Hello,I have been experimenting with generating VEC_COND_EXPR from the front-end, and these are just a couple things I noticed.
1) optabs.c requires that the first argument of vec_cond_expr be a comparison, but verify_gimple_assign_ternary only checks is_gimple_condexpr, like for COND_EXPR. In the long term, it seems better to also allow ssa_name and vector_cst (thus match the is_gimple_condexpr condition), but for now I just want to know early if I created an invalid vec_cond_expr.
2) a little refactoring of the code to find a suitable vector type for comparison results, and one more place where it should be used (no testcase yet because I don't know if that path can be taken without front-end changes first). I did wonder, for tree-ssa-forwprop, about using directly TREE_TYPE (cond) without truth_type_for.
Hmm, now I am wondering whether I should have waited until I had front-end vec_cond_expr support to submit everything at once...
2012-09-27 Marc Glisse <marc.gli...@inria.fr> * tree-cfg.c (verify_gimple_assign_ternary): Stricter check on first argument of VEC_COND_EXPR. * tree.c (truth_type_for): New function. * tree.h (truth_type_for): Declare. * gimple-fold.c (and_comparisons_1): Call it. (or_comparisons_1): Likewise. * tree-ssa-forwprop.c (forward_propagate_into_cond): Likewise. -- Marc Glisse
Index: gcc/tree-ssa-forwprop.c =================================================================== --- gcc/tree-ssa-forwprop.c (revision 191810) +++ gcc/tree-ssa-forwprop.c (working copy) @@ -549,21 +549,22 @@ static bool forward_propagate_into_cond (gimple_stmt_iterator *gsi_p) { gimple stmt = gsi_stmt (*gsi_p); tree tmp = NULL_TREE; tree cond = gimple_assign_rhs1 (stmt); bool swap = false; /* We can do tree combining on SSA_NAME and comparison expressions. */ if (COMPARISON_CLASS_P (cond)) tmp = forward_propagate_into_comparison_1 (stmt, TREE_CODE (cond), - boolean_type_node, + truth_type_for + (TREE_TYPE (cond)), TREE_OPERAND (cond, 0), TREE_OPERAND (cond, 1)); else if (TREE_CODE (cond) == SSA_NAME) { enum tree_code code; tree name = cond; gimple def_stmt = get_prop_source_stmt (name, true, NULL); if (!def_stmt || !can_propagate_from (def_stmt)) return 0; Index: gcc/tree-cfg.c =================================================================== --- gcc/tree-cfg.c (revision 191810) +++ gcc/tree-cfg.c (working copy) @@ -3758,22 +3758,24 @@ verify_gimple_assign_ternary (gimple stm tree rhs2_type = TREE_TYPE (rhs2); tree rhs3 = gimple_assign_rhs3 (stmt); tree rhs3_type = TREE_TYPE (rhs3); if (!is_gimple_reg (lhs)) { error ("non-register as LHS of ternary operation"); return true; } - if (((rhs_code == VEC_COND_EXPR || rhs_code == COND_EXPR) - ? !is_gimple_condexpr (rhs1) : !is_gimple_val (rhs1)) + if (((rhs_code == COND_EXPR) ? !is_gimple_condexpr (rhs1) + : (rhs_code == VEC_COND_EXPR) ? (!is_gimple_condexpr (rhs1) + || is_gimple_val (rhs1)) + : !is_gimple_val (rhs1)) || !is_gimple_val (rhs2) || !is_gimple_val (rhs3)) { error ("invalid operands in ternary operation"); return true; } /* First handle operations that involve different types. */ switch (rhs_code) { Index: gcc/gimple-fold.c =================================================================== --- gcc/gimple-fold.c (revision 191810) +++ gcc/gimple-fold.c (working copy) @@ -23,21 +23,20 @@ along with GCC; see the file COPYING3. #include "coretypes.h" #include "tm.h" #include "tree.h" #include "flags.h" #include "function.h" #include "dumpfile.h" #include "tree-flow.h" #include "tree-ssa-propagate.h" #include "target.h" #include "gimple-fold.h" -#include "langhooks.h" /* Return true when DECL can be referenced from current unit. FROM_DECL (if non-null) specify constructor of variable DECL was taken from. We can get declarations that are not possible to reference for various reasons: 1) When analyzing C++ virtual tables. C++ virtual tables do have known constructors even when they are keyed to other compilation unit. Those tables can contain pointers to methods and vars @@ -1686,29 +1685,21 @@ and_var_with_comparison_1 (gimple stmt, (OP1A CODE1 OP1B) and (OP2A CODE2 OP2B), respectively. If this can be done without constructing an intermediate value, return the resulting tree; otherwise NULL_TREE is returned. This function is deliberately asymmetric as it recurses on SSA_DEFs in the first comparison but not the second. */ static tree and_comparisons_1 (enum tree_code code1, tree op1a, tree op1b, enum tree_code code2, tree op2a, tree op2b) { - tree truth_type = boolean_type_node; - if (TREE_CODE (TREE_TYPE (op1a)) == VECTOR_TYPE) - { - tree vec_type = TREE_TYPE (op1a); - tree elem = lang_hooks.types.type_for_size - (GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (vec_type))), 0); - truth_type = build_opaque_vector_type (elem, - TYPE_VECTOR_SUBPARTS (vec_type)); - } + tree truth_type = truth_type_for (TREE_TYPE (op1a)); /* First check for ((x CODE1 y) AND (x CODE2 y)). */ if (operand_equal_p (op1a, op2a, 0) && operand_equal_p (op1b, op2b, 0)) { /* Result will be either NULL_TREE, or a combined comparison. */ tree t = combine_comparisons (UNKNOWN_LOCATION, TRUTH_ANDIF_EXPR, code1, code2, truth_type, op1a, op1b); if (t) @@ -2158,29 +2149,21 @@ or_var_with_comparison_1 (gimple stmt, (OP1A CODE1 OP1B) and (OP2A CODE2 OP2B), respectively. If this can be done without constructing an intermediate value, return the resulting tree; otherwise NULL_TREE is returned. This function is deliberately asymmetric as it recurses on SSA_DEFs in the first comparison but not the second. */ static tree or_comparisons_1 (enum tree_code code1, tree op1a, tree op1b, enum tree_code code2, tree op2a, tree op2b) { - tree truth_type = boolean_type_node; - if (TREE_CODE (TREE_TYPE (op1a)) == VECTOR_TYPE) - { - tree vec_type = TREE_TYPE (op1a); - tree elem = lang_hooks.types.type_for_size - (GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (vec_type))), 0); - truth_type = build_opaque_vector_type (elem, - TYPE_VECTOR_SUBPARTS (vec_type)); - } + tree truth_type = truth_type_for (TREE_TYPE (op1a)); /* First check for ((x CODE1 y) OR (x CODE2 y)). */ if (operand_equal_p (op1a, op2a, 0) && operand_equal_p (op1b, op2b, 0)) { /* Result will be either NULL_TREE, or a combined comparison. */ tree t = combine_comparisons (UNKNOWN_LOCATION, TRUTH_ORIF_EXPR, code1, code2, truth_type, op1a, op1b); if (t) Index: gcc/tree.c =================================================================== --- gcc/tree.c (revision 191810) +++ gcc/tree.c (working copy) @@ -10243,20 +10243,36 @@ unsigned_type_for (tree type) /* If TYPE is an integral or pointer type, return an integer type with the same precision which is signed, or itself if TYPE is already a signed integer type. */ tree signed_type_for (tree type) { return signed_or_unsigned_type_for (0, type); } +/* If TYPE is a vector type, return a signed integer vector type with the + same width and number of subparts. Otherwise return boolean_type_node. */ + +tree +truth_type_for (tree type) +{ + if (TREE_CODE (type) == VECTOR_TYPE) + { + tree elem = lang_hooks.types.type_for_size + (GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (type))), 0); + return build_opaque_vector_type (elem, TYPE_VECTOR_SUBPARTS (type)); + } + else + return boolean_type_node; +} + /* Returns the largest value obtainable by casting something in INNER type to OUTER type. */ tree upper_bound_in_type (tree outer, tree inner) { double_int high; unsigned int det = 0; unsigned oprec = TYPE_PRECISION (outer); unsigned iprec = TYPE_PRECISION (inner); Index: gcc/tree.h =================================================================== --- gcc/tree.h (revision 191810) +++ gcc/tree.h (working copy) @@ -4762,20 +4762,21 @@ extern tree build_call_valist (tree, tre extern tree build_call_array_loc (location_t, tree, tree, int, const tree *); extern tree build_call_vec (tree, tree, VEC(tree,gc) *); /* Construct various nodes representing data types. */ extern tree make_signed_type (int); extern tree make_unsigned_type (int); extern tree signed_or_unsigned_type_for (int, tree); extern tree signed_type_for (tree); extern tree unsigned_type_for (tree); +extern tree truth_type_for (tree); extern void initialize_sizetypes (void); extern void fixup_unsigned_type (tree); extern tree build_pointer_type_for_mode (tree, enum machine_mode, bool); extern tree build_pointer_type (tree); extern tree build_reference_type_for_mode (tree, enum machine_mode, bool); extern tree build_reference_type (tree); extern tree build_vector_type_for_mode (tree, enum machine_mode); extern tree build_vector_type (tree innertype, int nunits); extern tree build_opaque_vector_type (tree innertype, int nunits); extern tree build_type_no_quals (tree);