From 5e1475bc1afeecd3bd9388cac34d937ea67c2a68 Mon Sep 17 00:00:00 2001
From: Ralph Ronnquist <ralph.ronnquist@gmail.com>
Date: Sat, 22 May 2021 21:36:45 +1000
Subject: [PATCH] simplify EMIT and add "dot" for number display

---
 stdio.asm | 46 ++++++++++++++++++++++++++++++++++++++--------
 1 file changed, 38 insertions(+), 8 deletions(-)

diff --git a/stdio.asm b/stdio.asm
index 5767d8b..a6cf512 100644
--- a/stdio.asm
+++ b/stdio.asm
@@ -32,7 +32,7 @@
 ;;; * block address
 ;;; * -1
 ;;; * size of block
-;;; * current read position (starts at 8 = after block size)
+;;; * current read position
 
 	WORD p_stream,'STREAM',fasm
 	;; ( fd size -- addr ) or ( block -1 -- addr )
@@ -187,19 +187,17 @@ p_read_word_nomore:
 	popr rsi
 	next
 
-p_emit_buffer:	dq 0
-	
 	WORD p_emit,'EMIT',fasm
 	;; ( c -- )
 	;; Write byte to stdout
 	pushr rsi
-	pop rax
-	mov [p_emit_buffer],al
+	mov rax,rsp
 	push 1
-	push p_emit_buffer
+	push rax
 	push 1
 	DOFORTH sys_write
-	pop rax
+	pop rax			; ignore return value
+	pop rax			; drop input data
         popr rsi
 	next
 
@@ -212,4 +210,36 @@ p_emit_buffer:	dq 0
 	;; ( -- c )
 	;; Pushes a space character on the stack
 	dq 10
-	
+
+	WORD p_digits,'DIGITS',dovariable
+	db '0123456789abcdef'
+
+	WORD p_dot,'.',fasm
+	;; ( v -- )
+	;; Print TOP value as unsigned BASE integer
+	pushr rsi
+	mov rax,qword [rsp]
+	cmp rax,0
+	jge p_dot_positive
+	cmp qword [p_base_DFA],10
+	jne p_dot_positive
+	push '-'
+	DOFORTH p_emit
+	mov rax,qword [rsp]
+	neg rax
+p_dot_positive:
+	xor rdx,rdx
+	div qword [p_base_DFA]	; rdx:rax / BASE => q=rax, r=rdx
+	mov qword [rsp],rdx 
+	cmp rax,0
+	je p_dot_remainder
+	push rax
+	DOFORTH p_dot
+p_dot_remainder:
+	pop rdx
+	xor rax,rax
+	mov al,[p_digits_DFA+rdx]
+	push rax
+	DOFORTH p_emit
+	popr rsi
+	next
-- 
2.39.2