Mesa (master): swr/rast: Faster frustum prim culling

[George Kyriazis]

Module: Mesa
Branch: master
Commit: 7e813f62149b9141d2f8970d35ab7ffbd0e0637c
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=7e813f62149b9141d2f8970d35ab7ffbd0e0637c

Author: George Kyriazis <george.kyriazis at intel.com>
Date:   Wed Feb  7 12:24:23 2018 -0600

swr/rast: Faster frustum prim culling

Fix clipper validMask setting. We don't need to run frustum rejected
primitives through the clipper.  Perform frustum culling with only
frustum clip codes. Guardband clip codes cannot be used because they
overlap frustum codes.

Reviewed-By: Bruce Cherniak <bruce.cherniak at intel.com>

---

 src/gallium/drivers/swr/rasterizer/core/clip.h | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/src/gallium/drivers/swr/rasterizer/core/clip.h b/src/gallium/drivers/swr/rasterizer/core/clip.h
index 8d2590a498..0f8399c742 100644
--- a/src/gallium/drivers/swr/rasterizer/core/clip.h
+++ b/src/gallium/drivers/swr/rasterizer/core/clip.h
@@ -60,6 +60,7 @@ enum SWR_CLIPCODES
 };
 
 #define GUARDBAND_CLIP_MASK (FRUSTUM_NEAR|FRUSTUM_FAR|GUARDBAND_LEFT|GUARDBAND_TOP|GUARDBAND_RIGHT|GUARDBAND_BOTTOM|NEGW)
+#define FRUSTUM_CLIP_MASK (FRUSTUM_NEAR|FRUSTUM_FAR|FRUSTUM_LEFT|FRUSTUM_RIGHT|FRUSTUM_TOP|FRUSTUM_BOTTOM)
 
 template<typename SIMD_T>
 void ComputeClipCodes(const API_STATE &state, const Vec4<SIMD_T> &vertex, Float<SIMD_T> &clipCodes, Integer<SIMD_T> const &viewportIndexes)
@@ -708,15 +709,18 @@ public:
             primMask &= ~ComputeUserClipCullMask(pa, prim);
         }
 
-        // cull prims outside view frustum
         Float<SIMD_T> clipIntersection = ComputeClipCodeIntersection();
+        // Mask out non-frustum codes
+        clipIntersection = SIMD_T::and_ps(clipIntersection, SIMD_T::castsi_ps(SIMD_T::set1_epi32(FRUSTUM_CLIP_MASK)));
+
+        // cull prims outside view frustum
         int validMask = primMask & SimdHelper<SIMD_T>::cmpeq_ps_mask(clipIntersection, SIMD_T::setzero_ps());
 
         // skip clipping for points
         uint32_t clipMask = 0;
         if (NumVertsPerPrim != 1)
         {
-            clipMask = primMask & ComputeClipMask();
+            clipMask = validMask & ComputeClipMask();
         }
 
         AR_EVENT(ClipInfoEvent(numInvoc, validMask, clipMask));
@@ -726,7 +730,7 @@ public:
             RDTSC_BEGIN(FEGuardbandClip, pa.pDC->drawId);
             // we have to clip tris, execute the clipper, which will also
             // call the binner
-            ClipSimd(prim, SIMD_T::vmask_ps(primMask), SIMD_T::vmask_ps(clipMask), pa, primId, viewportIdx, rtIdx);
+            ClipSimd(prim, SIMD_T::vmask_ps(validMask), SIMD_T::vmask_ps(clipMask), pa, primId, viewportIdx, rtIdx);
             RDTSC_END(FEGuardbandClip, 1);
         }
         else if (validMask)