Compiler Construction Solved MCQs

Three address code involves Exactly 3 address At most most 3 address No unary operators None of these       _____________________________________________________________________________________

An intermediate code form is Postfix notation Syntax trees Three address code All of these       _____________________________________________________________________________________

In operator precedence parsing , precedence relations are defoned For all pair of non terminals For all pair of terminals To delimit the handle Only for a certain pair of terminals       _____________________________________________________________________________________

Relocating bits used by relocating loader are specified by Relocating loader itself Linker Assembler Macro processor       _____________________________________________________________________________________

A compiler for a high level language that runs on one machine and produce code for different machine is called Optimizing compiler One pass compiler Cross compiler Multipass compiler       _____________________________________________________________________________________

Synthesized attribute can be easily simulated by a LL grammar Ambiguous grammar LR grammar None of the above       _____________________________________________________________________________________

The output of a lexical analyzer is Machine code Intermediate code A stream of tokens A parse tree       _____________________________________________________________________________________

Running time of a program depends on The way the registers and addressing modes are used The order in which computations are performed The usage of machine idioms All of these       _____________________________________________________________________________________

Reduction in strength means Replacing run time computation by compile time computation Removing loop invariant computation Removing common sub expression Replacing a costly operation by a relatively cheaper one       _____________________________________________________________________________________

_________or scanning is the process where the stream of characters making up the source program is read from left to right and grouped into tokens. Lexical analysis Diversion Modeling None of the above       _____________________________________________________________________________________

Task of the lexical analysis To parse the source program into the basic elements or tokens of the language To build a literal table and an identifier table To build a uniform symbol table All of these       _____________________________________________________________________________________

Shift reduce parsers are Top down parser Bottom up parser May be top down or bottom up parser None of the above       _____________________________________________________________________________________

Any description error can be repaired by Insertion alone Deletion alone Insertion and deletion alone Replacement alone       _____________________________________________________________________________________

The linker is similar to interpreter uses source code as its input is required to create a load module none of the above       _____________________________________________________________________________________

A grammar that produces more than one parse tree for some sentence is called Ambiguous Unambiguous Regular None of these       _____________________________________________________________________________________

In an absolute loading scheme which loader function is accomplished by assembler ? re-allocation allocation linking loading       _____________________________________________________________________________________

Intermediate code generation phase gets input from Lexical analyzer Syntax analyzer Semantic analyzer Error handling       _____________________________________________________________________________________

We can optimize code by Dead code elimination Common subprograms Copy intermediate loop Loop declaration       _____________________________________________________________________________________

Code can be optimized at Source from user Target code Intermediate code All of the above       _____________________________________________________________________________________

Whether a given pattern constitutes a token or not depends on the Source language Target language Compiler All of these       _____________________________________________________________________________________

YACC builds up SLR parsing table Canonical LR parsing table LALR parsing table None of the above       _____________________________________________________________________________________

Type checking is normally done during Lexical analysis Syntax analysis Syntax directed translation Code optimization       _____________________________________________________________________________________

A top down parser generates Right most derivation Right most derivation in reverse Left most derivation Left most derivation in reverse       _____________________________________________________________________________________

Which of the following does not interrupt a running process? A device Timer Scheduler Power failure       _____________________________________________________________________________________

In an absolute loading scheme, which loader function is accomplished by a loader ? Re-allocation Allocation Linking Loading       _____________________________________________________________________________________

The lexical analyzer takes_________as input and produces a stream of_______as output. Source program,tokens Token,source program Either A and B None of the above       _____________________________________________________________________________________

Which of the following can be accessed by transfer vector approach of linking? External data segments External subroutines Data located in other procedure All of these       _____________________________________________________________________________________

___________is a graph representation of a derivation. The parse tree The oct tree The binary tree None of the above       _____________________________________________________________________________________

The optimization which avoids test at every iteration is Loop unrolling Loop jamming Constant folding None of these       _____________________________________________________________________________________

Syntax directed translation scheme is desirable because It is based on the syntax Its description is independent of any implementation It is easy to modify All of these       _____________________________________________________________________________________

A parser with the valid prefix property is advantageous because it Detects error as soon as possible Detects errors as and when they occur Limits the amount of erroneous output passed to the text phase All of these       _____________________________________________________________________________________

Which of the following parser is most powerful? Operator precedence Canonical LR LALR SLR       _____________________________________________________________________________________

Inherited attribute is a natural choice in Keeping track of variable declaration Checking for the correct use of L values and R values Both A and B None of these       _____________________________________________________________________________________

Macro-processors are ______ Hardware Compiler Registers None of the above       _____________________________________________________________________________________

In which way(s) a macroprocessor for assembly language can be implemented ? Independent two-pass processor Independent one-pass processor Expand macrocalls and substitute arguments All of the above       _____________________________________________________________________________________

‘Macro’ in an assembly level program is _______. sub program a complete program a hardware portion relative coding       _____________________________________________________________________________________

The optimization technique which is typically applied on loops is Removal of invariant computation Peephole optimization Constant folding All of these       _____________________________________________________________________________________

Concept which can be used to identify loops is Dominators Reducible graphs Depth first ordering All of these       _____________________________________________________________________________________

Local and loop optimization in turn provide motivation for Data flow analysis Constant folding Pee hole optimization DFA and constant folding       _____________________________________________________________________________________

LR stands for Left to right Left to right reduction Right to left Left to right and right most derivation in reverse       _____________________________________________________________________________________

Grammar of the programming is checked at ________ phase of compiler. semantic analysis code generation syntax analysis code optimization       _____________________________________________________________________________________

Which of the following is not an intermediate code form? Postfix notation Syntax trees Three address codes Quadruples       _____________________________________________________________________________________

A compiler that runs on one machine and produces code for a different machine is called Cross compilation One pass compilation Two pass compilation None of the above       _____________________________________________________________________________________

The graph that shows basic blocks and their successor relationship is called DAG Flow chart Control graph Hamiltonian graph       _____________________________________________________________________________________

A grammar is meaningless If terminal set and non terminal set are not disjoint If left hand side of a production is a single terminal If left hand side of a production has no non terminal All of these       _____________________________________________________________________________________

Which of the following is used for grouping of characters into tokens? Parser Code optimization Code generator Lexical analyzer       _____________________________________________________________________________________

An optimizer compiler Is optimized to occupy less space Is optimized to take less time for execution Optimizes the code None of these       _____________________________________________________________________________________

Pee hole optimization Loop optimization Local optimization Constant folding Data flow analysis       _____________________________________________________________________________________

The action of parsing the source program into proper syntactic classes is called Syntax analysis Lexical analysis Interpretation analysis General syntax analysis       _____________________________________________________________________________________