On Wed, 2020-03-25 at 23:10 -0400, Hans-Peter Nilsson wrote:
> On Wed, 25 Mar 2020, Jeff Law via Gcc-patches wrote:
>
> The patch you sent, as well as what you committed as r10-7383,
> was just a ChangeLog entry.
>
> > Bootstrapped on sh4-linux-gnu and sh4eb-linux-gnu. Regression testing in
> > progress (won't finish for ~12 hours). No new test as it's covered by
> > vector-
> > compare-1 in the testsuite.
>
> ...so I guess you've noticed by the time you read this. :]
:-)
Here's the actual patch:
commit 48817fbd7616f086ac7bb1dd38b862f78762c9b8
Author: Jeff Law <l...@redhat.com>
Date: Wed Mar 25 14:33:08 2020 -0600
Fix vector-compare-1 regressions on sh4/sh4eb caused by pattern
clobbering T reg without expressing that in its RTL.
PR rtl-optimization/90275
* config/sh/sh.md (mov_neg_si_t): Clobber the T register in the
pattern.
diff --git a/gcc/config/sh/sh.md b/gcc/config/sh/sh.md
index 4a1797160cf..fc80278a395 100644
--- a/gcc/config/sh/sh.md
+++ b/gcc/config/sh/sh.md
@@ -8395,9 +8395,15 @@
;; Store (negated) T bit as all zeros or ones in a reg.
;; subc Rn,Rn ! Rn = Rn - Rn - T; T = T
;; not Rn,Rn ! Rn = 0 - Rn
+;;
+;; Note the call to sh_split_treg_set_expr may clobber
+;; the T reg. We must express this, even though it's
+;; not immediately obvious this pattern changes the
+;; T register.
(define_insn_and_split "mov_neg_si_t"
[(set (match_operand:SI 0 "arith_reg_dest" "=r")
- (neg:SI (match_operand 1 "treg_set_expr")))]
+ (neg:SI (match_operand 1 "treg_set_expr")))
+ (clobber (reg:SI T_REG))]
"TARGET_SH1"
{
gcc_assert (t_reg_operand (operands[1], VOIDmode));
