Version 6 (modified by cotto, 5 years ago)

fill in some more descriptions, remove Lorito name field

The VM for the Smalltalk interpreter Squeak has a design similar to our eventual goal for Parrot, namely that it has a small core of operations implemented in C with the rest of the language being implemented in terms of these operations. In hope of jumpstarting the design and implementation of Lorito (aka L1), this page lists the 42 operations used by Squeak's VM. The hope is that a similar set of operations can be used as Lorito ops.

Because most Parrot developers are not familiar with Smalltalk, so the following table lists the operations used to implement Squeak (available  here), example Smalltalk code, a description, their equivalent in C syntax and an appropriate name for the Lorito op. Many definitions were stolen from  here.

Memory access goes through a set of 6 macros for reading and writing single bytes, 4-byte words and 8-byte floats.

Squeak operation example Smalltalk codedescriptionequivalent C code
& logical and (no short-circuiting)
| logical or (no short-circuiting)
and: logical and (short-circuiting)
or: logical or (short-circuiting)
not logical not
+ 5+5 addition a = 5 + 5
- 4-3 subtractiona = 4 - 3
* 6*7 multiplicationa = 6 * 7
// 15//5 division a = 15 / 5
\\ 7\\3 mod a = 7 % 3
max: |a b| a := 1. b := 2. a max: b.maxa = a>b?a:b;
min: |a b| a := 1. b := 2. a min: b.mina = a<b?a:b;
bitAnd: bitwise and
bitOr: bitwise or
bitXor: bitwise xor
bitShift: bitwise shift
< 5<3 less than a = 5 < 3
<= 5<=3 less than or equala = 5 <= 3
= 5=3 equality (deep)a = 5 == 3
> 5>3 greater thana = 5 > 3
>= 5>=3 greater than or equala = 5 <= 3
~= 5=~3 inequality (deep)
== 5==5 equality (shallow)a = 5 == 5
isNil null test
notNil non-null test
whileTrue: while loop
whileFalse: while loop
to:do:
to:by:do:
ifTrue: if
ifFalse: unless
ifTrue:ifFalse: if/else
ifFalse:ifTrue:
at: hash/array read
at:put: hash/array write
<<
>>
bitInvert32 bitwise negation
preIncrement
integerValueOf:
integerObjectOf:
isIntegerObject: