Upgrade Emscripten targets to use upstream LLVM backend

 - Compatible with Emscripten 1.38.46-upstream or later upstream.
 - Refactors the Emscripten target spec to share code with other wasm
   targets.
 - Replaces the old incorrect wasm32 C call ABI with the correct one,
   preserving the old one as wasm32_bindgen_compat for wasm-bindgen
   compatibility.
 - Updates the varargs ABI used by Emscripten and deletes the old one.
 - Removes the obsolete wasm32-experimental-emscripten target.
 - Uses EMCC_CFLAGS on CI to avoid the timeout problems with #63649.

6 files changed, 31 insertions, 116 deletions

diff --git a/src/ci/docker/asmjs/Dockerfile b/src/ci/docker/asmjs/Dockerfile
index 3abaab6b34e..75db374907d 100644
--- a/src/ci/docker/asmjs/Dockerfile
+++ b/src/ci/docker/asmjs/Dockerfile
@@ -11,7 +11,8 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
   cmake \
   sudo \
   gdb \
-  xz-utils
+  xz-utils \
+  bzip2
 
 COPY scripts/emscripten.sh /scripts/
 RUN bash /scripts/emscripten.sh
@@ -20,28 +21,21 @@ COPY scripts/sccache.sh /scripts/
 RUN sh /scripts/sccache.sh
 
 ENV PATH=$PATH:/emsdk-portable
-ENV PATH=$PATH:/emsdk-portable/clang/e1.38.15_64bit/
-ENV PATH=$PATH:/emsdk-portable/emscripten/1.38.15/
-ENV PATH=$PATH:/emsdk-portable/node/8.9.1_64bit/bin/
-ENV EMSCRIPTEN=/emsdk-portable/emscripten/1.38.15/
-ENV BINARYEN_ROOT=/emsdk-portable/clang/e1.38.15_64bit/binaryen/
+ENV PATH=$PATH:/emsdk-portable/upstream/emscripten/
+ENV PATH=$PATH:/emsdk-portable/node/12.9.1_64bit/bin/
+ENV BINARYEN_ROOT=/emsdk-portable/upstream/
 ENV EM_CONFIG=/emsdk-portable/.emscripten
 
 ENV TARGETS=asmjs-unknown-emscripten
 
-ENV RUST_CONFIGURE_ARGS --enable-emscripten --disable-optimize-tests
+# Use -O1 optimizations in the link step to reduce time spent optimizing JS.
+# FIXME: Switch to testing wasm32-unknown-emscripten and -O1 to save more time
+# once the CI picks up https://github.com/rust-lang/cargo/pull/7476.
+ENV EMCC_CFLAGS=-O1
 
-ENV SCRIPT python2.7 ../x.py test --target $TARGETS \
-  src/test/ui \
-  src/test/run-fail \
-  src/libstd \
-  src/liballoc \
-  src/libcore
+ENV SCRIPT python2.7 ../x.py test --target $TARGETS
 
-# Debug assertions in rustc are largely covered by other builders, and LLVM
-# assertions cause this builder to slow down by quite a large amount and don't
-# buy us a huge amount over other builders (not sure if we've ever seen an
-# asmjs-specific backend assertion trip), so disable assertions for these
-# tests.
-ENV NO_LLVM_ASSERTIONS=1
+# This is almost identical to the wasm32-unknown-emscripten target, so
+# running with assertions again is not useful
 ENV NO_DEBUG_ASSERTIONS=1
+ENV NO_LLVM_ASSERTIONS=1
diff --git a/src/ci/docker/disabled/wasm32-exp/Dockerfile b/src/ci/docker/disabled/wasm32-exp/Dockerfile
deleted file mode 100644
index 420d47b314c..00000000000
--- a/src/ci/docker/disabled/wasm32-exp/Dockerfile
+++ /dev/null
@@ -1,35 +0,0 @@
-FROM ubuntu:16.04
-
-RUN apt-get update && apt-get install -y --no-install-recommends \
-  g++ \
-  make \
-  file \
-  curl \
-  ca-certificates \
-  python \
-  git \
-  cmake \
-  sudo \
-  gdb \
-  xz-utils \
-  jq \
-  bzip2
-
-# emscripten
-COPY scripts/emscripten-wasm.sh /scripts/
-COPY wasm32-exp/node.sh /usr/local/bin/node
-RUN bash /scripts/emscripten-wasm.sh
-
-# cache
-COPY scripts/sccache.sh /scripts/
-RUN sh /scripts/sccache.sh
-
-# env
-ENV PATH=/wasm-install/emscripten:/wasm-install/bin:$PATH
-ENV EM_CONFIG=/root/.emscripten
-
-ENV TARGETS=wasm32-experimental-emscripten
-
-ENV RUST_CONFIGURE_ARGS --experimental-targets=WebAssembly
-
-ENV SCRIPT python2.7 ../x.py test --target $TARGETS
diff --git a/src/ci/docker/disabled/wasm32-exp/node.sh b/src/ci/docker/disabled/wasm32-exp/node.sh
deleted file mode 100755
index aa938971c70..00000000000
--- a/src/ci/docker/disabled/wasm32-exp/node.sh
+++ /dev/null
@@ -1,9 +0,0 @@
-#!/usr/bin/env bash
-
-path="$(dirname $1)"
-file="$(basename $1)"
-
-shift
-
-cd "$path"
-exec /node-v8.0.0-linux-x64/bin/node "$file" "$@"
diff --git a/src/ci/docker/disabled/wasm32/Dockerfile b/src/ci/docker/disabled/wasm32/Dockerfile
index 0d2bd39303e..aeccbb9bdc0 100644
--- a/src/ci/docker/disabled/wasm32/Dockerfile
+++ b/src/ci/docker/disabled/wasm32/Dockerfile
@@ -11,9 +11,9 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
   cmake \
   sudo \
   gdb \
-  xz-utils
+  xz-utils \
+  bzip2
 
