i965: Define helper function to copy an arbitrary live component from some register.

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

4 files changed, 28 insertions, 0 deletions

diff --git a/src/mesa/drivers/dri/i965/brw_fs.h b/src/mesa/drivers/dri/i965/brw_fs.h
index 5f4ff15..d0c0037 100644
--- a/src/mesa/drivers/dri/i965/brw_fs.h
+++ b/src/mesa/drivers/dri/i965/brw_fs.h
@@ -325,6 +325,8 @@ public:
    void emit_minmax(enum brw_conditional_mod conditionalmod, const fs_reg &dst,
                     const fs_reg &src0, const fs_reg &src1);
    void emit_discard_jump();
+   /** Copy any live channel from \p src to the first channel of \p dst. */
+   void emit_uniformize(const fs_reg &dst, const fs_reg &src);
    bool try_emit_b2f_of_comparison(ir_expression *ir);
    bool try_emit_saturate(ir_expression *ir);
    bool try_emit_line(ir_expression *ir);
diff --git a/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp b/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp
index 5e453a1..fc05e77 100644
--- a/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp
@@ -335,6 +335,18 @@ fs_visitor::emit_minmax(enum brw_conditional_mod conditionalmod, const fs_reg &d
    }
 }
 
+void
+fs_visitor::emit_uniformize(const fs_reg &dst, const fs_reg &src)
+{
+   const fs_reg chan_index = vgrf(glsl_type::uint_type);
+
+   emit(SHADER_OPCODE_FIND_LIVE_CHANNEL, component(chan_index, 0))
+      ->force_writemask_all = true;
+   emit(SHADER_OPCODE_BROADCAST, component(dst, 0),
+        src, component(chan_index, 0))
+      ->force_writemask_all = true;
+}
+
 bool
 fs_visitor::try_emit_saturate(ir_expression *ir)
 {
diff --git a/src/mesa/drivers/dri/i965/brw_vec4.h b/src/mesa/drivers/dri/i965/brw_vec4.h
index 3f56c5c..628c631 100644
--- a/src/mesa/drivers/dri/i965/brw_vec4.h
+++ b/src/mesa/drivers/dri/i965/brw_vec4.h
@@ -299,6 +299,9 @@ public:
    void emit_lrp(const dst_reg &dst,
                  const src_reg &x, const src_reg &y, const src_reg &a);
 
+   /** Copy any live channel from \p src to the first channel of \p dst. */
+   void emit_uniformize(const dst_reg &dst, const src_reg &src);
+
    void emit_block_move(dst_reg *dst, src_reg *src,
                         const struct glsl_type *type, brw_predicate predicate);
 
diff --git a/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp b/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp
index e6ff870..7e405ab 100644
--- a/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp
+++ b/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp
@@ -1374,6 +1374,17 @@ vec4_visitor::emit_pull_constant_load_reg(dst_reg dst,
 }
 
 void
+vec4_visitor::emit_uniformize(const dst_reg &dst, const src_reg &src)
+{
+   const src_reg chan_index(this, glsl_type::uint_type);
+
+   emit(SHADER_OPCODE_FIND_LIVE_CHANNEL, dst_reg(chan_index))
+      ->force_writemask_all = true;
+   emit(SHADER_OPCODE_BROADCAST, dst, src, chan_index)
+      ->force_writemask_all = true;
+}
+
+void
 vec4_visitor::visit(ir_expression *ir)
 {
    unsigned int operand;