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NEON/TransformWHT: avoid q4-q7 registers

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very tiny speed improvement

Change-Id: Iace78b9038af412d0a794845ff19f54afa88ccdc
This commit is contained in:
James Zern 2013-09-06 20:22:00 -04:00
parent 4df0c89e24
commit 2f09d63e30
1 changed files with 24 additions and 24 deletions
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48
src/dsp/dec_neon.c
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@ -324,39 +324,39 @@ static void TransformWHT(const int16_t* in, int16_t* out) {
// load data into q0, q1
"vld1.16 {q0, q1}, [%[in]] \n"
"vaddl.s16 q2, d0, d3 \n" // a0 = in[0] + in[12]
"vaddl.s16 q3, d1, d2 \n" // a1 = in[4] + in[8]
"vsubl.s16 q4, d1, d2 \n" // a2 = in[4] - in[8]
"vsubl.s16 q5, d0, d3 \n" // a3 = in[0] - in[12]
"vaddl.s16 q2, d0, d3 \n" // a0 = in[0] + in[12]
"vaddl.s16 q3, d1, d2 \n" // a1 = in[4] + in[8]
"vsubl.s16 q10, d1, d2 \n" // a2 = in[4] - in[8]
"vsubl.s16 q11, d0, d3 \n" // a3 = in[0] - in[12]
"vadd.s32 q0, q2, q3 \n" // tmp[0] = a0 + a1
"vsub.s32 q2, q2, q3 \n" // tmp[8] = a0 - a1
"vadd.s32 q1, q5, q4 \n" // tmp[4] = a3 + a2
"vsub.s32 q3, q5, q4 \n" // tmp[12] = a3 - a2
"vadd.s32 q0, q2, q3 \n" // tmp[0] = a0 + a1
"vsub.s32 q2, q2, q3 \n" // tmp[8] = a0 - a1
"vadd.s32 q1, q11, q10 \n" // tmp[4] = a3 + a2
"vsub.s32 q3, q11, q10 \n" // tmp[12] = a3 - a2
// Transpose
// q0 = tmp[0, 4, 8, 12], q1 = tmp[2, 6, 10, 14]
// q2 = tmp[1, 5, 9, 13], q3 = tmp[3, 7, 11, 15]
"vswp d1, d4 \n" // vtrn.64 q0, q2
"vswp d3, d6 \n" // vtrn.64 q1, q3
"vswp d1, d4 \n" // vtrn.64 q0, q2
"vswp d3, d6 \n" // vtrn.64 q1, q3
"vtrn.32 q0, q1 \n"
"vtrn.32 q2, q3 \n"
"vmov.s32 q4, #3 \n" // dc = 3
"vadd.s32 q0, q0, q4 \n" // dc = tmp[0] + 3
"vadd.s32 q6, q0, q3 \n" // a0 = dc + tmp[3]
"vadd.s32 q7, q1, q2 \n" // a1 = tmp[1] + tmp[2]
"vsub.s32 q8, q1, q2 \n" // a2 = tmp[1] - tmp[2]
"vsub.s32 q9, q0, q3 \n" // a3 = dc - tmp[3]
"vmov.s32 q10, #3 \n" // dc = 3
"vadd.s32 q0, q0, q10 \n" // dc = tmp[0] + 3
"vadd.s32 q12, q0, q3 \n" // a0 = dc + tmp[3]
"vadd.s32 q13, q1, q2 \n" // a1 = tmp[1] + tmp[2]
"vsub.s32 q8, q1, q2 \n" // a2 = tmp[1] - tmp[2]
"vsub.s32 q9, q0, q3 \n" // a3 = dc - tmp[3]
"vadd.s32 q0, q6, q7 \n"
"vshrn.s32 d0, q0, #3 \n" // (a0 + a1) >> 3
"vadd.s32 q0, q12, q13 \n"
"vshrn.s32 d0, q0, #3 \n" // (a0 + a1) >> 3
"vadd.s32 q1, q9, q8 \n"
"vshrn.s32 d1, q1, #3 \n" // (a3 + a2) >> 3
"vsub.s32 q2, q6, q7 \n"
"vshrn.s32 d2, q2, #3 \n" // (a0 - a1) >> 3
"vshrn.s32 d1, q1, #3 \n" // (a3 + a2) >> 3
"vsub.s32 q2, q12, q13 \n"
"vshrn.s32 d2, q2, #3 \n" // (a0 - a1) >> 3
"vsub.s32 q3, q9, q8 \n"
"vshrn.s32 d3, q3, #3 \n" // (a3 - a2) >> 3
"vshrn.s32 d3, q3, #3 \n" // (a3 - a2) >> 3
// set the results to output
"vst1.16 d0[0], [%[out]], %[kStep] \n"
@ -378,8 +378,8 @@ static void TransformWHT(const int16_t* in, int16_t* out) {
: [out] "+r"(out) // modified registers
: [in] "r"(in), [kStep] "r"(kStep) // constants
: "memory", "q0", "q1", "q2", "q3", "q4",
"q5", "q6", "q7", "q8", "q9" // clobbered
: "memory", "q0", "q1", "q2", "q3",
"q8", "q9", "q10", "q11", "q12", "q13" // clobbered
);
}