trig_tables.h

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#ifndef TRIG_TABLES_H
#define TRIG_TABLES_H
 
/*
 * The sine and cosine tables overlap, but "#define gCosineTable (gSineTable +
 * 0x400)" doesn't give expected codegen; gSineTable and gCosineTable need to
 * be different symbols for code to match. Most likely the tables were placed
 * adjacent to each other, and gSineTable cut short, such that reads overflow
 * into gCosineTable.
 *
 * These kinds of out of bounds reads are undefined behavior, and break on
 * e.g. GCC (which doesn't place the tables next to each other, and probably
 * exploits array sizes for range analysis-based optimizations as well).
 * Thus, for non-IDO compilers we use the standard-compliant version.
 */
extern f32 gSineTable[];
#ifdef AVOID_UB
#define gCosineTable (gSineTable + 0x400)
#else
extern f32 gCosineTable[];
#endif
 
extern s16 gArctanTable[];
 
#endif