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Merge pull request #97 from rikardn/get_FAC1_via_INDEX

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Add get_FAC1_via_INDEX
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FeralChild64 authored and GitHub committed 2025-04-05 17:34:05 +00:00
2 parents 919f3c84b9 5a3f65efa4
commit 00122b544a
18 files changed
+130 -134
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STATUS.md
+1 -1
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@@ -222,7 +222,7 @@ Floating point mathematical routines - not official, but well known and broadly
| `$BB0F` | `div_MEM_FAC1` | DONE | |
| `$BB12` | `div_FAC2_FAC1` | DONE | |
| `$BBA2` | `mov_MEM_FAC1` | DONE | |
| `$BBA6` | `get_FAC2_via_INDEX` | NOT DONE | |
| `$BBA6` | `get_FAC1_via_INDEX` | DONE | |
| `$BBC7` | `mov_r_FAC1_TMP2` | PARTIAL | not fully tested yet |
| `$BBCA` | `mov_r_FAC1_TMP1` | PARTIAL | not fully tested yet |
| `$BBD0` | `mov_r_FAC1_VAR` | PARTIAL | not fully tested yet |
src/basic/,stubs_math/bba6.get_FAC1_via_INDEX.s
-17
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@@ -1,17 +0,0 @@
;; #LAYOUT# STD * #TAKE
;; #LAYOUT# X16 BASIC_0 #TAKE-OFFSET 2000
;; #LAYOUT# * BASIC_0 #TAKE
;; #LAYOUT# * * #IGNORE
;
; Math package - XXX
;
; See also:
; - https://sourceforge.net/p/acme-crossass/code-0/38/tree/trunk/ACME_Lib/cbm/c64/float.a?force=True
;
; XXX implement, test
get_FAC1_via_INDEX:
+STUB_IMPLEMENTATION
src/basic/math/FCOMP.s
+12 -14
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@@ -32,11 +32,9 @@ FCOMP:
php
ldy #$01
lda #$7F ; Expand sign of RAM float into A as $FF or $00
cmp (INDEX+2),Y
adc #$80
cmp FAC1_sign
bne FCOMP_greater_than ; FAC < or > RAM, will be swapped to correct
lda (INDEX+2),Y
eor FAC1_sign ; Check if signs are different
bmi FCOMP_greater_than ; FAC < or > RAM, will be swapped to correct
dey
lda (INDEX+2),Y ; Exponent of RAM float into A
@@ -76,17 +74,17 @@ FCOMP_equal:
FCOMP_less_than:
lda #$FF
cmp FAC1_sign
bne @1
lda FAC1_sign
bpl FCOMP_FF
FCOMP_01:
lda #$01
@1: plp
plp
rts
FCOMP_greater_than:
lda #$01
cmp FAC1_sign
bcs @1
lda FAC1_sign
bpl FCOMP_01
FCOMP_FF:
lda #$FF
@1: plp
plp
rts
src/basic/math/bc2b.sgn_FAC1_A.s
+5 -1
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@@ -20,7 +20,11 @@ sgn_FAC1_A:
lda FAC1_exponent
beq @1
lda FAC1_sign
bne @1
bmi @2
lda #$01
@1:
rts
@2:
lda #$FF
rts
src/basic/math_mov/ba90.get_FAC2_via_INDEX.s
+1 -11
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@@ -33,20 +33,10 @@ get_FAC2_via_INDEX:
dey
lda (INDEX), y
sta FAC2_sign
ora #$80 ; clear the sign bit
sta FAC2_mantissa+0
; Copy the sign
lda (INDEX), y
bpl @1 ; assumption: non-negative numbers are more frequent
lda #$FF
+skip_2_bytes_trash_nvz
@1:
lda #$00
sta FAC2_sign
; Copy the exponent
dey
src/basic/math_mov/bba2.mov_MEM_FAC1.jmp.s
-8
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@@ -1,8 +0,0 @@
;; #LAYOUT# STD * #TAKE
;; #LAYOUT# X16 BASIC_0 #TAKE-OFFSET 2000
;; #LAYOUT# * BASIC_0 #TAKE
;; #LAYOUT# * * #IGNORE
