1
0
mirror of https://github.com/fadden/6502bench.git synced 2024-12-11 13:50:13 +00:00
Commit Graph

31 Commits

Author SHA1 Message Date
Andy McFadden
92f304a030 Minor fixes
Escape '_' in filenames for the recents menu.

Fix status flag update for ROL.
2021-12-23 11:29:29 -08:00
Andy McFadden
62509d0bd7 Documentation / comment tweaks 2021-09-11 14:12:09 -07:00
Andy McFadden
a7cc9d5a53 Tweak comments 2021-08-21 11:19:16 -07:00
Andy McFadden
34ba47e71d Add W65C02S support, part 3
Modified the asm source generators and on-screen display to show the
DP arg for BBR/BBS as hex.  The instructions are otherwise treated
as relative branches, e.g. the DP arg doesn't get factored into the
cross-reference table.

ACME/cc65 put the bit number in the mnemonic, 64tass wants it to be
in the first argument, and Merlin32 wants nothing to do with any of
this because it's incompatible with the 65816.

Added an "all ops" test for W65C02.
2020-10-11 14:35:17 -07:00
Andy McFadden
70ee8793ae Add W65C02S support, part 2
Created the "all ops" tests for W65C02.  Filled in enough of the
necessary infrastructure to be able to create the project and
disassemble the file, though we're not yet handling the instructions
correctly.
2020-10-10 18:34:19 -07:00
Andy McFadden
b60dc4fee4 Add W65C02S support, part 1
We were claiming W65C02S, but it turns out that CPU has the Rockwell
extensions and the STP/WAI instructions.  We need to change existing
references to be "WDC 65C02", and add a new CPU definition for the
actual W65C02S chip.

This adds the new CPU definition, the instruction definitions for
the Rockwell extensions, and updates the selectors in project properties
and the instruction chart tool.

This change shouldn't affect any existing projects.  Still more to do
before W65C02 works though, mostly because the Rockwell instructions
introduced a new two-argument address mode that has to be handled in
various places.
2020-10-10 15:46:34 -07:00
Andy McFadden
bd5b556a7f Show "ptr" for pointer use in cross-reference list
Consider:
 LDA $00 loads a value from address $00
 LDA $00,X might load from $00, or might not
 LDA ($00),Y dereferences $00 as a 16-bit pointer
 LDA ($00,X) dereferences a pointer, not necessarily from $00

When perusing the cross-reference list, it's useful to be able to
tell whether an instruction is accessing the location, using it as a
base address, or deferencing it as a pointer.  We now show "ptr" in
the list for pointer dereferences.  (We already showed "idx" for
indexed accesses.)
2020-09-04 13:26:41 -07:00
Andy McFadden
ba35f88d02 Mark flags as indeterminate for inline BRK
We weren't altering the status flags after a BRK because of the
assumption that a BRK was a crash.  For an inline BRK, such as a SOS
call, execution continues.  We need to mark NVZC indeterminate or
we may incorrectly handle conditional branches that follow.

The BRK instruction now uses the same flag updater as JSR, since it's
effectively a subroutine call to unknown code.  If execution doesn't
continue across the BRK then the flags don't matter.

Updated 20182-extension-scripts to exercise this.
2020-08-22 08:56:38 -07:00
Andy McFadden
bc15178a8e Tweak M/X/E flag handling
The decision of how to handle indeterminate M/X flag values is made in
StatusFlags.  This provides consistent behavior throughout the app.
This was being done for M/X but not for E.

This change also renames the M/X tests, prefixing them with "Is" to
emphasize that they are boolean rather than tri-state.

There should be no change in behavior from this.
2020-07-06 08:31:18 -07:00
Andy McFadden
fdd2bcf847 Fix some 65816 code generation issues
Two basic problems:

(1) cc65, being a one-pass assembler, can't tell if a forward-referenced
label is 16-bit or 24-bit.  If the operand is potentially ambiguous,
such as "LDA label", we need to add an operand width disambiguator.
(The existing tests managed to only do backward references.)

(2) 64tass wants the labels on JMP/JSR absolute operands to have 24-bit
values that match the current program bank.  This is the opposite of
cc65, which requires 16-bit values.  We need to distinguish PBR vs.
DBR instructions (i.e. "LDA abs" vs. "JMP abs") and handle them
differently when formatting for "Common".

Merlin32 doesn't care, and ACME doesn't work at all, so neither of
those needed updating.

