X-Git-Url: https://git.liburcu.org/?p=urcu.git;a=blobdiff_plain;f=include%2Furcu%2Fuatomic%2Fs390.h;h=d7d545ad8f869ede493edef727233d7e9edc42ad;hp=62561e000224ccb4c71e244a239eab5ac730f70b;hb=713234991cce999c376345400f9367f1e2317076;hpb=6893800a4d1cc14dff0395ddcd660a5138db183d

diff --git a/include/urcu/uatomic/s390.h b/include/urcu/uatomic/s390.h
index 62561e0..d7d545a 100644
--- a/include/urcu/uatomic/s390.h
+++ b/include/urcu/uatomic/s390.h
@@ -61,10 +61,15 @@ extern "C" {
 
 #endif /* !COMPILER_HAVE_SHORT_MEM_OPERAND */
 
-struct __uatomic_dummy {
-	unsigned long v[10];
-};
-#define __hp(x)	((struct __uatomic_dummy *)(x))
+/*
+ * The __hp() macro casts the void pointer @x to a pointer to a structure
+ * containing an array of char of the specified size. This allows passing the
+ * @addr arguments of the following inline functions as "m" and "+m" operands
+ * to the assembly. The @size parameter should be a constant to support
+ * compilers such as clang which do not support VLA.
+ */
+
+#define __hp(size, x)	((struct { char v[size]; } *)(x))
 
 /* xchg */
 
@@ -79,8 +84,8 @@ unsigned long _uatomic_exchange(volatile void *addr, unsigned long val, int len)
 		__asm__ __volatile__(
 			"0:	cs %0,%2," MEMOP_REF(%3) "\n"
 			"	brc 4,0b\n"
-			: "=&r" (old_val), MEMOP_OUT (__hp(addr))
-			: "r" (val), MEMOP_IN (__hp(addr))
+			: "=&r" (old_val), MEMOP_OUT (__hp(4, addr))
+			: "r" (val), MEMOP_IN (__hp(4, addr))
 			: "memory", "cc");
 		return old_val;
 	}
@@ -92,8 +97,8 @@ unsigned long _uatomic_exchange(volatile void *addr, unsigned long val, int len)
 		__asm__ __volatile__(
 			"0:	csg %0,%2," MEMOP_REF(%3) "\n"
 			"	brc 4,0b\n"
-			: "=&r" (old_val), MEMOP_OUT (__hp(addr))
-			: "r" (val), MEMOP_IN (__hp(addr))
+			: "=&r" (old_val), MEMOP_OUT (__hp(8, addr))
+			: "r" (val), MEMOP_IN (__hp(8, addr))
 			: "memory", "cc");
 		return old_val;
 	}
@@ -123,8 +128,8 @@ unsigned long _uatomic_cmpxchg(void *addr, unsigned long old,
 
 		__asm__ __volatile__(
 			"	cs %0,%2," MEMOP_REF(%3) "\n"
-			: "+r" (old_val), MEMOP_OUT (__hp(addr))
-			: "r" (_new), MEMOP_IN (__hp(addr))
+			: "+r" (old_val), MEMOP_OUT (__hp(4, addr))
+			: "r" (_new), MEMOP_IN (__hp(4, addr))
 			: "memory", "cc");
 		return old_val;
 	}
@@ -133,8 +138,8 @@ unsigned long _uatomic_cmpxchg(void *addr, unsigned long old,
 	{
 		__asm__ __volatile__(
 			"	csg %0,%2," MEMOP_REF(%3) "\n"
-			: "+r" (old), MEMOP_OUT (__hp(addr))
-			: "r" (_new), MEMOP_IN (__hp(addr))
+			: "+r" (old), MEMOP_OUT (__hp(8, addr))
+			: "r" (_new), MEMOP_IN (__hp(8, addr))
 			: "memory", "cc");
 		return old;
 	}