Convert be sinked into a vec_cond if both sides fold. Unlike other unary operations, we need to check that we still can handle this vec_cond's first operand is the same as the new truth type.
I tried a few different versions of this patch: view_convert to the new truth_type but that does not work as we always support all vec_cond afterwards. using expand_vec_cond_expr_p; but that would allow too much. I also tried to see if view_convert can be handled here but we end up with: _3 = VEC_COND_EXPR <_2, { Nan(-1), Nan(-1), Nan(-1), Nan(-1) }, { 0.0, 0.0, 0.0, 0.0 }>; Which isel does not know how to handle as just being a view_convert from `vector(4) <signed-boolean:32>` to `vector(4) float` and causes a regression with `g++.target/i386/pr88152.C` Note, in the case of the SVE testcase, we will sink negate after the convert and be able to remove a few extra instructions in the end. Also with this change gcc.target/aarch64/sve/cond_unary_5.c will now pass. OK? Bootstrapped and tested on x86_64-linux-gnu and aarch64-linux-gnu. gcc/ChangeLog: PR tree-optimization/111006 PR tree-optimization/110986 * match.pd: (op(vec_cond(a,b,c))): Handle convert for op. gcc/testsuite/ChangeLog: PR tree-optimization/111006 * gcc.target/aarch64/sve/cond_convert_7.c: New test. --- gcc/match.pd | 9 ++++++++ .../gcc.target/aarch64/sve/cond_convert_7.c | 23 +++++++++++++++++++ 2 files changed, 32 insertions(+) create mode 100644 gcc/testsuite/gcc.target/aarch64/sve/cond_convert_7.c diff --git a/gcc/match.pd b/gcc/match.pd index acd2a964917..ca5ab6f289d 100644 --- a/gcc/match.pd +++ b/gcc/match.pd @@ -4704,6 +4704,15 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT) (op (vec_cond:s @0 @1 @2)) (vec_cond @0 (op! @1) (op! @2)))) +/* Sink unary conversions to branches, but only if we do fold both + and the target's truth type is the same as we already have. */ +(for op (convert) + (simplify + (op (vec_cond:s @0 @1 @2)) + (if (VECTOR_TYPE_P (type) + && types_match (TREE_TYPE (@0), truth_type_for (type))) + (vec_cond @0 (op! @1) (op! @2))))) + /* Sink binary operation to branches, but only if we can fold it. */ (for op (tcc_comparison plus minus mult bit_and bit_ior bit_xor lshift rshift rdiv trunc_div ceil_div floor_div round_div diff --git a/gcc/testsuite/gcc.target/aarch64/sve/cond_convert_7.c b/gcc/testsuite/gcc.target/aarch64/sve/cond_convert_7.c new file mode 100644 index 00000000000..4bb95b92195 --- /dev/null +++ b/gcc/testsuite/gcc.target/aarch64/sve/cond_convert_7.c @@ -0,0 +1,23 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -ftree-vectorize -moverride=sve_width=256 -fdump-tree-optimized" } */ + +/* This is a modified reduced version of cond_unary_5.c */ + +void __attribute__ ((noipa)) +f0 (unsigned short *__restrict r, + int *__restrict a, + int *__restrict pred) +{ + for (int i = 0; i < 1024; ++i) + { + int p = pred[i]?-1:0; + r[i] = p ; + } +} + +/* { dg-final { scan-assembler-times {\tmov\tz[0-9]+\.h, p[0-7]+/z, #-1} 1 } } */ +/* { dg-final { scan-assembler-not {\tmov\tz[0-9]+\.[hs], p[0-7]+/z, #1} } } */ + +/* { dg-final { scan-tree-dump-not "VIEW_CONVERT_EXPR " "optimized" } } */ +/* { dg-final { scan-tree-dump-not " = -" "optimized" } } */ +/* { dg-final { scan-tree-dump-not " = \\\(vector" "optimized" } } */ -- 2.31.1