A-6 Appendix A Assemblers,Linkers,and the SPIM Simulator addiu $29.$29.-32 $31,20($29) Sw $4, 32($29) $5. 36($29) SW $0. 24($29) $0 28($29) $14,28($29) 1w $24,24($29) multu $14.$14 addiu $8, $14,1 slti $1, $8.101 SW $8, 28($29) mflo $15 addu $25,$24,$15 bne $1, $0.-9 SW $25.24($29) lui $4. 4096 1w $5. 24($29) jal 1048812 addiu $4, $4,1072 lw $31,20($29) addiu $29. $29,32 jr $31 move $2, $0 FIGURE A.1.3 The same routine written in assembly language.However,the code for the rou- tine does not label registers or memory locations nor include comments. high-level language (such as C or Pascal)into an equivalent program in machine source language The high- or assembly language.The high-level language is called the source language,and level language in which a pro- the compiler's output is its target language. gram is originally written. Assembly language's other role is as a language in which to write programs. This role used to be the dominant one.Today,however,because of larger main memories and better compilers,most programmers write in a high-level language and rarely,if ever,see the instructions that a computer executes.Nevertheless, assembly language is still important to write programs in which speed or size are critical or to exploit hardware features that have no analogues in high-level lan- guages. Although this appendix focuses on MIPS assembly language,assembly pro- gramming on most other machines is very similar.The additional instructions and address modes in CISC machines,such as the VAX,can make assembly pro- grams shorter but do not change the process of assembling a program or provide assembly language with the advantages of high-level languages such as type- checking and structured control flow.A-6 Appendix A Assemblers, Linkers, and the SPIM Simulator high-level language (such as C or Pascal) into an equivalent program in machine or assembly language. The high-level language is called the source language, and the compiler’s output is its target language. Assembly language’s other role is as a language in which to write programs. This role used to be the dominant one. Today, however, because of larger main memories and better compilers, most programmers write in a high-level language and rarely, if ever, see the instructions that a computer executes. Nevertheless, assembly language is still important to write programs in which speed or size are critical or to exploit hardware features that have no analogues in high-level lan￾guages. Although this appendix focuses on MIPS assembly language, assembly pro￾gramming on most other machines is very similar. The additional instructions and address modes in CISC machines, such as the VAX, can make assembly pro￾grams shorter but do not change the process of assembling a program or provide assembly language with the advantages of high-level languages such as type￾checking and structured control flow. addiu $29, $29, -32 sw $31, 20($29) sw $4, 32($29) sw $5, 36($29) sw $0, 24($29) sw $0, 28($29) lw $14, 28($29) lw $24, 24($29) multu $14, $14 addiu $8, $14, 1 slti $1, $8, 101 sw $8, 28($29) mflo $15 addu $25, $24, $15 bne $1, $0, -9 sw $25, 24($29) lui $4, 4096 lw $5, 24($29) jal 1048812 addiu $4, $4, 1072 lw $31, 20($29) addiu $29, $29, 32 jr $31 move $2, $0 FIGURE A.1.3 The same routine written in assembly language. However, the code for the rou￾tine does not label registers or memory locations nor include comments. source language The high￾level language in which a pro￾gram is originally written