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author Olivier Galibert <galibert@pobox.com>2017-07-05 11:44:49 +0200
committer Olivier Galibert <galibert@pobox.com>2017-11-26 17:41:27 +0100
commit6caef2579a1490f05d28bcede731cbdd45fc5c65 (patch)
tree8055384e183be3cb27e7d0894ac53dc96c09e6fa /src/devices/cpu/m6502/m6502d.cpp
parent34b222062c89adbeed822f56be6130421777e11f (diff)
dvdisasm: Overhaul [O. Galibert]
Disassemblers are now independant classes. Not only the code is cleaner, but unidasm has access to all the cpu cores again. The interface to the disassembly method has changed from byte buffers to objects that give a result to read methods. This also adds support for lfsr and/or paged PCs.
Diffstat (limited to 'src/devices/cpu/m6502/m6502d.cpp')
-rw-r--r--src/devices/cpu/m6502/m6502d.cpp192
1 files changed, 192 insertions, 0 deletions
diff --git a/src/devices/cpu/m6502/m6502d.cpp b/src/devices/cpu/m6502/m6502d.cpp
new file mode 100644
index 00000000000..8b8918e5ccf
--- /dev/null
+++ b/src/devices/cpu/m6502/m6502d.cpp
@@ -0,0 +1,192 @@
+// license:BSD-3-Clause
+// copyright-holders:Olivier Galibert
+/***************************************************************************
+
+ m6502d.cpp
+
+ Mostek 6502, original NMOS variant, disassembler
+
+***************************************************************************/
+
+#include "m6502d.h"
+#include "cpu/m6502/m6502d.hxx"
+
+m6502_base_disassembler::m6502_base_disassembler(const disasm_entry *_table) : table(_table)
+{
+}
+
+u32 m6502_base_disassembler::get_instruction_bank() const
+{
+ return 0;
+}
+
+u32 m6502_base_disassembler::opcode_alignment() const
+{
+ return 1;
+}
+
+offs_t m6502_base_disassembler::disassemble(std::ostream &stream, offs_t pc, const data_buffer &opcodes, const data_buffer &params)
+{
+ const disasm_entry &e = table[opcodes.r8(pc) | get_instruction_bank()];
+ uint32_t flags = e.flags | SUPPORTED;
+ util::stream_format(stream, "%s", e.opcode);
+
+ switch(e.mode) {
+ case DASM_non:
+ flags |= 1;
+ break;
+
+ case DASM_aba:
+ util::stream_format(stream, " $%02x%02x", params.r8(pc+2), params.r8(pc+1));
+ flags |= 3;
+ break;
+
+ case DASM_abx:
+ util::stream_format(stream, " $%02x%02x, x", params.r8(pc+2), params.r8(pc+1));
+ flags |= 3;
+ break;
+
+ case DASM_aby:
+ util::stream_format(stream, " $%02x%02x, y", params.r8(pc+2), params.r8(pc+1));
+ flags |= 3;
+ break;
+
+ case DASM_acc:
+ util::stream_format(stream, " a");
+ flags |= 1;
+ break;
+
+ case DASM_adr:
+ util::stream_format(stream, " $%02x%02x", params.r8(pc+2), params.r8(pc+1));
+ flags |= 3;
+ break;
+
+ case DASM_bzp:
+ util::stream_format(stream, "%d $%02x", (opcodes.r8(pc) >> 4) & 7, params.r8(pc+1));
+ flags |= 2;
+ break;
+
+ case DASM_iax:
+ util::stream_format(stream, " ($%02x%02x, x)", params.r8(pc+2), params.r8(pc+1));
+ flags |= 3;
+ break;
+
+ case DASM_idx:
