Clarify NON_SIMD_CALL instructions.
git-svn-id: svn://svn.valgrind.org/valgrind/trunk@6362 a5019735-40e9-0310-863c-91ae7b9d1cf9
diff --git a/include/valgrind.h b/include/valgrind.h
index dafc0d9..9cc0af9 100644
--- a/include/valgrind.h
+++ b/include/valgrind.h
@@ -3652,7 +3652,19 @@
/* These requests allow control to move from the simulated CPU to the
- real CPU, calling an arbitary function */
+ real CPU, calling an arbitary function.
+
+ Note that the current ThreadId is inserted as the first argument.
+ So this call:
+
+ VALGRIND_NON_SIMD_CALL2(f, arg1, arg2)
+
+ requires f to have this signature:
+
+ Word f(Word tid, Word arg1, Word arg2)
+
+ where "Word" is a word-sized type.
+*/
#define VALGRIND_NON_SIMD_CALL0(_qyy_fn) \
__extension__ \
({unsigned long _qyy_res; \