The TASM Language Reference Manual Version 1.1 - Synrc

The distribution of the ⊕ operator over the set of consumed resources is the same
as for the ⊗ operator:
RC p ⊕ RC c = (rc p1 , . . . , rc pn ) ⊕ (rc c1 , . . . , rc cn )
= (rc p1 ⊕ rc c1 , . . . , rc pn ⊕ rc cn )
= ((rr p1 , rac p1 ) ⊕ (rr c1 , rac c1 ), . . . ,
(rr pn , rac pn ) ⊕ (rr cn , rac cn ))
= ((rr p1 , rac p1 ⊕ rac c1 ), ...
((rr pn , rac pn ⊕ rac cn ))
The resources consumed by the rule execution will be determined by the parent,
if a resource annotation exists in the parent. Otherwise, it will be determined by the
child:
rac p ⊕ rac c =
{
rac c
rac p
if rac p = ⊥
otherwise
Intuitively, the composition between parent update sets and child update sets is
such that the parent machine overrides the child machine. If the parent machine has
annotations, those annotations override the annotations from child machines. If a parent
machine doesn’t have an annotation, then its behavior is defined by the annotations of
the auxiliary machines it uses.
Figure 2.1 shows a hierarchy of machines for an sample rule execution. Each numbered
square represents a machine. Machine ”1” represents the rule of the main machine
being executed; all other squares represent either sub machines or function machines
used to derive the update set returned by the main machine. Machine ”3” is
an example of a machine that plays the role of parent (of machine ”7”) and child (of
machine ”1”).
1
2 3 4
5 6
7
Figure 2.1: Hierarchical composition
Each machine generates an update set T RU i , where i is the machine number. The
derivation of the returned update set is done in a bottom-up fashion, where T RU ret is
the update set returned by the main machine:
20