Originally the SVE port used the names for 256-bit vectors, as the
next available increment after Advanced SIMD. However, that was
always a bit of a hack and is bound to confuse people new to the code.
Nothing actually requires vector modes to have names of the form
V<nunits><mode>, and after talking it over with the AArch64 maintainers,
we agreed to switch to things like:
VNx16QI
instead. This patch lets targets pick this kind of prefix.
Tested on aarch64-linux-gnu (with and without SVE), x86_64-linux-gnu an
powerpc64le-linux-gnu. I'll apply this under the gen* maintainership
when the SVE port itself has been approved.
Thanks,
Richard
2017-11-17 Richard Sandiford <richard.sandif...@linaro.org>
gcc/
* machmode.def (VECTOR_MODES_WITH_PREFIX): Document.
* genmodes.c (VECTOR_MODES_WITH_PREFIX): New macro.
(VECTOR_MODES): Use it.
(make_vector_modes): Take the prefix as an argument.
Index: gcc/machmode.def
===================================================================
--- gcc/machmode.def 2017-11-17 21:46:15.177979825 +0000
+++ gcc/machmode.def 2017-11-17 21:46:25.555622937 +0000
@@ -142,6 +142,10 @@ along with GCC; see the file COPYING3.
than two bytes (if CLASS is FLOAT). CLASS must be INT or
FLOAT. The names follow the same rule as VECTOR_MODE uses.
+ VECTOR_MODES_WITH_PREFIX (PREFIX, CLASS, WIDTH);
+ Like VECTOR_MODES, but start the mode names with PREFIX instead
+ of the usual "V".
+
VECTOR_BOOL_MODE (NAME, COUNT, BYTESIZE)
Create a vector mode called NAME that contains COUNT boolean
elements and occupies BYTESIZE bytes in total. Each boolean
Index: gcc/genmodes.c
===================================================================
--- gcc/genmodes.c 2017-11-17 21:46:15.177050178 +0000
+++ gcc/genmodes.c 2017-11-17 21:46:25.554693290 +0000
@@ -483,9 +483,11 @@ make_complex_modes (enum mode_class cl,
/* For all modes in class CL, construct vector modes of width
WIDTH, having as many components as necessary. */
-#define VECTOR_MODES(C, W) make_vector_modes (MODE_##C, W, __FILE__, __LINE__)
+#define VECTOR_MODES_WITH_PREFIX(PREFIX, C, W) \
+ make_vector_modes (MODE_##C, #PREFIX, W, __FILE__, __LINE__)
+#define VECTOR_MODES(C, W) VECTOR_MODES_WITH_PREFIX (V, C, W)
static void ATTRIBUTE_UNUSED
-make_vector_modes (enum mode_class cl, unsigned int width,
+make_vector_modes (enum mode_class cl, const char *prefix, unsigned int width,
const char *file, unsigned int line)
{
struct mode_data *m;
@@ -516,8 +518,8 @@ make_vector_modes (enum mode_class cl, u
if (cl == MODE_INT && m->precision == 1)
continue;
- if ((size_t)snprintf (buf, sizeof buf, "V%u%s", ncomponents, m->name)
- >= sizeof buf)
+ if ((size_t) snprintf (buf, sizeof buf, "%s%u%s", prefix,
+ ncomponents, m->name) >= sizeof buf)
{
error ("%s:%d: mode name \"%s\" is too long",
m->file, m->line, m->name);