; Just a compatibility jump - our routine is longer than original one
jmp mov_MEM_FAC1
src/basic/math_mov/bba2.mov_MEM_FAC1.s
+30
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@@ -0,0 +1,30 @@
;; #LAYOUT# STD * #TAKE
;; #LAYOUT# X16 BASIC_0 #TAKE-OFFSET 2000
;; #LAYOUT# * BASIC_0 #TAKE
;; #LAYOUT# * * #IGNORE
; Math package - fetch FAC1 from RAM location
;
; Input:
; - .A - address low byte
; - .Y - address high byte
;
; Output:
; - .A - FAC1 exponent, affects status flags
; - .Y - always 0
;
; Preserves:
; - .X - (experimentation with original ROM)
;
; See also:
; - https://www.c64-wiki.com/wiki/Floating_point_arithmetic
; - https://codebase64.org/doku.php?id=base:kernal_floating_point_mathematics
mov_MEM_FAC1:
sty INDEX+1
sta INDEX+0
; FALLTHROUGH to get_FAC1_via_INDEX
src/basic/math_mov/bba6.get_FAC1_via_INDEX.s
+45
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@@ -0,0 +1,45 @@
;; #LAYOUT# STD * #TAKE
;; #LAYOUT# X16 BASIC_0 #TAKE-OFFSET 2000
;; #LAYOUT# * BASIC_0 #TAKE
;; #LAYOUT# * * #IGNORE
; Math package - Mov MEM to FAC1 with address in INDEX zero page register
;
; See also:
; - https://sourceforge.net/p/acme-crossass/code-0/38/tree/trunk/ACME_Lib/cbm/c64/float.a?force=True
;
get_FAC1_via_INDEX:
; Copy the mantissa
ldy #$04
lda (INDEX), y
sta FAC1_mantissa+3
dey
lda (INDEX), y
sta FAC1_mantissa+2
dey
lda (INDEX), y
sta FAC1_mantissa+1
dey
lda (INDEX), y
sta FAC1_sign
ora #$80 ; clear the sign bit
sta FAC1_mantissa+0
; Copy the exponent
dey
lda (INDEX), y
sta FAC1_exponent
; Set low order mantissa to 0 - this should give the
; most precision while operating on integers
sty FACOV
rts
src/basic/,stubs_math/bba6.interop → src/basic/math_mov/bba6.interop
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File renamed without changes.
src/basic/math_mov/mov_MEM_FAC1.s
-79
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@@ -1,79 +0,0 @@
;; #LAYOUT# STD * #TAKE
;; #LAYOUT# * BASIC_0 #TAKE
;; #LAYOUT# * * #IGNORE
; Math package - fetch FAC1 from RAM location
;
; Input:
; - .A - address low byte
; - .Y - address high byte
;
; Output:
; - .A - FAC1 exponent, affects status flags
; - .Y - always 0
;
; Preserves:
; - .X - (experimentation with original ROM)
;
; See also:
; - https://www.c64-wiki.com/wiki/Floating_point_arithmetic
; - https://codebase64.org/doku.php?id=base:kernal_floating_point_mathematics
; XXX test this
mov_MEM_FAC1:
; Original routines use $22/$23 location for a vector too, see here:
; - https://codebase64.org/doku.php?id=base:kernal_floating_point_mathematics
sty INDEX+1
sta INDEX+0
; Now copy the data from RAM to FAC2, for the format description see:
; - https://www.c64-wiki.com/wiki/Floating_point_arithmetic#Representation_in_the_C-64
; Copy the mantissa
ldy #$04
lda (INDEX), y
sta FAC1_mantissa+3
dey
lda (INDEX), y
sta FAC1_mantissa+2
dey
lda (INDEX), y
sta FAC1_mantissa+1
dey
lda (INDEX), y
ora #$80 ; clear the sign bit
sta FAC1_mantissa+0
; Copy the sign
lda (INDEX), y
bpl @1 ; assumption: non-negative numbers are more frequent
lda #$FF
+skip_2_bytes_trash_nvz
@1:
