Mesa (master): radv/winsys: Fix inequality for sparse buffer remapping.

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Module: Mesa
Branch: master
Commit: 2b12e6931ef240df44d2c0f9374d6575ad202675
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=2b12e6931ef240df44d2c0f9374d6575ad202675

Author: Bas Nieuwenhuizen <bas at basnieuwenhuizen.nl>
Date:   Sun Dec  6 16:05:41 2020 +0100

radv/winsys: Fix inequality for sparse buffer remapping.

Found a case where we mapped a range too many.

Per the comment the constraint is:

	/* [first, last] is exactly the range of ranges that either overlap the
	 * new parent, or are adjacent to it. This corresponds to the bind ranges
	 * that may change.
	 */

So that means that after the ++last we the ranges[last] should still
be adjacent. So we need to test the post-increment value to see whether
it is adjacent.

Failure case:
  ranges:
    0: 0 - ffff
    1: 10000 - 1ffff
    2: 20000 - 2ffff
    3: 30000 - 3ffff
  new range: 10000 - 1ffff

wrong first, last: 0,3
  However range 3 clearly isn't adjacent at all.

Fixes: 715df30a4e2 "radv/amdgpu: Add winsys implementation of virtual buffers."
Reviewed-by: Samuel Pitoiset <samuel.pitoiset at gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/7953>

---

 src/amd/vulkan/winsys/amdgpu/radv_amdgpu_bo.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/amd/vulkan/winsys/amdgpu/radv_amdgpu_bo.c b/src/amd/vulkan/winsys/amdgpu/radv_amdgpu_bo.c
index c04767cd3c7..5433bfa4a75 100644
--- a/src/amd/vulkan/winsys/amdgpu/radv_amdgpu_bo.c
+++ b/src/amd/vulkan/winsys/amdgpu/radv_amdgpu_bo.c
@@ -194,7 +194,7 @@ radv_amdgpu_winsys_bo_virtual_bind(struct radeon_winsys_bo *_parent,
 		++first;
 
 	last = first;
-	while(last + 1 < parent->range_count && parent->ranges[last].offset <= offset + size)
+	while(last + 1 < parent->range_count && parent->ranges[last + 1].offset <= offset + size)
 		++last;
 
 	/* Whether the first or last range are going to be totally removed or just