https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92880
Bug ID: 92880
Summary: Documentation for Built-in Vector-Extensions should
mention C99 Fixed-width ints as base types
Product: gcc
Version: 9.2.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: web
Assignee: unassigned at gcc dot gnu.org
Reporter: arthur200126 at gmail dot com
Target Milestone: ---
The current version of gcc doc section 6.52 "Using Vector Instructions through
Built-in Functions" does not seem to mention the possibility of using C99
fixed-width stdint types like uint32_t.
Since a quick test seems to show that these types do in fact work, it would be
a good idea to mention it in the documentation. This should, in theory, allow
programmers to write truly platform-independent vectorized code.
A test case with some knobs to play with:
#include <stdint.h>
#define namevxsi(u, l) vec_i##u##x##l##_t
#define mkvxsi(u, l) \
typedef uint##u##_t namevxsi(u, l) __attribute__ ((vector_size (l * u /
8)))
mkvxsi(8, 16); /* vec_i8x16_t */
#define vectype namevxsi(8, 16)
vectype op(vectype a, vectype b)
{
a = 2 * b + 1;
return a;
}
(Hell, it even works with __uint128_t.)
