Hi Peter,
On 11/08/2018 12:35 PM, Peter Bergner wrote:
On 11/8/18 4:57 AM, Renlin Li wrote:
I think I found the problem!
As described in the PR, a hard register is used in
an pre/post modify expression. The hard register is live, but updated.
In this case, we should make it conflicting with all pseudos live at
that point. Does it make sense?
Do you have a reproducer test case I can look at? I'd like to see the
problematical rtl to help me determine whether your patch is correct
or not. ...and thank you for debugging this!
Peter
Sure! (I was trying to send the mail, but it failed with large attachment.)
I attached the dump file in the bugzilla ticket:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87899
I remove the unrelated dump (tar -xzvf xxx.tgz)
The code you want to check is the following in ira pass:
insn 10905: r1 = r2040
insn 208: use and update r1 with pre_modify
insn 191: use pseudo r2040
I could not create a test case. This dump is created with stage1 compiler
compiling next stage compiler.
The (not helpful) command line is:
/home/renlin/try-new/./prev-gcc/cc1plus -quiet -nostdinc++ -v -I
/home/renlin/try-new/prev-arm-none-linux-gnueabihf/libstdc++-v3/include/arm-none-linux-gnueabihf -I
/home/renlin/try-new/prev-arm-none-linux-gnueabihf/libstdc++-v3/include -I /home/renlin/gcc/libstdc++-v3/libsupc++ -I . -I . -I ../../gcc/gcc -I
../../gcc/gcc/. -I ../../gcc/gcc/../include -I ../../gcc/gcc/../libcpp/include -I ../../gcc/gcc/../libdecnumber -I ../../gcc/gcc/../libdecnumber/dpd
-I ../libdecnumber -I ../../gcc/gcc/../libbacktrace -imultilib . -imultiarch arm-linux-gnueabihf -iprefix
/home/renlin/try-new/prev-gcc/../lib/gcc/arm-none-linux-gnueabihf/9.0.0/ -isystem /home/renlin/try-new/./prev-gcc/include -isystem
/home/renlin/try-new/./prev-gcc/include-fixed -MMD tree-loop-distribution.d -MF ./.deps/tree-loop-distribution.TPo -MP -MT tree-loop-distribution.o
-D_GNU_SOURCE -D IN_GCC -D HAVE_CONFIG_H ../../gcc/gcc/tree-loop-distribution.c -quiet -dumpbase tree-loop-distribution.c -mfloat-abi=hard -mfpu=neon
-mthumb -mtls-dialect=gnu -march=armv7-a+simd -auxbase-strip tree-loop-distribution.s -g -gtoggle -O2 -Wextra -Wall -Wno-narrowing -Wwrite-strings
-Wcast-qual -Wsuggest-attribute=format -Woverloaded-virtual -Wpedantic -Wno-long-long -Wno-variadic-macros -Wno-overlength-strings -Werror -version
-fno-PIE -fno-checking -fno-exceptions -fno-rtti -fasynchronous-unwind-tables -fno-common -o tree-loop-distribution.s
Regards,
Renlin
