# Built-in variables
nextVarAddr = 1
-RSP0 = nextVarAddr; nextVarAddr += 1
-PSP0 = nextVarAddr; nextVarAddr += 1
HERE = nextVarAddr; nextVarAddr += 1
LATEST = nextVarAddr; nextVarAddr += 1
-mem[RSP0] = nextVarAddr # bottom of RS
-mem[PSP0] = mem[RSP0] + size_RS # bottom of PS
-TIB = mem[PSP0] + size_PS # address of terminal input buffer
-mem[HERE] = TIB + size_TIB # location of bottom of dictionary
-mem[LATEST] = 0 # no previous definition
+RSP0 = nextVarAddr # bottom of RS
+PSP0 = RSP0 + size_RS # bottom of PS
+TIB = PSP0 + size_PS # address of terminal input buffer
+mem[HERE] = TIB + size_TIB # location of bottom of dictionary
+mem[LATEST] = 0 # no previous definition
DICT = mem[HERE] # Save bottom of dictionary as constant
IP::Int64 # Instruction pointer
W::Int64 # Working register
end
-reg = Reg(mem[RSP0], mem[PSP0], 0, 0)
+reg = Reg(RSP0, PSP0, 0, 0)
# Stack manipulation functions
Base.showerror(io::IO, ex::ParamStackUnderflow) = print(io, "Parameter stack underflow.")
Base.showerror(io::IO, ex::ReturnStackUnderflow) = print(io, "Return stack underflow.")
-getRSDepth() = reg.RSP - mem[RSP0]
-getPSDepth() = reg.PSP - mem[PSP0]
+getRSDepth() = reg.RSP - RSP0
+getPSDepth() = reg.PSP - PSP0
function ensurePSDepth(depth::Int64)
if getPSDepth()<depth
# Handy functions for adding/retrieving strings to/from memory.
getString(addr::Int64, len::Int64) = ASCIIString([Char(c) for c in mem[addr:(addr+len-1)]])
+
function putString(str::ASCIIString, addr::Int64)
mem[addr:(addr+length(str)-1)] = [Int64(c) for c in str]
end
function defPrim(f::Function; name="nameless")
push!(primitives, f)
- push!(primNames, replace(replace(name, "\004", "EOF"), "\n", "\\n"))
+ push!(primNames, replace(name, "\004", "EOF"))
return -length(primitives)
end
-callPrim(addr::Int64) = primitives[-addr]()
+function callPrim(addr::Int64)
+ if addr >=0 || -addr>length(primitives)
+ error("Attempted to execute non-existent primitive at address $addr.")
+ else
+ primitives[-addr]()
+ end
+end
+getPrimName(addr::Int64) = primNames[-addr]
# Word creation functions
+F_IMMED = 128
+F_HIDDEN = 256
+F_LENMASK = 127
+
function createHeader(name::AbstractString, flags::Int64)
mem[mem[HERE]] = mem[LATEST]
mem[LATEST] = mem[HERE]
function defConst(name::AbstractString, val::Int64; flags::Int64=0)
createHeader(name, flags)
+ codeWordAddr = mem[HERE]
+
mem[mem[HERE]] = DOCON; mem[HERE] += 1
mem[mem[HERE]] = val; mem[HERE] += 1
- return val
+ return codeWordAddr
end
# Threading Primitives (inner interpreter)
HERE_CFA = defExistingVar("HERE", HERE)
LATEST_CFA = defExistingVar("LATEST", LATEST)
-PSP0_CFA = defExistingVar("PSP0", PSP0)
-RSP0_CFA = defExistingVar("RSP0", RSP0)
+
+PSP0_CFA = defConst("PSP0", PSP0)
+RSP0_CFA = defConst("RSP0", RSP0)
defConst("DOCOL", DOCOL)
defConst("DOCON", DOCON)
defConst("DICT", DICT)
defConst("MEMSIZE", size_mem)
-F_IMMED = defConst("F_IMMED", 128)
-F_HIDDEN = defConst("F_HIDDEN", 256)
-F_LENMASK = defConst("F_LENMASK", 127)
+F_IMMED_CFA = defConst("F_IMMED", F_IMMED)
+F_HIDDEN_CFA = defConst("F_HIDDEN", F_HIDDEN)
+F_LENMASK_CFA = defConst("F_LENMASK", F_LENMASK)
# Basic forth primitives
return NEXT
end)
-EQU = defPrimWord("=", () -> begin
+EQ = defPrimWord("=", () -> begin
b = popPS()
a = popPS()
pushPS(a==b ? -1 : 0)
return NEXT
end)
-NEQU = defPrimWord("<>", () -> begin