+ util::stream_format(stream, " ($%02x, x)", params.r8(pc+1));
+ flags |= 2;
+ break;
+
+ case DASM_idy:
+ util::stream_format(stream, " ($%02x), y", params.r8(pc+1));
+ flags |= 2;
+ break;
+
+ case DASM_idz:
+ util::stream_format(stream, " ($%02x), z", params.r8(pc+1));
+ flags |= 2;
+ break;
+
+ case DASM_imm:
+ util::stream_format(stream, " #$%02x", params.r8(pc+1));
+ flags |= 2;
+ break;
+
+ case DASM_imp:
+ flags |= 1;
+ break;
+
+ case DASM_ind:
+ util::stream_format(stream, " ($%02x%02x)", params.r8(pc+2), params.r8(pc+1));
+ flags |= 3;
+ break;
+
+ case DASM_isy:
+ util::stream_format(stream, " ($%02x, s), y", params.r8(pc+1));
+ flags |= 2;
+ break;
+
+ case DASM_iw2:
+ util::stream_format(stream, " #$%02x%02x", params.r8(pc+2), params.r8(pc+1));
+ flags |= 3;
+ break;
+
+ case DASM_iw3:
+ util::stream_format(stream, " #$%02x%02x%02x", params.r8(pc+3), params.r8(pc+2), params.r8(pc+1));
+ flags |= 4;
+ break;
+
+ case DASM_rel:
+ util::stream_format(stream, " $%04x", (pc & 0xf0000) | uint16_t(pc + 2 + int8_t(params.r8(pc+1))));
+ flags |= 2;
+ break;
+
+ case DASM_rw2:
+ util::stream_format(stream, " $%04x", (pc & 0xf0000) | uint16_t(pc + 2 + int16_t((params.r8(pc+2) << 8) | params.r8(pc+1))));
+ flags |= 3;
+ break;
+
+ case DASM_zpb:
+ util::stream_format(stream, "%d $%02x, $%04x", (opcodes.r8(pc) >> 4) & 7, params.r8(pc+1), (pc & 0xf0000) | uint16_t(pc + 3 + int8_t(params.r8(pc+2))));
+ flags |= 3;
+ break;
+
+ case DASM_zpg:
+ util::stream_format(stream, " $%02x", params.r8(pc+1));
+ flags |= 2;
+ break;
+
+ case DASM_zpi:
+ util::stream_format(stream, " ($%02x)", params.r8(pc+1));
+ flags |= 2;
+ break;
+
+ case DASM_zpx:
+ util::stream_format(stream, " $%02x, x", params.r8(pc+1));
+ flags |= 2;
+ break;
+
+ case DASM_zpy:
+ util::stream_format(stream, " $%02x, y", params.r8(pc+1));
+ flags |= 2;
+ break;
+
+ case DASM_imz:
+ util::stream_format(stream, " #$%02x, $%02x", params.r8(pc+1), params.r8(pc+2));
+ flags |= 3;
+ break;
+
+ case DASM_spg:
+ util::stream_format(stream, " \\$%02x", params.r8(pc+1));
+ flags |= 2;
+ break;
+
+ case DASM_biz:
+ util::stream_format(stream, " %d, $%02x", (opcodes.r8(pc) >> 5) & 7, params.r8(pc+1));
+ flags |= 2;
+ break;
+
+ case DASM_bzr:
+ util::stream_format(stream, " %d, $%02x, $%04x", (opcodes.r8(pc) >> 5) & 7, params.r8(pc+1), (pc & 0xf0000) | uint16_t(pc + 3 + int8_t(params.r8(pc+2))));
+ flags |= 3;
+ break;
+
+ case DASM_bar:
+ util::stream_format(stream, " %d, a, $%04x", (opcodes.r8(pc) >> 5) & 7, (pc & 0xf0000) | uint16_t(pc + 3 + int8_t(params.r8(pc+1))));
+ flags |= 2;
+ break;
+
+ case DASM_bac:
+ util::stream_format(stream, " %d, a", (opcodes.r8(pc) >> 5) & 7);
+ flags |= 1;
+ break;
+
+ default:
+ fprintf(stderr, "Unhandled dasm mode %d\n", e.mode);
+ abort();
+ }
+ return flags;
+}
+
+m6502_disassembler::m6502_disassembler() : m6502_base_disassembler(disasm_entries)
+{
+}