diff --git a/riscV/TargetPrinter.ml b/riscV/TargetPrinter.ml
index f4cea9dda..1ca13ff36 100644
--- a/riscV/TargetPrinter.ml
+++ b/riscV/TargetPrinter.ml
@@ -522,10 +522,17 @@ module Target : TARGET =
                     freg rd label lbl comment (camlfloat_of_coqfloat32 f)
       | Pbtbl(r, tbl) ->
          let lbl = new_label() in
-         fprintf oc "%s jumptable [ " comment;
+         fprintf oc "%s pseudoinstr btbl [ " comment;
          List.iter (fun l -> fprintf oc "%a " print_label l) tbl;
          fprintf oc "]\n";
-         fprintf oc "	sll	x5, %a, 2\n" ireg r;
+         if Archi.ptr64 then begin
+           (* Zero-extend [r] (a 32-bit integer) to 64-bit
+              and multiply it by 4. *)
+           fprintf oc "	sll	x5, %a, 32\n" ireg r;
+           fprintf oc "	srl	x5, x5, 30\n"
+         end else begin
+           fprintf oc "	sll	x5, %a, 2\n" ireg r
+         end;
          fprintf oc "	lla	x31, %a\n" label lbl;
          fprintf oc "	add	x5, x31, x5\n";
          fprintf oc "	lw	x5, 0(x5)\n";
diff --git a/test b/test
index 27899bbab..4df7312a3 160000
--- a/test
+++ b/test
@@ -1 +1 @@
-Subproject commit 27899bbabecd10148c2a2f1b3b62f55b8edca556
+Subproject commit 4df7312a3ff71037c20856dfeff727e36c77848e
diff --git a/x86/TargetPrinter.ml b/x86/TargetPrinter.ml
index 3bc863f7d..397ebe78b 100644
--- a/x86/TargetPrinter.ml
+++ b/x86/TargetPrinter.ml
@@ -752,7 +752,9 @@ module Target(System: SYSTEM):TARGET =
             let (tmp1, tmp2) =
               if r = RAX then (RDX, RAX) else (RAX, RDX) in
             fprintf oc "	leaq	%a(%%rip), %a\n" label l ireg tmp1;
-            fprintf oc "	movslq	(%a, %a, 4), %a\n" ireg tmp1 ireg r ireg tmp2;
+            (* Normalize r to 32-bit unsigned *)
+            fprintf oc "	movl	%a, %a\n" ireg32 r ireg32 tmp2;
+            fprintf oc "	movslq	(%a, %a, 4), %a\n" ireg tmp1 ireg tmp2 ireg tmp2;
             fprintf oc "	addq	%a, %a\n" ireg tmp2 ireg tmp1;
             fprintf oc "	jmp	*%a\n" ireg tmp1
           end else begin