llvm-6502/lib/Target/PowerPC/PPCAsmPrinter.cpp

1143 lines
38 KiB
C++

//===-- PPCAsmPrinter.cpp - Print machine instrs to PowerPC assembly --------=//
//
// 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 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 "PPC.h"
#include "PPCPredicates.h"
#include "PPCTargetMachine.h"
#include "PPCSubtarget.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/DwarfWriter.h"
#include "llvm/CodeGen/MachineModuleInfo.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/Support/Mangler.h"
#include "llvm/Support/MathExtras.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Target/TargetAsmInfo.h"
#include "llvm/Target/TargetRegisterInfo.h"
#include "llvm/Target/TargetInstrInfo.h"
#include "llvm/Target/TargetOptions.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/ADT/StringExtras.h"
#include <set>
using namespace llvm;
STATISTIC(EmittedInsts, "Number of machine instrs printed");
namespace {
struct VISIBILITY_HIDDEN PPCAsmPrinter : public AsmPrinter {
std::set<std::string> FnStubs, GVStubs;
const PPCSubtarget &Subtarget;
PPCAsmPrinter(std::ostream &O, TargetMachine &TM, const TargetAsmInfo *T)
: AsmPrinter(O, TM, T), Subtarget(TM.getSubtarget<PPCSubtarget>()) {
}
virtual const char *getPassName() const {
return "PowerPC Assembly Printer";
}
PPCTargetMachine &getTM() {
return static_cast<PPCTargetMachine&>(TM);
}
unsigned enumRegToMachineReg(unsigned enumReg) {
switch (enumReg) {
default: assert(0 && "Unhandled register!"); break;
case PPC::CR0: return 0;
case PPC::CR1: return 1;
case PPC::CR2: return 2;
case PPC::CR3: return 3;
case PPC::CR4: return 4;
case PPC::CR5: return 5;
case PPC::CR6: return 6;
case PPC::CR7: return 7;
}
abort();
}
/// 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);
/// stripRegisterPrefix - This method strips the character prefix from a
/// register name so that only the number is left. Used by for linux asm.
const char *stripRegisterPrefix(const char *RegName) {
switch (RegName[0]) {
case 'r':
case 'f':
case 'v': return RegName + 1;
case 'c': if (RegName[1] == 'r') return RegName + 2;
}
return RegName;
}
/// printRegister - Print register according to target requirements.
///
void printRegister(const MachineOperand &MO, bool R0AsZero) {
unsigned RegNo = MO.getReg();
assert(TargetRegisterInfo::isPhysicalRegister(RegNo) && "Not physreg??");
// If we should use 0 for R0.
if (R0AsZero && RegNo == PPC::R0) {
O << "0";
return;
}
const char *RegName = TM.getRegisterInfo()->get(RegNo).AsmName;
// Linux assembler (Others?) does not take register mnemonics.
// FIXME - What about special registers used in mfspr/mtspr?
if (!Subtarget.isDarwin()) RegName = stripRegisterPrefix(RegName);
O << RegName;
}
void printOperand(const MachineInstr *MI, unsigned OpNo) {
const MachineOperand &MO = MI->getOperand(OpNo);
if (MO.isRegister()) {
printRegister(MO, false);
} else if (MO.isImmediate()) {
O << MO.getImm();
} else {
printOp(MO);
}
}
bool PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
unsigned AsmVariant, const char *ExtraCode);
bool PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo,
unsigned AsmVariant, const char *ExtraCode);
void printS5ImmOperand(const MachineInstr *MI, unsigned OpNo) {
char value = MI->getOperand(OpNo).getImm();
value = (value << (32-5)) >> (32-5);
O << (int)value;
}
void printU5ImmOperand(const MachineInstr *MI, unsigned OpNo) {
unsigned char value = MI->getOperand(OpNo).getImm();
assert(value <= 31 && "Invalid u5imm argument!");
O << (unsigned int)value;
}
void printU6ImmOperand(const MachineInstr *MI, unsigned OpNo) {
unsigned char value = MI->getOperand(OpNo).getImm();
assert(value <= 63 && "Invalid u6imm argument!");
O << (unsigned int)value;
}
void printS16ImmOperand(const MachineInstr *MI, unsigned OpNo) {
O << (short)MI->getOperand(OpNo).getImm();
}
void printU16ImmOperand(const MachineInstr *MI, unsigned OpNo) {
O << (unsigned short)MI->getOperand(OpNo).getImm();
}
void printS16X4ImmOperand(const MachineInstr *MI, unsigned OpNo) {
if (MI->getOperand(OpNo).isImmediate()) {
O << (short)(MI->getOperand(OpNo).getImm()*4);
} else {
O << "lo16(";
printOp(MI->getOperand(OpNo));
if (TM.getRelocationModel() == Reloc::PIC_)
O << "-\"L" << getFunctionNumber() << "$pb\")";
else
O << ')';
}
}
void printBranchOperand(const MachineInstr *MI, unsigned OpNo) {
// 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).getImm()*4;
} else {
printOp(MI->getOperand(OpNo));
}
}
void printCallOperand(const MachineInstr *MI, unsigned OpNo) {
const MachineOperand &MO = MI->getOperand(OpNo);
if (TM.getRelocationModel() != Reloc::Static) {
if (MO.getType() == MachineOperand::MO_GlobalAddress) {
GlobalValue *GV = MO.getGlobal();
if (((GV->isDeclaration() || GV->hasWeakLinkage() ||
GV->hasLinkOnceLinkage()))) {
// Dynamically-resolved functions need a stub for the function.
