commit fa861cdc04e2d98aa158c118b16466a013dc38ab
parent a2e9e3f148bb24a0bd6d9d2a0de78b0a5da54cb5
Author: Virgil Dupras <hsoft@hardcoded.net>
Date: Thu, 6 Apr 2023 07:22:21 -0400
hal: slightly rework the API
Rename some ops and remove <<n, and >>n, which aren't worth their weight in the
Low HAL as they're only used by "<<" and ">>". They're then replaced by High
HAL's "<<," and ">>," and become useless. Might as well move "<<" and ">>" in
the kernel.
Diffstat:
8 files changed, 31 insertions(+), 36 deletions(-)
diff --git a/fs/asm/i386.fs b/fs/asm/i386.fs
@@ -277,9 +277,8 @@ $e2 op loop, $e1 op loopz, $e0 op loopnz,
op @, ?movzx, op @!, xchg, op addr, lea,
: !, <>) @, ;
-\ TODO: in 32-bit mode, arithmetics can be done directly, no need for bx
: op doer ' , does> @ ( halop w ) dip halop>dstsrc ( dst src )
- bx swap ?movzx, bx | execute ;
+ bi+ 16b? | 8b? or if bx swap ?movzx, bx then | execute ;
op +, add, op -, sub, op compare, cmp,
: *,
@@ -290,6 +289,7 @@ op +, add, op -, sub, op compare, cmp,
dup imm? not if cx swap mov, cl then | execute ;
op <<, shl, op >>, shr,
+: [+n], ( n halop -- ) halop>dstsrc nip swap i) add, ;
: _ ( halop -- dst src )
dup 16b? >r dup 8b? >r 32b)
halop>dstsrc bx swap mov, ( dst )
diff --git a/fs/comp/c/egen.fs b/fs/comp/c/egen.fs
@@ -27,7 +27,7 @@ alias noop parseFactor ( tok -- res ) \ forward declaration
over Result :isconst? if
CELLSZ + @ over Result arg swap execute over to Result arg
else @ over Result :?>W execute then ( res ) ;
-unaryop _neg, negate, neg
+unaryop _neg, -W, neg
: _ -1 i) ^, ;
unaryop _not, _ ^
: _ W=0>Z, Z) C>W, ;
diff --git a/fs/comp/c/fgen.fs b/fs/comp/c/fgen.fs
@@ -84,7 +84,7 @@ code _lookup ( nref lookup -- )
1 RSP) [+n], CELLSZ A+n, A) @,
PSP) compare, NZ) branchC, drop \ Z=match
\ we have a match, add totcnt*CELLSZ to A, dereference. that's our target.
- RSP) 4 +) @, 2 <<n, RSP) !, W<>A, RSP) +, W) @, \ W=target
+ RSP) 4 +) @, 2 i) <<, RSP) !, W<>A, RSP) +, W) @, \ W=target
12 rs+, W>A, nip, branchA,
\ Switch works by constructing a lookup table of all the cases and generating
diff --git a/fs/doc/design/simple.txt b/fs/doc/design/simple.txt
@@ -13,13 +13,14 @@ innovation compared to other Forths is to include a C compiler, my main
reference when comparing complexity is Fabrice Bellard's Tiny C Compiler.
Tcc enjoys a very good reputation among geeks, and Fabrice Bellard is generally
-considered to be a genius. Nevertheless, Dusk's C compiler, excluding backends,
-is 1300 lines of code and tcc, excluding backend is roughly 30,000 lines of
-code. At the time of this writing, Dusk CC isn't quite completed yet, but there
-isn't much left to add, I don't think it will exceed 2000 lines by much.
+considered to be a genius. Nevertheless, Dusk's C compiler, excluding
+assemblers, is 1400 lines of code and tcc, excluding backends is roughly 30,000
+lines of code. At the time of this writing, Dusk CC isn't quite completed yet,
+but there isn't much left to add, I don't think it will exceed 2000 lines by
+much.
-The i386 backend of Dusk CC, including its assembler, is 600 lines of code. In
-tcc, the i386 backend weighs in at 1600 lines of code.
+The i386 backend (the HAL) of Dusk CC, including its assembler, is 400 lines of
+code. In tcc, the i386 backend weighs in at 1600 lines of code.
