Add Ttir D2m Lowering

TTIR elementwise → D2M (TTMetal path)

Allowed edits (these layers):

1. Tablegen — e.g. include/ttmlir/Dialect/D2M/IR/D2MGenericRegionOps.td (and any other .td you already own for the op). Pick the same base class as the nearest op (unary: D2M_GenericRegionComputeUnaryDstOp; typical binary: …FPUOrSFPUBinary; ternary: …TernaryDstOp). Prefer ops that need no hand-written C++ in D2MGenericRegionOps.cpp; that file is out of scope for this workflow.

2. lib/Conversion/TTIRToD2M/TTIRToD2M.cpp — in populateTTIRToD2MPatterns, add one line to the big patterns.add< … > list with the other elementwise rewriters, e.g. D2MNamedElementwiseRewriter<ttir::YourOp, d2m::TileYourOp>, (keep ordering consistent with neighbors). Use notifyMatchFailure inside patterns, not emitOpError.

3. lib/Conversion/D2MToTTKernel/D2MToTTKernel.cpp — extend ComputeOpMap / IntComputeOpMap and the patterns.add<…D2MSFPUOpsRewriter…> list to match the nearest unary/binary tile op.

   If the TTKernel op takes i32-encoded scalar params (float attrs bit-reinterpreted, or int attrs, or a runtime scalar Value), reuse the shared helpers defined at the top of the anonymous namespace rather than re-inlining a lambda:

   • floatAttrToI32Bits(rewriter, loc, attr) — FloatAttr → i32 bits (e.g. selu scale/alpha, clamp_scalar float min/max).
   • intAttrToI32(rewriter, loc, attr) — IntegerAttr → sign-extended i32 (e.g. clamp_scalar int min/max).
   • scalarToI32Bits(rewriter, loc, value) — runtime scalar Value → i32 (float widened+bitcast, int sign-extended/truncated). Used by binop_with_scalar-style scalar rhs lowerings.

   Ops with scalar attributes typically need a dedicated else if constexpr (std::is_same_v<SFPUOp, ttkernel::FooTileOp>) branch in the D2MSFPUOpsRewriter body that pulls attrs off op and calls the shared helper — see the SeluTileOp / ClampScalarTileOp branches as templates.

4. include/ttmlir/Target/TTKernel/TTKernelIncludesMap.h (only if the kernel API callee is new) — the ScopedModuleHelper in lib/Target/TTKernel/TTKernelToCpp.cpp no longer hardcodes api/compute/eltwise_unary/*.h. It walks the region and looks up each emitc.call_opaque callee in getCalleeToHeadersMap(). If your op lowers to a tt-metal SFPU helper (foo_tile / foo_tile_init) that isn't already in that map, add entries like:

   {"foo_tile",      {"api/compute/eltwise_unary/foo.h", ""}},
   {"foo_tile_init", {"api/compute/eltwise_unary/foo.h", ""}},

   The callee string must match the TTKernel_SFPUOp<"foo_tile", …> / TTKernel_InitOp<"foo_tile_init"> name in TTKernelOps.td exactly. Do not edit TTKernelToCpp.cpp to add includes directly — the old unconditional emitc::IncludeOp block was removed. Without a map entry, wormhole JIT can fail with "foo_tile was not declared in this scope" in chlkc_unpack.cpp.

Out of scope here: D2MGenericRegionOps.cpp, TTKernelToCpp.cpp. For TTNN / flatbuffer / full builder parity across all targets, use .claude/skills/add-op/SKILL.md.

Tests (minimal): extend existing TTIR→D2M lit at test/ttmlir/Conversion/TTIRToD2M/named_to_generic.mlir. Chain the new op into the SSA dataflow of the existing named_elementwise function (bump the %N numbering and add a // CHECK: d2m.tile_<op> + the ttir.<op> call) — do not create a separate named_elementwise_* func for the new op. No lit under test/ttmlir/Conversion/D2MToTTKernel/ is required.

Golden (TTMetal-only, no TTNN): add ttir_<op>.mlir under mlir_snippets/ttir/ — one snippet per new op so test_parse_split_ops.py exercises parse/split for each. Add the golden in tools/golden/mapping.py and the matching @tag / @parse / @split in tools/builder/ttir/ttir_builder.py (same pattern as square / exp: pass output_type_mlir into the golden, no _op_proxy).