[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"

#include <common/macros.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);
	}
}

LTTNG_HIDDEN
void filter_bytecode_free(struct filter_parser_ctx *ctx)
{
	free(ctx->bytecode);
	ctx->bytecode = NULL;
	free(ctx->bytecode_reloc);
	ctx->bytecode_reloc = NULL;
}

LTTNG_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
a187da1a DG	30	#include <common/macros.h>
a187da1a DG	31
953192ba MD	32	#ifndef max_t
	33	#define max_t(type, a, b) ((type) ((a) > (b) ? (a) : (b)))
	34	#endif
	35
	36	//#define INIT_ALLOC_SIZE PAGE_SIZE
	37	#define INIT_ALLOC_SIZE 4
	38
	39	static
	40	int recursive_visit_gen_bytecode(struct filter_parser_ctx *ctx,
	41	struct ir_op *node);
	42
01a204f0 CB	43	static inline int fls(unsigned int x)
	44	{
	45	int r = 32;
	46
	47	if (!x)
	48	return 0;
	49	if (!(x & 0xFFFF0000U)) {
	50	x <<= 16;
	51	r -= 16;
	52	}
	53	if (!(x & 0xFF000000U)) {
	54	x <<= 8;
	55	r -= 8;
	56	}
	57	if (!(x & 0xF0000000U)) {
	58	x <<= 4;
	59	r -= 4;
	60	}
	61	if (!(x & 0xC0000000U)) {
	62	x <<= 2;
	63	r -= 2;
	64	}
	65	if (!(x & 0x80000000U)) {
	66	x <<= 1;
	67	r -= 1;
	68	}
	69	return r;
	70	}
	71
	72	static inline int get_count_order(unsigned int count)
	73	{
	74	int order;
	75
	76	order = fls(count) - 1;
	77	if (count & (count - 1))
	78	order++;
	79	return order;
	80	}
	81
953192ba	82	static
53a80697	83	int bytecode_init(struct lttng_filter_bytecode_alloc **fb)
953192ba	84	{
1029587a MD	85	uint32_t alloc_len;
	86
	87	alloc_len = sizeof(struct lttng_filter_bytecode_alloc) + INIT_ALLOC_SIZE;
	88	*fb = calloc(alloc_len, 1);
953192ba MD	89	if (!*fb) {
	90	return -ENOMEM;
	91	} else {
1029587a	92	(*fb)->alloc_len = alloc_len;
953192ba MD	93	return 0;
	94	}
	95	}
	96
	97	static
53a80697	98	int32_t bytecode_reserve(struct lttng_filter_bytecode_alloc **fb, uint32_t align, uint32_t len)
953192ba MD	99	{
	100	int32_t ret;
	101	uint32_t padding = offset_align((*fb)->b.len, align);
ec96a8f6	102	uint32_t new_len = (*fb)->b.len + padding + len;
1029587a	103	uint32_t new_alloc_len = sizeof(struct lttng_filter_bytecode_alloc) + new_len;
ec96a8f6	104	uint32_t old_alloc_len = (*fb)->alloc_len;
953192ba	105
ec96a8f6	106	if (new_len > LTTNG_FILTER_MAX_LEN)
5ddb0a08 CB	107	return -EINVAL;
5ddb0a08 CB	108
ec96a8f6 MD	109	if (new_alloc_len > old_alloc_len) {
	110	new_alloc_len =
	111	max_t(uint32_t, 1U << get_count_order(new_alloc_len), old_alloc_len << 1);
	112	fb = realloc(fb, new_alloc_len);
953192ba MD	113	if (!*fb)
953192ba MD	114	return -ENOMEM;
1029587a	115	/* We zero directly the memory from start of allocation. */
ec96a8f6 MD	116	memset(&((char ) fb)[old_alloc_len], 0, new_alloc_len - old_alloc_len);
ec96a8f6 MD	117	(*fb)->alloc_len = new_alloc_len;
953192ba MD	118	}
