You will implement, using C, pass 1 of an assembler for the machine architecture described in the SIC System Programmer’s guide provided as reference for this course. Your project will accept 1 command-line argument, which is a file that contains a SIC assembler program. Project 1 will create and output a symbol table as a result of analyzing the input SIC assembly file.
Remember that to generate SIC object code, we will need to make two passes through the assembly file. Pass one generates the symbol table and pass two uses the symbol table and op codes to generate the object file. You will be doing pass two via project 2. Think about this in your design.
There are some validation checks which should be done during pass one. You should carefully consider the errors in the SIC assembly file input that can and should be discovered during pass one and when encountered in the source file, generate an appropriate error message and stop the assembly process. There are AT LEAST FOUR errors which pass one should be able to detect and report (all of which should HALT the assembly process and generate an error message).
For example: if an error is found with the input assembly file, you should stop the process of creating the symbol table and output the following:
ASSEMBLY ERROR:
<The contents of the source line of assembly which contains the error><CrLf>
Line <line #> <Description of Error Encountered><CrLf>
If the SIC assembly file is valid, then project 1 should output, its symbol table. For each symbol, there should be one line of output: the symbol name followed by a <tab> character, followed by the hexadecimal address of the symbol, followed by a <CrLf>.
—- Example input —-
COPY START 1000 FIRST STL RETADR CLOOP JSUB RDREC LDA LENGTH COMP ZERO JEQ ENDFIL JSUB WRREC J CLOOP ENDFIL LDA EOF STA BUFFER LDA THREE STA LENGTH JSUB WRREC LDL RETADR RSUB EOF BYTE C'EOF' THREE WORD 3 ZERO WORD 0 RETADR RESW 1 LENGTH RESW 1 BUFFER RESB 4096 RDREC LDX ZERO LDA ZERO RLOOP TD INPUT JEQ RLOOP RD INPUT COMP ZERO JEQ EXIT STCH BUFFER,X TIX MAXLEN JLT RLOOP EXIT STX LENGTH RSUB INPUT BYTE X'F1' MAXLEN WORD 4096 WRREC LDX ZERO WLOOP TD OUTPUT JEQ WLOOP LDCH BUFFER,X WD OUTPUT TIX LENGTH JLT WLOOP RSUB OUTPUT BYTE X'05' END FIRST
The correct output for this input file would be:
COPY 1000
FIRST 1000
CLOOP 1003
ENDFIL 1015
EOF 102A
THREE 102D
ZERO 1030
RETADR 1033
LENGTH 1036
BUFFER 1039
RDREC 2039
RLOOP 203F
EXIT 2057
INPUT 205D
MAXLEN 205E
WRREC 2061
WLOOP 2064
OUTPUT 2079
You will then implement, using C, pass 2 of an assembler for the machine architecture described in the SIC System Programmer’s guide provided as reference for this course. Your project will accept 1 command-line argument, which is a file that contains a SIC assembler program. Project 2 will create and output an object file in the format described in the SIC Object File Format document.
Remember that to generate SIC object code, we will need to make two passes through the assembly file. Pass one generated the symbol table and pass two uses the symbol table and op codes to generate the object file.
There are some validation checks which should be done during pass two (checks which really cannot be done during pass one). You should carefully consider the errors in the SIC assembly file input that can and should be discovered during pass two and when encountered in the source file, generate an appropriate error message and stop the assembly process. There are errors which pass two should be able to detect and report (all of which should HALT the assembly process and generate an error message).
For example: if an error is found with the input assembly file, you should stop the process of creating the symbol table and output the following:
ASSEMBLY ERROR:
<The contents of the source line of assembly which contains the error><CrLf>
Line <line #> <Description of Error Encountered><CrLf>
If the SIC assembly file is valid, then project 2 should write the appropriate object file
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