i965/reg_allocate: Use make_reg_conflicts_transitive

Instead of adding transitive conflicts as we go, we now add regular
conflicts and them make them all transitive at the end.  This reduces
screen creation time substantially on BDW.  The time spent in eglInitialize
is reduced from 27.78 ms/call to 9.92 ms/call in debug mode and from 13.15
ms/call to 4.54 ms/call in release mode (about 65% in either case).

Reviewed-by: Eric Anholt <[email protected]>

2 files changed, 12 insertions, 3 deletions

diff --git a/src/mesa/drivers/dri/i965/brw_fs_reg_allocate.cpp b/src/mesa/drivers/dri/i965/brw_fs_reg_allocate.cpp
index b70895ec2ff..1d39858de86 100644
--- a/src/mesa/drivers/dri/i965/brw_fs_reg_allocate.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs_reg_allocate.cpp
@@ -232,7 +232,7 @@ brw_alloc_reg_set(struct brw_compiler *compiler, int dispatch_width)
             for (int base_reg = j;
                  base_reg < j + (class_sizes[i] + 1) / 2;
                  base_reg++) {
-               ra_add_transitive_reg_conflict(regs, base_reg, reg);
+               ra_add_reg_conflict(regs, base_reg, reg);
             }
 
             reg++;
@@ -246,7 +246,7 @@ brw_alloc_reg_set(struct brw_compiler *compiler, int dispatch_width)
             for (int base_reg = j;
                  base_reg < j + class_sizes[i];
                  base_reg++) {
-               ra_add_transitive_reg_conflict(regs, base_reg, reg);
+               ra_add_reg_conflict(regs, base_reg, reg);
             }
 
             reg++;
@@ -255,6 +255,12 @@ brw_alloc_reg_set(struct brw_compiler *compiler, int dispatch_width)
    }
    assert(reg == ra_reg_count);
 
+   /* Applying transitivity to all of the base registers gives us the
+    * appropreate register conflict relationships everywhere.
+    */
+   for (int reg = 0; reg < base_reg_count; reg++)
+      ra_make_reg_conflicts_transitive(regs, reg);
+
    /* Add a special class for aligned pairs, which we'll put delta_xy
     * in on Gen <= 6 so that we can do PLN.
     */
diff --git a/src/mesa/drivers/dri/i965/brw_vec4_reg_allocate.cpp b/src/mesa/drivers/dri/i965/brw_vec4_reg_allocate.cpp
index 617c9889cad..d7b6ad5fa0c 100644
--- a/src/mesa/drivers/dri/i965/brw_vec4_reg_allocate.cpp
+++ b/src/mesa/drivers/dri/i965/brw_vec4_reg_allocate.cpp
@@ -140,7 +140,7 @@ brw_vec4_alloc_reg_set(struct brw_compiler *compiler)
 	 for (int base_reg = j;
 	      base_reg < j + class_sizes[i];
 	      base_reg++) {
-	    ra_add_transitive_reg_conflict(compiler->vec4_reg_set.regs, base_reg, reg);
+	    ra_add_reg_conflict(compiler->vec4_reg_set.regs, base_reg, reg);
 	 }
 
 	 reg++;
@@ -158,6 +158,9 @@ brw_vec4_alloc_reg_set(struct brw_compiler *compiler)
    }
    assert(reg == ra_reg_count);
 
+   for (int reg = 0; reg < base_reg_count; reg++)
+      ra_make_reg_conflicts_transitive(compiler->vec4_reg_set.regs, reg);
+
    ra_set_finalize(compiler->vec4_reg_set.regs, q_values);
 
    for (int i = 0; i < MAX_VGRF_SIZE; i++)