# Built-in variables
nextVarAddr = 1
-H = nextVarAddr; nextVarAddr += 1
-LATEST = nextVarAddr; nextVarAddr += 1
+H = nextVarAddr; nextVarAddr += 1 # Next free memory address
+FORTH_LATEST = nextVarAddr; nextVarAddr += 1 # LFA of latest word in system dict
+CURRENT = nextVarAddr; nextVarAddr += 1 # Current compilation dict
RSP0 = nextVarAddr # bottom of RS
PSP0 = RSP0 + size_RS # bottom of PS
TIB = PSP0 + size_PS # address of terminal input buffer
-mem[H] = TIB + size_TIB # location of bottom of dictionary
-mem[LATEST] = 0 # no previous definition
+mem[H] = TIB + size_TIB # location of bottom of dictionary
+mem[FORTH_LATEST] = 0 # no previous definition
+mem[CURRENT] = FORTH_LATEST # Compile words to system dict initially
DICT = mem[H] # Save bottom of dictionary as constant
F_HIDDEN = 64
NFA_MARK = 128
+function dictWrite(ints::Array{Int64,1})
+ mem[mem[H]:(mem[H]+length(ints)-1)] = ints
+ mem[H] += length(ints)
+end
+dictWrite(int::Int64) = dictWrite([int])
+dictWriteString(string::ASCIIString) = dictWrite([Int64(c) for c in string])
+
function createHeader(name::AbstractString, flags::Int64)
- mem[mem[H]] = mem[LATEST]
- mem[LATEST] = mem[H]
+ mem[mem[H]] = mem[mem[CURRENT]]
+ mem[mem[CURRENT]] = mem[H]
mem[H] += 1
- mem[mem[H]] = length(name) | flags | NFA_MARK; mem[H] += 1
- putString(name, mem[H]); mem[H] += length(name)
+ dictWrite(length(name) | flags | NFA_MARK)
+ dictWriteString(name)
end
function defPrimWord(name::AbstractString, f::Function; flags::Int64=0)
createHeader(name, flags)
codeWordAddr = mem[H]
- mem[codeWordAddr] = defPrim(f, name=name)
- mem[H] += 1
+ dictWrite(defPrim(f, name=name))
return codeWordAddr
end
createHeader(name, flags)
addr = mem[H]
- mem[mem[H]] = DOCOL
- mem[H] += 1
+ dictWrite(DOCOL)
- for wordAddr in wordAddrs
- mem[mem[H]] = wordAddr
- mem[H] += 1
- end
+ dictWrite(wordAddrs)
return addr
end
end)))
end
-function defNewVar(name::AbstractString, initial::Int64; flags::Int64=0)
+function defNewVar(name::AbstractString, initial::Array{Int64,1}; flags::Int64=0)
createHeader(name, flags)
codeWordAddr = mem[H]
varAddr = mem[H] + 1
- mem[mem[H]] = DOVAR; mem[H] += 1
- mem[mem[H]] = initial; mem[H] += 1
+ dictWrite(DOVAR)
+ dictWrite(initial)
return varAddr, codeWordAddr
end
+defNewVar(name::AbstractString, initial::Int64; flags::Int64=0) =
+ defNewVar(name, [initial]; flags=flags)
+
function defConst(name::AbstractString, val::Int64; flags::Int64=0)
createHeader(name, flags)
codeWordAddr = mem[H]
- mem[mem[H]] = DOCON; mem[H] += 1
- mem[mem[H]] = val; mem[H] += 1
+ dictWrite(DOCON)
+ dictWrite(val)
return codeWordAddr
end
# Dictionary entries for core built-in variables, constants
H_CFA = defExistingVar("H", H)
-LATEST_CFA = defExistingVar("LATEST", LATEST)
+CURRENT_CFA = defExistingVar("CURRENT", CURRENT)