std::string Name = Mang->getValueName(GV);
FnStubs.insert(Name);
O << "L" << Name << "$stub";
if (GV->hasExternalWeakLinkage())
ExtWeakSymbols.insert(GV);
return;
}
}
if (MO.getType() == MachineOperand::MO_ExternalSymbol) {
std::string Name(TAI->getGlobalPrefix()); Name += MO.getSymbolName();
FnStubs.insert(Name);
O << "L" << Name << "$stub";
return;
}
}
printOp(MI->getOperand(OpNo));
}
void printAbsAddrOperand(const MachineInstr *MI, unsigned OpNo) {
O << (int)MI->getOperand(OpNo).getImm()*4;
}
void printPICLabel(const MachineInstr *MI, unsigned OpNo) {
O << "\"L" << getFunctionNumber() << "$pb\"\n";
O << "\"L" << getFunctionNumber() << "$pb\":";
}
void printSymbolHi(const MachineInstr *MI, unsigned OpNo) {
if (MI->getOperand(OpNo).isImmediate()) {
printS16ImmOperand(MI, OpNo);
} else {
if (Subtarget.isDarwin()) O << "ha16(";
printOp(MI->getOperand(OpNo));
if (TM.getRelocationModel() == Reloc::PIC_)
O << "-\"L" << getFunctionNumber() << "$pb\"";
if (Subtarget.isDarwin())
O << ')';
else
O << "@ha";
}
}
void printSymbolLo(const MachineInstr *MI, unsigned OpNo) {
if (MI->getOperand(OpNo).isImmediate()) {
printS16ImmOperand(MI, OpNo);
} else {
if (Subtarget.isDarwin()) O << "lo16(";
printOp(MI->getOperand(OpNo));
if (TM.getRelocationModel() == Reloc::PIC_)
O << "-\"L" << getFunctionNumber() << "$pb\"";
if (Subtarget.isDarwin())
O << ')';
else
O << "@l";
}
}
void printcrbitm(const MachineInstr *MI, unsigned OpNo) {
unsigned CCReg = MI->getOperand(OpNo).getReg();
unsigned RegNo = enumRegToMachineReg(CCReg);
O << (0x80 >> RegNo);
}
// The new addressing mode printers.
void printMemRegImm(const MachineInstr *MI, unsigned OpNo) {
printSymbolLo(MI, OpNo);
O << '(';
if (MI->getOperand(OpNo+1).isRegister() &&
MI->getOperand(OpNo+1).getReg() == PPC::R0)
O << "0";
else
printOperand(MI, OpNo+1);
O << ')';
}
void printMemRegImmShifted(const MachineInstr *MI, unsigned OpNo) {
if (MI->getOperand(OpNo).isImmediate())
printS16X4ImmOperand(MI, OpNo);
else
printSymbolLo(MI, OpNo);
O << '(';
if (MI->getOperand(OpNo+1).isRegister() &&
MI->getOperand(OpNo+1).getReg() == PPC::R0)
O << "0";
else
printOperand(MI, OpNo+1);
O << ')';
}
void printMemRegReg(const MachineInstr *MI, unsigned OpNo) {
// When used as the base register, r0 reads constant zero rather than
// the value contained in the register. For this reason, the darwin
// assembler requires that we print r0 as 0 (no r) when used as the base.
