On Sun, Apr 28, 2024 at 8:31 AM Andrew Pinski <quic_apin...@quicinc.com> wrote: > > This adds a few early outs to value_replacement that I noticed > while rewriting this to use match-and-simplify but could be committed > seperately. > * virtual operands won't change so return early for them > * special case `A ? B : B` as that is already just `B` > > Also moves the check for NE/EQ earlier as calculating empty_or_with_defined_p > is an IR walk for a BB and that might be big. > > Bootstrapped and tested on x86_64-linux-gnu with no regressions.
OK. > gcc/ChangeLog: > > * tree-ssa-phiopt.cc (value_replacement): Move check for > NE/EQ earlier. > > Signed-off-by: Andrew Pinski <quic_apin...@quicinc.com> > --- > gcc/tree-ssa-phiopt.cc | 22 +++++++++++++++------- > 1 file changed, 15 insertions(+), 7 deletions(-) > > diff --git a/gcc/tree-ssa-phiopt.cc b/gcc/tree-ssa-phiopt.cc > index f1e07502b02..a2bdcb5eae8 100644 > --- a/gcc/tree-ssa-phiopt.cc > +++ b/gcc/tree-ssa-phiopt.cc > @@ -1131,6 +1131,21 @@ value_replacement (basic_block cond_bb, basic_block > middle_bb, > enum tree_code code; > bool empty_or_with_defined_p = true; > > + /* Virtual operands don't need to be handled. */ > + if (virtual_operand_p (arg1)) > + return 0; > + > + /* Special case A ? B : B as this will always simplify to B. */ > + if (operand_equal_for_phi_arg_p (arg0, arg1)) > + return 0; > + > + gcond *cond = as_a <gcond *> (*gsi_last_bb (cond_bb)); > + code = gimple_cond_code (cond); > + > + /* This transformation is only valid for equality comparisons. */ > + if (code != NE_EXPR && code != EQ_EXPR) > + return 0; > + > /* If the type says honor signed zeros we cannot do this > optimization. */ > if (HONOR_SIGNED_ZEROS (arg1)) > @@ -1161,13 +1176,6 @@ value_replacement (basic_block cond_bb, basic_block > middle_bb, > empty_or_with_defined_p = false; > } > > - gcond *cond = as_a <gcond *> (*gsi_last_bb (cond_bb)); > - code = gimple_cond_code (cond); > - > - /* This transformation is only valid for equality comparisons. */ > - if (code != NE_EXPR && code != EQ_EXPR) > - return 0; > - > /* We need to know which is the true edge and which is the false > edge so that we know if have abs or negative abs. */ > extract_true_false_edges_from_block (cond_bb, &true_edge, &false_edge); > -- > 2.43.0 >
