[lttng-tools.git] / src / lib / lttng-ctl / filter / filter-visitor-generate-bytecode.c

/*
 * filter-visitor-generate-bytecode.c
 *
 * LTTng filter bytecode generation
 *
 * 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 <stdlib.h>
#include <string.h>
#include <errno.h>
#include "align.h"
#include "filter-bytecode.h"
#include "filter-ir.h"
#include "filter-ast.h"

#ifndef max_t
#define max_t(type, a, b)	((type) ((a) > (b) ? (a) : (b)))
#endif

//#define INIT_ALLOC_SIZE		PAGE_SIZE
#define INIT_ALLOC_SIZE		4

static
int recursive_visit_gen_bytecode(struct filter_parser_ctx *ctx,
		struct ir_op *node);

static inline int fls(unsigned int x)
{
	int r = 32;

	if (!x)
		return 0;
	if (!(x & 0xFFFF0000U)) {
		x <<= 16;
		r -= 16;
	}
	if (!(x & 0xFF000000U)) {
		x <<= 8;
		r -= 8;
	}
	if (!(x & 0xF0000000U)) {
		x <<= 4;
		r -= 4;
	}
	if (!(x & 0xC0000000U)) {
		x <<= 2;
		r -= 2;
	}
	if (!(x & 0x80000000U)) {
		x <<= 1;
		r -= 1;
	}
	return r;
}

static inline int get_count_order(unsigned int count)
{
	int order;

	order = fls(count) - 1;
	if (count & (count - 1))
		order++;
	return order;
}

static
int bytecode_init(struct lttng_filter_bytecode_alloc **fb)
{
	uint32_t alloc_len;

	alloc_len = sizeof(struct lttng_filter_bytecode_alloc) + INIT_ALLOC_SIZE;
	*fb = calloc(alloc_len, 1);
	if (!*fb) {
		return -ENOMEM;
	} else {
		(*fb)->alloc_len = alloc_len;
		return 0;
	}
}

static
int32_t bytecode_reserve(struct lttng_filter_bytecode_alloc **fb, uint32_t align, uint32_t len)
{
	int32_t ret;
	uint32_t padding = offset_align((*fb)->b.len, align);
	uint32_t new_len = (*fb)->b.len + padding + len;
	uint32_t new_alloc_len = sizeof(struct lttng_filter_bytecode_alloc) + new_len;
	uint32_t old_alloc_len = (*fb)->alloc_len;

	if (new_len > LTTNG_FILTER_MAX_LEN)
		return -EINVAL;

	if (new_alloc_len > old_alloc_len) {
		new_alloc_len =
			max_t(uint32_t, 1U << get_count_order(new_alloc_len), old_alloc_len << 1);
		*fb = realloc(*fb, new_alloc_len);
		if (!*fb)
			return -ENOMEM;
		/* We zero directly the memory from start of allocation. */
		memset(&((char *) *fb)[old_alloc_len], 0, new_alloc_len - old_alloc_len);
		(*fb)->alloc_len = new_alloc_len;
	}
	(*fb)->b.len += padding;
	ret = (*fb)->b.len;
	(*fb)->b.len += len;
	return ret;
}

static
int bytecode_push(struct lttng_filter_bytecode_alloc **fb, const void *data,
		uint32_t align, uint32_t len)
{
	int32_t offset;

	offset = bytecode_reserve(fb, align, len);
	if (offset < 0)
		return offset;
	memcpy(&(*fb)->b.data[offset], data, len);
	return 0;
}

static
int bytecode_push_logical(struct lttng_filter_bytecode_alloc **fb,
		struct logical_op *data,
		uint32_t align, uint32_t len,
		uint16_t *skip_offset)
{
	int32_t offset;

	offset = bytecode_reserve(fb, align, len);
	if (offset < 0)
		return offset;
	memcpy(&(*fb)->b.data[offset], data, len);
	*skip_offset =
		(void *) &((struct logical_op *) &(*fb)->b.data[offset])->skip_offset
			- (void *) &(*fb)->b.data[0];
	return 0;
}

static
int bytecode_patch(struct lttng_filter_bytecode_alloc **fb,
		const void *data,
		uint16_t offset,
		uint32_t len)
{
	if (offset >= (*fb)->b.len) {
		return -EINVAL;
	}
	memcpy(&(*fb)->b.data[offset], data, len);
	return 0;
}

static
int visit_node_root(struct filter_parser_ctx *ctx, struct ir_op *node)
{
	int ret;
	struct return_op insn;

	/* Visit child */
	ret = recursive_visit_gen_bytecode(ctx, node->u.root.child);
	if (ret)
		return ret;