const MachineOperand &MO = MI->getOperand(OpNo);
printRegister(MO, true);
O << ", ";
printOperand(MI, OpNo+1);
}
void printPredicateOperand(const MachineInstr *MI, unsigned OpNo,
const char *Modifier);
virtual bool runOnMachineFunction(MachineFunction &F) = 0;
virtual bool doFinalization(Module &M) = 0;
virtual void EmitExternalGlobal(const GlobalVariable *GV);
};
/// LinuxAsmPrinter - PowerPC assembly printer, customized for Linux
struct VISIBILITY_HIDDEN LinuxAsmPrinter : public PPCAsmPrinter {
DwarfWriter DW;
LinuxAsmPrinter(std::ostream &O, PPCTargetMachine &TM,
const TargetAsmInfo *T)
: PPCAsmPrinter(O, TM, T), DW(O, this, T) {
}
virtual const char *getPassName() const {
return "Linux PPC Assembly Printer";
}
bool runOnMachineFunction(MachineFunction &F);
bool doInitialization(Module &M);
bool doFinalization(Module &M);
void getAnalysisUsage(AnalysisUsage &AU) const {
AU.setPreservesAll();
AU.addRequired<MachineModuleInfo>();
PPCAsmPrinter::getAnalysisUsage(AU);
}
/// getSectionForFunction - Return the section that we should emit the
/// specified function body into.
virtual std::string getSectionForFunction(const Function &F) const;
};
/// DarwinAsmPrinter - PowerPC assembly printer, customized for Darwin/Mac OS
/// X
struct VISIBILITY_HIDDEN DarwinAsmPrinter : public PPCAsmPrinter {
DwarfWriter DW;
MachineModuleInfo *MMI;
DarwinAsmPrinter(std::ostream &O, PPCTargetMachine &TM,
const TargetAsmInfo *T)
: PPCAsmPrinter(O, TM, T), DW(O, this, T), MMI(0) {
}
virtual const char *getPassName() const {
return "Darwin PPC Assembly Printer";
}
bool runOnMachineFunction(MachineFunction &F);
bool doInitialization(Module &M);
bool doFinalization(Module &M);
void getAnalysisUsage(AnalysisUsage &AU) const {
AU.setPreservesAll();
AU.addRequired<MachineModuleInfo>();
PPCAsmPrinter::getAnalysisUsage(AU);
}
/// getSectionForFunction - Return the section that we should emit the
/// specified function body into.
virtual std::string getSectionForFunction(const Function &F) const;
};
} // end of anonymous namespace
// Include the auto-generated portion of the assembly writer
#include "PPCGenAsmWriter.inc"
void PPCAsmPrinter::printOp(const MachineOperand &MO) {
switch (MO.getType()) {
case MachineOperand::MO_Immediate:
cerr << "printOp() does not handle immediate values\n";
abort();
return;
case MachineOperand::MO_MachineBasicBlock:
printBasicBlockLabel(MO.getMBB());
return;
case MachineOperand::MO_JumpTableIndex:
O << TAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber()
<< '_' << MO.getIndex();
// FIXME: PIC relocation model
return;
case MachineOperand::MO_ConstantPoolIndex:
O << TAI->getPrivateGlobalPrefix() << "CPI" << getFunctionNumber()
<< '_' << MO.getIndex();
return;
case MachineOperand::MO_ExternalSymbol:
// Computing the address of an external symbol, not calling it.
if (TM.getRelocationModel() != Reloc::Static) {
std::string Name(TAI->getGlobalPrefix()); Name += MO.getSymbolName();
GVStubs.insert(Name);
O << "L" << Name << "$non_lazy_ptr";
return;
}
O << TAI->getGlobalPrefix() << MO.getSymbolName();
return;
case MachineOperand::MO_GlobalAddress: {
// Computing the address of a global symbol, not calling it.
GlobalValue *GV = MO.getGlobal();
std::string Name = Mang->getValueName(GV);
// External or weakly linked global variables need non-lazily-resolved stubs
if (TM.getRelocationModel() != Reloc::Static) {
if (((GV->isDeclaration() || GV->hasWeakLinkage() ||
GV->hasLinkOnceLinkage()))) {
GVStubs.insert(Name);
O << "L" << Name << "$non_lazy_ptr";
return;
}
}
O << Name;
if (MO.getOffset() > 0)
O << "+" << MO.getOffset();
else if (MO.getOffset() < 0)
O << MO.getOffset();
if (GV->hasExternalWeakLinkage())
ExtWeakSymbols.insert(GV);
return;
}
default:
O << "<unknown operand type: " << MO.getType() << ">";
return;
}
}
/// EmitExternalGlobal - In this case we need to use the indirect symbol.
///
void PPCAsmPrinter::EmitExternalGlobal(const GlobalVariable *GV) {
std::string Name = getGlobalLinkName(GV);
if (TM.getRelocationModel() != Reloc::Static) {
GVStubs.insert(Name);
O << "L" << Name << "$non_lazy_ptr";
return;
}
O << Name;
}
/// PrintAsmOperand - Print out an operand for an inline asm expression.
