diff options
| author | Sv. Lockal <lockalsash@gmail.com> | 2014-01-08 22:25:55 +0400 |
|---|---|---|
| committer | Sv. Lockal <lockalsash@gmail.com> | 2014-01-08 22:25:55 +0400 |
| commit | 20b046d7639c6c95d942760f8004c449fc42b081 (patch) | |
| tree | ecd6332fbb37a260c8ef93aa88a0a3750962f9b8 /intern/cycles/kernel/svm/svm_noise.h | |
| parent | 61c9cacbd73f08536196d406a73aca83cd2a87f1 (diff) | |
Cycles: workaround for noise performance regression in CUDA 5.5
Use manual ternary operation widening in grad(). Without it nvcc 5.5 produces multiple branch splits with very big branches (because of inlining). This solves 19% performance regression for BMW1M-MikePan.blend.
Also remove one redundant instruction in perlin SSE (when h == 12 or h == 14, then h is always >= 4).
Reviewed By: brecht
Differential Revision: https://developer.blender.org/D190
Diffstat (limited to 'intern/cycles/kernel/svm/svm_noise.h')
| -rw-r--r-- | intern/cycles/kernel/svm/svm_noise.h | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/intern/cycles/kernel/svm/svm_noise.h b/intern/cycles/kernel/svm/svm_noise.h index add5f4c1ce1..a58dfdf4f9a 100644 --- a/intern/cycles/kernel/svm/svm_noise.h +++ b/intern/cycles/kernel/svm/svm_noise.h @@ -167,7 +167,8 @@ ccl_device float grad(int hash, float x, float y, float z) // use vectors pointing to the edges of the cube int h = hash & 15; float u = h<8 ? x : y; - float v = h<4 ? y : h == 12 || h == 14 ? x : z; + float vt = ((h == 12) | (h == 14)) ? x : z; + float v = h < 4 ? y : vt; return ((h&1) ? -u : u) + ((h&2) ? -v : v); } @@ -185,11 +186,10 @@ ccl_device_inline __m128 grad_sse(const __m128i *hash, const __m128 *x, const __ __m128i case_vy = _mm_cmplt_epi32(h, _mm_set1_epi32(4)); // 0xffffffff if h < 4 else 0 - __m128i case_h12_raw = _mm_cmpeq_epi32(h, _mm_set1_epi32(12)); // 0xffffffff if h == 12 else 0 - __m128i case_h14_raw = _mm_cmpeq_epi32(h, _mm_set1_epi32(14)); // 0xffffffff if h == 14 else 0 + __m128i case_h12 = _mm_cmpeq_epi32(h, _mm_set1_epi32(12)); // 0xffffffff if h == 12 else 0 + __m128i case_h14 = _mm_cmpeq_epi32(h, _mm_set1_epi32(14)); // 0xffffffff if h == 14 else 0 - __m128i case_vxtmp = _mm_or_si128(case_h12_raw, case_h14_raw); // 0xffffffff if h == 12 or h == 14 else 0 - __m128i case_vx = _mm_andnot_si128(case_vy, case_vxtmp); // 0xffffffff if (h == 12 or h == 14) and not(h<4) + __m128i case_vx = _mm_or_si128(case_h12, case_h14); // 0xffffffff if h == 12 or h == 14 else 0 __m128 v = blend(_mm_castsi128_ps(case_vy), *y, blend(_mm_castsi128_ps(case_vx), *x, *z)); // v = h<4 ? y : h == 12 || h == 14 ? x : z |