The 20052-branches-and-banks test was expanded to cover the problematic
cases.
2020-07-01 17:59:12 -07:00
Andy McFadden
47c773dcdf Show "idx" for indexed accesses in References window
Sometimes it's useful to know whether an address referenced by a
function is a direct access, or is being used as a base address.
(I'm somewhat undecided on this one, since it clutters up the list
a bit.  Giving it a try.)
2020-05-02 14:09:53 -07:00
Andy McFadden
facaa721de Fix AND/ORA imm flag updater
The code was making an unwarranted assumption about how the flags
were being set.  For example, ORA #$00 can't know if the previous
contents of the accumulator were nonzero, only that the instruction
hasn't made them nonzero, but instead of marking the Z-flag
"indeterminate" it was leaving the flag in its previous state.  This
produces incorrect results if the previous instruction didn't set
its flags from the accumulator contents, e.g. it was an LDX.

Test 1003-flags-and-branches has been updated to test these states.
2020-05-01 17:29:22 -07:00
Andy McFadden
59b7ec0dea Recognize that LSR always clears the 'N' flag
The instruction shifts 0 into the high bit, so the result is never
negative.  Added a test case to 1003-flags-and-branches.
2020-04-23 17:23:12 -07:00
Andy McFadden
5b75ae35fc Fix ANDImm flag updater
For nonzero values we were leaving Z=prev, which is wrong when Z=0
because the AND result might be zero.  Now if Z=1 we leave it alone,
but if Z=0 we now set it to Z=?.

Test 1003-flags-and-branches was testing for the (incorrect)
behavior, so we're now running into a BRK.  This is fine.
2020-02-01 16:41:44 -08:00
Andy McFadden
e79064709c Clarify BRK explanation 2019-10-29 10:18:48 -07:00
Andy McFadden
1b0ee7de21 Fix display of instruction attributes
The "affected flags" constants were incorrect for BIT, BRK, COP,
RTI, XCE, and the undocmented instructions ANE, DCP, and SAX.  The
constants are used for the changed-flag summary shown in the info
window and the instruction chart.

Of greater import: the status flag updater for BIT was incorrectly
marking N/V/C as indeterminate instead of N/V/Z.  The undocmented
instructions ANE, DCP, and SAX were also incorrect.

The cycle counts shown in line comments are computed correctly, but
the counts shown in the info window and instruction chart were
displaying the full set of modifiers, ignoring the CPU type.  That's
okay for the info window, which spells the modifiers out, though
it'd be better if the bits were explicitly marked as being applicable
to the current CPU or a different one.
2019-10-22 10:48:02 -07:00
Andy McFadden
716dce5f28 Pass operand to extension script JSR/JSL handlers
Sort of silly to have every handler immediately pull the operand out
of the file data.  (This is arguably less efficient, since we now
have to serialize the argument across the AppDomain boundary, but
we should be okay spending a few extra nanoseconds here.)
2019-10-17 13:15:25 -07:00
Andy McFadden
4d8ee3fd07 External symbol I/O direction and address mask, part 2
First cut at lookup-by-address implementation.  Seems to work, but
needs full tests.
2019-10-16 14:55:10 -07:00
Andy McFadden
9c3422623d External symbol I/O direction and address mask, part 1
Memory-mapped I/O locations can have different behavior when read
vs. written.  This is part 1 of a change to allow two different
symbols to represent the same address, based on I/O direction.

This also adds a set of address masks for systems like the Atari
2600 that map hardware addresses to multiple locations.

This change updates the data structures, .sym65 file reader,
project serialization, and DefSymbol editor.
2019-10-15 19:12:57 -07:00
Andy McFadden
dfd5bcab1b Optionally treat BRKs as two-byte instructions
Early data sheets listed BRK as one byte, but RTI after a BRK skips
the following byte, effectively making BRK a 2-byte instruction.
Sometimes, such as when diassembling Apple /// SOS code, it's handy
to treat it that way explicitly.

This change makes two-byte BRKs optional, controlled by a checkbox
in the project settings.  In the system definitions it defaults to
true for Apple ///, false for all others.

ACME doesn't allow BRK to have an arg, and cc65 only allows it for
65816 code (?), so it's emitted as a hex blob for those assemblers.
Anyone wishing to target those assemblers should stick to 1-byte mode.

Extension scripts have to switch between formatting one byte of
inline data and formatting an instruction with a one-byte operand.
A helper function has been added to the plugin Util class.

To get some regression test coverage, 2022-extension-scripts has
been configured to use two-byte BRK.

Also, added/corrected some SOS constants.

See also issue #44.
2019-10-09 14:55:56 -07:00
Andy McFadden
1ddf4bed48 Fix code tracing bug
If you set things up just right, it's possible for flag status
changes to fail to get merged.