///
bool PPCAsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
unsigned AsmVariant,
const char *ExtraCode) {
// Does this asm operand have a single letter operand modifier?
if (ExtraCode && ExtraCode[0]) {
if (ExtraCode[1] != 0) return true; // Unknown modifier.
switch (ExtraCode[0]) {
default: return true; // Unknown modifier.
case 'c': // Don't print "$" before a global var name or constant.
// PPC never has a prefix.
printOperand(MI, OpNo);
return false;
case 'L': // Write second word of DImode reference.
// Verify that this operand has two consecutive registers.
if (!MI->getOperand(OpNo).isRegister() ||
OpNo+1 == MI->getNumOperands() ||
!MI->getOperand(OpNo+1).isRegister())
return true;
++OpNo; // Return the high-part.
break;
case 'I':
// Write 'i' if an integer constant, otherwise nothing. Used to print
// addi vs add, etc.
if (MI->getOperand(OpNo).isImmediate())
O << "i";
return false;
}
}
printOperand(MI, OpNo);
return false;
}
bool PPCAsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo,
unsigned AsmVariant,
const char *ExtraCode) {
if (ExtraCode && ExtraCode[0])
return true; // Unknown modifier.
if (MI->getOperand(OpNo).isRegister())
printMemRegReg(MI, OpNo);
else
printMemRegImm(MI, OpNo);
return false;
}
void PPCAsmPrinter::printPredicateOperand(const MachineInstr *MI, unsigned OpNo,
const char *Modifier) {
assert(Modifier && "Must specify 'cc' or 'reg' as predicate op modifier!");
unsigned Code = MI->getOperand(OpNo).getImm();
if (!strcmp(Modifier, "cc")) {
switch ((PPC::Predicate)Code) {
case PPC::PRED_ALWAYS: return; // Don't print anything for always.
case PPC::PRED_LT: O << "lt"; return;
case PPC::PRED_LE: O << "le"; return;
case PPC::PRED_EQ: O << "eq"; return;
case PPC::PRED_GE: O << "ge"; return;
case PPC::PRED_GT: O << "gt"; return;
case PPC::PRED_NE: O << "ne"; return;
case PPC::PRED_UN: O << "un"; return;
case PPC::PRED_NU: O << "nu"; return;
}
} else {
assert(!strcmp(Modifier, "reg") &&
"Need to specify 'cc' or 'reg' as predicate op modifier!");
// Don't print the register for 'always'.
if (Code == PPC::PRED_ALWAYS) return;
printOperand(MI, OpNo+1);
}
}
/// printMachineInstruction -- Print out a single PowerPC MI in Darwin syntax to
/// the current output stream.
///
void PPCAsmPrinter::printMachineInstruction(const MachineInstr *MI) {
++EmittedInsts;
// Check for slwi/srwi mnemonics.
if (MI->getOpcode() == PPC::RLWINM) {
bool FoundMnemonic = false;
unsigned char SH = MI->getOperand(2).getImm();
unsigned char MB = MI->getOperand(3).getImm();
unsigned char ME = MI->getOperand(4).getImm();
if (SH <= 31 && MB == 0 && ME == (31-SH)) {
O << "\tslwi "; FoundMnemonic = true;
}
if (SH <= 31 && MB == (32-SH) && ME == 31) {
O << "\tsrwi "; FoundMnemonic = true;
SH = 32-SH;
}
if (FoundMnemonic) {
printOperand(MI, 0);
O << ", ";
printOperand(MI, 1);
O << ", " << (unsigned int)SH << "\n";
return;
}
} else if (MI->getOpcode() == PPC::OR || MI->getOpcode() == PPC::OR8) {
if (MI->getOperand(1).getReg() == MI->getOperand(2).getReg()) {
O << "\tmr ";
printOperand(MI, 0);
O << ", ";
printOperand(MI, 1);
O << "\n";
return;
}
} else if (MI->getOpcode() == PPC::RLDICR) {
unsigned char SH = MI->getOperand(2).getImm();
unsigned char ME = MI->getOperand(3).getImm();
// rldicr RA, RS, SH, 63-SH == sldi RA, RS, SH
if (63-SH == ME) {
O << "\tsldi ";
printOperand(MI, 0);
O << ", ";
printOperand(MI, 1);
O << ", " << (unsigned int)SH << "\n";
return;
}
}
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 LinuxAsmPrinter::runOnMachineFunction(MachineFunction &MF) {
DW.SetModuleInfo(&getAnalysis<MachineModuleInfo>());
SetupMachineFunction(MF);
O << "\n\n";
// Print out constants referenced by the function
EmitConstantPool(MF.getConstantPool());
// Print out labels for the function.
