radeonsi: reorganize si_draw_vbo for lower register pressure (part 1)

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>

diff --git a/src/gallium/drivers/radeonsi/si_state_draw.cpp b/src/gallium/drivers/radeonsi/si_state_draw.cpp
index 655e6fb..7433e58 100644 (file)
--- a/src/gallium/drivers/radeonsi/si_state_draw.cpp
+++ b/src/gallium/drivers/radeonsi/si_state_draw.cpp
@@ -1653,10 +1653,45 @@ static void si_draw_vbo(struct pipe_context *ctx,
                         const struct pipe_draw_start_count *draws,
                         unsigned num_draws)
 {
+   /* Keep code that uses the least number of local variables as close to the beginning
+    * of this function as possible to minimize register pressure.
+    *
+    * It doesn't matter where we return due to invalid parameters because such cases
+    * shouldn't occur in practice.
+    */
    struct si_context *sctx = (struct si_context *)ctx;
+
+   /* Recompute and re-emit the texture resource states if needed. */
+   unsigned dirty_tex_counter = p_atomic_read(&sctx->screen->dirty_tex_counter);
+   if (unlikely(dirty_tex_counter != sctx->last_dirty_tex_counter)) {
+      sctx->last_dirty_tex_counter = dirty_tex_counter;
+      sctx->framebuffer.dirty_cbufs |= ((1 << sctx->framebuffer.state.nr_cbufs) - 1);
+      sctx->framebuffer.dirty_zsbuf = true;
+      si_mark_atom_dirty(sctx, &sctx->atoms.s.framebuffer);
+      si_update_all_texture_descriptors(sctx);
+   }
+
+   unsigned dirty_buf_counter = p_atomic_read(&sctx->screen->dirty_buf_counter);
+   if (unlikely(dirty_buf_counter != sctx->last_dirty_buf_counter)) {
+      sctx->last_dirty_buf_counter = dirty_buf_counter;
+      /* Rebind all buffers unconditionally. */
+      si_rebind_buffer(sctx, NULL);
+   }
+
+   si_decompress_textures(sctx, u_bit_consecutive(0, SI_NUM_GRAPHICS_SHADERS));
+   si_need_gfx_cs_space(sctx, num_draws);
+
+   /* If we're using a secure context, determine if cs must be secure or not */
+   if (GFX_VERSION >= GFX9 && unlikely(radeon_uses_secure_bos(sctx->ws))) {
+      bool secure = si_gfx_resources_check_encrypted(sctx);
+      if (secure != sctx->ws->cs_is_secure(&sctx->gfx_cs)) {
+         si_flush_gfx_cs(sctx, RADEON_FLUSH_ASYNC_START_NEXT_GFX_IB_NOW |
+                               RADEON_FLUSH_TOGGLE_SECURE_SUBMISSION, NULL);
+      }
+   }
+
    struct si_state_rasterizer *rs = sctx->queued.named.rasterizer;
    struct pipe_resource *indexbuf = info->index.resource;
-   unsigned dirty_tex_counter, dirty_buf_counter;
    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;
@@ -1680,25 +1715,6 @@ static void si_draw_vbo(struct pipe_context *ctx,
       return;
    }
 
-   /* Recompute and re-emit the texture resource states if needed. */
-   dirty_tex_counter = p_atomic_read(&sctx->screen->dirty_tex_counter);
-   if (unlikely(dirty_tex_counter != sctx->last_dirty_tex_counter)) {
-      sctx->last_dirty_tex_counter = dirty_tex_counter;
-      sctx->framebuffer.dirty_cbufs |= ((1 << sctx->framebuffer.state.nr_cbufs) - 1);
-      sctx->framebuffer.dirty_zsbuf = true;
-      si_mark_atom_dirty(sctx, &sctx->atoms.s.framebuffer);
-      si_update_all_texture_descriptors(sctx);
-   }
-
-   dirty_buf_counter = p_atomic_read(&sctx->screen->dirty_buf_counter);
-   if (unlikely(dirty_buf_counter != sctx->last_dirty_buf_counter)) {
-      sctx->last_dirty_buf_counter = dirty_buf_counter;
-      /* Rebind all buffers unconditionally. */
-      si_rebind_buffer(sctx, NULL);
-   }
-
-   si_decompress_textures(sctx, u_bit_consecutive(0, SI_NUM_GRAPHICS_SHADERS));
-
    /* Set the rasterization primitive type.
     *
     * This must be done after si_decompress_textures, which can call
@@ -2029,20 +2045,12 @@ static void si_draw_vbo(struct pipe_context *ctx,
       }
    }
 
-   si_need_gfx_cs_space(sctx, num_draws);
-
-   /* If we're using a secure context, determine if cs must be secure or not */
-   if (GFX_VERSION >= GFX9 && unlikely(radeon_uses_secure_bos(sctx->ws))) {
-      bool secure = si_gfx_resources_check_encrypted(sctx);
-      if (secure != sctx->ws->cs_is_secure(&sctx->gfx_cs)) {
-         si_flush_gfx_cs(sctx, RADEON_FLUSH_ASYNC_START_NEXT_GFX_IB_NOW |
-                               RADEON_FLUSH_TOGGLE_SECURE_SUBMISSION, NULL);
-      }
-   }
-
    /* Since we've called si_context_add_resource_size for vertex buffers,
     * this must be called after si_need_cs_space, because we must let
     * need_cs_space flush before we add buffers to the buffer list.
+    *
+    * This must be done after si_update_shaders because si_update_shaders can
+    * flush the CS when enabling tess and GS rings.
     */
    if (sctx->bo_list_add_all_gfx_resources)
       si_gfx_resources_add_all_to_bo_list(sctx);