[gcc r17-2700] AVR: Add __negdi2_r10 to libgcc.

https://gcc.gnu.org/g:07e78425476eb1054d7e0973d6ef39ba73b62821

commit r17-2700-g07e78425476eb1054d7e0973d6ef39ba73b62821
Author: Georg-Johann Lay <[email protected]>
Date:   Sat Jul 25 15:14:50 2026 +0200

    AVR: Add __negdi2_r10 to libgcc.
    
    This patch introduces __negdi2_r10 to lib1funcs.S and tidies
    some 64-bit negations.
    
    libgcc/
            * config/avr/t-avr (FUNCS_notiny): Add _negdi2_r10.
            * config/avr/lib1funcs.S (__negdi2_r10): New function.
            (__divdi3_moddi3): Use it.
            * config/avr/lib1funcs-fixed.S (__mulQ64_work): Use it.

Diff:
---
 libgcc/config/avr/lib1funcs-fixed.S | 36 ++----------------------------------
 libgcc/config/avr/lib1funcs.S       | 31 +++++++++++++++++--------------
 libgcc/config/avr/t-avr             |  2 +-
 3 files changed, 20 insertions(+), 49 deletions(-)

diff --git a/libgcc/config/avr/lib1funcs-fixed.S b/libgcc/config/avr/lib1funcs-fixed.S
index 37f8151480da..f1b61e12e976 100644
--- a/libgcc/config/avr/lib1funcs-fixed.S
+++ b/libgcc/config/avr/lib1funcs-fixed.S
@@ -1154,40 +1154,8 @@ DEFUN __mulQ64_work
     eor     __tmp_reg__, B7
     push    __tmp_reg__
 
-    ;; A = |A|
-    .call_if_neg  A7, __negdi2
-
-    ;; Stash away |A|
-    wmov    r26, A6
-#ifdef __AVR_HAVE_MUL__
-    wmov    r0, A4
-#else
-    push    A5
-    push    A4
-#endif
-    push    A3
-    push    A2
-    push    A1
-    push    A0
-
-    ;; A = |B|
-    mov8    A0, B0
-    .call_if_neg  A7, __negdi2
-
-    ;; Restore B = |A|
-    wmov    B6, r26
-    pop     B0
-    pop     B1
-    pop     B2
-    pop     B3
-#ifdef __AVR_HAVE_MUL__
-    wmov    B4, r0
-    ;; No need to clear zero_reg since it won't be used until the
-    ;; next MUL in __umulditi3_raw -> __umulsidi3 -> __umulhisi3.
-#else
-    pop     B4
-    pop     B5
-#endif
+    .call_if_neg  A7, __negdi2          ; A = |A|
+    .call_if_neg  B7, __negdi2_r10      ; B = |B|
 
     set    ; for signed
     XICALL ; __muluxx3.2
diff --git a/libgcc/config/avr/lib1funcs.S b/libgcc/config/avr/lib1funcs.S
index 150cf82336a6..f780a6965dc4 100644
--- a/libgcc/config/avr/lib1funcs.S
+++ b/libgcc/config/avr/lib1funcs.S
@@ -1816,26 +1816,15 @@ DEFUN  __divdi3_moddi3
 22: ldi     NN, 1 << 7
     eor     SS, NN
 
-    ldi NN, -1
-    com B4     $  com B5     $  com B6     $  com B7
-               $  com B1     $  com B2     $  com B3
-    NEG B0
-               $  sbc B1,NN  $  sbc B2,NN  $  sbc B3,NN
-    sbc B4,NN  $  sbc B5,NN  $  sbc B6,NN  $  sbc B7,NN
+    XCALL   __negdi2_r10
 
 3:  ;; Do the unsigned 64-Bit Division/Modulo (depending on T-flag)
     XCALL   __udivmod64
 
     ;; Adjust Result's Sign
-#ifdef __AVR_ERRATA_SKIP_JMP_CALL__
-    tst     SS
-    brpl    4f
-#else
-    sbrc    SS, 7
-#endif /* __AVR_HAVE_JMP_CALL__ */
-    XCALL   __negdi2
+    .call_if_neg  SS, __negdi2
 
-4:  ;; Epilogue: Restore 12 Registers and return
+    ;; Epilogue: Restore 12 Registers and return
     do_epilogue_restores 12
 
 ENDF __divdi3_moddi3
@@ -1931,6 +1920,20 @@ DEFUN __negdi2
 ENDF __negdi2
 #endif /* L_negdi2 */
 
+#if defined (L_negdi2_r10)
+;; (set (reg:DI 10)
+;;      (neg:DI (reg:DI 10)))
+;; Requires zero_reg R1 = 0.
+DEFUN __negdi2_r10
+    COM  B7         $ com  B6       $ com  B5       $ com  B4
+    com  B3         $ com  B2       $ com  B1       $ com  B0
+
+    ADC  B0, r1     $ adc  B1, r1   $ adc  B2, r1   $ adc  B3, r1
+    adc  B4, r1     $ adc  B5, r1   $ adc  B6, r1   $ adc  B7, r1
+    ret
+ENDF __negdi2_r10
+#endif /* L_negdi2_r10 */
+
 #undef TT
 
 #undef C7
diff --git a/libgcc/config/avr/t-avr b/libgcc/config/avr/t-avr
index df85485e0a79..657c61a56664 100644
--- a/libgcc/config/avr/t-avr
+++ b/libgcc/config/avr/t-avr
@@ -67,7 +67,7 @@ FUNCS_notiny = \
 	_mulsidi3 _umulsidi3 \
 	_divdi3 _udivdi3 \
 	_udivmod64 \
-	_negdi2 \
+	_negdi2 _negdi2_r10 \
 	_prologue \
 	_epilogue \
 	_load_3 _load_4 \