diff --git a/compiler/res/prog8lib/prog8_lib.asm b/compiler/res/prog8lib/prog8_lib.asm
index e77778c62..c2ba2fb11 100644
--- a/compiler/res/prog8lib/prog8_lib.asm
+++ b/compiler/res/prog8lib/prog8_lib.asm
@@ -5,33 +5,6 @@
 ;
 ; indent format: TABS, size=8
 
-
-read_byte_from_address_on_stack	.proc
-	; -- read the byte from the memory address on the top of the stack, return in A (stack remains unchanged)
-	; TODO get rid of this by not evaluating the adress onto the stack, but directly into AY or SCRATCH_W2
-		lda  P8ESTACK_LO+1,x
-		ldy  P8ESTACK_HI+1,x
-		sta  P8ZP_SCRATCH_W2
-		sty  P8ZP_SCRATCH_W2+1
-		ldy  #0
-		lda  (P8ZP_SCRATCH_W2),y
-		rts
-		.pend
-
-
-write_byte_to_address_on_stack	.proc
-	; -- write the byte in A to the memory address on the top of the stack (stack remains unchanged)
-	; TODO get rid of this by not evaluating the adress onto the stack, but directly into AY or SCRATCH_W2
-		ldy  P8ESTACK_LO+1,x
-		sty  P8ZP_SCRATCH_W2
-		ldy  P8ESTACK_HI+1,x
-		sty  P8ZP_SCRATCH_W2+1
-		ldy  #0
-		sta  (P8ZP_SCRATCH_W2),y
-		rts
-		.pend
-
-
 neg_b		.proc
 		lda  #0
 		sec
diff --git a/compiler/src/prog8/compiler/target/c64/codegen/assignment/AugmentableAssignmentAsmGen.kt b/compiler/src/prog8/compiler/target/c64/codegen/assignment/AugmentableAssignmentAsmGen.kt
index dcf2e5213..89f20448b 100644
--- a/compiler/src/prog8/compiler/target/c64/codegen/assignment/AugmentableAssignmentAsmGen.kt
+++ b/compiler/src/prog8/compiler/target/c64/codegen/assignment/AugmentableAssignmentAsmGen.kt
@@ -182,10 +182,15 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                         }
                     }
                     else -> {
-                        if(asmgen.options.slowCodegenWarnings)
-                            println("warning: slow stack evaluation used (1): ${memory.addressExpression::class.simpleName} at ${memory.addressExpression.position}") // TODO optimize...
-                        asmgen.translateExpression(memory.addressExpression)  // TODO directly into P8ZP_SCRATCH_W2
-                        asmgen.out("  jsr  prog8_lib.read_byte_from_address_on_stack |  sta  P8ZP_SCRATCH_B1")
+                        asmgen.assignExpressionToVariable(memory.addressExpression, asmgen.asmVariableName("P8ZP_SCRATCH_W2"), DataType.UWORD, target.scope)
+                        asmgen.out("""
+                            lda  P8ZP_SCRATCH_W2
+                            pha
+                            lda  P8ZP_SCRATCH_W2+1
+                            pha
+                            ldy  #0
+                            lda  (P8ZP_SCRATCH_W2),y
+                            sta  P8ZP_SCRATCH_B1""")
                         val zp = CompilationTarget.instance.machine.zeropage
                         when {
                             valueLv != null -> inplaceModification_byte_litval_to_variable(zp.SCRATCH_B1.toHex(), DataType.UBYTE, operator, valueLv.toInt())
@@ -197,7 +202,14 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                             }
                             else -> inplaceModification_byte_value_to_variable(zp.SCRATCH_B1.toHex(), DataType.UBYTE, operator, value)
                         }
-                        asmgen.out("  lda  P8ZP_SCRATCH_B1 |  jsr  prog8_lib.write_byte_to_address_on_stack | inx")
+                        asmgen.out("""
+                            pla
+                            sta  P8ZP_SCRATCH_W2+1
+                            pla
+                            sta  P8ZP_SCRATCH_W2
+                            ldy  #0
+                            lda  P8ZP_SCRATCH_B1
+                            sta  (P8ZP_SCRATCH_W2),y""")
                     }
                 }
             }