X-Git-Url: https://thelambdalab.xyz/gitweb/index.cgi?a=blobdiff_plain;f=src%2Fforth.jl;h=b1d782ce1d11a0e6d291083315532922ea43c51c;hb=d2b2b3e5b33f882c18c9e7cf8c6623f4e863c2dd;hp=0b4871f89c2674359f32259e35ede298614cba5f;hpb=5328ad90af9699b87b0beee70aa7a7ee6a98e8a9;p=forth.jl.git

diff --git a/src/forth.jl b/src/forth.jl
index 0b4871f..b1d782c 100644
--- a/src/forth.jl
+++ b/src/forth.jl
@@ -1,12 +1,12 @@
 module forth
 
 # VM mem size
-size_mem = 640*1024
+size_mem = 1000000 # 1 mega-int
 
 # Buffer sizes
-size_RS = 1024   # Return stack size
-size_PS = 1024   # Parameter stack size
-size_TIB = 1096  # Terminal input buffer size
+size_RS = 1000   # Return stack size
+size_PS = 1000   # Parameter stack size
+size_TIB = 1000  # Terminal input buffer size
 
 # The mem array constitutes the memory of the VM. It has the following geography:
 #
@@ -123,7 +123,7 @@ end
 
 callPrim(addr::Int64) = primitives[-addr]()
 
-# Word creation
+# Word creation functions
 
 function createHeader(name::AbstractString, flags::Int64)
     mem[mem[HERE]] = mem[LATEST]
@@ -159,7 +159,7 @@ function defWord(name::AbstractString, wordAddrs::Array{Int64,1}; flags::Int64=0
     return addr
 end
 
-# Variable creation
+# Variable creation functions
 
 function defExistingVar(name::AbstractString, varAddr::Int64; flags::Int64=0)
 
@@ -175,22 +175,17 @@ function defNewVar(name::AbstractString, initial::Int64; flags::Int64=0)
     codeWordAddr = mem[HERE]
     varAddr = mem[HERE] + 1
 
-    f = eval(:(() -> begin
-        pushPS($(varAddr))
-        return NEXT
-    end))
-
-    mem[mem[HERE]] = defPrim(f, name=name); mem[HERE] += 1
+    mem[mem[HERE]] = DOVAR; mem[HERE] += 1
     mem[mem[HERE]] = initial; mem[HERE] += 1
 
     return varAddr, codeWordAddr
 end
 
 function defConst(name::AbstractString, val::Int64; flags::Int64=0)
-    defPrimWord(name, eval(:(() -> begin
-        pushPS($(val))
-        return NEXT
-    end)))
+    createHeader(name, flags)
+
+    mem[mem[HERE]] = DOCON; mem[HERE] += 1
+    mem[mem[HERE]] = val; mem[HERE] += 1
 
     return val
 end
@@ -209,11 +204,39 @@ DOCOL = defPrim(() -> begin
     return NEXT
 end, name="DOCOL")
 
+DOVAR = defPrim(() -> begin
+    pushPS(reg.W + 1)
+    return NEXT
+end, name="DOVAR")
+
+DOCON = defPrim(() -> begin
+    pushPS(mem[reg.W + 1])
+    return NEXT
+end, name="DOVAR")
+
 EXIT = defPrimWord("EXIT", () -> begin
     reg.IP = popRS()
     return NEXT
 end)
 
+# Dictionary entries for core built-in variables, constants
+
+HERE_CFA = defExistingVar("HERE", HERE)
+LATEST_CFA = defExistingVar("LATEST", LATEST)
+PSP0_CFA = defExistingVar("PSP0", PSP0)
+RSP0_CFA = defExistingVar("RSP0", RSP0)
+
+defConst("DOCOL", DOCOL)
+defConst("DOCON", DOCON)
+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)
+
 # Basic forth primitives
 
 DROP = defPrimWord("DROP", () -> begin
@@ -241,7 +264,7 @@ OVER = defPrimWord("OVER", () -> begin
     return NEXT
 end)
 
-NROT = defPrimWord("-ROT", () -> begin
+ROT = defPrimWord("ROT", () -> begin
     a = popPS()
     b = popPS()
     c = popPS()
@@ -251,7 +274,7 @@ NROT = defPrimWord("-ROT", () -> begin
     return NEXT
 end)
 
