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Added EXIT entry point

ceriel 32 年之前
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66ebea6cfe
共有 1 个文件被更改,包括 7 次插入0 次删除
  1. 7 0
      mach/6500/libmon/head_em.s

+ 7 - 0
mach/6500/libmon/head_em.s

@@ -9,6 +9,7 @@
 .define RETSIZE, TRAPVAL, STACK, BRANCH
 .define RETSIZE, TRAPVAL, STACK, BRANCH
 .define start, Push, Pop, STACKTh, STACKTl
 .define start, Push, Pop, STACKTh, STACKTl
 .define F_DUM
 .define F_DUM
+.define EXIT
 .sect .zero
 .sect .zero
 .sect .text
 .sect .text
 .sect .rom
 .sect .rom
@@ -186,6 +187,12 @@ start:
 	jsr OSBYTE	! input only from R423
 	jsr OSBYTE	! input only from R423
 	rts
 	rts
 
 
+EXIT:
+	ldx STACK	! load stackpointer
+	dex
+	dex		! adjust
+	txs		! reset hardware stackpointer
+	rts
 
 
 ! The subroutine Push pushes the registerpair AX onto the stack.
 ! The subroutine Push pushes the registerpair AX onto the stack.