On 11.08.2016 07:56, Tapani Pälli wrote:
Hi;
On 08/10/2016 09:34 PM, Nicolai Hähnle wrote:
From: Nicolai Hähnle <[email protected]>
Compared to the other array bounds tests, this one exercises a larger
array
size.
The motivation is for Radeon, where arrays can be lowered either into the
register file or into "real" memory. The larger array in this test
will be
sure to hit real memory.
---
tests/shaders/glsl-array-bounds-13.shader_test | 33
++++++++++++++++++++++++++
1 file changed, 33 insertions(+)
create mode 100644 tests/shaders/glsl-array-bounds-13.shader_test
diff --git a/tests/shaders/glsl-array-bounds-13.shader_test
b/tests/shaders/glsl-array-bounds-13.shader_test
new file mode 100644
index 0000000..95aa550
--- /dev/null
+++ b/tests/shaders/glsl-array-bounds-13.shader_test
@@ -0,0 +1,33 @@
+[require]
+GLSL >= 1.20
+
+[vertex shader passthrough]
+
+[fragment shader]
+/* Verify that out-of-bounds access to an array does not result in
any sort of
+ * program interruption.
+ *
+ * This test case uses a larger array, to cover drivers that have
different
+ * lowering paths for different array sizes.
+ *
+ * In this test case the array index will not be constant folded.
+ */
+#version 120
+
+uniform int idx;
+float array[32];
+
+void main()
+{
+ /* Ensure that there can be no constant folding due to undefined
values. */
+ array[0] = 0.0;
+ array[1] = 1.0;
+ gl_FragColor = vec4(0.0, 1.0, 0.0, array[idx]);
+}
+
+[test]
+uniform int idx -2
According to GLSL 1.20 specs (and up to 4.50 spec):
'Undefined behavior results from indexing an array with a non-constant
expression that’s greater than or equal to the array’s size or less than
0."
Having said that, we seem to have many similar tests so I guess it's
fine to assume some output from the shader, just wanted to prompt that
perhaps we are testing something that is undefined here?
I think you're right in theory. Undefined behavior might mean that the
pixel shader gets terminated without writing anything to the
framebuffer, though it definitely isn't allowed to mean program
termination or hangs.
In practice, given that nobody has complained about these tests in the
past, the UB seems to be limited to undefined data results in all
implementations... if anybody ever complains, we might have to remove
the probe checks from the test script.
Reviewed-by: Tapani Pälli <[email protected]>
Thanks!
Nicolai
+clear color 0.0 0.0 0.0 0.0
+clear
+draw rect -1 -1 2 2
+probe all rgb 0.0 1.0 0.0
// Tapani
_______________________________________________
Piglit mailing list
[email protected]
https://lists.freedesktop.org/mailman/listinfo/piglit
