+/*
+ * filter-visitor-generate-ir.c
+ *
+ * LTTng filter generate intermediate representation
+ *
+ * Copyright 2012 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ *
+ * This library is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License, version 2.1 only,
+ * as published by the Free Software Foundation.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this library; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <stdio.h>
+#include <unistd.h>
+#include <string.h>
+#include <stdlib.h>
+#include <assert.h>
+#include <errno.h>
+#include <inttypes.h>
+#include "filter-parser.h"
+#include "filter-ast.h"
+#include "filter-ir.h"
+
+static
+struct ir_op *generate_ir_recursive(struct filter_parser_ctx *ctx,
+ struct filter_node *node, enum ir_side side);
+
+static
+struct ir_op *make_op_root(struct ir_op *child, enum ir_side side)
+{
+ struct ir_op *op;
+
+ op = calloc(sizeof(struct ir_op), 1);
+ if (!op)
+ return NULL;
+ switch (child->data_type) {
+ case IR_DATA_UNKNOWN:
+ default:
+ fprintf(stderr, "[error] Unknown root child data type\n");
+ return NULL;
+ case IR_DATA_STRING:
+ fprintf(stderr, "[error] String cannot be root data type\n");
+ return NULL;
+ case IR_DATA_NUMERIC:
+ case IR_DATA_FIELD_REF:
+ /* ok */
+ break;
+ }
+ op->op = IR_OP_ROOT;
+ op->side = side;
+ op->data_type = child->data_type;
+ op->signedness = child->signedness;
+ op->u.root.child = child;
+ return op;
+}
+
+static
+struct ir_op *make_op_load_string(char *string, enum ir_side side)
+{
+ struct ir_op *op;
+
+ op = calloc(sizeof(struct ir_op), 1);
+ if (!op)
+ return NULL;
+ op->op = IR_OP_LOAD;
+ op->data_type = IR_DATA_STRING;
+ op->signedness = IR_SIGN_UNKNOWN;
+ op->side = side;
+ op->u.load.u.string = strdup(string);
+ if (!op->u.load.u.string) {
+ free(op);
+ return NULL;
+ }
+ return op;
+}
+
+static
+struct ir_op *make_op_load_numeric(int64_t v, enum ir_side side)
+{
+ struct ir_op *op;
+
+ op = calloc(sizeof(struct ir_op), 1);
+ if (!op)
+ return NULL;
+ op->op = IR_OP_LOAD;
+ op->data_type = IR_DATA_NUMERIC;
+ /* TODO: for now, all numeric values are signed */
+ op->signedness = IR_SIGNED;
+ op->side = side;
+ op->u.load.u.num = v;
+ return op;
+}
+
+static
+struct ir_op *make_op_load_field_ref(char *string, enum ir_side side)
+{
+ struct ir_op *op;
+
+ op = calloc(sizeof(struct ir_op), 1);
+ if (!op)
+ return NULL;
+ op->op = IR_OP_LOAD;
+ op->data_type = IR_DATA_FIELD_REF;
+ op->signedness = IR_SIGN_DYN;
+ op->side = side;
+ op->u.load.u.ref = strdup(string);
+ if (!op->u.load.u.ref) {
+ free(op);
+ return NULL;
+ }
+ return op;
+}
+
+static
+struct ir_op *make_op_unary(enum unary_op_type unary_op_type,
+ const char *op_str, enum ir_op_signedness signedness,
+ struct ir_op *child, enum ir_side side)
+{
+ struct ir_op *op = NULL;
+
+ if (child->data_type == IR_DATA_STRING) {
+ fprintf(stderr, "[error] unary operation '%s' not allowed on string literal\n", op_str);
+ goto error;
+ }
+
+ op = calloc(sizeof(struct ir_op), 1);
+ if (!op)
+ return NULL;
+ op->op = IR_OP_UNARY;
+ op->data_type = child->data_type;
+ op->signedness = signedness;
+ op->side = side;
+ op->u.unary.type = unary_op_type;
+ op->u.unary.child = child;
+ return op;
+
+error:
+ free(op);
+ return NULL;
+}
+
+/*
+ * unary + is pretty much useless.
