index register

TODO.md

@@ -1,5 +1,8 @@
-- it would be cool for the generated code writer to go to files
-  - and make the +1 methods optional (for when it is at max)
+- normalize A, X, Y, ZP, and GP to "registers", allocated by an allocator
+  - X and Y are also index registers, so slightly special
+    - unit test: what if a for loop is three deep? the outermost loop must be a memory register
+- it would be cool for the 22-tuple Scala code generator code writer to go to files
+  - and make the +1 methods optional (for when it is at max == 22)
 - the payload/`xs` of a program should be an ADT of either chunks or one instruction
   - where a chunk is just many instructions
   - and an instruction already has the value X with its encoder, but chooses an eternal mode

firepower-core/src/test/scala/com/htmlism/firepower/core/RegisterAllocatorSuite.scala

@@ -0,0 +1,19 @@
+package com.htmlism.firepower.core
+
+import weaver.FunSuite
+
+object RegisterAllocatorSuite extends FunSuite:
+  test("cam allocate registers"):
+    expect.eql("TODO", "TODO")
+
+  test("A register can be allocated to a single byte width"):
+    expect.eql("TODO", "TODO")
+
+  test("Allocates CPU registers first, then zero page, then global"):
+    expect.eql("TODO", "TODO")
+
+  test("A single-byte register can specifically be an index register"):
+    expect.eql("TODO", "TODO")
+
+  test("A register can be allocated to a two-byte width, always a memory register"):
+    expect.eql("TODO", "TODO")