More work on x86 backend.

examples/sysir/drawing2.janet

@@ -7,13 +7,17 @@
 
 (use ./frontend)
 
+(setdyn :verbose true)
+
+# Pointer types
 (defpointer p32 uint)
 (defpointer p16 u16)
 (defpointer cursor p32)
-(defn-external write:void [fd:int mem:pointer size:uint])
-(defn-external exit:void [x:int])
-(defn-external malloc:p32 [x:uint])
-(defn-external free:void [m:p32])
+
+# Linux syscalls
+(defn-syscall brk:p32 12 [amount:uint])
+(defn-syscall exit:void 60 [code:int])
+(defn-syscall write:void 1 [fd:int data:p32 size:uint])
 
 (defsys w32:void [c:cursor x:uint]
   (def p:p32 (load c))
@@ -30,9 +34,11 @@
 
 (defsys makebmp:p32 [w:uint h:uint]
   (def size:uint (+ 56 (* w h 4)))
-  (def mem:p32 (malloc size))
-  (def cursor_data:p32 mem)
-  (def c:cursor (address cursor_data))
+  (def mem:p32 (brk size))
+  #(def cursor_data:p32 mem)
+  #(def c:cursor (address cursor_data))
+  (def c:cursor (cast (brk 4)))
+  (store c mem)
   (w16 c 0x4D42) # ascii "BM"
   (w32 c size)
   (w32 c 0)
@@ -52,27 +58,32 @@
   # Draw
   (def red:uint 0xFFFF0000)
   (def blue:uint 0xFF0000FF)
+  (def green:uint 0xFF00FF00)
   (var y:uint 0)
   (while (< y h)
     (var x:uint 0)
     (while (< x w)
-      (if (> y 64)
-        (w32 c blue)
+      (def d2:uint (+ (* x x) (* y y)))
+      (if (> d2 100000)
+        (if (> d2 200000) (w32 c green) (w32 c blue))
         (w32 c red))
       (set x (+ 1 x)))
     (set y (+ y 1)))
   (write 1 mem size)
   (return mem))
 
-(defsys main:int []
-  (def w:uint 128)
+(defsys _start:void []
+  (def w:uint 512)
   (def h:uint 512)
-  (makebmp w h)
-  (return 0))
+  # (makebmp w h)
+  (def size:uint (+ 56 (* w h 4)))
+  (def mem:p32 (brk size))
+  (store mem (the uint 0x4d424d42))
+  (write 1 mem 4)
+  #(write 1 (cast "hello, world!\n") 14)
+  (exit 0)
+  (return))
 
 ####
 
-#(dump)
-(print "#include <unistd.h>")
-(dumpc)
-#(dumpx64)
+(dumpx64)

examples/sysir/frontend.janet

@@ -12,6 +12,7 @@
 (def slot-types @{})
 (def functions @{})
 (def type-fields @{})
+(def syscalls @{})
 
 (defn get-slot
   [&opt new-name]
@@ -317,20 +318,11 @@
             (array/push into ;args)
             nil)
 
-          # Syscall
-          'syscall
-          (do
-            (def slots @[])
-            (def ret (if no-return nil (get-slot)))
-            (each arg args
-              (array/push slots (visit1 arg into)))
-            (array/push into ~(syscall :default ,ret ,;slots))
-            ret)
-
-          # Assume function call
+          # Assume function call or syscall
           (do
             (def slots @[])
             (def signature (get functions op))
+            (def is-syscall (get syscalls op))
             (assert signature (string "unknown function " op))
             (def ret (if no-return nil (get-slot)))
             (when ret
@@ -338,7 +330,9 @@
               (assign-type ret (first signature)))
             (each [arg-type arg] (map tuple (drop 1 signature) args)
               (array/push slots (visit1 arg into false arg-type)))
-            (array/push into ~(call :default ,ret [pointer ,op] ,;slots))
+            (if is-syscall
+              (array/push into ~(syscall :default ,ret (int ,is-syscall) ,;slots))
+              (array/push into ~(call :default ,ret [pointer ,op] ,;slots)))
             ret)))
 
       (errorf "cannot compile %q" code)))
@@ -478,6 +472,20 @@
         (array/push signature tp))
       (put functions fn-name (freeze signature)))
 
+    # External syscall
+    'defn-syscall
+    (do
+      (def [name sysnum args] rest)
+      (assert (tuple? args))
+      (def [fn-name fn-tp] (type-extract name 'void))
+      (def pcount (length args)) #TODO - more complicated signatures
+      (def signature @[fn-tp])
+      (each arg args
+        (def [name tp] (type-extract arg 'int))
+        (array/push signature tp))
+      (put syscalls fn-name sysnum)
+      (put functions fn-name (freeze signature)))
+
     # Top level function definition
     'defn
     (do
@@ -544,4 +552,5 @@
 (defmacro defarray [& args] [compile1 ~',(keep-syntax! (dyn *macro-form*) ~(defarray ,;args))])
 (defmacro defpointer [& args] [compile1 ~',(keep-syntax! (dyn *macro-form*) ~(defpointer ,;args))])
 (defmacro defn-external [& args] [compile1 ~',(keep-syntax! (dyn *macro-form*) ~(defn-external ,;args))])
+(defmacro defn-syscall [& args] [compile1 ~',(keep-syntax! (dyn *macro-form*) ~(defn-syscall ,;args))])
 (defmacro defsys [& args] [compile1 ~',(keep-syntax! (dyn *macro-form*) ~(defn ,;args))])

examples/sysir/run_drawing2.sh

@@ -0,0 +1,5 @@
+#!/usr/bin/env bash
+valgrind build/janet examples/sysir/drawing2.janet > temp.nasm
+nasm -felf64 temp.nasm -l temp.lst -o temp.o
+ld -o temp.bin -dynamic-linker /lib64/ld-linux-x86-64.so.2 -lc temp.o
+valgrind ./temp.bin