From e15425e899e4a9eec768cf74aaf36cdbf1d29913 Mon Sep 17 00:00:00 2001 From: Andrew MacLeod Date: Mon, 14 Feb 2022 19:43:40 -0500 Subject: [PATCH] Use GORI to evaluate arguments of a COND_EXPR. Provide an API into gori to perform a basic evaluation of the arguments of a COND_EXPR if they are in the dependency chain of the condition. PR tree-optimization/104526 gcc/ * gimple-range-fold.cc (fold_using_range::range_of_cond_expr): Call new routine. * gimple-range-gori.cc (range_def_chain::get_def_chain): Force a build of dependency chain if there isn't one. (gori_compute::condexpr_adjust): New. * gimple-range-gori.h (class gori_compute): New prototype. gcc/testsuite/ * gcc.dg/pr104526.c: New. --- gcc/gimple-range-fold.cc | 12 ++++++ gcc/gimple-range-gori.cc | 96 ++++++++++++++++++++++++++++++++++++++++- gcc/gimple-range-gori.h | 2 + gcc/testsuite/gcc.dg/pr104526.c | 15 +++++++ 4 files changed, 124 insertions(+), 1 deletion(-) create mode 100644 gcc/testsuite/gcc.dg/pr104526.c diff --git a/gcc/gimple-range-fold.cc b/gcc/gimple-range-fold.cc index 5133a43..2fc8376 100644 --- a/gcc/gimple-range-fold.cc +++ b/gcc/gimple-range-fold.cc @@ -1270,6 +1270,18 @@ fold_using_range::range_of_cond_expr (irange &r, gassign *s, fur_source &src) src.get_operand (range1, op1); src.get_operand (range2, op2); + // Try to see if there is a dependence between the COND and either operand + if (src.gori ()) + if (src.gori ()->condexpr_adjust (range1, range2, s, cond, op1, op2, src)) + if (dump_file && (dump_flags & TDF_DETAILS)) + { + fprintf (dump_file, "Possible COND_EXPR adjustment. Range op1 : "); + range1.dump(dump_file); + fprintf (dump_file, " and Range op2: "); + range2.dump(dump_file); + fprintf (dump_file, "\n"); + } + // If the condition is known, choose the appropriate expression. if (cond_range.singleton_p ()) { diff --git a/gcc/gimple-range-gori.cc b/gcc/gimple-range-gori.cc index 3e53283..258da6e 100644 --- a/gcc/gimple-range-gori.cc +++ b/gcc/gimple-range-gori.cc @@ -334,7 +334,7 @@ range_def_chain::get_def_chain (tree name) unsigned v = SSA_NAME_VERSION (name); // If it has already been processed, just return the cached value. - if (has_def_chain (name)) + if (has_def_chain (name) && m_def_chain[v].bm) return m_def_chain[v].bm; // No definition chain for default defs. @@ -1303,6 +1303,100 @@ gori_compute::outgoing_edge_range_p (irange &r, edge e, tree name, return false; } +// Given COND ? OP1 : OP2 with ranges R1 for OP1 and R2 for OP2, Use gori +// to further resolve R1 and R2 if there are any dependencies between +// OP1 and COND or OP2 and COND. All values can are to be calculated using SRC +// as the origination source location for operands.. +// Effectively, use COND an the edge condition and solve for OP1 on the true +// edge and OP2 on the false edge. + +bool +gori_compute::condexpr_adjust (irange &r1, irange &r2, gimple *, tree cond, + tree op1, tree op2, fur_source &src) +{ + int_range_max tmp, cond_true, cond_false; + tree ssa1 = gimple_range_ssa_p (op1); + tree ssa2 = gimple_range_ssa_p (op2); + if (!ssa1 && !ssa2) + return false; + if (!COMPARISON_CLASS_P (cond)) + return false; + tree type = TREE_TYPE (TREE_OPERAND (cond, 0)); + if (type != TREE_TYPE (TREE_OPERAND (cond, 1))) + return false; + range_operator *hand = range_op_handler (TREE_CODE (cond), type); + if (!hand) + return false; + + tree c1 = gimple_range_ssa_p (TREE_OPERAND (cond, 0)); + tree c2 = gimple_range_ssa_p (TREE_OPERAND (cond, 1)); + + // Only solve if there is one SSA name in the condition. + if ((!c1 && !c2) || (c1 && c2)) + return false; + + // Pick up the current values of each part of the condition. + int_range_max cl, cr; + src.get_operand (cl, TREE_OPERAND (cond, 0)); + src.get_operand (cr, TREE_OPERAND (cond, 1)); + + tree cond_name = c1 ? c1 : c2; + gimple *def_stmt = SSA_NAME_DEF_STMT (cond_name); + + // Evaluate the value of COND_NAME on the true and false edges, using either + // the op1 or op2 routines based on its location. + if (c1) + { + if (!hand->op1_range (cond_false, type, m_bool_zero, cr)) + return false; + if (!hand->op1_range (cond_true, type, m_bool_one, cr)) + return false; + cond_false.intersect (cl); + cond_true.intersect (cl); + } + else + { + if (!hand->op2_range (cond_false, type, m_bool_zero, cl)) + return false; + if (!hand->op2_range (cond_true, type, m_bool_one, cl)) + return false; + cond_false.intersect (cr); + cond_true.intersect (cr); + } + + unsigned idx; + if ((idx = tracer.header ("cond_expr evaluation : "))) + { + fprintf (dump_file, " range1 = "); + r1.dump (dump_file); + fprintf (dump_file, ", range2 = "); + r1.dump (dump_file); + fprintf (dump_file, "\n"); + } + + // Now solve for SSA1 or SSA2 if they are in the dependency chain. + if (ssa1 && in_chain_p (ssa1, cond_name)) + { + if (compute_operand_range (tmp, def_stmt, cond_true, ssa1, src)) + r1.intersect (tmp); + } + if (ssa2 && in_chain_p (ssa2, cond_name)) + { + if (compute_operand_range (tmp, def_stmt, cond_false, ssa2, src)) + r2.intersect (tmp); + } + if (idx) + { + tracer.print (idx, "outgoing: range1 = "); + r1.dump (dump_file); + fprintf (dump_file, ", range2 = "); + r1.dump (dump_file); + fprintf (dump_file, "\n"); + tracer.trailer (idx, "cond_expr", true, cond_name, cond_true); + } + return true; +} + // Dump what is known to GORI computes to listing file F. void diff --git a/gcc/gimple-range-gori.h b/gcc/gimple-range-gori.h index b799a84..605884e 100644 --- a/gcc/gimple-range-gori.h +++ b/gcc/gimple-range-gori.h @@ -158,6 +158,8 @@ class gori_compute : public gori_map public: gori_compute (int not_executable_flag = 0); bool outgoing_edge_range_p (irange &r, edge e, tree name, range_query &q); + bool condexpr_adjust (irange &r1, irange &r2, gimple *s, tree cond, tree op1, + tree op2, fur_source &src); bool has_edge_range_p (tree name, basic_block bb = NULL); bool has_edge_range_p (tree name, edge e); void dump (FILE *f); diff --git a/gcc/testsuite/gcc.dg/pr104526.c b/gcc/testsuite/gcc.dg/pr104526.c new file mode 100644 index 0000000..a295308 --- /dev/null +++ b/gcc/testsuite/gcc.dg/pr104526.c @@ -0,0 +1,15 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -fdump-tree-evrp" } */ + +void foo(void); + +static int a, b = 1, *c = &b; +int main() { + for (; a; a--) { + int d = 2 >> (1 / *c); + if (!d) + foo(); + } +} + +/* { dg-final { scan-tree-dump-not "foo" "evrp" } } */ -- 2.7.4