[SPARC] Fix PR target/105292

[Eric Botcazou via Gcc-patches]

This is a regression present since the 10.x series, but the underlying issue 
has been there since the TARGET_VEC_PERM_CONST hook was implemented, in the 
form of an ICE when expanding a constant VEC_PERM_EXPR in V4QI, while the 
back-end only supports V8QI constant VEC_PERM_EXPRs.

Tested on SPARC/Solaris, applied to all active branches.


2022-05-10  Eric Botcazou  <ebotca...@adacore.com>

        PR target/105292
        * config/sparc/sparc.cc (sparc_vectorize_vec_perm_const): Return
        true only for 8-byte vector modes.


2022-05-10  Eric Botcazou  <ebotca...@adacore.com>

        * gcc.target/sparc/20220510-1.c: New test.

-- 
Eric Botcazou
diff --git a/gcc/config/sparc/sparc.cc b/gcc/config/sparc/sparc.cc
index 467a9f171d2..aca925befe1 100644
--- a/gcc/config/sparc/sparc.cc
+++ b/gcc/config/sparc/sparc.cc
@@ -13041,9 +13041,9 @@ sparc_vectorize_vec_perm_const (machine_mode vmode, rtx target, rtx op0,
   if (!TARGET_VIS2)
     return false;
 
-  /* All permutes are supported.  */
+  /* All 8-byte permutes are supported.  */
   if (!target)
-    return true;
+    return GET_MODE_SIZE (vmode) == 8;
 
   /* Force target-independent code to convert constant permutations on other
      modes down to V8QI.  Rely on this to avoid the complexity of the byte

/* PR target/105292 */
/* Reported by Koakuma <koachan+gccb...@protonmail.com> */

/* { dg-do compile } */
/* { dg-options "-O3 -mvis2" } */

extern void get_vbytes_v2 (unsigned);

typedef struct {
  unsigned ctt_info;
  unsigned ctt_size;
} ctf_type_t;

typedef struct {
  unsigned short cts_offset;
  unsigned short cts_bits;
} ctf_slice_t;

void flip_types_len (ctf_type_t *t, int bsx1, int bsx2)
{
  const int kind = t->ctt_info;

  get_vbytes_v2 (t->ctt_size);

  if (kind == 4)
    {
      ctf_slice_t *s = (ctf_slice_t *)t;
      s->cts_offset = __builtin_bswap16(bsx1);
      s->cts_bits   = __builtin_bswap16(bsx2);
    }
}