+ */
+static
+struct ir_op *make_op_unary_plus(struct ir_op *child, enum ir_side side)
+{
+ return make_op_unary(AST_UNARY_PLUS, "+", child->signedness,
+ child, side);
+}
+
+static
+struct ir_op *make_op_unary_minus(struct ir_op *child, enum ir_side side)
+{
+ return make_op_unary(AST_UNARY_MINUS, "-", child->signedness,
+ child, side);
+}
+
+static
+struct ir_op *make_op_unary_not(struct ir_op *child, enum ir_side side)
+{
+ return make_op_unary(AST_UNARY_NOT, "!", child->signedness,
+ child, side);
+}
+
+#if 0
+static
+struct ir_op *make_op_binary_numeric(enum op_type bin_op_type,
+ const char *op_str, struct ir_op *left, struct ir_op *right,
+ enum ir_side side)
+{
+ struct ir_op *op = NULL;
+
+ if (right->data_type == IR_DATA_STRING
+ || right->data_type == IR_DATA_STRING) {
+ fprintf(stderr, "[error] binary operation '%s' not allowed on string literal\n", op_str);
+ goto error;
+ }
+ if (left->data_type == IR_DATA_UNKNOWN
+ || right->data_type == IR_DATA_UNKNOWN) {
+ fprintf(stderr, "[error] binary operation '%s' has unknown type for both children\n", op_str);
+ goto error;
+
+ }
+
+ op = calloc(sizeof(struct ir_op_binary), 1);
+ if (!op)
+ return NULL;
+ op->op = IR_OP_BINARY;
+ op->u.binary.type = bin_op_type;
+ op->u.binary.left = left;
+ op->u.binary.right = right;
+ op->side = side;
+
+ /*
+ * The field that is not a field ref will select type.
+ */
+ if (left->data_type != IR_DATA_FIELD_REF)
+ op->data_type = left->data_type;
+ else
+ op->data_type = right->data_type;
+
+ if (left->signedness == IR_SIGNED
+ || right->signedness == IR_SIGNED) {
+ op->signedness = IR_SIGNED;
+ } else if (left->signedness == IR_SIGN_DYN
+ || right->signedness == IR_SIGN_DYN) {
+ op->signedness = IR_SIGN_DYN;
+ } else if (left->signedness == IR_UNSIGNED
+ && right->signedness == IR_UNSIGNED) {
+ op->signedness = IR_UNSIGNED;
+ } else {
+ op->signedness = IR_SIGN_UNKNOWN;
+ }
+
+ return op;
+
+error:
+ free(op);
+ return NULL;
+}
+
+static
+struct ir_op *make_op_binary_mul(struct ir_op *left, struct ir_op *right,
+ enum ir_side side)
+{
+ return make_op_binary_numeric(AST_OP_MUL, "*", left, right, side);
+}
+
+static
+struct ir_op *make_op_binary_div(struct ir_op *left, struct ir_op *right,
+ enum ir_side side)
+{
+ return make_op_binary_numeric(AST_OP_DIV, "/", left, right, side);
+}
+
+static
+struct ir_op *make_op_binary_mod(struct ir_op *left, struct ir_op *right,
+ enum ir_side side)
+{
+ return make_op_binary_numeric(AST_OP_MOD, "%", left, right, side);
+}
+
+static
+struct ir_op *make_op_binary_plus(struct ir_op *left, struct ir_op *right,
+ enum ir_side side)
+{
+ return make_op_binary_numeric(AST_OP_PLUS, "+", left, right, side);
+}
+
+static
+struct ir_op *make_op_binary_minus(struct ir_op *left, struct ir_op *right,
+ enum ir_side side)
+{
+ return make_op_binary_numeric(AST_OP_MINUS, "-", left, right, side);
+}
+
+static
+struct ir_op *make_op_binary_rshift(struct ir_op *left, struct ir_op *right,
+ enum ir_side side)
+{
+ return make_op_binary_numeric(AST_OP_RSHIFT, ">>", left, right, side);
+}
+
+static
+struct ir_op *make_op_binary_lshift(struct ir_op *left, struct ir_op *right,
+ enum ir_side side)
+{
+ return make_op_binary_numeric(AST_OP_LSHIFT, "<<", left, right, side);
+}
+
+static
+struct ir_op *make_op_binary_and(struct ir_op *left, struct ir_op *right,
+ enum ir_side side)
+{
+ return make_op_binary_numeric(AST_OP_BIN_AND, "&", left, right, side);
+}
+
+static
+struct ir_op *make_op_binary_or(struct ir_op *left, struct ir_op *right,
+ enum ir_side side)
+{
