In ./gcc/regclass.c:reg_scan_mark_refs()
there is this source code:
case SET:
/* Count a set of the destination if it is a register. */
for (dest = SET_DEST (x);
GET_CODE (dest) == SUBREG || GET_CODE (dest) == STRICT_LOW_PART
|| GET_CODE (dest) == ZERO_EXTEND;
dest = XEXP (dest, 0))
;
This code counts the number of times a REG is changed (eventually used in
combine, reload, regrenumber, ...)
IMHO, the ZERO_EXTEND is a typo and should be a ZERO_EXTRACT, because (set
(zero_extract (reg foo bar)) are RTX that are actually generated in some
define_insn/define_expand insv (provided HAVE_insv) if the source deals with
bitfields.
As this code can already be seen in GCC 3.3.*, I guess this is not very
critical. But it leads to problems in a non-standard target (tricore) that uses
the information in REG_N_SETS().
Greets,
Georg-Johann Lay
[EMAIL PROTECTED]
--
Summary: REG_N_SETS holds wrong value
Product: gcc
Version: unknown
Status: UNCONFIRMED
Severity: minor
Priority: P3
Component: rtl-optimization
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: georgjohann at web dot de
GCC build triplet: any
GCC host triplet: any
GCC target triplet: any
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32790
