pan/mdg: Remove writeout case from bytemask_of_read_components

By setting the swizzle for the fragment color, and setting qmask to ~0
for branches, the special case for writeout branches can be removed
from mir_bytemask_of_read_components_index.

Reviewed-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/5065>

diff --git a/src/panfrost/midgard/midgard_compile.c b/src/panfrost/midgard/midgard_compile.c
index 2d0cb13aa21565d611af022b2a2f433013055d35..010ecd203fbe86d967f2dffd19d073f0198d520a 100644 (file)
--- a/src/panfrost/midgard/midgard_compile.c
+++ b/src/panfrost/midgard/midgard_compile.c
@@ -1314,6 +1314,8 @@ emit_fragment_store(compiler_context *ctx, unsigned src, enum midgard_rt_id rt)
         ins.src_types[0] = nir_type_uint32;
         ins.constants.u32[0] = rt == MIDGARD_ZS_RT ?
                                0xFF : (rt - MIDGARD_COLOR_RT0) * 0x100;
+        for (int i = 0; i < 4; ++i)
+                ins.swizzle[0][i] = i;
 
         /* Emit the branch */
         br = emit_mir_instruction(ctx, ins);
@@ -2236,6 +2238,7 @@ emit_fragment_epilogue(compiler_context *ctx, unsigned rt)
         ins.writeout_stencil = br->writeout_stencil;
         ins.branch.target_block = ctx->block_count - 1;
         ins.constants.u32[0] = br->constants.u32[0];
+        memcpy(&ins.src_types, &br->src_types, sizeof(ins.src_types));
         emit_mir_instruction(ctx, ins);
 
         ctx->current_block->epilogue = true;

diff --git a/src/panfrost/midgard/mir.c b/src/panfrost/midgard/mir.c
index 771d600e945feff76d75b60c3d323a5ba73ba72a..75a4e38fcac77fbb946bafb2e8643d209279017f 100644 (file)
--- a/src/panfrost/midgard/mir.c
+++ b/src/panfrost/midgard/mir.c
@@ -268,20 +268,6 @@ mir_bytemask_of_read_components_single(unsigned *swizzle, unsigned inmask, unsig
 uint16_t
 mir_bytemask_of_read_components_index(midgard_instruction *ins, unsigned i)
 {
-        if (ins->compact_branch && ins->writeout && (i == 0)) {
-                /* Non-ZS writeout uses all components */
-                if (!ins->writeout_depth && !ins->writeout_stencil)
-                        return 0xFFFF;
-
-                /* For ZS-writeout, if both Z and S are written we need two
-                 * components, otherwise we only need one.
-                 */
-                if (ins->writeout_depth && ins->writeout_stencil)
-                        return 0xFF;
-                else
-                        return 0xF;
-        }
-
         /* Conditional branches read one 32-bit component = 4 bytes (TODO: multi branch??) */
         if (ins->compact_branch && ins->branch.conditional && (i == 0))
                 return 0xF;
@@ -289,7 +275,7 @@ mir_bytemask_of_read_components_index(midgard_instruction *ins, unsigned i)
         /* ALU ops act componentwise so we need to pay attention to
          * their mask. Texture/ldst does not so we don't clamp source
          * readmasks based on the writemask */
-        unsigned qmask = (ins->type == TAG_ALU_4) ? ins->mask : ~0;
+        unsigned qmask = ~0;
 
         /* Handle dot products and things */
         if (ins->type == TAG_ALU_4 && !ins->compact_branch) {
@@ -299,6 +285,8 @@ mir_bytemask_of_read_components_index(midgard_instruction *ins, unsigned i)
 
                 if (channel_override)
                         qmask = mask_of(channel_override);
+                else
+                        qmask = ins->mask;
         }
 
         return mir_bytemask_of_read_components_single(ins->swizzle[i], qmask,