	/* Generate end of bytecode instruction */
	insn.op = FILTER_OP_RETURN;
	return bytecode_push(&ctx->bytecode, &insn, 1, sizeof(insn));
}

static
int visit_node_load(struct filter_parser_ctx *ctx, struct ir_op *node)
{
	int ret;

	switch (node->data_type) {
	case IR_DATA_UNKNOWN:
	default:
		fprintf(stderr, "[error] Unknown data type in %s\n",
			__func__);
		return -EINVAL;

	case IR_DATA_STRING:
	{
		struct load_op *insn;
		uint32_t insn_len = sizeof(struct load_op)
			+ strlen(node->u.load.u.string) + 1;

		insn = calloc(insn_len, 1);
		if (!insn)
			return -ENOMEM;
		insn->op = FILTER_OP_LOAD_STRING;
		strcpy(insn->data, node->u.load.u.string);
		ret = bytecode_push(&ctx->bytecode, insn, 1, insn_len);
		free(insn);
		return ret;
	}
	case IR_DATA_NUMERIC:
	{
		struct load_op *insn;
		uint32_t insn_len = sizeof(struct load_op)
			+ sizeof(struct literal_numeric);

		insn = calloc(insn_len, 1);
		if (!insn)
			return -ENOMEM;
		insn->op = FILTER_OP_LOAD_S64;
		*(int64_t *) insn->data = node->u.load.u.num;
		ret = bytecode_push(&ctx->bytecode, insn, 1, insn_len);
		free(insn);
		return ret;
	}
	case IR_DATA_FLOAT:
	{
		struct load_op *insn;
		uint32_t insn_len = sizeof(struct load_op)
			+ sizeof(struct literal_double);

		insn = calloc(insn_len, 1);
		if (!insn)
			return -ENOMEM;
		insn->op = FILTER_OP_LOAD_DOUBLE;
		*(double *) insn->data = node->u.load.u.flt;
		ret = bytecode_push(&ctx->bytecode, insn, 1, insn_len);
		free(insn);
		return ret;
	}
	case IR_DATA_FIELD_REF:
	{
		struct load_op *insn;
		uint32_t insn_len = sizeof(struct load_op)
			+ sizeof(struct field_ref);
		struct field_ref ref_offset;
		uint32_t reloc_offset_u32;
		uint16_t reloc_offset;

		insn = calloc(insn_len, 1);
		if (!insn)
			return -ENOMEM;
		insn->op = FILTER_OP_LOAD_FIELD_REF;
		ref_offset.offset = (uint16_t) -1U;
		memcpy(insn->data, &ref_offset, sizeof(ref_offset));
		/* reloc_offset points to struct load_op */
		reloc_offset_u32 = bytecode_get_len(&ctx->bytecode->b);
		if (reloc_offset_u32 > LTTNG_FILTER_MAX_LEN - 1) {
			free(insn);
			return -EINVAL;
		}
		reloc_offset = (uint16_t) reloc_offset_u32;
		ret = bytecode_push(&ctx->bytecode, insn, 1, insn_len);
		if (ret) {
			free(insn);
			return ret;
		}
		/* append reloc */
		ret = bytecode_push(&ctx->bytecode_reloc, &reloc_offset,
					1, sizeof(reloc_offset));
		if (ret) {
			free(insn);
			return ret;
		}
		ret = bytecode_push(&ctx->bytecode_reloc, node->u.load.u.ref,
					1, strlen(node->u.load.u.ref) + 1);
		free(insn);
		return ret;
	}
	}
}

static
int visit_node_unary(struct filter_parser_ctx *ctx, struct ir_op *node)
{
	int ret;
	struct unary_op insn;

	/* Visit child */
	ret = recursive_visit_gen_bytecode(ctx, node->u.unary.child);
	if (ret)
		return ret;

	/* Generate end of bytecode instruction */
	switch (node->u.unary.type) {
	case AST_UNARY_UNKNOWN:
	default:
		fprintf(stderr, "[error] Unknown unary node type in %s\n",
			__func__);
		return -EINVAL;
	case AST_UNARY_PLUS:
		/* Nothing to do. */
		return 0;
	case AST_UNARY_MINUS:
		insn.op = FILTER_OP_UNARY_MINUS;
		return bytecode_push(&ctx->bytecode, &insn, 1, sizeof(insn));
	case AST_UNARY_NOT:
		insn.op = FILTER_OP_UNARY_NOT;
		return bytecode_push(&ctx->bytecode, &insn, 1, sizeof(insn));
	}
}

