* New support for Open Compute Project (OCP) floating-point `FP4`/`FP6`/`FP8` as the following. For details, see [Low precision floating point document](https://rocm.docs.amd.com/projects/HIP/en/latest/reference/low_fp_types.html).
- Data types for `FP4`/`FP6`/`FP8`.
- HIP APIs for `FP4`/`FP6`/`FP8`, which are compatible with corresponding CUDA APIs.
- HIP Extensions APIs for microscaling formats, which are supported on AMD GPUs.
* New `wptr` and `rptr` values in `ClPrint`, for better logging in dispatch barrier methods.
* New debug mask, to print precise code object information for logging.
* The `_sync()` version of crosslane builtins such as `shfl_sync()` and `__reduce_add_sync` are enabled by default. These can be disabled by setting the preprocessor macro `HIP_DISABLE_WARP_SYNC_BUILTINS`.
HIP runtime has the following functional improvements which greatly improve runtime performance and user experience.
* Reduced usage of the lock scope in events and kernel handling.
- Switches to `shared_mutex` for event validation, uses `std::unique_lock` in HIP runtime to create/destroy event, instead of `scopedLock`.
- Reduces the `scopedLock` in handling of kernel execution. HIP runtime now calls `scopedLock` during kernel binary creation/initialization,
doesn't call it again during kernel vector iteration before launch.
* Implementation of unifying managed buffer and kernel argument buffer so HIP runtime doesn't need to create/load a separate kernel argument buffer.
* Refactored memory validation, creates a unique function to validate a variety of memory copy operations.
* Improved kernel logging using demangling shader names.
* Advanced support for SPIRV, now kernel compilation caching is enabled by default. This feature is controlled by the environment variable `AMD_COMGR_CACHE`, for details, see [hip_rtc document](https://rocm.docs.amd.com/projects/HIP/en/latest/how-to/hip_rtc.html).
* Programmatic support for scratch limit on GPU device. Developer can now use the environment variable `HSA_SCRATCH_SINGLE_LIMIT` to change the default allocation size with expected scratch limit.
* HIP runtime now enables peer-to-peer (P2P) memory copies to utilize all available SDMA engines, rather than being limited to a single engine. It also selects the best engine first to give optimal bindwidth.
* Improved launch latency for `D2D` copies and `memset` on MI300 series.
* Support for the pointer attribute `HIP_POINTER_ATTRIBUTE_CONTEXT`.
### Optimized
* Improved implementation in `hipEventSynchronize`, HIP runtime now makes internal callbacks non-blocking to gain performance.
### Resolved issues
* Issue of dependency on `libgcc-s1` during rocm-dev install on Debian Buster. HIP runtime removed this Debian package dependency, and uses `libgcc1` instead for this distros.
* Building issue for `COMGR` dynamic load on Fedora and other Distros. HIP runtime now doesn't link against `libamd_comgr.so`.
* Failure in the API `hipStreamDestroy`, when stream type is `hipStreamLegacy`. The API now returns error code `hipErrorInvalidResourceHandle` on this condition.
* Kernel launch errors, such as `shared object initialization failed`, `invalid device function` or `kernel execution failure`. HIP runtime now loads `COMGR` properly considering the file with its name and mapped mage.
* Memory access fault in some appplications. HIP runtime fixed offset accumulation in memory address.
* The implementation of preventing `hipLaunchKernel` latency degradation with number of idle streams is reverted/disabled by default.
### Optimized
* Improved kernel logging includes de-mangling shader names.
* Refined implementation in HIP APIs `hipEventRecords` and `hipStreamWaitEvent` for performance improvement.
### Resolved issues
* Stale state during the graph capture. The return error was fixed, HIP runtime now always uses the latest dependent nodes during `hipEventRecord` capture.
* Segmentation fault during kernel execution. HIP runtime now allows maximum stack size as per ISA on the GPU device.
-`hipLinkAddData` adds SPIRV code object data to linker instance with options.
-`hipLinkAddFile` adds SPIRV code object file to linker instance with options.
-`hipLinkCreate` creates linker instance at runtime with options.
-`hipLinkComplete` completes linking of program and output linker binary to use with hipModuleLoadData.
-`hipLinkDestroy` deletes linker instance.
### Changed
* roc-obj* tools are being deprecated, and will be removed in an upcoming release.
- Perl package dependencies are now RECOMMENDS or SUGGESTS. Users will need to install these themselves.
- Support for ROCm Object tooling has moved into llvm-objdump provided by package rocm-llvm.
* SDMA retainer logic is removed for engine selection in operation of runtime buffer copy.