PSP0_CFA = defConst("PSP0", PSP0)
RSP0_CFA = defConst("RSP0", RSP0)
# Dictionary searches
-TOCFA_CFA = defPrimWord(">CFA", () -> begin
+FROMLINK_CFA = defPrimWord("LINK>", () -> begin
addr = popPS()
lenAndFlags = mem[addr+1]
return NEXT
end)
-TOBODY_CFA = defWord(">BODY", [INCR_CFA, EXIT_CFA])
+createHeader("FORTH", 0)
+FORTH_CFA = mem[H]
+dictWrite(defPrim(() -> begin
+ mem[CONTEXT] = reg.W
+ return NEXT
+end, name="FORTH"))
+dictWrite(FORTH_LATEST)
+
+CONTEXT, CONTEXT_CFA = defNewVar("CONTEXT", zeros(Int64, 100))
+mem[CONTEXT] = FORTH_CFA
+NUMCONTEXT, NUMCONTEXT_CFA = defNewVar("#CONTEXT", 1)
FIND_CFA = defPrimWord("FIND", () -> begin
wordLen = mem[countedAddr]
word = lowercase(getString(wordAddr, wordLen))
- latest = LATEST
+ context = mem[CONTEXT:(CONTEXT+mem[NUMCONTEXT]-1)]
+
lenAndFlags = 0
-
- i = 0
- while (latest = mem[latest]) > 0
- lenAndFlags = mem[latest+1]
- len = lenAndFlags & F_LENMASK
- hidden = (lenAndFlags & F_HIDDEN) == F_HIDDEN
-
- if hidden || len != wordLen
- continue
+ lfa = 0
+
+ for vocabCFA in reverse(context)
+ lfa = mem[vocabCFA+1]
+
+ while (lfa = mem[lfa]) > 0
+
+ lenAndFlags = mem[lfa+1]
+ len = lenAndFlags & F_LENMASK
+ hidden = (lenAndFlags & F_HIDDEN) == F_HIDDEN
+
+ if hidden || len != wordLen
+ continue
+ end
+
+ thisWord = lowercase(getString(lfa+2, len))
+
+ if thisWord == word
+ break
+ end
end
-
- thisAddr = latest+2
- thisWord = lowercase(getString(thisAddr, len))
- if lowercase(thisWord) == lowercase(word)
+ if lfa>0
break
end
end
- if latest > 0
- pushPS(latest)
- callPrim(mem[TOCFA_CFA])
+ if lfa > 0
+ pushPS(lfa)
+ callPrim(mem[FROMLINK_CFA])
if (lenAndFlags & F_IMMED) == F_IMMED
pushPS(1)
else
return NEXT
end)
-# Outer interpreter
-
-COMMA_CFA = defPrimWord(",", () -> begin
- mem[mem[H]] = popPS()
- mem[H] += 1
-
- return NEXT
-end)
-
-BTICK_CFA = defWord("[']",
- [FROMR_CFA, DUP_CFA, INCR_CFA, TOR_CFA, FETCH_CFA, EXIT_CFA])
-
-EXECUTE_CFA = defPrimWord("EXECUTE", () -> begin
- reg.W = popPS()
- return mem[reg.W]
-end)
+# Interpreter/Compiler-specific I/O
TIB_CFA = defConst("TIB", TIB)
NUMTIB, NUMTIB_CFA = defNewVar("#TIB", 0)
return NEXT
end)
-PARSE_CFA = defPrimWord("PARSE", () -> begin
- delim = popPS()
-
- # Chew up initial occurrences of delim
- addr = mem[H]
-
- # 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_CFA = defPrimWord("BYE", () -> begin
- println("\nBye!")
- return 0
-end)
+# Compilation
STATE, STATE_CFA = defNewVar("STATE", 0)
-INTERPRET_CFA = defWord("INTERPRET",
- [LIT_CFA, 32, WORD_CFA, # Read next space-delimited word
-
- DUP_CFA, FETCH_CFA, ZE_CFA, ZBRANCH_CFA, 3,
- DROP_CFA, EXIT_CFA, # Exit if TIB is exhausted
-
- STATE_CFA, FETCH_CFA, ZBRANCH_CFA, 24,
- # Compiling
- FIND_CFA, QDUP_CFA, ZBRANCH_CFA, 13,
-
- # Found word.
