kernel/core.asm

@@ -27,29 +27,34 @@ addDE:
 noop:				; piggy backing on the first "ret" we have
 	ret
 
-; copy (HL) into DE, then exchange the two, utilising the optimised HL instructions. 
+; copy (DE) into DE, little endian style (addresses in z80 are always have
-; ld must be done little endian, so least significant byte first.
+; their LSB before their MSB)
-intoHL:
+intoDE:
-	push 	de
+	push	af
-	ld 	e, (hl)
+	ld	a, (de)
-	inc 	hl
+	inc	de
-	ld 	d, (hl)
+	ex	af, af'
-	ex 	de, hl
+	ld	a, (de)
-	pop 	de
+	ld	d, a
+	ex	af, af'
+	ld	e, a
+	pop	af
 	ret
 
-intoDE:
+intoHL:
-	ex 	de, hl
+	push	de
-	call 	intoHL
+	ex	de, hl
-	ex 	de, hl		; de preserved by intoHL, so no push/pop needed
+	call	intoDE
+	ex	de, hl
+	pop	de
 	ret
 
 intoIX:
-	push 	ix
+	push	de
-	ex 	(sp), hl	;swap hl with ix, on the stack
+	push	ix \ pop de
-	call 	intoHL
+	call	intoDE
-	ex 	(sp), hl	;restore hl from stack
+	push	de \ pop ix
-	pop 	ix
+	pop	de
 	ret
 
 ; add the value of A into HL

tools/tests/zasm/runtests.sh

@@ -1,4 +1,4 @@
-#!/usr/bin/env bash
+#!/bin/sh
 
 set -e
 

tools/zasm.sh

@@ -1,11 +1,7 @@
-#!/usr/bin/env bash
+#!/bin/sh
-
-# readlink -f doesn't work with macOS's implementation
-# so, if we can't get readlink -f to work, try python with a realpath implementation
-ABS_PATH=$(readlink -f "$0" || python -c "import sys, os; print(os.path.realpath('$0'))")
 
 # wrapper around ./emul/zasm/zasm that prepares includes CFS prior to call
-DIR=$(dirname "${ABS_PATH}")
+DIR=$(dirname $(readlink -f "$0"))
 ZASMBIN="${DIR}/emul/zasm/zasm"
 CFSPACK="${DIR}/cfspack/cfspack"
 INCCFS=$(mktemp)