Update copyright years.

[thirdparty/gcc.git] / gcc / config / aarch64 / aarch64.c

diff --git a/gcc/config/aarch64/aarch64.c b/gcc/config/aarch64/aarch64.c
index 88baf96efc2d60d7dc4ea6e57900e51821902e6f..85cadef1be819b3c1ad68ae70e755e0150ad6469 100644 (file)
--- a/gcc/config/aarch64/aarch64.c
+++ b/gcc/config/aarch64/aarch64.c
@@ -1,5 +1,5 @@
 /* Machine description for AArch64 architecture.
-   Copyright (C) 2009-2019 Free Software Foundation, Inc.
+   Copyright (C) 2009-2020 Free Software Foundation, Inc.
    Contributed by ARM Ltd.
 
    This file is part of GCC.
@@ -16826,12 +16826,28 @@ aarch64_simd_valid_immediate (rtx op, simd_immediate_info *info,
        }
     }
 
-  unsigned int elt_size = GET_MODE_SIZE (elt_mode);
+  /* If all elements in an SVE vector have the same value, we have a free
+     choice between using the element mode and using the container mode.
+     Using the element mode means that unused parts of the vector are
+     duplicates of the used elements, while using the container mode means
+     that the unused parts are an extension of the used elements.  Using the
+     element mode is better for (say) VNx4HI 0x101, since 0x01010101 is valid
+     for its container mode VNx4SI while 0x00000101 isn't.
+
+     If not all elements in an SVE vector have the same value, we need the
+     transition from one element to the next to occur at container boundaries.
+     E.g. a fixed-length VNx4HI containing { 1, 2, 3, 4 } should be treated
+     in the same way as a VNx4SI containing { 1, 2, 3, 4 }.  */
+  scalar_int_mode elt_int_mode;
+  if ((vec_flags & VEC_SVE_DATA) && n_elts > 1)
+    elt_int_mode = aarch64_sve_container_int_mode (mode);
+  else
+    elt_int_mode = int_mode_for_mode (elt_mode).require ();
+
+  unsigned int elt_size = GET_MODE_SIZE (elt_int_mode);
   if (elt_size > 8)
     return false;
 
-  scalar_int_mode elt_int_mode = int_mode_for_mode (elt_mode).require ();
-
   /* Expand the vector constant out into a byte vector, with the least
      significant byte of the register first.  */
   auto_vec<unsigned char, 16> bytes;