llvm-6502/lib/Target/PIC16/PIC16AsmPrinter.cpp
Sanjiv Gupta 0608b49819 Detect calls to compiler intrinsics and emit an extern declarations
only for those. These extern declarations to intrinsics are currently 
being emitted at the bottom of generated .s file, which works fine with
gpasm(not sure about MPSAM though).
PIC16 linker generates errors for few cases (function-args/struct_args_5) if you do not include any
extern declarations (even if no intrinsics are being used), but that
needs to be fixed in the linker itself.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@71423 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-11 06:01:38 +00:00

399 lines
13 KiB
C++

//===-- PIC16AsmPrinter.cpp - PIC16 LLVM assembly writer ------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains a printer that converts from our internal representation
// of machine-dependent LLVM code to PIC16 assembly language.
//
//===----------------------------------------------------------------------===//
#include "PIC16AsmPrinter.h"
#include "PIC16TargetAsmInfo.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Function.h"
#include "llvm/Module.h"
#include "llvm/CodeGen/DwarfWriter.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Support/Mangler.h"
#include "llvm/CodeGen/DwarfWriter.h"
#include "llvm/CodeGen/MachineModuleInfo.h"
using namespace llvm;
#include "PIC16GenAsmWriter.inc"
bool PIC16AsmPrinter::printMachineInstruction(const MachineInstr *MI) {
printInstruction(MI);
return true;
}
/// runOnMachineFunction - This uses the printInstruction()
/// method to print assembly for each instruction.
///
bool PIC16AsmPrinter::runOnMachineFunction(MachineFunction &MF) {
this->MF = &MF;
// This calls the base class function required to be called at beginning
// of runOnMachineFunction.
SetupMachineFunction(MF);
// Get the mangled name.
const Function *F = MF.getFunction();
CurrentFnName = Mang->getValueName(F);
// Emit the function variables.
emitFunctionData(MF);
const char *codeSection = PAN::getCodeSectionName(CurrentFnName).c_str();
const Section *fCodeSection = TAI->getNamedSection(codeSection,
SectionFlags::Code);
O << "\n";
// Start the Code Section.
SwitchToSection (fCodeSection);
// Emit the frame address of the function at the beginning of code.
O << "\tretlw low(" << PAN::getFrameLabel(CurrentFnName) << ")\n";
O << "\tretlw high(" << PAN::getFrameLabel(CurrentFnName) << ")\n";
// Emit function start label.
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.
if (I != MF.begin()) {
printBasicBlockLabel(I, true);
O << '\n';
}
// For emitting line directives, we need to keep track of the current
// source line. When it changes then only emit the line directive.
unsigned CurLine = 0;
for (MachineBasicBlock::const_iterator II = I->begin(), E = I->end();
II != E; ++II) {
// Emit the line directive if source line changed.
const DebugLoc DL = II->getDebugLoc();
if (!DL.isUnknown()) {
unsigned line = MF.getDebugLocTuple(DL).Line;
if (line != CurLine) {
O << "\t.line " << line << "\n";
CurLine = line;
}
}
// Print the assembly for the instruction.
printMachineInstruction(II);
}
}
return false; // we didn't modify anything.
}
/// createPIC16CodePrinterPass - Returns a pass that prints the PIC16
/// assembly code for a MachineFunction to the given output stream,
/// using the given target machine description. This should work
/// regardless of whether the function is in SSA form.
///
FunctionPass *llvm::createPIC16CodePrinterPass(raw_ostream &o,
PIC16TargetMachine &tm,
CodeGenOpt::Level OptLevel,
bool verbose) {
return new PIC16AsmPrinter(o, tm, tm.getTargetAsmInfo(), OptLevel, verbose);
}
// printOperand - print operand of insn.
void PIC16AsmPrinter::printOperand(const MachineInstr *MI, int opNum) {
const MachineOperand &MO = MI->getOperand(opNum);
switch (MO.getType()) {
case MachineOperand::MO_Register:
if (TargetRegisterInfo::isPhysicalRegister(MO.getReg()))
O << TM.getRegisterInfo()->get(MO.getReg()).AsmName;
else
assert(0 && "not implemented");
return;
case MachineOperand::MO_Immediate:
O << (int)MO.getImm();
return;
case MachineOperand::MO_GlobalAddress: {
O << Mang->getValueName(MO.getGlobal());
break;
}
case MachineOperand::MO_ExternalSymbol: {
const char *Sname = MO.getSymbolName();
// If its a libcall name, record it to decls section.
if (PAN::getSymbolTag(Sname) == PAN::LIBCALL) {
Decls.push_back(Sname);
}
O << Sname;
break;
}
case MachineOperand::MO_MachineBasicBlock:
printBasicBlockLabel(MO.getMBB());
return;
default:
assert(0 && " Operand type not supported.");
}
}
void PIC16AsmPrinter::printCCOperand(const MachineInstr *MI, int opNum) {
int CC = (int)MI->getOperand(opNum).getImm();
O << PIC16CondCodeToString((PIC16CC::CondCodes)CC);
}
void PIC16AsmPrinter::printDecls(void) {
// If no libcalls used, return.
if (Decls.empty()) return;
const Section *S = TAI->getNamedSection(PAN::getDeclSectionName().c_str());
SwitchToSection(S);
// Remove duplicate entries.