- LIT_CFA, -1, EQ_CFA, INVERT_CFA, ZBRANCH_CFA, 4,
-
- # Immediate: Execute!
- EXECUTE_CFA, BRANCH_CFA, -26,
-
- # Not immediate: Compile!
- COMMA_CFA, BRANCH_CFA, -29,
-
- # No word found, parse number
- NUMBER_CFA, BTICK_CFA, LIT_CFA, COMMA_CFA, COMMA_CFA, BRANCH_CFA, -36,
-
- # Interpreting
- FIND_CFA, QDUP_CFA, ZBRANCH_CFA, 5,
-
- # Found word. Execute!
- DROP_CFA, EXECUTE_CFA, BRANCH_CFA, -44,
-
- # No word found, parse number and leave on stack
- NUMBER_CFA, BRANCH_CFA, -47,
- EXIT_CFA])
-
-PROMPT_CFA = defPrimWord("PROMPT", () -> begin
- if (mem[STATE] == 0 && currentSource() == STDIN)
- println(" ok")
- end
-
- return NEXT
-end)
-
-QUIT_CFA = defWord("QUIT",
- [LIT_CFA, 0, STATE_CFA, STORE_CFA,
- LIT_CFA, 0, NUMTIB_CFA, STORE_CFA,
- RSP0_CFA, RSPSTORE_CFA,
- QUERY_CFA,
- INTERPRET_CFA, PROMPT_CFA,
- BRANCH_CFA,-4])
-
-ABORT_CFA = defWord("ABORT",
- [PSP0_CFA, PSPSTORE_CFA, QUIT_CFA])
-
-INCLUDE_CFA = defPrimWord("INCLUDE", () -> begin
- pushPS(32)
- callPrim(mem[WORD_CFA])
- wordAddr = popPS()+1
- wordLen = mem[wordAddr-1]
- word = getString(wordAddr, wordLen)
-
- push!(sources, open(word, "r"))
-
- # Clear input buffer
- mem[NUMTIB] = 0
+COMMA_CFA = defPrimWord(",", () -> begin
+ mem[mem[H]] = popPS()
+ mem[H] += 1
return NEXT
end)
-# Compilation
-
HERE_CFA = defWord("HERE",
[H_CFA, FETCH_CFA, EXIT_CFA])
DOES_HELPER_CFA = defPrimWord("(DOES>)", () -> begin
- pushPS(mem[LATEST])
- callPrim(mem[TOCFA_CFA])
+ pushPS(mem[mem[CURRENT]])
+ callPrim(mem[FROMLINK_CFA])
cfa = popPS()
runtimeAddr = popPS()
end)), name="doesPrim")
return NEXT
-end, flags=F_IMMED)
+end, flags=F_IMMED | F_HIDDEN)
DOES_CFA = defWord("DOES>",
- [BTICK_CFA, LIT_CFA, COMMA_CFA, HERE_CFA, LIT_CFA, 3, ADD_CFA, COMMA_CFA,
- BTICK_CFA, DOES_HELPER_CFA, COMMA_CFA, BTICK_CFA, EXIT_CFA, COMMA_CFA, EXIT_CFA],
+ [LIT_CFA, LIT_CFA, COMMA_CFA, HERE_CFA, LIT_CFA, 3, ADD_CFA, COMMA_CFA,
+ LIT_CFA, DOES_HELPER_CFA, COMMA_CFA, LIT_CFA, EXIT_CFA, COMMA_CFA, EXIT_CFA],
flags=F_IMMED)
LBRAC_CFA = defPrimWord("[", () -> begin
end, flags=F_IMMED)
HIDDEN_CFA = defPrimWord("HIDDEN", () -> begin
- lenAndFlagsAddr = mem[LATEST] + 1
+ lenAndFlagsAddr = mem[mem[CURRENT]] + 1
mem[lenAndFlagsAddr] = mem[lenAndFlagsAddr] $ F_HIDDEN
return NEXT
end)
EXIT_CFA], flags=F_IMMED)
IMMEDIATE_CFA = defPrimWord("IMMEDIATE", () -> begin
- lenAndFlagsAddr = mem[LATEST] + 1
+ lenAndFlagsAddr = mem[mem[CURRENT]] + 1
mem[lenAndFlagsAddr] = mem[lenAndFlagsAddr] $ F_IMMED
return NEXT
end, flags=F_IMMED)
+# Outer Interpreter
+
+EXECUTE_CFA = defPrimWord("EXECUTE", () -> begin
+ reg.W = popPS()
+ return mem[reg.W]
+end)
+
+INTERPRET_CFA = defWord("INTERPRET",
+ [LIT_CFA, 32, WORD_CFA, # Read next space-delimited word
+
+ DUP_CFA, FETCH_CFA, ZE_CFA, ZBRANCH_CFA, 3,
+ DROP_CFA, EXIT_CFA, # Exit if TIB is exhausted
+
+ STATE_CFA, FETCH_CFA, ZBRANCH_CFA, 24,
+ # Compiling
+ FIND_CFA, QDUP_CFA, ZBRANCH_CFA, 13,
+
+ # Found word.