lda #$00
sta FAC1_sign
; Copy the exponent
dey
lda (INDEX), y
sta FAC1_exponent
; Set low order mantissa to 0 - this should give the
; most precision while operating on integers
sty FACOV
; Return the FAC1 exponent
lda FAC1_exponent
rts
strings/04B122856588B122856488B122856388B12285660980856288B1228561847060
+3
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@@ -0,0 +1,3 @@
$04 + LDA ($22),Y + STA $65 + DEY + LDA ($22),Y + STA $64 + DEY + LDA ($22),Y + STA $63 + DEY + LDA ($22),Y + STA $66 + ORA #$80 + STA $62 + DEY + LDA ($22),Y + STA $61 + STY $70 + RTS
Load FAC1 (well known zero page locations) from memory using well known vector in zero page (INDEX)
strings/20A2BB4C
+3
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@@ -0,0 +1,3 @@
JSR $BBA2 + JMP fragment
Call to well known floating point function + fragment
strings/60202BBC85
+5
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@@ -0,0 +1,5 @@
60 20 2B BC 85
RTS + JSR $BC2B + STA fragment
Fragments + call to well known floating point function
strings/6E0980856A88B1228569A56160
+3
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@@ -0,0 +1,3 @@
$6E + ORA #$80 + STA $6A + DEY + LDA ($22),Y + STA $69 + LDA $61 + RTS
Fragment of copying using a well known index vector from a mem float into FAC2
strings/A004B122856D88B122856C88B122856B88B122856E
+3
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@@ -0,0 +1,3 @@
LDY #$04 + LDA ($22),Y + STA $6D + DEY + LDA ($22),Y + STA $6C + DEY + LDA ($22),Y + STA $6B + DEY + LDA ($22),Y + STA $6E
Load parts of the mantissa of FAC2 and its sign (well known zero page locations) from memory using well known vector in zero page (INDEX)
strings/A9A8A0AE20A2BB4C
+3
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@@ -0,0 +1,3 @@
LDA #$A8 + LDY #$AE + JSR $BBA2 + JMP fragment
Loading well known address of math constant pi into AY and call well known floating point function (mov_MEM_FAC1)
strings/B124456630
+3
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@@ -0,0 +1,3 @@
LDA ($24),Y + EOR $66 + BMI fragment
Compare signs of FAC1 and float pointed to by index vector
testsuite/unit/math.vs
+13 -3
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@@ -139,12 +139,22 @@ r A=$E0
r Y=$B9
r PC=$BBA2
ret
fill $1001 $1006 80 80 00 00 00 FF
fill $1001 $1006 80 80 00 00 00 80
print "COMPARE"
compare $61 $66 $1001
compare $70 $70 $1003 ; FACOV = 0
print "END"
print "TEST: get_FAC1_via_INDEX -0.5"
fill $61 $66 FF FF FF FF FF AA
fill $22 $23 E0 B9
r PC=$BBA6
ret
fill $1001 $1006 80 80 00 00 00 80
print "COMPARE"
compare $61 $66 $1001
print "END"
print "TEST: mov MEM FAC2 const 1.0"
fill $69 $6E FF FF FF FF FF AA
r A=$BC
@@ -162,7 +172,7 @@ r A=$E0
r Y=$B9
r PC=$BA8C
ret
fill $1001 $1006 80 80 00 00 00 FF
fill $1001 $1006 80 80 00 00 00 80
print "COMPARE"
compare $69 $6E $1001
print "END"
@@ -172,7 +182,7 @@ fill $69 $6E FF FF FF FF FF AA
fill $22 $23 E0 B9
r PC=$BA90
ret
fill $1001 $1006 80 80 00 00 00 FF
fill $1001 $1006 80 80 00 00 00 80
print "COMPARE"
compare $69 $6E $1001
print "END"