[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) {
		struct lttng_filter_bytecode_alloc *newptr;

		new_alloc_len =
			max_t(uint32_t, 1U << get_count_order(new_alloc_len), old_alloc_len << 1);
		newptr = realloc(*fb, new_alloc_len);
		if (!newptr)
			return -ENOMEM;
		*fb = newptr;
		/* 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	109	if (new_alloc_len > old_alloc_len) {
d0b96690 DG	110	struct lttng_filter_bytecode_alloc *newptr;
d0b96690 DG	111
ec96a8f6 MD	112	new_alloc_len =
ec96a8f6 MD	113	max_t(uint32_t, 1U << get_count_order(new_alloc_len), old_alloc_len << 1);
d0b96690 DG	114	newptr = realloc(*fb, new_alloc_len);
d0b96690 DG	115	if (!newptr)
953192ba	116	return -ENOMEM;
d0b96690	117	*fb = newptr;
1029587a	118	/* We zero directly the memory from start of allocation. */
ec96a8f6 MD	119	memset(&((char ) fb)[old_alloc_len], 0, new_alloc_len - old_alloc_len);
ec96a8f6 MD	120	(*fb)->alloc_len = new_alloc_len;
953192ba MD	121	}
	122	(*fb)->b.len += padding;
	123	ret = (*fb)->b.len;
	124	(*fb)->b.len += len;
	125	return ret;
	126	}
	127
	128	static
53a80697	129	int bytecode_push(struct lttng_filter_bytecode_alloc *fb, const void data,
953192ba MD	130	uint32_t align, uint32_t len)
	131	{
	132	int32_t offset;
	133
	134	offset = bytecode_reserve(fb, align, len);
	135	if (offset < 0)
	136	return offset;
	137	memcpy(&(*fb)->b.data[offset], data, len);
	138	return 0;
	139	}
	140
	141	static
53a80697	142	int bytecode_push_logical(struct lttng_filter_bytecode_alloc **fb,
953192ba MD	143	struct logical_op *data,
	144	uint32_t align, uint32_t len,
	145	uint16_t *skip_offset)
	146	{
	147	int32_t offset;
	148
	149	offset = bytecode_reserve(fb, align, len);
	150	if (offset < 0)
	151	return offset;
	152	memcpy(&(*fb)->b.data[offset], data, len);
	153	*skip_offset =
	154	(void ) &((struct logical_op ) &(*fb)->b.data[offset])->skip_offset
	155	- (void ) &(fb)->b.data[0];
	156	return 0;
	157	}
	158
	159	static
53a80697	160	int bytecode_patch(struct lttng_filter_bytecode_alloc **fb,
953192ba MD	161	const void *data,
	162	uint16_t offset,
	163	uint32_t len)
	164	{
	165	if (offset >= (*fb)->b.len) {
	166	return -EINVAL;
	167	}
	168	memcpy(&(*fb)->b.data[offset], data, len);
	169	return 0;
	170	}
	171
	172	static
	173	int visit_node_root(struct filter_parser_ctx ctx, struct ir_op node)
	174	{
	175	int ret;
	176	struct return_op insn;
	177
	178	/* Visit child */
	179	ret = recursive_visit_gen_bytecode(ctx, node->u.root.child);
	180	if (ret)
	181	return ret;
	182
	183	/* Generate end of bytecode instruction */
	184	insn.op = FILTER_OP_RETURN;
	185	return bytecode_push(&ctx->bytecode, &insn, 1, sizeof(insn));
	186	}
	187
953192ba MD	188	static
	189	int visit_node_load(struct filter_parser_ctx ctx, struct ir_op node)
	190	{
	191	int ret;
	192
	193	switch (node->data_type) {
	194	case IR_DATA_UNKNOWN:
	195	default:
	196	fprintf(stderr, "[error] Unknown data type in %s\n",
	197	__func__);
	198	return -EINVAL;
	199
	200	case IR_DATA_STRING:
	201	{
	202	struct load_op *insn;
	203	uint32_t insn_len = sizeof(struct load_op)
	204	+ strlen(node->u.load.u.string) + 1;
	205
	206	insn = calloc(insn_len, 1);
	207	if (!insn)
	208	return -ENOMEM;
	209	insn->op = FILTER_OP_LOAD_STRING;
