radeonsi: reorganize si_draw_vbo for lower register pressure (part 2)

Move statements that use the least number of local variables as close
to the beginning as possible. Also move local variables closer to their use.

Reviewed-by: Pierre-Eric Pelloux-Prayer <pierre-eric.pelloux-prayer@amd.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/8794>

1 files changed, 62 insertions, 55 deletions

diff --git a/src/gallium/drivers/radeonsi/si_state_draw.cpp b/src/gallium/drivers/radeonsi/si_state_draw.cpp
index 7433e586e7e..30bbbd4bc0c 100644
--- a/src/gallium/drivers/radeonsi/si_state_draw.cpp
+++ b/src/gallium/drivers/radeonsi/si_state_draw.cpp
@@ -1690,58 +1690,6 @@ static void si_draw_vbo(struct pipe_context *ctx,
       }
    }
 
-   struct si_state_rasterizer *rs = sctx->queued.named.rasterizer;
-   struct pipe_resource *indexbuf = info->index.resource;
-   enum pipe_prim_type rast_prim, prim = info->mode;
-   unsigned index_size = info->index_size;
-   unsigned index_offset = indirect && indirect->buffer ? draws[0].start * index_size : 0;
-   unsigned instance_count = info->instance_count;
-   bool primitive_restart =
-      info->primitive_restart &&
-      (!sctx->screen->options.prim_restart_tri_strips_only ||
-       (prim != PIPE_PRIM_TRIANGLE_STRIP && prim != PIPE_PRIM_TRIANGLE_STRIP_ADJACENCY));
-
-   /* GFX6-GFX7 treat instance_count==0 as instance_count==1. There is
-    * no workaround for indirect draws, but we can at least skip
-    * direct draws.
-    */
-   if (GFX_VERSION <= GFX7 && unlikely(!indirect && !instance_count))
-      return;
-
-   struct si_shader_selector *vs = sctx->vs_shader.cso;
-   if (unlikely(!vs || sctx->num_vertex_elements < vs->num_vs_inputs ||
-                !sctx->ps_shader.cso || (HAS_TESS != (prim == PIPE_PRIM_PATCHES)))) {
-      assert(0);
-      return;
-   }
-
-   /* Set the rasterization primitive type.
-    *
-    * This must be done after si_decompress_textures, which can call
-    * draw_vbo recursively, and before si_update_shaders, which uses
-    * current_rast_prim for this draw_vbo call. */
-   if (HAS_GS) {
-      /* Only possibilities: POINTS, LINE_STRIP, TRIANGLES */
-      rast_prim = sctx->gs_shader.cso->rast_prim;
-   } else if (HAS_TESS) {
-      /* Only possibilities: POINTS, LINE_STRIP, TRIANGLES */
-      rast_prim = sctx->tes_shader.cso->rast_prim;
-   } else if (util_rast_prim_is_triangles(prim)) {
-      rast_prim = PIPE_PRIM_TRIANGLES;
-   } else {
-      /* Only possibilities, POINTS, LINE*, RECTANGLES */
-      rast_prim = prim;
-   }
-
-   if (rast_prim != sctx->current_rast_prim) {
-      if (util_prim_is_points_or_lines(sctx->current_rast_prim) !=
-          util_prim_is_points_or_lines(rast_prim))
-         si_mark_atom_dirty(sctx, &sctx->atoms.s.guardband);
-
-      sctx->current_rast_prim = rast_prim;
-      sctx->do_update_shaders = true;
-   }
-
    if (HAS_TESS) {
       struct si_shader_selector *tcs = sctx->tcs_shader.cso;
 
@@ -1773,6 +1721,23 @@ static void si_draw_vbo(struct pipe_context *ctx,
       }
    }
 
+   enum pipe_prim_type prim = info->mode;
+   unsigned instance_count = info->instance_count;
+
+   /* GFX6-GFX7 treat instance_count==0 as instance_count==1. There is
+    * no workaround for indirect draws, but we can at least skip
+    * direct draws.
+    */
+   if (GFX_VERSION <= GFX7 && unlikely(!indirect && !instance_count))
+      return;
+
+   struct si_shader_selector *vs = sctx->vs_shader.cso;
+   if (unlikely(!vs || sctx->num_vertex_elements < vs->num_vs_inputs ||
+                !sctx->ps_shader.cso || (HAS_TESS != (prim == PIPE_PRIM_PATCHES)))) {
+      assert(0);
+      return;
+   }
+
    if (GFX_VERSION <= GFX9 && HAS_GS) {
       /* Determine whether the GS triangle strip adjacency fix should
        * be applied. Rotate every other triangle if triangle strips with
@@ -1788,6 +1753,10 @@ static void si_draw_vbo(struct pipe_context *ctx,
       }
    }
 
