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forth: a little bit of ASM routine inlining

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This commit is contained in:
Virgil Dupras 2020-03-30 21:33:37 -04:00
parent 5c03b33982
commit e5ab0dd1c9
3 changed files with 13 additions and 30 deletions
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2
emul/forth/stage.c
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@ -29,7 +29,7 @@ trouble of compiling defs to binary.
//#define DEBUG //#define DEBUG
// in sync with glue.asm // in sync with glue.asm
#define RAMSTART 0x850 #define RAMSTART 0x840
#define STDIO_PORT 0x00 #define STDIO_PORT 0x00
// To know which part of RAM to dump, we listen to port 2, which at the end of // To know which part of RAM to dump, we listen to port 2, which at the end of
// its compilation process, spits its HERE addr to port 2 (MSB first) // its compilation process, spits its HERE addr to port 2 (MSB first)

BIN
emul/forth/z80c.bin
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41
forth/forth.asm
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@ -190,17 +190,6 @@ forthMain:
.bootName: .bootName:
.db "BOOT", 0 .db "BOOT", 0
; copy (HL) into DE, then exchange the two, utilising the optimised HL instructions.
; ld must be done little endian, so least significant byte first.
intoHL:
push de
ld e, (hl)
inc hl
ld d, (hl)
ex de, hl
pop de
ret
; Compares strings pointed to by HL and DE until one of them hits its null char. ; Compares strings pointed to by HL and DE until one of them hits its null char.
; If equal, Z is set. If not equal, Z is reset. C is set if HL > DE ; If equal, Z is set. If not equal, Z is reset. C is set if HL > DE
strcmp: strcmp:
@ -225,19 +214,6 @@ strcmp:
; early, set otherwise) ; early, set otherwise)
ret ret
; Given a string at (HL), move HL until it points to the end of that string.
strskip:
push bc
ex af, af'
xor a ; look for null char
ld b, a
ld c, a
cpir ; advances HL regardless of comparison, so goes one too far
dec hl
ex af, af'
pop bc
ret
; Parse string at (HL) as a decimal value and return value in DE. ; Parse string at (HL) as a decimal value and return value in DE.
; Reads as many digits as it can and stop when: ; Reads as many digits as it can and stop when:
; 1 - A non-digit character is read ; 1 - A non-digit character is read
@ -376,8 +352,10 @@ find:
dec de \ dec de \ dec de ; prev field dec de \ dec de \ dec de ; prev field
push de ; --> lvl 2 push de ; --> lvl 2
ex de, hl ex de, hl
call intoHL ld e, (hl)
ex de, hl ; DE contains prev offset inc hl
ld d, (hl)
; DE contains prev offset
pop hl ; <-- lvl 2 pop hl ; <-- lvl 2
; HL is prev field's addr ; HL is prev field's addr
; Is offset zero? ; Is offset zero?
@ -543,8 +521,13 @@ numberWord:
litWord: litWord:
ld hl, (IP) ld hl, (IP)
push hl push hl
call strskip ; Skip to null char
inc hl ; after null termination xor a ; look for null char
ld b, a
ld c, a
cpir
; CPIR advances HL regardless of comparison, so goes one char after
; NULL. This is good, because that's what we want...
ld (IP), hl ld (IP), hl
jp next jp next
@ -558,5 +541,5 @@ litWord:
.dw $-EXECUTE .dw $-EXECUTE
.db 5 .db 5
; Offset: 0249 ; Offset: 0237
.out $ .out $