Mesa (main): panfrost: Enable NIR lowering of half float packing

[GitLab Mirror]

Module: Mesa
Branch: main
Commit: 1a4dca989c678f7b4056255a05fa683ba81f1046
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=1a4dca989c678f7b4056255a05fa683ba81f1046

Author: Icecream95 <ixn at disroot.org>
Date:   Wed Apr 27 08:23:35 2022 +1200

panfrost: Enable NIR lowering of half float packing

The GLSL lowering of half float packing involves software conversion
to half-float; instead, use the lowering in NIR.

Both Midgard and Bifrost are already set to lower the instructions to
bit operations, but change mdg_should_scalarize so that the lowerable
split variants of the pack/unpack instructions are generated.

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/16175>

---

 src/gallium/drivers/panfrost/pan_screen.c | 1 +
 src/panfrost/midgard/midgard_compile.c    | 2 ++
 2 files changed, 3 insertions(+)

diff --git a/src/gallium/drivers/panfrost/pan_screen.c b/src/gallium/drivers/panfrost/pan_screen.c
index 21ae980f4b4..00477b519c8 100644
--- a/src/gallium/drivers/panfrost/pan_screen.c
+++ b/src/gallium/drivers/panfrost/pan_screen.c
@@ -122,6 +122,7 @@ panfrost_get_param(struct pipe_screen *screen, enum pipe_cap param)
         case PIPE_CAP_FRAGMENT_SHADER_DERIVATIVES:
         case PIPE_CAP_FRAMEBUFFER_NO_ATTACHMENT:
         case PIPE_CAP_QUADS_FOLLOW_PROVOKING_VERTEX_CONVENTION:
+        case PIPE_CAP_SHADER_PACK_HALF_FLOAT:
                 return 1;
 
         case PIPE_CAP_MAX_RENDER_TARGETS:
diff --git a/src/panfrost/midgard/midgard_compile.c b/src/panfrost/midgard/midgard_compile.c
index b2f0a053ea5..cfa003c7f69 100644
--- a/src/panfrost/midgard/midgard_compile.c
+++ b/src/panfrost/midgard/midgard_compile.c
@@ -294,6 +294,8 @@ mdg_should_scalarize(const nir_instr *instr, const void *_unused)
         case nir_op_fdot2:
         case nir_op_umul_high:
         case nir_op_imul_high:
+        case nir_op_pack_half_2x16:
+        case nir_op_unpack_half_2x16:
                 return true;
         default:
                 return false;