Vtbody Formation

Vtbody Formation encapsulates a specified set of operators into a new vtbody, which is then CALLed from the original vtbody. This is the inverse of Vtbody Inline Expansion. An example of Vtbody Formation is shown in Figure 3-3, where an increment statement and its contents are encapsulated into a separate vtbody. 

Figures. Before and After Vtbody Formation 3.2. SELECT TRANSFORMATIONS...

The next step in forming pipestages is to place the SELECT stages into separate vtbodies, then transform each vtbody into a process and then a pipestage. First, Vtbody Formation is used to encapsulate each SELECT into a separate vtbody. As shown in Figure 8-14, this results in four vtbodies an IFETCH vtbody, which increments the PC a DECODE vtbody, which decodes the instruction and addressing mode an OPFETCH vtbody, which calculates the effective address and fetches the operand and an EXECUTE vtbody, which executes the instruction. 

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