tree 5b00ab9a09df82616a7079988adb2a3e2ea98ca1
parent 9280ae1171ce15912abd3b6b0ef569428d1206f6
author Thomas Lively <tlively@google.com> 1567626639 +0000
committer Thomas Lively <tlively@google.com> 1567626639 +0000

[WebAssembly] Initialize memory in start function

Summary:
 - `__wasm_init_memory` is now the WebAssembly start function instead
   of being called from `__wasm_call_ctors` or called directly by the
   runtime.
 - Adds a new synthetic data symbol `__wasm_init_memory_flag` that is
   atomically incremented from zero to one by the thread responsible
   for initializing memory.
 - All threads now unconditionally perform data.drop on all passive
   segments.
 - Removes --passive-segments and --active-segments flags and controls
   segment type based on --shared-memory instead. The deleted flags
   were only present to ameliorate the upgrade path in Emscripten.

Reviewers: sbc100, aheejin

Subscribers: dschuff, jgravelle-google, sunfish, jfb, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D65783

git-svn-id: https://llvm.org/svn/llvm-project/lld/trunk@370965 91177308-0d34-0410-b5e6-96231b3b80d8