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Implementing Forth
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Previous: 'More Compiler Hacking'
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0:09Recap and set the stage for the day working on a FORTH system1
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0:09Recap and set the stage for the day working on a FORTH system1
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0:09Recap and set the stage for the day working on a FORTH system1
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2:13Point out Sean's 1992 IOCCC entry 'FIRST & THIRD almost FORTH'2 and others
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2:13Point out Sean's 1992 IOCCC entry 'FIRST & THIRD almost FORTH'2 and others
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2:13Point out Sean's 1992 IOCCC entry 'FIRST & THIRD almost FORTH'2 and others
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10:17Point out Lennart Augustsson's 1996 IOCCC entry 'august'3
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10:17Point out Lennart Augustsson's 1996 IOCCC entry 'august'3
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10:17Point out Lennart Augustsson's 1996 IOCCC entry 'august'3
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12:55Point out JONESFORTH4 with a little comparison with Sean's 'FIRST & THIRD almost FORTH'5
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12:55Point out JONESFORTH4 with a little comparison with Sean's 'FIRST & THIRD almost FORTH'5
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12:55Point out JONESFORTH4 with a little comparison with Sean's 'FIRST & THIRD almost FORTH'5
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18:24Review the addition of if in the assembler
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18:24Review the addition of if in the assembler
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18:24Review the addition of if in the assembler
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20:02Set up to implement our FORTH system, creating forth.asm, forth_test() and assemble_file()
20:02Set up to implement our FORTH system, creating forth.asm, forth_test() and assemble_file()
20:02Set up to implement our FORTH system, creating forth.asm, forth_test() and assemble_file()
34:57Run it to see that it looks good
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34:57Run it to see that it looks good
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34:57Run it to see that it looks good
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35:18FORTH, as a stack-oriented language
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35:18FORTH, as a stack-oriented language
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35:18FORTH, as a stack-oriented language
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37:32Introduce cmd_reg() to support register aliasing
37:32Introduce cmd_reg() to support register aliasing
37:32Introduce cmd_reg() to support register aliasing
39:54Test our new .reg instruction
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39:54Test our new .reg instruction
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39:54Test our new .reg instruction
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40:34Set up FORTH register roles: sp (stack pointer), pc (program counter) and rsp (return stack pointer)
40:34Set up FORTH register roles: sp (stack pointer), pc (program counter) and rsp (return stack pointer)
40:34Set up FORTH register roles: sp (stack pointer), pc (program counter) and rsp (return stack pointer)
43:28Indirect threading-style FORTH, like JONESFORTH6
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43:28Indirect threading-style FORTH, like JONESFORTH6
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43:28Indirect threading-style FORTH, like JONESFORTH6
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47:16Create an add routine, initially in direct threading style
47:16Create an add routine, initially in direct threading style
47:16Create an add routine, initially in direct threading style
53:30Set aside space for the stack
53:30Set aside space for the stack
53:30Set aside space for the stack
56:57Rename add to do_add and introduce do_push to push values onto the stack
56:57Rename add to do_add and introduce do_push to push values onto the stack
56:57Rename add to do_add and introduce do_push to push values onto the stack
1:00:51Enable cmd_uint32() to support variable initialisation from labels
1:00:51Enable cmd_uint32() to support variable initialisation from labels
1:00:51Enable cmd_uint32() to support variable initialisation from labels
1:02:53Run it to find that it assembled, but unexpectedly subtracts 8 from t1
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1:02:53Run it to find that it assembled, but unexpectedly subtracts 8 from t1
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1:02:53Run it to find that it assembled, but unexpectedly subtracts 8 from t1
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1:05:16Consider what may be wrong with cmd_la()
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1:05:16Consider what may be wrong with cmd_la()
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1:05:16Consider what may be wrong with cmd_la()
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1:07:19Run it and talk through the program execution
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1:07:19Run it and talk through the program execution
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1:07:19Run it and talk through the program execution
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1:08:34Step through cmd_la() and inspect the asm
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1:08:34Step through cmd_la() and inspect the asm
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1:08:34Step through cmd_la() and inspect the asm
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1:12:07Test loading into t1 from the program_start label
1:12:07Test loading into t1 from the program_start label
1:12:07Test loading into t1 from the program_start label
1:12:29Run it to find that this works, and it is loading correctly after all, only the disassembler doesn't account for the offset
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1:12:29Run it to find that this works, and it is loading correctly after all, only the disassembler doesn't account for the offset
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1:12:29Run it to find that this works, and it is loading correctly after all, only the disassembler doesn't account for the offset
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1:14:02Run our entire FORTH system
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1:14:02Run our entire FORTH system
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1:14:02Run our entire FORTH system
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1:16:06Create a do_print routine
1:16:06Create a do_print routine
1:16:06Create a do_print routine
1:18:12Run it to see our printout
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1:18:12Run it to see our printout
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1:18:12Run it to see our printout
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1:18:59Rename do_print to do_emit and enable it to print a newline and subtract '0' from the ASCII value
1:18:59Rename do_print to do_emit and enable it to print a newline and subtract '0' from the ASCII value
1:18:59Rename do_print to do_emit and enable it to print a newline and subtract '0' from the ASCII value
1:20:34Run it to see ILLEGAL instructions
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1:20:34Run it to see ILLEGAL instructions
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1:20:34Run it to see ILLEGAL instructions
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1:21:35Call do_push after do_add instructions
1:21:35Call do_push after do_add instructions
1:21:35Call do_push after do_add instructions
1:22:19Run it to look for our printout
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1:22:19Run it to look for our printout
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1:22:19Run it to look for our printout
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1:22:58Fix our program to + '0'
1:22:58Fix our program to + '0'
1:22:58Fix our program to + '0'
1:23:04Run it to see our 3
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1:23:04Run it to see our 3
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1:23:04Run it to see our 3
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1:23:38Enable cmd_loop() to toggle "quiet" running on a key press
1:23:38Enable cmd_loop() to toggle "quiet" running on a key press
1:23:38Enable cmd_loop() to toggle "quiet" running on a key press
1:24:49Rename do_emit to do_putchar and create a do_getchar routine
1:24:49Rename do_emit to do_putchar and create a do_getchar routine
1:24:49Rename do_emit to do_putchar and create a do_getchar routine
1:25:39Run it to see our 3
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1:25:39Run it to see our 3
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1:25:39Run it to see our 3
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1:25:47Enable our program to add user-input values
1:25:47Enable our program to add user-input values
1:25:47Enable our program to add user-input values
1:26:53Run it to see that it doesn't work
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1:26:53Run it to see that it doesn't work
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1:26:53Run it to see that it doesn't work
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1:27:05Fix our input handling
1:27:05Fix our input handling
1:27:05Fix our input handling
1:28:15Step through our program to see how it handles our input
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1:28:15Step through our program to see how it handles our input
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1:28:15Step through our program to see how it handles our input
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1:30:29Fix our program to do_add the final '0'
1:30:29Fix our program to do_add the final '0'
1:30:29Fix our program to do_add the final '0'
1:30:49Run it to see that it's correct
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1:30:49Run it to see that it's correct
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1:30:49Run it to see that it's correct
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1:31:09Direct and indirect threading
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1:31:09Direct and indirect threading
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1:31:09Direct and indirect threading
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1:34:05That's all we have time for today
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1:34:05That's all we have time for today
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1:34:05That's all we have time for today
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Next: 'Forth Implementation, Part 2'
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