[Mesa-dev] [PATCH] glsl: Expand matrix flip optimization pass to cover more cases.

[Iago Toral Quiroga]

Currently it only considers the cases of gl_ModelViewProjectionMatrix and
gl_TextureMatrix. The same optimization can be done also for
gl_ModelViewMatrix, gl_ProjectionMatrix and the corresponding inverses.
---
 src/glsl/opt_flip_matrices.cpp | 118 +++++++++++++++++++++++++++++++----------
 1 file changed, 91 insertions(+), 27 deletions(-)

diff --git a/src/glsl/opt_flip_matrices.cpp b/src/glsl/opt_flip_matrices.cpp
index 9044fd6..bf09b78 100644
--- a/src/glsl/opt_flip_matrices.cpp
+++ b/src/glsl/opt_flip_matrices.cpp
@@ -29,8 +29,9 @@
  * On some hardware, this is more efficient.
  *
  * This currently only does the conversion for built-in matrices which
- * already have transposed equivalents.  Namely, gl_ModelViewProjectionMatrix
- * and gl_TextureMatrix.
+ * already have transposed equivalents. Namely, gl_ModelViewMatrix,
+ * gl_ProjectionMatrix, gl_ModelViewProjectionMatrix, gl_TextureMatrix and
+ * their inverses.
  */
 #include "ir.h"
 #include "ir_optimization.h"
@@ -42,18 +43,39 @@ public:
    matrix_flipper(exec_list *instructions)
    {
       progress = false;
+      p_transpose = NULL;
+      p_inv_transpose = NULL;
+      mv_transpose = NULL;
+      mv_inv_transpose = NULL;
       mvp_transpose = NULL;
+      mvp_inv_transpose = NULL;
       texmat_transpose = NULL;
+      texmat_inv_transpose = NULL;
 
       foreach_list(n, instructions) {
          ir_instruction *ir = (ir_instruction *) n;
          ir_variable *var = ir->as_variable();
          if (!var)
             continue;
-         if (strcmp(var->name, "gl_ModelViewProjectionMatrixTranspose") == 0)
+
+         if (strcmp(var->name, "gl_ProjectionMatrixTranspose") == 0)
+            p_transpose = var;
+         else if (strcmp(var->name, "gl_ProjectionMatrixInverseTranspose") == 0)
+            p_inv_transpose = var;
+         else if (strcmp(var->name, "gl_ModelViewMatrixTranspose") == 0)
+            mv_transpose = var;
+         else if (strcmp(var->name, "gl_ModelViewMatrixInverseTranspose") == 0)
+            mv_inv_transpose = var;
+         else if (strcmp(var->name,
+                         "gl_ModelViewProjectionMatrixTranspose") == 0)
             mvp_transpose = var;
-         if (strcmp(var->name, "gl_TextureMatrixTranspose") == 0)
+         else if (strcmp(var->name,
+                         "gl_ModelViewProjectionMatrixInverseTranspose") == 0)
+            mvp_inv_transpose = var;
+         else if (strcmp(var->name, "gl_TextureMatrixTranspose") == 0)
             texmat_transpose = var;
+         else if (strcmp(var->name, "gl_TextureMatrixInverseTranspose") == 0)
+            texmat_inv_transpose = var;
       }
    }
 
@@ -62,11 +84,49 @@ public:
    bool progress;
 
 private:
+   ir_variable *p_transpose;
+   ir_variable *p_inv_transpose;
+   ir_variable *mv_transpose;
+   ir_variable *mv_inv_transpose;
    ir_variable *mvp_transpose;
+   ir_variable *mvp_inv_transpose;
    ir_variable *texmat_transpose;
+   ir_variable *texmat_inv_transpose;
 };
 }
 
