From 0d8cae5a531faa7c08387d3c3d75b4009f7bb693 Mon Sep 17 00:00:00 2001
From: XProger <xproger@list.ru>
Date: Mon, 28 Nov 2022 03:36:37 +0300
Subject: [PATCH] #368 GBA sound buffer switch optimization (one MUL, minor)

---
 src/platform/gba/asm/sndPCM.s | 2 +-
 src/platform/gba/main.cpp     | 6 +++---
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/platform/gba/asm/sndPCM.s b/src/platform/gba/asm/sndPCM.s
index 83bfdf5..1c2d435 100644
--- a/src/platform/gba/asm/sndPCM.s
+++ b/src/platform/gba/asm/sndPCM.s
@@ -19,7 +19,7 @@ tmp     .req ampA
 .macro clamp amp
     // Vanadium's clamp trick (-128..127)
     mov tmp, \amp, asr #31  // tmp <- 0xffffffff
-    cmp tmp, \amp, asr #7  // not equal
+    cmp tmp, \amp, asr #7   // not equal
     eorne \amp, tmp, #0x7F  // amp <- 0xffffff80
 .endm
 
diff --git a/src/platform/gba/main.cpp b/src/platform/gba/main.cpp
index 932d457..9c5102c 100644
--- a/src/platform/gba/main.cpp
+++ b/src/platform/gba/main.cpp
@@ -497,14 +497,14 @@ void soundInit()
 
 void soundFill()
 {
-    if (curSoundBuffer == 1) {
+    if (curSoundBuffer) {
         REG_DMA1CNT = 0;
         REG_DMA1SAD = (u32)soundBuffer;
         REG_DMA1CNT = DMA_DST_FIXED | DMA_REPEAT | DMA_16 | DMA_AT_FIFO | DMA_ENABLE;
     }
 
-    sndFill(soundBuffer + curSoundBuffer * SND_SAMPLES, SND_SAMPLES);
-    curSoundBuffer ^= 1;
+    sndFill(soundBuffer + curSoundBuffer, SND_SAMPLES);
+    curSoundBuffer ^= SND_SAMPLES;
 }
 
 void vblank()