/*
 * Binary comparator nesting is disallowed. This allows fitting into
 * only 2 registers.
 */
static
int visit_node_binary(struct filter_parser_ctx *ctx, struct ir_op *node)
{
	int ret;
	struct binary_op insn;

	/* Visit child */
	ret = recursive_visit_gen_bytecode(ctx, node->u.binary.left);
	if (ret)
		return ret;
	ret = recursive_visit_gen_bytecode(ctx, node->u.binary.right);
	if (ret)
		return ret;

	switch (node->u.binary.type) {
	case AST_OP_UNKNOWN:
	default:
		fprintf(stderr, "[error] Unknown unary node type in %s\n",
			__func__);
		return -EINVAL;

	case AST_OP_AND:
	case AST_OP_OR:
		fprintf(stderr, "[error] Unexpected logical node type in %s\n",
			__func__);
		return -EINVAL;

	case AST_OP_MUL:
		insn.op = FILTER_OP_MUL;
		break;
	case AST_OP_DIV:
		insn.op = FILTER_OP_DIV;
		break;
	case AST_OP_MOD:
		insn.op = FILTER_OP_MOD;
		break;
	case AST_OP_PLUS:
		insn.op = FILTER_OP_PLUS;
		break;
	case AST_OP_MINUS:
		insn.op = FILTER_OP_MINUS;
		break;
	case AST_OP_RSHIFT:
		insn.op = FILTER_OP_RSHIFT;
		break;
	case AST_OP_LSHIFT:
		insn.op = FILTER_OP_LSHIFT;
		break;
	case AST_OP_BIN_AND:
		insn.op = FILTER_OP_BIN_AND;
		break;
	case AST_OP_BIN_OR:
		insn.op = FILTER_OP_BIN_OR;
		break;
	case AST_OP_BIN_XOR:
		insn.op = FILTER_OP_BIN_XOR;
		break;

	case AST_OP_EQ:
		insn.op = FILTER_OP_EQ;
		break;
	case AST_OP_NE:
		insn.op = FILTER_OP_NE;
		break;
	case AST_OP_GT:
		insn.op = FILTER_OP_GT;
		break;
	case AST_OP_LT:
		insn.op = FILTER_OP_LT;
		break;
	case AST_OP_GE:
		insn.op = FILTER_OP_GE;
		break;
	case AST_OP_LE:
		insn.op = FILTER_OP_LE;
		break;
	}
	return bytecode_push(&ctx->bytecode, &insn, 1, sizeof(insn));
}

/*
 * A logical op always return a s64 (1 or 0).
 */
static
int visit_node_logical(struct filter_parser_ctx *ctx, struct ir_op *node)
{
	int ret;
	struct logical_op insn;
	uint16_t skip_offset_loc;
	uint16_t target_loc;

	/* Visit left child */
	ret = recursive_visit_gen_bytecode(ctx, node->u.binary.left);
	if (ret)
		return ret;
	/* Cast to s64 if float or field ref */
	if (node->u.binary.left->data_type == IR_DATA_FIELD_REF
			|| node->u.binary.left->data_type == IR_DATA_FLOAT) {
		struct cast_op cast_insn;

		if (node->u.binary.left->data_type == IR_DATA_FIELD_REF) {
			cast_insn.op = FILTER_OP_CAST_TO_S64;
		} else {
			cast_insn.op = FILTER_OP_CAST_DOUBLE_TO_S64;
		}
		ret = bytecode_push(&ctx->bytecode, &cast_insn,
					1, sizeof(cast_insn));
		if (ret)
			return ret;
	}
	switch (node->u.logical.type) {
	default:
		fprintf(stderr, "[error] Unknown node type in %s\n",
			__func__);
		return -EINVAL;

	case AST_OP_AND:
		insn.op = FILTER_OP_AND;
		break;
	case AST_OP_OR:
		insn.op = FILTER_OP_OR;
		break;
	}
	insn.skip_offset = (uint16_t) -1UL;	/* Temporary */
	ret = bytecode_push_logical(&ctx->bytecode, &insn, 1, sizeof(insn),
			&skip_offset_loc);
	if (ret)
		return ret;
	/* Visit right child */
	ret = recursive_visit_gen_bytecode(ctx, node->u.binary.right);
	if (ret)
		return ret;
	/* Cast to s64 if float or field ref */
	if (node->u.binary.right->data_type == IR_DATA_FIELD_REF
			|| node->u.binary.right->data_type == IR_DATA_FLOAT) {
		struct cast_op cast_insn;

		if (node->u.binary.right->data_type == IR_DATA_FIELD_REF) {
			cast_insn.op = FILTER_OP_CAST_TO_S64;
		} else {
			cast_insn.op = FILTER_OP_CAST_DOUBLE_TO_S64;
		}
		ret = bytecode_push(&ctx->bytecode, &cast_insn,
					1, sizeof(cast_insn));
		if (ret)
			return ret;
	}
	/* We now know where the logical op can skip. */
	target_loc = (uint16_t) bytecode_get_len(&ctx->bytecode->b);
	ret = bytecode_patch(&ctx->bytecode,
			&target_loc,			/* Offset to jump to */
			skip_offset_loc,		/* Where to patch */
			sizeof(uint16_t));
	return ret;
}

