| Message ID | 20230917014418.1703031-1-apinski@marvell.com |
|---|---|
| State | New |
| Headers | show |
| Series | MATCH: Avoid recusive zero_one_valued_p for conversions | expand |
On Sun, Sep 17, 2023 at 3:45 AM Andrew Pinski via Gcc-patches <gcc-patches@gcc.gnu.org> wrote: > > So when VN finds a name which has a nop conversion, it says > both names are equivalent to each other and the valuaization > function for one will return the other. This normally does not > cause any issues as there is no recusive matches. But after > r14-4038-gb975c0dc3be285, there was one added. So we would > do an infinite recusion on the match and never finish. > This fixes the issue (and adds a comment in match.pd) by > for converts just handle one level instead of being recusive > always. > > OK? Bootstrapped and tested on x86_64-linux-gnu with no regressions. OK. > Note the testcase was reduced from tree-ssa-loop-niter.cc and then > changed slightly into C rather than C++ but it still needs exceptions > turned on get the IR that VN would produce this equivalence relationship > going on. Also had to turn off early inline to force put to be inlined later. > > PR tree-optimization/111435 > > gcc/ChangeLog: > > * match.pd (zero_one_valued_p): Don't do recusion > on converts. > > gcc/testsuite/ChangeLog: > > * gcc.c-torture/compile/pr111435-1.c: New test. > --- > gcc/match.pd | 8 +++++++- > .../gcc.c-torture/compile/pr111435-1.c | 18 ++++++++++++++++++ > 2 files changed, 25 insertions(+), 1 deletion(-) > create mode 100644 gcc/testsuite/gcc.c-torture/compile/pr111435-1.c > > diff --git a/gcc/match.pd b/gcc/match.pd > index 97405e6a5c3..887665633d4 100644 > --- a/gcc/match.pd > +++ b/gcc/match.pd > @@ -2188,8 +2188,14 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT) > > /* A conversion from an zero_one_valued_p is still a [0,1]. > This is useful when the range of a variable is not known */ > +/* Note this matches can't be recusive because of the way VN handles > + nop conversions being equivalent and then recusive between them. */ > (match zero_one_valued_p > - (convert@0 zero_one_valued_p)) > + (convert@0 @1) > + (if (INTEGRAL_TYPE_P (TREE_TYPE (@1)) > + && (TYPE_UNSIGNED (TREE_TYPE (@1)) > + || TYPE_PRECISION (TREE_TYPE (@1)) > 1) > + && wi::leu_p (tree_nonzero_bits (@1), 1)))) > > /* Transform { 0 or 1 } * { 0 or 1 } into { 0 or 1 } & { 0 or 1 }. */ > (simplify > diff --git a/gcc/testsuite/gcc.c-torture/compile/pr111435-1.c b/gcc/testsuite/gcc.c-torture/compile/pr111435-1.c > new file mode 100644 > index 00000000000..afa84dd59dd > --- /dev/null > +++ b/gcc/testsuite/gcc.c-torture/compile/pr111435-1.c > @@ -0,0 +1,18 @@ > +/* { dg-options "-fexceptions -fno-early-inlining" } */ > +/* { dg-require-effective-target exceptions } */ > + > +void find_slot_with_hash(const int *); > + > +void put(const int *k, const int *) { > + find_slot_with_hash(k); > +} > +unsigned len(); > +int *address(); > +void h(int header, int **bounds) { > + if (!*bounds) > + return; > + unsigned t = *bounds ? len() : 0; > + int queue_index = t; > + address()[(unsigned)queue_index] = 0; > + put(&header, &queue_index); > +} > -- > 2.31.1 >
diff --git a/gcc/match.pd b/gcc/match.pd index 97405e6a5c3..887665633d4 100644 --- a/gcc/match.pd +++ b/gcc/match.pd @@ -2188,8 +2188,14 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT) /* A conversion from an zero_one_valued_p is still a [0,1]. This is useful when the range of a variable is not known */ +/* Note this matches can't be recusive because of the way VN handles + nop conversions being equivalent and then recusive between them. */ (match zero_one_valued_p - (convert@0 zero_one_valued_p)) + (convert@0 @1) + (if (INTEGRAL_TYPE_P (TREE_TYPE (@1)) + && (TYPE_UNSIGNED (TREE_TYPE (@1)) + || TYPE_PRECISION (TREE_TYPE (@1)) > 1) + && wi::leu_p (tree_nonzero_bits (@1), 1)))) /* Transform { 0 or 1 } * { 0 or 1 } into { 0 or 1 } & { 0 or 1 }. */ (simplify diff --git a/gcc/testsuite/gcc.c-torture/compile/pr111435-1.c b/gcc/testsuite/gcc.c-torture/compile/pr111435-1.c new file mode 100644 index 00000000000..afa84dd59dd --- /dev/null +++ b/gcc/testsuite/gcc.c-torture/compile/pr111435-1.c @@ -0,0 +1,18 @@ +/* { dg-options "-fexceptions -fno-early-inlining" } */ +/* { dg-require-effective-target exceptions } */ + +void find_slot_with_hash(const int *); + +void put(const int *k, const int *) { + find_slot_with_hash(k); +} +unsigned len(); +int *address(); +void h(int header, int **bounds) { + if (!*bounds) + return; + unsigned t = *bounds ? len() : 0; + int queue_index = t; + address()[(unsigned)queue_index] = 0; + put(&header, &queue_index); +}