-# emscripten
 COPY scripts/emscripten.sh /scripts/
 RUN bash /scripts/emscripten.sh
 
@@ -21,12 +21,19 @@ COPY scripts/sccache.sh /scripts/
 RUN sh /scripts/sccache.sh
 
 ENV PATH=$PATH:/emsdk-portable
-ENV PATH=$PATH:/emsdk-portable/clang/e1.38.15_64bit/
-ENV PATH=$PATH:/emsdk-portable/emscripten/1.38.15/
-ENV PATH=$PATH:/emsdk-portable/node/8.9.1_64bit/bin/
-ENV EMSCRIPTEN=/emsdk-portable/emscripten/1.38.15/
-ENV BINARYEN_ROOT=/emsdk-portable/clang/e1.38.15_64bit/binaryen/
+ENV PATH=$PATH:/emsdk-portable/upstream/emscripten/
+ENV PATH=$PATH:/emsdk-portable/node/12.9.1_64bit/bin/
+ENV BINARYEN_ROOT=/emsdk-portable/upstream/
 ENV EM_CONFIG=/emsdk-portable/.emscripten
 
 ENV TARGETS=wasm32-unknown-emscripten
-ENV SCRIPT python2.7 ../x.py test --target $TARGETS
+
+# FIXME: Re-enable these tests once https://github.com/rust-lang/cargo/pull/7476
+# is picked up by CI
+ENV SCRIPT python2.7 ../x.py test --target $TARGETS \
+    --exclude src/libcore \
+    --exclude src/liballoc \
+    --exclude src/libproc_macro \
+    --exclude src/libstd \
+    --exclude src/libterm \
+    --exclude src/libtest
diff --git a/src/ci/docker/scripts/emscripten-wasm.sh b/src/ci/docker/scripts/emscripten-wasm.sh
deleted file mode 100644
index e4a93d7a100..00000000000
--- a/src/ci/docker/scripts/emscripten-wasm.sh
+++ /dev/null
@@ -1,37 +0,0 @@
-set -ex
-
-hide_output() {
-  set +x
-  on_err="
-echo ERROR: An error was encountered with the build.
-cat /tmp/build.log
-exit 1
-"
-  trap "$on_err" ERR
-  bash -c "while true; do sleep 30; echo \$(date) - building ...; done" &
-  PING_LOOP_PID=$!
-  $@ &> /tmp/build.log
-  trap - ERR
-  kill $PING_LOOP_PID
-  rm -f /tmp/build.log
-  set -x
-}
-
-# Download last known good emscripten from WebAssembly waterfall
-BUILD=$(curl -fL https://storage.googleapis.com/wasm-llvm/builds/linux/lkgr.json | \
-    jq '.build | tonumber')
-curl -sL https://storage.googleapis.com/wasm-llvm/builds/linux/$BUILD/wasm-binaries.tbz2 | \
-    hide_output tar xvkj
-
-# node 8 is required to run wasm
-cd /
-curl -sL https://nodejs.org/dist/v8.0.0/node-v8.0.0-linux-x64.tar.xz | \
-    tar -xJ
-
-# Make emscripten use wasm-ready node and LLVM tools
-echo "EMSCRIPTEN_ROOT = '/wasm-install/emscripten'" >> /root/.emscripten
-echo "NODE_JS='/usr/local/bin/node'" >> /root/.emscripten
-echo "LLVM_ROOT='/wasm-install/bin'" >> /root/.emscripten
-echo "BINARYEN_ROOT = '/wasm-install'" >> /root/.emscripten
-echo "COMPILER_ENGINE = NODE_JS" >> /root/.emscripten
-echo "JS_ENGINES = [NODE_JS]" >> /root/.emscripten
diff --git a/src/ci/docker/scripts/emscripten.sh b/src/ci/docker/scripts/emscripten.sh
index 47196e89396..9c7a09e227a 100644
--- a/src/ci/docker/scripts/emscripten.sh
+++ b/src/ci/docker/scripts/emscripten.sh
@@ -17,20 +17,15 @@ exit 1
   set -x
 }
 
-cd /
-curl -fL https://mozilla-games.s3.amazonaws.com/emscripten/releases/emsdk-portable.tar.gz | \
-    tar -xz
-
+git clone https://github.com/emscripten-core/emsdk.git /emsdk-portable
 cd /emsdk-portable
-./emsdk update
-hide_output ./emsdk install sdk-1.38.15-64bit
-./emsdk activate sdk-1.38.15-64bit
+hide_output ./emsdk install 1.38.46-upstream
+./emsdk activate 1.38.46-upstream
 
 # Compile and cache libc
 source ./emsdk_env.sh
 echo "main(){}" > a.c
 HOME=/emsdk-portable/ emcc a.c
-HOME=/emsdk-portable/ emcc -s BINARYEN=1 a.c
 rm -f a.*
 
 # Make emsdk usable by any user