/*
 * Postorder traversal of the tree. We need the children result before
 * we can evaluate the parent.
 */
static
int recursive_visit_gen_bytecode(struct filter_parser_ctx *ctx,
		struct ir_op *node)
{
	switch (node->op) {
	case IR_OP_UNKNOWN:
	default:
		fprintf(stderr, "[error] Unknown node type in %s\n",
			__func__);
		return -EINVAL;

	case IR_OP_ROOT:
		return visit_node_root(ctx, node);
	case IR_OP_LOAD:
		return visit_node_load(ctx, node);
	case IR_OP_UNARY:
		return visit_node_unary(ctx, node);
	case IR_OP_BINARY:
		return visit_node_binary(ctx, node);
	case IR_OP_LOGICAL:
		return visit_node_logical(ctx, node);
	}
}

__attribute__((visibility("hidden")))
void filter_bytecode_free(struct filter_parser_ctx *ctx)
{
	free(ctx->bytecode);
	ctx->bytecode = NULL;
	free(ctx->bytecode_reloc);
	ctx->bytecode_reloc = NULL;
}

__attribute__((visibility("hidden")))
int filter_visitor_bytecode_generate(struct filter_parser_ctx *ctx)
{
	int ret;

	ret = bytecode_init(&ctx->bytecode);
	if (ret)
		return ret;
	ret = bytecode_init(&ctx->bytecode_reloc);
	if (ret)
		goto error;
	ret = recursive_visit_gen_bytecode(ctx, ctx->ir_root);
	if (ret)
		goto error;

	/* Finally, append symbol table to bytecode */
	ctx->bytecode->b.reloc_table_offset = bytecode_get_len(&ctx->bytecode->b);
	return bytecode_push(&ctx->bytecode, ctx->bytecode_reloc->b.data,
			1, bytecode_get_len(&ctx->bytecode_reloc->b));

