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Diffstat (limited to 'contrib/llvm/lib/Target/MBlaze/MBlazeAsmPrinter.cpp')
-rw-r--r-- | contrib/llvm/lib/Target/MBlaze/MBlazeAsmPrinter.cpp | 326 |
1 files changed, 326 insertions, 0 deletions
diff --git a/contrib/llvm/lib/Target/MBlaze/MBlazeAsmPrinter.cpp b/contrib/llvm/lib/Target/MBlaze/MBlazeAsmPrinter.cpp new file mode 100644 index 0000000..e9f340f --- /dev/null +++ b/contrib/llvm/lib/Target/MBlaze/MBlazeAsmPrinter.cpp @@ -0,0 +1,326 @@ +//===-- MBlazeAsmPrinter.cpp - MBlaze 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 GAS-format MBlaze assembly language. +// +//===----------------------------------------------------------------------===// + +#define DEBUG_TYPE "mblaze-asm-printer" + +#include "MBlaze.h" +#include "MBlazeSubtarget.h" +#include "MBlazeInstrInfo.h" +#include "MBlazeTargetMachine.h" +#include "MBlazeMachineFunction.h" +#include "MBlazeMCInstLower.h" +#include "InstPrinter/MBlazeInstPrinter.h" +#include "llvm/Constants.h" +#include "llvm/DerivedTypes.h" +#include "llvm/Module.h" +#include "llvm/CodeGen/AsmPrinter.h" +#include "llvm/CodeGen/MachineFunctionPass.h" +#include "llvm/CodeGen/MachineConstantPool.h" +#include "llvm/CodeGen/MachineFrameInfo.h" +#include "llvm/CodeGen/MachineInstr.h" +#include "llvm/MC/MCInst.h" +#include "llvm/MC/MCStreamer.h" +#include "llvm/MC/MCAsmInfo.h" +#include "llvm/MC/MCSymbol.h" +#include "llvm/Target/Mangler.h" +#include "llvm/Target/TargetData.h" +#include "llvm/Target/TargetLoweringObjectFile.h" +#include "llvm/Target/TargetMachine.h" +#include "llvm/Target/TargetOptions.h" +#include "llvm/Support/ErrorHandling.h" +#include "llvm/Support/TargetRegistry.h" +#include "llvm/Support/raw_ostream.h" +#include <cctype> + +using namespace llvm; + +namespace { + class MBlazeAsmPrinter : public AsmPrinter { + const MBlazeSubtarget *Subtarget; + public: + explicit MBlazeAsmPrinter(TargetMachine &TM, MCStreamer &Streamer) + : AsmPrinter(TM, Streamer) { + Subtarget = &TM.getSubtarget<MBlazeSubtarget>(); + } + + virtual const char *getPassName() const { + return "MBlaze Assembly Printer"; + } + + void printSavedRegsBitmask(); + void emitFrameDirective(); + virtual void EmitFunctionBodyStart(); + virtual void EmitFunctionBodyEnd(); + virtual void EmitFunctionEntryLabel(); + + virtual bool isBlockOnlyReachableByFallthrough(const MachineBasicBlock *MBB) + const; + + bool PrintAsmOperand(const MachineInstr *MI, unsigned OpNo, + unsigned AsmVariant, const char *ExtraCode, + raw_ostream &O); + void printOperand(const MachineInstr *MI, int opNum, raw_ostream &O); + void printUnsignedImm(const MachineInstr *MI, int opNum, raw_ostream &O); + void printFSLImm(const MachineInstr *MI, int opNum, raw_ostream &O); + void printMemOperand(const MachineInstr *MI, int opNum, raw_ostream &O, + const char *Modifier = 0); + + void EmitInstruction(const MachineInstr *MI); + }; +} // end of anonymous namespace + +// #include "MBlazeGenAsmWriter.inc" + +//===----------------------------------------------------------------------===// +// +// MBlaze Asm Directives +// +// -- Frame directive "frame Stackpointer, Stacksize, RARegister" +// Describe