const Function *F = MF.getFunction();
SwitchToTextSection(getSectionForFunction(*F).c_str(), F);
switch (F->getLinkage()) {
default: assert(0 && "Unknown linkage type!");
case Function::InternalLinkage: // Symbols default to internal.
break;
case Function::ExternalLinkage:
O << "\t.global\t" << CurrentFnName << '\n'
<< "\t.type\t" << CurrentFnName << ", @function\n";
break;
case Function::WeakLinkage:
case Function::LinkOnceLinkage:
O << "\t.global\t" << CurrentFnName << '\n';
O << "\t.weak\t" << CurrentFnName << '\n';
break;
}
if (F->hasHiddenVisibility())
if (const char *Directive = TAI->getHiddenDirective())
O << Directive << CurrentFnName << "\n";
EmitAlignment(2, F);
O << CurrentFnName << ":\n";
// Emit pre-function debug information.
DW.BeginFunction(&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, true);
O << '\n';
}
for (MachineBasicBlock::const_iterator II = I->begin(), E = I->end();
II != E; ++II) {
// Print the assembly for the instruction.
printMachineInstruction(II);
}
}
O << "\t.size\t" << CurrentFnName << ",.-" << CurrentFnName << "\n";
// Print out jump tables referenced by the function.
EmitJumpTableInfo(MF.getJumpTableInfo(), MF);
// Emit post-function debug information.
DW.EndFunction();
// We didn't modify anything.
return false;
}
bool LinuxAsmPrinter::doInitialization(Module &M) {
bool Result = AsmPrinter::doInitialization(M);
// GNU as handles section names wrapped in quotes
Mang->setUseQuotes(true);
SwitchToTextSection(TAI->getTextSection());
// Emit initial debug information.
DW.BeginModule(&M);
return Result;
}
/// PrintUnmangledNameSafely - Print out the printable characters in the name.
/// Don't print things like \n or \0.
static void PrintUnmangledNameSafely(const Value *V, std::ostream &OS) {
for (const char *Name = V->getNameStart(), *E = Name+V->getNameLen();
Name != E; ++Name)
if (isprint(*Name))
OS << *Name;
}
bool LinuxAsmPrinter::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) {
if (!I->hasInitializer()) continue; // External global require no code
// Check to see if this is a special global used by LLVM, if so, emit it.
if (EmitSpecialLLVMGlobal(I))
continue;
std::string name = Mang->getValueName(I);
if (I->hasHiddenVisibility())
if (const char *Directive = TAI->getHiddenDirective())
O << Directive << name << "\n";
Constant *C = I->getInitializer();
unsigned Size = TD->getABITypeSize(C->getType());
unsigned Align = TD->getPreferredAlignmentLog(I);
if (C->isNullValue() && /* FIXME: Verify correct */
!I->hasSection() &&
(I->hasInternalLinkage() || I->hasWeakLinkage() ||
I->hasLinkOnceLinkage() || I->hasExternalLinkage())) {
if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
if (I->hasExternalLinkage()) {
O << "\t.global " << name << '\n';
O << "\t.type " << name << ", @object\n";
if (TAI->getBSSSection())
SwitchToDataSection(TAI->getBSSSection(), I);
O << name << ":\n";
O << "\t.zero " << Size << "\n";
} else if (I->hasInternalLinkage()) {
SwitchToDataSection("\t.data", I);
O << TAI->getLCOMMDirective() << name << "," << Size;
} else {
SwitchToDataSection("\t.data", I);
O << ".comm " << name << "," << Size;
}
O << "\t\t" << TAI->getCommentString() << " '";
PrintUnmangledNameSafely(I, O);
O << "'\n";
} else {
switch (I->getLinkage()) {
case GlobalValue::LinkOnceLinkage:
case GlobalValue::WeakLinkage:
O << "\t.global " << name << '\n'
<< "\t.type " << name << ", @object\n"
<< "\t.weak " << name << '\n';
SwitchToDataSection("\t.data", I);
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.global " << name << "\n"
<< "\t.type " << name << ", @object\n";
// FALL THROUGH
case GlobalValue::InternalLinkage:
if (I->isConstant()) {
const ConstantArray *CVA = dyn_cast<ConstantArray>(C);
if (TAI->getCStringSection() && CVA && CVA->isCString()) {
SwitchToDataSection(TAI->getCStringSection(), I);
break;
}
}
// FIXME: special handling for ".ctors" & ".dtors" sections
if (I->hasSection() &&
(I->getSection() == ".ctors" ||
I->getSection() == ".dtors")) {
std::string SectionName = ".section " + I->getSection()
+ ",\"aw\",@progbits";
SwitchToDataSection(SectionName.c_str());
} else {
if (I->isConstant() && TAI->getReadOnlySection())
SwitchToDataSection(TAI->getReadOnlySection(), I);
else
SwitchToDataSection(TAI->getDataSection(), I);
}
break;
default:
cerr << "Unknown linkage type!";
abort();
}
EmitAlignment(Align, I);
O << name << ":\t\t\t\t" << TAI->getCommentString() << " '";
PrintUnmangledNameSafely(I, O);
O << "'\n";
// If the initializer is a extern weak symbol, remember to emit the weak
// reference!
