Add Apple Metal GPU backend (OpenCL → Metal migration)#18
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Completes the Phase 0 milestone begun in 7b13b0f (GPU-op wrappers on OpenCL_T + mod_MCOpenCL routed through them): - Vendor Apple metal-cpp (macOS 15 / iOS 18, Apache-2.0) in-tree under ExternalProjects/metal-cpp/ so the future Metal backend build is self-contained. - MetalMigrationPlan.md: full OpenCL->Metal design doc plus a progress log recording that EMMCOpenCL output is bit-identical (h5diff -v on /EMData reports 0 differences in accum_e/accum_z/accumSP and metadata) between the develop and Phase 0 binaries — the wrapper seam is behavior-preserving. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
mod_DI.f90 (committed in dc6e3d4) is routed through the OpenCL_T GPU-op wrappers: InnerProdGPU, the three GPU drivers build/buffer blocks, the cl_expt/cl_dict host writes, and all releases. Verified via EMDI h5diff (develop vs Phase 0, same fixed Euler-angle dictionary): TopDotProductList, TopMatchIndices, EulerAngles, CI, Phi/Phi1/Phi2, KAM, OSM all show 0 differences -- the InnerProd GPU output and orientation results are bit-identical. Residual differences (DictionaryEulerAngles, ISM, ISMap, IndexingSuccessRate) are upstream of the dot products and trace to known FZ-sampling non-determinism, not this refactor. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Completes the Phase 0 active scope. mod_EBSDFull's embedded Monte Carlo sim and the C-callable mod_SEMCLwrappers (EMsoftCgetMCOpenCL) now call the OpenCL_T GPU-op wrappers instead of raw clfortran. Both use the same MC kernel and 14 arguments as the already-verified mod_MCOpenCL full mode. mod_CLsupport: added an optional 'quiet' flag to all GPU-op wrappers (via a checkq_ helper) that suppresses the fatal error_check (and build_program's build-log print). Default behavior is unchanged, so the already-verified MC/DI/EBSDFull non-quiet call paths are byte-for-byte identical. mod_SEMCLwrappers calls the wrappers with quiet=.TRUE. to preserve its original 'ignore CL errors, defer to caller' semantics, since it is invoked from external host programs where a hard stop would be incorrect. mod_HROSM confirmed to have no GPU code. mod_DIPCA (uncompiled, absent from all CMakeLists) still has raw clfortran calls and is left as a documented TODO. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Adds a working Metal compute backend alongside OpenCL, validated on the Monte Carlo path. Selected at build time via -DEMsoftOO_ENABLE_Metal_SUPPORT=ON (Apple-only); CMake source-swaps the GPU backend so the program modules are unchanged.
New: metal/EMMC.metal (MSL port of EMMC.cl, behaviour-preserving); metal/emtl_shim.{h,cpp} (C-ABI shim over vendored metal-cpp: unified-memory buffers, live-buffer registry to pick setBuffer vs setBytes, per-pipeline cached args re-applied per enqueue to mirror OpenCL set-once/dispatch-many); mod_CLsupport_metal.f90 (drop-in module mod_CLsupport / type OpenCL_T over the shim, same public surface incl. quiet); clfortran_metal_stub.f90 (CL_MEM_* constants so program modules' use clfortran resolves without the real lib). CMake builds *.metal -> *.metallib at build time and places them beside the .cl files.