	119	(*fb)->b.len += padding;
	120	ret = (*fb)->b.len;
	121	(*fb)->b.len += len;
	122	return ret;
	123	}
	124
	125	static
53a80697	126	int bytecode_push(struct lttng_filter_bytecode_alloc *fb, const void data,
953192ba MD	127	uint32_t align, uint32_t len)
	128	{
	129	int32_t offset;
	130
	131	offset = bytecode_reserve(fb, align, len);
	132	if (offset < 0)
	133	return offset;
	134	memcpy(&(*fb)->b.data[offset], data, len);
	135	return 0;
	136	}
	137
	138	static
53a80697	139	int bytecode_push_logical(struct lttng_filter_bytecode_alloc **fb,
953192ba MD	140	struct logical_op *data,
	141	uint32_t align, uint32_t len,
	142	uint16_t *skip_offset)
	143	{
	144	int32_t offset;
	145
	146	offset = bytecode_reserve(fb, align, len);
	147	if (offset < 0)
	148	return offset;
	149	memcpy(&(*fb)->b.data[offset], data, len);
	150	*skip_offset =
	151	(void ) &((struct logical_op ) &(*fb)->b.data[offset])->skip_offset
	152	- (void ) &(fb)->b.data[0];
	153	return 0;
	154	}
	155
	156	static
53a80697	157	int bytecode_patch(struct lttng_filter_bytecode_alloc **fb,
953192ba MD	158	const void *data,
	159	uint16_t offset,
	160	uint32_t len)
	161	{
	162	if (offset >= (*fb)->b.len) {
	163	return -EINVAL;
	164	}
	165	memcpy(&(*fb)->b.data[offset], data, len);
	166	return 0;
	167	}
	168
	169	static
	170	int visit_node_root(struct filter_parser_ctx ctx, struct ir_op node)
	171	{
	172	int ret;
	173	struct return_op insn;
	174
	175	/* Visit child */
	176	ret = recursive_visit_gen_bytecode(ctx, node->u.root.child);
	177	if (ret)
	178	return ret;
	179
	180	/* Generate end of bytecode instruction */
	181	insn.op = FILTER_OP_RETURN;
	182	return bytecode_push(&ctx->bytecode, &insn, 1, sizeof(insn));
	183	}
	184
953192ba MD	185	static
	186	int visit_node_load(struct filter_parser_ctx ctx, struct ir_op node)
	187	{
	188	int ret;
	189
	190	switch (node->data_type) {
	191	case IR_DATA_UNKNOWN:
	192	default:
	193	fprintf(stderr, "[error] Unknown data type in %s\n",
	194	__func__);
	195	return -EINVAL;
	196
	197	case IR_DATA_STRING:
	198	{
	199	struct load_op *insn;
	200	uint32_t insn_len = sizeof(struct load_op)
	201	+ strlen(node->u.load.u.string) + 1;
	202
	203	insn = calloc(insn_len, 1);
	204	if (!insn)
	205	return -ENOMEM;
	206	insn->op = FILTER_OP_LOAD_STRING;
953192ba MD	207	strcpy(insn->data, node->u.load.u.string);
	208	ret = bytecode_push(&ctx->bytecode, insn, 1, insn_len);
	209	free(insn);
	210	return ret;
	211	}
	212	case IR_DATA_NUMERIC:
	213	{
	214	struct load_op *insn;
	215	uint32_t insn_len = sizeof(struct load_op)
	216	+ sizeof(struct literal_numeric);
	217
	218	insn = calloc(insn_len, 1);
	219	if (!insn)
	220	return -ENOMEM;
	221	insn->op = FILTER_OP_LOAD_S64;
953192ba MD	222	(int64_t ) insn->data = node->u.load.u.num;
