[Piglit] [PATCH] arb_shader_storage_buffer_object: don't do out-of-bounds writes

[Samuel Iglesias Gonsálvez]

>From GLGL 4.5 spec, 5.11 "Out-of-Bounds Accesses":

"In the subsections described above for array, vector, matrix and
 structure accesses, any out-of-bounds access produced undefined
 behavior. However, if robust buffer access is enabled via the
 OpenGL API, such accesses will be bound within the memory extent
 of the active program."

These tests perform writes to an unsized array, however some of
these writes can be out-of-bounds and the result is undefined. As
the tests are focused on in-bound access and they don't enable
robust buffer access, then this patch removes the out-of-bounds writes
because we cannot assume they will be ignored.

Signed-off-by: Samuel Iglesias Gonsálvez <siglesias at igalia.com>
Cc: ahuillet at nvidia.com
---
 .../arb_shader_storage_buffer_object/layout-std140-write-shader.c   | 6 ++++--
 .../arb_shader_storage_buffer_object/layout-std430-write-shader.c   | 6 ++++--
 2 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/tests/spec/arb_shader_storage_buffer_object/layout-std140-write-shader.c b/tests/spec/arb_shader_storage_buffer_object/layout-std140-write-shader.c
index c67248e7a..914fc000f 100644
--- a/tests/spec/arb_shader_storage_buffer_object/layout-std140-write-shader.c
+++ b/tests/spec/arb_shader_storage_buffer_object/layout-std140-write-shader.c
@@ -63,7 +63,8 @@ static const char vs_pass_thru_text[] =
 	"       f = 4.0;\n"
 	"       s.a2[0] = vec2(6.0, 7.0); \n"
 	"       int index = int(v.x); // index should be zero\n"
-	"       unsized_array[index + gl_VertexID] = unsized_array.length();\n"
+	"       if ((index + gl_VertexID) < 4)\n"
+	"              unsized_array[index + gl_VertexID] = unsized_array.length();\n"
         "}\n";
 
 static const char fs_source[] =
@@ -91,7 +92,8 @@ static const char fs_source[] =
 	"       s.a2[1] = vec2(8.0, 9.0);\n"
 	"       s.a4 = mat2(10.0, 11.0, 12.0, 13.0);\n"
 	"       int index = int(v.z + gl_FragCoord.x);\n"
-	"       unsized_array[index] = unsized_array.length() * 2.0;\n"
+	"       if (index >= 0 && index < 4)\n"
+	"              unsized_array[index] = unsized_array.length() * 2.0;\n"
 	"}\n";
 
 GLuint prog;
diff --git a/tests/spec/arb_shader_storage_buffer_object/layout-std430-write-shader.c b/tests/spec/arb_shader_storage_buffer_object/layout-std430-write-shader.c
index 70c87a164..3d5dcdc47 100644
--- a/tests/spec/arb_shader_storage_buffer_object/layout-std430-write-shader.c
+++ b/tests/spec/arb_shader_storage_buffer_object/layout-std430-write-shader.c
@@ -86,7 +86,8 @@ static const char vs_pass_thru_text[] =
 	"       v3a[0].xz = vec2(39.0, 41.0);\n"
 	"       v3a[1].y = 43.0;\n"
 	"       int index = int(v.x); // index should be zero\n"
-	"       unsized_array[index + gl_VertexID] = unsized_array.length();\n"
+	"       if ((index + gl_VertexID) < 4)\n"
+	"              unsized_array[index + gl_VertexID] = unsized_array.length();\n"
 	"}\n";
 
 static const char fs_source[] =
@@ -126,7 +127,8 @@ static const char fs_source[] =
 	"       v3a[0].y = 40.0;\n"
 	"       v3a[1].xz = vec2(42.0, 44.0);\n"
 	"       int index = int(v.z + gl_FragCoord.x);\n"
-	"       unsized_array[index] = unsized_array.length() * 2.0;\n"
+	"       if (index >= 0 && index < 4)\n"
+	"              unsized_array[index] = unsized_array.length() * 2.0;\n"
 	"}\n";
 
 GLuint prog;
-- 
2.14.1