+   struct pipe_resource *indexbuf = info->index.resource;
+   unsigned index_size = info->index_size;
+   unsigned index_offset = indirect && indirect->buffer ? draws[0].start * index_size : 0;
+
    if (index_size) {
       /* Translate or upload, if needed. */
       /* 8-bit indices are supported on GFX8. */
@@ -1834,9 +1803,6 @@ static void si_draw_vbo(struct pipe_context *ctx,
       }
    }
 
-   bool dispatch_prim_discard_cs = false;
-   bool prim_discard_cs_instancing = false;
-   unsigned original_index_size = index_size;
    unsigned min_direct_count = 0;
    unsigned total_direct_count = 0;
 
@@ -1869,6 +1835,15 @@ static void si_draw_vbo(struct pipe_context *ctx,
       }
    }
 
+   struct si_state_rasterizer *rs = sctx->queued.named.rasterizer;
+   bool primitive_restart =
+      info->primitive_restart &&
+      (!sctx->screen->options.prim_restart_tri_strips_only ||
+       (prim != PIPE_PRIM_TRIANGLE_STRIP && prim != PIPE_PRIM_TRIANGLE_STRIP_ADJACENCY));
+   bool dispatch_prim_discard_cs = false;
+   bool prim_discard_cs_instancing = false;
+   unsigned original_index_size = index_size;
+
    /* Determine if we can use the primitive discard compute shader. */
    if (ALLOW_PRIM_DISCARD_CS && !HAS_TESS && !HAS_GS &&
        (total_direct_count > sctx->prim_discard_vertex_count_threshold
@@ -1951,6 +1926,35 @@ static void si_draw_vbo(struct pipe_context *ctx,
       sctx->do_update_shaders = true;
    }
 
+   /* Set the rasterization primitive type.
+    *
+    * This must be done after si_decompress_textures, which can call
+    * draw_vbo recursively, and before si_update_shaders, which uses
+    * current_rast_prim for this draw_vbo call. */
+   enum pipe_prim_type rast_prim;
+
+   if (HAS_GS) {
+      /* Only possibilities: POINTS, LINE_STRIP, TRIANGLES */
+      rast_prim = sctx->gs_shader.cso->rast_prim;
+   } else if (HAS_TESS) {
+      /* Only possibilities: POINTS, LINE_STRIP, TRIANGLES */
+      rast_prim = sctx->tes_shader.cso->rast_prim;
+   } else if (util_rast_prim_is_triangles(prim)) {
+      rast_prim = PIPE_PRIM_TRIANGLES;
+   } else {
+      /* Only possibilities, POINTS, LINE*, RECTANGLES */
+      rast_prim = prim;
+   }
+
+   if (rast_prim != sctx->current_rast_prim) {
+      if (util_prim_is_points_or_lines(sctx->current_rast_prim) !=
+          util_prim_is_points_or_lines(rast_prim))
+         si_mark_atom_dirty(sctx, &sctx->atoms.s.guardband);
+
+      sctx->current_rast_prim = rast_prim;
+      sctx->do_update_shaders = true;
+   }
+
    /* Update NGG culling settings. */
    uint8_t old_ngg_culling = sctx->ngg_culling;
    if (GFX_VERSION >= GFX10) {
@@ -2055,6 +2059,9 @@ static void si_draw_vbo(struct pipe_context *ctx,
    if (sctx->bo_list_add_all_gfx_resources)
       si_gfx_resources_add_all_to_bo_list(sctx);
 
+   /* Graphics shader descriptors must be uploaded after si_update_shaders because
+    * it binds tess and GS ring buffers.
+    */
    if (unlikely(!si_upload_graphics_shader_descriptors(sctx) ||
                 !si_upload_vertex_buffer_descriptors<GFX_VERSION>(sctx))) {
       DRAW_CLEANUP;