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name1:   JUMP-IF-NIL reg1, name1a 
         RETURN                   ;return the value in reg2 
name1a:  GOTO name2

name2:   <code for b>             ;result in reg1 
         LOAD regZ,[name4]        ;[name4] is the closure for name4 
         GOTO name3 

name3:  JUMP-IF-NIL reg1,name3a 
        RETURN                    ;return the value in reg1 
name3a: GOTO name4 

name4:  <code for c>              ;result in reg1 
        LOAD reg2,[name6]         ;[name6] is the closure for name6 
        GOTO name5 

name5:  JUMP-IF-NIL reg1,name5a 
        RETURN                    ;return the value in reg1 
name5a: GOTO name6 

name6: LOAD reg1,'NIL             ;constant NIL in reg1 
       RETURN

The construction [foo] indicates the creation of a closure for foo in the current environment. This will actually require additional instructions, but we shall ignore the mechanics of this for now since analysis will remove the need for the construction in this case. The fact that the only references to the variables Rl, RZ, and R3 are function calls can be detected and the unnecessary LOAD instructions eliminated. (Once again, this would actually be determined ahead of time, and no LOAD instructions would be generated in the first place. All of this is determined by a general pre-analysis, rather than a peephole post-pass.) Moreover, a GOTO to a tag which immediately follows the GOTO can be eliminated.