AVM: Add TEAL macro expansion support

[michaeldiamant]

Problem

When reading/writing TEAL, the lack of human readable labels and/or ability to concisely group operations can increase the chance of maintainer error.

To address these concerns, the story requests adding macro expansion support for 1+ direct substitution terms separated by semicolon (examples below).

How a human readable label helps - Consider scratch slot ID identification in the following snippet.

// Allocate scratch slots

loop:
 <get next value>
 load 0
 +
 store 0
 load 1
 int 1
 +
 store 1
 <branch is not done>

 load 0
 load 1
 /

Now imagine replacing IDs with a human readable identifier:

// Allocate scratch slots
#define TOTAL 0
#define COUNT 1

loop:
 <get next value>
 load TOTAL
 +
 store TOTAL
 load COUNT
 int 1
 +
 store COUNT
 <branch is not done>

 load TOTAL
 load COUNT
 /

How grouping operations helps - Consider repetitive operations like incrementing by 1. Imagine defining something like:

#define inc int 1; +

int 5
inc

The example leverages #4363 to delimit lines by semi-colon (;) as a way to concisely, visually group statements.

Solution

Dependencies

Urgency