diff options
| author | Danylo Piliaiev <danylo.piliaiev@globallogic.com> | 2020-08-17 18:13:24 +0300 |
|---|---|---|
| committer | Eric Engestrom <eric@engestrom.ch> | 2020-09-02 21:50:43 +0200 |
| commit | 1d9aa0e99a5d8b5e9d4a762fceaa20ab67401358 (patch) | |
| tree | fb165d20a723d8ed85225c1bc251b93e6f59e5a0 | |
| parent | 6273688e65a80564228ea36f36bc5c5b44b3cb5b (diff) | |
ir_constant: Return zero on out-of-bounds vector accesses
Several optimization paths, including constant folding, can lead to
accessing an ir_constant vector with an out of bounds index.
Return 0 since GL_ARB_robustness and GL_KHR_robustness encourage
us to do so.
Fixes piglit tests:
spec@glsl-1.20@execution@vector-out-of-bounds-access@fs-vec4-out-of-bounds-2
spec@glsl-1.20@execution@vector-out-of-bounds-access@fs-vec4-out-of-bounds-4
spec@glsl-1.20@execution@vector-out-of-bounds-access@fs-vec4-out-of-bounds-5
Closes: https://gitlab.freedesktop.org/mesa/mesa/-/issues/2604
CC: <mesa-stable@lists.freedesktop.org>
Signed-off-by: Danylo Piliaiev <danylo.piliaiev@globallogic.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Marcin Ślusarz <marcin.slusarz@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6363>
(cherry picked from commit e93979ba599355c42df01a89073362b970489a3a)
| -rw-r--r-- | .pick_status.json | 2 | ||||
| -rw-r--r-- | src/compiler/glsl/ir.cpp | 14 |
2 files changed, 15 insertions, 1 deletions
diff --git a/.pick_status.json b/.pick_status.json index c108e806880..53a0109298d 100644 --- a/.pick_status.json +++ b/.pick_status.json @@ -3937,7 +3937,7 @@ "description": "ir_constant: Return zero on out-of-bounds vector accesses", "nominated": true, "nomination_type": 0, - "resolution": 0, + "resolution": 1, "master_sha": null, "because_sha": null }, diff --git a/src/compiler/glsl/ir.cpp b/src/compiler/glsl/ir.cpp index 922dcd3c819..12faf8e41fc 100644 --- a/src/compiler/glsl/ir.cpp +++ b/src/compiler/glsl/ir.cpp @@ -799,6 +799,20 @@ ir_constant::ir_constant(const ir_constant *c, unsigned i) this->const_elements = NULL; this->type = c->type->get_base_type(); + /* Section 5.11 (Out-of-Bounds Accesses) of the GLSL 4.60 spec says: + * + * In the subsections described above for array, vector, matrix and + * structure accesses, any out-of-bounds access produced undefined + * behavior....Out-of-bounds reads return undefined values, which + * include values from other variables of the active program or zero. + * + * GL_KHR_robustness and GL_ARB_robustness encourage us to return zero. + */ + if (i >= c->type->vector_elements) { + this->value = { { 0 } }; + return; + } + switch (this->type->base_type) { case GLSL_TYPE_UINT: this->value.u[0] = c->value.u[i]; break; case GLSL_TYPE_INT: this->value.i[0] = c->value.i[i]; break; |