Validation: EMMCOpenCL on Metal vs OpenCL reference (h5diff /EMData): accumSP bit-identical; accum_e/accum_z differ only by +/-1 electron per bin (max 2), the inherent chaotic-MC floating-point divergence between the Metal and OpenCL compilers. Physics equivalent.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Translates the InnerProd tiled GEMM (BLOCK_SIZE=16) from DictIndx.cl to metal/DictIndx.metal and adds DictIndx to the build-time metallib list. mod_DI was already wrapper-routed (Phase 0), so the whole DI path runs on the Metal backend with no further code changes. Validated: EMDI on Metal vs OpenCL reference (h5diff /Scan 1) -- TopDotProductList, TopMatchIndices, EulerAngles, CI, Phi/Phi1/Phi2, KAM, OSM all 0 differences (the Metal InnerProd dot products are bit-identical; no FMA divergence). Residual differences (DictionaryEulerAngles, ISM, ISMap, IndexingSuccessRate) are the pre-existing FZ-sampling non-determinism seen in the Phase 0 OpenCL-vs-OpenCL run, not the Metal backend. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
…dead Translates the remaining live OpenCL MC kernels to MSL: metal/EMMCfoil.metal (foil-geometry MC, transmitted electrons accumulated in the southern hemisphere) and metal/EMMCxyz.metal (MCxyz, interaction-volume xyz output). Both reuse EMMC.metal's validated MC structure and mod_MCOpenCL already routes them through the wrappers, so no host changes. Added to the build-time metallib list. Scoping correction: MBmoduleOpenCL.cl (ScatMat/CalcLgh/CalcLghMaster) is dead code -- no compiled module loads it; master patterns use the CPU ZGEEV CalcLgh in mod_gvectors. It is intentionally not built. With foil/Ivol done, every live OpenCL kernel (EMMC/EMMCfoil/EMMCxyz/InnerProd) is now ported to Metal. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
opencl/SourceList.cmake installs the build-time *.metallib (from Bin/opencl/) to <install>/opencl/ when Metal is enabled, via FILES_MATCHING so it tracks whatever kernels were built. Records Phase 4 status in the plan: default-Metal-on deferred until remaining verifications pass (and gated on xcrun metal availability); the GPU_T/EMGPULib rename left as an open decision (cosmetic, high-churn). Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
EMsoftOO_ENABLE_Metal_SUPPORT now defaults ON on APPLE (OFF/forced elsewhere), with a non-fatal configure warning if the Metal toolchain (xcrun -sdk macosx metal) is missing so CLT-only builds get a clear message. The GPU_T/EMGPULib rename is deferred to a separate branch (cosmetic, high-churn). Migration is functionally complete: all live OpenCL kernels ported, Metal is the default GPU backend on Apple. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
On Apple, EMsoftOO_ENABLE_Metal_SUPPORT still defaults ON, but if 'xcrun -sdk macosx -f metal' is not found at configure time (Command-Line-Tools-only install, or Xcode 16+ without the Metal Toolchain component), the build now forces Metal OFF and falls back to the OpenCL backend (re-enabling OpenCL if needed) with an explanatory warning, instead of failing at the .metallib step. A clean default build therefore works out of the box on any Mac. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Adds a section describing the native Metal backend that replaces OpenCL on macOS: what is ported (MC + DI kernels), that it is default-on on Apple with automatic OpenCL fallback, the vendored metal-cpp dependency, and the full-Xcode Metal-compiler build requirement. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Backend-neutral rename of the GPU abstraction now that both OpenCL and Metal back it: type OpenCL_T -> GPU_T and module mod_CLsupport -> mod_GPUsupport (files mod_CLsupport*.f90 -> mod_GPUsupport*.f90), across both backend implementations and all consumers (mod_MCOpenCL, mod_DI, mod_EBSDFull, mod_SEMCLwrappers, the dead mod_DIPCA, Utilities/EMOpenCLinfo, the clfortran stub, CMake source paths). A word-boundary-safe substitution preserved MCOpenCL_T (the MC program class). Per decision, the library/folder name EMOpenCLLib is kept (renaming to EMGPULib would churn every modality CMakeLists + export targets for no functional gain). Local handle variables stay named CL. This completes the OpenCL->Metal migration; all phases done and runtime-verified. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
…adowing) The Metal-only clfortran stub produces a clfortran.mod that, if a build dir is reconfigured Metal->OpenCL, shadows the real clfortran and breaks the OpenCL backend. Documents the fix (separate build dirs; non-Apple OpenCL builds unaffected) and the alternative of dropping the stub. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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Apple deprecated OpenCL; this PR adds a native Apple Metal GPU backend so the
GPU-accelerated programs keep working — and run ~2x faster — on Apple Silicon,
while OpenCL stays the backend on Windows/Linux/NVIDIA/AMD.
What changed
mod_SEMCLwrappers) through a backend-neutral GPU_T / mod_GPUsupport wrapper
surface (pure refactor; verified bit-identical to prior OpenCL output).
ExternalProjects/metal-cpp), mod_GPUsupport_metal.f90 drop-in, EMMC.metal;
selected via CMake source-swap (no program-module changes).
dead code and intentionally not ported.)
automatic fallback to OpenCL if the Metal toolchain is absent; README + design
doc (MetalMigrationPlan.md); renamed the abstraction OpenCL_T/mod_CLsupport ->
GPU_T/mod_GPUsupport (library name EMOpenCLLib kept).
Validation (h5diff vs OpenCL): MC (default/foil/Ivol), DI, EBSDFull,
SEMCLwrappers — all confirmed (linear paths bit-identical; chaotic MC differs only
by the expected ±1-electron float-divergence between GPU compilers).
Build notes