From 26bb9126466be72504e4710f6530e2d43112d5fb Mon Sep 17 00:00:00 2001
From: Tom Deakin <tom.deakin@bristol.ac.uk>
Date: Tue, 3 May 2016 11:23:36 +0100
Subject: [PATCH] Check OCL device has enough memory for buffers

---
 src/OCLStream.cpp | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/src/OCLStream.cpp b/src/OCLStream.cpp
index ed419b5..e962ea5 100644
--- a/src/OCLStream.cpp
+++ b/src/OCLStream.cpp
@@ -53,8 +53,6 @@ OCLStream<T>::OCLStream(const unsigned int ARRAY_SIZE, const int device_index)
   if (!cached)
     getDeviceList();
 
-  array_size = ARRAY_SIZE;
-
   // Setup default OpenCL GPU
   if (device_index >= devices.size())
     throw std::runtime_error("Invalid device index");
@@ -85,6 +83,16 @@ OCLStream<T>::OCLStream(const unsigned int ARRAY_SIZE, const int device_index)
   add_kernel = new cl::KernelFunctor<cl::Buffer, cl::Buffer, cl::Buffer>(program, "add");
   triad_kernel = new cl::KernelFunctor<cl::Buffer, cl::Buffer, cl::Buffer>(program, "triad");
 
+  array_size = ARRAY_SIZE;
+
+  // Check buffers fit on the device
+  cl_ulong totalmem = device.getInfo<CL_DEVICE_GLOBAL_MEM_SIZE>();
+  cl_ulong maxbuffer = device.getInfo<CL_DEVICE_MAX_MEM_ALLOC_SIZE>();
+  if (maxbuffer < sizeof(T)*ARRAY_SIZE)
+    throw std::runtime_error("Device cannot allocate a buffer big enough");
+  if (totalmem < 3*sizeof(T)*ARRAY_SIZE)
+    throw std::runtime_error("Device does not have enough memory for all 3 buffers");
+
   // Create buffers
   d_a = cl::Buffer(context, CL_MEM_READ_WRITE, sizeof(T) * ARRAY_SIZE);
   d_b = cl::Buffer(context, CL_MEM_READ_WRITE, sizeof(T) * ARRAY_SIZE);