Hi,
Thanks for your insight and helpful review! "Kewen.Lin" <li...@linux.ibm.com> writes: > Hi Jeff, > > on 2023/12/6 13:24, Jiufu Guo wrote: >> Hi, >> >> For constant building e.g. r120=0x66666666, which does not fit 'li or lis', >> 'pli' is used to build this constant via 'emit_move_insn'. >> >> While for a complicated constant, e.g. 0x6666666666666666ULL, when using >> 'rs6000_emit_set_long_const' to split the constant recursively, it fails to >> use 'pli' to build the half part constant: 0x66666666. >> >> 'rs6000_emit_set_long_const' could be updated to use 'pli' to build half >> part of the constant when necessary. For example: 0x6666666666666666ULL, >> "pli 3,1717986918; rldimi 3,3,32,0" can be used. >> >> Compare with previous: >> https://gcc.gnu.org/pipermail/gcc-patches/2023-November/636567.html >> This verion is refreshed and added with a new testcase. >> >> Bootstrap®test pass on ppc64{,le}. >> Is this ok for trunk? >> >> BR, >> Jeff (Jiufu Guo) >> >> gcc/ChangeLog: >> >> * config/rs6000/rs6000.cc (rs6000_emit_set_long_const): Add code to use >> pli for 34bit constant. >> >> gcc/testsuite/ChangeLog: >> >> * gcc.target/powerpc/const_split_pli.c: New test. > > Nit: Now we have: > > gcc/testsuite/gcc.target/powerpc/const-build.c > gcc/testsuite/gcc.target/powerpc/const_anchors.c > gcc/testsuite/gcc.target/powerpc/const-compare.c > > I prefer the name of this new case is like const-build-1.c > (put a detailed comment inside) or const-build-split-pli.c, > to align with the existing. Thanks! > >> >> --- >> gcc/config/rs6000/rs6000.cc | 7 +++++++ >> gcc/testsuite/gcc.target/powerpc/const_split_pli.c | 9 +++++++++ >> 2 files changed, 16 insertions(+) >> create mode 100644 gcc/testsuite/gcc.target/powerpc/const_split_pli.c >> >> diff --git a/gcc/config/rs6000/rs6000.cc b/gcc/config/rs6000/rs6000.cc >> index dbdc72dce5d..2e074a21a05 100644 >> --- a/gcc/config/rs6000/rs6000.cc >> +++ b/gcc/config/rs6000/rs6000.cc >> @@ -10509,6 +10509,13 @@ rs6000_emit_set_long_const (rtx dest, HOST_WIDE_INT >> c, int *num_insns) >> GEN_INT (0xffffffff))); >> }; >> >> + if (TARGET_PREFIXED && SIGNED_INTEGER_34BIT_P (c)) >> + { >> + /* li/lis/pli */ >> + count_or_emit_insn (dest, GEN_INT (c)); >> + return; >> + } >> + >> if ((ud4 == 0xffff && ud3 == 0xffff && ud2 == 0xffff && (ud1 & 0x8000)) >> || (ud4 == 0 && ud3 == 0 && ud2 == 0 && !(ud1 & 0x8000))) >> { >> diff --git a/gcc/testsuite/gcc.target/powerpc/const_split_pli.c >> b/gcc/testsuite/gcc.target/powerpc/const_split_pli.c >> new file mode 100644 >> index 00000000000..626c93084aa >> --- /dev/null >> +++ b/gcc/testsuite/gcc.target/powerpc/const_split_pli.c >> @@ -0,0 +1,9 @@ >> +/* { dg-do compile { target lp64 } } */ >> +/* { dg-options "-O2" } */ > > It needs -mdejagnu-cpu=power10 as well. Yeap, thanks. > >> +/* { dg-require-effective-target power10_ok } */ >> + >> +unsigned long long msk66() { return 0x6666666666666666ULL; } >> + >> +/* { dg-final { scan-assembler-times {\mpli\M} 1 } } */ >> +/* { dg-final { scan-assembler-not {\mli\M} } } */ >> +/* { dg-final { scan-assembler-not {\mlis\M} } } */ > > OK for trunk with the above nits tweaked, thanks! > > BR, > Kewen