953192ba MD	210	strcpy(insn->data, node->u.load.u.string);
	211	ret = bytecode_push(&ctx->bytecode, insn, 1, insn_len);
	212	free(insn);
	213	return ret;
	214	}
	215	case IR_DATA_NUMERIC:
	216	{
	217	struct load_op *insn;
	218	uint32_t insn_len = sizeof(struct load_op)
	219	+ sizeof(struct literal_numeric);
	220
	221	insn = calloc(insn_len, 1);
	222	if (!insn)
	223	return -ENOMEM;
	224	insn->op = FILTER_OP_LOAD_S64;
953192ba MD	225	(int64_t ) insn->data = node->u.load.u.num;
	226	ret = bytecode_push(&ctx->bytecode, insn, 1, insn_len);
	227	free(insn);
	228	return ret;
	229	}
e90d8561 MD	230	case IR_DATA_FLOAT:
	231	{
	232	struct load_op *insn;
	233	uint32_t insn_len = sizeof(struct load_op)
	234	+ sizeof(struct literal_double);
	235
	236	insn = calloc(insn_len, 1);
	237	if (!insn)
	238	return -ENOMEM;
	239	insn->op = FILTER_OP_LOAD_DOUBLE;
e90d8561 MD	240	(double ) insn->data = node->u.load.u.flt;
	241	ret = bytecode_push(&ctx->bytecode, insn, 1, insn_len);
	242	free(insn);
	243	return ret;
	244	}
953192ba MD	245	case IR_DATA_FIELD_REF:
	246	{
	247	struct load_op *insn;
	248	uint32_t insn_len = sizeof(struct load_op)
	249	+ sizeof(struct field_ref);
	250	struct field_ref ref_offset;
ec96a8f6 MD	251	uint32_t reloc_offset_u32;
ec96a8f6 MD	252	uint16_t reloc_offset;
953192ba MD	253
	254	insn = calloc(insn_len, 1);
	255	if (!insn)
	256	return -ENOMEM;
	257	insn->op = FILTER_OP_LOAD_FIELD_REF;
953192ba MD	258	ref_offset.offset = (uint16_t) -1U;
953192ba MD	259	memcpy(insn->data, &ref_offset, sizeof(ref_offset));
65775683	260	/* reloc_offset points to struct load_op */
ec96a8f6 MD	261	reloc_offset_u32 = bytecode_get_len(&ctx->bytecode->b);
	262	if (reloc_offset_u32 > LTTNG_FILTER_MAX_LEN - 1) {
	263	free(insn);
	264	return -EINVAL;
	265	}
	266	reloc_offset = (uint16_t) reloc_offset_u32;
953192ba MD	267	ret = bytecode_push(&ctx->bytecode, insn, 1, insn_len);
	268	if (ret) {
	269	free(insn);
	270	return ret;
	271	}
	272	/* append reloc */
	273	ret = bytecode_push(&ctx->bytecode_reloc, &reloc_offset,
	274	1, sizeof(reloc_offset));
	275	if (ret) {
	276	free(insn);
	277	return ret;
	278	}
	279	ret = bytecode_push(&ctx->bytecode_reloc, node->u.load.u.ref,
	280	1, strlen(node->u.load.u.ref) + 1);
	281	free(insn);
	282	return ret;
	283	}
	284	}
	285	}
	286
	287	static
	288	int visit_node_unary(struct filter_parser_ctx ctx, struct ir_op node)
	289	{
	290	int ret;
	291	struct unary_op insn;
	292
	293	/* Visit child */
	294	ret = recursive_visit_gen_bytecode(ctx, node->u.unary.child);
	295	if (ret)
	296	return ret;
	297
	298	/* Generate end of bytecode instruction */
	299	switch (node->u.unary.type) {
	300	case AST_UNARY_UNKNOWN:
	301	default:
	302	fprintf(stderr, "[error] Unknown unary node type in %s\n",
	303	__func__);
	304	return -EINVAL;
	305	case AST_UNARY_PLUS:
	306	/* Nothing to do. */
	307	return 0;
	308	case AST_UNARY_MINUS:
	309	insn.op = FILTER_OP_UNARY_MINUS;
953192ba MD	310	return bytecode_push(&ctx->bytecode, &insn, 1, sizeof(insn));
	311	case AST_UNARY_NOT:
	312	insn.op = FILTER_OP_UNARY_NOT;
953192ba MD	313	return bytecode_push(&ctx->bytecode, &insn, 1, sizeof(insn));
	314	}
	315	}
	316
	317	/*
	318	* Binary comparator nesting is disallowed. This allows fitting into
	319	* only 2 registers.
