PPT-Assemblers

Two functions Mnemonic opcode Machine Code Symbolic labels machine addresses in memory Some features Depend on assembly language and machine language as well may be very subtle. specified by programmer into binary Typically assemblers make two passes over the assembly file First pass reads each line and records labels in a symbol table Second pass use info in symbol table to produce actual machine code for each line brPage specified by programmer into binary Typically assemblers make two passes over the assembly file First pass reads each line and records labels in a symbol table Second pass use info in symbol table to produce actual machine code for each line brPage Chapter 6 (. Section 6.4 - Optional). Chapter 9 (Section 9.2). Chapter 10 (Section 10.1). Chapter 11 (Sections 11.1, 11.2) . Layered Systems. Tempus and Hora. 1000 parts in a watch. Tempus and Hora. Hora. System Software. by . Leland L. Beck. Chapter 2. Chap 2. Role of Assembler. Source. Program. Assembler. Object. Code. Loader. Executable . Code. Linker. Chap 2. Chapter 2 -- Outline. Basic Assembler Functions. School of Engineering. Assembler. Reference. Abyss 1.5.1. Simpson et al., J. T., Wong, K., Jackman, S. D., Schein, J. E., Jones,. . S. J., and . Birol. , I. (2009). Abyss: a parallel assembler for. . . S. trictly linear nature forces assemblers to introduce errors:. These simple events are difficult to represented in the FASTA format. . The assembler is forced to choose, resulting in a loss of information and errors.. Esha. Jain, . VivekSagar. KR, Benjamin Metcalf, . Raghav. Sharma, Charles . Wigington. , Juliette . Zerick. Genome Assembly. Outline. Input Data. Sequence read data. Pipeline Review. U. n-processed data. Hakim Weatherspoon. CS 3410, . Spring 2012. Computer Science. Cornell University. See P&H Appendix . B. .1-2, . and Chapters 2.8 and 2.12; . als. 2.16 and 2.17 . Write-. Back. Memory. Instruction. See: P&H . Appendix B.3-4 and 2.12. Hakim . Weatherspoon. CS 3410, Spring 2012. Computer Science. Cornell University. Goal for Today: Putting it all Together. Review Calling Convention. Compiler . See: P&H Appendix B.3-4. Hakim . Weatherspoon. CS 3410, Spring . 2012. Computer Science. Cornell University. Administrivia. Upcoming agenda. HW3 . due . today. . Tuesday, March 13. th. HW4 available by tomorrow, Wednesday March 14. School of Engineering. Assembler. Reference. Abyss 1.5.1. Simpson et al., J. T., Wong, K., Jackman, S. D., Schein, J. E., Jones,. . S. J., and . Birol. , I. (2009). Abyss: a parallel assembler for. . Assemblers, Linkers, and Loaders [Weatherspoon, Bala , Bracy , and Sirer ] Hakim Weatherspoon CS 3410 Computer Science Cornell University addi x5 , x0 , 10 muli x5 , x5 , 2 addi x5 , x5 Examples. .... T: ADDI r4, r0, -1. BEQ r3, r0, B. ADDI r4, r4, 1. LW r3, 0(r3). J T. NOP. B: .... .... JAL L. nop. nop. L: LW r5, 0(r31). ADDI r5, r5, 1. SW r5, 0(r31). .... cs3410 Recap. Mnemonic . opcode. Machine. Code. Symbolic labels  machine addresses (in memory). Some features:. Depend on assembly language . and machine language as well, may be very subtle.. Other features:.