Committed as obvious.
The typo here, is obviously mistaken removal of lines next
to a line that was validly removed. Targets affected are
those with a delay-slot *and* defining TARGET_FLAGS_REGNUM.
In-tree, a git-grep says the only ones matching are CRIS,
h8300 and visium. The code removal has the effect of
wrong-code, not reverting the effect of r11-2814.
I'm "guessing" it was the effect of an incorrect conflict
resolution in preparatory work for the r12-440 /
bd1cd0d0e0fe / "Remove CC0" commit, when rebasing a related
branch, and not testing any of the affected targets. Either
way, the effect was a btest-gcc.sh state of "regress-1152"
for cris-elf. FWIW, I wrote the removed code (sans the
validly removed cc0 line), a part of what was committed at
2020-08-24 as 0e6c51de8ec47 / r11-2814.
This commit gets cris-elf test-results back to a sane state
(tested at 0ffdbc85d9a6 / r12-761).
gcc:
* reorg.c (fill_slots_from_thread): Reinstate code typoed out in
"Remove CC0".
---
gcc/reorg.c | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/gcc/reorg.c b/gcc/reorg.c
index 4595f9a541f0..7f06a6f6d092 100644
--- a/gcc/reorg.c
+++ b/gcc/reorg.c
@@ -2375,6 +2375,16 @@ fill_slots_from_thread (rtx_jump_insn *insn, rtx
condition,
if (! insn_references_resource_p (trial, &set, true)
&& ! insn_sets_resource_p (trial, filter_flags ? &fset : &set, true)
&& ! insn_sets_resource_p (trial, &needed, true)
+ /* If we're handling sets to the flags register specially, we
+ only allow an insn into a delay-slot, if it either:
+ - doesn't set the flags register,
+ - the "set" of the flags register isn't used (clobbered),
+ - insns between the delay-slot insn and the trial-insn
+ as accounted in "set", have not affected the flags register. */
+ && (! filter_flags
+ || ! insn_sets_resource_p (trial, &flags_res, true)
+ || find_regno_note (trial, REG_UNUSED, targetm.flags_regnum)
+ || ! TEST_HARD_REG_BIT (set.regs, targetm.flags_regnum))
&& ! can_throw_internal (trial))
{
rtx_insn *prior_insn;
--
2.11.0
brgds, H-P