	320	*/
	321	static
	322	int visit_node_binary(struct filter_parser_ctx ctx, struct ir_op node)
	323	{
	324	int ret;
	325	struct binary_op insn;
	326
	327	/* Visit child */
	328	ret = recursive_visit_gen_bytecode(ctx, node->u.binary.left);
	329	if (ret)
	330	return ret;
	331	ret = recursive_visit_gen_bytecode(ctx, node->u.binary.right);
	332	if (ret)
	333	return ret;
	334
	335	switch (node->u.binary.type) {
	336	case AST_OP_UNKNOWN:
	337	default:
	338	fprintf(stderr, "[error] Unknown unary node type in %s\n",
	339	__func__);
	340	return -EINVAL;
	341
	342	case AST_OP_AND:
	343	case AST_OP_OR:
	344	fprintf(stderr, "[error] Unexpected logical node type in %s\n",
	345	__func__);
	346	return -EINVAL;
	347
	348	case AST_OP_MUL:
	349	insn.op = FILTER_OP_MUL;
	350	break;
	351	case AST_OP_DIV:
	352	insn.op = FILTER_OP_DIV;
	353	break;
	354	case AST_OP_MOD:
	355	insn.op = FILTER_OP_MOD;
	356	break;
	357	case AST_OP_PLUS:
	358	insn.op = FILTER_OP_PLUS;
	359	break;
	360	case AST_OP_MINUS:
	361	insn.op = FILTER_OP_MINUS;
	362	break;
	363	case AST_OP_RSHIFT:
	364	insn.op = FILTER_OP_RSHIFT;
	365	break;
	366	case AST_OP_LSHIFT:
	367	insn.op = FILTER_OP_LSHIFT;
	368	break;
	369	case AST_OP_BIN_AND:
	370	insn.op = FILTER_OP_BIN_AND;
	371	break;
	372	case AST_OP_BIN_OR:
	373	insn.op = FILTER_OP_BIN_OR;
	374	break;
	375	case AST_OP_BIN_XOR:
	376	insn.op = FILTER_OP_BIN_XOR;
377	break;
378
379	case AST_OP_EQ:
380	insn.op = FILTER_OP_EQ;
381	break;
382	case AST_OP_NE:
383	insn.op = FILTER_OP_NE;
384	break;
385	case AST_OP_GT:
386	insn.op = FILTER_OP_GT;
387	break;
388	case AST_OP_LT:
389	insn.op = FILTER_OP_LT;
390	break;
391	case AST_OP_GE:
392	insn.op = FILTER_OP_GE;
393	break;
394	case AST_OP_LE:
395	insn.op = FILTER_OP_LE;
396	break;
397	}
398	return bytecode_push(&ctx->bytecode, &insn, 1, sizeof(insn));
399	}
400
8cf9540a MD	401	/*
	402	* A logical op always return a s64 (1 or 0).
