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|
;; RUN: wasm-metadce --help | filecheck %s
;; CHECK: ================================================================================
;; CHECK-NEXT: wasm-metadce INFILE
;; CHECK-NEXT:
;; CHECK-NEXT: This tool performs dead code elimination (DCE) on a larger space that the wasm
;; CHECK-NEXT: module is just a part of. For example, if you have JS and wasm that are
;; CHECK-NEXT: connected, this can DCE the combined graph. By doing so, it is able to eliminate
;; CHECK-NEXT: wasm module exports, which otherwise regular optimizations cannot.
;; CHECK-NEXT:
;; CHECK-NEXT: This tool receives a representation of the reachability graph that the wasm
;; CHECK-NEXT: module resides in, which contains abstract nodes and connections showing what
;; CHECK-NEXT: they reach. Some of those nodes can represent the wasm module's imports and
;; CHECK-NEXT: exports. The tool then completes the graph by adding the internal parts of the
;; CHECK-NEXT: module, and does DCE on the entire thing.
;; CHECK-NEXT:
;; CHECK-NEXT: This tool will output a wasm module with dead code eliminated, and metadata
;; CHECK-NEXT: describing the things in the rest of the graph that can be eliminated as well.
;; CHECK-NEXT:
;; CHECK-NEXT: The graph description file should represent the graph in the following JSON-like
;; CHECK-NEXT: notation (note, this is not true JSON, things like comments, escaping,
;; CHECK-NEXT: single-quotes, etc. are not supported):
;; CHECK-NEXT:
;; CHECK-NEXT: [
;; CHECK-NEXT: {
;; CHECK-NEXT: "name": "entity1",
;; CHECK-NEXT: "reaches": ["entity2, "entity3"],
;; CHECK-NEXT: "root": true
;; CHECK-NEXT: },
;; CHECK-NEXT: {
;; CHECK-NEXT: "name": "entity2",
;; CHECK-NEXT: "reaches": ["entity1, "entity4"]
;; CHECK-NEXT: },
;; CHECK-NEXT: {
;; CHECK-NEXT: "name": "entity3",
;; CHECK-NEXT: "reaches": ["entity1"],
;; CHECK-NEXT: "export": "export1"
;; CHECK-NEXT: },
;; CHECK-NEXT: {
;; CHECK-NEXT: "name": "entity4",
;; CHECK-NEXT: "import": ["module", "import1"]
;; CHECK-NEXT: },
;; CHECK-NEXT: ]
;; CHECK-NEXT:
;; CHECK-NEXT: Each entity has a name and an optional list of the other entities it reaches. It
;; CHECK-NEXT: can also be marked as a root, export (with the export string), or import (with
;; CHECK-NEXT: the module and import strings). DCE then computes what is reachable from the
;; CHECK-NEXT: roots.
;; CHECK-NEXT: ================================================================================
;; CHECK-NEXT:
;; CHECK-NEXT:
;; CHECK-NEXT: wasm-opt options:
;; CHECK-NEXT: -----------------
;; CHECK-NEXT:
;; CHECK-NEXT: --output,-o Output file (stdout if not specified)
;; CHECK-NEXT:
;; CHECK-NEXT: --emit-text,-S Emit text instead of binary for the
;; CHECK-NEXT: output file
;; CHECK-NEXT:
;; CHECK-NEXT: --debuginfo,-g Emit names section and debug info
;; CHECK-NEXT:
;; CHECK-NEXT: --graph-file,-f Filename of the graph description file
;; CHECK-NEXT:
;; CHECK-NEXT: --dump,-d Dump the combined graph file (useful for
;; CHECK-NEXT: debugging)
;; CHECK-NEXT:
;; CHECK-NEXT:
;; CHECK-NEXT: Tool options:
;; CHECK-NEXT: -------------
;; CHECK-NEXT:
;; CHECK-NEXT: --mvp-features,-mvp Disable all non-MVP features
;; CHECK-NEXT:
;; CHECK-NEXT: --all-features,-all Enable all features
;; CHECK-NEXT:
;; CHECK-NEXT: --detect-features (deprecated - this flag does nothing)
;; CHECK-NEXT:
;; CHECK-NEXT: --quiet,-q Emit less verbose output and hide trivial
;; CHECK-NEXT: warnings.
;; CHECK-NEXT:
;; CHECK-NEXT: --experimental-poppy Parse wast files as Poppy IR for testing
;; CHECK-NEXT: purposes.
