From e187916de5a7474b548bff659ca518a5322eebac Mon Sep 17 00:00:00 2001
From: artemiipatov <patov.988@gmail.com>
Date: Sat, 30 Sep 2023 19:41:22 +0700
Subject: [PATCH] fix: spgemm negative maxAllocSize

---
 src/GraphBLAS-sharp.Backend/Objects/ClContextExtensions.fs | 2 +-
 src/GraphBLAS-sharp.Backend/Operations/SpGeMM/Expand.fs    | 4 +++-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/GraphBLAS-sharp.Backend/Objects/ClContextExtensions.fs b/src/GraphBLAS-sharp.Backend/Objects/ClContextExtensions.fs
index 3a7dca2c..f525e3cd 100644
--- a/src/GraphBLAS-sharp.Backend/Objects/ClContextExtensions.fs
+++ b/src/GraphBLAS-sharp.Backend/Objects/ClContextExtensions.fs
@@ -47,6 +47,6 @@ module ClContextExtensions =
 
             Cl
                 .GetDeviceInfo(this.ClDevice.Device, OpenCL.Net.DeviceInfo.MaxMemAllocSize, error)
-                .CastTo<int>()
+                .CastTo<uint64>()
             |> uint64
             |> ((*) 1UL<Byte>)
diff --git a/src/GraphBLAS-sharp.Backend/Operations/SpGeMM/Expand.fs b/src/GraphBLAS-sharp.Backend/Operations/SpGeMM/Expand.fs
index a57b38c6..09f04bb7 100644
--- a/src/GraphBLAS-sharp.Backend/Operations/SpGeMM/Expand.fs
+++ b/src/GraphBLAS-sharp.Backend/Operations/SpGeMM/Expand.fs
@@ -447,7 +447,9 @@ module internal Expand =
             let generalLength, segmentLengths =
                 getSegmentPointers processor leftMatrix.Columns rightMatrixRowsNNZ
 
-            if generalLength < maxAllocSize then
+            if generalLength = 0 then
+                None
+            elif generalLength < maxAllocSize then
                 segmentLengths.Free processor
 
                 runOneStep processor allocationMode leftMatrix rightMatrixRowsNNZ rightMatrix