version_40: metadce fixes (#1329)

* ignore missing imports (the wasm may have already had them optimized out)

 * handle segments that hold on to globals (root them, for now, as we can't remove segments)

 * run reorder-functions, as the optimal order may have changed after we dce

* fix global, global init, and segment offset reachability

* fix import rooting and processing - imports may be imported more than once

1.37.24

Fixed compilation in GCC 7 (#1301)

1.37.23: Provide AddImport/AddExport for each element in the C-API (#1292)

* Provide AddImport/AddExport for each element in the C-API

version_39

Build binaryen.js and wasm.js on Travis CI (#1260)

1.37.22

fix ssaify bug where we failed to update the location of values as we…

version_38: Add --trap-mode=allow/clamp/js argument to asm2wasm and s2wasm (#1210)

* Add --trap-mode=allow/clamp/js argument to asm2wasm and s2wasm

* Update asm2wasm and auto_update_tests scripts to use --trap-mode

* Throw std::invalid_argument instead of adding a new Invalid TrapMode type

* Remove legacy asm2wasm trap mode arguments

1.37.20: Inline many (#1125)

* Improve inlining pass to inline single-use functions that are fairly small, which makes it useful for removing unnecessary global constructors from clang.

 * Add an inlining-optimizing pass that also optimizes where it inlined, as new opportunities arise. enable that it by default in O2+

* In addition, in -O3+ also inline small functions with multiple uses. This helps a lot with things like safe-int-divide functions (where each int divide is replaced by a safe divide that won't trap). Inlining gets rid of around half of the overhead there.