-ROT = defPrimWord("ROT", () -> begin
+NROT = defPrimWord("-ROT", () -> begin
     a = popPS()
     b = popPS()
     c = popPS()
@@ -284,8 +307,17 @@ TWOSWAP = defPrimWord("2SWAP", () -> begin
     d = popPS()
     pushPS(b)
     pushPS(a)
-    pushPS(c)
     pushPS(d)
+    pushPS(c)
+    return NEXT
+end)
+
+TWOOVER = defPrimWord("2OVER", () -> begin
+    ensurePSDepth(4)
+    a = mem[reg.PSP-3]
+    b = mem[reg.PSP-2]
+    pushPS(a)
+    pushPS(b)
     return NEXT
 end)
 
@@ -498,24 +530,6 @@ SUBSTORE = defPrimWord("-!", () -> begin
 end)
 
 
-# Built-in variables
-
-HERE_CFA = defExistingVar("HERE", HERE)
-LATEST_CFA = defExistingVar("LATEST", LATEST)
-PSP0_CFA = defExistingVar("PSP0", PSP0)
-RSP0_CFA = defExistingVar("RSP0", RSP0)
-STATE, STATE_CFA = defNewVar("STATE", 0)
-BASE, BASE_CFA = defNewVar("BASE", 10)
-
-# Constants
-
-defConst("VERSION", 1)
-defConst("DOCOL", DOCOL)
-defConst("DICT", DICT)
-F_IMMED = defConst("F_IMMED", 128)
-F_HIDDEN = defConst("F_HIDDEN", 256)
-F_LENMASK = defConst("F_LENMASK", 127)
-
 # Return Stack
 
 TOR = defPrimWord(">R", () -> begin
@@ -612,24 +626,10 @@ WORD = defPrimWord("WORD", () -> begin
     eof_char = Char(EOF)
     c = eof_char
 
-    skip_to_end = false
     while true
-
         callPrim(mem[KEY])
         c = Char(popPS())
 
-        if c == '\\'
-            skip_to_end = true
-            continue
-        end
-
-        if skip_to_end
-            if c == '\n' || c == eof_char
-                skip_to_end = false
-            end
-            continue
-        end
-
         if c == ' ' || c == '\t'
             continue
         end
@@ -671,6 +671,7 @@ WORD = defPrimWord("WORD", () -> begin
     return NEXT
 end)
 
+BASE, BASE_CFA = defNewVar("BASE", 10)
 NUMBER = defPrimWord("NUMBER", () -> begin
 
     wordLen = popPS()
@@ -753,7 +754,9 @@ end)
 
 # Compilation
 
-CREATE = defPrimWord("CREATE", () -> begin
+STATE, STATE_CFA = defNewVar("STATE", 0)
+
+HEADER = defPrimWord("HEADER", () -> begin
 
     wordLen = popPS()
     wordAddr = popPS()
@@ -795,7 +798,7 @@ HIDE = defWord("HIDE",
 
 COLON = defWord(":",
     [WORD,
-    CREATE,
+    HEADER,
     LIT, DOCOL, COMMA,
     LATEST_CFA, FETCH, HIDDEN,
     RBRAC,
@@ -814,9 +817,33 @@ IMMEDIATE = defPrimWord("IMMEDIATE", () -> begin
 end, flags=F_IMMED)
 
 TICK = defWord("'",
-    [STATE_CFA, FETCH, ZBRANCH, 7,
-    FROMR, DUP, INCR, TOR, FETCH, EXIT,
-    WORD, FIND, TOCFA, EXIT])
+    [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)
+    
 
 # Strings
 
@@ -872,7 +899,7 @@ INTERPRET = defPrimWord("INTERPRET", () -> begin
         isImmediate = (mem[wordAddr+1] & F_IMMED) != 0
         callPrim(mem[TOCFA])
 
-        callPrim(mem[ROT]) # get rid of extra copy of word string details
+        callPrim(mem[NROT]) # get rid of extra copy of word string details
         popPS()
         popPS()
 
@@ -1020,6 +1047,8 @@ function run(;initialize=true)
 
             mem[STATE] = 0
             mem[NUMTIB] = 0
+            reg.PSP = mem[PSP0]
+            reg.RSP = mem[RSP0]
             reg.IP = QUIT + 1
             jmp = NEXT
         end