scale.backend.alpha
Class PrologMarker

java.lang.Object
  scale.backend.Instruction
      scale.backend.Marker
          scale.backend.alpha.PrologMarker

All Implemented Interfaces:

java.lang.Cloneable

public class PrologMarker
extends Marker

This class marks the position for the routine prolog.

$Id: PrologMarker.java,v 1.9 2007-10-04 19:57:52 burrill Exp $

Copyright 2007 by the Scale Compiler Group,
Department of Computer Science
University of Massachusetts,
Amherst MA. 01003, USA
All Rights Reserved.

Assembly language for the Alpha requires that the assembly program specify information about a routine for the loader and debugger. This "prolog" information must come after various instructions that comprize the routine entry.

Constructor Summary

PrologMarker(int mask, int fmask, int frameReg, int frameSize, int frameOffset, boolean usesGp)
Create a marker for generating the routine prolog information.

Method Summary

void	assembler(Assembler asm, Emit emit) Insert the assembler directive for the prolog.
boolean	usesGp() Return true if the routine requires a GP register value.

Methods inherited from class scale.backend.Marker

getExecutionCycles, getOpcode, independent, instructionSize, isMarker, nullify, remapDestRegister, remapRegisters, remapSrcRegister, specifyRegisterUsage, toString

Methods inherited from class scale.backend.Instruction

canBeDeleted, clone, copy, defs, ehash, getBBID, getCopyDest, getCopySrc, getDestRegister, getFunctionalUnit, getLoopNumber, getNext, getPredicate, getPredicates, getSrcRegisters, getTag, isBranch, isCopy, isLabel, isLoad, isMandatory, isPhi, isPredicated, isPredicatedOnTrue, isPrefetch, isSpillInstruction, isSpillLoadPoint, isSpillStorePoint, isStore, markSpillInstruction, mods, nullified, numPredicates, removePredicates, setBBID, setLoopNumber, setMandatory, setNext, setPredicate, setPredicate, setPredicatedOnTrue, setPredicates, setsSpecialReg, setTag, specifyNotSpillLoadPoint, specifySpillStorePoint, uses

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

PrologMarker

public PrologMarker(int mask,
                    int fmask,
                    int frameReg,
                    int frameSize,
                    int frameOffset,
                    boolean usesGp)

Create a marker for generating the routine prolog information.

While executing the routine:

• virtual_frame_pointer = stack_pointer + frameSize
• saved register address = virtual_frame_pointer - frameOffset

The stack_pointer is kept in the SP register.

Parameters:

mask - specifies which integer registers are saved by this routine

fmask - specifies which floating point registers are saved by this routine

frameReg - specifies which register is used as the stack pointer

frameSize - specifies the size in bytes of the stack frame for this routine and must be a multiple of 16

frameOffset - specifies the offset from the virtual frame pointer to the saved registers

usesGp - register is true if this routine requires a GP register value

Method Detail

usesGp

public boolean usesGp()

Return true if the routine requires a GP register value.

assembler

public void assembler(Assembler asm,
                      Emit emit)

Insert the assembler directive for the prolog.

Overrides:

assembler in class Marker