error:
	filter_bytecode_free(ctx);
	return ret;
}
Commit	Line	Data
953192ba MD	1	/*
	2	* filter-visitor-generate-bytecode.c
	3	*
	4	* LTTng filter bytecode generation
	5	*
	6	* Copyright 2012 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
	7	*
	8	* This library is free software; you can redistribute it and/or modify it
	9	* under the terms of the GNU Lesser General Public License, version 2.1 only,
	10	* as published by the Free Software Foundation.
	11	*
	12	* This library is distributed in the hope that it will be useful,
	13	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	15	* Lesser General Public License for more details.
	16	*
	17	* You should have received a copy of the GNU Lesser General Public License
	18	* along with this library; if not, write to the Free Software Foundation,
	19	* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
	20	*/
	21
	22	#include <stdlib.h>
	23	#include <string.h>
	24	#include <errno.h>
	25	#include "align.h"
	26	#include "filter-bytecode.h"
	27	#include "filter-ir.h"
	28	#include "filter-ast.h"
	29
	30	#ifndef max_t
	31	#define max_t(type, a, b) ((type) ((a) > (b) ? (a) : (b)))
	32	#endif
	33
	34	//#define INIT_ALLOC_SIZE PAGE_SIZE
	35	#define INIT_ALLOC_SIZE 4
	36
	37	static
	38	int recursive_visit_gen_bytecode(struct filter_parser_ctx *ctx,
	39	struct ir_op *node);
	40
01a204f0 CB	41	static inline int fls(unsigned int x)
	42	{
	43	int r = 32;
	44
	45	if (!x)
	46	return 0;
	47	if (!(x & 0xFFFF0000U)) {
	48	x <<= 16;
	49	r -= 16;
	50	}
	51	if (!(x & 0xFF000000U)) {
	52	x <<= 8;
	53	r -= 8;
	54	}
	55	if (!(x & 0xF0000000U)) {
	56	x <<= 4;
	57	r -= 4;
	58	}
	59	if (!(x & 0xC0000000U)) {
	60	x <<= 2;
	61	r -= 2;
	62	}
	63	if (!(x & 0x80000000U)) {
	64	x <<= 1;
	65	r -= 1;
	66	}
	67	return r;
	68	}
	69
	70	static inline int get_count_order(unsigned int count)
	71	{
	72	int order;
	73
	74	order = fls(count) - 1;
	75	if (count & (count - 1))
	76	order++;
	77	return order;
	78	}
	79
953192ba	80	static
53a80697	81	int bytecode_init(struct lttng_filter_bytecode_alloc **fb)
953192ba	82	{
1029587a MD	83	uint32_t alloc_len;
	84
	85	alloc_len = sizeof(struct lttng_filter_bytecode_alloc) + INIT_ALLOC_SIZE;
	86	*fb = calloc(alloc_len, 1);
953192ba MD	87	if (!*fb) {
	88	return -ENOMEM;
	89	} else {
1029587a	90	(*fb)->alloc_len = alloc_len;
953192ba MD	91	return 0;
	92	}
	93	}
	94
	95	static
53a80697	96	int32_t bytecode_reserve(struct lttng_filter_bytecode_alloc **fb, uint32_t align, uint32_t len)
953192ba MD	97	{
	98	int32_t ret;
	99	uint32_t padding = offset_align((*fb)->b.len, align);
ec96a8f6	100	uint32_t new_len = (*fb)->b.len + padding + len;
1029587a	101	uint32_t new_alloc_len = sizeof(struct lttng_filter_bytecode_alloc) + new_len;
ec96a8f6	102	uint32_t old_alloc_len = (*fb)->alloc_len;
953192ba	103
ec96a8f6	104	if (new_len > LTTNG_FILTER_MAX_LEN)
5ddb0a08 CB	105	return -EINVAL;
5ddb0a08 CB	106
ec96a8f6 MD	107	if (new_alloc_len > old_alloc_len) {
	108	new_alloc_len =
	109	max_t(uint32_t, 1U << get_count_order(new_alloc_len), old_alloc_len << 1);
	110	fb = realloc(fb, new_alloc_len);
953192ba MD	111	if (!*fb)
953192ba MD	112	return -ENOMEM;
1029587a	113	/* We zero directly the memory from start of allocation. */
ec96a8f6 MD	114	memset(&((char ) fb)[old_alloc_len], 0, new_alloc_len - old_alloc_len);
ec96a8f6 MD	115	(*fb)->alloc_len = new_alloc_len;
953192ba MD	116	}
	117	(*fb)->b.len += padding;
	118	ret = (*fb)->b.len;
	119	(*fb)->b.len += len;
	120	return ret;
	121	}
	122
	123	static
53a80697	124	int bytecode_push(struct lttng_filter_bytecode_alloc *fb, const void data,
953192ba MD	125	uint32_t align, uint32_t len)
	126	{
	127	int32_t offset;
	128
	129	offset = bytecode_reserve(fb, align, len);
