From 13be3ba3ef3598db220762a9bb4a24a280c638b1 Mon Sep 17 00:00:00 2001
From: cuz <cuz@b7a2c559-68d2-44c3-8de9-860c34a00d81>
Date: Fri, 1 Dec 2000 17:25:07 +0000
Subject: [PATCH] Rewrote fprintf in assembler

git-svn-id: svn://svn.cc65.org/cc65/trunk@513 b7a2c559-68d2-44c3-8de9-860c34a00d81
---
 libsrc/common/.cvsignore |  1 -
 libsrc/common/Makefile   |  3 +-
 libsrc/common/fprintf.c  | 26 ---------------
 libsrc/common/fprintf.s  | 70 ++++++++++++++++++++++++++++++++++++++++
 4 files changed, 72 insertions(+), 28 deletions(-)
 delete mode 100644 libsrc/common/fprintf.c
 create mode 100644 libsrc/common/fprintf.s

diff --git a/libsrc/common/.cvsignore b/libsrc/common/.cvsignore
index 53109108e..1ebdbe1d6 100644
--- a/libsrc/common/.cvsignore
+++ b/libsrc/common/.cvsignore
@@ -12,7 +12,6 @@ fgetc.s
 fgetpos.s
 fgets.s
 fopen.s
-fprintf.s
 fputc.s
 fputs.s
 fread.s
diff --git a/libsrc/common/Makefile b/libsrc/common/Makefile
index b00dd0837..a5e668664 100644
--- a/libsrc/common/Makefile
+++ b/libsrc/common/Makefile
@@ -11,7 +11,7 @@
 %.o:	%.s
 	@$(AS) -g -o $@ $(AFLAGS) $<
 
-C_OBJS = fclose.o fgets.o fprintf.o calloc.o _fopen.o\
+C_OBJS = fclose.o fgets.o calloc.o _fopen.o\
 	 fputs.o fread.o fwrite.o gets.o realloc.o bsearch.o strxfrm.o\
 	 _hextab.o fdopen.o strtok.o\
 	 _afailed.o fopen.o fgetc.o fputc.o puts.o gets.o perror.o getchar.o\
@@ -35,6 +35,7 @@ S_OBJS = 	_fdesc.o	\
 		cprintf.o	\
 		errno.o		\
 		fmisc.o 	\
+		fprintf.o	\
 		free.o		\
 		getcpu.o	\
 		isalnum.o	\
diff --git a/libsrc/common/fprintf.c b/libsrc/common/fprintf.c
deleted file mode 100644
index 010180bf8..000000000
--- a/libsrc/common/fprintf.c
+++ /dev/null
@@ -1,26 +0,0 @@
-/*
- * fprintf.c
- *
- * Ullrich von Bassewitz, 11.08.1998
- */
-
-
-
-#include <stdarg.h>
-#include <stdio.h>
-
-
-
-int fprintf (FILE* /*F*/, const char* format, ...)
-{
-    va_list ap;
-    va_start (ap, format);
-
-    /* Do formatting and output. Since we know, that va_end is empty, we don't
-     * call it here, saving an extra variable and some code.
-     */
-    return vfprintf ((FILE*) va_fix (ap, 1), (char*) va_fix (ap, 2), ap);
-}
-
-
-
diff --git a/libsrc/common/fprintf.s b/libsrc/common/fprintf.s
new file mode 100644
index 000000000..318f68576
--- /dev/null
+++ b/libsrc/common/fprintf.s
@@ -0,0 +1,70 @@
+;
+; int printf (const char* Format, ...);
+;
+; Ullrich von Bassewitz, 1.12.2000
+;
+
+	.export	      	_fprintf
+	.import		pushax, addysp, subysp, _vfprintf
+	.importzp	sp, ptr1
+
+	.macpack	generic
+
+; ----------------------------------------------------------------------------
+; Data
+
+.bss
+
+ParamSize: 	.res  	1		; Number of parameter bytes
+
+; ----------------------------------------------------------------------------
+; Code
+
+.code
+
+
+_fprintf:
+  	sty	ParamSize		; Number of param bytes passed in Y
+
+; We have to push f and format, both in the order they already have on stack.
+; To make this somewhat more efficient, we will create space on the stack and
+; the do a copy of the complete block instead of pushing each parameter
+; separately. Since the size of the arguments passed is the same as the size
+; of the fixed arguments, this will allow us to calculate the pointer to the
+; fixed size arguments easier (they're just ParamSize bytes away).
+
+	ldy	#4
+	jsr	subysp
+
+; Calculate a pointer to the Format argument
+
+	lda	ParamSize
+	add	sp
+	sta	ptr1
+	ldx	sp+1
+	bcc	@L1
+	inx
+@L1:	stx	ptr1+1
+
+; Now copy both, f and format
+
+	ldy	#4-1
+@L2:	lda	(ptr1),y
+	sta	(sp),y
+	dey
+	bpl	@L2
+
+; Load va_list (last and __fastcall__ parameter to vfprintf)
+
+	lda    	ptr1
+	ldx    	ptr1+1
+
+; Call vfprintf
+
+	jsr	_vfprintf
+
+; Cleanup the stack. We will return what we got from vfprintf
+
+	ldy	ParamSize
+	jmp	addysp
+