if (const GlobalValue *GV = dyn_cast<GlobalValue>(C))
if (GV->hasExternalWeakLinkage())
ExtWeakSymbols.insert(GV);
EmitGlobalConstant(C);
O << '\n';
}
}
// TODO
// Emit initial debug information.
DW.EndModule();
return AsmPrinter::doFinalization(M);
}
std::string LinuxAsmPrinter::getSectionForFunction(const Function &F) const {
switch (F.getLinkage()) {
default: assert(0 && "Unknown linkage type!");
case Function::ExternalLinkage:
case Function::InternalLinkage: return TAI->getTextSection();
case Function::WeakLinkage:
case Function::LinkOnceLinkage:
return ".text";
}
}
std::string DarwinAsmPrinter::getSectionForFunction(const Function &F) const {
switch (F.getLinkage()) {
default: assert(0 && "Unknown linkage type!");
case Function::ExternalLinkage:
case Function::InternalLinkage: return TAI->getTextSection();
case Function::WeakLinkage:
case Function::LinkOnceLinkage:
return "\t.section __TEXT,__textcoal_nt,coalesced,pure_instructions";
}
}
/// runOnMachineFunction - This uses the printMachineInstruction()
/// method to print assembly for each instruction.
///
bool DarwinAsmPrinter::runOnMachineFunction(MachineFunction &MF) {
// We need this for Personality functions.
MMI = &getAnalysis<MachineModuleInfo>();
DW.SetModuleInfo(MMI);
SetupMachineFunction(MF);
O << "\n\n";
// Print out constants referenced by the function
EmitConstantPool(MF.getConstantPool());
// Print out labels for the function.
const Function *F = MF.getFunction();
SwitchToTextSection(getSectionForFunction(*F).c_str(), F);
switch (F->getLinkage()) {
default: assert(0 && "Unknown linkage type!");
case Function::InternalLinkage: // Symbols default to internal.
break;
case Function::ExternalLinkage:
O << "\t.globl\t" << CurrentFnName << "\n";
break;
case Function::WeakLinkage:
case Function::LinkOnceLinkage:
O << "\t.globl\t" << CurrentFnName << "\n";
O << "\t.weak_definition\t" << CurrentFnName << "\n";
break;
}
if (F->hasHiddenVisibility())
if (const char *Directive = TAI->getHiddenDirective())
O << Directive << CurrentFnName << "\n";
EmitAlignment(4, F);
O << CurrentFnName << ":\n";
// Emit pre-function debug information.
DW.BeginFunction(&MF);
// If the function is empty, then we need to emit *something*. Otherwise, the
// function's label might be associated with something that it wasn't meant to
// be associated with. We emit a noop in this situation.
MachineFunction::iterator I = MF.begin();
if (++I == MF.end() && MF.front().empty())
O << "\tnop\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.
if (I != MF.begin()) {
printBasicBlockLabel(I, true, true);
O << '\n';
}
for (MachineBasicBlock::const_iterator II = I->begin(), IE = I->end();
II != IE; ++II) {
// Print the assembly for the instruction.
printMachineInstruction(II);
}
}
// Print out jump tables referenced by the function.
EmitJumpTableInfo(MF.getJumpTableInfo(), MF);
// Emit post-function debug information.
DW.EndFunction();
// We didn't modify anything.
return false;
}
bool DarwinAsmPrinter::doInitialization(Module &M) {
static const char *CPUDirectives[] = {
"",
"ppc",
"ppc601",
"ppc602",
"ppc603",
"ppc7400",
"ppc750",
"ppc970",
"ppc64"
};
unsigned Directive = Subtarget.getDarwinDirective();
if (Subtarget.isGigaProcessor() && Directive < PPC::DIR_970)
Directive = PPC::DIR_970;
if (Subtarget.hasAltivec() && Directive < PPC::DIR_7400)
Directive = PPC::DIR_7400;
if (Subtarget.isPPC64() && Directive < PPC::DIR_970)
Directive = PPC::DIR_64;
assert(Directive <= PPC::DIR_64 && "Directive out of range.");
O << "\t.machine " << CPUDirectives[Directive] << "\n";
bool Result = AsmPrinter::doInitialization(M);
// Darwin wants symbols to be quoted if they have complex names.