+ LIT_CFA, -1, EQ_CFA, INVERT_CFA, ZBRANCH_CFA, 4,
+
+ # Immediate: Execute!
+ EXECUTE_CFA, BRANCH_CFA, -26,
+
+ # Not immediate: Compile!
+ COMMA_CFA, BRANCH_CFA, -29,
+
+ # No word found, parse number
+ NUMBER_CFA, LIT_CFA, LIT_CFA, COMMA_CFA, COMMA_CFA, BRANCH_CFA, -36,
+
+ # Interpreting
+ FIND_CFA, QDUP_CFA, ZBRANCH_CFA, 5,
+
+ # Found word. Execute!
+ DROP_CFA, EXECUTE_CFA, BRANCH_CFA, -44,
+
+ # No word found, parse number and leave on stack
+ NUMBER_CFA, BRANCH_CFA, -47,
+ EXIT_CFA])
+
+PROMPT_CFA = defPrimWord("PROMPT", () -> begin
+ if (mem[STATE] == 0 && currentSource() == STDIN)
+ println(" ok")
+ end
+
+ return NEXT
+end)
+
+QUIT_CFA = defWord("QUIT",
+ [LIT_CFA, 0, STATE_CFA, STORE_CFA,
+ LIT_CFA, 0, NUMTIB_CFA, STORE_CFA,
+ RSP0_CFA, RSPSTORE_CFA,
+ QUERY_CFA,
+ INTERPRET_CFA, PROMPT_CFA,
+ BRANCH_CFA,-4])
+
+ABORT_CFA = defWord("ABORT",
+ [PSP0_CFA, PSPSTORE_CFA, QUIT_CFA])
+
+BYE_CFA = defPrimWord("BYE", () -> begin
+ println("\nBye!")
+ return 0
+end)
+
+# File I/O
+
+INCLUDE_CFA = defPrimWord("INCLUDE", () -> begin
+ pushPS(32)
+ callPrim(mem[WORD_CFA])
+ wordAddr = popPS()+1
+ wordLen = mem[wordAddr-1]
+ word = getString(wordAddr, wordLen)
+
+ fname = word
+ if !isfile(fname)
+ fname = Pkg.dir("forth","src",word)
+ if !isfile(fname)
+ error("No file named $word found in current directory or package source directory.")
+ end
+ end
+ push!(sources, open(fname, "r"))
+
+ # Clear input buffer
+ mem[NUMTIB] = 0
+
+ return NEXT
+end)
+
#### VM loop ####
initFileName = nothing
if isfile("lib.4th")
initFileName = "lib.4th"
-elseif isfile(Pkg.dir("forth/src/lib.4th"))
- initFileName = Pkg.dir("forth/src/lib.4th")
+elseif isfile(Pkg.dir("forth","src", "lib.4th"))
+ initFileName = Pkg.dir("forth","src","lib.4th")
end
function run(;initialize=true)
The Lambda Lab / projects / forth.jl.git / blobdiff