[Mesa-dev] [PATCH 53/53] intel/fs: Build 32-wide FS shaders.

[Jason Ekstrand]

From: Francisco Jerez <currojerez at riseup.net>

Co-authored-by: Jason Ekstrand <jason at jlekstrand.net>
---
 src/intel/compiler/brw_fs.cpp | 54 ++++++++++++++++++++++++++++++++++---------
 1 file changed, 43 insertions(+), 11 deletions(-)

diff --git a/src/intel/compiler/brw_fs.cpp b/src/intel/compiler/brw_fs.cpp
index c821a11..1c022de 100644
--- a/src/intel/compiler/brw_fs.cpp
+++ b/src/intel/compiler/brw_fs.cpp
@@ -7142,7 +7142,7 @@ brw_compile_fs(const struct brw_compiler *compiler, void *log_data,
    prog_data->barycentric_interp_modes =
       brw_compute_barycentric_interp_modes(compiler->devinfo, shader);
 
-   cfg_t *simd8_cfg = NULL, *simd16_cfg = NULL;
+   cfg_t *simd8_cfg = NULL, *simd16_cfg = NULL, *simd32_cfg = NULL;
 
    fs_visitor v8(compiler, log_data, mem_ctx, key,
                  &prog_data->base, prog, shader, 8,
@@ -7176,6 +7176,26 @@ brw_compile_fs(const struct brw_compiler *compiler, void *log_data,
       }
    }
 
+   /* Currently, the compiler only supports SIMD32 on SNB+ */
+   if (v8.max_dispatch_width >= 32 &&
+       compiler->devinfo->gen >= 6 &&
+       unlikely(INTEL_DEBUG & DEBUG_DO32)) {
+      /* Try a SIMD32 compile */
+      fs_visitor v32(compiler, log_data, mem_ctx, key,
+                     &prog_data->base, prog, shader, 32,
+                     shader_time_index32);
+      v32.import_uniforms(&v8);
+      if (!v32.run_fs(allow_spilling, false)) {
+         compiler->shader_perf_log(log_data,
+                                   "SIMD32 shader failed to compile: %s",
+                                   v32.fail_msg);
+      } else {
+         simd32_cfg = v32.cfg;
+         prog_data->dispatch_grf_start_reg_32 = v32.payload.num_regs;
+         prog_data->reg_blocks_32 = brw_register_blocks(v32.grf_used);
+      }
+   }
+
    /* When the caller requests a repclear shader, they want SIMD16-only */
    if (use_rep_send)
       simd8_cfg = NULL;
@@ -7185,8 +7205,17 @@ brw_compile_fs(const struct brw_compiler *compiler, void *log_data,
     * Instead, we just give them exactly one shader and we pick the widest one
     * available.
     */
-   if (compiler->devinfo->gen < 5 && simd16_cfg)
-      simd8_cfg = NULL;
+   if (compiler->devinfo->gen < 5) {
+      if (simd32_cfg || simd16_cfg)
+         simd8_cfg = NULL;
+      if (simd32_cfg)
+         simd16_cfg = NULL;
+   }
+
+   /* If computed depth is enabled SNB only allows SIMD8. */
+   if (compiler->devinfo->gen == 6 &&
+       prog_data->computed_depth_mode != BRW_PSCDEPTH_OFF)
+      assert(simd16_cfg == NULL && simd32_cfg == NULL);
 
    if (compiler->devinfo->gen <= 5 && !simd8_cfg) {
       /* Iron lake and earlier only have one Dispatch GRF start field.  Make
@@ -7195,6 +7224,9 @@ brw_compile_fs(const struct brw_compiler *compiler, void *log_data,
       if (simd16_cfg) {
          prog_data->base.dispatch_grf_start_reg =
             prog_data->dispatch_grf_start_reg_16;
+      } else if (simd32_cfg) {
+         prog_data->base.dispatch_grf_start_reg =
+            prog_data->dispatch_grf_start_reg_32;
       }
    }
 
@@ -7204,16 +7236,11 @@ brw_compile_fs(const struct brw_compiler *compiler, void *log_data,
        * through F (SNB PRM Vol. 2 Part 1 Section 7.7.1).  On all hardware
        * generations, the only configurations supporting persample dispatch
        * are are this in which only one dispatch width is enabled.
-       *
-       * If computed depth is enabled, SNB only allows SIMD8 while IVB+
-       * allow SIMD8 or SIMD16 so we choose SIMD16 if available.
        */
-      if (compiler->devinfo->gen == 6 &&
-          prog_data->computed_depth_mode != BRW_PSCDEPTH_OFF) {
-         simd16_cfg = NULL;
-      } else if (simd16_cfg) {
+      if (simd32_cfg || simd16_cfg)
          simd8_cfg = NULL;
-      }
+      if (simd32_cfg)
+         simd16_cfg = NULL;
    }
 
    /* We have to compute the flat inputs after the visitor is finished running
@@ -7243,6 +7270,11 @@ brw_compile_fs(const struct brw_compiler *compiler, void *log_data,
       prog_data->prog_offset_16 = g.generate_code(simd16_cfg, 16);
    }
 
+   if (simd32_cfg) {
+      prog_data->dispatch_32 = true;
+      prog_data->prog_offset_32 = g.generate_code(simd32_cfg, 32);
+   }
+
    return g.get_assembly();
 }
 
-- 
2.5.0.400.gff86faf