	130	if (offset < 0)
	131	return offset;
	132	memcpy(&(*fb)->b.data[offset], data, len);
	133	return 0;
	134	}
	135
	136	static
53a80697	137	int bytecode_push_logical(struct lttng_filter_bytecode_alloc **fb,
953192ba MD	138	struct logical_op *data,
	139	uint32_t align, uint32_t len,
	140	uint16_t *skip_offset)
	141	{
	142	int32_t offset;
	143
	144	offset = bytecode_reserve(fb, align, len);
	145	if (offset < 0)
	146	return offset;
	147	memcpy(&(*fb)->b.data[offset], data, len);
	148	*skip_offset =
	149	(void ) &((struct logical_op ) &(*fb)->b.data[offset])->skip_offset
	150	- (void ) &(fb)->b.data[0];
	151	return 0;
	152	}
	153
	154	static
53a80697	155	int bytecode_patch(struct lttng_filter_bytecode_alloc **fb,
953192ba MD	156	const void *data,
	157	uint16_t offset,
	158	uint32_t len)
	159	{
	160	if (offset >= (*fb)->b.len) {
	161	return -EINVAL;
	162	}
	163	memcpy(&(*fb)->b.data[offset], data, len);
	164	return 0;
	165	}
	166
	167	static
	168	int visit_node_root(struct filter_parser_ctx ctx, struct ir_op node)
	169	{
	170	int ret;
	171	struct return_op insn;
	172
	173	/* Visit child */
	174	ret = recursive_visit_gen_bytecode(ctx, node->u.root.child);
	175	if (ret)
	176	return ret;
	177
	178	/* Generate end of bytecode instruction */
	179	insn.op = FILTER_OP_RETURN;
	180	return bytecode_push(&ctx->bytecode, &insn, 1, sizeof(insn));
	181	}
	182
953192ba MD	183	static
	184	int visit_node_load(struct filter_parser_ctx ctx, struct ir_op node)
	185	{
	186	int ret;
	187
	188	switch (node->data_type) {
	189	case IR_DATA_UNKNOWN:
	190	default:
	191	fprintf(stderr, "[error] Unknown data type in %s\n",
	192	__func__);
	193	return -EINVAL;
	194
	195	case IR_DATA_STRING:
	196	{
	197	struct load_op *insn;
	198	uint32_t insn_len = sizeof(struct load_op)
	199	+ strlen(node->u.load.u.string) + 1;
	200
	201	insn = calloc(insn_len, 1);
	202	if (!insn)
	203	return -ENOMEM;
	204	insn->op = FILTER_OP_LOAD_STRING;
953192ba MD	205	strcpy(insn->data, node->u.load.u.string);
	206	ret = bytecode_push(&ctx->bytecode, insn, 1, insn_len);
	207	free(insn);
	208	return ret;
	209	}
	210	case IR_DATA_NUMERIC:
	211	{
	212	struct load_op *insn;
	213	uint32_t insn_len = sizeof(struct load_op)
	214	+ sizeof(struct literal_numeric);
	215
	216	insn = calloc(insn_len, 1);
	217	if (!insn)
	218	return -ENOMEM;
	219	insn->op = FILTER_OP_LOAD_S64;
953192ba MD	220	(int64_t ) insn->data = node->u.load.u.num;
	221	ret = bytecode_push(&ctx->bytecode, insn, 1, insn_len);
	222	free(insn);
	223	return ret;
	224	}
e90d8561 MD	225	case IR_DATA_FLOAT:
	226	{
	227	struct load_op *insn;
	228	uint32_t insn_len = sizeof(struct load_op)
	229	+ sizeof(struct literal_double);
	230
	231	insn = calloc(insn_len, 1);
	232	if (!insn)
	233	return -ENOMEM;
	234	insn->op = FILTER_OP_LOAD_DOUBLE;
e90d8561 MD	235	(double ) insn->data = node->u.load.u.flt;
	236	ret = bytecode_push(&ctx->bytecode, insn, 1, insn_len);
	237	free(insn);
	238	return ret;
	239	}
953192ba MD	240	case IR_DATA_FIELD_REF:
	241	{
	242	struct load_op *insn;
	243	uint32_t insn_len = sizeof(struct load_op)
	244	+ sizeof(struct field_ref);
	245	struct field_ref ref_offset;
ec96a8f6 MD	246	uint32_t reloc_offset_u32;
ec96a8f6 MD	247	uint16_t reloc_offset;
953192ba MD	248
	249	insn = calloc(insn_len, 1);
	250	if (!insn)
	251	return -ENOMEM;
	252	insn->op = FILTER_OP_LOAD_FIELD_REF;
953192ba MD	253	ref_offset.offset = (uint16_t) -1U;
953192ba MD	254	memcpy(insn->data, &ref_offset, sizeof(ref_offset));
65775683	255	/* reloc_offset points to struct load_op */
ec96a8f6 MD	256	reloc_offset_u32 = bytecode_get_len(&ctx->bytecode->b);
	257	if (reloc_offset_u32 > LTTNG_FILTER_MAX_LEN - 1) {
	258	free(insn);
	259	return -EINVAL;
	260	}
	261	reloc_offset = (uint16_t) reloc_offset_u32;
