diff --git a/src/cmd/compile/internal/ssa/rewrite_rule_idea.txt b/src/cmd/compile/internal/ssa/rewrite_rule_idea.txt
deleted file mode 100644
index 003e4c02cd..0000000000
--- a/src/cmd/compile/internal/ssa/rewrite_rule_idea.txt
+++ /dev/null
@@ -1,17 +0,0 @@
-idea: pack info about value substructure into an int64
-all values should be encoded as 1<<x, probably byte by byte
-and the hardcoded values should be encoded the same way,
-or as 11111111 for "any"
-then AND together "have" and "want"
-and if zero in any byte (or maybe use popcount < 8?)
-then skip because there is a mismatch
-
-possibble things to include:
-* number of args of v.Args[0], v.Args[1], ...
-* op of v.Args[0]%8, v.Args[1]%8, ...
-
-then can also calculate v.Args[0][0], etc at top and share,
-
-also: cut down commutativity
-
-