[O] Run lisp code in macros?

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Is there a way to apply text transformations to arguments in macros?

For example, say that you want to change the first argument to capital letters? 
or transpose the letters of the second argument? 

How would you do that? I imagine you would have to run elisp code, perhaps 
babel is the answer?

Sample code:

#+MACRO: test Change $1 to uppercase, somehow.

* Hello World
{{{test(test phrase)}}}

Desired HTML export:

TEST PHRASE to uppercase, somehow.