+NE = defPrimWord("<>", () -> begin
b = popPS()
a = popPS()
pushPS(a!=b ? -1 : 0)
return NEXT
end)
-ZEQU = defPrimWord("0=", () -> begin
+ZE = defPrimWord("0=", () -> begin
pushPS(popPS() == 0 ? -1 : 0)
return NEXT
end)
-ZNEQU = defPrimWord("0<>", () -> begin
+ZNE = defPrimWord("0<>", () -> begin
pushPS(popPS() != 0 ? -1 : 0)
return NEXT
end)
end)
RSPSTORE = defPrimWord("RSP!", () -> begin
- RSP = popPS()
+ reg.RSP = popPS()
return NEXT
end)
end)
PSPSTORE = defPrimWord("PSP!", () -> begin
- PSP = popPS()
+ reg.PSP = popPS()
return NEXT
end)
sources = Array{Any,1}()
currentSource() = sources[length(sources)]
-EOF = defConst("EOF", 4)
+EOF = defPrimWord("\x04", () -> begin
+ close(pop!(sources))
+ if !isempty(sources)
+ return NEXT
+ else
+ return 0
+ end
+end)
EMIT = defPrimWord("EMIT", () -> begin
print(Char(popPS()))
addr = popPS()
if !eof(currentSource())
- line = readline(currentSource())
- mem[SPAN] = max(length(line), maxLen)
+ line = chomp(readline(currentSource()))
+ mem[SPAN] = min(length(line), maxLen)
putString(line[1:mem[SPAN]], addr)
else
mem[SPAN] = 1
- mem[addr] = EOF
+ mem[addr] = 4 # eof
end
return NEXT
BASE, BASE_CFA = defNewVar("BASE", 10)
NUMBER = defPrimWord("NUMBER", () -> begin
-
wordAddr = popPS()+1
wordLen = mem[wordAddr-1]
return NEXT
end)
-TODFA = defWord(">DFA", [TOCFA, INCR, EXIT])
+TOPFA = defWord(">PFA", [TOCFA, INCR, EXIT])
# Branching
# Outer interpreter
-defConst("TIB", TIB)
+TRACE = defPrimWord("TRACE", () -> begin
+ println("reg.W: $(reg.W) reg.IP: $(reg.IP)")
+ print("PS: "); printPS()
+ print("RS: "); printRS()
+ print("[paused]")
+ readline()
+
+ return NEXT
+end)
+
+COMMA = defPrimWord(",", () -> begin
+ mem[mem[HERE]] = popPS()
+ mem[HERE] += 1
+
+ return NEXT
+end)
+
+BTICK = defWord("[']",
+ [FROMR, DUP, INCR, TOR, FETCH, EXIT])
+
+EXECUTE = defPrimWord("EXECUTE", () -> begin
+ reg.W = popPS()
+ return mem[reg.W]
+end)
+
+TIB_CFA = defConst("TIB", TIB)
NUMTIB, NUMTIB_CFA = defNewVar("#TIB", 0)
TOIN, TOIN_CFA = defNewVar(">IN", 0)
QUERY = defWord("QUERY",
- [LIT, TIB, LIT, 80, EXPECT,
- LIT, SPAN, FETCH, NUMTIB, STORE,
- LIT, 0, TOIN, STORE,
+ [TIB_CFA, LIT, 160, EXPECT,
+ SPAN_CFA, FETCH, NUMTIB_CFA, STORE,
+ LIT, 0, TOIN_CFA, STORE,
EXIT])
-EXECUTE = defPrimWord("EXECUTE", () -> begin
- reg.W = popPS()
- return mem[reg.W]
+WORD = defPrimWord("WORD", () -> begin
+ delim = popPS()
+
+ # Chew up initial occurrences of delim
+ while (mem[TOIN]<mem[NUMTIB] && mem[TIB+mem[TOIN]] == delim)
+ mem[TOIN] += 1
+ end
+
+ countAddr = mem[HERE]
+ addr = mem[HERE]+1
+
+ # Start reading in word
+ count = 0
+ while (mem[TOIN]<mem[NUMTIB])
+ mem[addr] = mem[TIB+mem[TOIN]]
+ mem[TOIN] += 1
+
+ if (mem[addr] == delim)
+ break
+ end
+
+ count += 1
+ addr += 1
+ end
+
+ # Record count
+ mem[countAddr] = count
+ pushPS(countAddr)
+
+ return NEXT
+end)
+
+PARSE = defPrimWord("PARSE", () -> begin
+ delim = popPS()
+
+ # Chew up initial occurrences of delim
+ addr = mem[HERE]
+
+ # Start reading input stream
+ count = 0
+ while (mem[TOIN]<mem[NUMTIB])
+ mem[addr] = mem[TIB+mem[TOIN]]
+ mem[TOIN] += 1
+
+ if (mem[addr] == delim)
+ break
+ end
+
+ count += 1
+ addr += 1
+ end
+
+ pushPS(addr)
+ pushPS(count)
+
+ return NEXT
+end)
+
+BYE = defPrimWord("BYE", () -> begin
+ println("Bye!")
+ return 0
end)
STATE, STATE_CFA = defNewVar("STATE", 0)
