[Mesa-dev] [PATCH 3/6] i965/reg_allocate: Use make_reg_conflicts_transitive

[Jason Ekstrand]

Instead of adding transitive conflicts as we go, we now add regular
conflicts and them make them all transitive at the end.  This should be
more efficient.
---
 src/mesa/drivers/dri/i965/brw_fs_reg_allocate.cpp   | 10 ++++++++--
 src/mesa/drivers/dri/i965/brw_vec4_reg_allocate.cpp |  5 ++++-
 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 b70895e..1d39858 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 617c988..d7b6ad5 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++)
-- 
2.4.3