Mesa (master): i965: Perform basic optimizations on the BROADCAST opcode.

[Francisco Jerez]

Module: Mesa
Branch: master
Commit: f2fad0dc80627e853eea558498f18a9fa769992e
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=f2fad0dc80627e853eea558498f18a9fa769992e

Author: Francisco Jerez <currojerez at riseup.net>
Date:   Thu Feb 19 14:52:24 2015 +0200

i965: Perform basic optimizations on the BROADCAST opcode.

v2: Style fixes.

Reviewed-by: Matt Turner <mattst88 at gmail.com>

---

 src/mesa/drivers/dri/i965/brw_fs.cpp                   |   16 ++++++++++++++++
 src/mesa/drivers/dri/i965/brw_fs_copy_propagation.cpp  |    1 +
 src/mesa/drivers/dri/i965/brw_fs_cse.cpp               |    1 +
 src/mesa/drivers/dri/i965/brw_ir_fs.h                  |    7 +++++++
 src/mesa/drivers/dri/i965/brw_ir_vec4.h                |    7 +++++++
 src/mesa/drivers/dri/i965/brw_vec4.cpp                 |   10 ++++++++++
 .../drivers/dri/i965/brw_vec4_copy_propagation.cpp     |    1 +
 src/mesa/drivers/dri/i965/brw_vec4_cse.cpp             |    1 +
 8 files changed, 44 insertions(+)

diff --git a/src/mesa/drivers/dri/i965/brw_fs.cpp b/src/mesa/drivers/dri/i965/brw_fs.cpp
index f5e8dfa..182c79f 100644
--- a/src/mesa/drivers/dri/i965/brw_fs.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs.cpp
@@ -2546,6 +2546,22 @@ fs_visitor::opt_algebraic()
          }
          break;
       }
+      case SHADER_OPCODE_BROADCAST:
+         if (is_uniform(inst->src[0])) {
+            inst->opcode = BRW_OPCODE_MOV;
+            inst->sources = 1;
+            inst->force_writemask_all = true;
+            progress = true;
+         } else if (inst->src[1].file == IMM) {
+            inst->opcode = BRW_OPCODE_MOV;
+            inst->src[0] = component(inst->src[0],
+                                     inst->src[1].fixed_hw_reg.dw1.ud);
+            inst->sources = 1;
+            inst->force_writemask_all = true;
+            progress = true;
+         }
+         break;
+
       default:
 	 break;
       }
diff --git a/src/mesa/drivers/dri/i965/brw_fs_copy_propagation.cpp b/src/mesa/drivers/dri/i965/brw_fs_copy_propagation.cpp
index c9ce2bd..d926c1d 100644
--- a/src/mesa/drivers/dri/i965/brw_fs_copy_propagation.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs_copy_propagation.cpp
@@ -608,6 +608,7 @@ fs_visitor::try_constant_propagate(fs_inst *inst, acp_entry *entry)
          break;
 
       case FS_OPCODE_UNIFORM_PULL_CONSTANT_LOAD:
+      case SHADER_OPCODE_BROADCAST:
          inst->src[i] = val;
          progress = true;
          break;
diff --git a/src/mesa/drivers/dri/i965/brw_fs_cse.cpp b/src/mesa/drivers/dri/i965/brw_fs_cse.cpp
index c1d0616..8958e62 100644
--- a/src/mesa/drivers/dri/i965/brw_fs_cse.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs_cse.cpp
@@ -89,6 +89,7 @@ is_expression(const fs_inst *const inst)
    case FS_OPCODE_VARYING_PULL_CONSTANT_LOAD:
    case FS_OPCODE_CINTERP:
    case FS_OPCODE_LINTERP:
+   case SHADER_OPCODE_BROADCAST:
       return true;
    case SHADER_OPCODE_RCP:
    case SHADER_OPCODE_RSQ:
diff --git a/src/mesa/drivers/dri/i965/brw_ir_fs.h b/src/mesa/drivers/dri/i965/brw_ir_fs.h
index 1e54bb2..0727ac5 100644
--- a/src/mesa/drivers/dri/i965/brw_ir_fs.h
+++ b/src/mesa/drivers/dri/i965/brw_ir_fs.h
@@ -166,6 +166,13 @@ component(fs_reg reg, unsigned idx)
    return reg;
 }
 
+static inline bool
+is_uniform(const fs_reg &reg)
+{
+   return (reg.width == 1 || reg.stride == 0 || reg.is_null()) &&
+          (!reg.reladdr || is_uniform(*reg.reladdr));
+}
+
 /**
  * Get either of the 8-component halves of a 16-component register.
  *
diff --git a/src/mesa/drivers/dri/i965/brw_ir_vec4.h b/src/mesa/drivers/dri/i965/brw_ir_vec4.h
index 955a62d..a56fdd6 100644
--- a/src/mesa/drivers/dri/i965/brw_ir_vec4.h
+++ b/src/mesa/drivers/dri/i965/brw_ir_vec4.h
@@ -95,6 +95,13 @@ negate(src_reg reg)
    return reg;
 }
 
+static inline bool
+is_uniform(const src_reg &reg)
+{
+   return (reg.file == IMM || reg.file == UNIFORM || reg.is_null()) &&
+          (!reg.reladdr || is_uniform(*reg.reladdr));
+}
+
 class dst_reg : public backend_reg
 {
 public:
diff --git a/src/mesa/drivers/dri/i965/brw_vec4.cpp b/src/mesa/drivers/dri/i965/brw_vec4.cpp
index 4f75553..607129b 100644
--- a/src/mesa/drivers/dri/i965/brw_vec4.cpp
+++ b/src/mesa/drivers/dri/i965/brw_vec4.cpp
@@ -682,6 +682,16 @@ vec4_visitor::opt_algebraic()
          }
          break;
       }
+      case SHADER_OPCODE_BROADCAST:
+         if (is_uniform(inst->src[0]) ||
+             inst->src[1].is_zero()) {
+            inst->opcode = BRW_OPCODE_MOV;
+            inst->src[1] = src_reg();
+            inst->force_writemask_all = true;
+            progress = true;
+         }
+         break;
+
       default:
 	 break;
       }
diff --git a/src/mesa/drivers/dri/i965/brw_vec4_copy_propagation.cpp b/src/mesa/drivers/dri/i965/brw_vec4_copy_propagation.cpp
index 0fbf0ab..2d9afa8 100644
--- a/src/mesa/drivers/dri/i965/brw_vec4_copy_propagation.cpp
+++ b/src/mesa/drivers/dri/i965/brw_vec4_copy_propagation.cpp
@@ -152,6 +152,7 @@ try_constant_propagate(const struct brw_device_info *devinfo,
 
    switch (inst->opcode) {
    case BRW_OPCODE_MOV:
+   case SHADER_OPCODE_BROADCAST:
       inst->src[arg] = value;
       return true;
 
diff --git a/src/mesa/drivers/dri/i965/brw_vec4_cse.cpp b/src/mesa/drivers/dri/i965/brw_vec4_cse.cpp
index 100e511..66b531c 100644
--- a/src/mesa/drivers/dri/i965/brw_vec4_cse.cpp
+++ b/src/mesa/drivers/dri/i965/brw_vec4_cse.cpp
@@ -72,6 +72,7 @@ is_expression(const vec4_instruction *const inst)
    case BRW_OPCODE_MAD:
    case BRW_OPCODE_LRP:
    case VEC4_OPCODE_UNPACK_UNIFORM:
+   case SHADER_OPCODE_BROADCAST:
       return true;
    case SHADER_OPCODE_RCP:
    case SHADER_OPCODE_RSQ: