ir3/bisect: fix off-by-one issues while bisecting

Fixes two separate issues:
- Getting stuck when ending up with a list of 2 ids;
- Removing a potential bad id.

Signed-off-by: Job Noorman <jnoorman@igalia.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/38993>

src/freedreno/ir3/ir3_shader_bisect.py

@@ -32,7 +32,7 @@ def bisect(args):
 
     while len(ids) > 1:
         lo_id = 0
-        hi_id = len(ids) // 2
+        hi_id = len(ids) // 2 - 1
         lo = ids[lo_id]
         hi = ids[hi_id]
         extra_env = {
@@ -44,7 +44,7 @@ def bisect(args):
         if was_good():
             del ids[lo_id:hi_id + 1]
         else:
-            del ids[hi_id:]
+            del ids[hi_id + 1:]
 
     print(ids)