+Tue Mar 2 01:40:01 1999 Franz Sirl <Franz.Sirl-kernel@lauterbach.com>
+ Jeffrey A Law (law@cygnus.com)
+
+ * cse.c (fold_rtx): Update comments for (const (minus (label) (label)))
+ case.
+ (cse_insn): Avoid creating a bogus REG_EQUAL note for
+ (const (minus (label) (label)))
+ (record_jump_cond): Fix mismatched paren in comment.
+
Tue Mar 2 01:07:12 1999 Dan Nicolaescu <dann@godzilla.ics.uci.edu>
* final.c (end_final): There are 11 words in the "main header"
/* Indicate this is a constant. This isn't a
valid form of CONST, but it will only be used
to fold the next insns and then discarded, so
- it should be safe. */
+ it should be safe.
+
+ Note this expression must be explicitly discarded,
+ by cse_insn, else it may end up in a REG_EQUAL note
+ and "escape" to cause problems elsewhere. */
return gen_rtx_CONST (GET_MODE (new), new);
}
}
/* If OP0 and OP1 are known equal, and either is a paradoxical SUBREG,
we know that they are also equal in the smaller mode (this is also
true for all smaller modes whether or not there is a SUBREG, but
- is not worth testing for with no SUBREG. */
+ is not worth testing for with no SUBREG). */
/* Note that GET_MODE (op0) may not equal MODE. */
if (code == EQ && GET_CODE (op0) == SUBREG
equivalent constant, we want to add a REG_NOTE. We don't want
to write a REG_EQUAL note for a constant pseudo since verifying that
that pseudo hasn't been eliminated is a pain. Such a note also
- won't help anything. */
+ won't help anything.
+
+ Avoid a REG_EQUAL note for (CONST (MINUS (LABEL_REF) (LABEL_REF)))
+ which can be created for a reference to a compile time computable
+ entry in a jump table. */
+
if (n_sets == 1 && src_const && GET_CODE (dest) == REG
- && GET_CODE (src_const) != REG)
+ && GET_CODE (src_const) != REG
+ && ! (GET_CODE (src_const) == CONST
+ && GET_CODE (XEXP (src_const, 0)) == MINUS
+ && GET_CODE (XEXP (XEXP (src_const, 0), 0)) == LABEL_REF
+ && GET_CODE (XEXP (XEXP (src_const, 0), 1)) == LABEL_REF))
{
tem = find_reg_note (insn, REG_EQUAL, NULL_RTX);