duskos

commit d6fdd2977e6803dd7fd95d08d5837b1f0de76679
parent fcf5a2102457bf094bb79b73900f078027d23c81
Author: Virgil Dupras <hsoft@hardcoded.net>
Date:   Sun,  2 Jul 2023 14:55:19 -0400

hal i386: support disp32 in +)

*still* no luck with that ar/ungz failure. Will I have to dig in puff.c source
to find that bug?

Diffstat:
M
fs/tests/hal.fs
 | 
7
+++++++
M
fs/xcomp/i386/kernel.fs
 | 
24
+++++++++++++++++-------

2 files changed, 24 insertions(+), 7 deletions(-)
diff --git a/fs/tests/hal.fs b/fs/tests/hal.fs
@@ -294,4 +294,11 @@ code test32 ( a b -- a<<b )
   PSP) <>) <<, drop, exit,
 
 $2a 4 test32 $2a0 #eq
+
+\ Test that +) can be more than a byte
+create foo $100 allot0 42 ,
+code test33 ( a -- [a+$100] )
+  W) $100 +) 8b) @, exit,
+
+foo test33 42 #eq
 testend
diff --git a/fs/xcomp/i386/kernel.fs b/fs/xcomp/i386/kernel.fs
@@ -156,15 +156,15 @@ xcode hbank' ( slot -- a ) \ preserves DX and DI
   ax lblhbank i) add,
   ret,
 
-xcode hbank! ( n -- slot )
+xcode hbank! ( n -- slot ) \ Preserves DI
   dx ax mov,
   ax lblhbankidx m) mov,
   ax $f i) and,
-  di ax mov,
+  ax push,
   lblhbankidx m) inc,
   wcall, hbank'
   ax 0 d) dx mov,
-  ax di mov,
+  ax pop,
   ret,
 
 xcode hbank@ ( slot -- n )
@@ -173,7 +173,7 @@ xcode hbank@ ( slot -- n )
   ret,
 
 \ Create a new "banked" operand from n
-pc to lblnewbankedop ( n -- operand )
+pc to lblnewbankedop ( n -- operand ) \ preserves DI
   wcall, hbank!
   ax 20 i) shl,
   ax HALHASBANK i) or,
@@ -194,6 +194,14 @@ xcode i) ( n -- operand )
   ax HALIMM i) or,
   ret,
 
+\ If operand's mod is 1 (disp8) and that n >= $100, upgrade mod to 2 (disp32)
+pc to L2 ( operand -- operand ) \ di=n
+  di $ffffff00 i) test, forward8 jnz, ret, forward!
+  cl al mov, cl $c0 i) and, cl $40 i) cmp, forward8 jz, ret, forward!
+  \ upgrade needed
+  al $40 i) add,
+  ret,
+
 \ When the operation already has a banked op, add to it instead of replacing it.
 pc to L1 ( operand n -- operand )
   ax push, xdrop, ax push,
@@ -201,18 +209,19 @@ pc to L1 ( operand n -- operand )
   wcall, hbank'
   dx pop, ( operand ) cx pop, ( n )
   ax 0 d) cx add,
+  di ax 0 d) mov,
   ax dx mov,
-  ret,
+  L2 absjmp,
 
-\ TODO: allow disp32 offsets
 xcode +) ( operand n -- operand )
   ax ax test, forward8 jnz, xdrop, ret, forward!
   si 0 d) HALHASBANK i) test, L1 abs>rel jnz,
+  di ax mov, \ save for L2
   lblnewbankedop abscall,
   dx si 0 d) mov, xnip,
   ax dx or,
   ax $40 i) or, \ disp8 mode
-  ret,
+  L2 absjmp,
 
 xcode 8b) ( operand -- operand )
   ax HAL8B ^ i) and, ret,
@@ -291,6 +300,7 @@ pc to lblmodrmwr ( operand -- )
     $24 i) cwrite, forward! forward! \ mod=3 and rm=SP? write SIB
   dl al mov, dl $c0 i) and, \ dl=mod
   dl $40 i) cmp, L2 abs>rel jz, \ disp8
+  dl $80 i) cmp, L3 abs>rel jz, \ disp32
   dl al mov, 0 dl reg!,
   dl $05 i) cmp, L3 abs>rel jz, \ m) means disp32
   xdrop, ret,