+ return make_op_binary_numeric(AST_OP_BIN_OR, "|", left, right, side);
+}
+
+static
+struct ir_op *make_op_binary_xor(struct ir_op *left, struct ir_op *right,
+ enum ir_side side)
+{
+ return make_op_binary_numeric(AST_OP_BIN_XOR, "^", left, right, side);
+}
+#endif //0
+
+static
+struct ir_op *make_op_binary_compare(enum op_type bin_op_type,
+ const char *op_str, struct ir_op *left, struct ir_op *right,
+ enum ir_side side)
+{
+ struct ir_op *op = NULL;
+
+ if (left->data_type == IR_DATA_UNKNOWN
+ || right->data_type == IR_DATA_UNKNOWN) {
+ fprintf(stderr, "[error] binary operation '%s' has unknown operand type\n", op_str);
+ goto error;
+
+ }
+ if ((left->data_type == IR_DATA_STRING
+ && right->data_type == IR_DATA_NUMERIC)
+ || (left->data_type == IR_DATA_NUMERIC &&
+ right->data_type == IR_DATA_STRING)) {
+ fprintf(stderr, "[error] binary operation '%s' operand type mismatch\n", op_str);
+ goto error;
+ }
+
+ op = calloc(sizeof(struct ir_op), 1);
+ if (!op)
+ return NULL;
+ op->op = IR_OP_BINARY;
+ op->u.binary.type = bin_op_type;
+ op->u.binary.left = left;
+ op->u.binary.right = right;
+
+ /* we return a boolean, represented as signed numeric */
+ op->data_type = IR_DATA_NUMERIC;
+ op->signedness = IR_SIGNED;
+ op->side = side;
+
+ return op;
+
+error:
+ free(op);
+ return NULL;
+}
+
+static
+struct ir_op *make_op_binary_eq(struct ir_op *left, struct ir_op *right,
+ enum ir_side side)
+{
+ return make_op_binary_compare(AST_OP_EQ, "==", left, right, side);
+}
+
+static
+struct ir_op *make_op_binary_ne(struct ir_op *left, struct ir_op *right,
+ enum ir_side side)
+{
+ return make_op_binary_compare(AST_OP_NE, "!=", left, right, side);
+}
+
+static
+struct ir_op *make_op_binary_gt(struct ir_op *left, struct ir_op *right,
+ enum ir_side side)
+{
+ return make_op_binary_compare(AST_OP_GT, ">", left, right, side);
+}
+
+static
+struct ir_op *make_op_binary_lt(struct ir_op *left, struct ir_op *right,
+ enum ir_side side)
+{
+ return make_op_binary_compare(AST_OP_LT, "<", left, right, side);
+}
+
+static
+struct ir_op *make_op_binary_ge(struct ir_op *left, struct ir_op *right,
+ enum ir_side side)
+{
+ return make_op_binary_compare(AST_OP_GE, ">=", left, right, side);
+}
+
+static
+struct ir_op *make_op_binary_le(struct ir_op *left, struct ir_op *right,
+ enum ir_side side)
+{
+ return make_op_binary_compare(AST_OP_LE, "<=", left, right, side);
+}
+
+static
+struct ir_op *make_op_binary_logical(enum op_type bin_op_type,
+ const char *op_str, struct ir_op *left, struct ir_op *right,
+ enum ir_side side)
+{
+ struct ir_op *op = NULL;
+
+ if (left->data_type == IR_DATA_UNKNOWN
+ || right->data_type == IR_DATA_UNKNOWN) {
+ fprintf(stderr, "[error] binary operation '%s' has unknown operand type\n", op_str);
+ goto error;
+
+ }
+ if (left->data_type == IR_DATA_STRING
+ || right->data_type == IR_DATA_STRING) {
+ fprintf(stderr, "[error] logical binary operation '%s' cannot have string operand\n", op_str);
+ goto error;
+ }
+
+ op = calloc(sizeof(struct ir_op), 1);
+ if (!op)
+ return NULL;
+ op->op = IR_OP_LOGICAL;
+ op->u.binary.type = bin_op_type;
+ op->u.binary.left = left;
+ op->u.binary.right = right;
+
+ /* we return a boolean, represented as signed numeric */
+ op->data_type = IR_DATA_NUMERIC;
+ op->signedness = IR_SIGNED;
+ op->side = side;
+
+ return op;
+
+error:
+ free(op);
+ return NULL;
+}
+
+static
+struct ir_op *make_op_binary_logical_and(struct ir_op *left, struct ir_op *right,
+ enum ir_side side)
+{
+ return make_op_binary_logical(AST_OP_AND, "&&", left, right, side);
+}
+
