Perl 6

SMOP Mold: Revision 29

(Mold is currently under implementation)
SMOP Mold is a register based interpreter implementation
A DSL called m0ld is used to represent mold opcodes in text form

A Mold block(?) is composed of three parts

* the number of registers used by the program (not counting the ones used to put constants or the 3 special ones)
* constants - which are put into registers
* opcodes

The registers 1,2,3 are initialised with

* interpreter
* identifier
* capture

^^ Opcodes

^^^ Call

$target = $invocant.$method_name($pos1,$pos2,:$named1($named1_value)...)

Creates a capture and calls method whose name is stored in $method_name using the responder interface of $invocant

^^^ Call2

$target = $invocant.$method_name(|$catpure)

^^^ Goto

goto label

Jumps to label

^^^ Br

if $condition {goto iftrue} else {goto iffalse}

Jumps to iiftrue if $condition is equal to a native True, to iffalse if it's equal to False, aborts executions and prints out an error otherwise (TODO throw an exception)

^^ Exampe

$*OUT.print("hello world\n") is translated to

.pre
# register declarations
my $r10;
my $r11;
my $r12; # we have to store even unused return values somewhere

# constants
my $r4 = $SMOP__S1P__RootNamespace;
my $r5 = "postcircumfix:{ }";
my $r6 = "$*OUT";
my $r7 = "FETCH";
my $r8 = "print";
my $r9 = "hello world\n";


#opcodes
$r10 = $r4.$r5($r6);
$r11 = $r10.$r7();
$r12 = $r11.$r8($r9);
.pre

The opcodes part ultimatly compiles to such byte code

.pre
# will be filled in tomorrow
.pre