the stack frame. +// +// -- Mask directives "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 R19,48,R15 +// .mask 0xc0000000,-8 +// addiu R1, R1, -48 +// sw R15, 40(R1) +// sw R19, 36(R1) +// +// With a 0xc0000000 mask, the assembler knows the register 15 (R15) and +// 19 (R19) are saved at prologue. As the save order on prologue is from +// left to right, R15 is saved first. A -8 offset means that after the +// stack pointer subtration, the first register in the mask (R15) will be +// saved at address 48-8=40. +// +//===----------------------------------------------------------------------===// + +// Print a 32 bit hex number with all numbers. +static void printHex32(unsigned int Value, raw_ostream &O) { + O << "0x"; + for (int i = 7; i >= 0; i--) + O.write_hex((Value & (0xF << (i*4))) >> (i*4)); +} + +// 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 MBlazeAsmPrinter::printSavedRegsBitmask() { + const TargetFrameLowering *TFI = TM.getFrameLowering(); + const TargetRegisterInfo &RI = *TM.getRegisterInfo(); + + // CPU Saved Registers Bitmasks + unsigned int CPUBitmask = 0; + + // Set the CPU Bitmasks + const MachineFrameInfo *MFI = MF->getFrameInfo(); + const std::vector<CalleeSavedInfo> &CSI = MFI->getCalleeSavedInfo(); + for (unsigned i = 0, e = CSI.size(); i != e; ++i) { + unsigned Reg = CSI[i].getReg(); + unsigned RegNum = getMBlazeRegisterNumbering(Reg); + if (MBlaze::GPRRegClass.contains(Reg)) + CPUBitmask |= (1 << RegNum); + } + + // Return Address and Frame registers must also be set in CPUBitmask. + if (TFI->hasFP(*MF)) + CPUBitmask |= (1 << getMBlazeRegisterNumbering(RI.getFrameRegister(*MF))); + + if (MFI->adjustsStack()) + CPUBitmask |= (1 << getMBlazeRegisterNumbering(RI.getRARegister())); + + // Print CPUBitmask + OutStreamer.EmitRawText("\t.mask\t0x" + Twine::utohexstr(CPUBitmask)); +} + +/// Frame Directive +void MBlazeAsmPrinter::emitFrameDirective() { + if (!OutStreamer.hasRawTextSupport()) + return; + + const TargetRegisterInfo &RI = *TM.getRegisterInfo(); + unsigned stkReg = RI.getFrameRegister(*MF); + unsigned retReg = RI.getRARegister(); + unsigned stkSze = MF->getFrameInfo()->getStackSize(); + + OutStreamer.EmitRawText("\t.frame\t" + + Twine(MBlazeInstPrinter::getRegisterName(stkReg)) + + "," + Twine(stkSze) + "," + + Twine(MBlazeInstPrinter::getRegisterName(retReg))); +} + +void MBlazeAsmPrinter::EmitFunctionEntryLabel() { + if (OutStreamer.hasRawTextSupport()) + OutStreamer.EmitRawText("\t.ent\t" + Twine(CurrentFnSym->getName())); + AsmPrinter::EmitFunctionEntryLabel(); +} + +void MBlazeAsmPrinter::EmitFunctionBodyStart() { + if (!OutStreamer.hasRawTextSupport()) + return; + + emitFrameDirective(); + printSavedRegsBitmask(); +} + +void MBlazeAsmPrinter::EmitFunctionBodyEnd() { + if (OutStreamer.hasRawTextSupport()) + OutStreamer.EmitRawText("\t.end\t" + Twine(CurrentFnSym->getName())); +} + +//===----------------------------------------------------------------------===// +void MBlazeAsmPrinter::EmitInstruction(const MachineInstr *MI) { + MBlazeMCInstLower MCInstLowering(OutContext, *this); + + MCInst TmpInst; + MCInstLowering.Lower(MI, TmpInst); + OutStreamer.EmitInstruction(TmpInst); +} + +// Print