Remove gSystemHeap and use _buffersSegmentEnd instead, make buffer alignments explicit for gcc (#1901)

* Remove gSystemHeap and use _buffersSegmentEnd instead, make buffer alignments explicit for gcc

* ALIGNEDn -> ALIGNED(n), reposition alignment attribute for PreNmiBuff

* Correct positioning of ALIGNED for filter data in audio/lib/data.c

* Add ALIGNED to TypenameMacros

* ALIGNED(4) on same line for PreNmiBuff

* Revert audio load.c change, to be submitted separately

src/buffers/audio_heap.c

@@ -0,0 +1,3 @@
+#include "z64.h"
+
+ALIGNED(16) u8 gAudioHeap[0x38000];

src/buffers/gfxbuffers.c

@@ -1,13 +1,9 @@
 #include "z64.h"
 
-// 0x18000 bytes
-u64 gGfxSPTaskOutputBuffer[0x3000];
+ALIGNED(16) u64 gGfxSPTaskOutputBuffer[0x3000];
 
-// 0xC00 bytes
-u64 gGfxSPTaskYieldBuffer[OS_YIELD_DATA_SIZE / sizeof(u64)];
+ALIGNED(16) u64 gGfxSPTaskYieldBuffer[OS_YIELD_DATA_SIZE / sizeof(u64)];
 
-// 0x400 bytes
-u64 gGfxSPTaskStack[SP_DRAM_STACK_SIZE64];
+ALIGNED(16) u64 gGfxSPTaskStack[SP_DRAM_STACK_SIZE64];
 
-// 0x12410 bytes each; 0x24820 bytes total
-GfxPool gGfxPools[2];
+ALIGNED(16) GfxPool gGfxPools[2];

src/buffers/heaps.c

@@ -1,6 +0,0 @@
-#include "z64.h"
-
-// 0x38000 bytes
-u8 gAudioHeap[0x38000];
-
-u8 gSystemHeap[UNK_SIZE];

src/buffers/zbuffer.c

@@ -1,4 +1,3 @@
 #include "z64.h"
 
-// 0x25800 bytes
-u16 gZBuffer[SCREEN_HEIGHT][SCREEN_WIDTH];
+ALIGNED(64) u16 gZBuffer[SCREEN_HEIGHT][SCREEN_WIDTH];