953192ba MD	262	ret = bytecode_push(&ctx->bytecode, insn, 1, insn_len);
	263	if (ret) {
	264	free(insn);
	265	return ret;
	266	}
	267	/* append reloc */
	268	ret = bytecode_push(&ctx->bytecode_reloc, &reloc_offset,
	269	1, sizeof(reloc_offset));
	270	if (ret) {
	271	free(insn);
	272	return ret;
	273	}
	274	ret = bytecode_push(&ctx->bytecode_reloc, node->u.load.u.ref,
	275	1, strlen(node->u.load.u.ref) + 1);
	276	free(insn);
	277	return ret;
	278	}
	279	}
	280	}
	281
	282	static
	283	int visit_node_unary(struct filter_parser_ctx ctx, struct ir_op node)
	284	{
	285	int ret;
	286	struct unary_op insn;
	287
	288	/* Visit child */
	289	ret = recursive_visit_gen_bytecode(ctx, node->u.unary.child);
	290	if (ret)
	291	return ret;
	292
	293	/* Generate end of bytecode instruction */
	294	switch (node->u.unary.type) {
	295	case AST_UNARY_UNKNOWN:
	296	default:
	297	fprintf(stderr, "[error] Unknown unary node type in %s\n",
	298	__func__);
	299	return -EINVAL;
	300	case AST_UNARY_PLUS:
	301	/* Nothing to do. */
	302	return 0;
	303	case AST_UNARY_MINUS:
	304	insn.op = FILTER_OP_UNARY_MINUS;
953192ba MD	305	return bytecode_push(&ctx->bytecode, &insn, 1, sizeof(insn));
	306	case AST_UNARY_NOT:
	307	insn.op = FILTER_OP_UNARY_NOT;
953192ba MD	308	return bytecode_push(&ctx->bytecode, &insn, 1, sizeof(insn));
	309	}
	310	}
	311
	312	/*
	313	* Binary comparator nesting is disallowed. This allows fitting into
	314	* only 2 registers.
	315	*/
	316	static
	317	int visit_node_binary(struct filter_parser_ctx ctx, struct ir_op node)
	318	{
	319	int ret;
	320	struct binary_op insn;
	321
	322	/* Visit child */
	323	ret = recursive_visit_gen_bytecode(ctx, node->u.binary.left);
	324	if (ret)
	325	return ret;
	326	ret = recursive_visit_gen_bytecode(ctx, node->u.binary.right);
	327	if (ret)
	328	return ret;
	329
	330	switch (node->u.binary.type) {
	331	case AST_OP_UNKNOWN:
	332	default:
	333	fprintf(stderr, "[error] Unknown unary node type in %s\n",
	334	__func__);
	335	return -EINVAL;
	336
	337	case AST_OP_AND:
	338	case AST_OP_OR:
	339	fprintf(stderr, "[error] Unexpected logical node type in %s\n",
	340	__func__);
	341	return -EINVAL;
	342
	343	case AST_OP_MUL:
	344	insn.op = FILTER_OP_MUL;
	345	break;
	346	case AST_OP_DIV:
	347	insn.op = FILTER_OP_DIV;
	348	break;
	349	case AST_OP_MOD:
	350	insn.op = FILTER_OP_MOD;
	351	break;
	352	case AST_OP_PLUS:
	353	insn.op = FILTER_OP_PLUS;
	354	break;
	355	case AST_OP_MINUS:
	356	insn.op = FILTER_OP_MINUS;
	357	break;
	358	case AST_OP_RSHIFT:
	359	insn.op = FILTER_OP_RSHIFT;
	360	break;
	361	case AST_OP_LSHIFT:
	362	insn.op = FILTER_OP_LSHIFT;
	363	break;
	364	case AST_OP_BIN_AND:
	365	insn.op = FILTER_OP_BIN_AND;
	366	break;
	367	case AST_OP_BIN_OR:
	368	insn.op = FILTER_OP_BIN_OR;
	369	break;
	370	case AST_OP_BIN_XOR:
	371	insn.op = FILTER_OP_BIN_XOR;
372	break;
373
374	case AST_OP_EQ:
375	insn.op = FILTER_OP_EQ;
376	break;
377	case AST_OP_NE:
378	insn.op = FILTER_OP_NE;
379	break;
380	case AST_OP_GT:
381	insn.op = FILTER_OP_GT;
382	break;
383	case AST_OP_LT:
384	insn.op = FILTER_OP_LT;
385	break;
386	case AST_OP_GE:
387	insn.op = FILTER_OP_GE;
388	break;
389	case AST_OP_LE:
390	insn.op = FILTER_OP_LE;
391	break;
392	}
393	return bytecode_push(&ctx->bytecode, &insn, 1, sizeof(insn));
394	}
395
8cf9540a MD	396	/*
	397	* A logical op always return a s64 (1 or 0).
	398	*/
953192ba MD	399	static
	400	int visit_node_logical(struct filter_parser_ctx ctx, struct ir_op node)
	401	{
	402	int ret;
	403	struct logical_op insn;
	404	uint16_t skip_offset_loc;
	405	uint16_t target_loc;
	406
	407	/* Visit left child */
	408	ret = recursive_visit_gen_bytecode(ctx, node->u.binary.left);
	409	if (ret)
	410	return ret;
