| Message ID | 20240311025813.3805399-1-quic_apinski@quicinc.com |
|---|---|
| State | New |
| Headers | show |
| Series | [COMMITTED] Fold: Fix up merge_truthop_with_opposite_arm for NaNs [PR95351] | expand |
> -----Original Message----- > From: Andrew Pinski (QUIC) <quic_apinski@quicinc.com> > Sent: Sunday, March 10, 2024 7:58 PM > To: gcc-patches@gcc.gnu.org > Cc: Andrew Pinski (QUIC) <quic_apinski@quicinc.com> > Subject: [COMMITTED] Fold: Fix up merge_truthop_with_opposite_arm for > NaNs [PR95351] > > The problem here is that merge_truthop_with_opposite_arm would use the > type of the result of the comparison rather than the operands of the > comparison to figure out if we are honoring NaNs. > This fixes that oversight and now we get the correct results in this case. > > Committed as obvious after a bootstrap/test on x86_64-linux-gnu. Committed to the GCC 13 branch too. Thanks, Andrew > > PR middle-end/95351 > > gcc/ChangeLog: > > * fold-const.cc (merge_truthop_with_opposite_arm): Use > the type of the operands of the comparison and not the type > of the comparison. > > gcc/testsuite/ChangeLog: > > * gcc.dg/float_opposite_arm-1.c: New test. > > Signed-off-by: Andrew Pinski <quic_apinski@quicinc.com> > --- > gcc/fold-const.cc | 3 ++- > gcc/testsuite/gcc.dg/float_opposite_arm-1.c | 17 +++++++++++++++++ > 2 files changed, 19 insertions(+), 1 deletion(-) create mode 100644 > gcc/testsuite/gcc.dg/float_opposite_arm-1.c > > diff --git a/gcc/fold-const.cc b/gcc/fold-const.cc index > 43105d20be3..299c22bf391 100644 > --- a/gcc/fold-const.cc > +++ b/gcc/fold-const.cc > @@ -6420,7 +6420,6 @@ static tree > merge_truthop_with_opposite_arm (location_t loc, tree op, tree cmpop, > bool rhs_only) > { > - tree type = TREE_TYPE (cmpop); > enum tree_code code = TREE_CODE (cmpop); > enum tree_code truthop_code = TREE_CODE (op); > tree lhs = TREE_OPERAND (op, 0); > @@ -6436,6 +6435,8 @@ merge_truthop_with_opposite_arm (location_t > loc, tree op, tree cmpop, > if (TREE_CODE_CLASS (code) != tcc_comparison) > return NULL_TREE; > > + tree type = TREE_TYPE (TREE_OPERAND (cmpop, 0)); > + > if (rhs_code == truthop_code) > { > tree newrhs = merge_truthop_with_opposite_arm (loc, rhs, cmpop, > rhs_only); diff --git a/gcc/testsuite/gcc.dg/float_opposite_arm-1.c > b/gcc/testsuite/gcc.dg/float_opposite_arm-1.c > new file mode 100644 > index 00000000000..d2dbff35066 > --- /dev/null > +++ b/gcc/testsuite/gcc.dg/float_opposite_arm-1.c > @@ -0,0 +1,17 @@ > +/* { dg-do compile } */ > +/* { dg-options "-O1 -fdump-tree-original -fdump-tree-optimized" } */ > +/* { dg-add-options ieee } */ > +/* PR middle-end/95351 */ > + > +int Foo(double possiblyNAN, double b, double c) { > + return (possiblyNAN <= 2.0) || ((possiblyNAN > 2.0) && (b > c)); } > + > +/* Make sure we don't remove either >/<= */ > + > +/* { dg-final { scan-tree-dump "possiblyNAN > 2.0e.0" "original" } } */ > +/* { dg-final { scan-tree-dump "possiblyNAN_\[0-9\]+.D. > 2.0e.0" > +"optimized" } } */ > + > +/* { dg-final { scan-tree-dump "possiblyNAN <= 2.0e.0" "original" } } > +*/ > +/* { dg-final { scan-tree-dump "possiblyNAN_\[0-9\]+.D. <= 2.0e.0" > +"optimized" } } */ > -- > 2.43.0
diff --git a/gcc/fold-const.cc b/gcc/fold-const.cc index 43105d20be3..299c22bf391 100644 --- a/gcc/fold-const.cc +++ b/gcc/fold-const.cc @@ -6420,7 +6420,6 @@ static tree merge_truthop_with_opposite_arm (location_t loc, tree op, tree cmpop, bool rhs_only) { - tree type = TREE_TYPE (cmpop); enum tree_code code = TREE_CODE (cmpop); enum tree_code truthop_code = TREE_CODE (op); tree lhs = TREE_OPERAND (op, 0); @@ -6436,6 +6435,8 @@ merge_truthop_with_opposite_arm (location_t loc, tree op, tree cmpop, if (TREE_CODE_CLASS (code) != tcc_comparison) return NULL_TREE; + tree type = TREE_TYPE (TREE_OPERAND (cmpop, 0)); + if (rhs_code == truthop_code) { tree newrhs = merge_truthop_with_opposite_arm (loc, rhs, cmpop, rhs_only); diff --git a/gcc/testsuite/gcc.dg/float_opposite_arm-1.c b/gcc/testsuite/gcc.dg/float_opposite_arm-1.c new file mode 100644 index 00000000000..d2dbff35066 --- /dev/null +++ b/gcc/testsuite/gcc.dg/float_opposite_arm-1.c @@ -0,0 +1,17 @@ +/* { dg-do compile } */ +/* { dg-options "-O1 -fdump-tree-original -fdump-tree-optimized" } */ +/* { dg-add-options ieee } */ +/* PR middle-end/95351 */ + +int Foo(double possiblyNAN, double b, double c) +{ + return (possiblyNAN <= 2.0) || ((possiblyNAN > 2.0) && (b > c)); +} + +/* Make sure we don't remove either >/<= */ + +/* { dg-final { scan-tree-dump "possiblyNAN > 2.0e.0" "original" } } */ +/* { dg-final { scan-tree-dump "possiblyNAN_\[0-9\]+.D. > 2.0e.0" "optimized" } } */ + +/* { dg-final { scan-tree-dump "possiblyNAN <= 2.0e.0" "original" } } */ +/* { dg-final { scan-tree-dump "possiblyNAN_\[0-9\]+.D. <= 2.0e.0" "optimized" } } */
The problem here is that merge_truthop_with_opposite_arm would use the type of the result of the comparison rather than the operands of the comparison to figure out if we are honoring NaNs. This fixes that oversight and now we get the correct results in this case. Committed as obvious after a bootstrap/test on x86_64-linux-gnu. PR middle-end/95351 gcc/ChangeLog: * fold-const.cc (merge_truthop_with_opposite_arm): Use the type of the operands of the comparison and not the type of the comparison. gcc/testsuite/ChangeLog: * gcc.dg/float_opposite_arm-1.c: New test. Signed-off-by: Andrew Pinski <quic_apinski@quicinc.com> --- gcc/fold-const.cc | 3 ++- gcc/testsuite/gcc.dg/float_opposite_arm-1.c | 17 +++++++++++++++++ 2 files changed, 19 insertions(+), 1 deletion(-) create mode 100644 gcc/testsuite/gcc.dg/float_opposite_arm-1.c