out an operand for an inline asm expression. +bool MBlazeAsmPrinter:: +PrintAsmOperand(const MachineInstr *MI, unsigned OpNo, + 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. + + switch (ExtraCode[0]) { + default: + // See if this is a generic print operand + return AsmPrinter::PrintAsmOperand(MI, OpNo, AsmVariant, ExtraCode, O); + } + + printOperand(MI, OpNo, O); + return false; +} + +void MBlazeAsmPrinter::printOperand(const MachineInstr *MI, int opNum, + raw_ostream &O) { + const MachineOperand &MO = MI->getOperand(opNum); + + switch (MO.getType()) { + case MachineOperand::MO_Register: + O << MBlazeInstPrinter::getRegisterName(MO.getReg()); + break; + + case MachineOperand::MO_Immediate: + O << (int32_t)MO.getImm(); + break; + + case MachineOperand::MO_FPImmediate: { + const ConstantFP *fp = MO.getFPImm(); + printHex32(fp->getValueAPF().bitcastToAPInt().getZExtValue(), O); + O << ";\t# immediate = " << *fp; + break; + } + + case MachineOperand::MO_MachineBasicBlock: + O << *MO.getMBB()->getSymbol(); + return; + + case MachineOperand::MO_GlobalAddress: + O << *Mang->getSymbol(MO.getGlobal()); + break; + + case MachineOperand::MO_ExternalSymbol: + O << *GetExternalSymbolSymbol(MO.getSymbolName()); + break; + + case MachineOperand::MO_JumpTableIndex: + O << MAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber() + << '_' << MO.getIndex(); + break; + + case MachineOperand::MO_ConstantPoolIndex: + O << MAI->getPrivateGlobalPrefix() << "CPI" + << getFunctionNumber() << "_" << MO.getIndex(); + if (MO.getOffset()) + O << "+" << MO.getOffset(); + break; + + default: + llvm_unreachable("<unknown operand type>"); + } +} + +void MBlazeAsmPrinter::printUnsignedImm(const MachineInstr *MI, int opNum, + raw_ostream &O) { + const MachineOperand &MO = MI->getOperand(opNum); + if (MO.isImm()) + O << (uint32_t)MO.getImm(); + else + printOperand(MI, opNum, O); +} + +void MBlazeAsmPrinter::printFSLImm(const MachineInstr *MI, int opNum, + raw_ostream &O) { + const MachineOperand &MO = MI->getOperand(opNum); + if (MO.isImm()) + O << "rfsl" << (unsigned int)MO.getImm(); + else + printOperand(MI, opNum, O); +} + +void MBlazeAsmPrinter:: +printMemOperand(const MachineInstr *MI, int opNum, raw_ostream &O, + const char *Modifier) { + printOperand(MI, opNum, O); + O << ", "; + printOperand(MI, opNum+1, O); +} + +/// 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 MBlazeAsmPrinter:: +isBlockOnlyReachableByFallthrough(const MachineBasicBlock *MBB) const { + // 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. + const MachineBasicBlock *Pred = *PI; + + if (!Pred->isLayoutSuccessor(MBB)) + return false; + + // If the block is completely empty, then it definitely does fall through. + if (Pred->empty()) + return true; + + // Check if the last terminator is an unconditional branch. + MachineBasicBlock::const_iterator I = Pred->end(); + while (I != Pred->begin() && !(--I)->isTerminator()) + ; // Noop + return I == Pred->end() || !I->isBarrier(); +} + +// Force static initialization. +extern "C" void LLVMInitializeMBlazeAsmPrinter() { + RegisterAsmPrinter<MBlazeAsmPrinter> X(TheMBlazeTarget); +} |