From 3284a18ad35fc9d47cb62c902667bd582962f688 Mon Sep 17 00:00:00 2001
From: PugsyMAME <pugsy@gmx.net>
Date: Tue, 29 Dec 2020 14:55:49 +0000
Subject: [PATCH] Add new Cheat Type F4, Find & Replace Bytes (#1345)
* Add new Cheat Type F4, Find & Replace Bytes
Also knows as 'AOB' apparently. Information about how it works will be in the next chtdb.txt header or you can read/ask about it on the discord channel.
* Add new Cheat Type F4, Find & Replace Bytes
Also knows as 'AOB' apparently. Information about how it works will be in the next chtdb.txt header or you can read/ask about it on the discord channel.
* Added error trapping for cheat type F4
As suggested
---
src/core/cheats.cpp | 96 ++++++++++++++++++++++++++++++++++++++++++++-
src/core/cheats.h | 1 +
2 files changed, 96 insertions(+), 1 deletion(-)
diff --git a/src/core/cheats.cpp b/src/core/cheats.cpp
index bf83b5386..63cdb624e 100644
--- a/src/core/cheats.cpp
+++ b/src/core/cheats.cpp
@@ -1213,6 +1213,98 @@ void CheatCode::Apply() const
index += 2;
}
break;
+
+ case InstructionCode::ExtFindAndReplace:
+ {
+
+ if ((index + 4) >= instructions.size())
+ {
+ Log_ErrorPrintf("Incomplete find/replace instruction");
+ return;
+ }
+ const Instruction& inst2 = instructions[index + 1];
+ const Instruction& inst3 = instructions[index + 2];
+ const Instruction& inst4 = instructions[index + 3];
+ const Instruction& inst5 = instructions[index + 4];
+
+ const u32 offset = Truncate16(inst.value32 & 0x0000FFFFu) << 1;
+ const u8 wildcard = Truncate8((inst.value32 & 0x00FF0000u) >> 16);
+ const u32 minaddress = inst.address - offset;
+ const u32 maxaddress = inst.address + offset;
+ const u8 f1 = Truncate8((inst2.first & 0xFF000000u) >> 24);
+ const u8 f2 = Truncate8((inst2.first & 0x00FF0000u) >> 16);
+ const u8 f3 = Truncate8((inst2.first & 0x0000FF00u) >> 8);
+ const u8 f4 = Truncate8 (inst2.first & 0x000000FFu);
+ const u8 f5 = Truncate8((inst2.value32 & 0xFF000000u) >> 24);
+ const u8 f6 = Truncate8((inst2.value32 & 0x00FF0000u) >> 16);
+ const u8 f7 = Truncate8((inst2.value32 & 0x0000FF00u) >> 8);
+ const u8 f8 = Truncate8 (inst2.value32 & 0x000000FFu);
+ const u8 f9 = Truncate8((inst3.first & 0xFF000000u) >> 24);
+ const u8 f10 = Truncate8((inst3.first & 0x00FF0000u) >> 16);
+ const u8 f11 = Truncate8((inst3.first & 0x0000FF00u) >> 8);
+ const u8 f12 = Truncate8 (inst3.first & 0x000000FFu);
+ const u8 f13 = Truncate8((inst3.value32 & 0xFF000000u) >> 24);
+ const u8 f14 = Truncate8((inst3.value32 & 0x00FF0000u) >> 16);
+ const u8 f15 = Truncate8((inst3.value32 & 0x0000FF00u) >> 8);
+ const u8 f16 = Truncate8 (inst3.value32 & 0x000000FFu);
+ const u8 r1 = Truncate8((inst4.first & 0xFF000000u) >> 24);
+ const u8 r2 = Truncate8((inst4.first & 0x00FF0000u) >> 16);
+ const u8 r3 = Truncate8((inst4.first & 0x0000FF00u) >> 8);
+ const u8 r4 = Truncate8 (inst4.first & 0x000000FFu);
+ const u8 r5 = Truncate8((inst4.value32 & 0xFF000000u) >> 24);
+ const u8 r6 = Truncate8((inst4.value32 & 0x00FF0000u) >> 16);
+ const u8 r7 = Truncate8((inst4.value32 & 0x0000FF00u) >> 8);
+ const u8 r8 = Truncate8 (inst4.value32 & 0x000000FFu);
+ const u8 r9 = Truncate8((inst5.first & 0xFF000000u) >> 24);