INTERPRET = defWord("INTERPRET",
[LIT, 32, WORD, # Read next space-delimited word
- DUP, FETCH, ZEQ, ZBRANCH, 3,
+ DUP, FETCH, ZE, ZBRANCH, 3,
DROP, EXIT, # Exit if TIB is exhausted
-
- STATE_CFA, FETCH, ZBRANCH, 26,
+
+ STATE_CFA, FETCH, ZBRANCH, 31,
# Compiling
- DUP, FIND, ZBRANCH, 17,
+ DUP, FIND, QDUP, ZBRANCH, 19,
# Found word.
+ SWAP, DROP,
DUP, TOCFA, SWAP, INCR, FETCH, LIT, F_IMMED, AND, ZBRANCH, 4,
# Immediate: Execute!
- EXECUTE, BRANCH, -30,
+ EXECUTE, BRANCH, -33,
# Not immediate: Compile!
- COMMA, BRANCH, -33,
+ COMMA, BRANCH, -36,
# No word found, parse number
- NUMBER, BTICK, LIT, COMMA, BRANCH, -39,
+ NUMBER, BTICK, LIT, COMMA, COMMA, BRANCH, -43,
# Interpreting
- DUP, FIND, ZBRANCH, 5,
+ DUP, FIND, QDUP, ZBRANCH, 7,
# Found word. Execute!
- TOCFA, EXECUTE, BRANCH, -47,
+ SWAP, DROP, TOCFA, EXECUTE, BRANCH, -54,
# No word found, parse number and leave on stack
- NUMBER, BRANCH, -50,
+ NUMBER, BRANCH, -57,
EXIT]
)
PROMPT = defPrimWord("PROMPT", () -> begin
- if (mem[STATE] == 0 and currentSource() == STDIN)
+ if (mem[STATE] == 0 && currentSource() == STDIN)
println(" ok")
end
+
+ return NEXT
end)
QUIT = defWord("QUIT",
- [RSP0_CFA, RSPSTORE,
+ [LIT, 0, STATE_CFA, STORE,
+ LIT, 0, NUMTIB_CFA, STORE,
+ RSP0_CFA, RSPSTORE,
QUERY,
- INTERPRET, PROMPT
- BRANCH,-3])
+ INTERPRET, PROMPT,
+ BRANCH,-4])
-BYE = defPrimWord("BYE", () -> begin
- return 0
-end)
+ABORT = defWord("ABORT",
+ [PSP0_CFA, PSPSTORE, QUIT])
INCLUDE = defPrimWord("INCLUDE", () -> begin
+ pushPS(32)
callPrim(mem[WORD])
- wordLen = popPS()
- wordAddr = popPS()
+ wordAddr = popPS()+1
+ wordLen = mem[wordAddr-1]
word = getString(wordAddr, wordLen)
push!(sources, open(word, "r"))
# Compilation
HEADER = defPrimWord("HEADER", () -> begin
-
wordAddr = popPS()+1
wordLen = mem[wordAddr-1]
word = getString(wordAddr, wordLen)
return NEXT
end)
-COMMA = defPrimWord(",", () -> begin
- mem[mem[HERE]] = popPS()
