vm

ka/crt/fmt/doprnt.k

@@ -197,7 +197,7 @@ doprnt:
     call nx3
     
     ; did putc fail?
-    cmp rax, 0
+    test rax, rax
     xor.nz nx0, nx0     ; yes, so artificially set n=0
 
     ret

ka/crt/fmt/ltostr.k

@@ -12,7 +12,7 @@ itoa:
 ; void utoa(char *buf, int num, int base)
 ;
 utoa:
-    sub ax3, ax3
+    xor ax3, ax3
     jmp ltostr
 
 ;
@@ -44,8 +44,7 @@ ltostr:
 .conv:
     b.e ax1, 0, .fini
 
-    mov r10, ax1
-    rem r10, ax2    ; ax1 % base
+    rem r10, ax1, ax2    ; ax1 % base
 
     b.a r10, 9, .nondec      ; r10 > 9 ?
 

ka/crt/fmt/strtol.k

@@ -18,7 +18,7 @@ strtol:
 ; rdx = pointer to first invalid byte
 ;
 strtoul:
-    sub ax2, ax2
+    xor ax2, ax2
     jmp strtoq
 
 ;
@@ -48,7 +48,7 @@ strtoq:
 
     ; signed?
     test ax2, ax2
-    sub.z r10, r10
+    xor.z r10, r10
     jmp.z .unsigned
 
     ; parse '-'

ka/crt/str/strlen.k

@@ -7,9 +7,8 @@
 strnlen:
     mov rcx, ax1
     scasb.rep.nz ax0, 0
-    
-    mov rax, ax1
-    sub rax, rcx
+
+    sub rax, ax1, rcx
     ret
 
 ;

ka/usr/cmd/dir.k

@@ -79,8 +79,7 @@ CMD.builtins.dir:
     prn ' '
     prn ' '
 
-    mov rax, rdx
-    shr rax, 10
+    shr rax, rdx, 10
     and rdx, 1023
 
     mov ax0, .bytesstr

vm/in/LOGIC

@@ -29,8 +29,7 @@ not r r
 #
 #       $dest = $src1 OR $src2
 #
-# Clears OF and CF
-# Sets ZF and SF according to the result
+# Preserves all flags
 #
 or r ri
 or r r ri
@@ -50,8 +49,7 @@ nor r r ri
 #
 #       $dest = $src1 AND $src2
 #
-# Clears OF and CF
-# Sets ZF and SF according to the result
+# Preserves all flags
 #
 and r rim
 and r r rim
@@ -71,8 +69,7 @@ nand r r ri
 # 
 #       $dest = $src1 XOR $src2
 #
-# Clears OF and CF
-# Sets ZF and SF according to the result
+# Preserves all flags
 #
 xor r rim
 xor r r rim
@@ -89,15 +86,23 @@ xnor r r ri
 
 # To document
 
-shl r rim
+shl r ri
+shl r r ri
 shl m ri
+shl m r ri
 
-shr r rim
+shr r ri
+shr r r ri
 shr m ri
+shr m r ri
 
-sal r rim
+sal r ri
+sal r r ri
 sal m ri
+sal m r ri
 
-sar r rim
+sar r ri
+sar r r ri
 sar m ri
+sar m r ri
 

vm/in/MOV

@@ -88,7 +88,7 @@ rotl rm r r
 # Throws:
 #       #ILL if $2 ≥ 16
 #
-ldarg r ri
+ldarg r r
 
 #
 # Get code/data offset (GCO/GCD)