riscv64: implement Linuxthreads, from sorear

extra/Configs/Config.in

@@ -164,6 +164,7 @@ config TARGET_ARCH_BITS
 	default 64 if TARGET_aarch64
 	default 64 if TARGET_ia64
 	default 64 if TARGET_powerpc64
+	default 64 if TARGET_riscv64
 	default 64 if TARGET_sparc64
 	default 64 if TARGET_x86_64
 	default 64 if TARGET_kvx
@@ -593,7 +594,6 @@ config UCLIBC_HAS_LINUXTHREADS
 	# linuxthreads need nanosleep()
 	select UCLIBC_HAS_REALTIME
 	depends on !TARGET_aarch64 && \
-		   !TARGET_riscv64 && \
 		   !TARGET_riscv32 && \
 		   !TARGET_metag
 	help

libc/sysdeps/linux/riscv64/jmpbuf-unwind.h

@@ -23,8 +23,8 @@
 
 /* Test if longjmp to JMPBUF would unwind the frame
    containing a local variable at ADDRESS.  */
-#define _JMPBUF_UNWINDS(jmpbuf, address, demangle)		\
-  ((void *) (address) < (void *) demangle ((jmpbuf)[0].__sp))
+#define _JMPBUF_UNWINDS(jmpbuf, address)		\
+  ((void *) (address) < (void *) ((jmpbuf)[0].__sp))
 
 #define _JMPBUF_CFA_UNWINDS_ADJ(_jmpbuf, _context, _adj) \
   _JMPBUF_UNWINDS_ADJ (_jmpbuf, (void *) _Unwind_GetCFA (_context), _adj)
@@ -33,9 +33,6 @@ static inline uintptr_t __attribute__ ((unused))
 _jmpbuf_sp (__jmp_buf regs)
 {
   uintptr_t sp = regs[0].__sp;
-#ifdef PTR_DEMANGLE
-  PTR_DEMANGLE (sp);
-#endif
   return sp;
 }
 

libpthread/linuxthreads/manager.c

@@ -455,7 +455,7 @@ static int pthread_allocate_stack(const pthread_attr_t *attr,
        * the kernel chokes on a non-aligned stack frame. Choose the lower
        * available word boundary.
        */
-      new_thread = ((pthread_descr) ((int)(new_thread_bottom + stacksize) & -sizeof(void*))) - 1;
+      new_thread = ((pthread_descr) ((long)(new_thread_bottom + stacksize) & -sizeof(void*))) - 1;
       guardaddr = NULL;
       guardsize = 0;
 

libpthread/linuxthreads/sysdeps/riscv64/pt-machine.h

@@ -0,0 +1,61 @@
+/*
+ * Licensed under the LGPL v2.1 or later, see the file COPYING.LIB in this tarball.
+ */
+
+#ifndef _PT_MACHINE_H
+#define _PT_MACHINE_H   1
+#include <features.h>
+
+#ifndef PT_EI
+# define PT_EI __extern_always_inline
+#endif
+
+#define HAS_COMPARE_AND_SWAP
+PT_EI int
+__compare_and_swap (long int *p, long int oldval, long int newval)
+{
+  long int ret, temp;
+
+  __asm__ __volatile__
+    ("/* Inline compare & swap */\n"
+     "1:\n\t"
+     "lr.d      %1,%2\n\t"
+     "li        %0,0\n\t"
+     "bne       %1,%3,2f\n\t"
+     "li        %0,1\n\t"
+     "sc.d      %1,%4,%2\n\t"
+     "bnez      %1,1b\n"
+     "2:\n\t"
+     "/* End compare & swap */"
+     : "=&r" (ret), "=&r" (temp), "+A" (*p)
+     : "r" (oldval), "r" (newval)
+     : "memory");
+
+  return ret;
+}
+
+extern long int testandset (int *spinlock);
+
+PT_EI long int
+testandset (int *spinlock)
+{
+        unsigned int old = 1;
+        int tmp = 1;
+
+        __asm__ __volatile__ (
+        "amoswap.w %0, %2, %1"
+        : "=r" (old), "+A" (*spinlock)
+        : "r" (tmp)
+        : "memory");
+
+        return old;
+}
+
+/* Get some notion of the current stack.  Need not be exactly the top
+   of the stack, just something somewhere in the current frame.  */
+#define CURRENT_STACK_FRAME  stack_pointer
+register char * stack_pointer __asm__ ("sp");
+
+#else
+#error PT_MACHINE already defined
+#endif /* pt-machine.h */