Decls.sort();
Decls.unique();
for (std::list<const char*>::const_iterator I = Decls.begin();
I != Decls.end(); I++) {
O << TAI->getExternDirective() << *I << "\n";
// FIXME: Use PAN::getXXXLabel() funtions hrer.
O << TAI->getExternDirective() << *I << ".args." << "\n";
O << TAI->getExternDirective() << *I << ".ret." << "\n";
}
}
bool PIC16AsmPrinter::doInitialization (Module &M) {
bool Result = AsmPrinter::doInitialization(M);
// FIXME:: This is temporary solution to generate the include file.
// The processor should be passed to llc as in input and the header file
// should be generated accordingly.
O << "\t#include P16F1937.INC\n";
MachineModuleInfo *MMI = getAnalysisIfAvailable<MachineModuleInfo>();
assert(MMI);
DwarfWriter *DW = getAnalysisIfAvailable<DwarfWriter>();
assert(DW && "Dwarf Writer is not available");
DW->BeginModule(&M, MMI, O, this, TAI);
EmitExternsAndGlobals (M);
EmitGlobalData(M);
EmitRomData(M);
return Result;
}
void PIC16AsmPrinter::EmitExternsAndGlobals (Module &M) {
// Emit declarations for external functions.
O << "section.0" <<"\n";
for (Module::iterator I = M.begin(), E = M.end(); I != E; I++) {
std::string Name = Mang->getValueName(I);
if (Name.compare("@abort") == 0)
continue;
// If it is llvm intrinsic call then don't emit
if (Name.find("llvm.") != std::string::npos)
continue;
if (! (I->isDeclaration() || I->hasExternalLinkage()))
continue;
const char *directive = I->isDeclaration() ? TAI->getExternDirective() :
TAI->getGlobalDirective();
O << directive << Name << "\n";
O << directive << PAN::getRetvalLabel(Name) << "\n";
O << directive << PAN::getArgsLabel(Name) << "\n";
}
// Emit header file to include declaration of library functions
// FIXME: find out libcall names.
// O << "\t#include C16IntrinsicCalls.INC\n";
// Emit declarations for external variable declarations and definitions.
for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
I != E; I++) {
// Any variables reaching here with ".auto." in its name is a local scope
// variable and should not be printed in global data section.
std::string Name = Mang->getValueName(I);
if (PAN::isLocalName(Name))
continue;
if (!(I->isDeclaration() || I->hasExternalLinkage() ||
I->hasCommonLinkage()))
continue;
const char *directive = I->isDeclaration() ? TAI->getExternDirective() :
TAI->getGlobalDirective();
O << directive << Name << "\n";
}
}
void PIC16AsmPrinter::EmitRomData (Module &M)
{
SwitchToSection(TAI->getReadOnlySection());
for (Module::global_iterator I = M.global_begin(), E = M.global_end();
I != E; ++I) {
if (!I->hasInitializer()) // External global require no code.
continue;
Constant *C = I->getInitializer();
const PointerType *PtrTy = I->getType();
int AddrSpace = PtrTy->getAddressSpace();
if ((!C->isNullValue()) && (AddrSpace == PIC16ISD::ROM_SPACE)) {
if (EmitSpecialLLVMGlobal(I))
continue;
// Any variables reaching here with "." in its name is a local scope
// variable and should not be printed in global data section.
std::string name = Mang->getValueName(I);
if (PAN::isLocalName(name))
continue;
I->setSection(TAI->getReadOnlySection()->getName());
O << name;
EmitGlobalConstant(C, AddrSpace);
O << "\n";
}
}
}
bool PIC16AsmPrinter::doFinalization(Module &M) {
printDecls();
O << "\t" << "END\n";
bool Result = AsmPrinter::doFinalization(M);
return Result;
}
void PIC16AsmPrinter::emitFunctionData(MachineFunction &MF) {
const Function *F = MF.getFunction();
std::string FuncName = Mang->getValueName(F);
Module *M = const_cast<Module *>(F->getParent());
const TargetData *TD = TM.getTargetData();
unsigned FrameSize = 0;
// Emit the data section name.