### Optimized
*`hipGraphLaunch` parallelism is improved for complex data-parallel graphs.
* Round-robin queue mechanism is updated for command scheduling. For multi-streams execution, HSA queue from null stream lock is freed and won't occupy the queue ID after the kernel in the stream is finished.
* The HIP runtime doesn't free bitcode object before code generation. It adds a cache, which allows compiled code objects to be reused instead of recompiling. This improves performance on multi-GPU systems.
* Runtime uses unified copy approach
- Unpinned `H2D`copies are no longer blocking until the size of 1MB.
- Kernel copy path is enabled for unpinned `H2D`/`D2H` methods.
- The default environment variable `GPU_FORCE_BLIT_COPY_SIZE` is set to `16`, which limits the kernel copy to sizes less than 16 KB, while copies about that would be handled by `SDMA` engine.
- Blit code is refactored and ASAN instrumentation is cleaned up.
* Out of memory error on Windows. When the user calls `hipMalloc` for device memory allocation while specifying a size larger than the available device memory, the HIP runtime fixes the error in the API implementation, allocating the available device memory plus system memory (shared virtual memory).
* Error of dependency on libgcc-s1 during rocm-dev install on Debian Buster. HIP runtime now uses libgcc1 for this distros.
* Stack corruption during kernel execution. HIP runtime now adds maximum stack size limit based on the GPU device feature.
### Upcoming changes
The following are the list of backwards incompatible changes planned for the upcoming major ROCm release.
* Signature changes in APIs to match corresponding CUDA APIs,
* Return error/value codes update in the following hip APIs, they now match the corresponding CUDA APIs,
-`hipModuleLaunchKernel`
-`hipExtModuleLaunchKernel`
-`hipModuleLaunchCooperativeKernel`
-`hipGetTextureAlignmentOffset`
-`hipTexObjectCreate`
-`hipBindTexture2D`
-`hipBindTextureToArray`
-`hipModuleLoad`
-`hipLaunchCooperativeKernelMultiDevice`
-`hipExtLaunchCooperativeKernelMultiDevice`
* HIPRTC implementation, the compilation of hiprtc now uses namespace ` __hip_internal`, instead of the standard headers `std`.
* Stream capture mode update in the following hip APIs. Stream can only be captured in relax mode, to match the behavior of the corresponding CUDA APIs,
* Tracking of Heterogeneous System Architecture (HSA) handlers:
- Adds an atomic counter to track the outstanding HSA handlers.
- Waits on CPU for the callbacks if the number exceeds the defined value.
* Codes to capture Architected Queueing Language (AQL) packets for HIP graph memory copy node between host and device. HIP enqueues AQL packets during graph launch.
* Control to use system pool implementation in runtime commands handling. By default, it is disabled.
* A new path to avoid `WaitAny` calls in `AsyncEventsLoop`. The new path is selected by default.
* Runtime control on decrement counter only if event is popped. There is a new way to restore dead signals cleanup for the old path.
* A new logic in runtime to track the age of events from the kernel mode driver.
### Optimized
* HSA callback performance. The HIP runtime creates and submits commands in the queue and interacts with HSA through a callback function. HIP waits for the CPU status from HSA to optimize handling of events, profiling, commands, and HSA signals for higher performance.
* Runtime optimisation which combines all logic of `WaitAny` in a single processing loop and avoids extra memory allocations or reference counting. The runtime won't spin on the CPU if all events are busy.
* Multi-threaded dispatches for performance improvement.
* Command submissions and processing between CPU and GPU by introducing a way to limit the software batch size.
* Switch to `std::shared_mutex` in book/keep logic in streams from multiple threads simultaneously, for performance improvement in specific customer applications.
*`std::shared_mutex` is used in memory object mapping, for performance improvement.
### Resolved issues
* Race condition in multi-threaded producer/consumer scenario with `hipMallocFromPoolAsync`.
* Segmentation fault with `hipStreamLegacy` while using the API `hipStreamWaitEvent`.
* Usage of `hipStreamLegacy` in HIP event record.
* A soft hang in graph execution process from HIP user object. The fix handles the release of graph execution object properly considering synchronization on the device/stream. The user application now behaves the same with hipUserObject on both the AMD ROCm and NVIDIA CUDA platforms.
- Added the optimized multistream path in graph execution. It uses a fixed number of async streams in the execution
- Optimized the launch latency, where commands creation and execution is done at the same time
- Optimized the scheduling to use less barriers and waiting signals if the same queue can be detected
- The new path is controlled by a new environment variable, with the options either to use the original path, or to force the number of asynchronous queues for execution.
