mirror of
https://github.com/fadden/6502bench.git
synced 2024-08-16 15:29:00 +00:00
When we have relocation data available, the code currently skips the process of matching an address with a label for a PEA instruction when the instruction in question doesn't have reloc data. This does a great job of separating code that pushes parts of addresses from code that pushes constants. This change expands the behavior to exclude instructions with 16-bit address operands that use the Data Bank Register, e.g. "LDA abs" and "LDA abs,X". This is particularly useful for code that accesses structured data using the operand as the structure offset, e.g. "LDX addr" / "LDA $0000,X" The 20212-reloc-data test has been updated to check the behavior.
111 lines
2.6 KiB
ArmAsm
111 lines
2.6 KiB
ArmAsm
; Copyright 2020 faddenSoft. All Rights Reserved.
|
|
; See the LICENSE.txt file for distribution terms (Apache 2.0).
|
|
;
|
|
; Assembler: Merlin 32
|
|
;
|
|
; Segment #1 : code; main segment, loads anywhere
|
|
|
|
BANK2_START EXT
|
|
BANK2_MOV_DST EXT
|
|
BANK8_START EXT
|
|
BANK8_ADDR EXT
|
|
BANK8_MOV_SRC EXT
|
|
ADDR_FFE0 EXT
|
|
|
|
; expected to start at $02/0000
|
|
REL ;generate relocatable code
|
|
|
|
start
|
|
clc
|
|
xce
|
|
sep #$30
|
|
mx %11
|
|
|
|
ldal start
|
|
nop
|
|
|
|
jsl BANK2_START
|
|
jsl BANK8_START
|
|
|
|
ldal BANK2_START
|
|
lda BANK2_START
|
|
lda #<BANK2_START
|
|
lda #>BANK2_START
|
|
lda #^BANK2_START
|
|
|
|
ldal BANK8_ADDR
|
|
lda BANK8_ADDR
|
|
lda #<BANK8_ADDR
|
|
lda #>BANK8_ADDR
|
|
lda #^BANK8_ADDR
|
|
nop
|
|
|
|
; Do some stuff with 16-bit registers. Merlin 32 treats <>^ as shift
|
|
; operations rather than byte selectors.
|
|
rep #$30
|
|
mx %00
|
|
lda #<BANK8_ADDR
|
|
lda #>BANK8_ADDR
|
|
lda #^BANK8_ADDR
|
|
nop
|
|
|
|
; Check MVN/MVP. Handing them correctly requires having two different
|
|
; symbol refs on a single instruction.
|
|
lda #15
|
|
ldx #BANK8_MOV_SRC
|
|
ldy #BANK2_MOV_DST
|
|
mvn #^BANK8_MOV_SRC,#^BANK2_MOV_DST
|
|
nop
|
|
|
|
; Test whether we're finding symbols for 16-bit address operands
|
|
; without reloc data.
|
|
lda: $0000,y
|
|
sta: $0002,y
|
|
|
|
check_pea
|
|
pea $0000
|
|
pea $f000
|
|
pea BANK8_ADDR
|
|
pea ^BANK8_ADDR
|
|
pea check_pea
|
|
pea >check_pea
|
|
pea ^check_pea
|
|
pea check_pea+18
|
|
pea check_pea+$1000
|
|
nop
|
|
|
|
jmp :skipdata
|
|
|
|
; Generate 2/3/4-byte refs. The OMF reloc entry generated by Merlin32
|
|
; for ADRL is only 3 bytes wide.
|
|
dw ADDR_FFE0
|
|
adr ADDR_FFE0
|
|
adrl ADDR_FFE0
|
|
|
|
:skipdata
|
|
|
|
; Check a situation where we block a relocation from being fully formed.
|
|
; The access to addr_dat+2 and addr_dat cause labels to be auto-generated.
|
|
; Because we access the high part first, there's no opportunity to find
|
|
; a pre-existing label nearby. If the reloc code generates a 3-byte or
|
|
; 4-byte data item at addr_dat, the label at addr_dat+2 will be hidden.
|
|
phk
|
|
plb
|
|
lda #$0000
|
|
asl A
|
|
asl A
|
|
tax
|
|
lda addr_dat+2,X
|
|
pha
|
|
lda addr_dat,X
|
|
pha
|
|
beq :skip_ad
|
|
rts
|
|
|
|
addr_dat
|
|
adrl check_pea
|
|
adrl :skipdata
|
|
|
|
:skip_ad
|
|
rts
|