8cf9540a MD	411	/* Cast to s64 if float or field ref */
	412	if (node->u.binary.left->data_type == IR_DATA_FIELD_REF
	413	\|\| node->u.binary.left->data_type == IR_DATA_FLOAT) {
	414	struct cast_op cast_insn;
	415
29fefef8 MD	416	if (node->u.binary.left->data_type == IR_DATA_FIELD_REF) {
	417	cast_insn.op = FILTER_OP_CAST_TO_S64;
	418	} else {
	419	cast_insn.op = FILTER_OP_CAST_DOUBLE_TO_S64;
	420	}
8cf9540a MD	421	ret = bytecode_push(&ctx->bytecode, &cast_insn,
	422	1, sizeof(cast_insn));
	423	if (ret)
	424	return ret;
	425	}
953192ba MD	426	switch (node->u.logical.type) {
	427	default:
	428	fprintf(stderr, "[error] Unknown node type in %s\n",
	429	__func__);
	430	return -EINVAL;
	431
	432	case AST_OP_AND:
	433	insn.op = FILTER_OP_AND;
	434	break;
	435	case AST_OP_OR:
	436	insn.op = FILTER_OP_OR;
	437	break;
	438	}
	439	insn.skip_offset = (uint16_t) -1UL; /* Temporary */
	440	ret = bytecode_push_logical(&ctx->bytecode, &insn, 1, sizeof(insn),
	441	&skip_offset_loc);
	442	if (ret)
	443	return ret;
	444	/* Visit right child */
	445	ret = recursive_visit_gen_bytecode(ctx, node->u.binary.right);
	446	if (ret)
	447	return ret;
8cf9540a MD	448	/* Cast to s64 if float or field ref */
	449	if (node->u.binary.right->data_type == IR_DATA_FIELD_REF
	450	\|\| node->u.binary.right->data_type == IR_DATA_FLOAT) {
	451	struct cast_op cast_insn;
	452
29fefef8 MD	453	if (node->u.binary.right->data_type == IR_DATA_FIELD_REF) {
	454	cast_insn.op = FILTER_OP_CAST_TO_S64;
	455	} else {
	456	cast_insn.op = FILTER_OP_CAST_DOUBLE_TO_S64;
	457	}
8cf9540a MD	458	ret = bytecode_push(&ctx->bytecode, &cast_insn,
	459	1, sizeof(cast_insn));
	460	if (ret)
	461	return ret;
	462	}
953192ba MD	463	/* We now know where the logical op can skip. */
	464	target_loc = (uint16_t) bytecode_get_len(&ctx->bytecode->b);
	465	ret = bytecode_patch(&ctx->bytecode,
	466	&target_loc, /* Offset to jump to */
	467	skip_offset_loc, /* Where to patch */
	468	sizeof(uint16_t));
	469	return ret;
	470	}
	471
	472	/*
	473	* Postorder traversal of the tree. We need the children result before
	474	* we can evaluate the parent.
	475	*/
	476	static
	477	int recursive_visit_gen_bytecode(struct filter_parser_ctx *ctx,
	478	struct ir_op *node)
	479	{
	480	switch (node->op) {
	481	case IR_OP_UNKNOWN:
	482	default:
	483	fprintf(stderr, "[error] Unknown node type in %s\n",
	484	__func__);
	485	return -EINVAL;
	486
	487	case IR_OP_ROOT:
	488	return visit_node_root(ctx, node);
	489	case IR_OP_LOAD:
	490	return visit_node_load(ctx, node);
	491	case IR_OP_UNARY:
	492	return visit_node_unary(ctx, node);
	493	case IR_OP_BINARY:
	494	return visit_node_binary(ctx, node);
	495	case IR_OP_LOGICAL:
	496	return visit_node_logical(ctx, node);
	497	}
	498	}
	499
d00c599e	500	__attribute__((visibility("hidden")))
953192ba MD	501	void filter_bytecode_free(struct filter_parser_ctx *ctx)
	502	{
	503	free(ctx->bytecode);
	504	ctx->bytecode = NULL;
	505	free(ctx->bytecode_reloc);
	506	ctx->bytecode_reloc = NULL;
	507	}
	508
d00c599e	509	__attribute__((visibility("hidden")))
953192ba MD	510	int filter_visitor_bytecode_generate(struct filter_parser_ctx *ctx)
	511	{
	512	int ret;
	513
	514	ret = bytecode_init(&ctx->bytecode);
	515	if (ret)
	516	return ret;
	517	ret = bytecode_init(&ctx->bytecode_reloc);
	518	if (ret)
	519	goto error;
	520	ret = recursive_visit_gen_bytecode(ctx, ctx->ir_root);
	521	if (ret)
	522	goto error;
	523
	524	/* Finally, append symbol table to bytecode */
	525	ctx->bytecode->b.reloc_table_offset = bytecode_get_len(&ctx->bytecode->b);
	526	return bytecode_push(&ctx->bytecode, ctx->bytecode_reloc->b.data,
	527	1, bytecode_get_len(&ctx->bytecode_reloc->b));
	528
	529	error:
	530	filter_bytecode_free(ctx);
	531	return ret;
	532	}