math stuff

3 files changed, 98 insertions, 9 deletions

diff --git a/readme.md b/readme.md
index 43b0da8..7e93f2f 100644
--- a/readme.md
+++ b/readme.md
@@ -1,7 +1,6 @@
 # sanctuary (working title)
 
-sanctuary is a 64-bit subroutine threaded forth system
-for amd64 linux systems.
+sanctuary is a 64-bit subroutine threaded forth for amd64 linux systems.
 
 ## stack effect notation
 
@@ -26,6 +25,26 @@ create a dictionary header for a word named the provided string.
 this word does not set the code field.
 this word returns an incompleted xt and does not update latest.
 
+### `*   ( u1 u2 -- u)`
+multiply u1 and u2.
+
+### `*/mod   ( n1 n2 n3 -- n4 n5 )`
+multiply n1 and n2, divide the result by n3.
+remainder is in n3, result is in n4
+
+### `+   ( u1 u2 -- u )`
+add u2 to u1.
+
+### `-   ( u1 u2 -- u )`
+subtract u2 from u1.
+
+### `-rot   ( u1 u2 u3 -- u3 u1 u2 )`
+rotate the three topmost values on the stack so that the topmost value
+is moved to the third highest.
+
+### `/mod   ( u1 u2 -- u3 u4 )`
+divide u1 by u2. result is in u4, remainder is in u3.
+
 ### `[   ( -- ) IMMEDIATE`
 set the system to interpret mode.
 
@@ -38,10 +57,6 @@ start compilation of the word 'name'.
 ### `;   ( -- ) IMMEDIATE`
 end compilation of the currently compiling word.
 
-### `-rot   ( u1 u2 u3 -- u3 u1 u2 )`
-rotate the three topmost values on the stack so that the topmost value
-is moved to the third highest.
-
 ### `>body   ( xt -- a )`
 yield the code field of xt.
 
@@ -58,6 +73,9 @@ remove the two topmost values from the stack.
 ### `2dup   ( u1 u2 -- u1 u2 u1 u2 )`
 duplicate the two topmost values on the stack.
 
+### `and   ( u1 u2 -- u )`
+perform bitwise AND on u1 and u2.
+
 ### `brk@   ( -- a )`
 yields current program break.
 
@@ -103,6 +121,9 @@ true if xt is marked immediate, false otherwise.
 interprets the contents of the terminal input buffer
 until it runs out.
 
+### `invert   ( u -- u')`
+invert all bytes in u.
+
 ### `latest   ( -- a )`
 a variable containing the execution token of
 the most recently created word.
@@ -115,6 +136,9 @@ convert given string into a number along with a flag.
 if parsing a number fails then 0 (false) is returned
 and no number is provided.
 
+### `or  ( u1 u2 -- u )`
+perform bitwise OR on u1 and u2.
+
 ### `parse   ( "name<c>" c -- a u )`
 parse one word from the input buffer,
 separated by a newline or the character c,
@@ -174,6 +198,9 @@ write u characters at a to output.
 ### `over   ( u1 u2 -- u1 u2 u1 )`
 copy the second-highest value on the stack and move it to the top of the stack.
 
+### `xor   ( u1 u2 -- u )`
+perform bitwise XOR on u1 and u2.
+
 ## dictionary format
 
 note that the string length of one byte limits a word's name to 255 characters.
diff --git a/sanctuary.fs b/sanctuary.fs
index 43dc7bb..8b13789 100644
--- a/sanctuary.fs
+++ b/sanctuary.fs
@@ -1,3 +1 @@
-: .s2  1 2 3 [ 7 ] literal .s ;
-4 5 6 .s2
-bye
+
diff --git a/sanctuary.s b/sanctuary.s
index f9fc5f0..44cd4af 100644
--- a/sanctuary.s
+++ b/sanctuary.s
@@ -449,6 +449,7 @@ defcode "(header)", brac_header, 0
 	pspush r12
 	ret
 
+; fix to follow ans: yielding colon-sys
 defcode ":", colon, 0
 	call parse_name
 	; todo check zero
@@ -459,6 +460,8 @@ defcode ":", colon, 0
 	mov qword [state], COMPILING
 	ret
 
+; fix to follow ans: reading from colon-sys
+; this will not work with :noname or i think does>.
 defcode ";", semicolon, immediate_mask
 	mov r12, [latest]
 	add r12, 8
@@ -659,6 +662,67 @@ defcode "rdrop", rdrop, 0
 ; }}}
 
 ; math + comparison {{{
+; i believe some of these could be improved by direct accesses to [r15]
+defcode "+", plus, 0
+	pspop r11
+	pspop r12
+	add r11, r12
+	pspush r11
+	ret
+
+defcode "-", minus, 0
+	pspop r11
+	pspop r12
+	sub r12, r11
+	pspush r12
+	ret
+
+defcode "*", _times, 0
+	pspop r11
+	pspop r12
+	imul r11, r12
+	pspush r11
+	ret
+
+defcode "/mod", divmod, 0
+	xor rdx, rdx
+	pspop r11
+	pspop rax
+	idiv r11
+	pspush rdx
+	pspush rax
+	ret
+
+defcode "and", _and, 0
+	pspop r11
+	and [r14], r11
+	ret
+
+defcode "or", _or, 0
+	pspop r11
+	or [r14], r11
+	ret
+
+defcode "xor", _xor, 0
+	pspop r11
+	xor [r14], r11
+	ret
+
+defcode "invert", invert, 0
+	not qword [r14]
+	ret
+
+defcode "*/mod", starslashmod, 0
+	pspop r15 ; n3
+	pspop r13 ; n2
+	pspop rax ; n1
+
+	imul r13
+	idiv r15
+
+	pspush rdx
+	pspush rax
+	ret
 ; }}}
 
 ; TEMPORARY WONKY DEBUGGING FUNCTIONS {{{