* cranelift-wasm: translate Wasm loads into lower-level CLIF operations
Rather than using `heap_{load,store,addr}`.
* cranelift: Remove the `heap_{addr,load,store}` instructions
These are now legalized in the `cranelift-wasm` frontend.
* cranelift: Remove the `ir::Heap` entity from CLIF
* Port basic memory operation tests to .wat filetests
* Remove test for verifying CLIF heaps
* Remove `heap_addr` from replace_branching_instructions_and_cfg_predecessors.clif test
* Remove `heap_addr` from readonly.clif test
* Remove `heap_addr` from `table_addr.clif` test
* Remove `heap_addr` from the simd-fvpromote_low.clif test
* Remove `heap_addr` from simd-fvdemote.clif test
* Remove `heap_addr` from the load-op-store.clif test
* Remove the CLIF heap runtest
* Remove `heap_addr` from the global_value.clif test
* Remove `heap_addr` from fpromote.clif runtests
* Remove `heap_addr` from fdemote.clif runtests
* Remove `heap_addr` from memory.clif parser test
* Remove `heap_addr` from reject_load_readonly.clif test
* Remove `heap_addr` from reject_load_notrap.clif test
* Remove `heap_addr` from load_readonly_notrap.clif test
* Remove `static-heap-without-guard-pages.clif` test
Will be subsumed when we port `make-heap-load-store-tests.sh` to generating
`.wat` tests.
* Remove `static-heap-with-guard-pages.clif` test
Will be subsumed when we port `make-heap-load-store-tests.sh` over to `.wat`
tests.
* Remove more heap tests
These will be subsumed by porting `make-heap-load-store-tests.sh` over to `.wat`
tests.
* Remove `heap_addr` from `simple-alias.clif` test
* Remove `heap_addr` from partial-redundancy.clif test
* Remove `heap_addr` from multiple-blocks.clif test
* Remove `heap_addr` from fence.clif test
* Remove `heap_addr` from extends.clif test
* Remove runtests that rely on heaps
Heaps are not a thing in CLIF or the interpreter anymore
* Add generated load/store `.wat` tests
* Enable memory-related wasm features in `.wat` tests
* Remove CLIF heap from fcmp-mem-bug.clif test
* Add a mode for compiling `.wat` all the way to assembly in filetests
* Also generate WAT to assembly tests in `make-load-store-tests.sh`
* cargo fmt
* Reinstate `f{de,pro}mote.clif` tests without the heap bits
* Remove undefined doc link
* Remove outdated SVG and dot file from docs
* Add docs about `None` returns for base address computation helpers
* Factor out `env.heap_access_spectre_mitigation()` to a local
* Expand docs for `FuncEnvironment::heaps` trait method
* Restore f{de,pro}mote+load clif runtests with stack memory
* cranelift: Add heap support to filetest infrastructure
* cranelift: Explicit heap pointer placement in filetest annotations
* cranelift: Add documentation about the Heap directive
* cranelift: Clarify that heap filetests pointers must be laid out sequentially
* cranelift: Use wrapping add when computing bound pointer
* cranelift: Better error messages when invalid signatures are found for heap file tests.
