[Mesa-dev] [PATCH] mesa/math: Allocate memory for GLmatrix elements and its inverse contiguously

[Vlad Golovkin]

When GLmatrix elements and its inverse are stored contiguously in memory it is possible to
allocate, free and copy these fields with 1 function call instead of 2.
---
 src/mesa/math/m_matrix.c | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/src/mesa/math/m_matrix.c b/src/mesa/math/m_matrix.c
index 57a49533de..4ab78a1fb3 100644
--- a/src/mesa/math/m_matrix.c
+++ b/src/mesa/math/m_matrix.c
@@ -1438,8 +1438,7 @@ _math_matrix_is_dirty( const GLmatrix *m )
 void
 _math_matrix_copy( GLmatrix *to, const GLmatrix *from )
 {
-   memcpy(to->m, from->m, 16 * sizeof(GLfloat));
-   memcpy(to->inv, from->inv, 16 * sizeof(GLfloat));
+   memcpy(to->m, from->m, 16 * 2 * sizeof(GLfloat));
    to->flags = from->flags;
    to->type = from->type;
 }
@@ -1470,12 +1469,17 @@ _math_matrix_loadf( GLmatrix *mat, const GLfloat *m )
 void
 _math_matrix_ctr( GLmatrix *m )
 {
-   m->m = _mesa_align_malloc( 16 * sizeof(GLfloat), 16 );
+   m->m = _mesa_align_malloc( 16 * 2 * sizeof(GLfloat), 16 );
    if (m->m)
+   {
+      m->inv = m->m + 16;
       memcpy( m->m, Identity, sizeof(Identity) );
-   m->inv = _mesa_align_malloc( 16 * sizeof(GLfloat), 16 );
-   if (m->inv)
       memcpy( m->inv, Identity, sizeof(Identity) );
+   }
+   else
+   {
+      m->inv = NULL;
+   }
    m->type = MATRIX_IDENTITY;
    m->flags = 0;
 }
@@ -1493,7 +1497,6 @@ _math_matrix_dtr( GLmatrix *m )
    _mesa_align_free( m->m );
    m->m = NULL;
 
-   _mesa_align_free( m->inv );
    m->inv = NULL;
 }
 
-- 
2.14.1