Compiler Desgining

• Test Next Week
• This and Next Week are Advising Weeks or Else!!

DATA STRUCTURES

1. Array ---> Computed Offsets
2. Object
3. Dynamic Structures (Linked List)
4. Union Structure --> Named of sets
5. Record / Struct -->

1. Array: 

.

.

.

ARR[5] = 7; Compute

. ADDR ARR ==> B.A + 100  ==> "x"

2. oBJECT

3. dYNAMIC Structures (Link List)

4. UNION Structure

5. Record / Struct

example:

Record Student Record:

NAME	char[20]    offset is 0
AGE	int    offset is 20
GPA	FLOAT    offset is 24
.	.

StudentRecord s;

s.AGE = 14; // what address should be interpreted for AGE (its called Name Offset)

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     code to 

complete LHS address?    Lets say X = BaseAddress + 200

 (take X and start adding the sizes of other data types )

Quote of the Day:

"Blowing up is better than getting Garbage" 

The Quote is in reference to dangaling reference pointers.

"Don't step up to the plate unless you'v got sholders"

-= xxx END oF Data Structures xxx =-

ERRORS

- Detection Issues

- Recovery Issues  (when illegal character is found show error and discard) 

- Reporting Issues

Compile Time view Run Time View

Data Structures: Arrays (Dynamic)

Dynamic Arrays:

(1) Can be restricted on the fly.
(2) Size can be specified in terms of a variable. Therefore, not known until run-time.

Q. What do we have to hold space for in every Activation Record.
A. Local variables(usr var's), old program counter (where to return back), base pointer, top pointer, temporary variable (automatically created),


Q. What is a dynamic chain in respect to activation record?
A. when you point back to the environment where you have been called.


Q. What is a "Dope Vector"?
A. Any information we need during the runtime, all the information is stored inside the DopeVector.



Q. What kind of other relevant information be stored in Dope Vector?
A.



Q. If compiler writer was care less, it may lead to garbage issues and memory wasn't de-allocated at the rite time.
A. There has to be appropriate code for de-allocation in the compiler or else how would anyone know the generated code is leading to garbage.



Talked about the resumption model in pl1 (known as try{} catch{} block in .net)

Fortran Flat Memory Model:- is contrasted to the stack memory model.

Fortran didn't support recurssion because of the flat memory model. We know how much memory is required at the compile time. and all the functions. All the varriables are static in nature.


Realization: Students listining in the class what leads to the feedbacks from student. How much does the teacher in class motivates student to input + process. A student motivated by the teacher would have developed a way of inputing and processing, be able to follow the thinking process.
input + processing v.s input only (then Process powerfully)

Blinking LED Source CODE for PIC18F4553 with Bootloader

After so much of painful tries of trying to get a Blink LED source code to work for PIC18f4553... I realized, I could work on the bootloader code and have that darn LED blink on the PortAbits.RN1.