[Bug tree-optimization/111015] [11/12/13/14 Regression] __int128 bitfields optimized incorrectly to the 64 bit operations

[mikpelinux at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111015

--- Comment #4 from Mikael Pettersson <mikpelinux at gmail dot com> ---
Reverting the pass_store_merging::process_store hunk makes this test case work
again:

diff --git a/gcc/gimple-ssa-store-merging.cc b/gcc/gimple-ssa-store-merging.cc
index 0d19b98ed73..c4bf8eec64e 100644
--- a/gcc/gimple-ssa-store-merging.cc
+++ b/gcc/gimple-ssa-store-merging.cc
@@ -5299,7 +5299,7 @@ pass_store_merging::process_store (gimple *stmt)
          && bitsize.is_constant (&const_bitsize)
          && ((const_bitsize % BITS_PER_UNIT) != 0
              || !multiple_p (bitpos, BITS_PER_UNIT))
-         && const_bitsize <= MAX_FIXED_MODE_SIZE)
+         && const_bitsize <= 64)
        {
          /* Bypass a conversion to the bit-field type.  */
          if (!bit_not_p