| Message ID | orcyv137pa.fsf@lxoliva.fsfla.org |
|---|---|
| State | New |
| Headers | show |
| Series | -finline-stringops: allow expansion into edges [PR113002] | expand |
On Wed, Dec 20, 2023 at 3:54 AM Alexandre Oliva <oliva@adacore.com> wrote: > > > Builtin expanders for memset and memcpy may involve conditionals and > loops, but their sequences may be end up emitted in edges. Alas, > commit_one_edge_insertion rejects sequences that end with a jump, a > requirement that makes sense for insertions after expand, but not so > much during expand. > > During expand, jumps may appear in the middle of the insert sequence > as much as in the end, and it's only after committing edge insertions > out of PHI nodes that we go through the entire function splitting > blocks where needed, so relax the assert in commit_one_edge_insertion > so that jumps are accepted during expand even at the end of the > sequence. > > Regstrapping on x86_64-linux-gnu, after testing the testcase with a > cross compiler to ppc64le-linux-gnu. Ok to install? OK. > > Builtin expanders for memset and memcpy may involve conditionals and > loops, but their sequences may be end up emitted in edges. Alas, > commit_one_edge_insertion rejects sequences that end with a jump, a > requirement that makes sense for insertions after expand, but not so > much during expand. > > During expand, jumps may appear in the middle of the insert sequence > as much as in the end, and it's only after committing edge insertions > out of PHI nodes that we go through the entire function splitting > blocks where needed, so relax the assert in commit_one_edge_insertion > so that jumps are accepted during expand even at the end of the > sequence. > > > for gcc/ChangeLog > > PR rtl-optimization/113002 > * cfgrtl.cc (commit_one_edge_insertion): Tolerate jumps in the > inserted sequence during expand. > > for gcc/testsuite/ChangeLog > > PR rtl-optimization/113002 > * gcc.dg/vect/pr113002.c: New. > --- > gcc/cfgrtl.cc | 8 +++++++- > gcc/testsuite/gcc.dg/vect/pr113002.c | 13 +++++++++++++ > 2 files changed, 20 insertions(+), 1 deletion(-) > create mode 100644 gcc/testsuite/gcc.dg/vect/pr113002.c > > diff --git a/gcc/cfgrtl.cc b/gcc/cfgrtl.cc > index 2a3f853eed59b..437eb3a86d5c2 100644 > --- a/gcc/cfgrtl.cc > +++ b/gcc/cfgrtl.cc > @@ -2092,7 +2092,13 @@ commit_one_edge_insertion (edge e) > delete_insn (before); > } > else > - gcc_assert (!JUMP_P (last)); > + /* Some builtin expanders, such as those for memset and memcpy, > + may generate loops and conditionals, and those may get emitted > + into edges. That's ok while expanding to rtl, basic block > + boundaries will be identified and split afterwards. ??? Need > + we check whether the destination labels of any inserted jumps > + are also part of the inserted sequence? */ > + gcc_assert (!JUMP_P (last) || currently_expanding_to_rtl); > } > > /* Update the CFG for all queued instructions. */ > diff --git a/gcc/testsuite/gcc.dg/vect/pr113002.c b/gcc/testsuite/gcc.dg/vect/pr113002.c > new file mode 100644 > index 0000000000000..186710f64b422 > --- /dev/null > +++ b/gcc/testsuite/gcc.dg/vect/pr113002.c > @@ -0,0 +1,13 @@ > +/* { dg-do compile } */ > +/* { dg-require-effective-target int128 } */ > +/* { dg-options "-finline-stringops -Os" } */ > + > +typedef __int128 v64u128 __attribute__((vector_size(64))); > +int c; > +v64u128 u; > +void foo() { > + if (c) > + u = (v64u128){0}; > + else > + u = (v64u128){1}; > +} > > -- > Alexandre Oliva, happy hacker https://FSFLA.org/blogs/lxo/ > Free Software Activist GNU Toolchain Engineer > More tolerance and less prejudice are key for inclusion and diversity > Excluding neuro-others for not behaving ""normal"" is *not* inclusive
diff --git a/gcc/cfgrtl.cc b/gcc/cfgrtl.cc index 2a3f853eed59b..437eb3a86d5c2 100644 --- a/gcc/cfgrtl.cc +++ b/gcc/cfgrtl.cc @@ -2092,7 +2092,13 @@ commit_one_edge_insertion (edge e) delete_insn (before); } else - gcc_assert (!JUMP_P (last)); + /* Some builtin expanders, such as those for memset and memcpy, + may generate loops and conditionals, and those may get emitted + into edges. That's ok while expanding to rtl, basic block + boundaries will be identified and split afterwards. ??? Need + we check whether the destination labels of any inserted jumps + are also part of the inserted sequence? */ + gcc_assert (!JUMP_P (last) || currently_expanding_to_rtl); } /* Update the CFG for all queued instructions. */ diff --git a/gcc/testsuite/gcc.dg/vect/pr113002.c b/gcc/testsuite/gcc.dg/vect/pr113002.c new file mode 100644 index 0000000000000..186710f64b422 --- /dev/null +++ b/gcc/testsuite/gcc.dg/vect/pr113002.c @@ -0,0 +1,13 @@ +/* { dg-do compile } */ +/* { dg-require-effective-target int128 } */ +/* { dg-options "-finline-stringops -Os" } */ + +typedef __int128 v64u128 __attribute__((vector_size(64))); +int c; +v64u128 u; +void foo() { + if (c) + u = (v64u128){0}; + else + u = (v64u128){1}; +}