+static
+struct ir_op *make_op_binary_logical_or(struct ir_op *left, struct ir_op *right,
+ enum ir_side side)
+{
+ return make_op_binary_logical(AST_OP_OR, "||", left, right, side);
+}
+
+static
+void filter_free_ir_recursive(struct ir_op *op)
+{
+ if (!op)
+ return;
+ switch (op->op) {
+ case IR_OP_UNKNOWN:
+ default:
+ fprintf(stderr, "[error] Unknown op type in %s\n",
+ __func__);
+ break;
+ case IR_OP_ROOT:
+ filter_free_ir_recursive(op->u.root.child);
+ break;
+ case IR_OP_LOAD:
+ switch (op->data_type) {
+ case IR_DATA_STRING:
+ free(op->u.load.u.string);
+ break;
+ case IR_DATA_FIELD_REF:
+ free(op->u.load.u.ref);
+ break;
+ default:
+ break;
+ }
+ break;
+ case IR_OP_UNARY:
+ filter_free_ir_recursive(op->u.unary.child);
+ break;
+ case IR_OP_BINARY:
+ filter_free_ir_recursive(op->u.binary.left);
+ filter_free_ir_recursive(op->u.binary.right);
+ break;
+ case IR_OP_LOGICAL:
+ filter_free_ir_recursive(op->u.logical.left);
+ filter_free_ir_recursive(op->u.logical.right);
+ break;
+ }
+ free(op);
+}
+
+static
+struct ir_op *make_expression(struct filter_parser_ctx *ctx,
+ struct filter_node *node, enum ir_side side)
+{
+ switch (node->u.expression.type) {
+ case AST_EXP_UNKNOWN:
+ default:
+ fprintf(stderr, "[error] %s: unknown expression type\n", __func__);
+ return NULL;
+
+ case AST_EXP_STRING:
+ return make_op_load_string(node->u.expression.u.string, side);
+ case AST_EXP_CONSTANT:
+ return make_op_load_numeric(node->u.expression.u.constant,
+ side);
+ case AST_EXP_IDENTIFIER:
+ if (node->u.expression.pre_op != AST_LINK_UNKNOWN) {
+ fprintf(stderr, "[error] %s: dotted and dereferenced identifiers not supported\n", __func__);
+ return NULL;
+ }
+ return make_op_load_field_ref(node->u.expression.u.identifier,
+ side);
+ case AST_EXP_NESTED:
+ return generate_ir_recursive(ctx, node->u.expression.u.child,
+ side);
+ }
+}
+
+static
+struct ir_op *make_op(struct filter_parser_ctx *ctx,
+ struct filter_node *node, enum ir_side side)
+{
+ struct ir_op *op = NULL, *lchild, *rchild;
+ const char *op_str = "?";
+
+ switch (node->u.op.type) {
+ case AST_OP_UNKNOWN:
+ default:
+ fprintf(stderr, "[error] %s: unknown binary op type\n", __func__);
+ return NULL;
+
+ /*
+ * Binary operators other than comparators and logical and/or
+ * are not supported. If we ever want to support those, we will
+ * need a stack for the general case rather than just 2
+ * registers (see bytecode).
+ */
+ case AST_OP_MUL:
+ op_str = "*";
+ goto error_not_supported;
+ case AST_OP_DIV:
+ op_str = "/";
+ goto error_not_supported;
+ case AST_OP_MOD:
+ op_str = "%";
+ goto error_not_supported;
+ case AST_OP_PLUS:
+ op_str = "+";
+ goto error_not_supported;
+ case AST_OP_MINUS:
+ op_str = "-";
+ goto error_not_supported;
+ case AST_OP_RSHIFT:
+ op_str = ">>";
+ goto error_not_supported;
+ case AST_OP_LSHIFT:
+ op_str = "<<";
+ goto error_not_supported;
+ case AST_OP_BIN_AND:
+ op_str = "&";
+ goto error_not_supported;
+ case AST_OP_BIN_OR:
+ op_str = "|";
+ goto error_not_supported;
+ case AST_OP_BIN_XOR:
+ op_str = "^";
+ goto error_not_supported;
+
+ case AST_OP_EQ:
+ case AST_OP_NE:
+ case AST_OP_GT:
+ case AST_OP_LT:
+ case AST_OP_GE:
+ case AST_OP_LE:
+ lchild = generate_ir_recursive(ctx, node->u.op.lchild, IR_LEFT);
+ if (!lchild)
+ return NULL;
+ rchild = generate_ir_recursive(ctx, node->u.op.rchild, IR_RIGHT);
+ if (!rchild) {
+ filter_free_ir_recursive(lchild);
+ return NULL;
+ }
+ break;
+
+ case AST_OP_AND:
+ case AST_OP_OR:
+ /*
+ * Both children considered as left, since we need to
+ * populate R0.
