1. A transmission system for an air conditioner, comprising:
a plurality of air conditioning units each including an outdoor unit and a plurality of indoor units, the outdoor unit and the plurality of indoor units being connected to each other through an internalexternal transmission line for data transmission; and
an integrated transmission line connecting a centralized control unit and the plurality of air conditioning units to each other for data transmission, the centralized control unit providing centralized control on the plurality of air conditioning units, wherein
each internalexternal transmission line and the integrated transmission line are connected to the outdoor unit, and are connected to each other by a transmission relay provided in the outdoor unit for separating data transmission between the internalexternal transmission line and the integrated transmission line,
the transmission relay includes: a switching hub for daisy-chain connecting the plurality of air conditioning units through the integrated transmission line; and a gateway connected to the switching hub and the internalexternal transmission line, the gateway separately controlling data transmission on the internalexternal transmission line and data transmission on the integrated transmission line,
the outdoor units of the plurality of air condition units are sequentially connected to each other by the transmission relay provided in each of the outdoor units to sequentially transmit data between the outdoor units through the respective transmission relays,
the switching hub includes a first port connecting to the gateway, a second port connecting to the integrated transmission line, and a third port connecting to the integrated transmission line or being opened, and
the gateway is connected to a control board of each of the outdoor units.
2. The transmission system of claim 1,
wherein the switching hub is a three-port switching hub for connecting the plurality of air conditioning units through the integrated transmission line to have a spanning tree.
3. The transmission system of claim 1,
wherein the transmission relay includes an insulation transformer for common mode noise reduction.
4. The transmission system of claim 1,
wherein the integrated transmission line is formed of a transmission wire including a mis-wiring protection connector.
5. The transmission system of claim 1,
wherein the integrated transmission line is composed of a CSMACD LAN.
6. The transmission system of claim 1,
wherein the outdoor unit includes the transmission relay.
7. The transmission system of claim 1,
wherein the integrated transmission line connects to the gateway via the switching hub and the each internalexternal transmission line connects to the gateway without passing through the switching hub.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A method for compiling optimization of an application, comprising:
determining could-be-constant variables in source code of the application, the could-be-constant variables each having a uniquely determined constant value during run time, wherein the determining comprises:
analyzing the source code to obtain potential could-be-constant variables;
removing the potential could-be-constant variables that are assigned multiple times from the potential could-be-constant variables by counting assignment operations of the potential could-be-constant variables and removing the potential could-be-constant of which the count of the assignment operations exceeds one, resulting in a list of remaining potential could-be-constant variables;
determining affected variables that are affected by external information variables in the source code, the external information variables comprising information received from outside of the application; and
selecting matching variables from the remaining potential could-be-constant variables and the affected variables as the could-be-constant variables;
obtaining constant variables designated as final constant variables and values of the constant variables using the could-be-constant variables; and
compiling the application using the constant variables and the values of the constant variables.
2. The method according to claim 1, wherein the analyzing of the source code to obtain potential could-be-constant variables comprises:
searching the source code for a branch selection statement; and
extracting variables in the branch select statement as the potential could-be-constant variables.
3. The method according to claim 1, wherein the analyzing of the source code to obtain potential could-be-constant variables comprises:
searching the source code for a branch selection statement;
based on determining that there is no function call in the branch selection statement, extracting variables in the branch selection statement as the potential could-be-constant variables; and
based on determining that there is a function call in the branch selection statement and the called function is a function with definite semantics, extracting variables in the branch selection statement as the potential could-be-constant variables.
4. The method according to claim 1, wherein the determining of affected variables affected by external information variables in the source code comprises:
searching the source code for command line arguments or environment variables describing the application’s run environment or parameter variables in an external configuration file of the application as the external information variables;
searching for variables that are assigned directly by the external information variables, as directly affected variables; and
searching for variables that are assigned as constants through constant propagation when the directly affected variables are considered as constants, as indirectly affected variables;
wherein the affected variables include the directly affected variables and the indirectly affected variables.
5. The method according to claim 1, wherein the obtaining of the constant variables designated as final constant variables and values of the constant variables using the could-be-constant variables comprises:
presenting the could-be-constant variables; and
accepting the designation of the constant variables and values of the constant variables in the could-be-constant variables.
6. The method according to claim 1, wherein the obtaining of the constant variables designated as final constant variables and values of the constant variables using the could-be-constant variables comprises:
reading an external configuration file describing the variables to be constant and their values; and
determining the could-be-constant variables that are identical with the variables in the external configuration file in the could-be-constant variables as the constant variables.
