From: Eric Anholt <eric@anholt.net>
Date: Thu, 2 Aug 2018 00:38:25 +0000 (-0700)
Subject: v3d: Add some debug code for forcing register spilling.
X-Git-Tag: upstream/19.0.0~3332
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=f9d54dc3cf45ba6f15f74627b8ec527975ce5297;p=platform%2Fupstream%2Fmesa.git

v3d: Add some debug code for forcing register spilling.

This is useful for periodically testing out register spilling to see how
it goes on simple shaders, rather than only failing on insanely
complicated ones.
---

diff --git a/src/broadcom/compiler/vir_register_allocate.c b/src/broadcom/compiler/vir_register_allocate.c
index 5a856ac..598c408 100644
--- a/src/broadcom/compiler/vir_register_allocate.c
+++ b/src/broadcom/compiler/vir_register_allocate.c
@@ -520,6 +520,20 @@ v3d_register_allocate(struct v3d_compile *c, bool *spilled)
                 }
         }
 
+        /* Debug code to force a bit of register spilling, for running across
+         * conformance tests to make sure that spilling works.
+         */
+        int force_register_spills = 0;
+        if (c->spill_size < 16 * sizeof(uint32_t) * force_register_spills) {
+                int node = v3d_choose_spill_node(c, g, temp_to_node);
+                if (node != -1) {
+                        v3d_spill_reg(c, map[node].temp);
+                        ralloc_free(g);
+                        *spilled = true;
+                        return NULL;
+                }
+        }
+
         bool ok = ra_allocate(g);
         if (!ok) {
                 /* Try to spill, if we can't reduce threading first. */