Mesa (master): compiler/spirv: implement 16-bit bitcasts

[Iago Toral Quiroga]

Module: Mesa
Branch: master
Commit: 1dacb562792782ca7793674ff5e7fc796b044915
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=1dacb562792782ca7793674ff5e7fc796b044915

Author: Iago Toral Quiroga <itoral at igalia.com>
Date:   Tue Apr 17 10:22:43 2018 +0200

compiler/spirv: implement 16-bit bitcasts

Reviewed-by: Jason Ekstrand <jason at jlekstrand.net>

---

 src/compiler/spirv/vtn_alu.c | 31 ++++++++++++++++++++++---------
 1 file changed, 22 insertions(+), 9 deletions(-)

diff --git a/src/compiler/spirv/vtn_alu.c b/src/compiler/spirv/vtn_alu.c
index b6f98483ec..5f9cc97fdf 100644
--- a/src/compiler/spirv/vtn_alu.c
+++ b/src/compiler/spirv/vtn_alu.c
@@ -251,10 +251,17 @@ vtn_handle_bitcast(struct vtn_builder *b, struct vtn_ssa_value *dest,
       vtn_assert(src_bit_size % dest_bit_size == 0);
       unsigned divisor = src_bit_size / dest_bit_size;
       for (unsigned comp = 0; comp < src_components; comp++) {
-         vtn_assert(src_bit_size == 64);
-         vtn_assert(dest_bit_size == 32);
-         nir_ssa_def *split =
-            nir_unpack_64_2x32(&b->nb, nir_channel(&b->nb, src, comp));
+         nir_ssa_def *split;
+         if (src_bit_size == 64) {
+            assert(dest_bit_size == 32 || dest_bit_size == 16);
+            split = dest_bit_size == 32 ?
+               nir_unpack_64_2x32(&b->nb, nir_channel(&b->nb, src, comp)) :
+               nir_unpack_64_4x16(&b->nb, nir_channel(&b->nb, src, comp));
+         } else {
+            vtn_assert(src_bit_size == 32);
+            vtn_assert(dest_bit_size == 16);
+            split = nir_unpack_32_2x16(&b->nb, nir_channel(&b->nb, src, comp));
+         }
          for (unsigned i = 0; i < divisor; i++)
             dest_chan[divisor * comp + i] = nir_channel(&b->nb, split, i);
       }
@@ -263,11 +270,17 @@ vtn_handle_bitcast(struct vtn_builder *b, struct vtn_ssa_value *dest,
       unsigned divisor = dest_bit_size / src_bit_size;
       for (unsigned comp = 0; comp < dest_components; comp++) {
          unsigned channels = ((1 << divisor) - 1) << (comp * divisor);
-         nir_ssa_def *src_chan =
-            nir_channels(&b->nb, src, channels);
-         vtn_assert(dest_bit_size == 64);
-         vtn_assert(src_bit_size == 32);
-         dest_chan[comp] = nir_pack_64_2x32(&b->nb, src_chan);
+         nir_ssa_def *src_chan = nir_channels(&b->nb, src, channels);
+         if (dest_bit_size == 64) {
+            assert(src_bit_size == 32 || src_bit_size == 16);
+            dest_chan[comp] = src_bit_size == 32 ?
+               nir_pack_64_2x32(&b->nb, src_chan) :
+               nir_pack_64_4x16(&b->nb, src_chan);
+         } else {
+            vtn_assert(dest_bit_size == 32);
+            vtn_assert(src_bit_size == 16);
+            dest_chan[comp] = nir_pack_32_2x16(&b->nb, src_chan);
+         }
       }
    }
    dest->def = nir_vec(&b->nb, dest_chan, dest_components);