Enhance the type system to support arbitrary precision integers, which are
important for low-bitwidth inference cases and hardware synthesis targets.

Rename 'int' to 'affineint' to avoid confusion between "the integers" and "the int
type".

PiperOrigin-RevId: 202751508
diff --git a/test/IR/parser-errors.mlir b/test/IR/parser-errors.mlir
index 408fe13..fb4c2cc 100644
--- a/test/IR/parser-errors.mlir
+++ b/test/IR/parser-errors.mlir
@@ -6,7 +6,7 @@
 ; Check different error cases.
 ; -----
 
-extfunc @illegaltype(i42) ; expected-error {{expected type}}
+extfunc @illegaltype(i) ; expected-error {{expected type}}
 
 ; -----
 
@@ -19,7 +19,7 @@
 
 ; -----
 
-extfunc missingsigil() -> (i1, int, f32) ; expected-error {{expected a function identifier like}}
+extfunc missingsigil() -> (i1, affineint, f32) ; expected-error {{expected a function identifier like}}
 
 
 ; -----
@@ -75,3 +75,9 @@
   ""()   ; expected-error {{empty operation name is invalid}}
   return
 }
+
+; -----
+
+extfunc @illegaltype(i0) ; expected-error {{invalid integer width}}
+
+