7. A system for compiling optimization of an application, the system comprising:
a processor operable to execute a plurality of instructions; and
a system memory that stores the instructions to implement a compiler upon execution by the processor, the compiler comprising:
a could-be-constant variable determination means configured to determine could-be-constant variables in source code of the application, the could-be-constant variables each having a uniquely determined constant value during run time, wherein the could-be-constant variable determination means comprises:
an analysis module configured to analyze the source code to obtain potential could-be-constant variables;
a removing module configured to remove the potential could-be-constant variables that are assigned multiple times from the potential could-be-constant variables by counting assignment operations of the potential could-be-constant variables and removing the potential could-be-constant of which the count of the assignment operations exceeds one, resulting in a list of remaining potential could-be-constant variables;
a determination module configured to determine affected variables that are affected by external information variables in the source code, the external information variables comprising information received from outside of the application; and
a selection module to select matching variables from the remaining potential could-be-constant variables and the affected variables as the could-be-constant variables;
a constant variable obtaining means configured to obtain constant variables designated as final constant variables and values of the constant variables using the could-be-constant variables; and
a compiling means configured to compile the application using the constant variables and the values of the constant variables.
8. The system according to claim 7, wherein the analysis module comprises:
a searching unit configured to search the source code for a branch selection statement; and
an extracting unit configured to extract variables in the branch select statement as the potential could-be-constant variables.
9. The system according to claim 7, wherein the analysis module comprises:
a searching unit configured to search the source code for a branch selection statement; and
an extracting unit configured to extract, if there is no function call in the branch selection statement, variables in the branch selection statement as the potential could-be-constant variables, and to extract, if there is a function call in the branch selection statement and the called function is a function with definite semantics, variables in the branch selection statement as the potential could-be-constant variables.
10. The system according to claim 7, wherein the determination module comprises:
a first searching unit configured to search the source code for command line arguments or environment variables describing the application’s run environment or parameter variables in an external configuration file of the application as the external information variables; and
a second searching unit configured to search for variables that are assigned directly by the external information variables, as directly affected variables, and to search for variables that are assigned as constants through constant propagation when the directly affected variables are considered as constants, as indirectly affected variables;
wherein the affected variables include the directly affected variables and the indirectly affected variables.
11. The system according to claim 7, wherein the constant variable obtaining means comprises:
a presenting module configured to present the could-be-constant variables; and
an accepting module configured to accept the designation of the constant variables and the values of the constant variables in the could-be-constant variables.
12. The system according to claim 7, wherein the constant variable obtaining means comprises:
a reading module configured to read an external configuration file describing variables to be constant and their values; and
a constant variable determination module configured to determine the could-be-constant variables that are identical with the variables in the external configuration file in the could-be-constant variables as the constant variables.
13. A computer program product for compiling optimization of an application, the computer program product comprising a non-transitory computer readable storage medium having program code embodied therewith, the program code executable by a computer processor for:
determining could-be-constant variables in source code of the application, the could-be-constant variables each having a uniquely determined constant value during run time, wherein the determining comprises:
analyzing the source code to obtain potential could-be-constant variables;
removing the potential could-be-constant variables that are assigned multiple times from the potential could-be-constant variables by counting assignment operations of the potential could-be-constant variables and removing the potential could-be-constant of which the count of the assignment operations exceeds one, resulting in a list of remaining potential could-be-constant variables;
determining affected variables that are affected by external information variables in the source code, the external information variables comprising information received from outside of the application; and
selecting matching variables from the remaining potential could-be-constant variables and the affected variables as the could-be-constant variables;
obtaining constant variables designated as final constant variables and values of the constant variables using the could-be-constant variables; and
compiling the application using the constant variables and the values of the constant variables.
14. The computer program product of claim 13, wherein the analyzing of the source code to obtain potential could-be-constant variables comprises:
searching the source code for a branch selection statement; and
extracting variables in the branch select statement as the potential could-be-constant variables.
15. The computer program product of claim 13, wherein the analyzing of the source code to obtain potential could-be-constant variables comprises:
searching the source code for a branch selection statement;
based on determining that there is no function call in the branch selection statement, extracting variables in the branch selection statement as the potential could-be-constant variables; and
based on determining that there is a function call in the branch selection statement and the called function is a function with definite semantics, extracting variables in the branch selection statement as the potential could-be-constant variables.
16. The computer program product of claim 13, wherein the determining of affected variables affected by external information variables in the source code comprises:
searching the source code for command line arguments or environment variables describing the application’s run environment or parameter variables in an external configuration file of the application as the external information variables;
searching for variables that are assigned directly by the external information variables, as directly affected variables; and
searching for variables that are assigned as constants through constant propagation when the directly affected variables are considered as constants, as indirectly affected variables;
wherein the affected variables include the directly affected variables and the indirectly affected variables.
17. The computer program product of claim 13, wherein the obtaining of the constant variables designated as final constant variables and values of the constant variables using the could-be-constant variables comprises:
presenting the could-be-constant variables; and
accepting the designation of the constant variables and values of the constant variables in the could-be-constant variables.
18. The computer program product of claim 13, wherein the obtaining of the constant variables designated as final constant variables and values of the constant variables using the could-be-constant variables comprises:
reading an external configuration file describing the variables to be constant and their values; and
determining the could-be-constant variables that are identical with the variables in the external configuration file in the could-be-constant variables as the constant variables.