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| author | Steven Bosscher <stevenb@suse.de> | 2005-01-05 23:19:23 +0000 |
|---|---|---|
| committer | Steven Bosscher <steven@gcc.gnu.org> | 2005-01-05 23:19:23 +0000 |
| commit | 46d096a3c7a69f3a8c88c88a3dcaa6925d242513 (patch) | |
| tree | 8d81e917b2a1cc0618df0ec47f5dcced22b199dc /gcc/rtl.def | |
| parent | b95ec5c19194b9595a4209b3dc953cd7a713a484 (diff) | |
| download | gcc-46d096a3c7a69f3a8c88c88a3dcaa6925d242513.zip gcc-46d096a3c7a69f3a8c88c88a3dcaa6925d242513.tar.gz gcc-46d096a3c7a69f3a8c88c88a3dcaa6925d242513.tar.bz2 | |
combine.c (expand_compound_operation): Add comment that we fall through after case.
* combine.c (expand_compound_operation) <ZERO_EXTRACT>: Add
comment that we fall through after case.
(mark_used_regs_combine): Don't expect a SIGN_EXTRACT in a SET_DEST.
(distribute_links): Likewise.
* cse.c (cse_insn): Likewise.
* cselib.c (cselib_invalidate_mem): Likewise.
* df.c: Update comments at the top of the file.
(read_modify_subreg_p): Update comments here too.
(df_def_record_1): Don't expect a SIGN_EXTRACT in a SET_DEST.
* flow.c (mark_set_1): Likewise.
(mark_used_regs): Likewise.
* gcse.c (mems_conflict_for_gcse_p): Likewise.
(canon_list_insert): Likewise.
(mark_set): Likewise.
(try_replace_reg): Likewise.
(store_killed_in_insn): Likewise.
* loop.c (count_one_set): Likewise.
(basic_induction_var): Likewise.
* postreload-gcse.c (find_mem_conflicts): Likewise.
* postreload.c (reload_combine_note_store): Likewise.
(move2add_note_store): Likewise.
* reload.c (find_equiv_reg): Likewise.
(mark_referenced_resources): Likewise.
* rtlanal.c (set_noop_p): Likewise.
(note_stores): Likewise.
(note_uses): Likewise.
* sched-deps.c (sched_analyze_1): Likewise.
* sched-rgn.c (check_live_1): Likewise.
(update_live_1): Likewise.
* config/i860/i860.c: Likewise.
* rtl.dec (SIGN_EXTRACT): Document that this cannot appear as
an lvalue.
(ZERO_EXTRACT): Mention that this one can be an lvalue.
* doc/rtl.texi: Update documentation for bit-fields and SET.
From-SVN: r92974
Diffstat (limited to 'gcc/rtl.def')
| -rw-r--r-- | gcc/rtl.def | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/gcc/rtl.def b/gcc/rtl.def index c20f61b..7bee09b 100644 --- a/gcc/rtl.def +++ b/gcc/rtl.def @@ -587,10 +587,12 @@ DEF_RTL_EXPR(PARITY, "parity", "e", RTX_UNARY) If BITS_BIG_ENDIAN is defined, the first bit is the msb and operand 2 counts from the msb of the memory unit. Otherwise, the first bit is the lsb and operand 2 counts from - the lsb of the memory unit. */ + the lsb of the memory unit. + This kind of expression can not appear as an lvalue in RTL. */ DEF_RTL_EXPR(SIGN_EXTRACT, "sign_extract", "eee", RTX_BITFIELD_OPS) -/* Similar for unsigned bit-field. */ +/* Similar for unsigned bit-field. + But note! This kind of expression _can_ appear as an lvalue. */ DEF_RTL_EXPR(ZERO_EXTRACT, "zero_extract", "eee", RTX_BITFIELD_OPS) /* For RISC machines. These save memory when splitting insns. */ |