	403	*/
953192ba MD	404	static
	405	int visit_node_logical(struct filter_parser_ctx ctx, struct ir_op node)
	406	{
	407	int ret;
	408	struct logical_op insn;
	409	uint16_t skip_offset_loc;
	410	uint16_t target_loc;
	411
	412	/* Visit left child */
	413	ret = recursive_visit_gen_bytecode(ctx, node->u.binary.left);
	414	if (ret)
	415	return ret;
8cf9540a MD	416	/* Cast to s64 if float or field ref */
	417	if (node->u.binary.left->data_type == IR_DATA_FIELD_REF
	418	\|\| node->u.binary.left->data_type == IR_DATA_FLOAT) {
	419	struct cast_op cast_insn;
	420
29fefef8 MD	421	if (node->u.binary.left->data_type == IR_DATA_FIELD_REF) {
	422	cast_insn.op = FILTER_OP_CAST_TO_S64;
	423	} else {
	424	cast_insn.op = FILTER_OP_CAST_DOUBLE_TO_S64;
	425	}
8cf9540a MD	426	ret = bytecode_push(&ctx->bytecode, &cast_insn,
	427	1, sizeof(cast_insn));
	428	if (ret)
	429	return ret;
	430	}
953192ba MD	431	switch (node->u.logical.type) {
	432	default:
	433	fprintf(stderr, "[error] Unknown node type in %s\n",
	434	__func__);
	435	return -EINVAL;
	436
	437	case AST_OP_AND:
	438	insn.op = FILTER_OP_AND;
	439	break;
	440	case AST_OP_OR:
	441	insn.op = FILTER_OP_OR;
	442	break;
	443	}
	444	insn.skip_offset = (uint16_t) -1UL; /* Temporary */
	445	ret = bytecode_push_logical(&ctx->bytecode, &insn, 1, sizeof(insn),
	446	&skip_offset_loc);
	447	if (ret)
	448	return ret;
	449	/* Visit right child */
	450	ret = recursive_visit_gen_bytecode(ctx, node->u.binary.right);
	451	if (ret)
	452	return ret;
8cf9540a MD	453	/* Cast to s64 if float or field ref */
	454	if (node->u.binary.right->data_type == IR_DATA_FIELD_REF
	455	\|\| node->u.binary.right->data_type == IR_DATA_FLOAT) {
	456	struct cast_op cast_insn;
	457
29fefef8 MD	458	if (node->u.binary.right->data_type == IR_DATA_FIELD_REF) {
	459	cast_insn.op = FILTER_OP_CAST_TO_S64;
	460	} else {
	461	cast_insn.op = FILTER_OP_CAST_DOUBLE_TO_S64;
	462	}
8cf9540a MD	463	ret = bytecode_push(&ctx->bytecode, &cast_insn,
	464	1, sizeof(cast_insn));
	465	if (ret)
	466	return ret;
	467	}
953192ba MD	468	/* We now know where the logical op can skip. */
	469	target_loc = (uint16_t) bytecode_get_len(&ctx->bytecode->b);
	470	ret = bytecode_patch(&ctx->bytecode,
	471	&target_loc, /* Offset to jump to */
	472	skip_offset_loc, /* Where to patch */
	473	sizeof(uint16_t));
	474	return ret;
	475	}
	476
	477	/*
	478	* Postorder traversal of the tree. We need the children result before
	479	* we can evaluate the parent.
	480	*/
	481	static
	482	int recursive_visit_gen_bytecode(struct filter_parser_ctx *ctx,
	483	struct ir_op *node)
	484	{
	485	switch (node->op) {
	486	case IR_OP_UNKNOWN:
	487	default:
	488	fprintf(stderr, "[error] Unknown node type in %s\n",
	489	__func__);
	490	return -EINVAL;
	491
	492	case IR_OP_ROOT:
	493	return visit_node_root(ctx, node);
	494	case IR_OP_LOAD:
	495	return visit_node_load(ctx, node);
	496	case IR_OP_UNARY:
	497	return visit_node_unary(ctx, node);
	498	case IR_OP_BINARY:
	499	return visit_node_binary(ctx, node);
	500	case IR_OP_LOGICAL:
	501	return visit_node_logical(ctx, node);
	502	}
	503	}
	504
a187da1a	505	LTTNG_HIDDEN
953192ba MD	506	void filter_bytecode_free(struct filter_parser_ctx *ctx)
	507	{
	508	free(ctx->bytecode);
	509	ctx->bytecode = NULL;
	510	free(ctx->bytecode_reloc);
	511	ctx->bytecode_reloc = NULL;
	512	}
	513
a187da1a	514	LTTNG_HIDDEN
953192ba MD	515	int filter_visitor_bytecode_generate(struct filter_parser_ctx *ctx)
	516	{
	517	int ret;
	518
	519	ret = bytecode_init(&ctx->bytecode);
	520	if (ret)
	521	return ret;
	522	ret = bytecode_init(&ctx->bytecode_reloc);
	523	if (ret)
	524	goto error;
	525	ret = recursive_visit_gen_bytecode(ctx, ctx->ir_root);
	526	if (ret)
	527	goto error;
	528
	529	/* Finally, append symbol table to bytecode */
	530	ctx->bytecode->b.reloc_table_offset = bytecode_get_len(&ctx->bytecode->b);
	531	return bytecode_push(&ctx->bytecode, ctx->bytecode_reloc->b.data,
	532	1, bytecode_get_len(&ctx->bytecode_reloc->b));
	533
	534	error:
	535	filter_bytecode_free(ctx);
	536	return ret;
	537	}