From 2481ed4b66171d11523f9ca24a0a48bd770926c6 Mon Sep 17 00:00:00 2001
From: Virgil Dupras <hsoft@hardcoded.net>
Date: Thu, 2 Apr 2020 11:29:23 -0400
Subject: [PATCH] forth: remove dummy.fs

All "stop pings" are now explicitly made at appropriate places. This
fixes a problem I've introduced in the last commit where RAM+ was
unexpectedly part of a stable ABI because of "HERE" usage in dummy.fs.

This system will, anyways, soon change because boot.bin and z80c.bin
will be built during the same process (but there's a bit of retooling
to do before I get there).
---
 emul/Makefile      |  6 +++---
 emul/forth/stop.fs |  2 ++
 forth/dummy.fs     | 13 -------------
 forth/icore.fs     |  5 +++++
 forth/z80c.fs      |  4 ++++
 5 files changed, 14 insertions(+), 16 deletions(-)
 create mode 100644 emul/forth/stop.fs
 delete mode 100644 forth/dummy.fs

diff --git a/emul/Makefile b/emul/Makefile
index cde198c..e055c93 100644
--- a/emul/Makefile
+++ b/emul/Makefile
@@ -7,7 +7,7 @@ AVRABIN = zasm/avra
 SHELLAPPS = zasm ed
 SHELLTGTS = ${SHELLAPPS:%=cfsin/%}
 # Those Forth source files are in a particular order
-FORTHSRCS = core.fs str.fs parse.fs readln.fs fmt.fs z80a.fs dummy.fs
+FORTHSRCS = core.fs str.fs parse.fs readln.fs fmt.fs z80a.fs
 FORTHSRC_PATHS = ${FORTHSRCS:%=../forth/%}
 CFSIN_CONTENTS = $(SHELLTGTS) cfsin/user.h
 OBJS = emul.o libz80/libz80.o
@@ -42,7 +42,7 @@ forth/stage1dbg: forth/stage.c $(OBJS) forth/forth0-bin.h
 	$(CC) -DDEBUG -DBOOT forth/stage.c $(OBJS) -o $@
 
 forth/core.bin: $(FORTHSRC_PATHS) forth/stage1
-	cat $(FORTHSRC_PATHS) | ./forth/stage1 | tee $@ > /dev/null
+	cat $(FORTHSRC_PATHS) ./forth/stop.fs | ./forth/stage1 | tee $@ > /dev/null
 
 forth/forth1.bin: forth/forth0.bin forth/core.bin
 	cat forth/forth0.bin forth/core.bin > $@
@@ -104,7 +104,7 @@ updatebootstrap: $(ZASMBIN)
 .PHONY: fbootstrap
 fbootstrap: forth/stage2
 	cat ./forth/conf.fs ../forth/boot.fs | ./forth/stage2 > forth/boot.bin
-	cat ../forth/dummy.fs ../forth/z80c.fs forth/emul.fs ../forth/icore.fs ../forth/dummy.fs | ./forth/stage2 | tee forth/z80c.bin > /dev/null
+	cat ../forth/z80c.fs forth/emul.fs ../forth/icore.fs | ./forth/stage2 | tee forth/z80c.bin > /dev/null
 
 .PHONY: clean
 clean:
diff --git a/emul/forth/stop.fs b/emul/forth/stop.fs
new file mode 100644
index 0000000..c2777da
--- /dev/null
+++ b/emul/forth/stop.fs
@@ -0,0 +1,2 @@
+(entry) _
+H@ 256 /MOD 2 PC! 2 PC!
diff --git a/forth/dummy.fs b/forth/dummy.fs
deleted file mode 100644
index bb4bae0..0000000
--- a/forth/dummy.fs
+++ /dev/null
@@ -1,13 +0,0 @@
-( When building a compiled dict, always include this unit at
-  the end of it so that Forth knows how to hook LATEST into
-  it. We don't use the word "(entry)" to avoid messing up
-  with icore setup. )
-CREATE _
-H@ 2 - HERE !
-
-( After each dummy word like this, we poke IO port 2 with our
-  current HERE value. The staging executable needs it to know
-  what to dump. )
-
-H@ 256 / 2 PC!
-H@ 2 PC!
diff --git a/forth/icore.fs b/forth/icore.fs
index d0582a9..088202b 100644
--- a/forth/icore.fs
+++ b/forth/icore.fs
@@ -252,3 +252,8 @@
 ':' ' X 4 - C!
 ';' ' Y 4 - C!
 
+( Add dummy entry. we use CREATE because (entry) is, at this
+  point, broken. Adjust H@ durint port 2 ping. )
+CREATE _
+H@ 2 - 256 /MOD 2 PC! 2 PC!
+
diff --git a/forth/z80c.fs b/forth/z80c.fs
index 36f752a..ee00d88 100644
--- a/forth/z80c.fs
+++ b/forth/z80c.fs
@@ -20,6 +20,10 @@
   expected to be defined in platform-specific code.
 )
 
+( dummy entry for dict hook )
+(entry) _
+H@ 256 /MOD 2 PC! 2 PC!
+
 ( a b c -- b c a )
 CODE ROT
     HL POPqq,       ( C )