on 2024/5/10 17:29, HAO CHEN GUI wrote: > Hi, > This patch enables overlapped by-piece operations. On rs6000, default > move/set/clear ratio is 2. So the overlap is only enabled with compare > by-pieces. > > Compared to previous version, the change is to remove power8 > requirement from test case. > https://gcc.gnu.org/pipermail/gcc-patches/2024-May/651045.html > > Bootstrapped and tested on powerpc64-linux BE and LE with no > regressions. Is it OK for the trunk?
OKļ¼thanks! BR, Kewen > > Thanks > Gui Haochen > > ChangeLog > rs6000: Enable overlapped by-pieces operations > > This patch enables overlapped by-piece operations by defining > TARGET_OVERLAP_OP_BY_PIECES_P to true. On rs6000, default move/set/clear > ratio is 2. So the overlap is only enabled with compare by-pieces. > > gcc/ > * config/rs6000/rs6000.cc (TARGET_OVERLAP_OP_BY_PIECES_P): Define. > > gcc/testsuite/ > * gcc.target/powerpc/block-cmp-9.c: New. > > patch.diff > diff --git a/gcc/config/rs6000/rs6000.cc b/gcc/config/rs6000/rs6000.cc > index 117999613d8..e713a1e1d57 100644 > --- a/gcc/config/rs6000/rs6000.cc > +++ b/gcc/config/rs6000/rs6000.cc > @@ -1776,6 +1776,9 @@ static const scoped_attribute_specs *const > rs6000_attribute_table[] = > #undef TARGET_CONST_ANCHOR > #define TARGET_CONST_ANCHOR 0x8000 > > +#undef TARGET_OVERLAP_OP_BY_PIECES_P > +#define TARGET_OVERLAP_OP_BY_PIECES_P hook_bool_void_true > + > > > /* Processor table. */ > diff --git a/gcc/testsuite/gcc.target/powerpc/block-cmp-9.c > b/gcc/testsuite/gcc.target/powerpc/block-cmp-9.c > new file mode 100644 > index 00000000000..f16429c2ffb > --- /dev/null > +++ b/gcc/testsuite/gcc.target/powerpc/block-cmp-9.c > @@ -0,0 +1,11 @@ > +/* { dg-do compile } */ > +/* { dg-options "-O2" } */ > +/* { dg-final { scan-assembler-not {\ml[hb]z\M} } } */ > + > +/* Test if by-piece overlap compare is enabled and following case is > + implemented by two overlap word loads and compares. */ > + > +int foo (const char* s1, const char* s2) > +{ > + return __builtin_memcmp (s1, s2, 7) == 0; > +}