Overall Structure

8/3/2019 Overall Structure

1/25

Chuen-Liang Chen, NTU CS&IE / 1Overall Structure

Overall Structure

Chuen-Liang Chen

Department of Computer Science

and Information Engineering

National Taiwan University

[email protected]


2/25


OutlineLanguage Processors

Phases of a Compiler

Compiler Structure

Compiler Construction

Compiler Installation/Porting
http://opt/scribd/conversion/tmp/scratch6058/slide3.xmlhttp://opt/scribd/conversion/tmp/scratch6058/slide6.xmlhttp://opt/scribd/conversion/tmp/scratch6058/slide9.xmlhttp://opt/scribd/conversion/tmp/scratch6058/slide13.xmlhttp://opt/scribd/conversion/tmp/scratch6058/slide20.xmlhttp://opt/scribd/conversion/tmp/scratch6058/slide20.xmlhttp://opt/scribd/conversion/tmp/scratch6058/slide13.xmlhttp://opt/scribd/conversion/tmp/scratch6058/slide9.xmlhttp://opt/scribd/conversion/tmp/scratch6058/slide6.xmlhttp://opt/scribd/conversion/tmp/scratch6058/slide3.xml


3/25


Compiler

sourceprogram

targetprogram

input

output

Interprete

r

sourceprogram outpu

tinput

Language Processors

targetprogram

Just In TimeCompiler

for hotspot

Compiler

sourceprogram

intermediate program outputinput

Virtual Machine(incl.

interpreter)


4/25Chuen-Liang Chen, NTU CS&IE / 4Overall Structure

Tool Chaintoolchain: a set of linked development tools

text editor preprocessor compiler assembler linker/loader debugger, libraries

GNU toolchainGNU makeGCC

GNUbinutils(binary utilities)GNU debugger(gdb)libraries

output of a compiler, may:

assemblyrelocatableabsolute binaryother source
http://www.gnu.org/software/make/http://gcc.gnu.org/http://www.gnu.org/software/binutils/http://www.gnu.org/software/binutils/http://www.gnu.org/software/gdb/http://www.gnu.org/software/gdb/http://www.gnu.org/software/binutils/http://www.gnu.org/software/binutils/http://gcc.gnu.org/http://www.gnu.org/software/make/



GNU Maketo automate the process of converting files

rule format

target: prerequisites(tab) command 1command n

target: file to be created, or action nameprerequisites: input files to create the target

commands: make process if any of the prerequisites changesimple example

helloWorld: helloWorld.occ -o helloWorld helloWorld.o

helloWorld.o: helloWorld.c

cc -c helloWorld.cclean:

rm helloWorld helloWorld.ousage: make or make clean



Phases of a Compiler



Analyseslexical

regular expression

syntactic (structure)

context-free grammar

semantics (meaning)

static semantics attribute grammar

run-time semantics

Vienna definition

language, ...

syntax error a = b + ;

static semantic error int a , b ;

boolean c ;

a = b + c ;

run-time semantic error int a , b , c ;

scanf(%d, &b);

// assume: max int

c = 1 ; a = b + c ;



Phases of a Compiler Example



Compiler Structuresyntax-directed translation

driven by the syntactic structure of source program

call graph (multi-passes)

machinecode

token

SS: syntactic structure (abstract syntax tree)IR: intermediate representations

sourcecode

SS

IR

main

parser

scanner semanticroutines

codegenerator

symbol tableattribute table

opt 2opt 1


10/25Chuen-Liang Chen, NTU CS&IE /Overall Structure

Intermediate Representation of a Compiler

front-endfrom source code to intermediate codeanalysis phaseslanguage dependent

intermediate representation (intermediate code)

back-endfrom intermediate code to target code

synthesis phasesmachine dependent

intermediaterepresentatio

n

C front-end

Fortran front-end

Java front-end

arm back-end

i386 back-end

mips back-end

sparc back-end


11/25

Chuen-Liang Chen, NTU CS&IE /Overall Structure

GCC Historyhistory / releases

1987 Gnu C Compiler1997~1999 Experimental Gnu Compiler System (EGCS)

pronounced eggs

EGCS & GCC reunited in 1999; winner: EGCS

1999 GCC Development Mission Statement1999 Gnu Compiler Collection 2.95

2001 GCC 3.02005/04 GCC 4.0.0 2009/04 GCC 4.4.02006/02 GCC 4.1.0 2010/04 GCC 4.5.02007/05 GCC 4.2.0 2011/03 GCC 4.6.02008/03 GCC 4.3.0 2011/10 GCC 4.6.2

design and development goals (from Mission Statement)new languages (front-end, language-dependent)new optimizations (middle-end)new targets (back-end, machine-dependent)improved runtime librariesfaster debug cyclevarious other infrastructure improvements
http://gcc.gnu.org/wiki/Historyhttp://gcc.gnu.org/releases.htmlhttp://gcc.gnu.org/gccmission.htmlhttp://gcc.gnu.org/gccmission.htmlhttp://gcc.gnu.org/releases.htmlhttp://gcc.gnu.org/wiki/History


12/25


GCC Structure

source

rtl / cfg

assembly

tree/ cfg

parsinggimplification

build_cfg

expand

final

tree optimizations

rtl optimizations

machineindependent

machinedependent


13/25


Compiler Constructionhand-written

compiler generatoraka, compiler compiler

how to use C to write a C compiler?


