Note there is a way to do negative offsets.

diff --git a/src/compiler/machines/aarch64/rules3.scm b/src/compiler/machines/aarch64/rules3.scm
index ff7b3970564092c62a335619ac0b9a7167c3e18c..37f7fd8d70d24023d18a4fc09c098da2996801c5 100644 (file)
--- a/src/compiler/machines/aarch64/rules3.scm
+++ b/src/compiler/machines/aarch64/rules3.scm
@@ -92,6 +92,8 @@ USA.
 (define (entry->pc pc entry)
   ;; XXX Would be nice to skip the SUB, but LDR doesn't have a signed
   ;; offset without pre/post-increment.
+  ;;
+  ;; XXX Oops -- yes we can: LDUR.
   (LAP (SUB X ,pc ,entry (&U 8))
        (LDR X ,pc ,pc)
        (ADD X ,pc ,pc ,entry)))