	223	ret = bytecode_push(&ctx->bytecode, insn, 1, insn_len);
	224	free(insn);
	225	return ret;
	226	}
e90d8561 MD	227	case IR_DATA_FLOAT:
	228	{
	229	struct load_op *insn;
	230	uint32_t insn_len = sizeof(struct load_op)
	231	+ sizeof(struct literal_double);
	232
	233	insn = calloc(insn_len, 1);
	234	if (!insn)
	235	return -ENOMEM;
	236	insn->op = FILTER_OP_LOAD_DOUBLE;
e90d8561 MD	237	(double ) insn->data = node->u.load.u.flt;
	238	ret = bytecode_push(&ctx->bytecode, insn, 1, insn_len);
	239	free(insn);
	240	return ret;
	241	}
953192ba MD	242	case IR_DATA_FIELD_REF:
	243	{
	244	struct load_op *insn;
	245	uint32_t insn_len = sizeof(struct load_op)
	246	+ sizeof(struct field_ref);
	247	struct field_ref ref_offset;
ec96a8f6 MD	248	uint32_t reloc_offset_u32;
ec96a8f6 MD	249	uint16_t reloc_offset;
953192ba MD	250
	251	insn = calloc(insn_len, 1);
	252	if (!insn)
	253	return -ENOMEM;
	254	insn->op = FILTER_OP_LOAD_FIELD_REF;
953192ba MD	255	ref_offset.offset = (uint16_t) -1U;
953192ba MD	256	memcpy(insn->data, &ref_offset, sizeof(ref_offset));
65775683	257	/* reloc_offset points to struct load_op */
ec96a8f6 MD	258	reloc_offset_u32 = bytecode_get_len(&ctx->bytecode->b);
	259	if (reloc_offset_u32 > LTTNG_FILTER_MAX_LEN - 1) {
	260	free(insn);
	261	return -EINVAL;
	262	}
	263	reloc_offset = (uint16_t) reloc_offset_u32;
953192ba MD	264	ret = bytecode_push(&ctx->bytecode, insn, 1, insn_len);
	265	if (ret) {
	266	free(insn);
	267	return ret;
	268	}
	269	/* append reloc */
	270	ret = bytecode_push(&ctx->bytecode_reloc, &reloc_offset,
	271	1, sizeof(reloc_offset));
	272	if (ret) {
	273	free(insn);
	274	return ret;
	275	}
	276	ret = bytecode_push(&ctx->bytecode_reloc, node->u.load.u.ref,
	277	1, strlen(node->u.load.u.ref) + 1);
	278	free(insn);
	279	return ret;
	280	}
	281	}
	282	}
	283
	284	static
	285	int visit_node_unary(struct filter_parser_ctx ctx, struct ir_op node)
	286	{
	287	int ret;
	288	struct unary_op insn;
	289
	290	/* Visit child */
	291	ret = recursive_visit_gen_bytecode(ctx, node->u.unary.child);
	292	if (ret)
	293	return ret;
	294
	295	/* Generate end of bytecode instruction */
	296	switch (node->u.unary.type) {
	297	case AST_UNARY_UNKNOWN:
	298	default:
	299	fprintf(stderr, "[error] Unknown unary node type in %s\n",
	300	__func__);
	301	return -EINVAL;
	302	case AST_UNARY_PLUS:
	303	/* Nothing to do. */
	304	return 0;
	305	case AST_UNARY_MINUS:
	306	insn.op = FILTER_OP_UNARY_MINUS;
953192ba MD	307	return bytecode_push(&ctx->bytecode, &insn, 1, sizeof(insn));
	308	case AST_UNARY_NOT:
	309	insn.op = FILTER_OP_UNARY_NOT;
953192ba MD	310	return bytecode_push(&ctx->bytecode, &insn, 1, sizeof(insn));
	311	}
	312	}
	313
	314	/*
	315	* Binary comparator nesting is disallowed. This allows fitting into
	316	* only 2 registers.