14/25


Pascal P-code (1/5)

(format, input output)Machine code, Assembly, P-code, Pascal, Data

without high level language support

P-code

Interpreter(A, Pc ) 6553940663

0653636594

Sorting

(A, DD)

Assembler(M, AM)

P-code interpreter(M, Pc )

Sorting(M, DD)

Platform (Hardware + OS)


15/25


Interpretersoftware CPU

int IR; // IR: instruction register

int PC = 0; // PC: program counter int code[ ];while(1) { // clockIR = code[PC]; // instruction fetchingswitch (IR) { // instruction decodingcase 1: execution of opcode 1; break;case 2: execution of opcode 2; break;

case n: execution of opcode n; break;// instruction execution// data fetching (using PC)}PC += instruction_length; // update program counter}

easier than a compiler


16/25


Pascal P-code (2/5)


slower compilation, slower execution

PascalCompiler

(Pc,PaPc)

P-code

Interpreter(A, Pc )

Pascal

Compiler(Pa,PaPc) 6553940663

06536365

94

Sorting

(Pa,DD)

Sorting(Pc,DD)

Assembler(M, AM)




17/25


Pascal P-code (3/5)


slower compilation, faster execution

P-code

Interpreter(A, Pc )

Pascal

Compiler(Pa,PaPc)

Pascal

Compiler(Pa,PaM) 6553940663

0653636594

Sorting

(Pa,DD)

PascalCompiler

(Pc,PaPc)

PascalCompiler(Pc,PaM)

Assembler(M, AM)


Sorting(M, DD)



18/25


Pascal P-code (4/5)


faster compilation, faster execution

P-code

Interpreter(A, Pc )

PascalCompiler

(Pc,PaPc)

Pascal

Compiler(Pa,PaPc)

Pascal

Compiler(Pa,PaM)

PascalCompiler(Pc,PaM)

6553940663

0653636594

Sorting

(Pa,DD)

Assembler(M, AM)


PascalCompiler(M, PaM)

Sorting(M, DD)



19/25


Pascal P-code (5/5)

P-code

Interpreter(A, Pc )

Pascal

Compiler(Pa,PaPc)

Pascal

Compiler(Pa,PaA)

PascalCompiler(A, PaA)

PascalCompiler

(Pc,PaPc)

PascalCompiler(Pc,PaA)

Assembler(M, AM)


Assembler(M, AM)

PascalCompiler(M, PaA)


l (format, inputoutput)

u Machine code, Assembly, P-code, Pascal, Datal easier implementation


20/25


Compiler Installation/Portingbuild a GCC on a Sparc workstation

(build machine)

run the GCC for a sorting program on an i386 PC

(host machine)execute the sorting on an Arm embedded system

(target machine)

classification of compilers

build host target classification application example

A A A native compiler upgradeA A C cross developing env. for

embedded system

A B A cross-back

A B B crossed native new CPU, powerful

enough to run compilerA B C canadian


21/25


Build, Host & Target Machines

compilerexecutable(B, src H)

compilersource

compilerexecutable(H, src T)

applicationsource

applicationexecutable(T, ? ?)

Build Machine Host MachineTarget

Machine


22/25


Comparison of Different Versions

gcc 2.95(Csparc)

[anyexe]

gcc 4.6.2(Csparc)

[anyexe]

sorting[src]

sorting[sparc exe]

{2.95 tech}

sorting[sparc exe]

{4.6.2 tech}

gcc 4.6.2(Csparc)[sparc exe]{2.95 tech}

gcc 4.6.2(Csparc)[sparc exe]{4.6.2 tech}

searching[src]

searching[sparc exe]{4.6.2 tech}

searching[sparc exe]{4.6.2 tech}

l worse execution

l better execution

l worse compilationl same execution

l better compilationl same execution

(s/w function)[code format]{code quality}


23/25


Native GCC Building

assume: each GCC stagebundles the existed binutils

(as, ld)stage new functionworse code quality

stage new functionbetter code quality

stage same as stage converged

gcc 2.95(Csparc)

[sparc exe]

gcc 4.6.2(Csparc)[sparc exe]

{2.95 tech}



gcc 4.6.2sparc.md

[src]

library[src]

library

[sparc obj]{4.6.2 tech}

build

host

target

helloWorld[sparc exe]{4.6.2 tech}

helloWorld[src]

-c -c


24/25


Cross GCC Buildingassume: build machine (sparc) already has the newest

native gcc & binutils

cross binutils is required !!!

gccarm.md

[src]

binutilscpu-arm.c

[src]

library[src]

library[arm obj]

helloWorld[arm exe]

helloWorld[src]

-c -c

-Slibrary

[arm asm]

-S

gcc(Carm)[sparc exe]

binutils(arm)

[sparc exe]

gcc(Csparc)[sparc exe]

binutils(sparc)

[sparc exe]

C il d C S i


25/25


Compiler and Computer Sciencecompiler and programming language

new language features new compilation challengeexisted compiling problem modified language features

compiler and architecture/platformnew resources new compilation challenge

optimization technology other fields in computer science

Documents

Overall Structure