From 963d6142cc5339d919bccf902a53a507ba7cc3d6 Mon Sep 17 00:00:00 2001 From: Richard Kenner Date: Wed, 23 Jun 1993 07:54:14 -0400 Subject: [PATCH] (fill_slots_from_thread): When replacing a use of a register with what it was set to... (fill_slots_from_thread): When replacing a use of a register with what it was set to, don't do it when either the destination or source of the copy is set in the insn. From-SVN: r4716 --- gcc/reorg.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/gcc/reorg.c b/gcc/reorg.c index 3b6b20585d3..5b89943a24b 100644 --- a/gcc/reorg.c +++ b/gcc/reorg.c @@ -3237,9 +3237,11 @@ fill_slots_from_thread (insn, condition, thread, opposite_thread, likely, but it doesn't seem worth it. It might also be a good idea to try to swap the two insns. That might do better. - We can't do this if the next insn modifies our source, because that - would make the replacement into the insn invalid. This also - prevents updating the contents of a PRE_INC. */ + We can't do this if the next insn modifies our destination, because + that would make the replacement into the insn invalid. We also can't + do this if it modifies our source, because it might be an earlyclobber + operand. This latter test also prevents updating the contents of + a PRE_INC. */ if (GET_CODE (trial) == INSN && GET_CODE (pat) == SET && GET_CODE (SET_SRC (pat)) == REG @@ -3250,6 +3252,7 @@ fill_slots_from_thread (insn, condition, thread, opposite_thread, likely, if (next && GET_CODE (next) == INSN && GET_CODE (PATTERN (next)) != USE && ! reg_set_p (SET_DEST (pat), next) + && ! reg_set_p (SET_SRC (pat), next) && reg_referenced_p (SET_DEST (pat), PATTERN (next))) validate_replace_rtx (SET_DEST (pat), SET_SRC (pat), next); } -- 2.30.2