From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Date: Mon, 16 Jul 2012 21:56:59 +0000 (-0400)
Subject: Filter bytecode: Implement stack-based interpreter
X-Git-Tag: v2.1.0-rc1~84
X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=commitdiff_plain;h=c96b4c01d5b0dabfa5413f9ca9130c9f31b36be6

Filter bytecode: Implement stack-based interpreter

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
---

diff --git a/src/lib/lttng-ctl/filter-bytecode.h b/src/lib/lttng-ctl/filter-bytecode.h
index 1bb00dd45..df1b34c34 100644
--- a/src/lib/lttng-ctl/filter-bytecode.h
+++ b/src/lib/lttng-ctl/filter-bytecode.h
@@ -29,12 +29,6 @@
  * offsets are absolute from start of bytecode.
  */
 
-enum filter_register {
-	REG_R0 = 0,
-	REG_R1 = 1,
-	REG_ERROR,
-};
-
 struct field_ref {
 	/* Initially, symbol offset. After link, field offset. */
 	uint16_t offset;
@@ -139,7 +133,6 @@ typedef uint8_t filter_opcode_t;
 
 struct load_op {
 	filter_opcode_t op;
-	uint8_t reg;		/* enum filter_register */
 	char data[0];
 	/* data to load. Size known by enum filter_opcode and null-term char. */
 } __attribute__((packed));
@@ -150,7 +143,6 @@ struct binary_op {
 
 struct unary_op {
 	filter_opcode_t op;
-	uint8_t reg;		/* enum filter_register */
 } __attribute__((packed));
 
 /* skip_offset is absolute from start of bytecode */
@@ -161,7 +153,6 @@ struct logical_op {
 
 struct cast_op {
 	filter_opcode_t op;
-	uint8_t reg;		/* enum filter_register */
 } __attribute__((packed));
 
 struct return_op {
diff --git a/src/lib/lttng-ctl/filter-visitor-generate-bytecode.c b/src/lib/lttng-ctl/filter-visitor-generate-bytecode.c
index a9e741cd2..9877a86f9 100644
--- a/src/lib/lttng-ctl/filter-visitor-generate-bytecode.c
+++ b/src/lib/lttng-ctl/filter-visitor-generate-bytecode.c
@@ -136,22 +136,6 @@ int visit_node_root(struct filter_parser_ctx *ctx, struct ir_op *node)
 	return bytecode_push(&ctx->bytecode, &insn, 1, sizeof(insn));
 }
 
-static
-enum filter_register reg_sel(struct ir_op *node)
-{
-	switch (node->side) {
-	case IR_SIDE_UNKNOWN:
-	default:
-		fprintf(stderr, "[error] Unknown node side in %s\n",
-			__func__);
-		return REG_ERROR;
-	case IR_LEFT:
-		return REG_R0;
-	case IR_RIGHT:
-		return REG_R1;
-	}
-}
-
 static
 int visit_node_load(struct filter_parser_ctx *ctx, struct ir_op *node)
 {
@@ -174,9 +158,6 @@ int visit_node_load(struct filter_parser_ctx *ctx, struct ir_op *node)
 		if (!insn)
 			return -ENOMEM;
 		insn->op = FILTER_OP_LOAD_STRING;
-		insn->reg = reg_sel(node);
-		if (insn->reg == REG_ERROR)
-			return -EINVAL;
 		strcpy(insn->data, node->u.load.u.string);
 		ret = bytecode_push(&ctx->bytecode, insn, 1, insn_len);
 		free(insn);
@@ -192,9 +173,6 @@ int visit_node_load(struct filter_parser_ctx *ctx, struct ir_op *node)
 		if (!insn)
 			return -ENOMEM;
 		insn->op = FILTER_OP_LOAD_S64;
-		insn->reg = reg_sel(node);
-		if (insn->reg == REG_ERROR)
-			return -EINVAL;
 		*(int64_t *) insn->data = node->u.load.u.num;
 		ret = bytecode_push(&ctx->bytecode, insn, 1, insn_len);
 		free(insn);
@@ -210,9 +188,6 @@ int visit_node_load(struct filter_parser_ctx *ctx, struct ir_op *node)
 		if (!insn)
 			return -ENOMEM;
 		insn->op = FILTER_OP_LOAD_DOUBLE;
-		insn->reg = reg_sel(node);
-		if (insn->reg == REG_ERROR)
-			return -EINVAL;
 		*(double *) insn->data = node->u.load.u.flt;
 		ret = bytecode_push(&ctx->bytecode, insn, 1, insn_len);
 		free(insn);
@@ -230,11 +205,8 @@ int visit_node_load(struct filter_parser_ctx *ctx, struct ir_op *node)
 		if (!insn)
 			return -ENOMEM;
 		insn->op = FILTER_OP_LOAD_FIELD_REF;
-		insn->reg = reg_sel(node);
 		ref_offset.offset = (uint16_t) -1U;
 		memcpy(insn->data, &ref_offset, sizeof(ref_offset));
-		if (insn->reg == REG_ERROR)
-			return -EINVAL;
 		/* reloc_offset points to struct load_op */
 		reloc_offset = bytecode_get_len(&ctx->bytecode->b);
 		ret = bytecode_push(&ctx->bytecode, insn, 1, insn_len);
@@ -280,15 +252,9 @@ int visit_node_unary(struct filter_parser_ctx *ctx, struct ir_op *node)
 		return 0;
 	case AST_UNARY_MINUS:
 		insn.op = FILTER_OP_UNARY_MINUS;
-		insn.reg = reg_sel(node);
-		if (insn.reg == REG_ERROR)
-			return -EINVAL;
 		return bytecode_push(&ctx->bytecode, &insn, 1, sizeof(insn));
 	case AST_UNARY_NOT:
 		insn.op = FILTER_OP_UNARY_NOT;
-		insn.reg = reg_sel(node);
-		if (insn.reg == REG_ERROR)
-			return -EINVAL;
 		return bytecode_push(&ctx->bytecode, &insn, 1, sizeof(insn));
 	}
 }
@@ -402,7 +368,6 @@ int visit_node_logical(struct filter_parser_ctx *ctx, struct ir_op *node)
 		} else {
 			cast_insn.op = FILTER_OP_CAST_DOUBLE_TO_S64;
 		}
-		cast_insn.reg = REG_R0;
 		ret = bytecode_push(&ctx->bytecode, &cast_insn,
 					1, sizeof(cast_insn));
 		if (ret)
@@ -440,7 +405,6 @@ int visit_node_logical(struct filter_parser_ctx *ctx, struct ir_op *node)
 		} else {
 			cast_insn.op = FILTER_OP_CAST_DOUBLE_TO_S64;
 		}
-		cast_insn.reg = REG_R0;
 		ret = bytecode_push(&ctx->bytecode, &cast_insn,
 					1, sizeof(cast_insn));
 		if (ret)