;; CHECK-NEXT:
;; CHECK-NEXT: --enable-sign-ext Enable sign extension operations
;; CHECK-NEXT:
;; CHECK-NEXT: --disable-sign-ext Disable sign extension operations
;; CHECK-NEXT:
;; CHECK-NEXT: --enable-threads Enable atomic operations
;; CHECK-NEXT:
;; CHECK-NEXT: --disable-threads Disable atomic operations
;; CHECK-NEXT:
;; CHECK-NEXT: --enable-mutable-globals Enable mutable globals
;; CHECK-NEXT:
;; CHECK-NEXT: --disable-mutable-globals Disable mutable globals
;; CHECK-NEXT:
;; CHECK-NEXT: --enable-nontrapping-float-to-int Enable nontrapping float-to-int
;; CHECK-NEXT: operations
;; CHECK-NEXT:
;; CHECK-NEXT: --disable-nontrapping-float-to-int Disable nontrapping float-to-int
;; CHECK-NEXT: operations
;; CHECK-NEXT:
;; CHECK-NEXT: --enable-simd Enable SIMD operations and types
;; CHECK-NEXT:
;; CHECK-NEXT: --disable-simd Disable SIMD operations and types
;; CHECK-NEXT:
;; CHECK-NEXT: --enable-bulk-memory Enable bulk memory operations
;; CHECK-NEXT:
;; CHECK-NEXT: --disable-bulk-memory Disable bulk memory operations
;; CHECK-NEXT:
;; CHECK-NEXT: --enable-exception-handling Enable exception handling operations
;; CHECK-NEXT:
;; CHECK-NEXT: --disable-exception-handling Disable exception handling operations
;; CHECK-NEXT:
;; CHECK-NEXT: --enable-tail-call Enable tail call operations
;; CHECK-NEXT:
;; CHECK-NEXT: --disable-tail-call Disable tail call operations
;; CHECK-NEXT:
;; CHECK-NEXT: --enable-reference-types Enable reference types
;; CHECK-NEXT:
;; CHECK-NEXT: --disable-reference-types Disable reference types
;; CHECK-NEXT:
;; CHECK-NEXT: --enable-multivalue Enable multivalue functions
;; CHECK-NEXT:
;; CHECK-NEXT: --disable-multivalue Disable multivalue functions
;; CHECK-NEXT:
;; CHECK-NEXT: --enable-gc Enable garbage collection
;; CHECK-NEXT:
;; CHECK-NEXT: --disable-gc Disable garbage collection
;; CHECK-NEXT:
;; CHECK-NEXT: --enable-memory64 Enable memory64
;; CHECK-NEXT:
;; CHECK-NEXT: --disable-memory64 Disable memory64
;; CHECK-NEXT:
;; CHECK-NEXT: --enable-typed-function-references Enable typed function references
;; CHECK-NEXT:
;; CHECK-NEXT: --disable-typed-function-references Disable typed function references
;; CHECK-NEXT:
;; CHECK-NEXT: --enable-gc-nn-locals Enable GC non-null locals
;; CHECK-NEXT:
;; CHECK-NEXT: --disable-gc-nn-locals Disable GC non-null locals
;; CHECK-NEXT:
;; CHECK-NEXT: --enable-relaxed-simd Enable relaxed SIMD
;; CHECK-NEXT:
;; CHECK-NEXT: --disable-relaxed-simd Disable relaxed SIMD
;; CHECK-NEXT:
;; CHECK-NEXT: --enable-extended-const Enable extended const expressions
;; CHECK-NEXT:
;; CHECK-NEXT: --disable-extended-const Disable extended const expressions
;; CHECK-NEXT:
;; CHECK-NEXT: --no-validation,-n Disables validation, assumes inputs are
;; CHECK-NEXT: correct
;; CHECK-NEXT:
;; CHECK-NEXT: --pass-arg,-pa An argument passed along to optimization
;; CHECK-NEXT: passes being run. Must be in the form
;; CHECK-NEXT: KEY@VALUE
;; CHECK-NEXT:
;; CHECK-NEXT: --nominal Force all GC type definitions to be
;; CHECK-NEXT: parsed as nominal.
;; CHECK-NEXT:
;; CHECK-NEXT: --structural Force all GC type definitions to be
;; CHECK-NEXT: parsed as structural (i.e.
;; CHECK-NEXT: equirecursive). This is the default.
;; CHECK-NEXT:
;; CHECK-NEXT: --hybrid Force all GC type definitions to be
;; CHECK-NEXT: parsed using the isorecursive hybrid type
;; CHECK-NEXT: system.
;; CHECK-NEXT:
;; CHECK-NEXT:
;; CHECK-NEXT: General options:
;; CHECK-NEXT: ----------------
;; CHECK-NEXT:
;; CHECK-NEXT: --version Output version information and exit
;; CHECK-NEXT:
;; CHECK-NEXT: --help,-h Show this help message and exit
;; CHECK-NEXT:
;; CHECK-NEXT: --debug,-d Print debug information to stderr
;; CHECK-NEXT:
|
