For pointers I forgot that BIT_IOR_EXPR is not valid so when I added the pattern to convert `max<a,b> != 0` (r15-5356), GCC would start to ICEing saying pointer types were not valid for BIT_IOR_EXPR. This fixes the problem by casting to the unsigned type of the inner type. There was another way of fixing this to handling it as `a == 0 & b == 0` but both match and reassoication (for pointers) will then convert it back into the form I am creating here so let's just use that form instead.
Bootstrapped and tested on x86_64-linux-gnu. PR tree-optimization/117646 gcc/ChangeLog: * match.pd (`max<a,b>==0`): Add casts to `unsigned type`. gcc/testsuite/ChangeLog: * gcc.dg/torture/minmaxneeqptr-1.c: New test. Signed-off-by: Andrew Pinski <quic_apin...@quicinc.com> --- gcc/match.pd | 6 ++++-- .../gcc.dg/torture/minmaxneeqptr-1.c | 21 +++++++++++++++++++ 2 files changed, 25 insertions(+), 2 deletions(-) create mode 100644 gcc/testsuite/gcc.dg/torture/minmaxneeqptr-1.c diff --git a/gcc/match.pd b/gcc/match.pd index 4bec24a21b2..f5181325f3b 100644 --- a/gcc/match.pd +++ b/gcc/match.pd @@ -4799,9 +4799,11 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT) MAX (A, B) != 0 -> (A|B) != 0 iff unsigned. */ (for cmp (eq ne) (simplify - (cmp (max @0 @1) integer_zerop@2) + (cmp (max @0 @1) integer_zerop) (if (TYPE_UNSIGNED (TREE_TYPE (@0))) - (cmp (bit_ior @0 @1) @2)))) + (with { tree utype = unsigned_type_for (TREE_TYPE (@0)); } + (cmp (bit_ior (convert:utype @0) (convert:utype @1)) + { build_zero_cst (utype); } ))))) /* Undo fancy ways of writing max/min or other ?: expressions, like a - ((a - b) & -(a < b)) and a - (a - b) * (a < b) into (a < b) ? b : a. diff --git a/gcc/testsuite/gcc.dg/torture/minmaxneeqptr-1.c b/gcc/testsuite/gcc.dg/torture/minmaxneeqptr-1.c new file mode 100644 index 00000000000..aa45722330f --- /dev/null +++ b/gcc/testsuite/gcc.dg/torture/minmaxneeqptr-1.c @@ -0,0 +1,21 @@ +/* { dg-do compile } */ + +/* PR tree-optimization/117646 */ + +int maxeq(char *a, char *b) { + char *p = a < b ? b : a; + return p == (void*)0; +} +int maxne(char *a, char *b) { + char *p = a < b ? b : a; + return p == (void*)0; +} + +int mineq(char *a, char *b) { + char *p = a > b ? b : a; + return p == (void*)0; +} +int minne(char *a, char *b) { + char *p = a > b ? b : a; + return p == (void*)0; +} -- 2.43.0