How can we explain this difference? It's true that Forth code is generally
denser than C, but not by a factor of 15. It's true that I'm sometimes clever,
diff --git a/fs/doc/hal.txt b/fs/doc/hal.txt
@@ -194,15 +194,15 @@ branchA, --
Instructions:
-@, op -- Read source into dest
-!, op -- Write dest to source
-@!, op -- Swap dest and source
-+, op -- *Z* Add source to dest
-[@], op -- Read indirect source into dest
-[!], op -- Write indirect source into dest
-compare, op -- Compare source to dest
-[+n], n op -- *Z* Add n to indirect source without affecting dest
-&, op -- Store the effective address of the operand in dest
+@, op -- Read source into dest
+!, op -- Write dest to source
+@!, op -- Swap dest and source
++, op -- *Z* Add source to dest
+[@], op -- Read indirect source into dest
+[!], op -- Write indirect source into dest
+compare, op -- Compare source to dest
+[+n], n op -- *Z* Add n to indirect source without affecting dest
+addr, op -- Store the effective address of the operand in dest
ps+, n -- Add n to PSP
rs+, n -- Add n to RSP
@@ -211,9 +211,7 @@ A+n, n -- *Z* Add n to A
W>A, -- Copy W to A
A>W, -- Copy A to W
W<>A, -- Swap W and A
-negate, -- dest = -dest
-<<n, n -- Shift dest left by n
->>n, n -- Shift dest right by n
+-W, -- W = -W
## High HAL
diff --git a/fs/tests/asm/hal.fs b/fs/tests/asm/hal.fs
@@ -172,7 +172,7 @@ code test17 ( n -- )
\ test &). this returns item "idx" from PSP
code test18 ( ... idx -- n )
- 2 <<n, PSP) &) +, W) @,
+ 2 i) <<, PSP) &) +, W) @,
exit,
42 12 123 0 test18 123 #eq
diff --git a/fs/xcomp/bootlo.fs b/fs/xcomp/bootlo.fs
@@ -4,8 +4,6 @@ code : ] code ] ;
: noop ;
code dup dup, exit,
code swap PSP) @!, exit,
-code << 1 <<n, exit,
-code >> 1 >>n, exit,
: nip, 4 ps+, ;
code nip nip, exit,
: drop, PSP) @, nip, ;
@@ -55,7 +53,7 @@ code16b W>A, drop, A) 16b) [!], 2 A) [+n], drop, exit,
code8b W>A, drop, A) 8b) [!], 1 A) [+n], drop, exit,
code + PSP) +, nip, exit,
-code - negate, PSP) +, nip, exit,
+code - -W, PSP) +, nip, exit,
: -^ swap - ;
: e>w 5 + ;
: w>e 5 - ;
@@ -108,7 +106,7 @@ code ?dup W=0>Z, 0 Z) branchC, dup, then exit,
: min ?swap drop ; : max ?swap nip ;
: max0 ( n -- n ) dup 0< if drop 0 then ;
: =><= ( n l h -- f ) over - rot> ( h n l ) - >= ;
-code neg negate, exit,
+code neg -W, exit,
: ^ -1 xor ;
: and? bool swap bool and ;
: or? or bool ;
diff --git a/fs/xcomp/i386/kernel.fs b/fs/xcomp/i386/kernel.fs
@@ -284,14 +284,6 @@ xcode litn
wcall, dup,
wjmp, LIT>W,
-xcode <<n, ( n -- ) \ ax XX i) shl,
- $e0c1 i) wwrite, al cwrite,
- xdrop, ret,
-
-xcode >>n, ( n -- ) \ ax XX i) shr,
- $e8c1 i) wwrite, al cwrite,
- xdrop, ret,
-
pc 3 nc, $5b $ff $d3 \ bx pop, bx call,
xcode yield ximm
( pc ) 3 movewrite, ret,
@@ -304,7 +296,7 @@ xcode exit,
$c3 ( ret ) i) cwrite,
ret,
-xcode negate, ( -- ) \ ax neg,
+xcode -W, ( -- ) \ ax neg,
$d8f7 i) wwrite, ret,
xcode W=0>Z, $c085 i) wwrite, ret, \ ax ax test,
@@ -351,6 +343,12 @@ xcode /mod ( a b -- r q )
si 0 d) dx mov, \ remainder
ret,
+xcode << ( n -- n )
+ ax 1 i) shl, ret,
+
+xcode >> ( n -- n )
+ ax 1 i) shr, ret,
+
xcode lshift ( n u -- n )
cx ax mov, xdrop,
ax cl shl,
