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| author | Jeff Law <jlaw@ventanamicro.com> | 2023-08-11 15:52:57 -0600 |
|---|---|---|
| committer | Jeff Law <jlaw@ventanamicro.com> | 2023-08-11 15:54:12 -0600 |
| commit | db08a096e4b19b91a7ec64f31a45549bb1f077ff (patch) | |
| tree | 6b5f032ac19ff53cbf6aec0248a31f754b018dd6 | |
| parent | 5bfb5e772f6cf121563f08d27d2c652ea469bbfb (diff) | |
| download | gcc-db08a096e4b19b91a7ec64f31a45549bb1f077ff.zip gcc-db08a096e4b19b91a7ec64f31a45549bb1f077ff.tar.gz gcc-db08a096e4b19b91a7ec64f31a45549bb1f077ff.tar.bz2 | |
[committed] Fix subdi3 synthesis on rx port
Some of Andrew's recent match.pd changes triggered a regression in my tester
for the rx processor for c-torture/execute/pr66940.c which would be exposed
only during an LTO compilation.
Specifically the subdi3_internal pattern had the wrong idiom to detect a carry
from the high word into the low word. It had the wrong opcode and the operands
were reversed.
This resulted in combine doing a simplification that was valid according to the
presented RTL, but which ultimately got the wrong result.
I would often say this was a latent bug. But the testsuite shows
builtin-arith-overflow-14 and builtin-arith-overflow-p18 failures are fixed as
well. So it's been visible indefinitely, but nobody's ever looked into those
failures.
Committed to the trunk.
gcc/
* config/rx/rx.md (subdi3): Fix test for borrow.
| -rw-r--r-- | gcc/config/rx/rx.md | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/gcc/config/rx/rx.md b/gcc/config/rx/rx.md index 6959c60..f6b13b9 100644 --- a/gcc/config/rx/rx.md +++ b/gcc/config/rx/rx.md @@ -1722,7 +1722,7 @@ (minus:SI (match_operand:SI 4 "register_operand" " 1, 1") (match_operand:SI 5 "rx_compare_operand" " rQ,rQ")) - (geu:SI (match_dup 2) (match_dup 3)))) + (gtu:SI (match_dup 3) (match_dup 2)))) (clobber (reg:CC CC_REG))] "" "#" |