From: cuz <cuz@b7a2c559-68d2-44c3-8de9-860c34a00d81>
Date: Thu, 19 Apr 2001 06:46:01 +0000 (+0000)
Subject: Squeezed a few cycles/bytes out of tolower and toupper.
X-Git-Tag: V2.12.0~2873
X-Git-Url: https://git.sur5r.net/?a=commitdiff_plain;h=dccc89edaebdf39d8a3f16a96f2816dee472a5fb;p=cc65

Squeezed a few cycles/bytes out of tolower and toupper.


git-svn-id: svn://svn.cc65.org/cc65/trunk@690 b7a2c559-68d2-44c3-8de9-860c34a00d81
---

diff --git a/libsrc/common/tolower.s b/libsrc/common/tolower.s
index 5ecc92f09..fa03146b0 100644
--- a/libsrc/common/tolower.s
+++ b/libsrc/common/tolower.s
@@ -10,13 +10,10 @@
 _tolower:
        	tay			; Get C into Y
 	lda	__ctype,y	; Get character classification
-	and	#$02		; Is this an upper case char?
-	beq	L1		; Jump if no
+	lsr	a
+	lsr	a		; Get bit 1 (upper case char) into carry
 	tya			; Get char back into A
-       	sec
-	sbc	__cdiff		; make lower case char
-       	rts			; CC are set
-
-L1:	tya			; Get char back into A
-	rts			; CC are set
+       	bcc    	L9		; Jump if no upper case char
+   	sbc	__cdiff		; make lower case char (carry already set)
+L9:    	rts	  		; CC are set
 
diff --git a/libsrc/common/toupper.s b/libsrc/common/toupper.s
index 43ff0812d..ab7711cb2 100644
--- a/libsrc/common/toupper.s
+++ b/libsrc/common/toupper.s
@@ -10,13 +10,10 @@
 _toupper:
 	tay			; Get c into Y
 	lda	__ctype,y	; Get character classification
-	and	#$01		; Mask lower char bit
-	beq	L1		; Jump if not lower char
+	lsr	a		; Get bit 0 (lower char) into carry
 	tya			; Get C back into A
+       	bcc    	L9		; Jump if not lower char
        	clc
 	adc	__cdiff		; make upper case char
-	rts			; CC are set
-
-L1:	tya	     		; Get C back
-	rts			; CC are set
+L9:	rts	  		; CC are set