diff options
Diffstat (limited to 'src/gallium/drivers/cell')
-rw-r--r-- | src/gallium/drivers/cell/spu/spu_tri.c | 97 |
1 files changed, 42 insertions, 55 deletions
diff --git a/src/gallium/drivers/cell/spu/spu_tri.c b/src/gallium/drivers/cell/spu/spu_tri.c index 1ef75b386fa..322be1252e9 100644 --- a/src/gallium/drivers/cell/spu/spu_tri.c +++ b/src/gallium/drivers/cell/spu/spu_tri.c @@ -108,10 +108,15 @@ struct setup_stage { * turn. Currently fixed at 4 floats, but should change in time. * Codegen will help cope with this. */ - const struct vertex_header *vmax; - const struct vertex_header *vmid; - const struct vertex_header *vmin; - const struct vertex_header *vprovoke; + union { + struct { + const struct vertex_header *vmin; + const struct vertex_header *vmid; + const struct vertex_header *vmax; + const struct vertex_header *vprovoke; + }; + qword vertex_headers; + }; struct edge ebot; struct edge etop; @@ -457,55 +462,39 @@ setup_sort_vertices(const struct vertex_header *v0, /* determine bottom to top order of vertices */ { - float y0 = spu_extract(v0->data[0], 1); - float y1 = spu_extract(v1->data[0], 1); - float y2 = spu_extract(v2->data[0], 1); - if (y0 <= y1) { - if (y1 <= y2) { - /* y0<=y1<=y2 */ - setup.vmin = v0; - setup.vmid = v1; - setup.vmax = v2; - sign = -1.0f; - } - else if (y2 <= y0) { - /* y2<=y0<=y1 */ - setup.vmin = v2; - setup.vmid = v0; - setup.vmax = v1; - sign = -1.0f; - } - else { - /* y0<=y2<=y1 */ - setup.vmin = v0; - setup.vmid = v2; - setup.vmax = v1; - sign = 1.0f; - } - } - else { - if (y0 <= y2) { - /* y1<=y0<=y2 */ - setup.vmin = v1; - setup.vmid = v0; - setup.vmax = v2; - sign = 1.0f; - } - else if (y2 <= y1) { - /* y2<=y1<=y0 */ - setup.vmin = v2; - setup.vmid = v1; - setup.vmax = v0; - sign = 1.0f; - } - else { - /* y1<=y2<=y0 */ - setup.vmin = v1; - setup.vmid = v2; - setup.vmax = v0; - sign = -1.0f; - } - } + /* A table of shuffle patterns for putting vertex_header pointers into + correct order. Quite magical. */ + const vec_uchar16 sort_order_patterns[] = { + SHUFFLE4(A,B,C,C), + SHUFFLE4(C,A,B,C), + SHUFFLE4(A,C,B,C), + SHUFFLE4(B,C,A,C), + SHUFFLE4(B,A,C,C), + SHUFFLE4(C,B,A,C) }; + + /* The vertex_header pointers, packed for easy shuffling later */ + const vec_uint4 vs = {(unsigned)v0, (unsigned)v1, (unsigned)v2}; + + /* Collate y values into two vectors for comparison. + Using only one shuffle constant! ;) */ + const vec_float4 y_02_ = spu_shuffle(v0->data[0], v2->data[0], SHUFFLE4(0,B,b,C)); + const vec_float4 y_10_ = spu_shuffle(v1->data[0], v0->data[0], SHUFFLE4(0,B,b,C)); + const vec_float4 y_012 = spu_shuffle(y_02_, v1->data[0], SHUFFLE4(0,B,b,C)); + const vec_float4 y_120 = spu_shuffle(y_10_, v2->data[0], SHUFFLE4(0,B,b,C)); + + /* Perform comparison: {y0,y1,y2} > {y1,y2,y0} */ + const vec_uint4 compare = spu_cmpgt(y_012, y_120); + /* Compress the result of the comparison into 4 bits */ + const vec_uint4 gather = spu_gather(compare); + /* Subtract one to attain the index into the LUT. Magical. */ + const unsigned int index = spu_extract(gather, 0) - 1; + + /* Load the appropriate pattern and construct the desired vector. */ + setup.vertex_headers = (qword)spu_shuffle(vs, vs, sort_order_patterns[index]); + + /* Using the result of the comparison, set sign. + Very magical. */ + sign = ((si_to_uint(si_cntb((qword)gather)) == 2) ? 1.0f : -1.0f); } /* Check if triangle is completely outside the tile bounds */ @@ -545,8 +534,6 @@ setup_sort_vertices(const struct vertex_header *v0, setup.facing = (area * sign > 0.0f) ^ (spu.rasterizer.front_winding == PIPE_WINDING_CW); - setup.vprovoke = v2; - return TRUE; } |