2007-01-22 Josh Stone <joshua.i.stone@intel.com>

runtime/
	* loc2c-runtime.h (kread, kwrite): Tweaks to work better with
	reading and writing pointer values.
testsuite/
	* systemtap.base/deref.stp: Rewrite test, and now also check the ability
	to read/write pointers.

1 files changed, 24 insertions, 20 deletions

diff --git a/runtime/loc2c-runtime.h b/runtime/loc2c-runtime.h
index 4617f697..ce6d04b7 100644
--- a/runtime/loc2c-runtime.h
+++ b/runtime/loc2c-runtime.h
@@ -468,27 +468,25 @@
 /* x86 can't do 8-byte put/get_user_asm, so we have to split it */
 
 #define kread(ptr)						\
-  ({ 								\
-    typeof(*(ptr)) _r; 						\
-    if (sizeof(*(ptr)) == 8) { 					\
-      union { u64 q; u32 l[2]; } _q; 				\
-      _q.l[0] = (u32) deref(4, &((u32 *)(ptr))[0]); 		\
-      _q.l[1] = (u32) deref(4, &((u32 *)(ptr))[1]); 		\
-      _r = (typeof(*(ptr))) _q.q; 				\
-    } else 							\
-      _r = (typeof(*(ptr))) deref(sizeof(*(ptr)), (ptr)); 	\
-    _r; 							\
+  ({								\
+    union { typeof(*(ptr)) v; u32 l[2]; } _kr;			\
+    if (sizeof(*(ptr)) == 8) {					\
+      _kr.l[0] = (u32) deref(4, &((u32 *)(ptr))[0]);		\
+      _kr.l[1] = (u32) deref(4, &((u32 *)(ptr))[1]);		\
+    } else							\
+      _kr.v = (typeof(*(ptr))) deref(sizeof(*(ptr)), (ptr));	\
+    _kr.v;							\
   })
 
-#define kwrite(ptr, value)						\
-  ({ 									\
-    if (sizeof(*(ptr)) == 8) { 						\
-      union { u64 q; u32 l[2]; } _q; 					\
-      _q.q = (u64)(typeof(*(ptr)))(value);				\
-      store_deref(4, &((u32 *)(ptr))[0], _q.l[0]);			\
-      store_deref(4, &((u32 *)(ptr))[1], _q.l[1]);			\
-    } else 								\
-      store_deref(sizeof(*(ptr)), (ptr), (typeof(*(ptr)))(value));	\
+#define kwrite(ptr, value)						     \
+  ({									     \
+    if (sizeof(*(ptr)) == 8) {						     \
+      union { typeof(*(ptr)) v; u32 l[2]; } _kw;			     \
+      _kw.v = (typeof(*(ptr)))(value);					     \
+      store_deref(4, &((u32 *)(ptr))[0], _kw.l[0]);			     \
+      store_deref(4, &((u32 *)(ptr))[1], _kw.l[1]);			     \
+    } else								     \
+      store_deref(sizeof(*(ptr)), (ptr), (long)(typeof(*(ptr)))(value));     \
   })
 
 #else
@@ -496,6 +494,12 @@
 #define kread(ptr) \
   ( (typeof(*(ptr))) deref(sizeof(*(ptr)), (ptr)) )
 #define kwrite(ptr, value) \
-  ( store_deref(sizeof(*(ptr)), (ptr), (typeof(*(ptr)))(value)) )
+  ( store_deref(sizeof(*(ptr)), (ptr), (long)(typeof(*(ptr)))(value)) )
 
 #endif
+
+#define CATCH_DEREF_FAULT()				\
+  if (0) {						\
+deref_fault:						\
+    CONTEXT->last_error = "pointer dereference fault";	\
+  }