	317	*/
	318	static
	319	int visit_node_binary(struct filter_parser_ctx ctx, struct ir_op node)
	320	{
	321	int ret;
	322	struct binary_op insn;
	323
	324	/* Visit child */
	325	ret = recursive_visit_gen_bytecode(ctx, node->u.binary.left);
	326	if (ret)
	327	return ret;
	328	ret = recursive_visit_gen_bytecode(ctx, node->u.binary.right);
	329	if (ret)
	330	return ret;
	331
	332	switch (node->u.binary.type) {
	333	case AST_OP_UNKNOWN:
	334	default:
	335	fprintf(stderr, "[error] Unknown unary node type in %s\n",
	336	__func__);
	337	return -EINVAL;
	338
	339	case AST_OP_AND:
	340	case AST_OP_OR:
	341	fprintf(stderr, "[error] Unexpected logical node type in %s\n",
	342	__func__);
	343	return -EINVAL;
	344
	345	case AST_OP_MUL:
	346	insn.op = FILTER_OP_MUL;
	347	break;
	348	case AST_OP_DIV:
	349	insn.op = FILTER_OP_DIV;
	350	break;
	351	case AST_OP_MOD:
	352	insn.op = FILTER_OP_MOD;
	353	break;
	354	case AST_OP_PLUS:
	355	insn.op = FILTER_OP_PLUS;
	356	break;
	357	case AST_OP_MINUS:
	358	insn.op = FILTER_OP_MINUS;
	359	break;
	360	case AST_OP_RSHIFT:
	361	insn.op = FILTER_OP_RSHIFT;
	362	break;
	363	case AST_OP_LSHIFT:
	364	insn.op = FILTER_OP_LSHIFT;
	365	break;
	366	case AST_OP_BIN_AND:
	367	insn.op = FILTER_OP_BIN_AND;
	368	break;
	369	case AST_OP_BIN_OR:
	370	insn.op = FILTER_OP_BIN_OR;
	371	break;
	372	case AST_OP_BIN_XOR:
	373	insn.op = FILTER_OP_BIN_XOR;
374	break;
375
376	case AST_OP_EQ:
377	insn.op = FILTER_OP_EQ;
378	break;
379	case AST_OP_NE:
380	insn.op = FILTER_OP_NE;
381	break;
382	case AST_OP_GT:
383	insn.op = FILTER_OP_GT;
384	break;
385	case AST_OP_LT:
386	insn.op = FILTER_OP_LT;
387	break;
388	case AST_OP_GE:
389	insn.op = FILTER_OP_GE;
390	break;
391	case AST_OP_LE:
392	insn.op = FILTER_OP_LE;
393	break;
394	}
395	return bytecode_push(&ctx->bytecode, &insn, 1, sizeof(insn));
396	}
397
8cf9540a MD	398	/*
	399	* A logical op always return a s64 (1 or 0).
	400	*/
953192ba MD	401	static
	402	int visit_node_logical(struct filter_parser_ctx ctx, struct ir_op node)
	403	{
	404	int ret;
	405	struct logical_op insn;
	406	uint16_t skip_offset_loc;
	407	uint16_t target_loc;
	408
	409	/* Visit left child */
	410	ret = recursive_visit_gen_bytecode(ctx, node->u.binary.left);
	411	if (ret)
	412	return ret;
8cf9540a MD	413	/* Cast to s64 if float or field ref */
	414	if (node->u.binary.left->data_type == IR_DATA_FIELD_REF
	415	\|\| node->u.binary.left->data_type == IR_DATA_FLOAT) {
	416	struct cast_op cast_insn;
	417
29fefef8 MD	418	if (node->u.binary.left->data_type == IR_DATA_FIELD_REF) {
	419	cast_insn.op = FILTER_OP_CAST_TO_S64;
	420	} else {
	421	cast_insn.op = FILTER_OP_CAST_DOUBLE_TO_S64;
	422	}
8cf9540a MD	423	ret = bytecode_push(&ctx->bytecode, &cast_insn,
	424	1, sizeof(cast_insn));
	425	if (ret)
	426	return ret;
	427	}
953192ba MD	428	switch (node->u.logical.type) {
	429	default:
	430	fprintf(stderr, "[error] Unknown node type in %s\n",
	431	__func__);
	432	return -EINVAL;
	433
	434	case AST_OP_AND:
	435	insn.op = FILTER_OP_AND;
	436	break;
	437	case AST_OP_OR:
	438	insn.op = FILTER_OP_OR;
	439	break;
	440	}
	441	insn.skip_offset = (uint16_t) -1UL; /* Temporary */
	442	ret = bytecode_push_logical(&ctx->bytecode, &insn, 1, sizeof(insn),
	443	&skip_offset_loc);
	444	if (ret)
	445	return ret;
	446	/* Visit right child */
	447	ret = recursive_visit_gen_bytecode(ctx, node->u.binary.right);
	448	if (ret)
	449	return ret;
8cf9540a MD	450	/* Cast to s64 if float or field ref */
	451	if (node->u.binary.right->data_type == IR_DATA_FIELD_REF
	452	\|\| node->u.binary.right->data_type == IR_DATA_FLOAT) {
	453	struct cast_op cast_insn;
	454
29fefef8 MD	455	if (node->u.binary.right->data_type == IR_DATA_FIELD_REF) {
	456	cast_insn.op = FILTER_OP_CAST_TO_S64;
	457	} else {
	458	cast_insn.op = FILTER_OP_CAST_DOUBLE_TO_S64;
	459	}
8cf9540a MD	460	ret = bytecode_push(&ctx->bytecode, &cast_insn,
	461	1, sizeof(cast_insn));
	462	if (ret)
	463	return ret;
	464	}
953192ba MD	465	/* We now know where the logical op can skip. */
	466	target_loc = (uint16_t) bytecode_get_len(&ctx->bytecode->b);
	467	ret = bytecode_patch(&ctx->bytecode,
	468	&target_loc, /* Offset to jump to */
	469	skip_offset_loc, /* Where to patch */
	470	sizeof(uint16_t));
	471	return ret;
	472	}
	473
	474	/*
	475	* Postorder traversal of the tree. We need the children result before
	476	* we can evaluate the parent.
	477	*/
	478	static
	479	int recursive_visit_gen_bytecode(struct filter_parser_ctx *ctx,
	480	struct ir_op *node)
	481	{
	482	switch (node->op) {
	483	case IR_OP_UNKNOWN:
	484	default:
	485	fprintf(stderr, "[error] Unknown node type in %s\n",
	486	__func__);
	487	return -EINVAL;
	488
	489	case IR_OP_ROOT:
	490	return visit_node_root(ctx, node);
	491	case IR_OP_LOAD:
	492	return visit_node_load(ctx, node);
	493	case IR_OP_UNARY:
	494	return visit_node_unary(ctx, node);
	495	case IR_OP_BINARY:
	496	return visit_node_binary(ctx, node);
	497	case IR_OP_LOGICAL:
	498	return visit_node_logical(ctx, node);
	499	}
	500	}
	501
a187da1a	502	LTTNG_HIDDEN
953192ba MD	503	void filter_bytecode_free(struct filter_parser_ctx *ctx)
	504	{
	505	free(ctx->bytecode);
	506	ctx->bytecode = NULL;
	507	free(ctx->bytecode_reloc);
	508	ctx->bytecode_reloc = NULL;
	509	}
	510
a187da1a	511	LTTNG_HIDDEN
953192ba MD	512	int filter_visitor_bytecode_generate(struct filter_parser_ctx *ctx)
	513	{
	514	int ret;
	515
	516	ret = bytecode_init(&ctx->bytecode);
	517	if (ret)
	518	return ret;
	519	ret = bytecode_init(&ctx->bytecode_reloc);
	520	if (ret)
	521	goto error;
	522	ret = recursive_visit_gen_bytecode(ctx, ctx->ir_root);
	523	if (ret)
	524	goto error;
	525
	526	/* Finally, append symbol table to bytecode */
	527	ctx->bytecode->b.reloc_table_offset = bytecode_get_len(&ctx->bytecode->b);
	528	return bytecode_push(&ctx->bytecode, ctx->bytecode_reloc->b.data,
	529	1, bytecode_get_len(&ctx->bytecode_reloc->b));
	530
	531	error:
	532	filter_bytecode_free(ctx);
	533	return ret;
	534	}