newlib, glibc: fix memcpy bug

h/t Martin Maas

1 files changed, 25 insertions, 17 deletions

diff --git a/newlib/newlib/libc/machine/riscv/memcpy.c b/newlib/newlib/libc/machine/riscv/memcpy.c
index 12618eb..56349da 100644
--- a/newlib/newlib/libc/machine/riscv/memcpy.c
+++ b/newlib/newlib/libc/machine/riscv/memcpy.c
@@ -15,7 +15,7 @@ void* memcpy(void* aa, const void* bb, size_t n)
   uintptr_t msk = sizeof(long)-1;
   if (__builtin_expect(((uintptr_t)a & msk) != ((uintptr_t)b & msk) || n < sizeof(long), 0))
   {
-foo:
+small:
     if (__builtin_expect(a < end, 1))
       while (a < end)
         BODY(a, b, char);
@@ -26,34 +26,42 @@ foo:
     while ((uintptr_t)a & msk)
       BODY(a, b, char);
 
-  long* __restrict__ la = (long*)a;
-  const long* __restrict__ lb = (const long*)b;
+  long* la = (long*)a;
+  const long* lb = (const long*)b;
   long* lend = (long*)((uintptr_t)end & ~msk);
 
   if (__builtin_expect(la < lend-8, 0))
   {
     while (la < lend-8)
     {
-      *la++ = *lb++;
-      *la++ = *lb++;
-      *la++ = *lb++;
-      *la++ = *lb++;
-      *la++ = *lb++;
-      *la++ = *lb++;
-      *la++ = *lb++;
-      *la++ = *lb++;
-      *la++ = *lb++;
+      long b0 = *lb++;
+      long b1 = *lb++;
+      long b2 = *lb++;
+      long b3 = *lb++;
+      long b4 = *lb++;
+      long b5 = *lb++;
+      long b6 = *lb++;
+      long b7 = *lb++;
+      long b8 = *lb++;
+      *la++ = b0;
+      *la++ = b1;
+      *la++ = b2;
+      *la++ = b3;
+      *la++ = b4;
+      *la++ = b5;
+      *la++ = b6;
+      *la++ = b7;
+      *la++ = b8;
     }
-    if (la == lend)
-      goto bar;
   }
 
-  do BODY(la, lb, long) while (la < lend);
+  while (la < lend)
+    BODY(la, lb, long);
 
-bar:
+maybe_done:
   a = (char*)la;
   b = (const char*)lb;
   if (__builtin_expect(a < end, 0))
-    goto foo;
+    goto small;
   return aa;
 }