From 0c0bc7c9e2b76eb7790182170e4bd32662347cc2 Mon Sep 17 00:00:00 2001
From: PJB3005 <pieterjan.briers+git@gmail.com>
Date: Sat, 25 Jul 2026 15:49:49 +0200
Subject: [PATCH] Compile out unused fields in DSP TChannel definition

---
 .../include/JSystem/JAudio2/JASDSPInterface.h   | 17 +++++++++++++++++
 libs/JSystem/src/JAudio2/JASDSPInterface.cpp    |  6 ++++++
 2 files changed, 23 insertions(+)

diff --git a/libs/JSystem/include/JSystem/JAudio2/JASDSPInterface.h b/libs/JSystem/include/JSystem/JAudio2/JASDSPInterface.h
index 7f830b6469..c45b72f2d8 100644
--- a/libs/JSystem/include/JSystem/JAudio2/JASDSPInterface.h
+++ b/libs/JSystem/include/JSystem/JAudio2/JASDSPInterface.h
@@ -109,7 +109,9 @@ namespace JASDsp {
          * Pitch shift via changing playback speed.
          */
         /* 0x004 */ u16 mPitch;
+#if !TARGET_PC
         /* 0x006 */ short _unused1;
+#endif
 
         /**
          * Set to 1 when playback starts, cleared by DSP later,
@@ -118,19 +120,27 @@ namespace JASDsp {
          * (Corroborated by fields JASAramStream checks never being cleared explicitly by CPU.)
          */
         /* 0x008 */ u16 mResetFlag;
+#if !TARGET_PC
         /* 0x00A */ u8 _unused2[0x00C - 0x00A];
+#endif
         /* 0x00C */ s16 mPauseFlag;
+#if !TARGET_PC
         /* 0x00E */ short _unused3;
+#endif
         /* 0x010 */ OutputChannelConfig mOutputChannels[DSP_OUTPUT_CHANNELS];
+#if !TARGET_PC
         /* 0x040 */ u8 _unused4[0x050 - 0x040];
+#endif
         /* 0x050 */ u16 mAutoMixerPanDolby; // pan is upper 8 bits, dolby lower 8.
         /* 0x052 */ u16 mAutoMixerFxMix;
         /* 0x054 */ u16 mAutoMixerInitVolume;
         /* 0x056 */ u16 mAutoMixerVolume;
         /* 0x058 */ u16 mAutoMixerBeenSet;
+#if !TARGET_PC
         /* 0x05A */ u8 _unused5[0x060 - 0x05A];
         /* 0x060 */ short field_0x060; // Only cleared to zero, presumed used by DSP.
         /* 0x062 */ u8 _unused6[0x064 - 0x062];
+#endif
 
         /**
          * Samples per ADPCM frame for ADPCM audio. Seems just set to 1 for PCM formats.
@@ -139,7 +149,9 @@ namespace JASDsp {
         /* 0x064 */ u16 mSamplesPerBlock;
         /* 0x066 */ short field_0x066; // Only cleared to zero, presumed used by DSP.
         /* 0x068 */ u32 mSamplePosition; // Only ever initialized by code, name is guess.
+#if !TARGET_PC
         /* 0x06C */ u8 _unused7[0x070 - 0x06C];
+#endif
 
         /**
          * Current audio read position in ARAM. Updated by DSP.
@@ -151,11 +163,13 @@ namespace JASDsp {
          * Gets written by DSP, but also CPU.
          */
         /* 0x074 */ u32 mSamplesLeft;      // Never directly cleared to zero. Seems sus. Cleared by DSP?
+#if !TARGET_PC
         /* 0x078 */ short field_0x078[4];  // Only cleared to zero, presumed used by DSP.
         /* 0x080 */ short field_0x080[20]; // Only cleared to zero, presumed used by DSP.
         /* 0x0A8 */ short field_0x0a8[4];  // Only cleared to zero, presumed used by DSP.
         /* 0x0B0 */ u16 field_0x0b0[16];   // Only cleared to zero, presumed used by DSP.
         /* 0x0D0 */ u8 _unused8[0x100 - 0x0D0];
+#endif
         /* 0x100 */ u16 mBytesPerBlock;
         /* 0x102 */ u16 mLoopFlag;
 
@@ -176,8 +190,11 @@ namespace JASDsp {
         /* 0x118 */ u32 mWaveAramAddress;
         /* 0x11C */ int mSampleCount;
         /* 0x120 */ s16 fir_filter_params[8];
+#if !TARGET_PC
         /* 0x130 */ u8 _unused9[0x148 - 0x130];
+#endif
         /* 0x148 */ s16 iir_filter_params[8];
+#if !TARGET_PC
         /* 0x158 */ u8 _unused10[0x180 - 0x158];
 #endif
 
diff --git a/libs/JSystem/src/JAudio2/JASDSPInterface.cpp b/libs/JSystem/src/JAudio2/JASDSPInterface.cpp
index 554660f6dc..04bec5dcc7 100644
--- a/libs/JSystem/src/JAudio2/JASDSPInterface.cpp
+++ b/libs/JSystem/src/JAudio2/JASDSPInterface.cpp
@@ -523,9 +523,12 @@ void JASDsp::TChannel::init() {
 void JASDsp::TChannel::playStart() {
     JUT_ASSERT(508, dspMutex);
     field_0x10c = 0;
+#if !TARGET_PC
     field_0x060 = 0;
+#endif
     mResetFlag = 1;
     field_0x066 = 0;
+#if !TARGET_PC
     int i;
     for (i = 0; i < 4; i++) {
         field_0x078[i] = 0;
@@ -534,6 +537,7 @@ void JASDsp::TChannel::playStart() {
     for (i = 0; i < 20; i++) {
         field_0x080[i] = 0;
     }
+#endif
     mIsActive = 1;
 }
 
@@ -601,9 +605,11 @@ void JASDsp::TChannel::setWaveInfo(JASWaveInfo const& waveInfo, u32 aramAddress,
                 break;
             }
         }
+#if !TARGET_PC
         for (i = 0; i < 16; i++) {
             field_0x0b0[i] = 0;
         }
+#endif
     }
 }