- Added a new flag `integrated` support in device property
The `integrated` flag is added in the struct `hipDeviceProp_t`.
On the integrated `APU` system, the runtime driver detects and sets this flag to `1`, in which case the API `hipDeviceGetAttribute` returns enum `hipDeviceAttribute_t` for hipDeviceAttributeIntegrated as value `1`, for integrated GPU device.
The enum value `hipDeviceAttributeIntegrated` corresponds to `cudaDevAttrIntegrated` on CUDA platform.
The default value is 0 (disable), kernel will execute normally as defined in the queue. When this environment variable is set as 1 (enable), HIP runtime will serialize kernel enqueue, behaves the same as AMD_SERIALIZE_KERNEL.
- Added HIPRTC support for hip headers driver_types, math_functions, library_types, math_functions, hip_math_constants, channel_descriptor, device_functions, hip_complex, surface_types, texture_types.
- Added `amd_hip_bf16.h` which adds `bfloat16` type. These definitions are accessible via `#include <hip/hip_bf16.h>`
This header exists alongside the older bfloat16 header in`amd_hip_bfloat16.h` which is included via `hip/hip_bfloat16.h`. Users are recommended to use `<hip/hip_bf16.h>` instead of `<hip/hip_bfloat16.h>`.
- With ROCm 6.0, the HIP version is 6.0. As the HIP runtime binary suffix is updated in every major ROCm release, in ROCm 6.0, the new filename is libamdhip64.so.6. Furthermore, in ROCm 6.0 release, the libamdhip64.so.5 binary from ROCm 5.7 is made available to maintain binary backward compatibility with ROCm 5.x.
- Data types for members in HIP_MEMCPY3D structure are changed from "unsigned int" to "size_t".
- The value of the flag hipIpcMemLazyEnablePeerAccess is changed to “0x01”, which was previously defined as “0”.
- Some device property attributes are not currently support in HIP runtime, in order to maintain consistency, the following related enumeration names are changed in hipDeviceAttribute_t
- hipDeviceAttributeName is changed to hipDeviceAttributeUnused1
- hipDeviceAttributeUuid is changed to hipDeviceAttributeUnused2
- hipDeviceAttributeArch is changed to hipDeviceAttributeUnused3
- hipDeviceAttributeGcnArch is changed to hipDeviceAttributeUnused4
- hipDeviceAttributeGcnArchName is changed to hipDeviceAttributeUnused5
- Kernel launch maximum dimension validation is added specifically on gridY and gridZ in the HIP API hipModule-LaunchKernel. As a result,when hipGetDeviceAttribute is called for the value of hipDeviceAttributeMaxGrid-Dim, the behavior on the AMD platform is equivalent to NVIDIA.
- The HIP stream synchronisation behavior is changed in internal stream functions, in which a flag "wait" is added and set when the current stream is null pointer while executing stream synchronisation on other explicitly created streams. This change avoids blocking of execution on null/default stream.
The change won't affect usage of applications, and makes them behave the same on the AMD platform as NVIDIA.
- Error handling behavior on unsupported GPU is fixed, HIP runtime will log out error message, instead of creating signal abortion error which is invisible to developers but continued kernel execution process. This is for the case when developers compile any application via hipcc, setting the option --offload-arch with GPU ID which is different from the one on the system.
- Dynamically loaded HIP runtime library references incorrect version of hipDeviceGetProperties and hipChooseDevice APIs
When an application dynamically loads the HIP runtime library from ROCm 6.0 and attempts to get the hipDeviceGetProperties and/or hipChooseDevice entry-points using dlsym, the application gets the older version (ROCm 5.7) of those entry-points.
As a workaround, while compiling with ROCm 6.0, use the string "hipDeviceGetPropertiesR0600", and "hipChooseDeviceR0600" respectively for hipDeviceGetProperties and hipChooseDevice APIs.
- Added hipStreamGetDevice implementation to get the device assocaited with the stream
- Added HIP_AD_FORMAT_SIGNED_INT16 in hipArray formats
- hipArrayGetInfo for getting information about the specified array
- hipArrayGetDescriptor for getting 1D or 2D array descriptor
- hipArray3DGetDescriptor to get 3D array descriptor
### Changed
- hipMallocAsync to return success for zero size allocation to match hipMalloc
- Separation of hipcc perl binaries from HIP project to hipcc project. hip-devel package depends on newly added hipcc package
- Consolidation of hipamd, ROCclr, and OpenCL repositories into a single repository called clr. Instructions are updated to build HIP from sources in the HIP Installation guide
- Removed hipBusBandwidth and hipCommander samples from hip-tests
