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-rw-r--r--gcc/doc/extend.texi19
1 files changed, 19 insertions, 0 deletions
diff --git a/gcc/doc/extend.texi b/gcc/doc/extend.texi
index e06caf3..89c5b4e 100644
--- a/gcc/doc/extend.texi
+++ b/gcc/doc/extend.texi
@@ -24581,6 +24581,25 @@ void ignore_vec_dep (int *a, int k, int c, int m)
@}
@end smallexample
+@cindex pragma GCC novector
+@item #pragma GCC novector
+
+With this pragma, the programmer asserts that the following loop should be
+prevented from executing concurrently with SIMD (single instruction multiple
+data) instructions.
+
+For example, the compiler cannot vectorize the following loop with the pragma:
+
+@smallexample
+void foo (int n, int *a, int *b, int *c)
+@{
+ int i, j;
+#pragma GCC novector
+ for (i = 0; i < n; ++i)
+ a[i] = b[i] + c[i];
+@}
+@end smallexample
+
@cindex pragma GCC unroll @var{n}
@item #pragma GCC unroll @var{n}