+ */
+ lchild = generate_ir_recursive(ctx, node->u.op.lchild, IR_LEFT);
+ if (!lchild)
+ return NULL;
+ rchild = generate_ir_recursive(ctx, node->u.op.rchild, IR_LEFT);
+ if (!rchild) {
+ filter_free_ir_recursive(lchild);
+ return NULL;
+ }
+ break;
+ }
+
+ switch (node->u.op.type) {
+ case AST_OP_AND:
+ op = make_op_binary_logical_and(lchild, rchild, side);
+ break;
+ case AST_OP_OR:
+ op = make_op_binary_logical_or(lchild, rchild, side);
+ break;
+ case AST_OP_EQ:
+ op = make_op_binary_eq(lchild, rchild, side);
+ break;
+ case AST_OP_NE:
+ op = make_op_binary_ne(lchild, rchild, side);
+ break;
+ case AST_OP_GT:
+ op = make_op_binary_gt(lchild, rchild, side);
+ break;
+ case AST_OP_LT:
+ op = make_op_binary_lt(lchild, rchild, side);
+ break;
+ case AST_OP_GE:
+ op = make_op_binary_ge(lchild, rchild, side);
+ break;
+ case AST_OP_LE:
+ op = make_op_binary_le(lchild, rchild, side);
+ break;
+ default:
+ break;
+ }
+
+ if (!op) {
+ filter_free_ir_recursive(rchild);
+ filter_free_ir_recursive(lchild);
+ }
+ return op;
+
+error_not_supported:
+ fprintf(stderr, "[error] %s: binary operation '%s' not supported\n",
+ __func__, op_str);
+ return NULL;
+}
+
+static
+struct ir_op *make_unary_op(struct filter_parser_ctx *ctx,
+ struct filter_node *node, enum ir_side side)
+{
+ switch (node->u.unary_op.type) {
+ case AST_UNARY_UNKNOWN:
+ default:
+ fprintf(stderr, "[error] %s: unknown unary op type\n", __func__);
+ return NULL;
+
+ case AST_UNARY_PLUS:
+ {
+ struct ir_op *op, *child;
+
+ child = generate_ir_recursive(ctx, node->u.unary_op.child,
+ side);
+ if (!child)
+ return NULL;
+ op = make_op_unary_plus(child, side);
+ if (!op) {
+ filter_free_ir_recursive(child);
+ return NULL;
+ }
+ return op;
+ }
+ case AST_UNARY_MINUS:
+ {
+ struct ir_op *op, *child;
+
+ child = generate_ir_recursive(ctx, node->u.unary_op.child,
+ side);
+ if (!child)
+ return NULL;
+ op = make_op_unary_minus(child, side);
+ if (!op) {
+ filter_free_ir_recursive(child);
+ return NULL;
+ }
+ return op;
+ }
+ case AST_UNARY_NOT:
+ {
+ struct ir_op *op, *child;
+
+ child = generate_ir_recursive(ctx, node->u.unary_op.child,
+ side);
+ if (!child)
+ return NULL;
+ op = make_op_unary_not(child, side);
+ if (!op) {
+ filter_free_ir_recursive(child);
+ return NULL;
+ }
+ return op;
+ }
+ }
+}
+
+static
+struct ir_op *generate_ir_recursive(struct filter_parser_ctx *ctx,
+ struct filter_node *node, enum ir_side side)
+{
+ switch (node->type) {
+ case NODE_UNKNOWN:
+ default:
+ fprintf(stderr, "[error] %s: unknown node type\n", __func__);
+ return NULL;
+
+ case NODE_ROOT:
+ {
+ struct ir_op *op, *child;
+
+ child = generate_ir_recursive(ctx, node->u.root.child,
+ side);
+ if (!child)
+ return NULL;
+ op = make_op_root(child, side);
+ if (!op) {
+ filter_free_ir_recursive(child);
+ return NULL;
+ }
+ return op;
+ }
+ case NODE_EXPRESSION:
+ return make_expression(ctx, node, side);
+ case NODE_OP:
+ return make_op(ctx, node, side);
+ case NODE_UNARY_OP:
+ return make_unary_op(ctx, node, side);
+ }
+ return 0;
+}
+
+
+void filter_ir_free(struct filter_parser_ctx *ctx)
+{
+ filter_free_ir_recursive(ctx->ir_root);
+ ctx->ir_root = NULL;
+}
+
+int filter_visitor_ir_generate(struct filter_parser_ctx *ctx)
+{
+ struct ir_op *op;
+
+ op = generate_ir_recursive(ctx, &ctx->ast->root, IR_LEFT);
+ if (!op) {
+ return -EINVAL;
+ }
+ ctx->ir_root = op;
+ return 0;
+}