Added a regression test to 1003-flags-and-branches.

Also, tweaked the instruction operand editor to be a bit smoother
from the keyboard: added alt-key shortcuts, and put the focus on the
OK button after creating/editing a label so you can just hit the
return key twice.
2019-09-17 14:38:16 -07:00
Andy McFadden
88e72d1eb8 Rename regression test 2020 to reflect the CPU configuration
Cycle counting is CPU-specific.  The 2020 test exercises the
65816, but there are things unique to 6502 and 65C02 that should
also be checked if we want to be thorough.

No changes to the test itself.
2019-09-15 17:02:21 -07:00
Andy McFadden
e8ae534879 Instruction operand editor rework, part 2
Implemented local variable editing.  Operands that have a local
variable reference, or are eligible to have one, can now be edited
directly from the instruction operand edit dialog.

Also, updated the code list double-click handler so that, if you
double-click on the opcode of an instruction that uses a local
variable reference, the selection and view will jump to the place
where that variable was defined.

Also, tweaked the way the References window refers to references
to an address that didn't use a symbol at that address.  Updated
the explanation in the manual, which was a bit confusing.

Also, fixed some odds and ends in the manual.

Also, fixed a nasty infinite recursion bug (issue #47).
2019-09-07 20:56:43 -07:00
Andy McFadden
6a2532588b Local variables mostly work
Variables are now handled properly end-to-end, except for label
uniquification.  So cc65 and ACME can't yet handle a file that
redefines a local variable.

This required a bunch of plumbing, but I think it came out okay.
2019-08-30 18:39:29 -07:00
Andy McFadden
0ed1547e79 Set Anattrib DataDescriptor for local variable references
We now generate FormatDescriptors with WeakSymbolRefs for direct
page references that match variable table entries.

LocalVariableTable got a rewrite.  We need to be unique in both
name and address, but for the address we have to take the width into
account as well.  We also want to sort the display by address
rather than name.  (Some people might want it sorted by name, but
we can worry about that some other time.)

Updated the DefSymbol editor to require value uniqueness.  Note
addresses and constants exist in separate namespaces.

The various symbols are added to the SymbolTable so that uniqueness
checks work correctly.  This also allows the operand generation to
appear to work, but it doesn't yet handle redefinition of symbols.
2019-08-28 18:01:38 -07:00
Andy McFadden
98914e9f80 Treat BRK as a 1-byte instruction
The 65816 definition makes it a two-byte instruction, like COP.  On
the 6502 it acted like a two-byte instruction, but in practice very
few assemblers treat it that way.  Very few humans, for that matter.
So it's now treated as a single byte instruction, with the following
byte encoded as a data value.
2019-08-02 17:21:50 -07:00
Andy McFadden
47b1363738 Add more detail to cross references
In the cross-reference table we now indicate whether the reference
source is doing a read, write, read-modify-write, branch, subroutine
call, is just referencing the address, or is part of the data.
2019-04-11 16:23:02 -07:00
Andy McFadden
a88c746419 Work around cc65 single-pass behavior
The cc65 assembler runs in a single pass, which means forward
address references default to 16 bits.  For zero-page references
we have to add an explicit width disambiguator.  (This is an
unusual situation that only occurs if you have a zero-page .ORG
in the file after code that references it.)

With this change, 2014-label-dp passes, and no other regression
tests were affected.

(issue #40)
2018-11-02 15:32:54 -07:00
Andy McFadden
fd6d8273a9 Add custom flag updaters for ROL/ROR
There are some useful interactions between C/N and maybe Z.  Added
a quick test to 1003-flags-and-branches.

Also, updated the 2008-address-changes tests.  Change b37d3dba
extended the nearby-target range of out-of-file symbols by one, so
one line that didn't get an operand label now does.
2018-10-09 13:15:41 -07:00
Andy McFadden
a23c7e5ab6 Rename undocumented 6502 opcodes to match Unintended Opcodes doc
These *almost* match what cc65 has, and are accepted as primary or
aliases by 64tass.

This combines the LAX and LXA operations.  LXA is the immediate
form of LAX, and behaves somewhat differently (and is unstable).
I was treating them as two separate operations with independent
mnemonics, but that doesn't seem to be the preferred way to
handle it.

The cc65 generator wasn't generating LAX before; now it does.  This
required nudging the width disambiguator, as LAX is a second
example of an instruction with both DP,Y and ABS,Y operands.

(issue #20)
2018-10-05 14:28:45 -07:00
Andy McFadden
2c6212404d Initial file commit 2018-09-28 10:05:11 -07:00