i965/fs: Implement generator code for unsized array's length calculation

Signed-off-by: Samuel Iglesias Gonsalvez <siglesias@igalia.com>

5 files changed, 55 insertions, 0 deletions

diff --git a/src/mesa/drivers/dri/i965/brw_defines.h b/src/mesa/drivers/dri/i965/brw_defines.h
index e70e29d6b9..dcde86440c 100644
--- a/src/mesa/drivers/dri/i965/brw_defines.h
+++ b/src/mesa/drivers/dri/i965/brw_defines.h
@@ -967,6 +967,7 @@ enum opcode {
    FS_OPCODE_UNIFORM_PULL_CONSTANT_LOAD_GEN7,
    FS_OPCODE_VARYING_PULL_CONSTANT_LOAD,
    FS_OPCODE_VARYING_PULL_CONSTANT_LOAD_GEN7,
+   FS_OPCODE_UNSIZED_ARRAY_LENGTH,
    FS_OPCODE_MOV_DISPATCH_TO_FLAGS,
    FS_OPCODE_DISCARD_JUMP,
    FS_OPCODE_SET_OMASK,
diff --git a/src/mesa/drivers/dri/i965/brw_fs.cpp b/src/mesa/drivers/dri/i965/brw_fs.cpp
index 1e4db988f9..f3611bb687 100644
--- a/src/mesa/drivers/dri/i965/brw_fs.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs.cpp
@@ -778,6 +778,7 @@ fs_visitor::implied_mrf_writes(fs_inst *inst)
       return 1;
    case FS_OPCODE_FB_WRITE:
       return 2;
+   case FS_OPCODE_UNSIZED_ARRAY_LENGTH:
    case FS_OPCODE_UNIFORM_PULL_CONSTANT_LOAD:
    case SHADER_OPCODE_GEN4_SCRATCH_READ:
       return 1;
diff --git a/src/mesa/drivers/dri/i965/brw_fs.h b/src/mesa/drivers/dri/i965/brw_fs.h
index 88a50ae091..ea204d326b 100644
--- a/src/mesa/drivers/dri/i965/brw_fs.h
+++ b/src/mesa/drivers/dri/i965/brw_fs.h
@@ -456,6 +456,9 @@ private:
 			 struct brw_reg *src);
    void generate_tex(fs_inst *inst, struct brw_reg dst, struct brw_reg src,
                      struct brw_reg sampler_index);
+   void generate_unsized_array_length(fs_inst *inst, struct brw_reg dst,
+                                      struct brw_reg src,
+                                      struct brw_reg surf_index);
    void generate_math_gen6(fs_inst *inst,
                            struct brw_reg dst,
                            struct brw_reg src0,
diff --git a/src/mesa/drivers/dri/i965/brw_fs_generator.cpp b/src/mesa/drivers/dri/i965/brw_fs_generator.cpp
index 0fba88eb8e..2b453d9758 100644
--- a/src/mesa/drivers/dri/i965/brw_fs_generator.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs_generator.cpp
@@ -538,6 +538,50 @@ fs_generator::generate_math_g45(fs_inst *inst,
 }
 
 void
+fs_generator::generate_unsized_array_length(fs_inst *inst,
+                                            struct brw_reg dst,
+                                            struct brw_reg src,
+                                            struct brw_reg surf_index)
+{
+   assert(devinfo->gen >= 7);
+   assert(surf_index.file == BRW_IMMEDIATE_VALUE);
+
+   uint32_t simd_mode;
+   int rlen = 4;
+
+   switch (inst->exec_size) {
+   case 8:
+      simd_mode = BRW_SAMPLER_SIMD_MODE_SIMD8;
+      break;
+   case 16:
+      simd_mode = BRW_SAMPLER_SIMD_MODE_SIMD16;
+      break;
+   default:
+      unreachable("Invalid width for texture instruction");
+   }
+
+   if (simd_mode == BRW_SAMPLER_SIMD_MODE_SIMD16) {
+      rlen = 8;
+      dst = vec16(dst);
+   }
+
+   brw_SAMPLE(p,
+              retype(dst, BRW_REGISTER_TYPE_UW),
+              inst->base_mrf,
+              src,
+              surf_index.dw1.ud,
+              0,
+              GEN5_SAMPLER_MESSAGE_SAMPLE_RESINFO,
+              rlen, /* response length */
+              inst->mlen,
+              inst->header_size > 0,
+              simd_mode,
+              BRW_SAMPLER_RETURN_FORMAT_SINT32);
+
+   brw_mark_surface_used(prog_data, surf_index.dw1.ud);
+}
+
+void
 fs_generator::generate_tex(fs_inst *inst, struct brw_reg dst, struct brw_reg src,
                            struct brw_reg sampler_index)
 {
@@ -1935,6 +1979,9 @@ fs_generator::generate_code(const cfg_t *cfg, int dispatch_width)
          src[0].subnr = 4 * type_sz(src[0].type);
          brw_MOV(p, dst, stride(src[0], 8, 4, 1));
          break;
+      case FS_OPCODE_UNSIZED_ARRAY_LENGTH:
+         generate_unsized_array_length(inst, dst, src[0], src[1]);
+         break;
       case SHADER_OPCODE_TEX:
       case FS_OPCODE_TXB:
       case SHADER_OPCODE_TXD:
diff --git a/src/mesa/drivers/dri/i965/brw_shader.cpp b/src/mesa/drivers/dri/i965/brw_shader.cpp
index e75caea4a8..8e3ad49f76 100644
--- a/src/mesa/drivers/dri/i965/brw_shader.cpp
+++ b/src/mesa/drivers/dri/i965/brw_shader.cpp
@@ -642,6 +642,9 @@ brw_instruction_name(enum opcode op)
    case FS_OPCODE_PIXEL_Y:
       return "pixel_y";
 
+   case FS_OPCODE_UNSIZED_ARRAY_LENGTH:
+      return "fs_unsized_array_length";
+
    case FS_OPCODE_UNIFORM_PULL_CONSTANT_LOAD:
       return "uniform_pull_const";
    case FS_OPCODE_UNIFORM_PULL_CONSTANT_LOAD_GEN7: