procyberian/gcc
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

tree-optimization/107617 - big-endian .LEN_STORE VN

Browse source 
The following fixes a mistake in interpreting .LEN_STORE definitions
during value-numbering when in big-endian mode.  We cannot offset
the encoding of the RHS but instead encode to an offsetted position
which is then treated correctly by the endian aware copying code.

	PR tree-optimization/107617
	* tree-ssa-sccvn.cc (vn_walk_cb_data::push_partial_def):
	Handle negative pd.rhs_off.
	(vn_reference_lookup_3): Properly provide pd.rhs_off
	for .LEN_STORE on big-endian targets.
This commit is contained in:
Richard Biener 2022-11-28 12:38:46 +01:00
parent 512098a331
commit d3fee43fb3
1 changed files with 23 additions and 2 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

25
gcc/tree-ssa-sccvn.cc
View file

@ -2090,7 +2090,7 @@ vn_walk_cb_data::push_partial_def (pd_data pd,
len = ROUND_UP (pd.size, BITS_PER_UNIT) / BITS_PER_UNIT;
memset (this_buffer, 0, len);
}
else
else if (pd.rhs_off >= 0)
{
len = native_encode_expr (pd.rhs, this_buffer, bufsize,
(MAX (0, -pd.offset)
@ -2105,6 +2105,24 @@ vn_walk_cb_data::push_partial_def (pd_data pd,
return (void *)-1;
}
}
else /* negative pd.rhs_off indicates we want to chop off first bits */
{
if (-pd.rhs_off >= bufsize)
return (void *)-1;
len = native_encode_expr (pd.rhs,
this_buffer + -pd.rhs_off / BITS_PER_UNIT,
bufsize - -pd.rhs_off / BITS_PER_UNIT,
MAX (0, -pd.offset) / BITS_PER_UNIT);
if (len <= 0
|| len < (ROUND_UP (pd.size, BITS_PER_UNIT) / BITS_PER_UNIT
- MAX (0, -pd.offset) / BITS_PER_UNIT))
{
if (dump_file && (dump_flags & TDF_DETAILS))
fprintf (dump_file, "Failed to encode %u "
"partial definitions\n", ndefs);
return (void *)-1;
}
}
unsigned char *p = buffer;
HOST_WIDE_INT size = pd.size;
@ -3349,10 +3367,13 @@ vn_reference_lookup_3 (ao_ref *ref, tree vuse, void *data_,
}
else if (fn == IFN_LEN_STORE)
{
pd.rhs_off = 0;
pd.offset = offset2i;
pd.size = (tree_to_uhwi (len)
+ -tree_to_shwi (bias)) * BITS_PER_UNIT;
if (BYTES_BIG_ENDIAN)
pd.rhs_off = pd.size - tree_to_uhwi (TYPE_SIZE (vectype));
else
pd.rhs_off = 0;
if (ranges_known_overlap_p (offset, maxsize,
pd.offset, pd.size))
return data->push_partial_def (pd, set, set,