+static void
+transform_operands(ir_expression *ir,
+                   ir_variable *mat_var, ir_variable *mat_transpose)
+{
+#ifndef NDEBUG
+   ir_dereference_variable *deref = ir->operands[0]->as_dereference_variable();
+   assert(deref && deref->var == mat_var);
+#endif
+
+   void *mem_ctx = ralloc_parent(ir);
+   ir->operands[0] = ir->operands[1];
+   ir->operands[1] = new(mem_ctx) ir_dereference_variable(mat_transpose);
+}
+
+static void
+transform_operands_texmat(ir_expression *ir,
+                          ir_variable *mat_var, ir_variable *mat_transpose)
+{
+   ir_dereference_array *array_ref = ir->operands[0]->as_dereference_array();
+   assert(array_ref != NULL);
+   ir_dereference_variable *var_ref = array_ref->array->as_dereference_variable();
+   assert(var_ref && var_ref->var == mat_var);
+
+   ir->operands[0] = ir->operands[1];
+   ir->operands[1] = array_ref;
+
+   var_ref->var = mat_transpose;
+
+   mat_transpose->data.max_array_access =
+      MAX2(mat_transpose->data.max_array_access, mat_var->data.max_array_access);
+}
+
 ir_visitor_status
 matrix_flipper::visit_enter(ir_expression *ir)
 {
@@ -81,32 +141,36 @@ matrix_flipper::visit_enter(ir_expression *ir)
 
    if (mvp_transpose &&
        strcmp(mat_var->name, "gl_ModelViewProjectionMatrix") == 0) {
-#ifndef NDEBUG
-      ir_dereference_variable *deref = ir->operands[0]->as_dereference_variable();
-      assert(deref && deref->var == mat_var);
-#endif
-
-      void *mem_ctx = ralloc_parent(ir);
-
-      ir->operands[0] = ir->operands[1];
-      ir->operands[1] = new(mem_ctx) ir_dereference_variable(mvp_transpose);
-
+      transform_operands(ir, mat_var, mvp_transpose);
+      progress = true;
+   } else if (mvp_inv_transpose &&
+              strcmp(mat_var->name,
+                     "gl_ModelViewProjectionMatrixInverse") == 0) {
+      transform_operands(ir, mat_var, mvp_inv_transpose);
+      progress = true;
+   } else if (p_transpose &&
+              strcmp(mat_var->name, "gl_ProjectionMatrix") == 0) {
+      transform_operands(ir, mat_var, p_transpose);
+      progress = true;
+   } else if (p_inv_transpose &&
+              strcmp(mat_var->name, "gl_ProjectionMatrixInverse") == 0) {
+      transform_operands(ir, mat_var, p_inv_transpose);
+      progress = true;
+   } else if (mv_transpose &&
+              strcmp(mat_var->name, "gl_ModelViewMatrix") == 0) {
+      transform_operands(ir, mat_var, mv_transpose);
+      progress = true;
+   } else if (mv_inv_transpose &&
+              strcmp(mat_var->name, "gl_ModelViewMatrixInverse") == 0) {
+      transform_operands(ir, mat_var, mv_inv_transpose);
       progress = true;
    } else if (texmat_transpose &&
               strcmp(mat_var->name, "gl_TextureMatrix") == 0) {
-      ir_dereference_array *array_ref = ir->operands[0]->as_dereference_array();
-      assert(array_ref != NULL);
-      ir_dereference_variable *var_ref = array_ref->array->as_dereference_variable();
-      assert(var_ref && var_ref->var == mat_var);
-
-      ir->operands[0] = ir->operands[1];
-      ir->operands[1] = array_ref;
-
-      var_ref->var = texmat_transpose;
-
-      texmat_transpose->data.max_array_access =
-         MAX2(texmat_transpose->data.max_array_access, mat_var->data.max_array_access);
-
+      transform_operands_texmat(ir, mat_var, texmat_transpose);
+      progress = true;
+   } else if (texmat_inv_transpose &&
+              strcmp(mat_var->name, "gl_TextureMatrixInverse") == 0) {
+      transform_operands_texmat(ir, mat_var, texmat_inv_transpose);
       progress = true;
    }
 
-- 
1.8.3.2