- mem[HERE] += 1
-
- return NEXT
-end)
-
LBRAC = defPrimWord("[", () -> begin
mem[STATE] = 0
return NEXT
end)
HIDE = defWord("HIDE",
- [WORD,
+ [LIT, 32, WORD,
FIND,
HIDDEN,
EXIT])
COLON = defWord(":",
- [WORD,
+ [LIT, 32, WORD,
HEADER,
LIT, DOCOL, COMMA,
LATEST_CFA, FETCH, HIDDEN,
return NEXT
end, flags=F_IMMED)
-TICK = defWord("'",
- [WORD, FIND, TOCFA, EXIT])
-
-BTICK = defWord("[']",
- [FROMR, DUP, INCR, TOR, FETCH, EXIT])
-
-# CREATE and DOES>
-
-CREATE = defWord("CREATE",
- [WORD,
- HEADER,
- LIT, DOVAR, COMMA, EXIT]);
-
-DODOES = defPrim(() -> begin
- pushRS(reg.IP)
- reg.IP = reg.W + 1
- return NEXT
-end, name="DOCOL")
-
-defConst("DODOES", DODOES)
-
-FROMDOES_PAREN = defWord("(DOES>)",
- [DODOES, LATEST, FETCH, TOCFA, STORE, EXIT])
-
-FROMDOES = defWord("DOES>",
- [BTICK, FROMDOES_PAREN, COMMA, BTICK, EXIT, COMMA,
- BTICK, LIT, COMMA, LATEST, FETCH, TODFA, COMMA], flags=F_IMMED)
-
-
#### VM loop ####
initFileName = Pkg.dir("forth/src/lib.4th")
end
-function run(;initialize=false)
+function run(;initialize=true)
# Begin with STDIN as source
push!(sources, STDIN)
jmp = NEXT
while jmp != 0
try
- if mem[DEBUG] != 0
- println("Evaluating prim ", jmp," ", primNames[-jmp])
- end
-
+ #println("Entering prim $(getPrimName(jmp))")
jmp = callPrim(jmp)
catch ex
close(pop!(sources))
end
- mem[STATE] = 0
- mem[NUMTIB] = 0
- reg.PSP = mem[PSP0]
- reg.RSP = mem[RSP0]
- reg.IP = QUIT + 1
+ # QUIT
+ reg.IP = ABORT + 1
jmp = NEXT
end
end
end
function printPS()
- count = reg.PSP - mem[PSP0]
+ count = reg.PSP - PSP0
if count > 0
print("<$count>")
- for i in (mem[PSP0]+1):reg.PSP
+ for i in (PSP0+1):reg.PSP
print(" $(mem[i])")
end
println()
end
function printRS()
- count = reg.RSP - mem[RSP0]
+ count = reg.RSP - RSP0
if count > 0
print("<$count>")
- for i in (mem[RSP0]+1):reg.RSP
+ for i in (RSP0+1):reg.RSP
print(" $(mem[i])")
end
println()
The Lambda Lab / projects / forth.jl.git / blobdiff