Mang->setUseQuotes(true);
// Prime text sections so they are adjacent. This reduces the likelihood a
// large data or debug section causes a branch to exceed 16M limit.
SwitchToTextSection("\t.section __TEXT,__textcoal_nt,coalesced,"
"pure_instructions");
if (TM.getRelocationModel() == Reloc::PIC_) {
SwitchToTextSection("\t.section __TEXT,__picsymbolstub1,symbol_stubs,"
"pure_instructions,32");
} else if (TM.getRelocationModel() == Reloc::DynamicNoPIC) {
SwitchToTextSection("\t.section __TEXT,__symbol_stub1,symbol_stubs,"
"pure_instructions,16");
}
SwitchToTextSection(TAI->getTextSection());
// Emit initial debug information.
DW.BeginModule(&M);
return Result;
}
bool DarwinAsmPrinter::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) {
if (!I->hasInitializer()) continue; // External global require no code
// Check to see if this is a special global used by LLVM, if so, emit it.
if (EmitSpecialLLVMGlobal(I)) {
if (TM.getRelocationModel() == Reloc::Static) {
if (I->getName() == "llvm.global_ctors")
O << ".reference .constructors_used\n";
else if (I->getName() == "llvm.global_dtors")
O << ".reference .destructors_used\n";
}
continue;
}
std::string name = Mang->getValueName(I);
if (I->hasHiddenVisibility())
if (const char *Directive = TAI->getHiddenDirective())
O << Directive << name << "\n";
Constant *C = I->getInitializer();
const Type *Type = C->getType();
unsigned Size = TD->getABITypeSize(Type);
unsigned Align = TD->getPreferredAlignmentLog(I);
if (C->isNullValue() && /* FIXME: Verify correct */
!I->hasSection() &&
(I->hasInternalLinkage() || I->hasWeakLinkage() ||
I->hasLinkOnceLinkage() || I->hasExternalLinkage())) {
if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
if (I->hasExternalLinkage()) {
O << "\t.globl " << name << '\n';
O << "\t.zerofill __DATA, __common, " << name << ", "
<< Size << ", " << Align;
} else if (I->hasInternalLinkage()) {
SwitchToDataSection("\t.data", I);
O << TAI->getLCOMMDirective() << name << "," << Size << "," << Align;
} else {
SwitchToDataSection("\t.data", I);
O << ".comm " << name << "," << Size;
// Darwin 9 and above support aligned common data.
if (Subtarget.isDarwin9())
O << "," << Align;
}
O << "\t\t" << TAI->getCommentString() << " '";
PrintUnmangledNameSafely(I, O);
O << "'\n";
} else {
switch (I->getLinkage()) {
case GlobalValue::LinkOnceLinkage:
case GlobalValue::WeakLinkage:
O << "\t.globl " << name << '\n'
<< "\t.weak_definition " << name << '\n';
SwitchToDataSection("\t.section __DATA,__datacoal_nt,coalesced", I);
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:
if (I->isConstant()) {
const ConstantArray *CVA = dyn_cast<ConstantArray>(C);
if (TAI->getCStringSection() && CVA && CVA->isCString()) {
SwitchToDataSection(TAI->getCStringSection(), I);
break;
}
}
if (I->hasSection()) {
// Honor all section names on Darwin; ObjC uses this
std::string SectionName = ".section " + I->getSection();
SwitchToDataSection(SectionName.c_str());
} else if (!I->isConstant())
SwitchToDataSection(TAI->getDataSection(), I);
else {
// Read-only data.
bool HasReloc = C->ContainsRelocations();
if (HasReloc &&
TM.getRelocationModel() != Reloc::Static)
SwitchToDataSection("\t.const_data\n");
else if (!HasReloc && Size == 4 &&
TAI->getFourByteConstantSection())
SwitchToDataSection(TAI->getFourByteConstantSection(), I);
else if (!HasReloc && Size == 8 &&
TAI->getEightByteConstantSection())
SwitchToDataSection(TAI->getEightByteConstantSection(), I);
else if (!HasReloc && Size == 16 &&
TAI->getSixteenByteConstantSection())
SwitchToDataSection(TAI->getSixteenByteConstantSection(), I);
else if (TAI->getReadOnlySection())
SwitchToDataSection(TAI->getReadOnlySection(), I);
else
SwitchToDataSection(TAI->getDataSection(), I);
}
break;
default:
cerr << "Unknown linkage type!";
abort();
}
EmitAlignment(Align, I);
O << name << ":\t\t\t\t" << TAI->getCommentString() << " '";
PrintUnmangledNameSafely(I, O);
O << "'\n";
// If the initializer is a extern weak symbol, remember to emit the weak
// reference!
