From f88b85a31cd1e02e9efa52fdacfc004152a88aa3 Mon Sep 17 00:00:00 2001
From: "Gabriel L. Somlo" <gsomlo@gmail.com>
Date: Tue, 4 Jun 2019 14:42:54 -0400
Subject: [PATCH] software/libbase: memcpy: simple, arch-width agnostic
 implementation

Remove optimizations targeted specifically at rv32 architecture,
allowing memcpy to work on all word sizes.

Since this is "only" the BIOS, it is also arguably better to
optimize for size rather than performance, given that control
will be quickly handed over to some other program being loaded.

Signed-off-by: Gabriel Somlo <gsomlo@gmail.com>
---
 litex/soc/software/libbase/libc.c | 69 +++----------------------------
 1 file changed, 5 insertions(+), 64 deletions(-)

diff --git a/litex/soc/software/libbase/libc.c b/litex/soc/software/libbase/libc.c
index f28c4207e..be48cf651 100644
--- a/litex/soc/software/libbase/libc.c
+++ b/litex/soc/software/libbase/libc.c
@@ -293,71 +293,12 @@ void *memset(void *s, int c, size_t count)
  */
 void *memcpy(void *to, const void *from, size_t n)
 {
-	void *xto = to;
-	size_t temp;
+	char *tmp = to;
+	const char *s = from;
 
-	if(!n)
-		return xto;
-	if((long)to & 1) {
-		char *cto = to;
-		const char *cfrom = from;
-		*cto++ = *cfrom++;
-		to = cto;
-		from = cfrom;
-		n--;
-	}
-	if((long)from & 1) {
-		char *cto = to;
-		const char *cfrom = from;
-		for (; n; n--)
-			*cto++ = *cfrom++;
-		return xto;
-	}
-	if(n > 2 && (long)to & 2) {
-		short *sto = to;
-		const short *sfrom = from;
-		*sto++ = *sfrom++;
-		to = sto;
-		from = sfrom;
-		n -= 2;
-	}
-	if((long)from & 2) {
-		short *sto = to;
-		const short *sfrom = from;
-		temp = n >> 1;
-		for (; temp; temp--)
-			*sto++ = *sfrom++;
-		to = sto;
-		from = sfrom;
-		if(n & 1) {
-			char *cto = to;
-			const char *cfrom = from;
-			*cto = *cfrom;
-		}
-		return xto;
-	}
-	temp = n >> 2;
-	if(temp) {
-		long *lto = to;
-		const long *lfrom = from;
-		for(; temp; temp--)
-			*lto++ = *lfrom++;
-		to = lto;
-		from = lfrom;
-	}
-	if(n & 2) {
-		short *sto = to;
-		const short *sfrom = from;
-		*sto++ = *sfrom++;
-		to = sto;
-		from = sfrom;
-	}
-	if(n & 1) {
-		char *cto = to;
-		const char *cfrom = from;
-		*cto = *cfrom;
-	}
-	return xto;
+	while (n--)
+		*tmp++ = *s++;
+	return to;
 }
 
 /**