[lld] r343156 - Revert "[WebAssembly] Update docs"

[Sam Clegg via llvm-commits]

Author: sbc
Date: Wed Sep 26 17:42:49 2018
New Revision: 343156

URL: http://llvm.org/viewvc/llvm-project?rev=343156&view=rev
Log:
Revert "[WebAssembly] Update docs"

This change reverts rL343155.  It broke the builtbot, even though
it works for me locally:
http://lab.llvm.org:8011/builders/lld-sphinx-docs/builds/26336

Must be a sphinx version issue I guess.

Modified:
    lld/trunk/docs/README.txt
    lld/trunk/docs/WebAssembly.rst

Modified: lld/trunk/docs/README.txt
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/docs/README.txt?rev=343156&r1=343155&r2=343156&view=diff
==============================================================================
--- lld/trunk/docs/README.txt (original)
+++ lld/trunk/docs/README.txt Wed Sep 26 17:42:49 2018
@@ -6,4 +6,7 @@ currently tested with Sphinx 1.1.3.
 
 We currently use the 'nature' theme and a Beaker inspired structure.
 
-See sphinx_intro.rst for more details.
+To rebuild documents into html:
+
+   [/lld/docs]> make html
+

Modified: lld/trunk/docs/WebAssembly.rst
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/docs/WebAssembly.rst?rev=343156&r1=343155&r2=343156&view=diff
==============================================================================
--- lld/trunk/docs/WebAssembly.rst (original)
+++ lld/trunk/docs/WebAssembly.rst Wed Sep 26 17:42:49 2018
@@ -1,10 +1,13 @@
 WebAssembly lld port
 ====================
 
+Note: The WebAssembly port is still a work in progress and is be lacking
+certain features.
+
 The WebAssembly version of lld takes WebAssembly binaries as inputs and produces
-a WebAssembly binary as its output.  For the most part it tries to mimic the
-behaviour of traditional ELF linkers and specifically the ELF lld port.  Where
-possible that command line flags and the semantics should be the same.
+a WebAssembly binary as its output.  For the most part this port tried to mimic
+the behaviour of traditional ELF linkers and specifically the ELF lld port.
+Where possible that command line flags and the semantics should be the same.
 
 
 Object file format
@@ -20,86 +23,14 @@ currently requires enabling the experime
 ``-DLLVM_EXPERIMENTAL_TARGETS_TO_BUILD=WebAssembly``.
 
 
-Usage
------
-
-The WebAssembly version of lld is installed as **wasm-ld**.  It shared many 
-common linker flags with **ld.lld** but also includes several
-WebAssembly-specific options:
-
-.. option:: --no-entry
-
-  Don't search for the entry point symbol (by default ``_start``).
-
-.. option:: --export-table
-
-  Export the function table to the environment.
-
-.. option:: --import-table
-
-  Import the function table from the environment.
-
-.. option:: --export-all
-
-  Export all symbols (normally combined with --no-gc-sections)
-
-.. option:: --[no-]export-default
-
-  Export symbols marked as 'default' visibility.  Default: true
-
-.. option:: --global-base=<value>
-
-  Address at which to place global data
-
-.. option:: --[no-]merge-data-segments
-
-  Enable/Disble merging of data segments.  Default: true
-
-.. option:: --stack-first
-
-  Place stack at start of linear memory rather than after data
-
-.. option:: --compress-relocations
-
-  Compress the relocation targets in the code section.
-
-.. option:: --allow-undefined
-
-  Allow undefined symbols in linked binary
-
-.. option:: --import-memory
-
-  Import memory from the environment
-
-.. option:: --initial-memory=<value>
-
-  Initial size of the linear memory. Default: static data size
-
-.. option:: --max-memory=<value>
-
-  Maximum size of the linear memory. Default: unlimited
-
-By default the function table is neither imported nor exported.
-
-Symbols are exported if they are marked as ``visibility=default`` at compile
-time or if they are included on the command line via ``--export``.
-
-Since WebAssembly is designed with size in mind the linker defaults to
-``--gc-sections`` which means that all un-used functions and data segments will
-be stripped from the binary.
-
-The symbols which are preserved by default are:
-
-- The entry point (by default ``_start``).
-- Any symbol which is to be exported.
-- Any symbol transitively referenced by the above.
-
-
 Missing features
 ----------------
 
-- Merging of data section similiar to ``SHF_MERGE`` in the ELF world is not
-  supported.
-- No support for creating shared libaries.  The spec for shared libraries in
-  WebAssembly is still in flux:
-  https://github.com/WebAssembly/tool-conventions/blob/master/DynamicLinking.md
+There are several key features that are not yet implement in the WebAssembly
+ports:
+
+- COMDAT support.  This means that support for C++ is still very limited.
+- Function stripping.  Currently there is no support for ``--gc-sections`` so
+  functions and data from a given object will linked as a unit.
+- Section start/end symbols.  The synthetic symbols that mark the start and
+  of data regions are not yet created in the output file.