patch-2.3.43 linux/arch/ia64/lib/clear_page.S

• Lines: 43
• Date: Sun Feb 6 18:42:40 2000
• Orig file: v2.3.42/linux/arch/ia64/lib/clear_page.S
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.3.42/linux/arch/ia64/lib/clear_page.S linux/arch/ia64/lib/clear_page.S
@@ -0,0 +1,42 @@
+/*
+ *
+ * Optimized version of the standard clearpage() function
+ *
+ * Based on comments from ddd. Try not to overflow the write buffer.
+ *
+ * Inputs:
+ *	in0:	address of page
+ * 
+ * Output:
+ * 	none
+ *
+ * Copyright (C) 1999 Hewlett-Packard Co
+ * Copyright (C) 1999 Stephane Eranian <eranian@hpl.hp.com>
+ * Copyright (C) 1999 David Mosberger-Tang <davidm@hpl.hp.com>
+ */
+#include <asm/page.h>
+
+	.text
+	.psr abi64
+	.psr lsb
+	.lsb
+
+	.align 32
+	.global clear_page
+	.proc clear_page
+clear_page:
+	alloc r11=ar.pfs,1,0,0,0
+	mov r16=ar.lc		// slow
+	mov r17=PAGE_SIZE/32-1	// -1 = repeat/until
+	;;
+	adds r18=16,in0
+	mov ar.lc=r17
+	;;
+1:	stf.spill.nta [in0]=f0,32
+	stf.spill.nta [r18]=f0,32
+	br.cloop.dptk.few 1b
+	;;
+	mov ar.lc=r16		// restore lc
+	br.ret.sptk.few rp
+
+	.endp clear_page