Mesa (master): gallium/tgsi_exec: Fix assertion failure about missing constbufs.

[GitLab Mirror]

Module: Mesa
Branch: master
Commit: 671263b5c7639faf2f52700ae539952e2bbd63bd
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=671263b5c7639faf2f52700ae539952e2bbd63bd

Author: Eric Anholt <eric at anholt.net>
Date:   Thu Dec 10 11:34:48 2020 -0800

gallium/tgsi_exec: Fix assertion failure about missing constbufs.

GL by default gives you UB when you access a missing constbuf, and we were
crashing on debug builds in that case.  More importantly, we were
assertion failing even under valid circumstances, when a !ExecMask channel
had a bad value for the indirect buffer index and we tried to load from it
anyway.

In removing the assertion, also sink the buf declaration to after we've
done the bounds check that determines that there's a constbuf actually
bound to this index.

Reviewed-by: Marek Olšák <marek.olsak at amd.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/8196>

---

 .gitlab-ci/deqp-softpipe-fails.txt     | 1 -
 src/gallium/auxiliary/tgsi/tgsi_exec.c | 7 +++----
 2 files changed, 3 insertions(+), 5 deletions(-)

diff --git a/.gitlab-ci/deqp-softpipe-fails.txt b/.gitlab-ci/deqp-softpipe-fails.txt
index d084b31577e..a5650f19459 100644
--- a/.gitlab-ci/deqp-softpipe-fails.txt
+++ b/.gitlab-ci/deqp-softpipe-fails.txt
@@ -492,7 +492,6 @@ dEQP-GLES31.functional.image_load_store.early_fragment_tests.early_fragment_test
 dEQP-GLES31.functional.image_load_store.early_fragment_tests.early_fragment_tests_stencil_fbo,Fail
 dEQP-GLES31.functional.image_load_store.early_fragment_tests.no_early_fragment_tests_depth,Fail
 dEQP-GLES31.functional.image_load_store.early_fragment_tests.no_early_fragment_tests_depth_fbo,Fail
-dEQP-GLES31.functional.shaders.opaque_type_indexing.ubo.dynamically_uniform_geometry,Crash
 dEQP-GLES31.functional.state_query.integer.max_framebuffer_samples_getfloat,Fail
 dEQP-GLES31.functional.state_query.integer.max_framebuffer_samples_getinteger,Fail
 dEQP-GLES31.functional.state_query.integer.max_framebuffer_samples_getinteger64,Fail
diff --git a/src/gallium/auxiliary/tgsi/tgsi_exec.c b/src/gallium/auxiliary/tgsi/tgsi_exec.c
index c1f6ad1dd2d..b5fa1d8f263 100644
--- a/src/gallium/auxiliary/tgsi/tgsi_exec.c
+++ b/src/gallium/auxiliary/tgsi/tgsi_exec.c
@@ -1453,14 +1453,12 @@ fetch_src_file_channel(const struct tgsi_exec_machine *mach,
    case TGSI_FILE_CONSTANT:
       for (i = 0; i < TGSI_QUAD_SIZE; i++) {
          assert(index2D->i[i] >= 0 && index2D->i[i] < PIPE_MAX_CONSTANT_BUFFERS);
-         assert(mach->Consts[index2D->i[i]]);
 
          if (index->i[i] < 0) {
             chan->u[i] = 0;
          } else {
             /* NOTE: copying the const value as a uint instead of float */
             const uint constbuf = index2D->i[i];
-            const uint *buf = (const uint *)mach->Consts[constbuf];
             const int pos = index->i[i] * 4 + swizzle;
             /* const buffer bounds check */
             if (pos < 0 || pos >= (int) mach->ConstsSize[constbuf]) {
@@ -1472,9 +1470,10 @@ fetch_src_file_channel(const struct tgsi_exec_machine *mach,
                                   " out of bounds\n", pos);
                }
                chan->u[i] = 0;
-            }
-            else
+            } else {
+               const uint *buf = (const uint *)mach->Consts[constbuf];
                chan->u[i] = buf[pos];
+            }
          }
       }
       break;