< "," << log2((unsigned)TD.getTypeAlignment(I->getType()));
}
O << "\t\t# ";
WriteAsOperand(O, I, true, true, &M);
O << "\n";
}
O << "_section_.text:\n"
<< "\t.csect .data[RW],3\n"
<< "\t.llong _section_.text\n";
delete Mang;
return false; // success
}