diff --git a/src/vm_s390x.dasc b/src/vm_s390x.dasc
index f58d3690..d1cf9524 100644
--- a/src/vm_s390x.dasc
+++ b/src/vm_s390x.dasc
@@ -103,10 +103,26 @@
 |.macro saveregs
 |  stmg r6, r15, SAVE_GPRS_P
 |  lay sp, -CFRAME_SPACE(sp)	// Allocate stack frame.
-|  // f8-f15 are also callee-save but are not currently used in the interpreter.
+|  // TODO: save backchain?
+|  std f8, SAVE_FPR8		// f8-f15 are callee-saved.
+|  std f9, SAVE_FPR9
+|  std f10, SAVE_FPR10
+|  std f11, SAVE_FPR11
+|  std f12, SAVE_FPR12
+|  std f13, SAVE_FPR13
+|  std f14, SAVE_FPR14
+|  std f15, SAVE_FPR15
 |.endmacro
 |
 |.macro restoreregs
+|  ld f8, SAVE_FPR8		// f8-f15 are callee-saved.
+|  ld f9, SAVE_FPR9
+|  ld f10, SAVE_FPR10
+|  ld f11, SAVE_FPR11
+|  ld f12, SAVE_FPR12
+|  ld f13, SAVE_FPR13
+|  ld f14, SAVE_FPR14
+|  ld f15, SAVE_FPR15
 |  lmg r6, r15, SAVE_GPRS	// Restores the stack pointer.
 |.endmacro
 |