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NDS : Micro-optimizations for the software blitter

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svn-id: r24804
This commit is contained in:
Bertrand Augereau 2006-12-03 16:09:26 +00:00
parent 352ed7299f
commit 0b110b42da
1 changed files with 26 additions and 9 deletions
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35
backends/platform/ds/arm9/source/blitters.cpp
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@ -143,28 +143,45 @@ static inline void RescaleBlock_5x1555_To_4x1555( u16 s0, u16 s1, u16 s2, u16 s3
u32 bs2 = s2 & 0x1F;
u32 bs3 = s3 & 0x1F;
u32 bs4 = s4 & 0x1F;
u32 gs0_4 = (s0 >> 3) & 0x7C;
#if 0
u32 gs0 = (s0 >> 5) & 0x1F;
u32 gs1 = (s1 >> 5) & 0x1F;
u32 gs2 = (s2 >> 5) & 0x1F;
u32 gs3 = (s3 >> 5) & 0x1F;
u32 gs4_4 = (s4 >> 3) & 0x7C;
u32 gs4 = (s4 >> 5) & 0x1F;
u32 rs0_4 = (s0 >> 8) & 0x7C;
u32 rs0 = (s0 >> 10) & 0x1F;
u32 rs1 = (s1 >> 10) & 0x1F;
u32 rs2 = (s2 >> 10) & 0x1F;
u32 rs3 = (s3 >> 10) & 0x1F;
u32 rs4_4 = (s4 >> 8) & 0x7C;
u32 rs4 = (s4 >> 10) & 0x1F;
#else
// The compiler absolutely wants to use 0x1F as an immediate, which makes it unable to fold the shift during the and
u32 mask = 0x1F;
u32 gs0, gs1, gs2, gs3, gs4;
asm("and %0, %2, %1, lsr #5" : "=r"(gs0) : "r"(s0), "r"(mask) : );
asm("and %0, %2, %1, lsr #5" : "=r"(gs1) : "r"(s1), "r"(mask) : );
asm("and %0, %2, %1, lsr #5" : "=r"(gs2) : "r"(s2), "r"(mask) : );
asm("and %0, %2, %1, lsr #5" : "=r"(gs3) : "r"(s3), "r"(mask) : );
asm("and %0, %2, %1, lsr #5" : "=r"(gs4) : "r"(s4), "r"(mask) : );
u32 rs0, rs1, rs2, rs3, rs4;
asm("and %0, %2, %1, lsr #10" : "=r"(rs0) : "r"(s0), "r"(mask) : );
asm("and %0, %2, %1, lsr #10" : "=r"(rs1) : "r"(s1), "r"(mask) : );
asm("and %0, %2, %1, lsr #10" : "=r"(rs2) : "r"(s2), "r"(mask) : );
asm("and %0, %2, %1, lsr #10" : "=r"(rs3) : "r"(s3), "r"(mask) : );
asm("and %0, %2, %1, lsr #10" : "=r"(rs4) : "r"(s4), "r"(mask) : );
#endif
u32 rd0 = rs0_4 + rs1;
u32 rd0 = 4*rs0 + rs1;
u32 rd1 = 2*rs1 + rs1 + 2*rs2;
u32 rd2 = 2*rs2 + 2*rs3 + rs3;
u32 rd3 = rs3 + rs4_4;
u32 rd3 = rs3 + 4*rs4;
u32 gd0 = gs0_4 + gs1;
u32 gd0 = 4*gs0 + gs1;
u32 gd1 = 2*gs1 + gs1 + 2*gs2;
u32 gd2 = 2*gs2 + 2*gs3 + gs3;
u32 gd3 = gs3 + gs4_4;
u32 gd3 = gs3 + 4*gs4;
u32 bd0 = 4*bs0 + bs1;
u32 bd1 = 2*bs1 + bs1 + 2*bs2;