[gcc r14-281] libgcc CRIS: Define TARGET_HAS_NO_HW_DIVIDE

[gcc r14-281] libgcc CRIS: Define TARGET_HAS_NO_HW_DIVIDE

[Hans-Peter Nilsson]

https://gcc.gnu.org/g:d7f0bc05949481048d2fd524ecb2d892f6a04294

commit r14-281-gd7f0bc05949481048d2fd524ecb2d892f6a04294
Author: Hans-Peter Nilsson <hp@axis.com>
Date:   Thu Apr 27 02:00:33 2023 +0200

    libgcc CRIS: Define TARGET_HAS_NO_HW_DIVIDE
    
    With this, execution time for e.g. __moddi3 go from 59 to 40 cycles in
    the "fast" case or from 290 to 200 cycles in the "slow" case (when the
    !TARGET_HAS_NO_HW_DIVIDE variant calls division and modulus functions
    for 32-bit SImode), as exposed by gcc.c-torture/execute/arith-rand-ll.c
    compiled for -march=v10.
    
    Unfortunately, it just puts a performance improvement "dent" of 0.07%
    in a arith-rand-ll.c-based performance test - where all loops are also
    reduced to 1/10.
    
    The size of every affected libgcc function is reduced to less than
    half and they are all now leaf functions.
    
            * config/cris/t-cris (HOST_LIBGCC2_CFLAGS): Add
            -DTARGET_HAS_NO_HW_DIVIDE.

Diff:
---
 libgcc/config/cris/t-cris | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/libgcc/config/cris/t-cris b/libgcc/config/cris/t-cris
index b582974a42e..e0020294be9 100644
--- a/libgcc/config/cris/t-cris
+++ b/libgcc/config/cris/t-cris
@@ -8,3 +8,6 @@ $(LIB2ADD): $(srcdir)/config/cris/arit.c
 	echo "#define L$$name" > tmp-$@ \
 	&& echo '#include "$<"' >> tmp-$@ \
 	&& mv -f tmp-$@ $@
+
+# Use an appropriate implementation when implementing DImode division.
+HOST_LIBGCC2_CFLAGS += -DTARGET_HAS_NO_HW_DIVIDE