O << "\n";
const char *SectionName = PAN::getFrameSectionName(CurrentFnName).c_str();
const Section *fPDataSection = TAI->getNamedSection(SectionName,
SectionFlags::Writeable);
SwitchToSection(fPDataSection);
// Emit function frame label
O << PAN::getFrameLabel(CurrentFnName) << ":\n";
const Type *RetType = F->getReturnType();
unsigned RetSize = 0;
if (RetType->getTypeID() != Type::VoidTyID)
RetSize = TD->getTypeAllocSize(RetType);
//Emit function return value space
// FIXME: Do not emit RetvalLable when retsize is zero. To do this
// we will need to avoid printing a global directive for Retval label
// in emitExternandGloblas.
if(RetSize > 0)
O << PAN::getRetvalLabel(CurrentFnName) << " RES " << RetSize << "\n";
else
O << PAN::getRetvalLabel(CurrentFnName) << ": \n";
// Emit variable to hold the space for function arguments
unsigned ArgSize = 0;
for (Function::const_arg_iterator argi = F->arg_begin(),
arge = F->arg_end(); argi != arge ; ++argi) {
const Type *Ty = argi->getType();
ArgSize += TD->getTypeAllocSize(Ty);
}
O << PAN::getArgsLabel(CurrentFnName) << " RES " << ArgSize << "\n";
// Emit temporary space
int TempSize = PTLI->GetTmpSize();
if (TempSize > 0 )
O << PAN::getTempdataLabel(CurrentFnName) << " RES " << TempSize <<"\n";
// Emit the section name for local variables.
O << "\n";
const char* SecNameLocals = PAN::getAutosSectionName(CurrentFnName).c_str() ;
const Section *fADataSection = TAI->getNamedSection(SecNameLocals,
SectionFlags::Writeable);
SwitchToSection(fADataSection);
// Emit the function variables.
// In PIC16 all the function arguments and local variables are global.
// Therefore to get the variable belonging to this function entire
// global list will be traversed and variables belonging to this function
// will be emitted in the current data section.
for (Module::global_iterator I = M->global_begin(), E = M->global_end();
I != E; ++I) {
std::string VarName = Mang->getValueName(I);
// The variables of a function are of form FuncName.* . If this variable
// does not belong to this function then continue.
// Static local varilabes of a function does not have .auto. in their
// name. They are not printed as part of function data but module
// level global data.
if (! PAN::isLocalToFunc(FuncName, VarName))
continue;
I->setSection(TAI->SectionForGlobal(I)->getName());
Constant *C = I->getInitializer();
const Type *Ty = C->getType();
unsigned Size = TD->getTypeAllocSize(Ty);
FrameSize += Size;
// Emit memory reserve directive.
O << VarName << " RES " << Size << "\n";
}
}
void PIC16AsmPrinter::EmitGlobalData (Module &M)
{
// Set the section names for all globals.
for (Module::global_iterator I = M.global_begin(), E = M.global_end();
I != E; ++I) {
I->setSection(TAI->SectionForGlobal(I)->getName());
}
const PIC16TargetAsmInfo *PTAI = static_cast<const PIC16TargetAsmInfo *>(TAI);
const TargetData *TD = TM.getTargetData();
// Now print all IDATA sections.
std::vector <PIC16Section *>IDATASections = PTAI->IDATASections;
for (unsigned i = 0; i < IDATASections.size(); i++) {
SwitchToSection(IDATASections[i]->S_);
std::vector<const GlobalVariable*> Items = IDATASections[i]->Items;
for (unsigned j = 0; j < Items.size(); j++) {
std::string Name = Mang->getValueName(Items[j]);
Constant *C = Items[j]->getInitializer();
int AddrSpace = Items[j]->getType()->getAddressSpace();
O << Name;
EmitGlobalConstant(C, AddrSpace);
}
}
// Now print all BSS sections.
std::vector <PIC16Section *>BSSSections = PTAI->BSSSections;
for (unsigned i = 0; i < BSSSections.size(); i++) {
SwitchToSection(BSSSections[i]->S_);
std::vector<const GlobalVariable*> Items = BSSSections[i]->Items;
for (unsigned j = 0; j < Items.size(); j++) {
std::string Name = Mang->getValueName(Items[j]);
Constant *C = Items[j]->getInitializer();
const Type *Ty = C->getType();
unsigned Size = TD->getTypeAllocSize(Ty);
O << Name << " " <<"RES"<< " " << Size ;
O << "\n";
}
}
}