if (const GlobalValue *GV = dyn_cast<GlobalValue>(C))
if (GV->hasExternalWeakLinkage())
ExtWeakSymbols.insert(GV);
EmitGlobalConstant(C);
O << '\n';
}
}
bool isPPC64 = TD->getPointerSizeInBits() == 64;
// Output stubs for dynamically-linked functions
if (TM.getRelocationModel() == Reloc::PIC_) {
for (std::set<std::string>::iterator i = FnStubs.begin(), e = FnStubs.end();
i != e; ++i) {
SwitchToTextSection("\t.section __TEXT,__picsymbolstub1,symbol_stubs,"
"pure_instructions,32");
EmitAlignment(4);
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$" << *i << ")\n";
O << "\tmtlr r0\n";
if (isPPC64)
O << "\tldu r12,lo16(L" << *i << "$lazy_ptr-L0$" << *i << ")(r11)\n";
else
O << "\tlwzu r12,lo16(L" << *i << "$lazy_ptr-L0$" << *i << ")(r11)\n";
O << "\tmtctr r12\n";
O << "\tbctr\n";
SwitchToDataSection(".lazy_symbol_pointer");
O << "L" << *i << "$lazy_ptr:\n";
O << "\t.indirect_symbol " << *i << "\n";
if (isPPC64)
O << "\t.quad dyld_stub_binding_helper\n";
else
O << "\t.long dyld_stub_binding_helper\n";
}
} else {
for (std::set<std::string>::iterator i = FnStubs.begin(), e = FnStubs.end();
i != e; ++i) {
SwitchToTextSection("\t.section __TEXT,__symbol_stub1,symbol_stubs,"
"pure_instructions,16");
EmitAlignment(4);
O << "L" << *i << "$stub:\n";
O << "\t.indirect_symbol " << *i << "\n";
O << "\tlis r11,ha16(L" << *i << "$lazy_ptr)\n";
if (isPPC64)
O << "\tldu r12,lo16(L" << *i << "$lazy_ptr)(r11)\n";
else
O << "\tlwzu r12,lo16(L" << *i << "$lazy_ptr)(r11)\n";
O << "\tmtctr r12\n";
O << "\tbctr\n";
SwitchToDataSection(".lazy_symbol_pointer");
O << "L" << *i << "$lazy_ptr:\n";
O << "\t.indirect_symbol " << *i << "\n";
if (isPPC64)
O << "\t.quad dyld_stub_binding_helper\n";
else
O << "\t.long dyld_stub_binding_helper\n";
}
}
O << "\n";
if (ExceptionHandling && TAI->doesSupportExceptionHandling() && MMI) {
// Add the (possibly multiple) personalities to the set of global values.
const std::vector<Function *>& Personalities = MMI->getPersonalities();
for (std::vector<Function *>::const_iterator I = Personalities.begin(),
E = Personalities.end(); I != E; ++I)
if (*I) GVStubs.insert("_" + (*I)->getName());
}
// Output stubs for external and common global variables.
if (!GVStubs.empty()) {
SwitchToDataSection(".non_lazy_symbol_pointer");
for (std::set<std::string>::iterator I = GVStubs.begin(),
E = GVStubs.end(); I != E; ++I) {
O << "L" << *I << "$non_lazy_ptr:\n";
O << "\t.indirect_symbol " << *I << "\n";
if (isPPC64)
O << "\t.quad\t0\n";
else
O << "\t.long\t0\n";
}
}
// Emit initial debug information.
DW.EndModule();
// Funny Darwin hack: This flag tells the linker that no global symbols
// contain code that falls through to other global symbols (e.g. the obvious
// implementation of multiple entry points). If this doesn't occur, the
// linker can safely perform dead code stripping. Since LLVM never generates
// code that does this, it is always safe to set.
O << "\t.subsections_via_symbols\n";
return AsmPrinter::doFinalization(M);
}
/// createPPCAsmPrinterPass - 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::createPPCAsmPrinterPass(std::ostream &o,
PPCTargetMachine &tm) {
const PPCSubtarget *Subtarget = &tm.getSubtarget<PPCSubtarget>();
if (Subtarget->isDarwin()) {
return new DarwinAsmPrinter(o, tm, tm.getTargetAsmInfo());
} else {
return new LinuxAsmPrinter(o, tm, tm.getTargetAsmInfo());
}
}