X-Git-Url: https://thelambdalab.xyz/gitweb/index.cgi?a=blobdiff_plain;f=src%2Fforth.jl;h=134b6516753e1dab85b687fdbe21ff56361fa1bf;hb=dfc28eefbcea7eb34cf9c1e0df010322b291c40a;hp=bf2c8fedc3c1d72b1957554b1efe3cdc10d7c14d;hpb=f756abef44feaa53e5f3cf2b7ff2f9bc7940eb10;p=forth.jl.git diff --git a/src/forth.jl b/src/forth.jl index bf2c8fe..134b651 100644 --- a/src/forth.jl +++ b/src/forth.jl @@ -108,6 +108,7 @@ end # 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 @@ -116,15 +117,26 @@ 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] @@ -184,10 +196,12 @@ end 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) @@ -233,9 +247,9 @@ defConst("DOVAR", DOVAR) 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 @@ -394,14 +408,14 @@ TWODIV = defPrimWord("2/", () -> begin 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) @@ -436,12 +450,12 @@ GE = defPrimWord(">=", () -> begin 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) @@ -591,29 +605,13 @@ end) sources = Array{Any,1}() currentSource() = sources[length(sources)] -defConst("TIB", TIB) -NUMTIB, NUMTIB_CFA = defNewVar("#TIB", 0) -TOIN, TOIN_CFA = defNewVar(">IN", 0) -EOF = defConst("EOF", 4) - -KEY = defPrimWord("KEY", () -> begin - if mem[TOIN] >= mem[NUMTIB] - mem[TOIN] = 0 - - if !eof(currentSource()) - line = readline(currentSource()) - mem[NUMTIB] = length(line) - putString(line, TIB) - else - mem[NUMTIB] = 1 - mem[TIB] = EOF - end +EOF = defPrimWord("\x04", () -> begin + close(pop!(sources)) + if !isempty(sources) + return NEXT + else + return 0 end - - pushPS(mem[TIB + mem[TOIN]]) - mem[TOIN] += 1 - - return NEXT end) EMIT = defPrimWord("EMIT", () -> begin @@ -621,70 +619,31 @@ EMIT = defPrimWord("EMIT", () -> begin return NEXT end) -WORD = defPrimWord("WORD", () -> begin - - eof_char = Char(EOF) - c = eof_char - - while true - callPrim(mem[KEY]) - c = Char(popPS()) - - if c == ' ' || c == '\t' - continue - end - - break - end - - wordAddr = mem[HERE] - offset = 0 - - if c == '\n' || c == eof_char - # Treat newline as a special word - - mem[wordAddr + offset] = Int64(c) - pushPS(wordAddr) - pushPS(1) - return NEXT - end - - while true - mem[wordAddr + offset] = Int64(c) - offset += 1 - - callPrim(mem[KEY]) - c = Char(popPS()) +SPAN, SPAN_CFA = defNewVar("SPAN", 0) +EXPECT = defPrimWord("EXPECT", () -> begin + maxLen = popPS() + addr = popPS() - if c == ' ' || c == '\t' || c == '\n' || c == eof_char - # Rewind KEY - mem[TOIN] -= 1 - break - end + if !eof(currentSource()) + line = chomp(readline(currentSource())) + mem[SPAN] = min(length(line), maxLen) + putString(line[1:mem[SPAN]], addr) + else + mem[SPAN] = 1 + mem[addr] = 4 # eof end - wordLen = offset - - pushPS(wordAddr) - pushPS(wordLen) - return NEXT end) BASE, BASE_CFA = defNewVar("BASE", 10) NUMBER = defPrimWord("NUMBER", () -> begin - - wordLen = popPS() - wordAddr = popPS() + wordAddr = popPS()+1 + wordLen = mem[wordAddr-1] s = getString(wordAddr, wordLen) - try - pushPS(parse(Int64, s, mem[BASE])) - pushPS(0) - catch - pushPS(1) # Error indication - end + pushPS(parse(Int64, s, mem[BASE])) return NEXT end) @@ -693,8 +652,9 @@ end) FIND = defPrimWord("FIND", () -> begin - wordLen = popPS() - wordAddr = popPS() + countedAddr = popPS() + wordAddr = countedAddr + 1 + wordLen = mem[countedAddr] word = lowercase(getString(wordAddr, wordLen)) latest = LATEST @@ -733,7 +693,7 @@ TOCFA = defPrimWord(">CFA", () -> begin return NEXT end) -TODFA = defWord(">DFA", [TOCFA, INCR, EXIT]) +TOPFA = defWord(">PFA", [TOCFA, INCR, EXIT]) # Branching @@ -752,17 +712,34 @@ ZBRANCH = defPrimWord("0BRANCH", () -> begin return NEXT end) -# Compilation +# Strings -STATE, STATE_CFA = defNewVar("STATE", 0) +LITSTRING = defPrimWord("LITSTRING", () -> begin + len = mem[reg.IP] + reg.IP += 1 + pushPS(reg.IP) + pushPS(len) + reg.IP += len -HEADER = defPrimWord("HEADER", () -> begin + return NEXT +end) - wordLen = popPS() - wordAddr = popPS() - word = getString(wordAddr, wordLen) +TYPE = defPrimWord("TYPE", () -> begin + len = popPS() + addr = popPS() + str = getString(addr, len) + print(str) + return NEXT +end) - createHeader(word, 0) +# Outer interpreter + +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) @@ -774,161 +751,125 @@ COMMA = defPrimWord(",", () -> begin return NEXT end) -LBRAC = defPrimWord("[", () -> begin - mem[STATE] = 0 - return NEXT -end, flags=F_IMMED) - -RBRAC = defPrimWord("]", () -> begin - mem[STATE] = 1 - return NEXT -end, flags=F_IMMED) +BTICK = defWord("[']", + [FROMR, DUP, INCR, TOR, FETCH, EXIT]) -HIDDEN = defPrimWord("HIDDEN", () -> begin - addr = popPS() + 1 - mem[addr] = mem[addr] $ F_HIDDEN - return NEXT +EXECUTE = defPrimWord("EXECUTE", () -> begin + reg.W = popPS() + return mem[reg.W] end) -HIDE = defWord("HIDE", - [WORD, - FIND, - HIDDEN, - EXIT]) +TIB_CFA = defConst("TIB", TIB) +NUMTIB, NUMTIB_CFA = defNewVar("#TIB", 0) +TOIN, TOIN_CFA = defNewVar(">IN", 0) -COLON = defWord(":", - [WORD, - HEADER, - LIT, DOCOL, COMMA, - LATEST_CFA, FETCH, HIDDEN, - RBRAC, +QUERY = defWord("QUERY", + [TIB_CFA, LIT, 80, EXPECT, + SPAN_CFA, FETCH, NUMTIB_CFA, STORE, + LIT, 0, TOIN_CFA, STORE, EXIT]) -SEMICOLON = defWord(";", - [LIT, EXIT, COMMA, - LATEST_CFA, FETCH, HIDDEN, - LBRAC, - EXIT], flags=F_IMMED) +WORD = defPrimWord("WORD", () -> begin + delim = popPS() -IMMEDIATE = defPrimWord("IMMEDIATE", () -> begin - lenAndFlagsAddr = mem[LATEST] + 1 - mem[lenAndFlagsAddr] = mem[lenAndFlagsAddr] $ F_IMMED - return NEXT -end, flags=F_IMMED) + # Chew up initial occurrences of delim + while (mem[TOIN] + if (mem[addr] == delim) + break + end -CREATE = defWord("CREATE", - [WORD, - HEADER, - LIT, DOVAR, COMMA, EXIT]); + count += 1 + addr += 1 + end + + # Record count + mem[countAddr] = count + pushPS(countAddr) -DODOES = defPrim(() -> begin - pushRS(reg.IP) - reg.IP = reg.W + 1 return NEXT -end, name="DOCOL") +end) -defConst("DODOES", DODOES) +PARSE = defPrimWord("PARSE", () -> begin + delim = popPS() -FROMDOES_PAREN = defWord("(DOES>)", - [DODOES, LATEST, FETCH, TOCFA, STORE, EXIT]) + # Chew up initial occurrences of delim + addr = mem[HERE] -FROMDOES = defWord("DOES>", - [BTICK, FROMDOES_PAREN, COMMA, BTICK, EXIT, COMMA, - BTICK, LIT, COMMA, LATEST, FETCH, TODFA, COMMA], flags=F_IMMED) - + # Start reading input stream + count = 0 + while (mem[TOIN] begin - len = mem[reg.IP] - reg.IP += 1 - pushPS(reg.IP) - pushPS(len) - reg.IP += len + count += 1 + addr += 1 + end - return NEXT -end) + pushPS(addr) + pushPS(count) -TYPE = defPrimWord("TYPE", () -> begin - len = popPS() - addr = popPS() - str = getString(addr, len) - print(str) return NEXT end) -# Outer interpreter - -EXECUTE = defPrimWord("EXECUTE", () -> begin - reg.W = popPS() - return mem[reg.W] +BYE = defPrimWord("BYE", () -> begin + println("Bye!") + return 0 end) -type ParseError <: Exception - wordName::ASCIIString -end -Base.showerror(io::IO, ex::ParseError) = print(io, "Parse error at word: '$(ex.wordName)'.") - -DEBUG, DEBUG_CFA = defNewVar("DEBUG", 0) - -INTERPRET = defPrimWord("INTERPRET", () -> begin - - callPrim(mem[WORD]) - - wordName = getString(mem[reg.PSP-1], mem[reg.PSP]) - if mem[DEBUG] != 0 - println("... ", replace(replace(wordName, "\004", "EOF"), "\n", "\\n"), " ...") - end - - callPrim(mem[TWODUP]) - callPrim(mem[FIND]) +STATE, STATE_CFA = defNewVar("STATE", 0) - wordAddr = mem[reg.PSP] +INTERPRET = defWord("INTERPRET", + [LIT, 32, WORD, # Read next space-delimited word - if wordAddr>0 - # Word in dictionary + DUP, FETCH, ZE, ZBRANCH, 3, + DROP, EXIT, # Exit if TIB is exhausted - isImmediate = (mem[wordAddr+1] & F_IMMED) != 0 - callPrim(mem[TOCFA]) + STATE_CFA, FETCH, ZBRANCH, 31, + # Compiling + DUP, FIND, QDUP, ZBRANCH, 19, - callPrim(mem[NROT]) # get rid of extra copy of word string details - popPS() - popPS() + # Found word. + SWAP, DROP, + DUP, TOCFA, SWAP, INCR, FETCH, LIT, F_IMMED, AND, ZBRANCH, 4, + # Immediate: Execute! + EXECUTE, BRANCH, -33, - if mem[STATE] == 0 || isImmediate - # Execute! - return callPrim(mem[EXECUTE]) - else - # Append CFA to dictionary - callPrim(mem[COMMA]) - end - else - # Not in dictionary, assume number + # Not immediate: Compile! + COMMA, BRANCH, -36, - popPS() + # No word found, parse number + NUMBER, BTICK, LIT, COMMA, COMMA, BRANCH, -43, + + # Interpreting + DUP, FIND, QDUP, ZBRANCH, 7, - callPrim(mem[NUMBER]) + # Found word. Execute! + SWAP, DROP, TOCFA, EXECUTE, BRANCH, -54, - if popPS() != 0 - throw(ParseError(wordName)) - end + # No word found, parse number and leave on stack + NUMBER, BRANCH, -57, + EXIT] +) - if mem[STATE] == 0 - # Number already on stack! - else - # Append literal to dictionary - pushPS(LIT) - callPrim(mem[COMMA]) - callPrim(mem[COMMA]) - end +PROMPT = defPrimWord("PROMPT", () -> begin + if (mem[STATE] == 0 && currentSource() == STDIN) + println(" ok") end return NEXT @@ -936,28 +877,15 @@ end) QUIT = defWord("QUIT", [RSP0_CFA, RSPSTORE, - INTERPRET, - BRANCH,-2]) - -BYE = defPrimWord("BYE", () -> begin - return 0 -end) - -PROMPT = defPrimWord("PROMPT", () -> begin - println(" ok") -end) - -NL = defPrimWord("\n", () -> begin - if mem[STATE] == 0 && currentSource() == STDIN - callPrim(mem[PROMPT]) - end - return NEXT -end, flags=F_IMMED) + QUERY, + INTERPRET, PROMPT, + BRANCH,-4]) 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")) @@ -968,24 +896,61 @@ INCLUDE = defPrimWord("INCLUDE", () -> begin return NEXT end) -EOF_WORD = defPrimWord("\x04", () -> begin - if currentSource() != STDIN - close(currentSource()) - end +# Compilation - pop!(sources) +HEADER = defPrimWord("HEADER", () -> begin + wordAddr = popPS()+1 + wordLen = mem[wordAddr-1] + word = getString(wordAddr, wordLen) - if length(sources)>0 - if currentSource() == STDIN - callPrim(mem[PROMPT]) - end + createHeader(word, 0) - return NEXT - else - return 0 - end + return NEXT +end) + +LBRAC = defPrimWord("[", () -> begin + mem[STATE] = 0 + return NEXT +end, flags=F_IMMED) + +RBRAC = defPrimWord("]", () -> begin + mem[STATE] = 1 + return NEXT end, flags=F_IMMED) +HIDDEN = defPrimWord("HIDDEN", () -> begin + addr = popPS() + 1 + mem[addr] = mem[addr] $ F_HIDDEN + return NEXT +end) + +HIDE = defWord("HIDE", + [LIT, 32, WORD, + FIND, + HIDDEN, + EXIT]) + +COLON = defWord(":", + [LIT, 32, WORD, + HEADER, + LIT, DOCOL, COMMA, + LATEST_CFA, FETCH, HIDDEN, + RBRAC, + EXIT]) + +SEMICOLON = defWord(";", + [LIT, EXIT, COMMA, + LATEST_CFA, FETCH, HIDDEN, + LBRAC, + EXIT], flags=F_IMMED) + +IMMEDIATE = defPrimWord("IMMEDIATE", () -> begin + lenAndFlagsAddr = mem[LATEST] + 1 + mem[lenAndFlagsAddr] = mem[lenAndFlagsAddr] $ F_IMMED + return NEXT +end, flags=F_IMMED) + + #### VM loop #### initialized = false @@ -1019,10 +984,7 @@ function run(;initialize=true) 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 @@ -1033,6 +995,11 @@ function run(;initialize=true) close(pop!(sources)) end + # Want backtrace in here eventually + println("reg.W: $(reg.W) reg.IP: $(reg.IP)") + print("PS: "); printPS() + print("RS: "); printRS() + mem[STATE] = 0 mem[NUMTIB] = 0 reg.PSP = mem[PSP0]