Add initial context implementation.

APIs: hipInit, hipCtxCreate.
Track TLS default ctx.  Set deviceID now changes the ctx.
Add first context test.

Change-Id: If1cb9989b5a04a36147e25e84904336c7b6f3d88

src/hip_context.cpp

@@ -0,0 +1,89 @@
+/*
+Copyright (c) 2015-2016 Advanced Micro Devices, Inc. All rights reserved.
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANNTY OF ANY KIND, EXPRESS OR
+IMPLIED, INNCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANNY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER INN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR INN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+//---
+// Driver initialization and reporting:
+
+#include <stack>
+
+#include "hip_runtime.h"
+#include "hcc_detail/hip_hcc.h"
+#include "hcc_detail/trace_helper.h"
+
+// Stack of contexts 
+thread_local std::stack<ihipCtx_t *>  tls_ctxStack;
+
+
+hipError_t hipInit(unsigned int flags)
+{
+    HIP_INIT_API(flags);
+    
+    hipError_t e = hipSuccess;
+
+    // Flags must be 0
+    if (flags != 0) {
+        e = hipErrorInvalidValue;
+    } 
+
+    return ihipLogStatus(e);
+}
+
+
+hipError_t hipCtxCreate(hipCtx_t *ctx, unsigned int flags,  hipDevice_t device)
+{
+    HIP_INIT_API(ctx, flags, device); // FIXME - review if we want to init 
+    hipError_t e = hipSuccess;
+
+    *ctx = new ihipCtx_t(device, g_deviceCnt, flags);
+    tls_defaultCtx = *ctx;
+    tls_ctxStack.push(*ctx);
+
+    return ihipLogStatus(e);
+}
+
+
+hipError_t hipDeviceGet(hipDevice_t *device, int deviceId)
+{
+    HIP_INIT_API(device, deviceId); // FIXME - review if we want to init 
+
+    *device = ihipGetDevice(deviceId);
+
+    hipError_t e = hipSuccess;
+    if (*device == NULL) {
+        e = hipErrorInvalidDevice;
+    }
+
+    return ihipLogStatus(e);
+};
+
+
+/**
+ * @return #hipSuccess
+ */
+//---
+hipError_t hipDriverGetVersion(int *driverVersion)
+{
+    HIP_INIT_API(driverVersion);
+
+    if (driverVersion) {
+        *driverVersion = 4;
+    }
+
+    return ihipLogStatus(hipSuccess);
+}