From: Ralph Ronnquist <ralph.ronnquist@gmail.com>
Date: Sat, 22 May 2021 11:33:17 +0000 (+1000)
Subject: NUMBER parses negative decimal numbers
X-Git-Url: https://git.rrq.au/?a=commitdiff_plain;h=07e36b49ade19fcf84414fa904542e8fb6b1adc1;p=rrq%2Frrqforth.git

NUMBER parses negative decimal numbers
---

diff --git a/compile.asm b/compile.asm
index 3d5433e..71393bb 100644
--- a/compile.asm
+++ b/compile.asm
@@ -139,42 +139,56 @@ p_create_COPY:
 	pushr rsi
 	pop rcx			; ( -- chars* )
 	pop rsi			; ( -- )
-	xor rdi,rdi
+	xor rdi,rdi		; value
+	mov rbx,1		; sign (byte 0=0 means negative)
+	cmp qword [p_base_DFA],10
+	jne p_number_LOOP
+	cmp byte [rsi],'-'
+	jne p_number_LOOP
+	mov rbx,0
+	inc rsi
+	dec rcx
+	jle p_number_BAD
 p_number_LOOP:
 	dec rcx
 	jl p_number_DONE
+	xor rax,rax		; clearing
 	lodsb
-	mov bl,al		; into bl
-	cmp bl,'0'
+	cmp al,'0'
 	jl p_number_BAD
-	cmp bl,'9'
+	cmp al,'9'
 	jg p_number_ALPHA
-	sub bl,'0'
+	sub al,'0'
 p_number_CONSUME:
+	mov r8,rax
 	mov rax,rdi
-	mul qword [p_base_DFA]
-	add rax,rbx
+	mul qword [p_base_DFA]	; uses rdx:rax
+	add rax,r8
 	mov rdi,rax
 	jmp p_number_LOOP
 p_number_ALPHA:
-	cmp bl,'A'
+	cmp al,'A'
 	jl p_number_BAD
-	cmp bl,'Z'
+	cmp al,'Z'
 	jg p_number_alpha
-	sub bl,'A'-10
+	sub al,'A'-10
 	jmp p_number_CONSUME
 p_number_alpha:
-	cmp bl,'a'
+	cmp al,'a'
 	jl p_number_BAD
-	cmp bl,'z'
+	cmp al,'z'
 	jg p_number_BAD
-	sub bl,'a'-10
+	sub al,'a'-10
 	jmp p_number_CONSUME
 p_number_BAD:
 	push qword 0
 	popr rsi
 	next
 p_number_DONE:
+	cmp rbx,0
+	jne p_numper_POSITIVE
+	neg rdi
+p_numper_POSITIVE:
 	push rdi
 	push qword 1
 	popr rsi
@@ -205,7 +219,7 @@ p_evaluate_stream_NOTWORD:
 	dq p_drop		; ( -- chars* n )
 	dq p_number		; ( -- [ 0 ]/[ v 1 ] )
 	dq p_dup
-	BRANCH 0,p_evaluate_stream_BAD ; branch if 0 on TOP
+	BRANCH 0,p_evaluate_stream_BAD ; branch if 0
 	dq p_drop
 	BRANCH ,p_evaluate_stream_LOOP
 p_evaluate_stream_END: