libroot/riscv64: minor riscv64 fixes

Change-Id: I96b604aabe18307d7376473b8d9cd50eccb537d1
Reviewed-on: https://review.haiku-os.org/c/haiku/+/4709
Reviewed-by: Alex von Gluck IV <kallisti5@unixzen.com>

src/system/libroot/os/arch/riscv64/Jamfile

@@ -22,6 +22,8 @@ for architectureObject in [ MultiArchSubDirSetup riscv64 ] {
 			time.cpp
 			thread.cpp
 
+			cachectl.cpp
+
 			generic_atomic.cpp
 			generic_stack_trace.cpp
 			generic_system_time_nsecs.cpp

src/system/libroot/os/arch/riscv64/cachectl.cpp

@@ -0,0 +1,11 @@
+/*
+ * Copyright 2021, Haiku, Inc.
+ * Distributed under the terms of the MIT License.
+ */
+
+
+extern "C" void
+__riscv_flush_icache(void *start, void *end, unsigned long int flags)
+{
+	__asm__ volatile ("fence.i");
+}

src/system/libroot/posix/glibc/stdlib/Jamfile

@@ -32,6 +32,7 @@ for architectureObject in [ MultiArchSubDirSetup ] {
 			l64a.c
 			lcong48.c
 			lcong48_r.c
+			longlong.c
 			lrand48.c
 			lrand48_r.c
 			mrand48.c

src/system/libroot/posix/glibc/stdlib/longlong.c

@@ -0,0 +1,17 @@
+/*
+ * Copyright 2021, Haiku, Inc.
+ * Distributed under the terms of the MIT License.
+ */
+
+
+const char __clz_tab[256] =
+{
+	0,1,2,2,3,3,3,3,4,4,4,4,4,4,4,4,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,
+	6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
+	7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
+	7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
+	8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
+	8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
+	8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
+	8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8
+};