зеркало из https://github.com/mozilla/gecko-dev.git
23854fd5a5
This patch cleans up wasm compiler selection and a few related things with as few semantic changes as possible. The intent is to centralize compiler availability computation so that all parts of the system stay in sync and it is easy to change compiler selection policy. First, we introduce new predicates <Compiler>Available(cx) to test for the actual availability of a compiler. These predicates take into account whether a compiler is compiled into the executable, whether it supports the hardware, whether it is (currently) selected by options/switches, and whether it can be used as a result of the runtime environment (for example, Ion and Cranelift are not available if the debugger is observing the page or if the GC feature is enabled; Cranelift is not available if shared memory and atomics are enabled). We switch to using these predicates almost everywhere that used <Compiler>CanCompile() or cx->options().wasm<Compiler>(), since those don't tell the full story. Second, we implement a priority order of the optimizing compilers and make it easy to change this order (see comments in code). At the moment, Cranelift is prioritized over Ion since Ion is enabled by default and Cranelift is not; thus the desire of somebody flipping the pref for Cranelift is to deselect Ion. The priority order may change in the future or may become platform-dependent. The default compiler selection in both browser and shell remains Baseline+Ion. Third, we rename HasCompilerSupport() as HasPlatformSupport(), since the predicate does not test whether compilers are available, only whether they are present in the executable and support the hardware. And to make that more sensible, <Compiler>CanCompile() is renamed as <Compiler>PlatformSupport(). Fourth, we remove some redundant testing predicates (we don't need both wasmDebugSupport and wasmDebuggingIsSupported, nor do we need wasmUsesCranelift because wasmCompileMode is more reliable). Fifth, we introduce a few new test cases that try to ensure that compiler selection works as it should. These are white-box and may need to change if the compiler priority order changes. Sixth, we rename the internal wasm::Has<Feature>Support() predicates as wasm::<Feature>Available(), since they all actually test for compiler availability. Differential Revision: https://phabricator.services.mozilla.com/D64946 --HG-- extra : moz-landing-system : lando |
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| ductwork/debugger | ||
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| ipc | ||
| public | ||
| rust | ||
| src | ||
| xpconnect | ||
| app.mozbuild | ||
| ffi.configure | ||
| moz.build | ||
| moz.configure | ||
| sub.configure | ||