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@@ -28,10 +28,10 @@ _start: .asciz "NIL" # dec %si ; dec %cx ; dec %sp
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kT: .asciz "T" # add %dl,(%si) boot A:\ DL=0
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start: ljmp $0x7c00>>4,$begin # cs = 0x7c00 is boot address
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.asciz "" # interned strings
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-kRead: .asciz "READ" # builtin for eval
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-kPrint: .asciz "PRINT" # builtin for eval
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kQuote: .asciz "QUOTE" # builtin for eval
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kCond: .asciz "COND" # builtin for eval
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+kRead: .asciz "READ" # builtin to apply
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+kPrint: .asciz "PRINT" # builtin to apply
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kCar: .asciz "CAR" # builtin to apply
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kCdr: .asciz "CDR" # ordering matters
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kCons: .asciz "CONS" # must be 3rd last
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@@ -54,7 +54,7 @@ begin: mov $0x8000,%sp # uses higher address as stack
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mov $2,%bx
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main: mov %sp,%cx
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mov $'\r',%al
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- call PutChar
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+ call PutChar # call first to initialize %dx
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call Read
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call Eval
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xchg %si,%ax
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@@ -94,9 +94,9 @@ GetToken: # GetToken():al, dl is g_look
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4: mov $')',%al
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jmp PutChar
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-Print: xchg %di,%si
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+Print: xchg %di,%si # Print(x:si)
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test %di,%di
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- jnz PrintObject
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+ jnz PrintObject # print newline for empty args
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mov $'\r',%al
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.PutObject: # .PutObject(c:al,x:si)
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.PrintString: # nul-terminated in si
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@@ -110,8 +110,10 @@ PrintObject: # PrintObject(x:si)
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jnz .PrintString # -> ret
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ret
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-Read: mov %bp,%dx # Get cached character
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+Read: mov %bp,%dx # get cached character
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call GetToken
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+# jmp GetObject
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+
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GetObject: # called just after GetToken
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cmp $'(',%al
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je GetList
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@@ -141,7 +143,7 @@ Intern: push %cx # Intern(cx,di): ax
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GetChar:xor %ax,%ax # GetChar→al:dl
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int $0x16 # get keystroke
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- mov %ax,%bp # Used for READ
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+ mov %ax,%bp # used for READ
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PutChar:mov $0x0e,%ah # prints CP-437
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int $0x10 # vidya service
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cmp $'\r',%al # don't clobber
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@@ -245,7 +247,7 @@ Assoc: mov %dx,%si # Assoc(x:ax,y:dx):ax
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mov (%bx,%si),%si
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scasw
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jne 1b
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- .byte 0xA9 # shifted ip; read as test, cmp
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+ .byte 0xA9 # shifted ip; reads as test, cmp
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Cadr: mov (%bx,%di),%di # contents of decrement register
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.byte 0x3C # cmp §scasw,%al (nop next byte)
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Cdr: scasw # increments our data index by 2
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@@ -297,10 +299,10 @@ Eval: test %ax,%ax # Eval(e:ax,a:dx):ax
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1: .ascii " SECTORLISP v2 "
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.word 0xAA55
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2: .type .sig,@object
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- .type kRead,@object
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- .type kPrint,@object
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.type kQuote,@object
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.type kCond,@object
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+ .type kRead,@object
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+ .type kPrint,@object
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.type kAtom,@object
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.type kCar,@object
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.type kCdr,@object
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Hikaru Ikuta