A home is the 8-byte frame word that holds a temporarytemporary nanofilA temporary is a function-local IR name, tmp(N), holding one word of one class. Parameters, phis and instructions define temporaries; operands read them. Names are ground terms, compared only for equality: no logic variable appears in IR., a phiphi nanofilA phi phi(tmp(D), K, [Pred-Value]) gives D the value paired with the block control came from. A block's phis run together on entry, each reading its operand as it stood at the end of the predecessor.'s shadowshadow nanofilA shadow is a slot that holds a copy on the side, in two unrelated places. In the backends, a phi's shadow slot holds the incoming value during a parallel copy (it may be a home). In launder.pl, a local integer's capability shadow is a pointer slot that holds the capability of the value last stored in the integer (launder:launder_func/4, launder). or a pointer's address word in the stack-homed stream amd64_regs starts from (guide.md, 12. Register homes). Scalar homes are w or l only; float temporaries are kept out of them.

Under --registers=temps|pointers a home may be mapped to a register (amd64_regs:regs_asm/6amd64_regs.plregs_asm+Mode, +Metadata, +Before, -After, -Checked, -ReportdetMode is map (3a's map alone, unchecked, for a layout choice; Final is then not to be emitted) or frame(Cells) (step 3a, then step 3b's operand rewrite with the frame cells of docs/perf.md 5a-loads). Metadata is regs_metadata(Setjmp, Impl, Homes, Saves) with a save slot for every callee-saved register. Checked is the metadata and map the checker validated: ch…); the register checker refuses a home that overlaps a rootroot Fil-CA root is a frame word the collector scans for live capabilities: an entry of the Pizderson frame's lowers[] (the record each function keeps on the stack: a parent link, an origin and the lowers), a local's stack aux, or a jmpbuf root (filc_abi:lower_function/5, amd64_regs_check:valid_map/3). Every live lower is in one at every safepoint, so registers never hold the only copy.. Homes are a backend matter, with no counterpart in the formal model.