[Mesa-dev] [RFC 24/27] i965/fs: Add helpers for de/normalizing values

[Topi Pohjolainen]

Signed-off-by: Topi Pohjolainen <topi.pohjolainen at intel.com>
---
 src/mesa/drivers/dri/i965/brw_fs.h           |  6 +++++
 src/mesa/drivers/dri/i965/brw_fs_visitor.cpp | 39 ++++++++++++++++++++++++++++
 2 files changed, 45 insertions(+)

diff --git a/src/mesa/drivers/dri/i965/brw_fs.h b/src/mesa/drivers/dri/i965/brw_fs.h
index 968ae77..2b3ac34 100644
--- a/src/mesa/drivers/dri/i965/brw_fs.h
+++ b/src/mesa/drivers/dri/i965/brw_fs.h
@@ -514,6 +514,12 @@ public:
    void visit_atomic_counter_intrinsic(ir_call *ir);
 
    fs_reg fetch_resinfo(int sampler, const fs_reg& lod);
+   void normalize(const fs_reg& norm,
+                  const fs_reg& unorm,
+                  const fs_reg& range);
+   void denormalize(const fs_reg& unorm,
+                    const fs_reg& norm,
+                    const fs_reg& range);
 
    struct gl_fragment_program *fp;
 
diff --git a/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp b/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp
index 42836ac..10afe5d 100644
--- a/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp
@@ -1589,6 +1589,45 @@ fs_visitor::fetch_resinfo(int sampler, const fs_reg& lod)
 }
 
 void
+fs_visitor::denormalize(const fs_reg& unorm,
+                        const fs_reg& norm,
+                        const fs_reg& range)
+{
+   fs_reg range_f = fs_reg(this, glsl_type::float_type);
+   fs_reg unorm_f = fs_reg(this, glsl_type::float_type);
+
+   /* Make sure the math is performed using floats - range is likely to be
+    * unsigned. Move will do the needed conversion and optimizing passes will
+    * remove the copy if the range is already a float.
+    */ 
+   emit(MOV(range_f, range));
+
+   emit(MUL(unorm_f, norm, range_f));
+
+   /* Such as range the unnormalized is likely to be unsigned. */
+   emit(MOV(unorm, unorm_f));
+}
+
+void
+fs_visitor::normalize(const fs_reg& norm,
+                      const fs_reg& unorm,
+                      const fs_reg& range)
+{
+   fs_reg range_inv = fs_reg(this, glsl_type::float_type);
+   fs_reg unorm_f = fs_reg(this, glsl_type::float_type);
+
+   /* Make sure the math is performed using floats - range and unnormalized
+    * are likely to be unsigned. Move will do the needed conversion and
+    * optimizing passes will remove the copies if they are already floats.
+    */ 
+   emit(MOV(range_inv, range));
+   emit(MOV(unorm_f, unorm));
+
+   emit(SHADER_OPCODE_RCP, range_inv, range_inv);
+   emit(MUL(norm, unorm_f, range_inv));
+}
+
+void
 fs_visitor::visit(ir_texture *ir)
 {
    fs_inst *inst = NULL;
-- 
1.8.3.1