+ const u8 r10 = Truncate8((inst5.first & 0x00FF0000u) >> 16);
+ const u8 r11 = Truncate8((inst5.first & 0x0000FF00u) >> 8);
+ const u8 r12 = Truncate8 (inst5.first & 0x000000FFu);
+ const u8 r13 = Truncate8((inst5.value32 & 0xFF000000u) >> 24);
+ const u8 r14 = Truncate8((inst5.value32 & 0x00FF0000u) >> 16);
+ const u8 r15 = Truncate8((inst5.value32 & 0x0000FF00u) >> 8);
+ const u8 r16 = Truncate8 (inst5.value32 & 0x000000FFu);
+
+ for (u32 address = minaddress;address<=maxaddress;address+=2)
+ {
+ if ((DoMemoryRead<u8>(address )==f1 || f1 == wildcard) &&
+ (DoMemoryRead<u8>(address+1 )==f2 || f2 == wildcard) &&
+ (DoMemoryRead<u8>(address+2 )==f3 || f3 == wildcard) &&
+ (DoMemoryRead<u8>(address+3 )==f4 || f4 == wildcard) &&
+ (DoMemoryRead<u8>(address+4 )==f5 || f5 == wildcard) &&
+ (DoMemoryRead<u8>(address+5 )==f6 || f6 == wildcard) &&
+ (DoMemoryRead<u8>(address+6 )==f7 || f7 == wildcard) &&
+ (DoMemoryRead<u8>(address+7 )==f8 || f8 == wildcard) &&
+ (DoMemoryRead<u8>(address+8 )==f9 || f9 == wildcard) &&
+ (DoMemoryRead<u8>(address+9 )==f10|| f10 == wildcard) &&
+ (DoMemoryRead<u8>(address+10)==f11|| f11 == wildcard) &&
+ (DoMemoryRead<u8>(address+11)==f12|| f12 == wildcard) &&
+ (DoMemoryRead<u8>(address+12)==f13|| f13 == wildcard) &&
+ (DoMemoryRead<u8>(address+13)==f14|| f14 == wildcard) &&
+ (DoMemoryRead<u8>(address+14)==f15|| f15 == wildcard) &&
+ (DoMemoryRead<u8>(address+15)==f16|| f16 == wildcard))
+ {
+ if (r1 != wildcard) DoMemoryWrite<u8>(address , r1 );
+ if (r2 != wildcard) DoMemoryWrite<u8>(address+1 , r2 );
+ if (r3 != wildcard) DoMemoryWrite<u8>(address+2 , r3 );
+ if (r4 != wildcard) DoMemoryWrite<u8>(address+3 , r4 );
+ if (r5 != wildcard) DoMemoryWrite<u8>(address+4 , r5 );
+ if (r6 != wildcard) DoMemoryWrite<u8>(address+5 , r6 );
+ if (r7 != wildcard) DoMemoryWrite<u8>(address+6 , r7 );
+ if (r8 != wildcard) DoMemoryWrite<u8>(address+7 , r8 );
+ if (r9 != wildcard) DoMemoryWrite<u8>(address+8 , r9 );
+ if (r10 != wildcard) DoMemoryWrite<u8>(address+9 , r10);
+ if (r11 != wildcard) DoMemoryWrite<u8>(address+10, r11);
+ if (r12 != wildcard) DoMemoryWrite<u8>(address+11, r12);
+ if (r13 != wildcard) DoMemoryWrite<u8>(address+12, r13);
+ if (r14 != wildcard) DoMemoryWrite<u8>(address+13, r14);
+ if (r15 != wildcard) DoMemoryWrite<u8>(address+14, r15);
+ if (r16 != wildcard) DoMemoryWrite<u8>(address+15, r16);
+ address=address+15;
+ }
+ }
+ index += 5;
+ }
+ break;
case InstructionCode::CompareEqual16:
{
@@ -1479,7 +1571,9 @@ void CheatCode::ApplyOnDisable() const
case InstructionCode::MemoryCopy:
index += 2;
break;
-
+ case InstructionCode::ExtFindAndReplace:
+ index += 5;
+ break;
// for conditionals, we don't want to skip over in case it changed at some point
case InstructionCode::ExtCompareEqual32:
case InstructionCode::ExtCompareNotEqual32:
diff --git a/src/core/cheats.h b/src/core/cheats.h
index e3e11012f..805a155d2 100644
--- a/src/core/cheats.h
+++ b/src/core/cheats.h
@@ -62,6 +62,7 @@ struct CheatCode
ExtConstantForceRangeLimits16 = 0xF1,
ExtConstantForceRangeRollRound16 = 0xF2,
ExtConstantForceRange16 = 0xF3,
+ ExtFindAndReplace = 0xF4,
ExtConstantBitSet8 = 0x31,
ExtConstantBitClear8 = 0x32,
ExtConstantBitSet16 = 0x81,